New Reference Values for Body Composition by Bioelectrical Impedance Analysis in the General Population: Results From the UK Biobank

BackgroundLow 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/height²). 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.ObjectiveTo 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.DesignThe 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.ResultsAfter exclusion of all individuals with missing data, nonwhite ethnicity, self-reported disease, body mass index (BMI) less than 14 or 36 kg/m² 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/m²; FFMI 18.3 ± 2.4 kg/m²). 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.ConclusionsUsing 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.     

Joint association of body mass index and central obesity with cardiovascular events and all-cause mortality in prediabetic population: A prospective cohort study

ObjectiveTo assess the joint association of body mass index (BMI) and central obesity with cardiovascular events and all-cause mortality in prediabetic population.MethodsAltogether 18,703 participants with prediabetes completed follow-up between June 2006 and December 2015 were included in the analyses. Prediabetes was defined as fasting plasma glucose level 5.6–6.9 mmol/L, and without history of diabetes or currently use of hypoglycemic agents. Participants were classified according to the baseline status of BMI as well as the absence/presence of central obesity. We examined these associations in men and women separately.ResultsThe mean age was 51.5 ± 11.1 years, and 85.6% (N = 16,002) were male. During a median follow up of 9.0 (interquartile range 8.7–9.2) years, 848 and 88 major CV events occurred in men and women, respectively. Besides, 1111 men and 89 women died. Compared with men of BMI 22–23.9 kg/m² and without central obesity, the risk of CV events was increased among men with higher BMI and central obesity (HR 1.32 (95% CI: 1.05–1.67) for BMI 24–27.9 kg/m² and 1.31 (1.03–1.66) for BMI ≥ 28 kg/m², respectively); and the risk of all-cause mortality was the lowest among men of BMI 24–27.9 kg/m² but without central obesity (0.75, 0.61–0.92). We found no such association in women.ConclusionAmong men with prediabetes, both BMI and waist circumference should be included when evaluating the risks of major CV events and mortality. Measurement of adiposity constitutes a simple and cost-effective strategy to identify those at high-risk population in prediabetes.     

Fat-Free Mass Index as a Surrogate Marker of Appendicular Skeletal Muscle Mass Index for Low Muscle Mass Screening in Sarcopenia

ObjectivesWe aimed to examine the relationship between the fat-free mass index (FFMI; FFM/height²) and appendicular skeletal muscle mass index (ASMI; ASM/height²), measured using both bioelectrical impedance analysis (BIA) and dual-energy X-ray absorptiometry (DXA), and investigate the effects of age and obesity. We also evaluated the suitability of BIA-measured FFMI as a simple surrogate marker of the ASMI and calculated the optimal FFMI cutoff value for low muscle mass screening to diagnose sarcopenia.DesignCross-sectional study.Setting and ParticipantsThis study included 1313 adults (women, 33.6%) aged 40-87 years (mean age, 55 ± 10 years) from the WASEDA’S Health Study.MethodsBody composition was measured using multifrequency BIA and DXA. Low muscle mass was defined according to the criteria of the Asian Working Group for Sarcopenia 2019.ResultsBIA-measured FFMI showed strong positive correlations with both BIA- (r = 0.96) and DXA-measured (r = 0.95) ASMIs. Similarly, in the subgroup analysis according to age and obesity, the FFMI was correlated with the ASMI. The areas under the receiver operating characteristic curve for screening low muscle mass defined by DXA-measured ASMI using BIA-measured FFMI values were 0.95 (95% CI 0.93-0.97) for men and 0.91 (95% CI 0.87-0.94) for women. The optimal BIA-measured FFMI cutoff values for screening low muscle mass defined by DXA-measured ASMI were 17.5 kg/m² (sensitivity 89%, specificity 88%) for men and 14.6 kg/m² (sensitivity 80%, specificity 86%) for women.Conclusions and ImplicationsThe FFMI showed a strong positive correlation with BIA- and DXA-measured ASMIs, regardless of age and obesity. The FFMI could be a useful simple surrogate marker of the ASMI for low muscle mass screening in sarcopenia in community settings. The suggested FFMI cutoff values for predicting low muscle mass are <18 kg/m² in men and <15 kg/m² in women.     

