Single prediction equation for bioelectrical impedance analysis in adults aged 20--94 years

Overweight Is an Independent Risk Factor for Reduced Lung Volumes in Myotonic Dystrophy Type 1

Background

In this large observational study population of 105 myotonic dystrophy type 1 (DM1) patients, we investigate whether bodyweight is a contributor of total lung capacity (TLC) independent of the impaired inspiratory muscle strength.

Methods

Body composition was assessed using the combination of body mass index (BMI) and fat-free mass index. Pulmonary function tests and respiratory muscle strength measurements were performed on the same day. Patients were stratified into normal (BMI < 25 kg/m²) and overweight (BMI ≥ 25 kg/m²) groups. Multiple linear regression was used to find significant contributors for TLC.

Results

Overweight was present in 59% of patients, and body composition was abnormal in almost all patients. In overweight patients, TLC was significantly (p = 2.40×10⁻³) decreased, compared with normal-weight patients, while inspiratory muscle strength was similar in both groups. The decrease in TLC in overweight patients was mainly due to a decrease in expiratory reserve volume (ERV) further illustrated by a highly significant (p = 1.33×10⁻¹⁰) correlation between BMI and ERV. Multiple linear regression showed that TLC can be predicted using only BMI and the forced inspiratory volume in 1 second, as these were the only significant contributors.

Conclusions

This study shows that, in DM1 patients, overweight further reduces lung volumes, as does impaired inspiratory muscle strength. Additionally, body composition is abnormal in almost all DM1 patients.

How does nutritional state change during a subacute admission? Findings and implications for practice

BACKGROUND/OBJECTIVES

Nutritional status influences patients' clinical and functional outcomes. The aims were to identify changes in nutritional state during subacute care and associated participant characteristics.

SUBJECTS/METHODS

A longitudinal study was undertaken with consecutive patients admitted to subacute care wards during a 3-month period. Participants were recruited under a waiver of consent to reflect the usual demographic. Change in classification (malnourished, at risk of malnutrition, well nourished) of the full Mini Nutritional Assessment (full MNA) between admission and discharge was the primary outcome. Weight (kg), mid-arm and calf circumference (cm) change were secondary outcomes. Hand grip strength (kg) and fat-free mass (kg) (assessed using bioelectrical impedance analysis) were measured for a consenting subgroup.

RESULTS

Participants (n=248, 36.7% male) had a median age of 80 years and a length of stay of 17 days. On admission, 29.1% were classified as malnourished. By discharge, nutritional classification remained stable for 62.0% of participants (n=132), declined for 10.3% (n=22) and improved for 27.7% (n=59, including 52.5% malnourished on admission). Impaired cognition (odds ratio (OR)=0.169, P=0.002) and higher full MNA score at admission (OR=0.870, P=0.001) reduced odds of improvement in full MNA. There was no change in hand grip strength (n=46), but there was a decline in mean fat-free mass (-1.1 kg, 95% confidence interval: -0.1 to -2.2 kg, P=0.043, n=24).

CONCLUSIONS

Multidisciplinary care supports the nutritional state of most patients admitted to subacute care. Those with cognitive impairments or at risk of malnutrition were less likely to demonstrate improvement and may benefit from more intensive or tailored nutritional care.

Postoperative Changes in Body Composition After Pancreaticoduodenectomy Using Multifrequency Bioelectrical Impedance Analysis

BACKGROUND

Nutritional status is one of the most important clinical determinants of outcome after surgery. The aim of this study was to compare changes in the body composition of patients undergoing pancreaticoduodenectomy (PD), distal gastrectomy (DG), or total gastrectomy (TG).

METHODS

The parameters of body composition were measured using multifrequency bioelectrical impedance analysis with an inBody 720 (Biospace Inc. Tokyo. Japan) in 60 patients who had undergone PD (n = 18), DG (n = 30), or TG (n = 12). None of the patients had recurrence or were treated with chemotherapy. Changes between the preoperative data and results and those obtained 12 months after surgery were evaluated.

RESULTS

Twelve months after surgery, the body weight change in the PD group was significantly lower than in the TG and DG groups (-1.2 ± 3.8 vs -7.4 ± 4.4 and -4.0 ± 3.2 kg, respectively; p < 0.01 vs TG, p < 0.05 vs DG). The body weight change correlated with the fat mass change in all groups.

CONCLUSIONS

The type and extent of surgery has a different effect on long-term body weight and body composition. Bioelectric impedance analysis can be used to assess body composition and may be useful for nutritional assessment in patients who have undergone these surgeries.

Sarcopenia in patients undergoing maintenance hemodialysis: incidence rate, risk factors and its effect on survival risk

BACKGROUND

Sarcopenia is a degenerative syndrome mainly characterized by the atrophy of skeletal muscle, along with the decrease of muscle strength and function. However, there are currently few studies concerning sarcopenia in patients undergoing maintenance hemodialysis dialysis (MHD). This study was aimed to investigate the incidence of sarcopenia in MHD patients and its influencing factors, as well as its impact on survival risk.

METHOD

All 131 MHD patients enrolled in our study were tested with bioelectrical impedance analysis (BIA) and grip strength. Demographic data was collected and anthropometric measurement and laboratory examination were conducted.

RESULTS

The total incidence of sarcopenia within the 131 MHD patients was 13.7% and the incidence of sarcopenia in patients over 60 years was 33.3%. The dialysis duration, with or without diabetes, serum phosphorus and pre-albumin levels of sarcopenic patients were significantly different from those of non-sarcopenicones; the modified quantitative subjective global assessment (MQSGA) scores of sarcopenic patients were higher than those without sarcopenia. Multivariate analysis showed that dialysis duration, diabetes and serum phosphorus level were independent risk factors for sarcopenia in MHD patients. Kaplan-Meier survival analysis showed a one-year survival of 88.9% in sarcopenic patients, which was significantly lower than non-sarcopenic patients.

CONCLUSION

The incidence of sarcopenia in MHD patients was high and increased gradually with age. Dialysis duration, diabetes, serum phosphorus level and malnutrition predisposed the patients to sarcopenia. One-year follow-up found that the mortality risk of sarcopenic patients was higher than that of non-sarcopenic patients.

Screening for physical inactivity among adults: the value of distance walked in the six-minute walk test. A cross-sectional diagnostic study

CONTEXT AND OBJECTIVES

Accelerometry provides objective measurement of physical activity levels, but is unfeasible in clinical practice. Thus, we aimed to identify physical fitness tests capable of predicting physical inactivity among adults.

DESIGN AND SETTING

Diagnostic test study developed at a university laboratory and a diagnostic clinic.

METHODS

188 asymptomatic subjects underwent assessment of physical activity levels through accelerometry, ergospirometry on treadmill, body composition from bioelectrical impedance, isokinetic muscle function, postural balance on a force platform and six-minute walk test. We conducted descriptive analysis and multiple logistic regression including age, sex, oxygen uptake, body fat, center of pressure, quadriceps peak torque, distance covered in six-minute walk test and steps/day in the model, as predictors of physical inactivity. We also determined sensitivity (S), specificity (Sp) and area under the curve of the main predictors by means of receiver operating characteristic curves.

