RU2639130C1 - Method for estimation of professional risk to health related to arterial hypertension development for workers engaged in underground mining under conditions of labour with production noise at levels above permissible - Google Patents

Abstract

FIELD: medicine.

SUBSTANCE: invention discloses a method for estimation of the professional risk to health related to arterial hypertension development for workers engaged in underground mining under conditions of labour with production noise at levels above permissible. The following laboratory indicators are determined in the blood of workers carrying out underground mining under the conditions of labour with productive noise above the permissible level: contents of high density lipoprotein, homocysteine, atherogenic index, malonic dialdehyde level, antioxidant activity level, vascular endothelium state through the degree of reduction of brachial artery diameter growth; in the case of confirmation for all laboratory parameters of the occupational conditioning, the probability p_i ¹ of deviation of the vascular endothelium state and the probability p_i ² of arterial hypertension development in workers with deviations from the normal state of the vascular endothelium are determined. The professional risk R_i ^AG to workers health is calculated.

EFFECT: increased method accuracy and reliability.

2 tbl,1 ex

Description

The invention relates to occupational health and medicine, in particular to methods for identifying the adverse effects of industrial noise on the risk of workers developing professionally caused arterial hypertension (hereinafter - AH). The method allows to predict the risk of development in workers of professionally determined arterial hypertension based on the establishment of clinical and laboratory parameters characterizing the pathogenetic links in the development of arterial hypertension.

In recent years, there has been an increase in the primary disability rate among the able-bodied population, loss of work due to medical contraindications. The relevance of the invention is determined by the significant prevalence of cardiovascular pathology (26.6%) among people of working age employed in hazardous industries and persisting high cardiovascular mortality (7.3%). The professional factor - noise, has a negative effect on professionally determined arterial hypertension of employees. Acceptable noise levels at work are 80 dBA, while underground workers are exposed to noise levels of 85-94 dBA, which is a professional health risk.

Under professional risk is understood the probability of damage (loss) to the health or death of the employee associated with the fulfillment of his duties under an employment contract or contract (Book "Occupational Health": Textbook. / Ed. By N.F. Izmerov, V.F. Kirillov. - M .: GEOTAR - Media, 2010.592 p. Http://vmede.org/sait/?page=4&id=Gigiena_truda_izmerov_2010&menu=Gigiena_truda_izmerov_2010).

Currently, occupational risk assessment includes the following steps:

- assessment of the structure and degree of occupational risk (quantitative characteristics of exposure (in our case, noise) - factor level, duration of work, length of service, qualitative characteristics of exposure - tropism of the factor, target organs);

- assessment of the class of working conditions, urgency and scope of preventive measures.

The occupational risk assessment methodology developed by domestic occupational hygienists, taking into account the recommendations of the WHO and ILO, includes the following criteria:

- a preliminary assessment of the indicators of Guidelines R 2.2.2006-05 “Occupational health. Guidelines for the hygienic assessment of working environment and labor factors. Criteria and classification of working conditions ”;

- the final biomedical assessment of health and life indicators, a scale of classes of working conditions by categories of a priori professional risk (it is the basis of Guidelines R 2.2.2006-05) and

- a scale of the degree of connection of health disorders with work by the values of relative risk and the etiological share of the factor (R 2.2.1766-03 “Guidelines for assessing occupational risk to the health of workers. Organizational and methodological foundations, principles and evaluation criteria”).

Guidelines R 2.2.2006-05 include a description of hygienic working conditions corresponding to the classes (subclasses): optimal, permissible, harmful (with four subclasses according to the degree of harmfulness) and dangerous. The forecast of the consequences for the employee’s health in case of non-compliance with hygienic criteria of production factors is a priori carried out taking into account the excess of standard levels. At the same time, the connection between the employee’s health impairment and the effects of the environment is not taken into account.

Methodology Р 2.2.1766-03 allows the establishment of a causal relationship of health problems of an employee from the effects of the working environment, which is expressed in determining the degree of professional conditionality of health disorders of workers of certain professional groups, but does not allow prediction of the likelihood of developing working diseases.

The prior art also knows a number of methods for predicting arterial hypertension in different types of people, including production workers.

A known method for the diagnosis of arterial hypertension in the workplace (AHRM) using single measurements of blood pressure in the workplace [Kobalava Zh.D., Kotovskaya Yu.V., Hirmanov V.N. Blood pressure in research and clinical practice. Moscow, 2004, p. 68]. The disadvantages of this method are: the inability to assess fluctuations in blood pressure during the day; the effect of hypertension of the white coat is not eliminated; the inability to assess blood pressure variability; the inability to assess the daily rhythm of blood pressure.

