Body mass index and mortality among community-dwelling elderly of Southern Brazil

Prevalence of low calf circumference in hospitalized patients classified by raw or body mass index-adjusted values

BACKGROUND

Adiposity can influence the estimation of muscle mass using calf circumference (CC) and underestimate the frequency of low CC. An adjustment for CC using body mass index (BMI) was proposed to reduce this effect. We aimed to compare the low CC frequency in hospitalized patients when considering raw and BMI-adjusted values and explore data by sex, age, and race (white and non-white).

METHODS

Secondary analysis from two cohort studies conducted with adult hospitalized patients using BMI and CC data collected in the first 72 h after hospital admission. We classified low CC by two approaches: (1) raw CC; (2) BMI-adjusted CC for patients with BMI ≥ 25. Cutoff values for low CC were ≤34 cm (men) and ≤33 cm (women).

RESULTS

Among 1272 patients (54.1 ± 15.3 years old; 51.7% women; 82.1% White race), low CC frequency was 30.6% and low BMI-adjusted CC was 68.9%. For all elevated BMI categories, the low CC frequency was higher when considering BMI-adjusted values (P < 0.001). Low CC was more frequent (P < 0.001) in older adults (38.7% by raw; 79.1% by BMI-adjusted value) than in younger adults (27.6% by raw; 65.2% by BMI-adjusted value) and it was not associated with race. Low CC by raw values was more frequent in men than in women (35.0% versus 26.4%; P = 0.001), but did not differ between sexes when classified by BMI-adjusted values (70.7% versus 67.1%; P = 0.184).

CONCLUSION

Low CC BMI adjusted was 2.2 times more frequent in comparison with raw CC values, and it was identified in >60% of patients with BMI ≥ 25.

Association of nutritional status and comorbidity with long-term survival among community-dwelling older males

BACKGROUND

Estimates of survival in the older can be of benefit in various facets, particularly in medical and individual decision-making. We aim to validate the value of a combination of nutrition status evaluation and comorbidity assessment in predicting long-term survival among community-dwelling older.

METHODS

The Charlson Comorbidity Index (CCI) was applied for comprehensive evaluation of comorbidities. Participants were classified into CCI score ≤ 2 and ≥ 3 subgroups. Nutritional status was assessed by using Mini Nutritional Assessment-Short Form (MNA-SF) and Geriatric Nutritional Risk Index (GNRI) evaluations. Mortality rates and survival curves over a 5-year period were compared among subgroups classified by CCI and/or MNA-SF/GNRI evaluations.

RESULTS

A total of 1033 elderly male participants were enrolled in this study, with an average age of 79.44 ± 8.61 years. 108 deceased participants (10.5%) were identified during a follow-up of 5 years. Cox proportional hazards regression analysis showed that age, CCI, MNA-SF and GNRI were independent predictors of 5-year all-cause death in this cohort. Compared to those with normal nutrition status and CCI ≤ 2, the subgroup at risk of malnutrition and CCI ≥ 3 had a significantly higher 5-year all-cause mortality rate (HR = 4.671; 95% CI:2.613-8.351 for MNA-SF and HR = 7.268; 95% CI:3.401-15.530 for GNRI; P < 0.001 for both). Receiver operating characteristic curve analysis demonstrated that a combination of either MNA-SF or GNRI with CCI had significantly better performance than CCI, MNA-SF or GNRI alone in predicting all-cause death.

CONCLUSION

The combination of nutritional assessment (MNA-SF or GNRI) with CCI can significantly improve the predictive accuracy of long-term mortality outcomes among community-dwelling older males.

Association of waist-calf circumference ratio, waist circumference, calf circumference, and body mass index with all-cause and cause-specific mortality in older adults: a cohort study

BACKGROUND

Waist circumference (WC), calf circumference (CC), and body mass index (BMI) have been independently linked to mortality. However, it's not yet clear how the waist-calf circumference ratio (WCR) relates to mortality. This study aims to investigate the relationship between WCR, WC, CC, and BMI with all-cause and cause-specific mortality in older adults.