RESULTS

The prevalence of physical inactivity was 14%. The mean number of steps/day (≤ 5357) was the best predictor of physical inactivity (S = 99%; Sp = 82%). The best physical fitness test was a distance in the six-minute walk test and ≤ 96% of predicted values (S = 70%; Sp = 80%). Body fat > 25% was also significant (S = 83%; Sp = 51%). After logistic regression, steps/day and distance in the six-minute walk test remained predictors of physical inactivity.

CONCLUSION

The six-minute walk test should be included in epidemiological studies as a simple and cheap tool for screening for physical inactivity.

[Nutritional status assessment in Geriatrics: Consensus declaration by the Spanish Society of Geriatrics and Gerontology NutritionWork Group]

Ongoing population ageing is one of the factors influencing the increase in the prevalence of undernutrition, as elderly people are a vulnerable group due to their biological, psychological and social characteristics. Despite its high prevalence, undernutrition is underdiagnosed in the geriatric sphere. For this reason, the aim of this consensus document is to devise a protocol for geriatric nutritional assessment. A multidisciplinary team has been set up within the Spanish Society of Geriatrics and Gerontology (in Spanish Sociedad Española de Geriatría y Gerontología [SEGG]) in order to address undernutrition and risk of undernutrition so that they can be diagnosed and treated in an effective manner. The MNA-SF is a practical tool amongst the many validated methods for nutritional screening. Following suspicion of undernutrition, or after establishing the presence of undernutrition, a full assessment will include a detailed nutritional history of the patient. The compilation of clinical-nutritional and dietetic histories is intended to help in identifying the possible risk factors at the root of a patient's undernutrition. Following this, an anthropometric assessment, combined with laboratory data, will describe the patient's physical and metabolic changes associated to undernutrition. Currently, the tendency is for further nutritional assessment through the use of non-invasive techniques to study body composition in association with functional status. The latter is an indirect index for nutritional status, which is very interesting from a geriatrician's point of view. To conclude, correct nutritional screening is the fundamental basis for an early undernutrition diagnosis and to assess the need for nutritional treatment. In order to achieve this, it is fundamental to foster research in the field of nutritional geriatrics, in order to expand our knowledge base and to increasingly practice evidence-based geriatrics.

Body composition and basal metabolic rate in Hidradenitis Suppurativa: a Danish population-based and hospital-based cross-sectional study

BACKGROUND

Several studies have suggested an association between Hidradenitis Suppurativa (HS) and obesity. Obesity is often expressed as Body Mass Index (BMI). However, BMI lacks information on body composition. General obesity is a predictor of health status and cardiovascular risk, but body composition (e.g. abdominal fat) may be more so. Basal metabolic rate (BMR) is an expression of resting metabolism and may serve as a complementary tool when assessing the possibly underlying metabolism behind a persons' body composition.

OBJECTIVE

To investigate the body composition and basal metabolic rate in individuals with HS compared with healthy controls.

METHODS

We performed a cross-sectional study on both a hospital-based and population-based HS group and compared with controls using Bioelectrical Impedance Analysis to assess body composition.

RESULTS

We identified a hospital-based HS group of 32 hospital HS patients, a population-based HS group of 430 population HS patients, and 20 780 controls. Age- and sex-adjusted analyses showed a 10.12% (P < 0.0001) significantly higher fat percentage in the hospital-based HS group and 3.11% (P < 0.0001) significantly higher fat percentage for the population-based HS group compared to controls. Correspondingly, the HS groups had a lower muscle percentage (P < 0.0001) and lower bone mass percentage (P < 0.0001). Furthermore, visceral fat rating (P < 0.0001), Body Mass Index (P < 0.0001), waist circumference (P < 0.0001), and Waist/Hip Ratio (P < 0.0001) was significantly higher in HS patients compared with controls. Additionally, age and sex-adjusted analyses showed a higher predicted estimate of BMR for the HS groups compared with controls (154.56 kcal/day (95% CI 54.96-254.16) (P = 0.0031) for the hospital-based HS group, and 82.63 kcal/day (95%CI 59.70-105.56) (P < 0.0001) for the population-based HS group).

CONCLUSION

Hidradenitis Suppurativa is associated with a high fat percentage, high visceral fat, and low muscle percentage adding to the morbidity of HS. The higher predicted estimate of basal metabolic rate (BMR) in HS patients may reflect a dysfunctional metabolism contributing to the high-fat-body composition.

Feasibility of bioelectrical impedance analysis in persons with severe intellectual and visual disabilities

BACKGROUND

Body composition measurements provide important information about physical fitness and nutritional status. People with severe intellectual and visual disabilities (SIVD) have an increased risk for altered body composition. Bioelectrical impedance analysis (BIA) has been evidenced as a reliable and non-invasive method to asses body composition in healthy persons and various patient populations; however, currently, there is no feasible method available to determine body composition in people with SIVD. In this study, therefore, we aimed to assess the feasibility of BIA measurements in persons with SIVD.

METHODS

In 33 participants with SIVD and Gross Motor Functioning Classification System (GMFCS) Scale I, II, III, or IV, two BIA measurements were sequentially performed employing Resistance and Reactance in Ohm and fat-free mass (FFM) in kg as outcome variables, utilizing the Bodystat(®) QuadScan 4000. Feasibility was considered sufficient if ≥ 80% of the first measurement was performed successfully. Agreement between two repeated measurements was determined by using the paired t-test and Intraclass Correlation Coefficient (ICC; two way random, absolute agreement). Bland-Altman analyses were utilized to determine limits of agreement (LOAs) and systematic error. Agreement was considered acceptable if LOAs were <10% of the mean of the first measurement.

RESULTS

The first BIA measurements were completed successfully in 88% of the participants. The paired t-test demonstrated no significant differences in Resistance, Reactance, and FFM between BIA Measurements 1 and 2 (P=0.140, 0.091, and 0.866). ICC was 0.965 (95% CI: 0.922-0.984) for Resistance; 0.858 (95% CI: 0.705-0.934) for Reactance; and 0.992 (95% CI: 0.982-0.996) for FFM. LOAs expressed as a percentage of the mean of Measurement 1 were 6.1% for Resistance, 17.6% for Reactance, and 3.8% for FFM.

CONCLUSIONS

The results of this study suggest that BIA measurements seem to be feasible in persons with SIVD. Although these results require confirmation in a more extensive sample of persons with SIVD, the findings of this study are an important first step in the assessment of applicability of BIA measurements for non-invasive monitoring of physical fitness and nutritional status of persons with SIVD.

Prevalence of type 2 diabetes and its association with measures of body composition among African residents in the Netherlands--The HELIUS study

AIMS

To compare type 2 diabetes prevalence among three ethnic groups resident in the Netherlands: Ghanaians, African Surinamese and Dutch origin. Secondly, to determine the contribution of measures of body composition to ethnic differences in type 2 diabetes.