Also known is a diagnostic method by paired daily monitoring of blood pressure (hereinafter - BPM) [Shevchenko OP, Praskurnichy EA Stress-induced hypertension. M .: Reopharm, 2004, p. 140]. The known method of BPM involves two options for conducting and includes the following diagnostic criteria:

- with the first option, it is necessary to carry out the Smad on a day off and the Smad on a working day; if the level of average daily blood pressure (hereinafter - HELL) is more than 135/85 mm RT. Art. and the difference between the average daily blood pressure obtained on the working day and day off is 6/3 mm RT. Art. and more, then AGRm is diagnosed;

- with the second option, blood pressure monitoring is carried out in working and free time; if the level of average daily blood pressure is more than 135/85 mm Hg and the difference between the average daily blood pressure readings obtained on the working day and day off is 8/5 mm Hg. and more, then AGRm is diagnosed.

However, the known method has several disadvantages:

- requires special expensive equipment (automatic blood pressure monitor), for the methodology it takes a long time (48 hours), which limits the widespread use of the method,

- inconvenient to use,

- inaccurate, since daily monitoring of blood pressure can be carried out on a relatively calm day for the patient, which determines obviously low blood pressure values.

Also known is a method for predicting arterial hypertension in the workplace in persons of operator occupations (RF Patent No. 2371083). According to this method, an increase in systolic blood pressure (SBP) is assessed. At the same time, they create a stressful effect with a 3-minute test “mathematical count”. The test is carried out no earlier than 2 hours after smoking, eating, exercising, no earlier than 3-4 hours after taking the antihypertensive drug, and the test “mathematical count” consists in verbally subtracting the single-digit number 7 from the three-digit 624 with switching attention, s Taking into account the lack of time, critics of work and the test are continued for 3 minutes, with systolic (SBP) and diastolic blood pressure, heart rate being measured at every minute of the load and every minute during the recovery period neny (heart rate) and the increase in CAD and heart rate is calculated by a special formula. If the subject has an initial CAD of more than 130 mm Hg. Art., and in response to a stress test there is an increase in SBP more than 7% and / or an increase in heart rate of more than 10%, then the patient is predicted to have arterial hypertension in the workplace. The method allows to determine arterial hypertension in the workplace of people in operator occupations with a high level of occupational stress during screening studies.

However, this method is not accurate enough, because To obtain the parameters used in forecasting, subjective characteristics are used, such as the test “mathematical calculation”.

Closest to the proposed technical solution is the method described in the article in the journal "Therapist". - 2014. - No. 5. - S. 23-29: Vlasova E.M., Alekseev V.B., Shlyapnikov D.A. "Early diagnosis of conditions predictive of production-related arterial hypertension in workers employed in underground work." According to this method, a medical examination of workers engaged in underground mining in working conditions with industrial noise at a level above the acceptable level is carried out by determining in a blood sample a number of laboratory parameters characterizing pathogenetic links in the mechanism of development of arterial hypertension. And also determine the functional indicator - the state of the vascular endothelium through the establishment of the degree of decrease in growth of the diameter of the brachial artery. Mathematical modeling of the dependence “exposure (noise in the range of 83-94 dB A) - length of service - response (AG)” is carried out to obtain a model of the dependences of the probability of development of a production-induced AH on the level of production noise and work experience.

At the same time, the article states that the level of individual risk of production-induced hypertension increases with the experience and exposure (level) of production factors (noise), and:

1. The symptom complex for the early diagnosis of conditions predictive for the development of production-related arterial hypertension includes: an indicator of the degree of reduction in nightly blood pressure by less than 10%; a decrease in the level of parasympathetic influences on the heart rhythm, an increase in the sensitivity of the rhythm to sympathetic influences; endothelial dysfunction; local thickening of the intima-media complex (CIM) of the common carotid artery; thyroid hyperplasia; hyperglycemia; dyslipidemia; increased homocysteine; high content of nitric oxide.

2. Data from functional studies indicating a deterioration in cardiac risk: with an increase in seniority, the rate of decrease in the endothelial reaction increases compared to the average in men without risk factors, significantly (p = 0.001) increases the thickness of the CMM.

3. The presence of conditions predictive of the development of hypertension has been established: dysfunction of the autonomic system; endothelial dysfunction, atherosclerosis; metabolic syndrome.

