A requiem for BMI in the clinical setting

Body mass index versus bioelectrical impedance analysis for classifying physical function impairment in a racially diverse cohort of midlife women: the Study of Women's Health Across the Nation (SWAN)

BACKGROUND

Body composition strongly influences physical function in older adults. Bioelectrical impedance analysis (BIA) differentiates fat mass from skeletal muscle mass, and may be more useful than body mass index (BMI) for classifying women on their likelihood of physical function impairment.

AIMS

This study tested whether BIA-derived estimates of percentage body fat (%BF) and height-normalized skeletal muscle mass (skeletal muscle mass index; SMI) enhance classification of physical function impairment relative to BMI.

METHOD

Black, White, Chinese, and Japanese midlife women (N = 1482) in the Study of Women's Health Across the Nation (SWAN) completed performance-based measures of physical function. BMI (kg/m²) was calculated. %BF and SMI were derived through BIA. Receiver-operating characteristic (ROC) curve analysis, conducted in the overall sample and stratified by racial group, evaluated optimal cutpoints of BMI, %BF, and SMI for classifying women on moderate-severe physical function impairment.

RESULTS

In the overall sample, a BMI cutpoint of ≥ 30.1 kg/m² correctly classified 71.1% of women on physical function impairment, and optimal cutpoints for %BF (≥ 43.4%) and SMI (≥ 8.1 kg/m²) correctly classified 69% and 62% of women, respectively. SMI did not meaningfully enhanced classification relative to BMI (change in area under the ROC curve = 0.002; net reclassification improvement = 0.021; integrated discrimination improvement = - 0.003). Optimal cutpoints for BMI, %BF, and SMI varied substantially across race. Among Black women, a %BF cutpoint of 43.9% performed somewhat better than BMI (change in area under the ROC curve = 0.017; sensitivity = 0.69, specificity = 0.64).

CONCLUSION

Some race-specific BMI and %BF cutpoints have moderate utility for identifying impaired physical function among midlife women.

Low Muscle Mass Is a Predictor of Malnutrition and Prolonged Hospital Stay in Patients With Acute Exacerbation of Chronic Obstructive Pulmonary Disease: A Longitudinal Study

BACKGROUND

Malnutrition in chronic obstructive pulmonary disease (COPD) patients is more prevalent during times of exacerbation. Fat-free mass index (FFMI), calf circumference (CC), and adductor muscle pollicis thickness (AMPT) can be used to identify reduced muscle mass and have been found to be good predictors of clinical outcomes in other conditions, but they have not been investigated in COPD. Therefore, this study evaluated low muscle mass as predictor of malnutrition, prolonged length of stay (LOS), and in-hospital death in COPD patients.

METHODS

This prospective cohort study was carried out in hospitalized patients with COPD exacerbation. Malnutrition diagnosis was performed by Subjective Global Assessment, and muscle mass was assessed by FFMI, calculated using fat-free mass from bioelectrical impedance, CC, and AMPT. Clinical outcomes (LOS and in-hospital death) were collected from records.

RESULTS

One hundred seventy-six patients were included (68.2 ± 10.4 years old, 56.2% women); 74.2% were classified as Global Initiative of Chronic Obstructive Lung Disease 2 or 3 and 58.2% as malnourished. The median LOS was 11 (7-19) days, and the incidence of death was 9.1%. Low FFMI and CC predicted malnutrition (low CC: odds ratio [OR], 4.6; 95% CI, 2.2-9.7 and low FFMI: OR, 8.8; 95% CI, 3.7-20.8) and were associated with prolonged LOS (low CC: OR, 2.3; 95% CI, 1.1-4.6 and low FFMI: OR, 2.5; 95% CI, 1.3-4.8).

CONCLUSION

Simple, inexpensive, and noninvasive parameters of muscle mass-FFMI and CC-are good predictors of malnutrition and prolonged LOS in COPD patients experiencing exacerbation.

Nutrition in times of Covid-19, how to trust the deluge of scientific information

PURPOSE OF REVIEW

The Covid-19 pandemic has daunted the world with its enormous impact on healthcare, economic recession, and psychological distress. Nutrition is an integral part of every person life care, and should also be mandatorily integrated to patient care under the Covid-19 pandemic. It is crucial to understand how the Covid-19 does develop and which risk factors are associated with negative outcomes and death. Therefore, it is of utmost importance to have studies that respect the basic tenets of the scientific method in order to be trusted. The goal of this review is to discuss the deluge of scientific data and how it might influence clinical reasoning and practice.

RECENT FINDINGS

A large number of scientific manuscripts are daily published worldwide, and the Covid-19 makes no exception. Up to now, data on Covid-19 have come from countries initially affected by the disease and mostly pertain either epidemiological observations or opinion papers. Many of them do not fulfil the essential principles characterizing the adequate scientific method.

SUMMARY

It is crucial to be able to critical appraise the scientific literature, in order to provide adequate nutrition therapy to patients, and in particular, to Covid-19 infected individuals.

Assessment of transthyretin cut-off values for a better screening of malnutrition: Retrospective determination and prospective validation

The use of transthyretin (TTR, prealbumin) as a marker of malnutrition and the definition of associated cut-offs are a matter of debate. In order to clarify this issue, we performed a retrospective study and then a prospective validation one. In the first study, data from 23,617 consecutive patients from our University hospital were analysed. Using the 0.11 and 0.05 g/L cut-off values defined by the French Health Authority, only 3.13% and 0.49% appeared malnourished or severely malnourished indicating that these cut-off values are clearly inappropriate. In the prospective study, consecutive patients were stratified for normal (≥0.2 g/L) or low (<0.2 g/L) TTR, and normal (<15 mg/L) or high (≥15 mg/L) C-reactive protein, hence defining 4 groups (n = 50 to 57/group), and data were analysed according to nutritional status estimated from patient files. Receiver operating characteristic (ROC) curve of TTR level associated with malnutrition allowed setting cut-off values at 0.17 and 0.12 g/L for malnutrition and severe malnutrition respectively.

Impact of body size and body composition on bladder cancer outcomes: Risk stratification and opportunity for novel interventions

Body size is emerging as a novel and clinically-relevant patient factor in bladder cancer research. Historically, a patient's body mass index (BMI) has been used as a proxy for obesity but it shows inconsistent associations with risk of developing the disease as well as with most clinical outcomes. More specific body composition features can be derived for patients using a variety of methods. To date, skeletal muscle measurements derived from preoperative computed tomography scans have shown the most consistent associations with clinical outcomes. Importantly, skeletal muscle can potentially be modified through resistance training and/or nutritional interventions. Large scale studies that evaluate the prognostic impact of not only body composition features at baseline but also describe changes in body composition post-treatment are needed to move the field forward to ultimately improve clinical outcomes for bladder cancer patients.

Sarcopenia and myosteatosis at presentation adversely affect survival after esophagectomy for esophageal cancer

Background Esophageal cancer remains a disease with poor survival and many complications. Measuring muscle mass and quality can identify patients with diminished muscle mass (sarcopenia) and muscle fat infiltration (myosteatosis). We studied the impact of sarcopenia and myosteatosis in resectable esophageal cancer on overall survival and complications. Patients and methods 139 patients received a radical esophagectomy. Skeletal muscle area (SMA) and muscle attenuation (MA) in CT images at L3 level were recorded and groups with and without sarcopenia and myosteatosis were compared for overall survival (OS), perioperative mortality, conduit complications, pleuropulmonary complications, respiratory failure requiring mechanical ventilation and other significant complications. Results Prevalence of sarcopenia and myosteatosis at presentation was 16.5% and 51.8%, respectively. Both were associated with decreased OS. Median survival was 18.3 months (CI 5.4-31.1) vs 31.0 months (CI 7.4-54.6) for sarcopenia/no sarcopenia (log rank p = 0.042) and 19.0 months (CI 13.3-24.7) vs 57.1 months (CI 15.2-99.0) for myosteatosis (log rank p = 0.044), respectively. A relationship between sarcopenia and myosteatosis and other negative outcomes after esophagectomy could not be established. Conclusions Sarcopenia and myosteatosis before esophagectomy are associated with decreased overall survival but not with more frequent perioperative complications. Identification of patients at risk can guide therapeutic decisions and interventions aimed at replenishing muscle reserves.