Development and Validation of Cutoff Value for Reduced Muscle Mass for GLIM Criteria in Patients with Gastrointestinal and Hepatobiliary–Pancreatic Cancers

The Global Leadership Initiative on Malnutrition (GLIM) criteria recommends using race- and sex-adjusted cutoff values for reduced muscle mass (RMM), but the only cutoff values available for Asians are the skeletal muscle mass index (SMI) established by the Asian Working Group for Sarcopenia (AWGS). This retrospective study aimed to develop and validate cutoff values for the fat-free mass index (FFMI) and arm circumference (AC) of Asians, and to investigate the association between GLIM malnutrition and prognosis. A total of 660 patients with primary gastrointestinal (GI) and hepatobiliary–pancreatic (HBP) cancers who underwent their first resection surgery were recruited and randomly divided into development and validation groups. The FFMI and AC cutoff values were calculated by receiver operating characteristic curve analysis for the AWGS SMI as the gold standard. The cutoff values for each RMM were used to diagnose malnutrition on the basis of GLIM criteria, and the survival rates were compared. The optimal FFMI cutoff values for RMM were 17 kg/m² for men and 15 kg/m² for women, and for AC were 27 cm for men and 25 cm for women. In the validation group, the accuracy of the FFMI and AC cutoff values to discriminate RMM were 85.2% and 68.8%, respectively. Using any of the three measures of RMM, overall survival rates were significantly lower in the GLIM malnutrition group. In conclusion, the cutoff values for the FFMI and AC in this study could discriminate RMM, and GLIM malnutrition using these cutoff values was associated with decreased survival.     

Fat-free mass depletion in cystic fibrosis: Associated with lung disease severity but poorly detected by body mass index

ObjectiveMalnutrition in cystic fibrosis (CF) is associated with poorer survival, but the determinants of fat-free mass (FFM) depletion are not well-characterized. It is unknown whether routine nutritional indicators, including body mass index (BMI), are adequate for detecting FFM depletion. This study aimed to determine the prevalence of FFM depletion in adults with CF, to compare fat-free mass index (FFMI) with BMI, and to identify predictors of FFM depletion.MethodsThis was a prospective cross-sectional study of 86 adults with CF (19–59 y old). Body composition was assessed using dual-energy X-ray absorptiometry to determine FFMI and BMI. FFMI percentiles and Z-scores were derived from a reference population of 156 healthy adults. FFM depletion was defined as an FFMI below the fifth percentile for age and gender and low BMI as <18.5 kg/m². Univariate and multivariate analyses identified predictors of FFMI and FFMI Z-score.ResultsMean FFMIs were 18.3 ± 1.9 kg/m² in men with CF and 15.8 ± 1.1 kg/m² in women with CF (P < 0.0005). FFM depletion was found in 14% of adults with CF, and low BMI was found in 18.6%. The sensitivity of BMI for detecting FFM depletion was 42%. Forced expiratory volume in 1 s as a percentage of predicted was independently associated with FFMI in women (r = 0.62, P < 0.0001) and men (r = 0.28, P = 0.045) and FFMI Z-score (r = 0.41, P < 0.0001).ConclusionFFM depletion was found in 14% of adults with CF, but was undetectable by BMI in 58% of these patients. These findings, together with the association of FFMI with forced expiratory volume in 1 s predicted, suggest a role for body composition assessment in adult CF care.     

Comparison of fat-free mass index and fat mass index in Chinese adults

Background/Objectives:To compare the characteristics of body composition for different gender and age in a large number of apparently healthy Chinese subjects, and to determine reference values for fat-free mass index (FFMI) and fat mass index (FMI).Subjects/Methods:In total, 61?382 Chinese adults (age range: 18-92 years) were consecutively enrolled into the study. Body composition was measured using bioelectrical impedance analysis with a tetrapolar impedance meter.Results:The skeletal muscle mass, fat-free mass (FFM), FFMI and body mass index (BMI) were significantly higher in men than in women (P<0.05), but FM% and FMI were significantly higher in women (P<0.05). In the group with normal BMI (BMI 18.5-23.9?kg/m(2), 18-92?years), the reference values (5th-95th percentile) of FM%, FFMI and FMI were 9.7-34.5%, 14.15-19.76 and 1.99-7.75?kg/m(2) in men, and 18.1-35.8%, 13.82-17.89 and 3.68-8.16?kg/m(2) in women, respectively.Conclusions:Reference intervals for FFMI and FMI could be of practical value for the clinical evaluation of a deficit in FFM with or without excess FM for a given age category, complementing the classical concept of BMI in a more qualitative manner, although these indices are only suggestive indications for the degree of obesity. In contrast to BMI, similar reference ranges of FFMI seem to be more utilizable with advancing age.     