The disadvantage of this known method is that there are no elements of identification of the mechanism of development of the risk of hypertension, which reduces the reliability; the assessment of the professional conditionality of the elements of this mechanism is not performed, there is no classification of the obtained results of risk assessment, the probability of the formation of hypertension in individuals with predictors of hypertension is not taken into account, and the applied method for predicting the development of hypertension using mathematical modeling of the exposure – experience – response (AG) relationship does not quantification of severity of hypertension. All this does not ensure the establishment of professional conditionality of prenosological indicators characterizing the mechanism of development of hypertension.

The technical result achieved by the present invention is to enable the quantitative assessment of the professional risk of developing arterial hypertension in workers through the use of advanced information diagnostic criteria characterizing arterial hypertension, while additionally using, along with them, a quantitative scale of professional risk, taking into account at the same time, the likelihood of developing prenosological signs of arterial hype hypertension and the likelihood of developing hypertension in workers with prenosological signs.

The technical result is achieved by the proposed method for assessing occupational health risks associated with the development of arterial hypertension in workers employed in underground mining in working conditions with industrial noise at a level above the permissible level, including medical examination of workers employed in underground mining in labor with industrial noise at a level higher than permissible, by determining in the blood sample the following characterizing pathogenetic The links in the mechanism of the development of arterial hypertension of laboratory parameters: the content of high density lipoproteins, homocysteine, an atherogenic index, and determination of a functional indicator - the state of vascular endothelium through establishing the degree of decrease in growth of the diameter of the brachial artery, and, taking into account deviations of these indicators from the norm, assessing professional risk, while new is that they additionally determine the level of malondialdehyde and the level of antioxidant in a worker’s blood sample activity, carry out the subsequent comparison of all the indicated laboratory and functional indicators with the physiological norm, then for all laboratory indicators with a deviation from the norm, the degree of causal relationship with working conditions is established by calculating the relative risk indicator RR and the etiological share EF of the contribution of factors of working conditions in the development of arterial hypertension and classify these laboratory parameters as professionally determined if they are characterized by RR> 1.5 and EF> 33%, and in taking into account the confirmation for all these laboratory indicators of their professional conditionality determine the probability p _i ¹ deviations from the norm of the state of vascular endothelium in workers; then determine the probability p _i ^{2 the} development of arterial hypertension in workers with deviations from the norm of the state of vascular endothelium; further, the occupational risk R _i ^{AH is} calculated for the health of workers employed in underground mining in working conditions with industrial noise at a level above the permissible value, according to the formula

,

,

where p _i ¹ is the probability of a deviation from the norm of the state of vascular endothelium in workers (the likelihood of the development of prenosological signs of arterial hypertension);

p _i ² - the probability of developing arterial hypertension in workers with deviations from the norm of the state of vascular endothelium (the likelihood of developing arterial hypertension in workers with prenosological signs);

G - severity of arterial hypertension 0,078;

10 - the maximum length of service of employees in underground mining (years);

and the degree of professional risk of developing hypertension in workers is judged on the basis of the following scale:

Degree of risk: Occupational risk: Small - less than 1.0 × 10 ^-3 Average - 1.0 × 10 ^-3 - 5.0 × 10 ^-3 Tall - 5.0 × 10 ^-3 - 1.0 × 10 ^-2 Very tall - more than 1.0 × 10 ^-2

The specified technical result is achieved due to the following.

One of the main tasks of occupational medicine is to prevent the development of diseases of the cardiovascular system in identifying risk factors and their modifications. The optimal, in our opinion, is the analysis of the indicator - the vasomotor function of the brachial artery endothelium, which allows to clarify the degree of risk of hypertension.

The impact of harmful production factors can cause the formation of additional pathogenetic links in the mechanism of development of negative effects. Observations indicate that when exposed to high noise levels (above the permissible), a number of mechanisms develop that underlie cardiovascular system disorders, which, among others, include dyslipidemia [Shapovalova VP, Ryzhova TV, Ryzhov V .M. The state of lipid metabolism when exposed to noise and aluminum dust. Occupational medicine and industrial ecology. 2010; from. 18-20]. Additional elements of the pathogenetic effect of noise (above 80 dBA) include impaired neuroendocrine regulation, free radical oxidation (which is why when implementing the proposed method it is necessary to determine such important laboratory parameters as the level of malondialdehyde and the level of antioxidant activity).