METHODS

Baseline data from Ghanaian (n=1873), African Surinamese (n=2189) and Dutch (n=2151) origin participants of the HELIUS study (aged 18-70 years) were analyzed. Type 2 diabetes was determined according to the WHO criteria. Logistic regression tested ethnic differences in type 2 diabetes and the contribution of body fat percentage and waist-to-hip ratio.

RESULTS

Among men, type 2 diabetes prevalence was higher in Ghanaians (14.9%) than in African Surinamese (10.4%) and Dutch (5.0%). Among women, type 2 diabetes prevalence in Ghanaian (11.1%) was higher than in Dutch (2.3%), but similar to African Surinamese (11.5%). After adjusting for age, body fat percentage and waist-to-hip ratio, the odds ratios for having type 2 diabetes were 1.55 (95% CI: 1.12-2.15) for Ghanaian men compared with African Surinamese and 4.19 (95% CI: 2.86-6.12) compared with Dutch. Among women these odds ratios were 0.94 (95% CI: 0.70-1.26) and 4.78 (95% CI: 2.82-8.11).

CONCLUSIONS

The higher prevalence of type 2 diabetes among Ghanaian compared with African Surinamese men suggests a need to distinguish between African descent populations when assessing their type 2 diabetes risk. The higher odds for type 2 diabetes among Ghanaians cannot be attributed to differences in body composition. Further research on the contribution of lifestyle factors as well as genetic and epigenetic factors is needed to identify the reasons for the observed disparities.

Cross-mode bioelectrical impedance analysis in a standing position for estimating fat-free mass validated against dual-energy x-ray absorptiometry

Bioelectrical impedance analysis (BIA) is commonly used to assess body composition. Cross-mode (left hand to right foot, Z(CR)) BIA presumably uses the longest current path in the human body, which may generate better results when estimating fat-free mass (FFM). We compared the cross-mode with the hand-to-foot mode (right hand to right foot, Z(HF)) using dual-energy x-ray absorptiometry (DXA) as the reference. We hypothesized that when comparing anthropometric parameters using stepwise regression analysis, the impedance value from the cross-mode analysis would have better prediction accuracy than that from the hand-to-foot mode analysis. We studied 264 men and 232 women (mean ages, 32.19 ± 14.95 and 34.51 ± 14.96 years, respectively; mean body mass indexes, 24.54 ± 3.74 and 23.44 ± 4.61 kg/m2, respectively). The DXA-measured FFMs in men and women were 58.85 ± 8.15 and 40.48 ± 5.64 kg, respectively. Multiple stepwise linear regression analyses were performed to construct sex-specific FFM equations. The correlations of FFM measured by DXA vs. FFM from hand-to-foot mode and estimated FFM by cross-mode were 0.85 and 0.86 in women, with standard errors of estimate of 2.96 and 2.92 kg, respectively. In men, they were 0.91 and 0.91, with standard errors of the estimates of 3.34 and 3.48 kg, respectively. Bland-Altman plots showed limits of agreement of -6.78 to 6.78 kg for FFM from hand-to-foot mode and -7.06 to 7.06 kg for estimated FFM by cross-mode for men, and -5.91 to 5.91 and -5.84 to 5.84 kg, respectively, for women. Paired t tests showed no significant differences between the 2 modes (P > .05). Hence, cross-mode BIA appears to represent a reasonable and practical application for assessing FFM in Chinese populations.

Quadriceps muscle strength, radiographic knee osteoarthritis and knee pain: the ROAD study

Background

The objective of this study was to clarify the association of quadriceps muscle strength with knee pain using a large-scale, population-based cohort of the Research on Osteoarthritis/osteoporosis Against Disability (ROAD) study.

Methods

From the 2566 subjects at the third visit of the ROAD study, the present study analyzed 2152 subjects who completed radiographic examinations and measurements of muscle strength and mass (690 men and 1462 women; mean age, 71.6 ± 12.2 years). Knee pain was assessed by an experienced orthopedist. Knee osteoarthritis (OA) was defined according to Kellgren-Lawrence (KL) grade. Quadriceps muscle strength and muscle mass at the lower limbs were measured by the Quadriceps Training Machine (QTM-05F, Alcare Co., Ltd. Tokyo, Japan) and the Body Composition Analyzer MC-190 (Tanita Corp., Tokyo, Japan), respectively.

Results

Quadriceps muscle strength and weight bearing index (WBI: quadriceps muscle strength by weight) were significantly associated with knee pain after adjustment for age and body mass index, whereas grip strength and muscle mass at the lower limbs were not. The significant association of quadriceps muscle strength with knee pain was independent of radiographic knee OA.

Conclusion

The present cross-sectional study showed an independent association of quadriceps muscle strength with knee pain.

Electronic supplementary material

The online version of this article (doi:10.1186/s12891-015-0737-5) contains supplementary material, which is available to authorized users.

Fat-free mass prediction equations for bioelectric impedance analysis compared to dual energy X-ray absorptiometry in obese adolescents: a validation study

Background

In clinical practice, patient friendly methods to assess body composition in obese adolescents are needed. Therefore, the bioelectrical impedance analysis (BIA) related fat-free mass (FFM) prediction equations (FFM-BIA) were evaluated in obese adolescents (age 11–18 years) compared to FFM measured by dual-energy x-ray absorptiometry (FFM-DXA) and a new population specific FFM-BIA equation is developed.

Methods

After an overnight fast, the subjects attended the outpatient clinic. After measuring height and weight, a full body scan by dual-energy x-ray absorptiometry (DXA) and a BIA measurement was performed. Thirteen predictive FFM-BIA equations based on weight, height, age, resistance, reactance and/or impedance were systematically selected and compared to FFM-DXA. Accuracy of FFM-BIA equations was evaluated by the percentage adolescents predicted within 5 % of FFM-DXA measured, the mean percentage difference between predicted and measured values (bias) and the Root Mean Squared prediction Error (RMSE). Multiple linear regression was conducted to develop a new BIA equation.

Results

Validation was based on 103 adolescents (60 % girls), age 14.5 (sd1.7) years, weight 94.1 (sd15.6) kg and FFM-DXA of 56.1 (sd9.8) kg. The percentage accurate estimations varied between equations from 0 to 68 %; bias ranged from −29.3 to +36.3 % and RMSE ranged from 2.8 to 12.4 kg. An alternative prediction equation was developed: FFM = 0.527 * H(cm)²/Imp + 0.306 * weight - 1.862 (R² = 0.92, SEE = 2.85 kg). Percentage accurate prediction was 76 %.

Conclusions

Compared to DXA, the Gray equation underestimated the FFM with 0.4 kg (55.7 ± 8.3), had an RMSE of 3.2 kg, 63 % accurate prediction and the smallest bias of (−0.1 %). When split by sex, the Gray equation had the narrowest range in accurate predictions, bias, and RMSE. For the assessment of FFM with BIA, the Gray-FFM equation appears to be the most accurate, but 63 % is still not at an acceptable accuracy level for obese adolescents. The new equation appears to be appropriate but await further validation. DXA measurement remains the method of choice for FFM in obese adolescents.

Trial registration

Netherlands Trial Register (ISRCTN27626398).