Initial BMI and Weight Loss over Time Predict Mortality in Parkinson Disease

ObjectivesAlthough weight loss is a frequent symptom in Parkinson disease (PD), there have been few studies on the association between body mass index (BMI) and mortality. The objective of this study was to investigate the association between BMI and change in BMI at diagnosis in patients with PD and all-cause mortality.DesignCohort study using Korean National Health Insurance Service–Elderly Cohort data.Setting and ParticipantsPatients with new-onset PD were selected using the International Classification of Diseases 10th edition code (G20). Then, patients who were diagnosed more than 3 times with PD and had been prescribed anti-parkinsonian medication for ≥30 days were included. Those with a combined diagnosis of atypical parkinsonism and secondary parkinsonism were excluded.MethodsThe primary outcome was all-cause mortality. Anthropometric data, including height and weight, were obtained from the health screening data to calculate BMI. The Cox proportional hazards model was used to assess mortality risk by BMI.ResultsAmong the 2703 patients with PD, 492 (18.20%) died during the 11-year follow-up period. There was a significant inverse dose-response relationship between baseline BMI and mortality [<18.5 kg/m²: hazard ratio (HR), 1.872, 95% CI, 1.338–2.494; 23–25 kg/m²: HR, 0.695, 95% CI, 0.546–0.886; 25–30 kg/m²: HR, 0.644, 95% CI, 0.476–0.869; ≥30 kg/m²: HR, 0.396, 95% CI, 0.165–0.950]. Change in BMI of 10% revealed a significant association with mortality. Subgroup analyses by sex showed a significant inverse dose-response relationship between BMI and all-cause mortality only in women.Conclusions and ImplicationsWe demonstrated an inverse dose-response association between BMI at diagnosis and mortality in patients with PD, especially in women. Early detection of PD before weight loss progression and proper management might improve mortality. The small number of obese PD participants in our study should be considered when interpreting and generalizing results.     

Evaluation of Nutritional Status and Methods to Identify Nutritional Risk in Rheumatoid Arthritis and Spondyloarthritis

Patients with rheumatoid arthritis (RA) and spondyloarthritis (SpA) experience several nutritional challenges and are prone to develop malnutrition. This observational study aimed to perform a comprehensive nutritional assessment of outpatients diagnosed with RA and SpA, as well as to evaluate methods to identify nutritional risk. Nutritional status was investigated by anthropometric measures, body composition (DXA, dual energy X-ray absorptiometry), and handgrip strength (HGS). Nutritional risk was classified by Nutritional Risk Screening 2002 (NRS2002) and malnutrition was defined by the Global Leadership Initiative on Malnutrition (GLIM) criteria and fat-free mass index (FFMI; kg/m², <16.7 (M), <14.6 (F)). Out of 71 included patients, 46 (66%) were abdominally obese, 28 (39%) were obese in terms of body mass index (BMI), and 33 (52%) were obese in terms of the fat mass index (FMI; kg/m², ≥8.3 (M), ≥11.8 (F)). Malnutrition was identified according to FFMI in 12 (19%) patients, according to GLIM criteria in 5 (8%) patients, and on the basis of BMI (<18.5 kg/m²) in 1 (1%) patient. None were identified by NRS2002 to be at nutritional risk. Our study revealed high prevalence of abdominal obesity and low FFMI. Waist circumference was a good indicator of FMI. BMI, NRS2002, and HGS did not capture patients with malnutrition identified by DXA.     