Currently, the dominant role of hypoxia as one of the mechanisms of hypertension due to negative effects on endothelial function has been proven. Hypoxia is the most important pathogenic factor, because is one of the main reasons for the activation of the processes of free radical and peroxidation and, consequently, the development of oxidative stress. Oxidative stress has a harmful effect on vascular function by intensifying the process of lipid peroxidation (lipid peroxidation), which leads to a violation of the regulation of vascular tone, namely, inhibition of the production of nitric oxide and ultimately to an increase in homocysteine levels. Also, as a result of lipid peroxidation, modified (oxidized) lipoproteins are formed, which cause damage to the vascular endothelium. Currently, endothelial dysfunction is recognized as the main predictor of cardiovascular diseases and is considered as an early sign of vascular damage in arterial hypertension. Thus, under conditions of exposure to noise above the normative level, workers form pathogenetic links in the mechanism of AH development, such as dyslipidemia, oxidative stress, dysregulation of vascular tone, which have a damaging effect on the inner wall of blood vessels, which is manifested by a violation of the vasomotor function of the endothelium.

Methods for assessing the functional state make it possible to objectively and correctly assess the degree of various deviations in the state of health. According to modern concepts, the pathophysiological mechanisms of hypertension suggest the involvement of vessels of both muscle and elastic types in them. The condition of the vascular wall in this disease is attracting increasing interest of researchers from the point of view of the promising therapeutic effect and prevention of vascular catastrophes.

It is important to note that the emphasis in studying the structural and functional features of blood vessels is currently placed on the mechanical parameters of the vascular wall, such as the function of the endothelium. The prognostic value of diagnosing conditions, predictive hypertension, is the ability to form an individual forecast based on the results of the proposed method.

Ultrasound scanning allows non-invasive detection of minimal changes in the vascular wall and with great accuracy to identify the initial structural changes in the wall in the form of its thickening, compaction, structural changes.

Due to the fact that the functional diagnostics of workers is carried out by determining an objective indicator - the state of the vascular endothelium, the most reliable and accurate assessment of the state of the vessels as a target organ affected by the production factor determining the professional risk of hypertension is provided. The main role of the endothelium as a neuroendocrine organ is associated with the dilatation of the vascular bed, corresponding to the need of the peripheral muscles and internal organs for adequate blood supply loads. Damage or activation of the endothelium breaks the normal regulatory connections and leads to impaired endothelial function. Thus, endothelial dysfunction can be defined as an imbalance between relaxing and constrictor factors, between anti- and procoagulant mediators or growth factors and their inhibitors.

Endothelial dysfunction, which loses the ability to produce endothelium-dependent relaxing factors, plays a significant role in the pathogenesis of isolated systolic hypertension. Therefore, this proposed indicator will fully reflect the sensitivity of the endothelium to the effects of the production factor for each individual employee.

Due to the fact that when implementing the proposed method, a subsequent comparison of the specified functional indicator with physiological normative value is carried out, the most accurate assessment of individual risk is provided. A normative indicator of the state of vascular endothelium is given in the source of information: American Society of Echocardiography. Touboul P.J., Hennerici M.G., Meairs S. et al. Mannheim intima-media thickness consensus. On behalf of the advisory board of the 3rd Watching the Risk Symposium 2004, 13th European Stroke Conference, Mannheim, Germany, May 14, 2004 // Cerebrovasc Dis. 2004. V. 18. P. 346-349. Touboul P.J., Hennerici M.G., Meairs S. et al. Mannheim Carotid Intima-Media Thickness Consensus (2004-2006) // Cerebrovasc Dis. 2007. V. 23. P. 75-80.

The detection of the employee’s response to the production factor — the impact of noise above the acceptable value — was determined by the deviation of both the functional indicator from the norm and the deviation of the laboratory parameters from the norm.

Given that the proposed method is about assessing occupational health risks, it was important to prove and establish the degree of their causal relationship with working conditions by calculating the relative risk index (RR) and the etiological production share (EF) of the contribution of working conditions factors in the development of arterial hypertension by assigning these deviated laboratory parameters to professionally determined, if they are characterized by RR> 1.5 and EF> 33%. And if at least one of the indicated indicators does not establish the indicated relationship, then a further risk assessment is not performed for the employees, because it will be considered that the development of arterial hypertension in workers employed in underground mining in working conditions with industrial noise at a level above the permissible level is not proven in terms of professional activity.

But in the case of confirmation for absolutely all of the indicated laboratory parameters (the level of malondialdehyde MDA, antioxidant activity of AOA, HDL high density lipoproteins, homocysteine, atherogenicity index) of their professional conditionality, the subsequent determination of the probability p _i ¹ deviations from the norm of the state of the vascular endothelium in workers and the probability p _i ^{2 of the} development of arterial hypertension in workers with deviations from the norm of the state of vascular endothelium with the calculation of occupational risk R _i ^AH the number of workers employed in underground mining in working conditions with industrial noise at a level higher than permissible, according to the formula

,

,

G - severity of arterial hypertension 0,078;

10 - the maximum length of service of employees in underground mining (years).