Longitudinal assessment of physical activity in women undergoing Roux-en-Y gastric bypass

BACKGROUND

Patients undergoing bariatric surgery do not seem to increase objectively measured physical activity (PA) after surgery, despite substantial weight loss. The aims of the present study were (i) to objectively characterize 3 months pre-surgery to 9 months postsurgery PA and sedentary behavior changes in women undergoing Roux-en-Y gastric bypass (RYGB) using tri-axial accelerometers and (ii) to examine associations between pre-surgery versus postsurgery PA and sedentary behavior with anthropometric measures taken in home environment.

METHODS

Fifty-six women, with an average pre-surgery body mass index (BMI) of 37.6 (SD 2.6) and of age 39.5 years (SD 5.7), were recruited at five Swedish hospitals. PA was measured for 1 week by the Actigraph GT3X+ accelerometer, and anthropometric measures were taken at home visits 3 months pre-surgery and 9 months postsurgery, thus limiting seasonal effects.

RESULTS

Average BMI loss, 9 months postsurgery, was 11.7 (SD 2.7) BMI units. There were no significant pre- to postsurgery differences in PA or sedentary behavior. However, pre-surgery PA showed negative association with PA change and positive association with postsurgery PA. Adjustments for pre-surgery BMI had no impact on these associations.

CONCLUSIONS

No significant differences were observed in objectively measured changes in PA or time spent sedentary from 3 months pre-surgery to 9 months postsurgery among women undergoing RYGB. However, women with higher pre-surgery PA decreased their PA postsurgery while women with lower pre-surgery PA increased their PA.

The Association of Handgrip Strength and Type 2 Diabetes Mellitus in Six Ethnic Groups: An Analysis of the HELIUS Study

We investigated whether ethnic differences in handgrip strength, a marker of poor muscle strength and quality, is a potential cause of ethnic disparities in type 2 diabetes mellitus. We included 2086 Dutch, 2216 South Asian Surinamese, 2084 African Surinamese, 1786 Ghanaian, 2223 Turkish and 2199 Moroccan origin participants from the HELIUS study. We analyzed ethnic differences in handgrip strength, and its association with type 2 diabetes mellitus using logistic regression analyses adjusted for socio-demographic factors, body composition and lifestyle factors. Additionally, we investigated whether handgrip strength explained the ethnic differences in type 2 diabetes mellitus. We found that handgrip strength differed significantly across ethnic groups. After full adjustment, we found an inverse association with type 2 diabetes mellitus (OR 0.95; 95% CI 0.92-0.97) that did not differ substantially between ethnic groups, men and among women, and lean and overweight individuals. The association was not affected by the measure used to define type 2 diabetes mellitus, but was attenuated by exclusion of people with known diabetes. The ethnic differences in type 2 diabetes mellitus were not explained by handgrip strength (e.g. the OR for the South Asian Surinamese vs. Dutch changed from 5.03; 3.69-6.68 to 4.87; 3.57-6.65). In conclusion, we found large ethnic differences in handgrip strength and a consistent association of low handgrip strength with prevalent type 2 diabetes mellitus. This suggests that handgrip strength may be investigated as a target for intervention or a marker to identify people at risk of type 2 diabetes mellitus.

Smartphone-Based Bioelectrical Impedance Analysis Devices for Daily Obesity Management

Current bioelectric impedance analysis (BIA) systems are often large, cumbersome devices which require strict electrode placement on the user, thus inhibiting mobile capabilities. In this work, we developed a handheld BIA device that measures impedance from multiple frequencies (5 kHz~200 kHz) with four contact electrodes and evaluated the BIA device against standard body composition analysis systems: a dual-energy X-ray absorptiometry (DXA) system (GE Lunar Prodigy, GE Healthcare, Buckinghamshire, UK) and a whole-body BIA system (InBody S10, InBody, Co. Ltd, Seoul, Korea). In the study, 568 healthy participants, varying widely in body mass index, age, and gender, were recruited at two research centers: the Samsung Medical Center (SMC) in South Korea and the Pennington Biomedical Research Center (PBRC) in the United States. From the measured impedance data, we analyzed individual body fat and skeletal muscle mass by applying linear regression analysis against target reference data. Results indicated strong correlations of impedance measurements between the prototype pathways and corresponding InBody S10 electrical pathways (R = 0.93, p < 0.0001). Additionally, body fat estimates from DXA did not yield significant differences (p > 0.728 (paired t-test), DXA mean body fat 29.45 ± 10.77 kg, estimated body fat 29.52 ± 12.53 kg). Thus, this portable BIA system shows a promising ability to estimate an individual's body composition that is comparable to large stationary BIA systems.

Association of serum vitamin D with change in weight and total body fat in a German cohort of older adults

We examined the association of baseline serum 25-hydroxyvitamin D (25(OH)D) with change in weight and total body fat in a cohort of community-dwelling older adults from Southern Germany. A total of 735 participants of the population-based KORA-Age Study (2009-2012), aged 65-90 years, were followed for 2.9±0.1 years. Body fat was assessed with bioelectrical impedance analysis. Linear and multinomial logistic models, adjusted for baseline covariables, were used to examine the association of 25(OH)D with percentage weight and body fat change during follow-up. 25(OH)D levels were not associated with overall weight change or body fat loss. Higher 25(OH)D levels were associated with a lower likelihood of having gained >3% of body fat in women but not in men. As we cannot exclude residual confounding by outdoor physical activity and diet, our results are not sufficient to support a causal role of 25(OH)D in the etiology of obesity in Caucasian older adults.

Body mass index and waist circumference are not good surrogate indicators of adiposity in psychogeriatric patients

OBJECTIVE

to assess the utility of body mass index (BMI) and waist circumference (WC) as surrogate indicators of adiposity with respect to the total body fat estimated with bioimpedance analysis in psychogeriatric patients.

METHODS

Anthropometric and hand-to-foot bioimpedance measurements were performed according to standard procedures in a sample of 128 psychogeriatric patients (87 males, 41 females). WC cutoffs proposed by the International Diabetes Federation were used to define abdominal obesity. Z-scores of fat and fat-free mass indices (Z-FMI and Z-FFMI) were calculated.

RESULTS

Males with WC values below the cutoff were normal weight, and showed normal levels of FM and low FFM (Z-FFMI below 1.5 SD). Males with WC values above the cutoff were overweight, showed high levels of FM (Z-FMI: 1.34 SD) and a slight depletion of FFM (Z-FFMI: -0.59 SD). In females with WC values below the cutoff, BMI was close to 20 kg/m(2) and both FM and FFM were depleted (Z-FMI: -0.7 SD; Z-FFMI: -1.76 SD). In females with WC above the cutoff, the average BMI was 25.6 kg/m(2) , Z-FMI was 0.48 SD, and Z-FFMI was -0.56 SD.

CONCLUSIONS

Our results indicate that it is necessary to establish age and sex-specific BMI and WC cutoffs, and also highlight the importance of focusing on body composition analysis to ensure an accurate nutritional diagnosis in older-adults and in psychogeriatric patients.