Body Mass Index and Disability in Chinese Nonagenarians and Centenarians

ObjectivesTo examine the potential association between body mass index (BMI) and activities of daily living (ADLs) and instrumental activities of daily living (IADLs) disabilities in a population-based sample of Chinese nonagenarians and centenarians.MethodsThis study analyzed data obtained from a survey conducted in 870 elderly Chinese adults aged 90 years or older in Dujiangyan. The participants were divided into 4 groups according to the World Health Organization (WHO) Asia criteria of underweight, normal weight, overweight, and obesity in BMI (<18.5, 18.5–23.0, 23.0–25.0, ≥25.0 kg/m², respectively) and to BMI quartile (<16.8, 16.8–18.9, 18.9–21.1, ≥21.1 kg/m², respectively). The ADL and IADL disabilities were measured using the physical self-maintenance scale (PSMS) and IADL scale developed by Lawton and Brody, respectively.ResultsThe participants included in the current statistical analyses were 233 men and 505 women. The mean age was 93.5 ± 3.2 years (ranging from 90 to 108 years). Using the WHO Asia criteria, the prevalence of underweight and obesity were 43.9% and 6.6%, respectively. In long-lived women, the prevalence of ADL and IADL disabilities was significantly higher in either the underweight group (39.4% and 72.9%, respectively) or the obesity group (38.1% and 77.7%, respectively) compared with the normal weight group (31.4% and 60.8%, respectively). After adjusting for relevant covariates, the underweight group and obesity group showed significantly increased odds ratios (ORs) for either ADL (1.5 and 1.8, respectively) or IADL disability (1.9 and 1.4, respectively). Similar results were found when using the BMI quartile. However, in long-lived men, no significant difference was found with respect to the prevalence of ADL or IADL disability and adjusted ORs among the different BMI groups.ConclusionsAmong Chinese long-lived adults, the risk of ADL and IADL disability was higher for women with both extremely low and high BMIs, but this pattern was not found in men.     

Rheumatoid cachexia,central obesity and malnutrition in patients with low-active rheumatoid arthritis: feasibility of anthropometry,Mini Nutritional Assessment and body composition techniques

Background and aims  The concurrent decrease in fat free mass (FFM) and increase in fat mass (FM), including central obesity, in patients with rheumatoid arthritis (RA) may be related to increased cardiovascular morbidity as well as to functional decline. The objectives of this study were to evaluate body composition and nutritional status in patients with RA and the feasibility of bioelectrical impedance (BIA) to detect rheumatoid cachexia. Methods  Eighty RA outpatients (76% women), mean age 61 (range 22–80) years and with mean disease duration of 6 (range 1–52) years, were assessed by body mass index (BMI), waist circumference (WC), whole-body dual-energy X-ray absorptiometry (DXA), BIA and the Mini Nutritional Assessment (MNA). Results  Fat free mass index (FFMI; kg/m²) was low in 26% of the women and in 21% of the men. About every fifth patient displayed concomitant low FFMI and elevated fat mass index (FMI; kg/m²), i.e. rheumatoid cachexia. BMI and MNA were not able to detect this condition. Sixty-seven percent had increased WC. Reduced FFM was independently related to age (p = 0.022), disease duration (p = 0.027), ESR (p = 0.011) and function trendwise (p = 0.058). There was a good relative agreement between DXA and BIA (FM r ² = 0.94, FFM r ² = 0.92; both p < 0.001), but the limits of agreement were wide for each variable, i.e. for FM −3.3 to 7.8 kg; and for FFM −7.9 to 3.7 kg. Conclusion  Rheumatoid cachexia and central obesity were common in patients with RA. Neither BMI nor MNA could detect this properly. There was a good relative agreement between DXA and BIA, but the limits of agreement were wide, which may restrict the utility of BIA in clinical practice. This work has in part been presented at the Congress of American College of Rheumatology in San Francisco, October 2008.     