BMI and inverted BMI as predictors of fat mass in young people: a comparison across the ages

Background: The use of body mass index (BMI) could lead to over/under estimation of fat mass percentage (FM%). An alternative index (inverted BMI, iBMI) has been proposed as a better estimator of FM% in adults, while its practical feasibility in children and adolescents has not been fully investigated.Aim: To examine if iBMI can better estimate FM% than BMI in children/adolescents.Subjects and methods: Height, weight, and triceps and subscapularis skinfolds were measured in 6686 schoolchildren aged 11-14-years-old. BMI and iBMI (squared height/weight) were calculated; FM% was estimated by skinfold thicknesses. The Pearson correlation coefficient and the coefficient of determination were obtained to test the best regression model between the indexes and FM%.Results: FM% was linearly related to both indexes with R2 values that were overall > 0.7. No significant differences among the R2 values were found (p value = .2, ANOVA).Conclusion: BMI persists as a robust index for health surveillance screening in children/adolescents, being very intuitive and ready-to-use. Inverted BMI may be more accurate within a cohort of adults who experience only ponderal modifications, directly implicated in the variation of FM. In conclusion, the BMI remains a quick, handy and intuitive predictor of FM%.

Nutritional therapy and outcomes in underweight critically ill patients

BACKGROUND & AIMS

Critically ill patients with body mass index (BMI) < 20 kg/m² have worse outcomes than normal/overweight patients possibly because underweight is a marker of malnutrition. To assess the effects of nutrition therapy in this population during the first week of an ICU stay.

METHODS

Prospective, 2-centre, observational study. Nutritional evaluations were performed between days 2 and 3 (first) and between days 5 and 7 (second) of ICU admission. In the first evaluation, patients were divided into non-fed (without nutritional support) and early-fed (those already receiving nutritional support) groups. In the second evaluation, patients were divided according to caloric intake (≥or<20 kcal/kg) and protein intake (≥or<1.3 g of protein/kg).

RESULTS

Of the 4236 patients screened and 342 were included in the cohort. Mortality was 58.5% (median 21 [11-38.25] days of follow-up). Unadjusted patient survival was worse in the non-fed group than in the early-fed group (HR 1.66; 95%CI, 1.18 to 2.32). There was no difference in mortality between groups after adjusting for the SOFA score on the day of the evaluation. At the second evaluation, unadjusted analysis showed better in-hospital survival in patients with higher caloric (HR0.58; 95%CI, 0.40 to 0.86) and protein intake (HR0.59; 95%CI, 0.42 to 0.82); there was no association between mortality and caloric or protein intake after adjusting for the SOFA score on the day of the evaluation.

CONCLUSION

Nutritional therapy in the first week of ICU stay did not affect vital outcome after adjusting for the SOFA score on the day of the evaluation in underweight critically ill patients.

CLINICAL TRIAL REGISTRY

ClinicalTrials.gov number NCT03398343.

Correlations between the Quality of Life Domains and Clinical Variables in Sarcopenic Osteoporotic Postmenopausal Women

(1) Background: both sarcopenia and osteoporosis are major health problems in postmenopausal women. The aim of the study was to evaluate the quality of life (QoL) and the associated factors for sarcopenia in osteoporotic postmenopausal women, diagnosed according to EWGSOP2 criteria. (2) Methods: the study sample comprised 122 osteoporotic postmenopausal women with low hand grip strength and was divided into two groups: group 1 (probable sarcopenia) and group 2 (sarcopenia). QoL was assessed using the validated Romanian version of SarQol questionnaire. (3) Results: the D1, D4, D5, D7 and total SarQoL scores were significantly lower in women from group 2 compared to group 1. In group 2, women older than 70 years had significant lower values for D1, D3, D4, D6 and total SarQoL scores. Age, history of falls and the presence of confirmed and severe sarcopenia were predictors for overall QoL. (4) Conclusions: the frequency of sarcopenia was relatively high in our sample, with body mass index and history of falls as predictors for sarcopenia. Older osteoporotic postmenopausal women, with previous falls and an established sarcopenia diagnosis (low muscle strength and low muscle mass), were more likely to have a decreased quality of life.

Automated body composition analysis of clinically acquired computed tomography scans using neural networks

BACKGROUND & AIMS

The quantity and quality of skeletal muscle and adipose tissue is an important prognostic factor for clinical outcomes across several illnesses. Clinically acquired computed tomography (CT) scans are commonly used for quantification of body composition, but manual analysis is laborious and costly. The primary aim of this study was to develop an automated body composition analysis framework using CT scans.

METHODS

CT scans of the 3rd lumbar vertebrae from critically ill, liver cirrhosis, pancreatic cancer, and clear cell renal cell carcinoma patients, as well as renal and liver donors, were manually analyzed for body composition. Ninety percent of scans were used for developing and validating a neural network for the automated segmentation of skeletal muscle and adipose tissues. Network accuracy was evaluated with the remaining 10 percent of scans using the Dice similarity coefficient (DSC), which quantifies the overlap (0 = no overlap, 1 = perfect overlap) between human and automated segmentations.

RESULTS

Of the 893 patients, 44% were female, with a mean (±SD) age and body mass index of 52.7 (±15.8) years old and 28.0 (±6.1) kg/m², respectively. In the testing cohort (n = 89), DSC scores indicated excellent agreement between human and network-predicted segmentations for skeletal muscle (0.983 ± 0.013), and intermuscular (0.900 ± 0.034), visceral (0.979 ± 0.019), and subcutaneous (0.986 ± 0.016) adipose tissue. Network segmentation took ~350 milliseconds/scan using modern computing hardware.

CONCLUSIONS

Our network displayed excellent ability to analyze diverse body composition phenotypes and clinical cohorts, which will create feasible opportunities to advance our capacity to predict health outcomes in clinical populations.

Open Abdomen in Obese Patients: Pay Attention! New Evidences from IROA, the International Register of Open Abdomen

BACKGROUND

Open abdomen is the cornerstone of damage control strategies in acute care and trauma surgery. The role of BMI has not been well investigated. The aim of the study was to assess the role of BMI in determining outcomes after open abdomen.

METHODS

This is an analysis of patients recorded into the International Register of Open Abdomen; patients were classified in two groups according to BMI using a cutoff of 30 kg/m2. The primary outcome was in-hospital mortality; secondary outcomes were primary fascia closure rate, length of treatment, complication rate, entero-atmospheric fistula rate and length of ICU stay.

RESULTS

A total of 591 patients were enrolled from 57 centers, and obese patients were 127 (21.5%). There was no difference in mortality between the two groups; complications developed during the open treatment were higher in obese patients (63.8% vs. 53.4%, p = 0.038) while post-closure complications rate was similar. Obese patients had a significantly longer duration of the open treatment (9.1 ± 11.5 days vs. 6.3 ± 7.5 days; p = 0,002) and lower primary fascia closure rate (75.5% vs. 89.5%; p < 0,001). No differences in fistula rate were found. There was a linear correlation between the duration of open abdomen and the BMI (Pearson's linear correlation coefficient = 0,201; p < 0,001).

CONCLUSIONS

Open abdomen in obese patients seems to be safe as in non-obese patients with similar mortality; however, in obese patients the length of open abdomen is significantly higher with higher complication rate, longer ICU length of stay and lower primary fascia closure rate.

TRIAL REGISTRATION NUMBER

ClinicalTrials.gov, Identifier: NCT02382770.

Prevalence of sarcopenic obesity in adults with end-stage knee osteoarthritis

OBJECTIVE

To identify the prevalence of sarcopenic obesity, a phenotype of low muscle mass and high adiposity, in adults with end-stage knee osteoarthritis (OA). Various diagnostic criteria, including assessment of muscle/fat mass, muscle strength and physical function, were used to identify patients with and without sarcopenic obesity, and to compare outcomes of pain, function and quality of life.