Metabolic and cardiovascular responses during aquatic exercise in water at different temperatures in older adults

PURPOSE

The aim of this study was to investigate the physiological responses during upper-body aquatic exercises in older adults with different pool temperatures.

METHOD

Eleven older men (aged 65 years and older) underwent 2 identical aquatic exercise sessions that consisted of 3 upper-body exercises using progressive intensities (30, 35, and 40 metronome beat · min(- 1)) on separate visits. Water temperatures for the visits were 28°C (cold water [CW]) and 36°C (hot water [HW]), and water depth ranged from 1.2 m to 1.4 m. Measurements for heart rate (HR), blood pressure (BP), oxygen consumption (VO2), and rate of perceived exertion (RPE) were compared between the CW and HW conditions.

RESULTS

The comparison between temperatures showed a higher HR response during exercise in HW, particularly when participants exercised at the highest intensities. During a 30-min postexercise period in resting conditions, HR was statistically significantly higher for the HW condition compared with the CW condition, with a large effect size (15.9%, d = 1.23). Systolic and diastolic BPs were found to be lower for the HW condition ( - 7.2%, d = - 0.60; - 10.1%, d = - 0.65), while VO2 and RPE showed no differences. The effect size between double products (HR · systolic BP) for the 2 conditions was small (CW = 8,649 ± 1,287, HW = 9,340 ± 1,672; d = 0.36), suggesting similar myocardial oxygen requirements.

CONCLUSION

This study showed that HR response was higher in an HW condition for older men. Warmer environments may add additional stressors to the body, which may impact training strategies and should be considered when estimating the effort of performing aquatic exercise.

Low Recent Protein Intake Predicts Cancer-Related Fatigue and Increased Mortality in Patients with Advanced Tumor Disease Undergoing Chemotherapy

Cancer patients, in general, suffer from anorexia hence diminished nutritional intake. In a prospective observational study, we investigated the impact of recent energy and protein intake on cancer-related fatigue and 6-month mortality in patients undergoing chemotherapy. Recent protein and energy intake was assessed by 24-h recall in 285 patients. Cancer-related fatigue was determined by Brief Fatigue Inventory, and fat free mass index (FFMI) was assessed with bioelectrical impedance analysis. Symptoms with the validated German version of European Organization for Research and Treatment of Cancer Quality of Life Core Questionnaire (30 questions) and 6-month mortality was documented. Risk factors of cancer-related fatigue and predictors of mortality were investigated with logistic regression analysis and stepwise Cox regression analysis, respectively. Low protein intake (<1 g/kg body weight) was found in 66% of patients, who were characterized by higher age, weight, and body mass index. Recent protein intake emerged as the strongest contributor to cancer-related fatigue followed by nausea/vomiting, insomnia, and age. Reduced protein intake, male sex, number of comorbidities, and FFMI were identified as significant predictors for increased 6-month mortality. In conclusion, a low recent protein intake assessed by 24-h recall is associated with a more than twofold higher risk of cancer-related fatigue and 6-month mortality. Every effort should be taken to assess and guarantee proper nutritional intake in patients undergoing chemotherapy.

Circulating inflammatory miRNA signature in response to different doses of aerobic exercise

While moderate acute exercise has been associated with strong anti-inflammatory mechanisms, strenuous exercise has been linked to deleterious inflammatory perturbations. It is therefore fundamental to elucidate the mechanisms that regulate the exercise-induced inflammatory cascade. Information on novel regulators such as circulating inflammatory microRNAs (c-inflammamiRs) is incomplete. In this study, we evaluated the response of a panel of c-inflammamiRs to different doses of acute aerobic exercise. We first studied the exercise-induced inflammatory cascade in serum samples of nine active middle-aged males immediately before and after (0 h, 24 h, 72 h) 10-km, half-marathon, and marathon races. Next, we analyzed the circulating profile of 106 specific c-inflammamiRs immediately before) and after (0 h, 24 h) 10-km (low inflammatory response) and marathon (high inflammatory response) races. Analysis of classical inflammatory parameters revealed a dose-dependent effect of aerobic exercise on systemic inflammation, with higher levels detected after marathon. We observed an increase in miR-150-5p immediately after the 10-km race. Levels of 12 c-inflammamiRs were increased immediately after the marathon (let-7d-3p, let-7f-2-3p, miR-125b-5p, miR-132-3p, miR-143-3p, miR-148a-3p, miR-223-3p, miR-223-5p, miR-29a-3p, miR-34a-5p, miR-424-3p, and miR-424-5p). c-inflammamiRs returned to basal levels after 24 h. Correlation and in silico analyses supported a close association between the observed c-inflammamiR pattern and regulation of the inflammatory process. In conclusion, we found that different doses of acute aerobic exercise induced a distinct and specific c-inflammamiR response, which may be associated with control of the exercise-induced inflammatory cascade. Our findings point to c-inflammamiRs as potential biomarkers of exercise-induced inflammation, and hence, exercise dose.

Predicting body composition using foot-to-foot bioelectrical impedance analysis in healthy Asian individuals

Background

The objectives of this study were to develop a regression model for predicting fat-free mass (FFM) in a population of healthy Taiwanese individuals using standing foot-to-foot bioelectrical impedance analysis (BIA) and to test the model’s performance in predicting FFM with different body fat percentages (BF%).

Methods

We used dual-energy X-ray absorptiometry (DXA) to measure the FFM of 554 healthy Asian subjects (age, 16–75 y; body mass index, 15.8–43.1 kg/m²). We also evaluated the validity of the developed multivariate model using a double cross-validation technique and assessed the accuracy of the model in an all-subjects sample and subgroup samples with different body fat levels.

Results

Predictors in the all-subjects multivariate model included height²/impedance, weight, year, and sex (FFM = 13.055 + 0.204 weight + 0.394 height²/Impedance – 0.136 age + 8.125 sex (sex: Female = 0, Male = 1), r² = 0.92, standard error of the estimate = 3.17 kg). The correlation coefficients between predictive FFM by BIA (FFM_BIA) and DXA-measured FFM (FFM_DXA) in female subjects with a total-subjects BF%_DXA of <20 %, 20 %–30 %, 30 %–40 % and >40 % were r = 0.87, 0.90, 0.91, 0.89, and 0.94, respectively, with bias ± 2SD of 0.0 ± 3.0 kg, −2.6 ± 1.7 kg, −1.5 ± 2.8 kg, 0.5 ± 2.7 kg, and 2.0 ± 2.9 kg, respectively. The correlation coefficients between FFM_BIA and FFM_DXA in male subjects with a total-subjects BF%_DXA of <10 %, 10 %–20 %, 20 %–30 %, and >30 % were r = 0.89, 0.89, 0.90, 0.93, and 0.91, respectively, with bias ± 2SD of 0.0 ± 3.2 kg, −2.3 ± 2.5 kg, −0.5 ± 3.2 kg, 0.4 ± 3.1 kg, and 2.1 ± 3.2 kg, respectively.

Conclusions

The standing foot-to-foot BIA method developed in this study can accurately predict FFM in healthy Asian individuals with different levels of body fat.