Moreover, it should be noted that p _i ¹ and p _i ² relate to the likelihood of developing donosological signs of arterial hypertension and the likelihood of developing hypertension in workers with donosological signs, respectively. An indication of the sign "prenosological" indicates that the proposed method determines the early, not yet manifested AH, while the prototype determines only the state predictive for the development of AH, without taking into account the likelihood of AH development in workers with established predictor states.

Using in the method according to the prototype of mathematical modeling does not allow the classification of risk, taking into account the severity of the disease. The use of mathematical modeling in the prototype will allow us to estimate the time and (length of service) of the occurrence of a health disorder and the exposure value of the influencing factor. The implementation of the model, taking into account the severity of hypertension and the likelihood of developing hypertension in workers with established predictor states, will only lead to the bulkiness of the model.

The degree of professional risk of developing arterial hypertension in workers from noise exposure in the proposed method is judged on the basis of the following scale:

Risk degree: Occupational risk: Small - less than 1.0 × 10 ^-3 Average - 1.0 × 10 ^-3 - 5.0 × 10 ^-3 Tall - 5.0 × 10 ^-3 - 1.0 × 10 ^-2 Very tall - more than 1.0 × 10 ^-2

The proposed scale allows you to set the risk of developing hypertension in workers by assessing the indicator as the main predictor of the development of hypertension, and its changes are the result of pathogenetic links in the mechanism of hypertension formation under conditions of noise exposure at a level above the permissible level.

Based on the foregoing, we can conclude that the technical result is achieved due to the totality of operations of the proposed method, their sequence and modes of its implementation.

When implementing the proposed method, the following operations are carried out in the following sequence:

1. At the initial stage, a medical examination of workers engaged in underground mining in working conditions with industrial noise at a level above the permissible level (no more than 80 dBA noise is considered acceptable. And in real conditions of underground mining, a noise level of even 93-94 dBA is recorded ) At the same time, the following laboratory parameters are determined for such workers in a blood sample that characterize the pathogenetic links in the mechanism of development of arterial hypertension: levels of MDA, AOA, HDL; homocysteine, and also determine the index of atherogenicity. Laboratory diagnostics was performed according to standard methods using a PE-5300v spectrophotometer (Ecohim, Russia) and a Konelab 20 biochemical analyzer (ThermoFisher, Finland).

2. Next, a functional indicator is determined - the state of the vascular endothelium through the establishment of the magnitude of the decrease in the increase in diameter of the brachial artery. In the study of endothelial function, the indicator "sensitivity of the brachial artery to a change in the shift to the endothelium" is used. This indicator determines how sensitive the endothelium is to a change in blood flow velocity and how much it retained the ability to regulate the diameter of the vessel. The greater the value of this coefficient, the more sensitive the endothelium to shear stress, the higher the level of regulation of arterial tone, the greater the increase in the diameter of the brachial artery in the sample. Ultrasound assessment of vascular endothelial status is carried out according to the modified Celermajer D.S. methodology. et al. (1992) on a Viamo SSA-640A portable ultrasound scanner (Toshiba medical, Japan) using a 7 MHz linear sensor. The sensitivity of the brachial artery was calculated by the formula:

K = (ΔD / Dο) / (Δτ / το),

where K is the coefficient of sensitivity of the brachial artery to a change in mechanical stimulus,

ΔD is the difference between the diameter of the artery after reocclusion and the initial diameter,

Dο - the initial diameter of the artery,

Δτ is the difference in shear stress on the endothelium after reocclusion and the initial value.

το is the initial shear stress on the endothelium, calculated by the formula:

τ = 4ηV / D,

where η is the viscosity of the blood (on average 0.05 P);

V - maximum blood flow velocity, cm / s;

D is the diameter of the artery, see

Processing of the obtained data is carried out in the environment of the package “Statistica v 10.0, 6.0” (StatSoft, USA), Excel Microsoft WindowsXP 2007, using a software module made in the form of a macro MS Excel.

3. Then carry out the subsequent comparison of all these laboratory parameters with the physiological norm, which is the following:

MDA - 1.8-2.5 μmol / dm ³ .

AOA - 36.2-38.6%.

HDL - 1.42-10 mmol / dm ³ .

Homocysteine - 4.6-12.44 μmol / dm ³ .