DESIGN

Cross-sectional clinical study including adults with a body mass index (BMI) ≥30 kg/m² and knee OA. Body composition was measured by dual-energy X-ray absorptiometry (DXA). Assessments included gait speed, handgrip strength, six minute walk test, and self-reported pain, physical function, and health-related quality of life using the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) and EuroQol Foundation (EQ-5D).

RESULTS

151 adults (59% female) aged 65.1 ± 7.9 years, mean BMI 37.1 ± 5.5 kg/m², were included. Prevalence of sarcopenic obesity using diagnostic cut-offs of appendicular skeletal muscle mass (ASM) relevant to height², weight and BMI varied from 1.3% (95% confidence interval (CI): 0.2-4.7%) to 14.6% (9.4-21.2%) and 27.2% (20.2-35%), respectively. A combined diagnostic approach including low ASM with either low strength or low function yielded a prevalence of 8.6% (4.7-14.3%). Sarcopenic obesity influenced walking speed, endurance, strength, and patient-reported difficulty with self-care activities, regardless of diagnostic approach.

CONCLUSION

Prevalence of sarcopenic obesity varied depending on diagnostic criteria. Given the impact of this condition and OA on physical function, we suggest a combined diagnostic approach be used to clarify expected prevalence and enable early clinical identification and management of sarcopenic obesity in patients with knee OA.

The prediction of colorectal cancer using anthropometric measures: A Swedish population-based cohort study with 22 years of follow-up

Background

Obesity is a risk factor for colorectal cancer (CRC).

Objective

The objective of this article is to investigate whether anthropometric measures reflecting visceral obesity are better predictors of CRC than body mass index (BMI).

Methods

Data were analysed from the Malmö Diet and Cancer study in Sweden, comprising 16,669 women and 10,805 men (median age 56.6 and 59.1 years) followed for a median 21.5 years. Diagnoses of CRC were identified using Swedish national registers. Cox regression was used to test the associations of BMI, waist circumference (WC), waist-hip ratio, waist-to-height ratio, waist-to-hip-to-height ratio, A Body Shape Index (ABSI) and percentage body fat with the development of CRC adjusted for age, alcohol consumption, smoking, education and physical activity in men and women.

Results

None of the measures were significantly associated with an increased risk for CRC in women. WC was the strongest predictor of colon cancer (CC) in men and the only measure that was independent of BMI. ABSI was the only measure significantly associated with the risk of rectal cancer in men.

Conclusions

Visceral obesity, best expressed as WC, is a risk factor for CC in men but a poor predictive marker for CRC in women.

Association of food cravings with weight gain, overweight, and obesity in patients after liver transplantation

OBJECTIVE

After liver transplantation (LTx), patients often gain weight and many become overweight or obese; however, the association between LTx and food craving (FC) is unknown. The aim of this study was to describe FC among patients after LTx and verify its association with weight gain and obesity.

METHODS

This was a cross-sectional study that assessed 301 patients who underwent LTx (55.1 ± 12.7 y of age; time since LTx 6.6 ± 4.4 y; 64.1% men). Pregnant or nursing women were excluded. Patients were interviewed once either in the outpatient clinic or by completing the online questionnaire, from August 2016 to February 2017.

RESULTS

The median weight variation after Ltx was 8 kg (ranging from -16 to +41 kg). At evaluation, 62.5% (n = 188) of the patients presented excessive weight and 22.3% (n = 67) presented with obesity. The average score on the Food Craving Questionnaire-State (FCQ-S) was 33.4 ± 9 and for the Food Craving Questionnaire-Trait (FCQ-T) the median score was 68 (39-163). The FCQ-T dimensions of lack of control, preoccupation, emotion, environmental triggers/stimuli, and guilt correlated positively with weight gain (P < 0.05). The desire dimension on the FCQ-S was significantly associated with overweight in post-LTx patients (P < 0.05) and the FCQ-T dimensions [negative reinforcement (P = 0.013), lack of control (P = 0.016), emotion (P = 0.009), environmental triggers/stimuli (P = 0.029), and guilt (P = 0.007)] were associated with obesity.

CONCLUSION

Lack of control, preoccupation, emotion, trigger, and guilt were positively correlated with weight gain. Desire was significantly associated with overweight. Negative reinforcement, lack of control, emotion, environmental triggers/stimuli, and guilt were associated with obesity.

Adipose Tissue Distribution and Cardiovascular Disease Risk Among Breast Cancer Survivors

PURPOSE

Cardiovascular disease (CVD) is a major source of morbidity and mortality among breast cancer survivors. Although body mass index (BMI) is associated with CVD risk, adipose tissue distribution may better identify patients with a high risk of CVD after breast cancer.

METHODS

Among 2,943 patients with nonmetastatic breast cancer without prior CVD, we used International Classification of Diseases (9th and 10th revisions) codes to identify incidence of nonfatal stroke, myocardial infarction, heart failure, or CVD death. From clinically acquired computed tomography scans obtained near diagnosis, we measured visceral adiposity (centimeters squared), subcutaneous adiposity (centimeters squared), and intramuscular adiposity (fatty infiltration into muscle [Hounsfield Units, scored inversely]). We estimated hazard ratios (HRs) and 95% CIs per SD increase in adiposity accounting for competing risks and adjusting for demographics, smoking, cancer treatment, and pre-existing CVD risk factors.

RESULTS

Mean (SD) age was 56 (12) years. Over a median follow-up of 6 years, 328 CVD events occurred. Each SD increase in visceral or intramuscular adiposity was associated with an increase in CVD risk (HR, 1.15 [95% CI, 1.03 to 1.29] and HR, 1.21 [95% CI, 1.06 to 1.37]), respectively). Excess visceral and intramuscular adiposity occurred across all BMI categories. Among normal-weight patients, each SD greater visceral adiposity increased CVD risk by 70% (HR, 1.70 [95% CI, 1.10 to 2.62]).

CONCLUSION

Visceral and intramuscular adiposity were associated with increased CVD incidence after breast cancer diagnosis, independent of pre-existing CVD risk factors and cancer treatments. The increased CVD incidence among normal-weight patients with greater visceral adiposity would go undetected with BMI alone. Measures of adipose tissue distribution may help identify high-risk patients and tailor CVD prevention strategies.

Adductor pollicis muscle and nutritional status in heart failure patients: Is there an association?

OBJECTIVES

Adductor pollicis muscle thickness (APMT) has been used as a simple index for muscle mass for the assessment of nutritional status among hospitalized patients to identify malnutrition. The aim of this study was to evaluate the association between APMT and nutritional status in clinical patients diagnosed with congestive heart failure (CHF).

METHODS

APMT was measured in 500 patients with CHF on the dominant side. Nutritional status was assessed means of by the Subjective Global Assessment (SGA). Functional classification was performed according to guidelines provided by the New York Heart Association (NYHA), which establishes four categories of CHF severity. Poisson regression was used to verify the association of APMT, malnutrition, and severity of CHF. P ≤ 0.05 was considered statistically significant.

RESULTS

The malnutrition prevalence varied from 1.5% in patients with functional class I CHF to 96.2% in patients classified as functional class IV (P ≤ 0.001). In both sexes, APMT values were significantly lower in patients who were malnourished (P< 0.001). The proportion of patients with CHF and malnutrition was higher among women than men (47.2 versus 37.4%, P = 0.027). Malnutrition was slightly more common among patients ≥60 y of age compared with other age groups (48.3%, P ≤ 0.001). APMT is a significant protective factor for malnutrition even after controlling for sex, age, body mass index, and CHF functional class.

CONCLUSIONS

Malnutrition is highly prevalent among patients with CHF and is associated with functional class. APMT may be used as a simple index for muscle mass for the assessment of nutritional status in these patient populations, and is also associated with malnutrition in these patients, even after controlling for other risk factors.

