KR20040085124A - Human body component analyzer using methods of bioelectrical impedance analysis and bone mineral density measurement - Google Patents

Abstract

PURPOSE: A human body component analyzer is provided to achieve improved accuracy of measurement by measuring the total body mineral mass of a human body through the use of bone mineral density measurement. CONSTITUTION: A human body component analyzer comprises a bio impedance measurement unit for measuring bio impedance through a bioelectrical impedance analysis method; a bone mineral density measurement unit; a weight measurement unit; an input unit(60) for inputting information of object person for measurement; a control unit for obtaining a human body component analysis result by using the total body water calculated from the bio impedance measured by the bio impedance measurement unit, total body mineral mass calculated from the measurement of the bone mineral density measurement unit, and the weight measured by the weight measurement unit; and an output unit for outputting the result of analysis. The bio impedance measurement unit includes a foot electrode and a hand electrode(12).

Description

Human body component analyzer using methods of bioelectrical impedance analysis and bone mineral density measurement}

The present invention relates to a human component analyzer, and more particularly, to a human component analyzer using a bioelectrical impedance analysis method and a bone density measurement method.

Body fat percentage is an important factor in determining the nutritional status of individuals and groups. Recently, obesity patients are rapidly increasing, and the adult disease caused by obesity is also rapidly increasing. Since the criterion for determining obesity is the level of body fat percentage, body fat percentage should be measured to determine the degree of obesity. Body fat measurement in obese patients is necessary not only for assessing health risks but also for setting treatment criteria. In other words, body fat measurements are also necessary to determine a patient's standard weight or to choose exercise and diet. Regular body fat measurements can also help to assess the effects of exercise or diet, the effectiveness of obesity medications, and nutritional status.

On the other hand, as a method of measuring body composition, there is a method of measuring the mass and dimensions of the body such as body mass index, waist circumference, skin thickness, etc., and dual energy X-ray absorptiometry and specific gravity. Underwater weighing, bioelectric impedance analysis, near-infrared interactance, isotope usage, CT, MRI, etc.

Among them, bioelectrical impedance analysis is widely used because of its low cost and harmlessness to human body. It is also used to calculate the fat free mass (FFM) by measuring the amount of body water, and using this to estimate the remaining body composition, that is, the inorganic mass, the amount of protein according to the ratio. However, since the ratio of body water content and lean body mass, and the composition ratio of inorganic mass and protein amount in lean body mass are different according to age, gender, race, and personal health state, the problem of lack of accuracy if it is assumed to be a constant like the conventional method There is.

SUMMARY OF THE INVENTION The present invention has been made to solve the above problems, and an object of the present invention is to obtain the bone mineral mass of the body together with the body water amount by simultaneously measuring the bioelectrical impedance and bone density, and the ratio of body water content and lean body mass and lean body mass. It is to provide a human body component analyzer using a bioelectrical impedance analysis method and a bone density measurement method, by correcting the ratio of the inorganic mass and calculating a more accurate body composition amount.

1 is a schematic perspective view of a human body analyzer according to the present invention.

FIG. 2 is a detailed cross-sectional view taken along the line A-A of FIG. 1, in which quantitative ultrasound is used to measure bone density.

3 is a detailed cross-sectional view taken along line A-A of FIG.

4 is a perspective view of a height and weight scale.

<Description of the symbols for the main parts of the drawings>

10: power generation pole 12: hand electrode

20: Ultrasonic probe

50: load cell 60: input unit, display

70: foot measurement unit

In order to achieve the above object, the human body component analyzer using the bioelectrical impedance analysis method and the bone density measurement method according to the present invention includes a bioimpedance measurement unit for measuring the bioimpedance by the bioelectrical impedance analysis method; Bone density measuring unit; Weight measuring unit; An input unit configured to input information of a subject and perform input for controlling the operation of the device; A controller for calculating a human body component analysis result using the body water amount calculated from the bioimpedance measured by the bioimpedance measuring unit, the inorganic mass calculated from the measured value of the bone density measuring unit, and the weight measured by the weight measuring unit; And an output unit including a display and / or a printer for outputting the analysis result.