Ultrasonography Shows Age-related Changes and Related Factors in the Tongue and Suprahyoid Muscles

ObjectivesTo investigate age and other factors related to the deterioration of the muscles used for swallowing, including the tongue and suprahyoid muscles.DesignCross-sectional study.Setting and ParticipantsThis study included 146 participants: 47 younger adults (23 men and 24 women; age range 23-44 years) recruited from a dental hospital and 99 community-dwelling older adults (37 men and 62 women, age range 65-86 years).MethodsAge (<65 years or ≥65 years), body mass index (BMI), skeletal muscle mass index (SMI), and tooth loss (Eichner classification) were measured. The cross-sectional areas (CSAs) of the tongue, geniohyoid muscle, and anterior belly of the digastric muscle were measured using an ultrasonic diagnostic apparatus. The correlation between each muscle's CSA and strength was examined. Multiple regression analyses were performed separately for each sex using each muscle CSA as the dependent variable and age, BMI, SMI, and the Eichner classification as explanatory variables.ResultsOlder men had a significant positive correlation between tongue pressure and CSA (r = 0.35, P = .031). Jaw opening force was positively correlated with geniohyoid muscle CSA (r = 0.41, P = .001) in older women. In the multiple regression analysis, age, BMI, and SMI were significantly associated with tongue CSA in men. Age was significantly and inversely associated with suprahyoid muscle CSA in both men and women. No explanatory variables were significantly associated with geniohyoid muscle CSA except age.Conclusions and ImplicationsThe tongue increased in volume, and the suprahyoid muscles underwent atrophy with age. The study results suggest that interventions to prevent dysphagia associated with aging should be tailored toward specific muscles. Direct muscle training is required for the suprahyoid muscles, whereas the maintenance of tongue muscle mass and function, as well as training for the tongue, requires attention to ensure optimal nutritional status and whole-body skeletal muscle mass.     

Body-Mass Index and Mortality in Incident Dementia: A Cohort Study on 11,398 Patients From SveDem,the Swedish Dementia Registry

BackgroundBody mass index (BMI) is used worldwide as an indirect measure of nutritional status and has been shown to be associated with mortality. Controversy exists over the cut points associated with lowest mortality, particularly in older populations. In patients suffering from dementia, information on BMI and mortality could improve decisions about patient care.ObjectivesThe objective was to explore the association between BMI and mortality risk in an incident dementia cohort.DesignCohort study based on SveDem, the Swedish Quality Dementia Registry; 2008–2011.SettingSpecialist memory clinics, Sweden.ParticipantsA total of 11,398 patients with incident dementia with data on BMI (28,190 person-years at risk for death).Main outcome measuresHazard ratios and 95% confidence intervals for mortality associated with BMI were calculated, controlling for age, sex, dementia type, results from Mini-Mental State Examination, and number of medications. BMI categories and linear splines were used.ResultsHigher BMI was associated with decreased mortality risk, with all higher BMI categories showing reduced risk relative to patients with BMI of 18.5 to 22.9 kg/m², whereas underweight patients (BMI <18.5 kg/m²) displayed excess risk. When explored as splines, increasing BMI was associated with decreased mortality risk up to BMI of 30.0 kg/m². Each point increase in BMI resulted in an 11% mortality risk reduction in patients with BMI less than 22.0 kg/m², 5% reduction when BMI was 22.0 to 24.9 kg/m², and 3% risk reduction among overweight patients. Results were not significant in the obese weight range. Separate examination by sex revealed a reduction in mortality with increased BMI up to BMI 29.9 kg/m² for men and 24.9 kg/m² for women.ConclusionHigher BMI at the time of dementia diagnosis was associated with a reduction in mortality risk up to and including the overweight category for the whole cohort and for men, and up to the normal weight category for women.     

Association of Body Mass Index With All-Cause Mortality in Acutely Hospitalized Older Patients