Body Fat Mass and Risk of Cerebrovascular Lesions: The PRESENT (Prevention of Stroke and Dementia) Project

Obesity is known to increase the risk of stroke. It is unclear whether high absolute fat mass (FM) increases the risk of stroke independently. We studied the correlation between FM and silent brain infarction/white matter change (SI/WMC) using brain computed tomography. We selected subjects from the local government health promotion project. We randomly selected a target population that had never been diagnosed with stroke or dementia. FM was measured by bioelectrical impedance analysis (BIA). We divided the subjects into three groups according to the FM (gender-specific tertiles [GTx]). Seven hundred and twenty-two subjects (321 men) between 50 and 75 years of age were recruited. The overall odds ratio (OR) of SI/WMC was 2.23 (95% confidence interval (CI), 1.34-3.71; p = 0.002) times higher in the 37th to 100th percentiles (GT3) than in the first to 32nd percentiles (GT1). When men and women were separated, the OR of GT3 was 1.35 (CI, 0.62-2.94; p = 0.45) in men and 3.2 (CI, 1.60-6.40; p = 0.001) in women. The findings were not found to be statistically significant after adjusting for the well-known stroke risk factors. When the subjects were divided into a high FM (HFMG, GT3) and low FM group (LFMG, GT1 + GT2), the HFMG showed an increased OR of SI/WMC in women. Similar results were seen after adjusted (overall: OR, 1.38; CI, 0.85-2.25, p = 0.198; men: OR, 0.93; CI, 0.422-2.051; p = 0.86; women: OR, 2.02; CI, 1.06-3.86; p = 0.03). The findings suggest that high FM may be an independent risk factor for ischemic stroke among adults free from stroke and dementia, especially in women.

The Importance of Body Composition in Explaining the Overweight Paradox in Cancer-Counterpoint

Despite a greater risk of cancer associated with higher BMI, overweight (BMI 25-<30 kg/m²) and class I obese (BMI 30-<35 kg/m²) patients often have a paradoxically lower risk of overall mortality after a cancer diagnosis, a phenomenon called the "obesity paradox." Only when patients exceed a BMI ≥35 kg/m² are elevations in mortality risk consistently noted. This paradox has been dismissed as the result of methodologic bias, which we will describe and debate here. However, even if such bias influences associations, there is growing evidence that body composition may in part explain the paradox. This phenomenon may more accurately be described as a BMI paradox. That is, BMI is a poor proxy for adiposity and does not distinguish muscle from adipose tissue, nor describe adipose tissue distribution. Low muscle mass is associated with higher risk of recurrence, overall and cancer-specific mortality, surgical complications, and treatment-related toxicities. Patients with who are overweight or obese have on average higher levels of muscle than their normal-weight counterparts. Also, there is some evidence that patients with moderate levels of subcutaneous adipose tissue may have lower mortality. More research utilizing body composition is needed to clarify the effects of adiposity on cancer mortality. Cancer Res; 78(8); 1906-12. ©2018 AACR.

Low Muscularity as Assessed by Abdominal Computed Tomography on Intensive Care Unit Admission Is Associated With Mortality in a Critically Ill Asian Population

BACKGROUND

Low muscularity (LM) is associated with high mortality in the Caucasian critically ill population. Muscularity can be accurately measured by the skeletal muscle index (SMI; cm² /m² ) generated by computed tomography (CT). This study aimed to establish the overall and sex-specific cutoff values that predict hospital mortality in an Asian critically ill population.

METHODS

This single-center, retrospective, observational study included patients aged ≥18 years with an abdominal CT conducted within 72 hours of admission to the intensive care unit. SMI generated from CT images at the level of the mid-third lumbar vertebra were extracted from the medical records. Area under the receiver operating characteristic curves (AUC) was generated to determine the SMI cutoff values for hospital mortality. Association between LM (defined by SMI cutoff value) and hospital mortality was further evaluated by multivariable logistic regression.

RESULTS

In a sample of 228 patients, the overall SMI cutoff value (cm² /m² ) for hospital mortality was 42.0 (AUC: 0.637; sensitivity: 66.7%, specificity: 56.8%), whereas it was 46.5 in males and 35.3 in females. More males than females had LM (51.4% vs 37.5%), and >40% of overweight/obese patients had LM. Patients with LM were older and had a longer duration of mechanical ventilation and hospitalization. After adjusting for known confounders, LM independently predicted hospital mortality in the overall sample (adjusted odds ratio: 2.42; 95% CI 1.16-5.03; P = 0.003) and in both sexes.

CONCLUSION

This study established a set of SMI cutoff values that predict hospital mortality. LM is independently associated with hospital mortality.

Plasma Transthyretin as A Biomarker of Sarcopenia in Elderly Subjects

Skeletal muscle (SM) mass, the chief component of the structural compartment belonging to lean body mass (LBM), undergoes sarcopenia with increasing age. Decreased SM in elderly persons is a naturally occurring process that may be accelerated by acute or chronic nutritional deficiencies and/or inflammatory disorders, declining processes associated with harmful complications. A recently published position paper by European experts has provided an overall survey on the definition and diagnosis of sarcopenia in elderly persons. The present review describes the additional contributory role played by the noninvasive transthyretin (TTR) micromethod. The body mass index (BMI) formula is currently used in clinical studies as a criterion of good health to detect, prevent, and follow up on the downward trend of muscle mass. The recent upsurge of sarcopenic obesity with its multiple subclasses has led to a confused stratification of SM and fat stores, prompting workers to eliminate BMI from screening programs. As a result, investigators are now focusing on indices of protein status that participate in SM growth, maturation, and catabolism that might serve to identify sarcopenia trajectories. Plasma TTR is clearly superior to all other hepatic biomarkers, showing the same evolutionary patterns as those displayed in health and disease by both visceral and structural LBM compartments. As a result, this TTR parameter maintains positive correlations with muscle mass downsizing in elderly persons. The liver synthesis of TTR is downregulated in protein-depleted states and suppressed in cytokine-induced inflammatory disorders. TTR integrates the centrally-mediated regulatory mechanisms governing the balance between protein accretion and protein breakdown, emerging as the ultimate indicator of LBM resources. This review proposes the adoption of a gray zone defined by cut-off values ranging from 200 mg/L to 100 mg/L between which TTR plasma values may fluctuate and predict either the best or the worst outcome. The best outcome occurs when appropriate dietary, medicinal and surgical decisions are undertaken, resuming TTR synthesis which manifests rising trends towards pre-stress levels. The worst occurs when all therapeutic means fail to succeed, leading inevitably to complete exhaustion of LBM and SM metabolic resources with an ensuing fatal outcome. Some patients may remain unresponsive in the middle of the gray area, combining steady clinical states with persistent stagnant TTR values. Using the serial measurement of plasma TTR values, these last patients should be treated with the most aggressive and appropriate therapeutic strategies to ensure the best outcome.

Classification of Hydration in Clinical Conditions: Indirect and Direct Approaches Using Bioimpedance

Although the need to assess hydration is well recognized, laboratory tests and clinical impressions are impractical and lack sensitivity, respectively, to be clinically meaningful. Different approaches use bioelectrical impedance measurements to overcome some of these limitations and aid in the classification of hydration status. One indirect approach utilizes single or multiple frequency bioimpedance in regression equations and theoretical models, respectively, with anthropometric measurements to predict fluid volumes (bioelectrical impedance spectroscopy-BIS) and estimate fluid overload based on the deviation of calculated to reference extracellular fluid volume. Alternatively, bioimpedance vector analysis (BIVA) uses direct phase-sensitive measurements of resistance and reactance, measured at 50 kHz, normalized for standing height, then plotted on a bivariate graph, resulting in a vector with length related to fluid content, and direction with phase angle that indexes hydration status. Comparison with healthy population norms enables BIVA to classify (normal, under-, and over-) and rank (change relative to pre-treatment) hydration independent of body weight. Each approach has wide-ranging uses in evaluation and management of clinical groups with over-hydration with an evolving emphasis on prognosis. This review discusses the advantages and limitations of BIS and BIVA for hydration assessment with comments on future applications.