METHODS

In the 2014 Chinese Longitudinal Healthy Longevity Survey, 4627 participants aged 65 years and older were included, and they were subsequently followed up in 2018. Cox proportional hazards models were utilized to estimate hazard ratios (HRs) and 95% confidence intervals (CIs) for all-cause and cause-specific mortality, based on WCR, WC, CC, and BMI.

RESULTS

During a median follow-up of 3.4 years, 1671 deaths (36.1%) occurred. Compared to the second quartile of WCR, the highest quartile had a higher risk of mortality from all causes (HR 1.42, 95%CI 1.24-1.64), cardiovascular disease (CVD) (HR 1.88, 95%CI 1.38-2.56), and other causes (HR 1.37, 95%CI 1.15-1.63). The first and fourth quartiles of WC had HRs of 2.19 (1.00-4.79) and 2.69 (1.23-5.89), respectively, for cancer mortality. The highest quartile of CC was associated with a lower risk of all-cause and other-cause mortality, whereas the lowest quartile was associated with a higher risk of all-cause, CVD, and other-cause mortality compared to the second CC quartile. Additionally, the lowest quartile of BMI was associated with a higher risk of all-cause and respiratory disease mortality. Interaction analyses showed that the effects of CC on all-cause and CVD mortality were more pronounced in adults aged ≥ 80 years (P-interaction < .05).

CONCLUSIONS

Higher WCR and lower CC increased the risk of all-cause, CVD, and other-cause mortality. Lower BMI was associated with higher all-cause and respiratory disease mortality risk, while WC only predicted cancer mortality.

Low calf circumference adjusted for body mass index is associated with prolonged hospital stay

BACKGROUND

Calf circumference (CC) is of emerging importance because of its practicality, high correlation with skeletal muscle, and potential predictive value for adverse outcomes. However, the accuracy of CC is influenced by adiposity. CC adjusted for BMI (BMI-adjusted CC) has been proposed to counteract this problem. However, its accuracy to predict outcomes is unknown.

OBJECTIVES

To evaluate the predictive validity of BMI-adjusted CC in hospital settings.

METHODS

A secondary analysis of a prospective cohort study in hospitalized adult patients was conducted. The CC was adjusted for BMI by reducing 3, 7, or 12 cm for BMI (in kg/m²) of 25-29.9, 30-39.9, and ≥40, respectively. Low CC was defined as ≤34 cm for males and ≤33 cm for females. Primary outcomes included length of hospital stay (LOS) and in-hospital death, and secondary outcomes were hospital readmissions and mortality within 6 mo after discharge.

RESULTS

We included 554 patients (55.2 ± 14.9 y, 52.9% men). Among them, 25.3% presented with low CC, whereas 60.6% had BMI-adjusted low CC. In-hospital death occurred in 13 patients (2.3%), and median LOS was 10.0 (5.0-18.0) d. Within 6 mo from discharge, 43 patients (8.2%) died, and 178 (34.0%) were readmitted to the hospital. BMI-adjusted low CC was an independent predictor of LOS ≥ 10 d (odds ratio = 1.70; 95% confidence interval: 1.18, 2.43], but it was not associated with the other outcomes.

CONCLUSIONS

BMI-adjusted low CC was identified in more than 60% of hospitalized patients and was an independent predictor of longer LOS.

Age is the most important factor for change in body mass index and waist circumference in older people in southern Brazil

OBJECTIVES

The aim of this study is to assess the changes in body mass index and waist circumference (WC) and their associations with sociodemographic, behavioral, and health characteristics in non-institutionalized older people in southern Brazil over a period of ≤6 y.

METHODS

This is a prospective study, with interviews conducted in 2014 and in 2019 to 2020. Of the 1451 individuals from Pelotas, Brazil, aged >60 y and interviewed in 2014, 537 were reevaluated in 2019 to 2020. An increase or decrease was defined as a variation of ≥5% in body mass index and WC in the second visit compared with the first. The association with changes in outcomes was assessed according to sociodemographic, behavioral, and health characteristics using multinomial logistic regression.