Fat-free mass and its predictors in Huntington's disease

The causes of weight loss in Huntington's disease (HD) are not entirely clear. The aim was to identify risk factors that are associated with a loss of metabolically active tissues, i.e. fat-free mass. A consecutive cohort of non-diabetic HD participants (manifest HD, n = 43; CAG: mean 43.6.0 ± 3.6; preHD, n = 10; CAG: mean 41.4 ± 1.4) and 36 healthy controls was recruited. Twenty-five HD participants were early-stage HD (UHDRS Total Functional Capacity [TFC] stages I and II), 12 mid-stage HD (TFC stage III), and 6 participants were in late-stage HD (TFC stages IV and V). Food intake, basic metabolic rate and glucose homeostasis were assessed. In addition, fat-free mass was determined using bioelectric impedance analysis, and leptin, insulin and ghrelin as key metabolic regulators. Sex ratio and age were similar in HD participants (71 % women; age 50.6 ± 10.9) and controls (66 % women; age 46.4 ± 14.5). Body mass index (BMI) was lower in HD participants than controls (median 24.1 vs. 25.9, p = 0.04). However, fat-free mass and basic metabolic rate were not statistically different between groups and showed no association with disease burden. In controls and HD participants, leptin was the most important predictor of fat-free mass. While BMI was lower in HD participants, fat-free mass was similar to controls with leptin as its most important predictor. Leptin levels and fat-free mass measurements using bioelectric impedance analysis may be good screening tools to identify HD patients at risk for weight loss.

Body composition and all-cause mortality in subjects older than 65 y

BACKGROUND

A low or high body mass index (BMI) has been associated with increased mortality risk in older subjects without taking fat mass index (FMI) and fat-free mass index (FFMI) into account. This information is essential because FMI is modulated through different healthcare strategies than is FFMI.

OBJECTIVE

We aimed to determine the relation between body composition and mortality in older subjects.

DESIGN

We included all adults ≥65 y old who were living in Switzerland and had a body-composition measurement by bioelectrical impedance analysis at the Geneva University Hospitals between 1990 and 2011. FMI and FFMI were divided into sex-specific quartiles. Quartile 1 (i.e., the reference category) corresponded to the lowest FMI or FFMI quartile. Mortality data were retrieved from the hospital database, the Geneva death register, and the Swiss National Cohort until December 2012. Comorbidities were assessed by using the Cumulative Illness Rating Scale.

RESULTS

Of 3181 subjects included, 766 women and 1007 men died at a mean age of 82.8 and 78.5 y, respectively. Sex-specific Cox regression models, which were used to adjust for age, BMI, smoking, ambulatory or hospitalized state, and calendar time, showed that body composition did not predict mortality in women irrespective of whether comorbidities were taken into account. In men, risk of mortality was lower with FFMI in quartiles 3 and 4 [HR: 0.78 (95% CI: 0.62, 0.98) and 0.64 (95% CI: 0.49, 0.85), respectively] but was not affected by FMI. When comorbidities were adjusted for, FFMI in quartile 4 (>19.5 kg/m(2)) still predicted a lower risk of mortality (HR: 0.72; 95% CI: 0.54, 0.96).

CONCLUSIONS

Low FFMI is a stronger predictor of mortality than is BMI in older men but not older women. FMI had no impact on mortality. These results suggest potential benefits of preventive interventions with the aim of maintaining muscle mass in older men. This trial was registered at clinicaltrials.gov as NCT01472679.

Association among body composition, muscle performance and functional autonomy in older adults

Introduction Decrease in muscle mass and increase in body fat are important changes that occur with aging. Strength decline and worse resistance to fatigue can lead to a decreased functional autonomy of the elderly. Objective The present study aimed to verify the existence of a relationship between body composition, muscle strength, lower limbs fatigue and functional autonomy in active elderly women. Materials and methods The sample consisted of 29 elderly women with a mean age of 68.2 (± 7.3) years. Body composition was analyzed by total and segmental bioelectrical impedance. Muscle fatigue was assessed using electromyography, through the analysis of median frequency and root mean square during a 60-second sustained isometric knee extension contraction, at 50% of the maximum voluntary isometric contraction. Functional autonomy was assessed by using the Latin American Development Group for Maturity (GDLAM) protocol. Results There were significant correlations between height and strength (r = 0.49), age and lean body mass (r = -0.42), body fat percentage (BF%) and GDLAM tests (r = 0.39-0.41). The lean body mass was positively correlated with strength (r = 0.55), but not with resistance to fatigue. Conclusion The lean body mass of the analyzed sample was found to be associated with the performance on the maximum strength test, but not with the performance on the resistance to fatigue test. This shows that these two parameters (strength and fatigue) are independent of one another. Elderly women with higher BF% showed worse performance on the GDLAM tests. This evidences that individuals with high adiposity levels tend to have a more limited functional autonomy.

Development of a single-frequency bioimpedance prediction equation for fat-free mass in an adult Indigenous Australian population

BACKGROUND/OBJECTIVES

To describe the development of a single-frequency bioimpedance prediction equation for fat-free mass (FFM) suitable for adult Aboriginal and Torres Strait Islander peoples with and without diabetes or indicators of chronic kidney disease (CKD).

SUBJECTS/METHODS

FFM was measured by whole-body dual-energy X-ray absorptiometry in 147 adult Indigenous Australians. Height, weight, body circumference and resistance were also measured. Adults with and without diabetes and indicators of CKD were examined. A random split sample with internal cross-validation approach was used to predict and subsequently validate FFM using resistance, height, weight, age and gender against measured FFM.

RESULTS

Among 147 adults with a median body mass index of 31 kg/m(2), the final model of FFM was FFM (kg)=0.432 (height, cm(2)/resistance, ohm)-0.086 (age, years)+0.269 (weight, kg)-6.422 (if female)+16.429. Adjusted R(2) was 0.94 and the root mean square error was 3.33 kg. The concordance was high (rc=0.97) between measured and predicted FFM across a wide range of FFM (31-85 kg).

CONCLUSIONS

In the context of the high burden of diabetes and CKD among adult Indigenous Australians, this new equation for FFM was both accurate and precise and based on easily acquired variables (height, weight, age, gender and resistance) among a heterogeneous adult cohort.

Accuracy of plantar electrodes compared with hand and foot electrodes in fat-free-mass measurement

This paper investigates the measurement of fat-free mass (FFM) by bioimpedance using foot-to-foot impedancemeters (FFI) with plantar electrodes measuring the foot-to-foot resistance R34 and hand-to-foot medical impedancemeters. FFM measurements were compared with corresponding data using Dual X-ray absorptiometry (DXA). Equations giving FFM were established using linear multiple regression on DXA data in a first group of 170 subjects. For validation, these equations were used on a second group of 86 subjects, and FFM were compared with DXA data; no significant difference was observed. The same protocol was repeated, but using electrodes on the right hand and foot in standing position to measure the hand to-foot resistance R13. Mean differences with DXA were higher for R13 than for R34. Effect of electrode size and feet position on resistance was also investigated. R34 decreased when electrode area increased or if feet were moved forward. It decreased if feet were moved backward. A proper configuration of contact electrodes can improve measurement accuracy and reproducibility of FFI.