Inflammatory profile in optimally treated patients with adult versus early-onset asthma

Introduction: The age of asthma onset is often implicated in clinical manifestation, diagnosis, and management of the disease. Aim: To define demographic, clinical and functional features and inflammatory characteristics in induced sputum in patients with adult-onset asthma. Methods: Optimally treated patients from asthma clinics of two tertiary hospitals were included in the study. Patients underwent assessment of demographic characteristics, severity and treatment regimes, pulmonary function tests, and skin prick tests, as well as measurement of blood eosinophils and sputum induction for the assessment of sputum inflammatory cells, IL-8 and IL-13 levels in the supernatant. Results: Of the 333 patients recruited, 234 (70.2%) had adult-onset asthma. Adult-onset asthmatics were older, had a higher BMI, a shorter disease duration, and were less often atopic, compared to patients with early onset asthma. Higher proportions of patients with severe asthma presented increased levels of FeNO and blood eosinophils, both in the early and the adult-onset patient groups. Finally, obese patients with early onset asthma were characterized by less atopy compared to non-obese patients in the same group. Conclusion: Adult-onset asthma was characterized by less sputum eosinophilia, a nonatopic profile and a higher BMI compared to early-onset asthma. The presence of blood eosinophilia and increased FeNO in patients with severe asthma was comparable in the two groups.

Predicting Menstrual Recovery in Adolescents With Anorexia Nervosa Using Body Fat Percent Estimated by Bioimpedance Analysis

OBJECTIVE

To identify the threshold of total body fat percentage (TBF%) required for the resumption of menses (ROM) in hospitalized female adolescents with anorexia nervosa (AN) using bioimpedance analysis (BIA).

METHODS

All female adolescents hospitalized with AN in our medical center were evaluated in a longitudinal prospective study during the years of 2012-2017. Anthropometric data, body fat measured by BIA, and hormonal determinants were collected periodically, in addition to routine medical and gynecological assessments.

RESULTS

Sixty-two participants presented with secondary amenorrhea, of which 20 remained with amenorrhea and 42 had ROM during hospitalization. At discharge, participants with ROM regained significantly more weight, and had higher mean body mass index (BMI), BMI standard deviation scores, and TBF% than those who remained with amenorrhea. Receiver operating characteristic analysis identified that a TBF% of 21.2% had the highest discriminative ability for ROM (sensitivity = 88%, specificity = 85%, positive predictive value = 93%). Compared with the anthropometric parameters, TBF% had the highest area under curve (AUC = .895), which significantly differed from that of BMI standard deviation scores (AUC = .643, p = .007) and body weight (AUC = .678, p = .03).

CONCLUSIONS

BIA is a safe and relatively simple method to assess the TBF% required for the return of balanced menstrual cycles in female adolescents with AN. The TBF% with the highest discriminative ability for menstrual resumption as assessed by BIA is 21.2%.

The relationship between computed tomography-derived body composition, systemic inflammatory response, and survival in patients undergoing surgery for colorectal cancer

INTRODUCTION

Colorectal cancer is the fourth leading cause of cancer mortality in developed countries. There is evidence supporting a disproportionate loss of skeletal muscle as an independent prognostic factor. The importance of the systemic inflammatory response as a unifying mechanism for specific loss of skeletal muscle mass in patients with cancer is increasingly recognized. The aim of the present study was to delineate the relationship between the systemic inflammatory response, skeletal muscle index (SMI), skeletal muscle density (SMD), and overall survival in patients with colorectal cancer.

MATERIALS AND METHODS

The study included 650 patients with primary operable colorectal cancer. Computed tomography scans were used to define the presence of visceral obesity, sarcopenia (low SMI), and myosteatosis (low SMD). Tumour and patient characteristics were recorded. Survival analysis was carried out using univariate and multivariate Cox regression.

RESULTS

A total of 650 patients (354 men and 296 women) were included. The majority of patients were over 65 years of age (64%) and overweight or obese (68%). On univariate survival analysis, age, ASA, TNM stage, modified Glasgow Prognostic Score (mGPS), body mass index, subcutaneous fat index, visceral obesity, SMI, and SMD were significantly associated with overall survival (all P < 0.05). A low SMI and SMD were significantly associated with an elevated mGPS (<0.05). On multivariate analysis, SMI (Martin) [hazard ratio (HR) 1.50, 95% confidence interval (CI) 1.04-2.18, P = 0.031], SMD (Xiao) (HR 1.42, 95% CI 0.98-2.05, P = 0.061), and mGPS (HR 1.44, 95% CI 1.15-1.79, P = 0.001) were independently associated with overall survival. SMD but not SMI was significantly associated with ASA (P < 0.001).

CONCLUSIONS

This study delineates the relationship between the loss of quantity and quality of skeletal muscle mass, the systemic inflammatory response, and survival in patients with operable colorectal cancer.

Association between hepatitis C virus infection and osteoporotic fracture risk among postmenopausal women: a cross-sectional investigation in Taiwan

PURPOSE

Early low bone mass is a risk factor for osteoporotic fractures associated with multiple factors, including menopause and chronic liver diseases. Hepatitis C virus (HCV) also plays a major role in chronic liver disease and has many extrahepatic consequences, such as decreased bone mineral density (BMD). This study aimed to examine the hypothesis that HCV seropositivity is independently associated with menopausal BMD loss.

METHODS

This community-based, cross-sectional study was based in two rural townships in Yunlin County, Taiwan. A total of 636 menopausal women aged 45-80 years who underwent annual health checks were included. Viral markers of HCV, dual-energy X-ray absorptiometry and fracture risk assessment tool (FRAX) scores were measured. Logistic regression analysis was performed to assess the association between various predictors and the presence of low BMD.

RESULTS

The participants (median age: 65 years) had a HCV seropositivity rate of 32.2%. BMD was significantly lower in the HCV-seropositive participants in different anatomic locations than in the seronegative individuals (lumbar spine: -1.5 vs -1.1; total hip: -0.9 vs -0.6; femoral neck: -1.2 vs -1.0; p<0.05). HCV-seropositive subjects had higher rates of major osteoporotic fractures (11.3%±7.6%vs 9.0±6.8%; p<0.001) and hip fractures (3.4%±4.7%vs 2.3±4.9%; p=0.006) and a higher risk of lower BMD (osteopenia and osteoporosis) based on a multivariable regression analysis (adjusted OR: 1.8; 95% CI 1.16 to 2.81; p=0.009).

CONCLUSIONS

HCV infection may be an independent risk factor for menopausal BMD loss and fractures predicted by FRAX.

The Effect of Age upon the Interrelationship of BMI and Inpatient Health Outcomes

OBJECTIVES

There is growing evidence that the relationship between body mass index (BMI - defined as weight in kilograms divided by height in metres squared) and patient outcomes is age-dependent; specifically, a raised BMI may have a protective effect in older adults. This has been demonstrated clearly in the community setting; less clear is the effect of age on this relationship in the inpatient setting.

DESIGN, SETTING, PARTICIPANTS AND MEASUREMENTS

Retrospective analysis of 22,903 electronic records for patients discharged from two large public hospitals in South Australia between January 2015 and September 2018 inclusively. Records were retained if the patient's height and weight had been recorded during the admission, BMI was between 10-99 kg/m2 and it was the patient's first admission during that time. Patients were grouped by BMI (<18.5 kg/m2 ("underweight"), 18.5-24.9 kg/m2 ("normal weight"), 25-29.9 kg/m2 ("overweight"), >30 kg/m2 ("obese")) and age (18-59 years, 60-79 years, > 80 years); for each group we measured the relative stay index (RSI) (actual length of stay divided by predicted length of stay), death in hospital and composite adverse outcome after discharge (unplanned readmission within 30 days and/or death within 30 days).

RESULTS

Underweight patients across all age groups generally experienced significantly poorer outcomes compared to those not underweight. In those aged 18-59 years there were no significant differences in outcomes between the normal weight, overweight and obese groups. In those aged 60-79 years overweight patients had a significantly reduced risk of RSI > 2 compared to those of normal weight (p=0.014), and both overweight and obese patients had a significantly reduced risk of adverse outcome after discharge when compared to those of normal weight (p=0.028 and p=0.009 respectively). In those aged 80 years or older, both overweight and obese patients had a significantly reduced risk of adverse outcome after discharge when compared to those of normal weight (p=0.028 and p=0.013 respectively), and obese patients had a significantly reduced risk of inpatient mortality and RSI >2 when compared to those of normal weight (p=0.027 and p=0.037 respectively).