RESULTS

Approximately 29% of the older participants lost body mass. Regarding WC, there was an increase in 25.6% in the older participants. The older participants ages ≥80 y had greater odds of losing body mass (odds ratio [OR] = 4.73; 95% confidence interval [CI], 2.29-9.76) and of reducing WC (OR = 2.84; 95% CI, 1.59-6.94). Former smokers had, on average, 41% and 64% lower odds of losing and gaining body mass (95% CI, 0.37-0.95 and 95% CI, 0.19-0.68, respectively), and those who were on ≥5 medications had greater odds of gaining body mass (OR = 1.92; 95% CI, 1.12-3.28) and WC (OR = 1.79; 95% CI, 1.18-2.74).

CONCLUSIONS

Despite the high proportion of older people who kept their body mass index and WC stable during this period, many of them lost body mass and gained WC. The findings also highlighted the importance of age in the nutritional changes observed in the population.

The association between low calf circumference and mortality: a systematic review and meta-analysis

PURPOSE

Low calf circumference is an important indicator of malnutrition and has been widely studied, especially among older adults. However, data on the association between low calf circumference and mortality have been inconsistent. This systematic review was aimed to quantify this association.

METHODS

The internet databases (PubMed, Embase, ScienceDirect and Cochrane Library databases) were systematically searched from inception to November 01, 2021 for studies investigating the association between low calf circumference and mortality. A random effects model was adopted to pool the relevant data.

RESULTS

Low calf circumference was associated with a higher risk of mortality than normal calf circumference, with a pooled HR of 2.42 (95% CI 1.97-2.97, I² = 74.3%). In addition, this association between low calf circumference and morality was still statistically significant in the subgroup analysis across different settings, including hospitals (pooled HR = 2.63, 95% CI 1.93-3.58), nursing homes (pooled HR = 2.49, 95% CI 1.76-3.54), and communities (pooled HR = 2.22, 95% CI 1.60-3.07). Other subgroup analyses based on different cutoffs of calf circumference showed that, compared to individual with normal calf circumference, participants with low calf circumference had an increased risk of mortality (pooled HR = 2.66, 95% CI 2.06-3.43) when using the Asian Working Group for Sarcopenia (AWGS) criterion (≤ 34 cm for males and ≤ 33 cm for females). Similar results were found when the Mini Nutritional Assessment (MNA) criterion (≤ 31 cm) was used, with a pooled HR of 2.11 (95% CI 1.59-2.81).

CONCLUSION

Calf circumference, which is simple and convenient to measure, could be used to stratify the high-risk group, as low calf circumference was significantly associated with mortality among patients. Interventions, including exercise and nutrition programs, could be conducted promptly once low calf circumference is detected.

Calf Circumference and All-Cause Mortality: A Systematic Review and Meta-Analysis Based on Trend Estimation Approaches

OBJECTIVES

To perform a systematic review and meta-analysis and quantify the associations of total mortality with calf circumference (CC) in adults 18 years and older via combining various analyses based on empirical dichotomic CC, continuous CC, and dose-response CC.

METHODS

We conducted a systematic search of relevant studies in PubMed, EMBASE, Cochrane Library, and Web of Science published through April 12, 2022. This systematic review includes longitudinal observational studies reporting the relationships of total mortality with CC. We calculated the pooled relative risk (RR) and 95% confidence interval (CI) of total mortality with CC per 1 cm for each study and combined the values using standard meta-analysis approaches. Newcastle-Ottawa scale (NOS), Grading of Recommendations, Assessment, Development and Evaluations approach (GRADE), and the Instrument for assessing the Credibility of Effect Modification Analyses (ICEMAN) were assessed for meta-analyses.

RESULTS

Our analysis included a total of 37 cohort studies involving 62,736 participants, across which moderate heterogeneity was observed (I2=75.7%, P<0.001), but no publication bias was found. Study quality scores ranged from 6 to 9 (mean 7.7), with only three studies awarded a score of 6 (fair quality). We observed an inverse trend between total death risk and CC per 1 cm increase (RR, 0.95, 95% CI, 0.94-0.96; P<0.001; GRADE quality=high). Only a very slight difference was found among residents of nursing homes (6.9% mortality risk reduction per one cm CC increase), community-dwellers (5.4%), and those living in hospitals (4.8%), respectively (P for meta-regression=0.617). Low credible subgroup difference was found based on the ICEMAN tool.