Hereinafter, with reference to the accompanying drawings will be described in detail the present invention.

The present invention is a device for more accurately measuring the amount of body water, inorganic mass, protein, body fat, etc. in the human body using the bioelectrical impedance analysis results and bone density measurement results than conventional bioelectrical impedance analysis alone. While the conventional bioelectrical impedance analysis method measures only the body water content, in the present invention, by measuring the inorganic mass of the human body using the bone density measurement method, it is possible to more accurately measure the components of the human body.

As such, the human body analyzer using the bioelectrical impedance analysis method and the bone density measurement method according to the present invention includes a bioimpedance measuring unit, a bone density measuring unit, a weight measuring unit, an input unit, a control unit, and an output unit.

The bioimpedance measurement unit is a part for measuring the bioimpedance by the above-described known bioelectrical impedance analysis method, and preferably includes a power generation electrode 10 and a hand electrode 12.

The bone density measuring unit preferably measures the bone density by quantitative ultrasound or dual energy X-ray method. First, quantitative ultrasonography transmits ultrasonic waves to the calcaneus, tibia, or phalanx, or transmits them to the surface. As a method of obtaining), bone density is measured by measuring the thickness of the soft tissue by using a signal that the ultrasonic wave incident on the skin is reflected back to the bone. Next, the dual energy X-ray absorption method is a method of measuring the bone density of the wrist, finger, calcaneus, spine, femur, or the whole body by generating X-rays of two different energy levels, for example, 50 kVp and 80 kVp.

The bone density measuring unit preferably measures the bone density of the calcaneus (see FIGS. 2 and 3). In the case of using quantitative ultrasound, the bone density measuring unit includes an ultrasonic probe 20 (see FIG. 2). Thus, a device for measuring bone density using the ultrasonic probe 20 is already known. In the case of using the dual energy X-ray absorption method, the bone density measurement unit includes an X-ray generator 30 and an X-ray image detector 40. The X-ray generator 30 includes an X-ray tube 32 and a high pressure generator 34, and the X-ray image detector 40 includes a scintillator 42 and a lens 44. ), And a charge coupled device (CCD) 46 (see FIG. 3). Devices for measuring bone density using these components are already known.

The weight measuring unit is preferably a load cell 50 or a weight scale.

The input unit is a part for inputting information of a subject, such as age and gender, and performing input for controlling the operation of the device.

The controller controls the measurement process and the output, and analyzes and calculates the obtained measurement data to calculate a result. Herein, the analysis, calculation, and result calculation will be described in detail. The body mass calculated from the bioimpedance measured by the bioimpedance measuring unit, the inorganic mass calculated from the measured value of the bone density measuring unit, and the weight measuring unit By using the measured weight, it refers to the calculation of the human body component analysis result. Here, the human body component analysis result is preferably at least one selected from the group consisting of lean body mass, body fat mass, body fat percentage, protein amount, and bone density change trend data over time.

The output is comprised of a display 60 and / or a printer for outputting the results.

The human body analyzer according to the present invention further includes a height measuring unit, and preferably, the weight measuring unit and the height measuring unit are integrally formed.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings.

1 schematically illustrates a human body analyzer according to a preferred embodiment of the present invention. This is a foot measuring unit 70 for inserting a foot by the subject, a part of the subject holding the foot by inserting the foot, and a hand electrode 12 for measuring the bioelectrical impedance, a subject such as age and gender. And an input unit 60 for inputting information and performing input for controlling the operation of the device, and a display 60 showing measurement and analysis results. In this case, the input unit 60 adopts a touch screen method so that an input is performed on the display 60. This input method is only one example, and other types of inputs are also possible.

The foot measuring unit 70 has a structure as shown in FIG. 2 or 3 according to the bone density measuring unit of the calcaneus. FIG. 2 shows a case where quantitative ultrasound is used as a bone density measurement method, and FIG. 3 shows a case where a dual energy X-ray absorption method is used as a bone density measurement method.