CONCLUSION

A BMI > 25 kg/m2 in older patients is associated with reduced risk of prolonged admission, inpatient mortality and adverse outcomes following discharge. This adds to growing evidence that age-specific BMI guidelines are required for adults because the healthiest BMI in the older hospital patient is seemingly not in the range 18.5-24.9 kg/m2.

Longitudinal association of adiposity with wheezing and atopy at 22 years: the 1993 Birth Cohort, Pelotas, Brazil

Purpose

Asthma is a highly prevalent noncommunicable lung disease. The aim of this study was to evaluate the longitudinal association of obesity/adiposity with wheezing and atopy.

Methods

The population of the study was composed of participants from the 1993 Pelotas (Brazil) Birth Cohort. The following outcome variables were measured at 22 years: wheezing in the last 12 months, wheezing with atopy, wheezing without atopy, only atopy, and persistent wheezing at 18 and 22 years. Exposure variables were obesity body mass index, percent fat mass (FM), and fat mass index, which were obtained by precise methods (BOD POD and dual-energy X-ray absorptiometry [DXA]). Crude and adjusted logistic and multinomial logistic regressions were used in the analyses.

Results

The prevalence of wheezing (with and without atopy), wheezing without atopy, only atopy, and persistent wheezing were 10.6%, 3.9%, 30.9%, and 4.0%, respectively. To be obese or to belong to the highest tertile of obesity/adiposity at two follow-ups showed a cumulative and positive association with wheezing in the adjusted analysis; for atopy there was no significant association. The odds ratio (OR) for wheezing according to the percentage of total FM measured by DXA in the highest tertile at both follow-ups was 1.58 (95% CI: 1.14–2.20) against an OR of 1.16 (95% CI: 0.92–1.47) for atopy. Persistent wheezing was also associated with adiposity, but without statistical significance.

Conclusions

We found a positive longitudinal association between several measures of adiposity and wheezing at 22 years old. The effect was higher for cumulative adiposity; the results for atopy were not consistent.

Prevalence and Associated Factors of Sarcopenia in Nursing Home Residents: A Systematic Review and Meta-analysis

OBJECTIVE

To review the prevalence and associated factors of sarcopenia in nursing homes.

DESIGN

A systematic review and meta-analysis of published studies in MEDLINE, EMBASE, and Cochrane Central Register of Controlled Trials.

SETTING

Nursing homes.

PARTICIPANTS

Older adults aged ≥60 years.

MEASUREMENTS

Sarcopenia was defined according to various validated diagnostic criteria, such as the European Working Group on Sarcopenia in Older People (EWGSOP) criteria and skeletal muscle index (SMI). We performed meta-analyses with random effects models to calculate the pooled prevalence of sarcopenia. The risk of bias of the included studies was evaluated using a 10-item tool explicitly designed for prevalence studies.

RESULTS

We included 16 studies with a total of 3585 participants from 129 nursing homes. The included studies were of low to moderate risk of bias. The pooled prevalences of EWGSOP-defined sarcopenia and SMI-defined sarcopenia were 41% [95% confidence interval (CI) 32%-51%, 12 studies, 2685 cases] and 59% (95% CI 24%-93%, 3 studies, 643 cases), respectively. The pooled prevalences of EWGSOP-defined sarcopenia in women and men were 46% (8 studies, 1332 cases) and 43% (8 studies, 739 cases), respectively. The pooled data showed that malnutrition was an independent associated factor of EWGSOP-defined sarcopenia (odds ratio [OR] 1.74, 95% CI 1.36-2.24; 3 studies, 718 cases), but malnutrition risk (OR 1.01, 95% CI 0.53-1.94; 2 studies, 379 cases) and female gender were not (OR 1.14, 95% CI 0.11-11.66; 3 studies, 827 cases). The association between age and body mass index with sarcopenia was inconsistent across studies. Limited evidence indicated that smoking might be related to sarcopenia.

CONCLUSIONS/IMPLICATIONS

Sarcopenia is highly prevalent in older nursing home residents. Malnutrition may be an associated factor of sarcopenia. More prospective studies are needed to clarify the association between age, gender, malnutrition, and smoking with sarcopenia.

Exploring the role of physical activity and exercise for managing vascular comorbidities in people with multiple sclerosis: A scoping review

INTRODUCTION

Vascular comorbidities are prevalent among people with multiple sclerosis (MS) and have adverse disease-related consequences. In the general population, physical activity (PA) and exercise training have proven beneficial at all levels of vascular disease risk management. People with MS exhibit particularly low rates of PA; therefore, PA represents a modifiable health behavior for potentially managing vascular comorbidity risk in MS, and in turn, reducing disease burden. However, points of evidence justifying such an approach have yet to be summarized.

OBJECTIVE

To conduct a scoping review of existing evidence linking PA and exercise training to potential modification of vascular comorbidities and related risk factors in people with MS.

METHODS

We searched five electronic databases (PubMed, Ovid MEDLINE, Embase, PsycINFO, and CINAHL Plus) from inception to November 2017, for articles involving relevant vascular comorbidities (obesity, hyperlipidemia, heart disease, hypertension, and diabetes) in people with MS in conjunction with measures of PA, physical fitness, sedentary behavior, or exercise training. Studies were limited to English-language and primary research articles. Data were extracted and summarized by comorbidity type and study design (observational vs. interventional).

RESULTS

Our initial search identified 1028 articles; subsequent screening resulted in 34 articles meeting the final inclusion criteria, including both observational (n = 17) and interventional (n = 17) studies. Most of the articles reported on obesity (n = 29), although evidence surrounding hyperlipidemia (n = 5), arterial function and hypertension (n = 5), and diabetes (n = 5) was also identified. Data supporting a beneficial role for PA or exercise training could be drawn from each comorbidity category. Overall, 14 of the 17 observational studies identified (82.4%) reported an association between higher levels of PA or cardiorespiratory fitness, or decreased sedentary behavior, and better function of at least one risk factor related to vascular comorbid conditions in people with MS. The efficacy of exercise training in limiting vascular comorbidity risk and burden was dependent upon intervention type and duration, with 9 of 17 interventional studies (52.9%) reporting improvement in at least one relevant measure of vascular comorbidity in participants with MS.

CONCLUSIONS

Evidence points to a potential relationship between PA and exercise and risk factors related to vascular comorbidities in people with MS. PA and exercise training interventions may represent an effective therapeutic strategy for managing vascular comorbidities in people with MS, justifying further investigation.

Body composition-related functions: a problem-oriented approach to phenotyping

AIM

The objective of this study is to generate metabolic phenotypes based on structure-function relationships.

METHODS

In 459 healthy adults (54% females, 18 and 40 years old), we analyzed body composition by air-displacement densitometry (to assess fat mass, (FM) and fat-free mass (FFM)) and whole-body magnetic resonance imaging (to assess skeletal muscle mass (SMM) and masses of brain, heart, liver, kidneys, and subcutaneous (SAT) and visceral adipose tissue (VAT)), resting energy expenditure (REE) by indirect calorimetry, and plasma concentrations of insulin (Ins) and leptin (Lep).

RESULTS

Three "functional body composition-derived phenotypes" (FBCPs) were derived: (1) REE on FFM-FBCP, (2) Lep on FM-FBCP, and (3) Ins on VAT-FBCP. Assuming that being within the ± 5% range of the respective regression lines reflects a "normal" structure-function relationship, three "normal" FBCPs were generated with prevalences of 9.0%, 5.1%, and 6.8%, respectively, of the study population. The three "FBCPs" did not overlap and were independent from each other. When compared with the two other FBCPs, the "Lep on FM-FBCP" was leanest, whereas the "REE on FFM-FBCP" had the highest BMI and SAT. Taking into account FFM composition, a hierarchical multi-level model is proposed with brain at level 1, the liver at level 2, and SMM and FM at level 3 with insulin coordinating the interplay between level 1 and 2, whereas variance in plasma insulin levels impacts energy and substrate metabolism in SMM and AT.

CONCLUSION

Structure-function relationships can be used to generate FBCPs. Different FBCPs reflect different dimensions of normality (or health). This is evidence for the idea that there is no across the board "normal" state.