The theory and fundamentals of bioimpedance analysis in clinical status monitoring and diagnosis of diseases

Bioimpedance analysis is a noninvasive, low cost and a commonly used approach for body composition measurements and assessment of clinical condition. There are a variety of methods applied for interpretation of measured bioimpedance data and a wide range of utilizations of bioimpedance in body composition estimation and evaluation of clinical status. This paper reviews the main concepts of bioimpedance measurement techniques including the frequency based, the allocation based, bioimpedance vector analysis and the real time bioimpedance analysis systems. Commonly used prediction equations for body composition assessment and influence of anthropometric measurements, gender, ethnic groups, postures, measurements protocols and electrode artifacts in estimated values are also discussed. In addition, this paper also contributes to the deliberations of bioimpedance analysis assessment of abnormal loss in lean body mass and unbalanced shift in body fluids and to the summary of diagnostic usage in different kinds of conditions such as cardiac, pulmonary, renal, and neural and infection diseases.

New reference values for body composition by bioelectrical impedance analysis in the general population: results from the UK Biobank

BACKGROUND

Low fat-free mass (FFM) is a risk factor for morbidity and mortality in elderly and patient populations. Therefore, measurement of FFM is important in nutritional assessment. Bioelectrical impedance analysis (BIA) is a convenient method to assess FFM and FFM index (FFMI; FFM/height(2)). Although reference values have been established for individuals with normal body weight, no specific cutoff values are available for overweight and obese populations. Also, limited studies accounted for the age-related decline in FFM.

OBJECTIVE

To determine BMI- and age-specific reference values for abnormal low FFM(I) in white-ethnic men and women free of self-reported disease from the general population.

DESIGN

The UK Biobank is a prospective epidemiological study of the general population from the United Kingdom. Individuals in the age category 45 to 69 years were analyzed. In addition to body weight, FFM and FFMI were measured using a Tanita BC-418MA. Also, self-reported chronic conditions and ethnic background were registered, and lung function was assessed using spirometry.

RESULTS

After exclusion of all individuals with missing data, nonwhite ethnicity, self-reported disease, body mass index (BMI) less than 14 or 36 kg/m(2) or higher, and/or an obstructive lung function, reference values for FFM and FFMI were derived from 186,975 individuals (45.9% men; age: 56.9 ± 6.8 years; BMI: 26.5 ± 3.6 kg/m(2); FFMI 18.3 ± 2.4 kg/m(2)). FFM and FFMI were significantly associated with BMI and decreased with age. Percentiles 5, 10, 25, 50, 75, 90, and 95 were calculated for FFM, FFMI, and fat mass (index), after stratification for gender, age, and BMI.

CONCLUSIONS

Using the UK Biobank dataset, new reference values for body composition assessed with BIA were determined in white-ethnic men and women aged 45 to 69 years. Because these reference values are BMI specific, they are of broad interest for overweight and obese populations.

Inverse relationship between "a body shape index" (ABSI) and fat-free mass in women and men: Insights into mechanisms of sarcopenic obesity

BACKGROUND & AIMS

Sarcopenic obesity may be defined by a high fat to fat-free mass (FM/FFM) ratio. Skeletal muscle may be negatively influenced by the pro-inflammatory milieu associated with visceral fat, while the loading effect induced by a heavier body mass index (BMI) may enhance muscle anabolism. Recently, a new anthropometric measure based on waist circumference (A Body Shape Index, ABSI) was developed. In this study we have assessed the predictive power of ABSI on the FFM index (FFMI), a surrogate marker of lean mass.

METHODS

Standard anthropometric parameters and ABSI as well as body composition data (fat and fat-free mass determined by bioelectrical impedance analysis) were assessed in 111 female and 89 male overweight/obese subjects, with no clinically significant co-morbidities. Groups with higher- or lower-ABSI were identified according to median values of this index.

RESULTS

In women and men, ABSI did not correlate with BMI, while multiple linear regression indicated that BMI (β-coefficients: 0.62 and 0.77, respectively) and ABSI (β-coefficients: -0.26 and -0.22, respectively) independently predicted FFMI (multiple R: 0.72 and 0.83, respectively, P < 0.001). Men and women with lower-ABSI exhibited significantly greater FFMI than the higher-ABSI groups for comparable values of BMI. In men, ABSI was correlated positively with C-reactive protein (CRP) (R = 0.30; P < 0.05) and negatively with the reciprocal of insulin (R = 0.28; P < 0.05), an index of insulin sensitivity. FM/FFM ratio significantly (P < 0.01) correlated with CRP (R = 0.31) in women only.

CONCLUSIONS

ABSI, a recently introduced marker of abdominal adiposity, may contribute to define the risk of sarcopenia in overweight/obese individuals.

Prevalence of sarcopenia among healthy ambulatory subjects: the sarcopenia begins from 45 years

BACKGROUND AND AIMS

Sarcopenia has been indicated as a reliable marker of frailty and poor prognosis among the oldest individuals. There are only few data on sarcopenia in healthy general population. We evaluated the prevalence of sarcopenia and its association with functional and clinical status in a population of healthy ambulatory subjects over 45 years living at home, in Paris (France).

METHODS

This study was conducted selecting all ambulatory participants (n = 1,445) aged 45 years and older from October 2008 to September 2011, consulting in the Institute of Physiology (Institut de Jaeger) from Paris (France) for a functional and muscular evaluation, and did not have limitations to moderate physical exercise. All were healthy people. All subjects performed a medical examination, associated with evaluation of muscle mass (body composition assessment using dual-energy X-ray absorptiometry) and of muscle function (by hand grip strength). Diagnosis of sarcopenia required the documentation of low muscle mass with low muscle strength according to the current international consensus definition of sarcopenia.

RESULTS

From 1,421 participants (553 males and 868 females) definitively enrolled, 221 subjects (135 females and 86 males) (15.5 %) were identified as sarcopenic. Results from multivariate logistic regression models showed that sarcopenia was inversely associated with BMI with those participants with BMI higher than 22 kg/m(2) showing a lower risk of sarcopenia relative to those with BMI less than 21 kg/m(2) (OR 0.72; 95 % CI 0.60-0.91). Similarly, probability of sarcopenia was lower among subjects involved in leisure physical activities for 3 h or more per week (OR 0.45; 95 % CI 0.24-0.93). According to the category of age [45-54; 55-64; 65-74; 75-84 and 85 years or more], the prevalence of sarcopenia in women increase from 9.1; 12.7; 14.5; 19.4; to 33.3 %, respectively. For the men, the percentage of sarcopenia increase with aging from 8.6; 15.6; 13.6; 63.8 to 45.5 %, respectively.

CONCLUSIONS

The present study suggests that among healthy ambulatory subjects over 45 years living at home, sarcopenia is frequent, even to the youngest subjects of the studied population, taking place from 9 % from 45 years, until 64.3 % for the subjects over 85 years. Our findings support the hypothesis that muscle mass and function are associated with BMI and physical activity, whatever the age of the subject.