The atherogenic index is 1.98-2.51.

Establish indicators with deviations from the norm.

If there is a deviation from the norm, then they conclude that the employee’s body responds to the influence of the production factor - noise.

4. For all laboratory parameters with a deviation from the norm, the degree of causal relationship with working conditions is determined by calculating the relative risk indicator (RR) and by the etiological production share (EF) of the contribution of working conditions factors to the development of arterial hypertension and these laboratory indicators are referred to professionally determined if each of them meets the conditions: RR> 1.5 and EF> 33%. To establish this fact, they use the establishment of the degree of professional conditioning of changes using the Electronic Interactive Directory Directory (edited by Academician of the Russian Academy of Medical Sciences N.F. Izmerov and Prof. E.I. Denisov) (URL: http://neurocomp.ru/cgi- bin / opr / sos / start.py) for calculating the relative risk indicators (RR) using the 95% confidence interval (CI) (to assess the reliability of the data obtained, assessing the confidence interval gives information about the accuracy of the study) and assessing the degree of cause and effect communication violations Vya with work according to the criteria of Guidelines R 2.2.1766-03 “Guidelines for assessing occupational risks to the health of workers. Organizational and methodological foundations, principles and evaluation criteria. ”

5. In the case of confirmation for all the indicated laboratory indicators of their professional conditionality (that is, for each condition RR> 1.5 and EF> 33% are satisfied at the same time), they proceed to the further stages of assessing professional risk. If at least one of the indicated laboratory indicators with a deviation did not show professional conditionality, then it is concluded that the deviations of the indicators are not caused by the impact of working conditions, the professional conditionality of the pathogenetic mechanism of the development of AH is not proved, and the risk assessment does not continue.

6. If all the indicated laboratory indicators with a deviation show professional conditionality, then a subsequent comparison of the functional indicator — the state of the vascular endothelium with the standard value (the norm for it is 10% or more) is carried out. And at the same time, this deviation is used to judge the magnitude of the professional risk to the employee’s health.

7. Determine the probability p _i ¹ deviations from the norm of the state of the vascular endothelium in workers by establishing the ratio of the number of workers with deviations of the determined indicators to the total number of workers examined. In other words, p _i ¹ is the probability of the development of prenosological signs of arterial hypertension in workers.

8. Then, the probability p _i ^{2 of the} development of arterial hypertension in workers with abnormalities in the state of vascular endothelium is determined by establishing the ratio of the number of workers with arterial hypertension and abnormalities in the state of vascular endothelium to the total number of workers with abnormalities in the state of vascular endothelium. In other words, p _i ² is the likelihood of developing hypertension in workers with prenosological signs.

9. Next, calculate the occupational risk R _i ^{AH for the} health of workers employed in underground mining in working conditions with industrial noise at a level above the permissible value, according to the formula

,

,

Where

G is the severity of arterial hypertension 0,078 (the upper limit of the severity of diseases of moderate severity in accordance with the scale of the severity of health disorders specified in the patent of the Russian Federation No. 2368322);

10 - the maximum length of service of employees in underground mining (years), corresponds to the minimum length of service in underground work for the appointment of a preferential pension.

The value of the acceptable risk level (1.0⋅10 ^-3 ) for the health of occupational groups adopted in the Risk Assessment Guide (R 2.1.10.1920-04 “Guide to Health Risk Assessment” was taken as the amount of occupational risk corresponding to a low degree of risk. population when exposed to chemicals polluting the environment ”).

The degree of professional risk of developing hypertension in workers is judged on the basis of the following scale:

Risk degree: Occupational risk: Small - less than 1.0 × 10 ^-3 Average - 1.0 × 10 ^-3 - 5.0 × 10 ^-3 Tall - 5.0 × 10 ^-3 - 1.0 × 10 ^-2 Very tall - more than 1.0 × 10 ^-2

10. Based on the results of the risk value, it is recommended to form risk groups and carry out preventive measures in accordance with the degree of risk:

- In the low-risk group, only preventive measures are recommended aimed at creating a healthy lifestyle, eating behavior. Dynamic monitoring of indicators characterizing the mechanism of development of hypertension, as part of a periodic medical examination.

- In the medium-risk group, in addition to the activities performed for low-risk workers, non-drug therapy (physiotherapy, massage, exercise therapy) is recommended.

- In the high-risk group, recommend self-monitoring of blood pressure (BP), as well as blood pressure control at the health center level; advising a patient on a healthy lifestyle by a cardiologist of a medical organization. Conducting courses of antioxidant and metabolic therapy with a frequency of 1 time in 6 months, lasting 1 month.