Nutrition, dietary intake, and eating behavior after liver transplantation

PURPOSE OF REVIEW

Nutritional status of patients after liver transplantation is affected by dietary intake and this, in turn, is affected by eating behavior. The present review will highlight recent studies on these topics after liver transplantation.

RECENT FINDINGS

Malnutrition drops significantly after liver transplantation. Recovery of weight lost during liver disease occurs within 1 year. Liver transplantation recipients gain weight up to the second or third year, often becoming overweight and obese. Muscle mass may not recover completely, and sarcopenia could increase within 1 year after liver transplantation. Some studies, but not all, demonstrated modifications of food intake before and after liver transplantation. A positive energy balance was found in the first year, and a greater energy intake along time after liver transplantation, although some authors mentioned potential underreporting of the true consumption, mainly among people overweight/obese. Dietary survey methods are unable to detect eating behavior, resulting in a lack of data. Weight gain and obesity were related to higher scores for patterns of eating behaviors after liver transplantation. Food deprivation in the pretransplantation period and psychological factors could affect eating behavior and consequently food intake and nutritional status of liver transplantation patients.

SUMMARY

Understanding eating behavior after liver transplantation could be key knowledge regarding dietary intake and its impact on nutritional modifications occurring after liver transplantation.

Stratified Probabilistic Bias Analysis for Body Mass Index-related Exposure Misclassification in Postmenopausal Women

BACKGROUND

There is widespread concern about the use of body mass index (BMI) to define obesity status in postmenopausal women because it may not accurately represent an individual's true obesity status. The objective of the present study is to examine and adjust for exposure misclassification bias from using an indirect measure of obesity (BMI) compared with a direct measure of obesity (percent body fat).

METHODS

We used data from postmenopausal non-Hispanic black and non-Hispanic white women in the Women's Health Initiative (n=126,459). Within the Women's Health Initiative, a sample of 11,018 women were invited to participate in a sub-study involving dual-energy x-ray absorptiometry scans. We examined indices of validity comparing BMI-defined obesity (≥30 kg/m), with obesity defined by percent body fat. We then used probabilistic bias analysis models stratified by age and race to explore the effect of exposure misclassification on the obesity-mortality relationship.

RESULTS

Validation analyses highlight that using a BMI cutpoint of 30 kg/m to define obesity in postmenopausal women is associated with poor validity. There were notable differences in sensitivity by age and race. Results from the stratified bias analysis demonstrated that failing to adjust for exposure misclassification bias results in attenuated estimates of the obesity-mortality relationship. For example, in non-Hispanic white women 50-59 years of age, the conventional risk difference was 0.017 (95% confidence interval = 0.01, 0.023) and the bias-adjusted risk difference was 0.035 (95% simulation interval = 0.028, 0.043).

CONCLUSIONS

These results demonstrate the importance of using quantitative bias analysis techniques to account for nondifferential exposure misclassification of BMI-defined obesity. See video abstract at, http://links.lww.com/EDE/B385.

The impact of sarcopenic obesity on knee and hip osteoarthritis: a scoping review

BACKGROUND

The progressive, debilitating nature of knee and hip osteoarthritis can result in severe, persistent pain and disability, potentially leading to a need for total joint arthroplasty (TJA) in end-stage osteoarthritis. TJA in adults with obesity is associated with increased surgical risk and prolonged recovery, yet classifying obesity only using body mass index (BMI) precludes distinction of obesity phenotypes and their impact on surgical risk and recovery. The sarcopenic obesity phenotype, characterized by high adiposity and low skeletal muscle mass, is associated with higher infection rates, poorer function, and slower recovery after surgery in other clinical populations, but not thoroughly investigated in osteoarthritis. The rising prevalence and impact of this phenotype demands further attention in osteoarthritis treatment models of care, particularly as osteoarthritis-related pain, disability, and current treatment practices may inadvertently be influencing its development.

METHODS

A scoping review was used to examine the extent of evidence of sarcopenic obesity in adults with hip or knee osteoarthritis. Medline, CINAHL, Web of Science and EMBASE were systematically searched from inception to December 2017 with keywords and subject headings related to obesity, sarcopenia and osteoarthritis.

RESULTS

Eleven studies met inclusion criteria, with indications that muscle weakness, low skeletal muscle mass or sarcopenia are present alongside obesity in this population, potentially impacting therapeutic outcomes, and TJA surgical risk and recovery.

CONCLUSIONS

Consideration of sarcopenic obesity should be included in osteoarthritis patient assessments.

Liver transplantation and alcoholic liver disease: History, controversies, and considerations

Alcohol consumption accounts for 3.8% of annual global mortality worldwide, and the majority of these deaths are due to alcoholic liver disease (ALD), mainly alcoholic cirrhosis. ALD is one of the most common indications for liver transplantation (LT). However, it remains a complicated topic on both medical and ethical grounds, as it is seen by many as a "self-inflicted disease". One of the strongest ethical arguments against LT for ALD is the probability of relapse. However, ALD remains a common indication for LT worldwide. For a patient to be placed on an LT waiting list, 6 mo of abstinence must have been achieved for most LT centers. However, this "6-mo rule" is an arbitrary threshold and has never been shown to affect survival, sobriety, or other outcomes. Recent studies have shown similar survival rates among individuals who undergo LT for ALD and those who undergo LT for other chronic causes of end-stage liver disease. There are specific factors that should be addressed when evaluating LT patients with ALD because these patients commonly have a high prevalence of multisystem alcohol-related changes. Risk factors for relapse include the presence of anxiety or depressive disorders, short pre-LT duration of sobriety, and lack of social support. Identification of risk factors and strengthening of the social support system may decrease relapse among these patients. Family counseling for LT candidates is highly encouraged to prevent alcohol consumption relapse. Relapse has been associated with unique histopathological changes, graft damage, graft loss, and even decreased survival in some studies. Research has demonstrated the importance of a multidisciplinary evaluation of LT candidates. Complete abstinence should be attempted to overcome addiction issues and to allow spontaneous liver recovery. Abstinence is the cornerstone of ALD therapy. Psychotherapies, including 12-step facilitation therapy, cognitive-behavioral therapy, and motivational enhancement therapy, help support abstinence. Nutritional therapy helps to reverse muscle wasting, weight loss, vitamin deficiencies, and trace element deficiencies associated with ALD. For muscular recovery, supervised physical activity has been shown to lead to a gain in muscle mass and improvement of functional activity. Early LT for acute alcoholic hepatitis has been the subject of recent clinical studies, with encouraging results in highly selected patients. The survival rates after LT for ALD are comparable to those of patients who underwent LT for other indications. Patients that undergo LT for ALD and survive over 5 years have a higher risk of cardiorespiratory disease, cerebrovascular events, and de novo malignancy.

Recent advances in understanding body weight homeostasis in humans

Presently, control of body weight is assumed to exist, but there is no consensus framework of body weight homeostasis. Three different models have been proposed, with a "set point" suggesting (i) a more or less tight and (ii) symmetric or asymmetric biological control of body weight resulting from feedback loops from peripheral organs and tissues (e.g. leptin secreted from adipose tissue) to a central control system within the hypothalamus. Alternatively, a "settling point" rather than a set point reflects metabolic adaptations to energy imbalance without any need for feedback control. Finally, the "dual intervention point" model combines both paradigms with two set points and a settling point between them. In humans, observational studies on large populations do not provide consistent evidence for a biological control of body weight, which, if it exists, may be overridden by the influences of the obesogenic environment and culture on personal behavior and experiences. To re-address the issue of body weight homeostasis, there is a need for targeted protocols based on sound concepts, e.g. lean rather than overweight subjects should be investigated before, during, and after weight loss and weight regain. In addition, improved methods and a multi-level-multi-systemic approach are needed to address the associations (i) between masses of individual body components and (ii) between masses and metabolic functions in the contexts of neurohumoral control and systemic effects. In the future, simplifications and the use of crude and non-biological phenotypes (i.e. body mass index and waist circumference) should be avoided. Since changes in body weight follow the mismatch between tightly controlled energy expenditure at loosely controlled energy intake, control (or even a set point) is more likely to be about energy expenditure rather than about body weight itself.