CONCLUSIONS

Calf circumference is a valid anthropometric measure for mortality risk prediction in a community, nursing home, or hospital.

Body Mass Index and Mortality in Chinese Older Adults -New Evidence from a Large Prospective Cohort in China

OBJECTIVES

To comprehensively evaluate the association between BMI and death risk in people aged 65 years and over in Shenzhen, China, and suggest the optimal range of body mass index (BMI) for the older adults.

DESIGN

A prospective cohort study.

SETTING

A population-based study of elderly adults in Shenzhen, China.

PARTICIPANTS

359044 Shenzhen Healthy Ageing Research participants aged 65 and over with 4682 deaths during a mean of 1.5 years of follow-up were included in this analysis.

MEASURES

Hazard ratio of all-cause and cause specific mortality risks associated with BMI categories. The association between BMI and all-cause and cause specific mortality were independently estimated by Cox regression model.

RESULTS

Regardless of gender, BMI of 24 -29.9 kg/m2 was a protective factor for death in all ages, while BMI above 30 kg/m2 was still a protective factor for older adults under 70 years old. Regardless of age, BMI at 24-25.9 kg/m2 was associated with lower mortality in men, while BMI at 26-27.9 kg/m2 was associated with lower mortality in women. For the older adults without chronic diseases, BMI at 24-25.9 kg/m2 was also significantly associated with lower mortality. In the analysis of BMI and cause of death, we also found that BMI of 24-25.9 kg/m2 was significantly associated with the lower mortality from cardiovascular disease, cancer, chronic respiratory disease and digestive system disease in China.

CONCLUSION

BMI in the range of 24-25.9 kg/m2 may be protective for mortality in Chinese older adults. Additional more large-scale, multicenter and long-term follow-up studies are needed to confirm these findings in different populations.

The fatter, the better in old age: the current understanding of a difficult relationship

PURPOSE OF REVIEW

Obesity has shown a protective effect on mortality in older adults, also known as the obesity paradox, but there are still controversies about this relationship.

RECENT FINDINGS

Recent studies have shown a J or U-shaped relationship between BMI and mortality, wherein an optimal range is described between 22 and 37 kg/m2 depending on the condition. Many mechanisms can explain this protective effect of higher BMI, fat/muscle mass storage, more aggressive treatment in obese individuals, loss of bone mineral content and selection bias. However, BMI must be used with caution due to its limitations to determine body composition and fat distribution.

SUMMARY

Although BMI is an easy tool to evaluate obesity, its protective effect may be present to certain extend, from normal range to class I obesity (BMI 30-34.9 kg/m2), but then it becomes detrimental. Skeletal muscle mass and muscle function associated with adipose tissue assessment can add valuable information in the risk stratification. Further studies should be performed prospectively, adjust BMI for cofounding variable and consider other elderly subpopulations. To promote healthy ageing, excessive fat mass should be avoided and maintenance or improvement of skeletal muscle mass and muscle function should be stimulated in older adults.

Double Burden of Malnutrition and Inequalities in the Nutritional Status of Adults: A Population-Based Study in Brazil, 2019

Objective: To describe the inequalities in the double burden of malnutrition (DBM) in the adult population.

Methods: Study carried out with data from the VIGITEL study, conducted in 2019 in all Brazilian capitals. Underweight and excess weight were evaluated on the basis of years of schooling and age. Multi-level analysis was performed including Human Development Index of each capital and individual-level variables. The inequality slope index was used to assess the magnitude of the inequalities found. All analyses considered the svy command owing to the complexity of the sampling process.

Results: 47.119 individuals were studied. Men with no education had 6 percentage points more underweight compared to those with higher education. Higher prevalence of excess weight was found among men with higher education and women with no education. In women, the difference was 18 percentage points between extreme categories. Elderly people with no education had 10 percentage points more excess weight than those with higher education.

Conclusions: The findings suggest the need for intersectoral actions that can cope with the social inequalities and help confronting with the DBM in Brazil.