- In the very high-risk group, the use of screening studies of indicators with a frequency of 2-3 times a year is recommended. In the early manifestations of the disease - the implementation of preventive programs (drug therapy: courses of antioxidant and metabolic therapy with a frequency of 1 time in 6 months, lasting 1 month and lipid-lowering therapy - statins), aimed at normalizing the predictor indicators characterizing the mechanism of development of hypertension, s Shift control of blood pressure at a pre-medical appointment, the dissemination of knowledge on a healthy lifestyle among workers.

An example of a specific implementation.

To prove the feasibility of implementing the proposed method, determining the diagnostic significance of the proposed laboratory and functional indicators and the conditional risk assessment scale, the employees of underground potash ore mine workings were examined:

- observation group: drivers of mining excavation machines (engine operator), work in conditions of noise load 93-94 dBA (127 men, average age - 36.41 ± 1.0 years, average work experience - 7.3 ± 0.9 years );

- comparison group: workers engaged in professional activities on the surface, working under noise loads not exceeding 80 dBA (57 men, average age - 37.84 ± 2.7 years, average experience - 5.8 ± 1.9 years) .

The working conditions of these workers were evaluated in accordance with the Guidelines for the Hygienic Assessment of the Factors of the Working Environment and the Labor Process. Criteria and classification of working conditions. R 2.2.2006-05. "

The general assessment of working conditions for the employees of the observation group corresponds to class 3.2 (class 2 - by vibration; class 3.1 - by microclimate parameters; parameters of the light environment; class 3.2 - by noise and class 3.3 - by concentration of sylvinite dust in the air of the working area). The categories of a priori occupational risk for workers employed in underground mining are high (intolerable). For workers in the comparison group, working conditions correspond to class 3.1 (the factors are the light environment and microclimate, i.e., no noise).

Group average values of laboratory indicators and a functional indicator characterizing the mechanism of hypertension development in the group of workers exceed the similar indicators of the comparison group (table 1).

The activity levels of antioxidant processes in workers exposed to noise during underground mining are significantly lower than in the comparison group, which indicates the depletion of the resources of the antioxidant system. Oxidative stress has a detrimental effect on vascular function by intensifying the process of lipid peroxidation (LPO), which confirms a significantly increased level of the end product of peroxidation - plasma malondialdehyde: the average MDA content in blood serum in the group was 3.52 ± 0.13 mmol / l, which is significantly 1.3 times higher than similar indicators in workers of the comparison group (p <0.001). A significantly higher atherogenicity index (1.3 times) and a lower HDL content (1.2 times) were found. Violation of the regulation of vascular tone is evidenced by an increase in the activity of homocysteine in the blood serum of workers of the observation group, which has a damaging effect on the inner wall of blood vessels, which is confirmed by a decrease in the increase in the diameter of the brachial artery in the observation group as a result of ultrasound examination.

For workers engaged in underground mining in noise exposure conditions above the standard level, professional dependence of pathogenetic links in the mechanism of AH development, such as dyslipidemia, oxidative stress, impaired regulation of vascular tone and endothelial dysfunction, has been established (table 2).

The probability of formation of pathogenetic links in the mechanism of AH development in the examined group of workers employed in underground mining under conditions of high noise exposure was p _i ¹ = 0.11 for 1 year.

The probability of developing AH in 1 year in workers with prenosological disorders is estimated by the results of epidemiological studies as p _i ² = 0.12.

As a result, the risk value Ri of ^hypertension for the health of workers in the observation group due to hypertension, taking into account the severity, was:

which allows it to be attributed to a high level of risk, if we use the proposed scale of professional risk:

Risk degree: Occupational risk: Small - less than 1.0 × 10 ^-3 Average - 1.0 × 10 ^-3 - 5.0 × 10 ^-3 Tall - 5.0 × 10 ^-3 - 1.0 × 10 ^-2 Very tall - more than 1.0 × 10 ^-2

The employees of the comparison group did not calculate this risk, because professional conditionality for the following laboratory parameters has not been established: antioxidant activity of blood plasma, level of the end product of peroxidation (characterizes the intensification of the process of lipid peroxidation (LPO) of cell membranes) - malondialdehyde of blood plasma, blood homocysteine activity, which characterizes the violation of the regulation of vascular tone, indicators lipid metabolism (HDL cholesterol, atherogenicity index) and the relative increase in the diameter of the brachial artery (characterizes endothelial function).