Does anthropometric and fitness parameters mediate the effect of exercise on the HRQoL of overweight and obese children/adolescents?

BACKGROUND

There is sufficient evidence about the effects of physical exercise programs on health-related quality of life (HRQoL) in obese and overweight children.

OBJECTIVES

The purpose of this study was to observe the effects on physical fitness and HRQoL in overweight and obesity children and their parents and find out whether the effect of intervention on anthropometric and physical fitness parameters mediated the improvements found in the proxies' perception of participant quality of life.

METHODS

151 overweight and obese children (106 intervention and 45 control) participated in a public exercise program. Anthropometrics characteristics, physical fitness, and HRQoL (EQ-5D-Y) were measured. Analysis of Covariance and effect size were performed to analyze the improvement. Mediation analyzed with bootstrap to observe whether anthropometric or physical fitness improvements mediate of the changes in the proxies' assessment of HRQoL.

RESULTS

Significant improvements were found in waist circumference, physical fitness, and HRQoL. The improvement of waist circumference showed a significant indirect effect on the change in the proxy perception of quality of life.

CONCLUSION

The reduction of waist circumference mediates the change on proxies' perception of quality of life and not by the improvement in physical fitness.

TRIAL REGISTRATION

ISRCTN97887613.

The Obesity Paradox in Cancer: How Important Is Muscle?

Although higher body mass index (BMI) increases the incidence of many cancers, BMI can also exhibit a null or U-shaped relationship with survival among patients with existing disease; this association of higher BMI with improved survival is termed the obesity paradox. This review discusses possible explanations for the obesity paradox, the prevalence and consequences of low muscle mass in cancer patients, and future research directions. It is unlikely that methodological biases, such as reverse causality or confounding, fully explain the obesity paradox. Rather, up to a point, higher BMI may truly be associated with longer survival in cancer patients. This is due, in part, to the limitations of BMI, which scales weight to height without delineating adipose tissue distribution or distinguishing between adipose and muscle tissue. Thus, cancer patients with higher BMIs often have higher levels of protective muscle. We assert that more precise measures of body composition are required to clarify the relationship of body size to cancer outcomes, inform clinical decision-making, and help tailor lifestyle interventions.

Association between pre-sarcopenia, sarcopenia, and bone mineral density in patients with chronic hepatitis C

BACKGROUND

Preserved skeletal muscle is essential for the maintenance of healthy bone. Loss of bone mineral density (BMD) and muscle strength, considered a predictor of BMD, have been demonstrated in patients with cirrhosis, but they are poorly studied in chronic hepatitis C (CHC) without cirrhosis. Thus, we aimed to evaluate the prevalence of low BMD and its association with body composition, muscle strength, and nutritional status in CHC.

METHODS

One hundred and four subjects [mean age, 50.5 ± 11.3 years; 75.0% males; 67.3% non-cirrhotic; and 32.7% with compensated cirrhosis] with CHC, prospectively, underwent scanning of the lean tissue, appendicular skeletal muscle mass (ASM), fat mass, lumbar spine, hip, femoral neck, and whole-body BMD by dual-energy X-ray absorptiometry. Muscle strength was assessed by dynamometry. Sarcopenia was defined by the presence of both low, ASM/height2 (ASMI) and low muscle strength according to the European Working Group on Sarcopenia in Older People criteria. The cut-off points for low ASMI and low muscle strength, for women and men, were < 5.45 and < 7.26 kg/m2 and < 20 and < 30 kg, respectively. According to the adopted World Health Organization criteria in men aged > 50 years, the T-score of osteopenia is between -1.0 and -2.49 standard deviation (SD) below the young average value and of osteoporosis is ≥-2.5 SD below the young normal mean for men, and the Z-score of low bone mass is ≤-2.0 SD below the expected range in men aged < 50 years and women in the menacme. Nutritional status evaluation was based on the Controlling Nutritional Status score.

RESULTS

Low BMD, low muscle strength, pre-sarcopenia, sarcopenia, and sarcopenic obesity were observed in 34.6% (36/104), 27.9% (29/104), 14.4% (15/104), 8.7% (9/104), and 3.8% (4/104) of the patients, respectively. ASMI was an independent predictor of BMD (P < 0.001). Sarcopenia was independently associated with bone mineral content (P = 0.02) and malnutrition (P = 0.01). In 88.9% of the sarcopenic patients and in all with sarcopenic obesity, BMI was normal. The mid-arm muscle circumference was positively correlated with ASMI (r = 0.88; P < 0.001).

CONCLUSIONS

This is the first study to demonstrate that ASM is an independent predictor of BMD in CHC. Mid-arm muscle circumference coupled with handgrip strength testing should be incorporated into routine clinical practice to detect low muscle mass, which may be underdiagnosed when only BMI is used. These findings may influence clinical decision-making and contribute to the development of effective strategies to screen the musculoskeletal abnormalities in CHC patients, independently of the stage of the liver disease.

Breastfeeding and complementary feeding associated with body composition in 18-19 years old adolescents in the 1993 Pelotas Birth Cohort

BACKGROUND

The first years of life are critical for human development, therefore it is important to investigate early factors that may influence the development of body composition later in life. In this study, we aimed to evaluate the association between breastfeeding duration and age of introduction of complementary feeding with body composition at 18-19 years.

METHODS

This is a prospective study conducted with adolescents belonging to the 1993 Pelotas Birth Cohort. Duration of breastfeeding, age of introduction of other types of milk and complementary feeding were obtained from a subsample of this cohort periodically monitored during the first year of life. The fat mass (FM) and fat-free mass (FFM) indices were estimated using plethysmography (BOD POD ™). Crude and adjusted analyses were stratified by sex using a linear regression model.

RESULTS

1438 adolescents (694 boys and 744 girls) had complete information on exposures and outcomes.. Among men, the mean FMI and FFMI were 4.0 ± 3.1 kg / m2 and 19.0 ± 1.9 kg / m2; and among women, 8.0 ± 3.2 kg / m2 and 15.5 ± 1.7 kg / m2, respectively. Neither breastfeeding duration nor age of introduction of complementary foods was associated with mean FMI in both sexes. Mean FFMI was higher among women who were breastfed for three months or more and among men who were breastfed for six months or more. Women who started the complementary feeding after five months of age had lower mean FFMI in adolescence.

CONCLUSION

The data suggest that only mean FFM in adolescence is associated with early feeding behaviors.

Physical activity and calorie intake mediate the relationship from depression to body fat mass among female Mexican health workers

Background

Depression is a foremost cause of morbidity throughout the world and the prevalence of depression in women is about twice as high as men. Additionally, overweight and obesity are major global health concerns. We explored the relationship between depression and body fat, and the role of physical activity and diet as mediators of this relationship in a sample of 456 adult female Mexican health workers.

Method

Longitudinal and cross-sectional analyses using data from adult women of the Health Workers Cohort Study (HWCS) Measures of body fat mass (kg from DEXA), dietary intake (kcal from FFQ), leisure time activity (METs/wk) and depression (CES-D) were determined in two waves (2004–2006 and 2010–2011). We explored the interrelation between body fat, diet, leisure time, physical activity, and depression using a cross-lagged effects model fitted to longitudinal data. We also fitted a structural equations model to cross-sectional data with body fat as the main outcome, and dietary intake and physical activity from leisure time as mediators between depression and body fat.

Results

Baseline depression was significantly related to higher depression, higher calorie intake, and lower leisure time physical activity at follow-up. From our cross-sectional model, each standard deviation increase in the depression score was associated with an average increase of 751 ± 259 g (± standard error) in body fat through the mediating effects of calorie intake and physical activity.

Conclusions

The results of this study show how depression may influence energy imbalance between calories consumed and calories expended, resulting in higher body fat among those with a greater depression score. Evaluating the role of mental conditions like depression in dietary and physical activity behaviors should be positioned as a key research goal for better designed and targeted public health interventions.

Trial registration

The HealthWorkers Cohort Study (HWCS) has been approved by the Institutional IRB. Number: 2005–785-012.

Electronic supplementary material

The online version of this article (10.1186/s12966-017-0612-x) contains supplementary material, which is available to authorized users.