In the case of using quantitative ultrasonography as a method for measuring bone density (see FIG. 2), the ultrasound probe 20 is adhered to the left and right sides of the subject's foot 1 using its own matching layer or a separate bonding medium, and the calcaneus The transmission rate SOS and the damping characteristic BUA can be measured. In addition, one or more foot electrodes 10 of one foot and one or more foot electrodes 10 of the other foot may be paired with the hand electrode 12 to measure bioelectrical impedance. A load cell 50 is installed below the support plate 72 supporting the feet 1 of the subject to measure the weight of the subject. One or more load cells 50 may be installed in each foot. In this case, there may be no load cell 50 in the foot measuring unit 70, and in this case, a separate scale or height and weight scale 52 is provided. In the case of having a separate weight scale, the measured weight value is transmitted to the human body analyzer of FIG. 1 by wire or wirelessly, and the height value is directly input by the input unit 60. When a separate height and weight scale 52 (FIG. 4) is provided, the measured height and weight values are transmitted to the human body analyzer of FIG. 1 by wire or wirelessly.

In the case of using the dual energy X-ray absorption method as a bone density measurement method (see FIG. 3), X-rays having energy levels of 50 kVp and 80 kVp are generated to measure bone density of calcaneus. In addition, the part related to the power generation pole 10 and the load cell 50 and the weight scale or the height / weight scale 52-related portion are the same as the case by the above quantitative ultrasonic method. Reference number 80 indicates the basic body of the human body analyzer.

Hereinafter, in the present invention, how various values such as lean body mass, body fat mass, body fat percentage, protein amount, and bone density change trend data over time are calculated will be described.

Total body water (TBW) can be calculated as follows through body impedance measurement.

TBW = H ² / Z

When using the impedance of each part, get as follows.

TBW = A (H ² / Za ₁ + H ² / Za ₂ ) + B × H ² / Zb + C (H ² / Zc ₁ + H ² / Zc ₂ )

Where A, B, and C are constants, and H is height, Za ₁ , Za ₂ , Zb, Zc ₁ , and Zc ₂ are impedances of respective parts.

The ratio of total body water (TBW) and fat free mass (FFM) has a value of 0.70 to 0.76, which will be referred to as WLR (Water Lean Ratio).

FFM = TBW / WLR

Body weight (BM) is expressed as the sum of body mass (FM) and fat free mass (FFM).

BM = FM + FFM

The fat free mass (FFM) may be expressed as a sum of total body mineral mass (TMM), total body protein mass (TPM) and total body water (TBW).

FFM = TMM + TPM + TBW

In the conventional method of measuring only bioimpedance, the ratio of inorganic mass (TMM) and protein amount (TPM) is assumed as a constant. However, in the present invention, the inorganic mass (TMM) is calculated using the result of bone density measurement. You can find out more about FFM. The ratio of the inorganic mass (TMM) and the amount of protein (TPM) and the ratio of the inorganic mass (TMM) and the lean body mass (FFM) can be found using the underwater weight measurement method which is a standard measurement method of body composition.

Using dual-energy X-ray methods, bone mineral content (BMC) can be measured to determine the inorganic mass (TMM) (Comparison of methods for assessing body composition changes over 1y in postmenopausal women, p401, 2000). .

TMM = BMC × 1.279

When using quantitative ultrasound, the inorganic mass (TMM) is as follows.

TMM = f (H, SOS, BUA)

Here, H is height, SOS is speed of sound, and BUA is broadband ultrasound attenuation.

Bone Mineral Density (BMD) is used for the diagnosis of osteoporosis, and the World Health Organization (WHO) suggests that the BMD mean and standard deviation of the standard population (applicable gender, age 20s) is used. Obtain a T-score as follows, and determine whether or not osteoporosis according to this value.

T-score = (PV-YAV) / SD _YA

Where PV is the BMD measurement of the patient, YAV is the mean BMD of the standard population, and SD _YA is the BMD standard deviation of the standard population.