ObjectivesThe aim was to examine the relationship between body mass index (BMI) and mortality in older hospitalized patients taking activities of daily living (ADLs) into account.DesignRetrospective cohort study.Setting and ParticipantsNationwide population-based study of all patients aged ≥65 years admitted to Danish geriatric medical departments during 2005 to 2014 and included in the National Danish Geriatric Database.MethodsPatients were followed until death, emigration, or study termination (December 31, 2015). Primary outcome was all-cause mortality. BMI and ADLs were routinely assessed on admission and linked at an individual level to the Danish national health registers. Kaplan-Meier analysis was used to estimate crude survival according to each BMI subcategory and Cox regression to examine the association with mortality adjusting for age, comorbidity, polypharmacy, ADLs, marital status, prior hospitalizations, and admission year.ResultsIn total, 74,589 patients (63% women) were included aged [mean (SD)] 82.5 (7.5) years with BMI [mean (SD)] of 23.9 (5.1) kg/m². During follow-up 51,188 died. Follow-up time was 191,972 person-years. Unadjusted and adjusted hazard ratio (HR) for overall, 30-day, and 1-year mortality decreased significantly with increasing BMI. In women, the highest adjusted HR (95% confidence interval) for overall mortality was seen for underweight patients (BMI <16) 1.83 (1.72–1.95) and the lowest for obesity grade II patients (BMI = 35.0–39.9) 0.66 (0.60–0.73) when using normal weight (BMI = 18.5–24.9) as reference. In men, the HR for BMI <16 and BMI = 35.0–39.9 were 1.98 (1.76–2.23) and 0.56 (0.49–0.65), respectively.Conclusions and ImplicationsIn hospitalized older patients, association between mortality and BMI did not show a U-shaped or J-shaped curve after adjustment of multiple confounders, including ADLs. Instead, mortality was highest in patients with low BMI and decreased with increasing BMI before leveling off in the obese range. Our study highlights the need for a debate and reassessment of what should be the ideal BMI in this vulnerable patient group.     

Influence of age and gender on fat mass,fat-free mass and skeletal muscle mass among Australian adults: The Australian diabetes,obesity and lifestyle study (AusDiab)

Background

Bioelectrical impedance (BIA) represents a simple, inexpensive and non-invasive method that is often used to assess fat-mass (FM) and fat-free mass (FFM) in large population-based cohorts.

Objective

The aim of this study was to describe the reference ranges and examine the influence of age and gender on FM, FFM and skeletal muscle mass (SMM) as well as height-adjusted estimates of FM [fat mass index (FMI)], FFM [fat-free mass index (FFMI)] and SMM [SMM index (SMI)] in a national, population-based cohort of Australian adults.

Design and Participants

The analytical sample included a total of 8,582 adults aged 25–91 years of Europid origin with complete data involved in the cross-sectional 1999–2000 Australian, Diabetes, Obesity and Lifestyle (AusDiab) Study.

Measurements

Bioelectrical impedance analysis was used to examine components of body composition. Demographic information was derived from a household interview.

Results

For both genders, FFM, SMM and SMI decreased linearly from the age of 25 years, with the exception that in men SMI was not related to age and FFM peaked at age 38 years before declining thereafter. The relative loss from peak values to ≥75 years in FFM (6–8%) and SMM (11–15%) was similar between men and women. For FM and FMI, there was a curvilinear relationship with age in both genders, but peak values were detected 6–7 years later in women with a similar relative loss thereafter. For FFMI there was no change with age in men and a modest increase in women.

Conclusion

In Australian adults there is heterogeneity in the age of onset, pattern and magnitude of changes in the different measures of muscle and fat mass derived from BIA, but overall the age-related losses were similar between men and women.     

Body Mass Index and Waist-to-Height Changes During Teen Years in Girls Are Influenced by Childhood Body Mass Index

PurposeThis study examined longitudinal changes in waist-to-height ratio and components of body mass index (BMI) among young and adolescent girls of black and white race/ethnicity.MethodsGirls were recruited at age 9 years through the National Heart, Lung, and Blood Institute Growth and Health Study (NGHS) and were followed annually over 10 years. Girls were grouped into low (<20^th percentile), middle, and high (>80^th percentile) BMI on the basis of race-specific BMI percentile rankings at age 9, and low, middle, and high waist-to-height ratio, on the basis of waist-to-height ratio at age 11. BMI was partitioned into fat mass index (FM) and fat-free mass index (FMI).ResultsGirls accrued fat mass at a greater rate than fat-free mass, and the ratio of fat mass to fat-free mass increased from ages 9 through 18. There was a significant increase in this ratio after age at peak height velocity. Participants with elevated BMI and waist-to-height ratios at age 18 tended to have been elevated at ages 9 and 11, respectively. There were strong correlations between BMI at age 9 with several outcomes at age 18: BMI (.76) and FMI (.72), weaker but significant with FFMI (.37), and ratio of fat mass to fat-free mass (.53). In addition, there was significant tracking of elevated BMI from ages 9 through 18.ConclusionsIn girls, higher BMI levels during childhood lead to greater waist-to-height ratios and greater than expected changes in BMI by age 18, with disproportionate increases in fat mass. These changes are especially evident in adolescent girls of black race/ethnicity and after the pubertal growth spurt.     