Employees of the observation group with a specified high risk level of 1-10 ^{-2 are} recommended to regularly monitor blood pressure and conduct courses of antioxidant and metabolic therapy with a frequency of 1 time in 6 months, lasting 1 month.

To justify the accuracy and reliability of the proposed method, workers from the observation group underwent the indicated therapy twice during the year (in March and October). Therapy lasted for one month. At the same time, employees took the following drugs at the recommended age dosage: Vitrum® Antioxidant, Cardionate, Atorvastatin. After a year, this group of workers was again investigated by the proposed method. The risk value of R _i ^AG was 1.2 этом10 ^-3 , which corresponded to an average degree of risk. The reduction in this situation of both the magnitude of professional risk and its degree for these workers proves the legitimacy of the application of the claimed method for assessing the risk of developing hypertension in workers in working conditions with industrial noise at a level above the permissible level.

Thus, the data obtained during the implementation of the proposed method are necessary to solve expert questions about the possibility of continuing to work in this profession and to justify preventive measures aimed at maintaining health.

It should be noted that at present, scales have been developed for assessing the risk of developing cardiovascular diseases (CVD) and their complications (SCORE, FRS), which make it possible to determine the possibility of developing cardiovascular events over 10 years. However, there is evidence that in 74.5% of cases, myocardial infarction develops in people with a low risk (less than 10% on the FRS scale), therefore, identification of the adverse effects of production factors on the risk of professionally caused arterial hypertension in workers is relevant for determining forecasting the risk of development of production-related hypertension and labor forecast. Therefore, the search for new markers of hypertension formation and new diagnostic approaches remains relevant.

Thus, the proposed method has the following advantages over the prototype:

- allows you to determine for workers in conditions of exposure to noise above the acceptable level the professional conditionality of prenosological indicators characterizing the mechanism of development of hypertension;

- quantify the health risk associated with hypertension;

- perform a gradation of health risk due to hypertension to carry out activities to minimize risk.

Claims (8)

A method for assessing occupational health risk associated with the development of arterial hypertension in workers employed in underground mining in working conditions with industrial noise at a level above the acceptable level, including conducting a medical examination of workers employed in underground mining in working conditions with industrial noise at level is higher than permissible, by determining in the blood sample the following characterizing pathogenetic links in the mechanism of development of arterial hypertension Rational indicators: the content of high density lipoproteins, homocysteine, an atherogenic index, and determining a functional indicator - the state of the vascular endothelium by establishing the degree of decrease in the growth of the diameter of the brachial artery, and, taking into account deviations of these indicators from the norm, conducting an occupational risk assessment, characterized in that determine the level of malondialdehyde and the level of antioxidant activity in a worker’s blood sample, and then compare all the specified laboratory and functional indicators with a physiological norm, then for all laboratory indicators with a deviation from the norm, the degree of causal relationship with working conditions is determined by calculating the relative risk indicator RR and the etiological share EF of the contribution of working conditions factors to the development of arterial hypertension and refer these laboratory indicators to professionally determined, if they are characterized by RR> 1.5 and EF> 33%, and if confirmed for all these laboratory parameters, their profession sionic conditionality determine the probability p _i ¹ deviations from the norm of the state of vascular endothelium in workers; then determine the probability p _i ^{2 the} development of arterial hypertension in workers with deviations from the norm of the state of vascular endothelium; further, the occupational risk R _i ^{AH is} calculated for the health of workers employed in underground mining in working conditions with industrial noise at a level above the permissible value, according to the formula

, where p _i ¹ is the probability of deviation from the norm of the state of the vascular endothelium in workers (the likelihood of development of prenosological signs of arterial hypertension) is calculated by establishing the ratio of the number of workers with deviations of the determined indicators to the total number of workers examined; p _i ² - the probability of developing arterial hypertension in workers with deviations from the norm of the state of vascular endothelium (the probability of developing arterial hypertension in workers with prenosological signs) is calculated by establishing the ratio of the number of workers with arterial hypertension and deviations from the norm of the state of vascular endothelium to the total number of workers with deviations from the norm of the state of vascular endothelium; G - severity of arterial hypertension 0,078; 10 - the maximum length of service of employees in underground mining for retirement (years); and the degree of professional risk of developing hypertension in workers is judged on the basis of the following scale: Risk degree Occupational risk Small less than 1.0 × 10 ^-3 Average 1.0 × 10 ^-3 -5.0 × 10 ^-3 Tall 5.0 × 10 ^-3 -1.0 × 10 ^-2 Very tall more than 1.0 × 10 ^-2