Pain, Work-related Characteristics, and Psychosocial Factors among Computer Workers at a University Center

[Purpose] Complaint of pain is common in computer workers, encouraging the investigation of pain-related workplace factors. This study investigated the relationship among work-related characteristics, psychosocial factors, and pain among computer workers from a university center. [Subjects and Methods] Fifteen subjects (median age, 32.0 years; interquartile range, 26.8-34.5 years) were subjected to measurement of bioelectrical impedance; photogrammetry; workplace measurements; and pain complaint, quality of life, and motivation questionnaires. [Results] The low back was the most prevalent region of complaint (76.9%). The number of body regions for which subjects complained of pain was greater in the no rest breaks group, which also presented higher prevalences of neck (62.5%) and low back (100%) pain. There were also observed associations between neck complaint and quality of life; neck complaint and head protrusion; wrist complaint and shoulder angle; and use of a chair back and thoracic pain. [Conclusion] Complaint of pain was associated with no short rest breaks, no use of a chair back, poor quality of life, high head protrusion, and shoulder angle while using the mouse of a computer.

The Korean urban rural elderly cohort study: study design and protocol

Background

Korea is one of the fastest aging countries and is expected to become a super-aged society within 12 years. The Korean Urban Rural Elderly (KURE) study was developed to evaluate the epidemiological characteristics and establish the prevention and management of major disorders of the elderly in Korea.

Methods/Design

The KURE study is a community-based prospective cohort study on health, aging, and common geriatric disorders of Korean elderly persons aged at least 65 years. To construct a cohort reflecting both urban and rural areas, we selected 2 representative communities in the country. To establish multidisciplinary approaches to geriatric health, this study was performed by researchers in the divisions of geriatrics, preventive medicine, endocrinology, and sociology. The baseline examinations began in 2012; the study will follow more than 4,000 elderly Koreans over 10 years. The first and second follow-up health examinations will be performed every 4 years. Every 2 years after each health examination, inter-assessment interview will be conducted to improve participant retention.

Discussion

The KURE study will provide longitudinal epidemiologic data on health, aging, and common geriatric disorders of the elderly in Korea. This is a comprehensive, multidisciplinary study of the elderly with respect to biological, physical, socio-economic, and environmental factors. The results of this study will contribute to improve public health and welfare policies for the aging society in Korea.

Muscle performance, body fat, pain and function in the elderly with arthritis

Objective:

To correlate muscule performance, body composition, pain and joint function in elderly people with gonarthrosis.

Method:

21 elderly patients were submitted to bioelectrical impedance analysis, dynamometry associated with electromyographic (EMG) evaluation of isometric knee extension, in addition to pain assessment by the Numeric Pain Intensity Scale and function assessment, by the Western Ontario and McMaster Universities (WOMAC) Osteoarthritis (OA) questionnaire. Correlations were checked by the Pearson's correlation coefficient.

Results:

The sample characteristics were mean age 67.36 ± 4.21 years old, body fat percentage 40.57±6.15%, total WOMAC score 43.27 ± 16.32%, and maximum strength 19.95 ± 6.99 kgF. Pain during movement showed a statistical association with WOMAC physical activity domain (r = 0.47) and its general score (r = 0.51); pain intensity at night presented association with WOMAC stiffness domain (r = 0.55), in addition to the negative correlation with the slope values of the Medium Frequency of the EMG signal (r = - 0.57).

Conclusion:

pain intensity is correlated to functional incapacity in elderly people with knee OA and to a greater expression of fatigue in EMG signal. Levels of Evidence III, Study of non consecutive patients

Exercise habits during middle age are associated with lower prevalence of sarcopenia: the ROAD study

SUMMARY

The present cross-sectional study investigated the prevalence of sarcopenia and clarified its associated factors in 1,000 elderly participants of Japanese population-based cohorts. Exercise habit in middle age was associated with low prevalence of sarcopenia in older age, suggesting that it is a protective factor against sarcopenia in older age.

INTRODUCTION

The present study investigated the prevalence of sarcopenia using the European Working Group on Sarcopenia in Older People (EWGSOP) definition, and clarified the association of sarcopenia with physical performance in the elderly participants of Japanese population-based cohorts of the Research on Osteoarthritis/osteoporosis Against Disability (ROAD) study.

METHODS

We enrolled 1,000 participants (aged ≥65 years) from the second visit of the ROAD study who had completed assessment of handgrip strength, gait speed, and skeletal muscle mass measured by bioimpedance analysis. Presence of sarcopenia was determined according to the EWGSOP algorithm. Information collected included exercise habits in middle age.

RESULTS

Prevalence of sarcopenia was 13.8 % in men and 12.4 % in women, and tended to be significantly higher according to increasing age in both sexes. Factors associated with sarcopenia, as determined by logistic regression analysis, were chair stand time (odds ratio [OR], 1.09; 95 % confidence interval [CI], 1.04-1.14), one-leg standing time (OR, 0.97; 95 % CI, 0.96-0.99), and exercise habit in middle age (OR, 0.53; 95 % CI, 0.31-0.90). Exercise habit in middle age was associated with low prevalence of sarcopenia in older age. Furthermore, linear regression analysis revealed that exercise habits in middle age were significantly associated with grip strength (P < .001), gait speed (P < .001), and one-leg standing time (P = .005) in older age.

CONCLUSIONS

This cross-sectional study suggests that exercise habit in middle age is a protective factor against sarcopenia in older age and effective in maintaining muscle strength and physical performance in older age.

Development of an equation for estimating appendicular skeletal muscle mass in Japanese older adults using bioelectrical impedance analysis

AIM

Bioelectrical impedance analysis has been reported to have high reliability and accuracy in assessing body composition. However, equations for estimating appendicular skeletal muscle mass are population-specific, and few have been developed for older Japanese adults. Thus, the purpose of the present study was to develop and validate an estimate equation for appendicular skeletal muscle mass using bioelectrical impedance analysis.

METHODS

A total of 250 older adults aged 65 years and older participated in this study. Appendicular skeletal muscle mass was measured using dual-energy X-ray absorptiometry, and bioelectrical resistance was measured using a multifrequency bioelectrical impedance analyzer. Multiple regression analysis was applied to derive sex-specific estimation formulae using bioelectrical impedance analysis, and a Bland-Altman analysis was used to test agreement.

RESULTS

The cross-validation results showed that the slopes and intercepts of the regression lines were approximately one and zero, respectively, and the coefficients of determination and standard errors of the estimate of the newly developed equations were similar between the two groups. Thus, the single sex-specific equations were developed using all participants as follows. Men: appendicular skeletal muscle mass=0.197 × (impedance index) +0.179 × (weight) -0.019 (R(2)  =0.87, standard error of the estimate=0.98 kg). Women: appendicular skeletal muscle mass=0.221 × (impedance index) +0.117 × (weight) +0.881 (R(2)  =0.89, standard error of the estimate=0.81 kg).

CONCLUSION

These new equations offer a valid option for assessing appendicular skeletal muscle mass in older Japanese adults.