Effect of Secular Trend,Age, and Length of Follow-up on Optimum Body Mass Index From 1985 Through 2015 in a Large Austrian Cohort

BackgroundObesity and its health consequences will dominate health care systems in many countries during the next decades. However, the body mass index (BMI) optimum in relation to all-cause mortality is still a matter of debate.Material and MethodsData of the Vorarlberg Health Monitoring & Prevention Program (VHM&PP, 1985–2005) and data provided by the Main Association of Austrian Social Security Institutions (MAASSI, 2005–2015) were analyzed. Information was available on age, sex, smoking status, measured height and weight, and mortality. Generalized additive models were used to model mortality as a function of BMI, calendar time, age, and follow-up.ResultsIn MAASSI (N = 282,216, 46.0% men), men and women were on average 2.7 years older than in VHM&PP (N = 185,361, 46.1% men). Average BMI was slightly higher in men (26.1 vs 25.7 kg/m²) but not in women (24.6 vs 24.7 kg/m²). We found an interactive effect of age and follow-up on the BMI optimum. Over age 35 years in men and 55 years in women, the BMI optimum decreased with length of follow-up. While keeping covariates fixed, BMI optimum increased slightly between 1985 and 2015 in men and women, 24.9 (95% CI, 23.9–25.9) to 26.4 (95% CI, 25.3–27.3), and 22.4 (95% CI, 21.7–23.1) to 23.3 (95% CI, 22.6–24.5) kg/m², respectively.ConclusionAge and length of follow-up have a pronounced effect on the BMI associated with the lowest all-cause mortality. After controlling for age and length of follow-up, the BMI optimum increased slightly over 30 years in this large study sample.Key words: BMI, mortality, age, secular trend, length of follow-up     

Increased length of hospital stay in underweight and overweight patients at hospital admission: a controlled population study

BACKGROUND: Reduced lean tissue as well as high fat mass may be independent nutritional risk factors resulting in increased length of hospital stay (LOS). This controlled population study (1707 patients, 1707 volunteers) aimed to evaluate the association between LOS in Geneva and Berlin patients at hospital admission and high fat mass index (FMI, kg/m2) and low fat-free mass index (FFMI, kg/m2), and the respective value of body mass index (BMI) and of FFMI and FMI for nutritional assessment. METHODS: Patients (891 men, 816 women) were prospectively recruited at hospital admission and compared to gender-, age- and height-matched healthy volunteers. Fat-free mass and fat mass, determined at admission by 50 kHz-bioelectrical impedance analysis, were expressed as indices (FFMI and FMI-kg/m2) to normalize for height. Patients were classified in four groups: normal, low FFMI, high FMI, or low FFMI and high FMI. Logistic regressions were used to determine the association between body composition and LOS. RESULTS: Higher FMI and lower FFMI were found in patients at hospital admission than in sex- and age-matched healthy volunteers. Low FFMI, high FMI, and low FFMI/high FMI combined, adjusted for age, were all significantly associated with longer LOS (high FFMI: 1-5 days OR 2.4, CI 2.0-2.9; 6-10 days OR 2.3, CI 1.8-3.0; 11 days OR 2.8, CI 2.2-3.5); low FMI: 1-5 days OR 1.9, CI 1.6-2.2; 6-10 days OR 2.7, CI 2.0-3.5, 11 days OR 2.1, CI 1.7-2.7; low FFMI/high FMI: 1-5 days OR 7.8, CI 5.3-11.4; 6-10 days OR 13.6, CI 7.8-23.5, 11 days OR 11.8, CI 7.0-19.8). CONCLUSION: Increased LOS is associated with adiposity (high FMI) and low muscle mass (low FFMI). The current study shows that both depletion of lean tissue and excess of fat mass negatively affect the LOS. Finally, we found that excess fat mass reduces the sensitivity of BMI to detect nutritional depletion.     