T-scores can also be obtained using quantitative ultrasound in addition to BMD. In this case, instead of bone density (BMD), a value obtained by combining ultrasonic transmission rate (SOS) and attenuation amount (BUA), for example, bone quality index (BQI) is used.

BQI = f (SOS, BUA)

According to the WHO standard, it can be determined according to the T-score value as shown in Table 1 below.

Measures Classification T> -1.0 normal -1.0 ≥ T> -2.5 Low bone mass (osteopenia) -2.5 ≥ T Osteoporosis

Typically, bone density peaks between the 20s and 30s and then gradually decreases with age. In women, menopause shows a sharp decline immediately after menopause and increases bone mineral density when treated with Hormone Replacement Therapy (HRT) or bisphosphonates.

Obesity has long been known as a protective factor in osteoporosis in postmenopausal women (Arch. Intern. Med., Vol. 136, p298-304, 1976; Geriatrics, Vol. 44, p45-54, 1989). This is due to the effects of estrogens produced by conversion in adipose tissue (J. Clin. Endocrinol. Metab., Vol. 36, p207-218, 1973) and the effects of sex hormone-binding globulin (SHBG). Horm. Meta.Res., Vol. 22, p303-306, 1990).

Using this, body fat percentage (body fat mass / weight) can be used to predict changes in bone density, and changes in bone density (BMD) or bone quality index (BQI) can be calculated using the following formula.

BQI (m) = BQI (0) + s (F, T) × m

Where m is the time until the forecast time in months, BQI (m) is the BQI after m months, BQI (0) is the current BQI, and s (F, T) is the percent body fat (F) And BQI change coefficient according to treatment method (T).

In this manner, the measurement result of the bioimpedance together with the bone density measurement result may be used to estimate a trend of bone density change with time or age.

As described above, the present invention can obtain a more accurate analysis result than the analysis of the human body components using only the conventional bioimpedance by using the bone density measurement technology and the bioimpedance measurement technology, more accurate and specific bone density than the conventional bone density measurement technology It is also possible to estimate the variation of.

In addition, the two measurement techniques can be combined into one device for quick and easy measurement results.

Although the present invention described above has been described in detail only with respect to the specific examples described, it will be apparent to those skilled in the art that various modifications and changes are possible within the technical spirit of the present invention, and such modifications and modifications belong to the appended claims. will be.

Claims (8)

A bioimpedance measuring unit measuring a bioimpedance by a bioelectrical impedance analysis method; Bone density measuring unit; Weight measuring unit; An input unit configured to input information of a subject and perform input for controlling the operation of the device; A controller for calculating a human body component analysis result using the body water amount calculated from the bioimpedance measured by the bioimpedance measuring unit, the inorganic mass calculated from the measured value of the bone density measuring unit, and the weight measured by the weight measuring unit; And An output unit comprising a display and / or a printer for outputting the analysis result; Human component analyzer using a bioelectrical impedance analysis method and a bone density measurement method comprising a. The method of claim 1, The bioimpedance measuring unit is a human body component analyzer using a bioelectrical impedance analysis method and a bone density measurement method comprising a power generation electrode and a hand electrode. The method of claim 1, The bone density measuring unit is a human component analyzer using a bioelectrical impedance analysis method and a bone density measurement method characterized in that for measuring the bone density of calcaneus. The method of claim 1, The bone density measuring unit is a human body component analyzer using a bioelectrical impedance analysis method and a bone density measurement method characterized in that using a quantitative ultrasonic method. The method of claim 1, The bone density measuring unit is a human body component analyzer using a bioelectrical impedance analysis method and a bone density measurement method characterized in that using the dual energy X-ray absorption method. The method of claim 1, The body weight analyzer using a bioelectrical impedance analysis method and a bone density measurement method, characterized in that the load cell or the weight scale. The method of claim 1, The human body component analysis result is at least one selected from the group consisting of lean body mass, body fat mass, body fat percentage, protein amount, and bone density change trend data over time. The method of claim 1, And a height measuring unit, wherein the weight measuring unit and the height measuring unit are integrally formed.