Long chain polyunsaturated fatty acids in neonatal nutrition.

Objective: Total body potassium (TBK) concentration is linearly correlated with the size of the body cell mass (BCM). The aim of this study was to compare BCM in normal-weight and obese individuals.

Methods: 271 individuals (207 males, 64 females), 20 to 67 years of age, participated in this study. Subjects were separated by body mass index (BMI): BMI < 25 kg/m² (BMI-L) and BMI > 25 kg/m² (BMI-H). ⁴⁰K was assessed using a whole-body counter and BCM was calculated.

Results: BCM and TBK were significantly greater in men, with a trend to be greater in women in BMI-H compared to men in BMI-L. TBK/body weight was significantly lower, while TBK/height was significantly greater for men and women in BMI-H compared to men and women in BMI-L. Fat-free mass (FFM) was significantly greater for men in BMI-H, with no significant differences in FFM between the two groups of women.

Conclusions: The healthy obese subjects in the present study had a greater BCM than the non-obese subjects. These results indicate that it is important to assess BCM in obese individuals because it could influence the type of weight loss regimen that will be used in order to preserve BCM.     

Prevalence of sarcopenia in the French senior population

Introduction A muscle mass normalized for height² (MMI) or for body weight (SMI) below 2SD under the mean for a young population defines sarcopenia. This study aimed at setting the cutoffs and the prevalence of sarcopenia in the French elderly population. Another objective was to compare the results obtained with SMI and MMI.Methods: Muscle mass was assessed by bioelectrical impedance analysis in 782 healthy adults (<40 years) to determine skeletal mass index (SMI, muscle mass*100/weight) and muscle mass index (MMI, muscle mass/height²). Prevalence was estimated in 888 middle aged (40–59 years) and 218 seniors (60–78 years). All were healthy people.Results: For women mean-2SD were 6.2 kg/m² (MMI) and 26.6% (SMI); for men limits were 8.6 kg/m² (MMI) and 34.4% (SMI). In middle aged persons a small number of them were identified as sarcopenic. In healthy seniors, 2.8% of women and 3.6% of men were sarcopenic (MMI). The prevalence was 23.6% in women and 12.5% in men with SMI. MMI and SMI identified different sarcopenic populations, leaner subjects for MMI while fatter subjects for SMI.Conclusion: Cutoff values for the French population were defined. Prevalence of sarcopenia was different from that in the US population.     

Risk factors differ between recurrent and incident preeclampsia: a hospital-based cohort study

PurposeTo examine whether risk factors, including prepregnancy body mass index (BMI), differ between recurrent and incident preeclampsia.MethodsData included electronic medical records of nulliparas (n = 26,613) delivering 2 times or more in Utah (2002–2010). Modified Poisson regression models were used to examine (1) adjusted relative risks (RR) of preeclampsia and 95% confidence intervals (CI) associated with prepregnancy BMI; (2) maternal risk factor differences between incident and recurrent preeclampsia among primiparous women.ResultsIn the first pregnancy, compared with normal weight women (BMI: 18.5–24.9), preeclampsia risks for overweight (BMI: 25–29.9), obese class I (BMI: 30–34.9), and obese class II/III (BMI: ≥35) women were 1.82 (95% CI = 1.60–2.06), 2.10 (95% CI = 1.76–2.50), and 2.84 (95% CI = 2.32–3.47), respectively, whereas second pregnancy–incident preeclampsia risks were 1.66 (95% CI = 1.27–2.16), 2.31 (95% CI = 1.67–3.20), and 4.29 (95% CI = 3.16–5.82), respectively. Recurrent preeclampsia risks associated with BMI were highest among obese class I women (RR = 1.60; 95% CI = 1.06–2.42) without increasing in a dose-response manner. Nonwhite women had higher recurrence risk than white women (RR = 1.70; 95% CI = 1.16–2.50), whereas second pregnancy–incident preeclampsia risk did not differ by race.ConclusionPrepregnancy BMI appeared to have stronger associations with risk of incident preeclampsia either in the first or second pregnancy, than with recurrence risk. Nonwhite women had higher recurrence risk.