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.

Is waist-calf circumference ratio associated with frailty in older adults? Findings from a cohort study.

BACKGROUND: The waist-calf circumference ratio (WCR) has been suggested as a potential indicator of visceral adiposity. Nevertheless, the relationship between WCR and the risk of frailty remains unclear. Therefore, our study aimed to investigate the association between WCR and longitudinal changes in WCR with frailty risk in older adults. METHODS: We included 2359 participants aged ≥ 65 years without frailty (frailty index [FI] ≤ 0.21) from the Chinese Longitudinal Healthy Longevity Survey in the 2014 wave. The follow-up was conducted in 2018. We investigated the relationship of WCR, waist circumference (WC), and calf circumference (CC) with frailty using both the Cox proportional hazards model and the generalized estimating equation (GEE). RESULTS: During a median follow-up of 4.0 years, 668 (28.2%) frailty occurred. Those with higher WCR and WC had a significantly increased risk of frailty (fifth quintile compared with first quintile: hazard ratio [HR] = 1.59, 95% confidence interval [CI] 1.24-2.04 for WCR; HR = 1.69, 95% CI 1.27-2.24 for WC), whereas those in the fourth quintile of CC had a lower likelihood of developing frailty compared to those in the first quintile (HR = 0.67, 95% CI 0.50-0.89). Interaction analyses showed that the effects of WCR on frailty were more pronounced in females (P-interaction = 0.016). GEE analyses revealed that increased WCR and WC were associated with a higher risk of frailty (odds ratio [OR] = 1.74, 95% CI 1.43-2.12 for WCR; OR = 1.03, 95% CI 1.02-1.04 for WC), while CC showed opposite results (OR = 0.95, 95% CI 0.93-0.97). CONCLUSIONS: A higher WCR and WC, as well as a lower CC, were significantly associated with higher frailty. Of these measures, WCR demonstrated the strongest association with frailty, suggesting that having a combination of high central fat and low lean body mass may increase the risk of developing frailty.

Association of waist-calf circumference ratio with incident cognitive impairment in older adults.

BACKGROUND: The longitudinal relation of central fat and muscle mass with cognitive function remains unclear. OBJECTIVES: We aimed to evaluate the relation of anthropometric measures, including BMI, waist circumference (WC), calf circumference (CC), and waist-calf circumference ratio (WCR), with incident cognitive impairment in older adults. METHODS: A total of 3312 participants aged ≥65 y (mean: 81.8 y) who were free of cognitive impairment [the Chinese version of the Mini-Mental State Examination (MMSE) scores ≥24 points] in the Chinese Longitudinal Healthy Longevity Survey were included. The primary outcome was incident cognitive impairment, defined as MMSE scores <24 points at the exit visit. Secondary outcomes were incident cognitive decline, defined as a reduction of MMSE scores ≥3 points at the exit visit, and incident decline in different cognitive domains, defined as a reduction of MMSE scores in the domain ≥15% at the exit visit. RESULTS: During a median follow-up duration of 3.6 y, 565 (17.1%) participants developed incident cognitive impairment. Overall, with mutual adjustments, higher WC [≥89 cm (fourth quartile) compared with <75 cm (first quartile); adjusted HR: 1.56; 95% CI: 1.19, 2.04] and higher WCR [≥2.9 (fourth quartile) compared with <2.4 (first quartile); adjusted HR: 1.96; 95% CI: 1.52, 2.52] were significantly associated with a higher risk of cognitive impairment, and higher CC [≥34 cm (fourth quartile) compared with <28 cm (first quartile); adjusted HR: 0.44; 95% CI: 0.33, 0.59] was associated with a lower hazard of cognitive impairment. Similar results were found for the secondary outcomes. However, BMI was not significantly associated with the study outcomes. CONCLUSIONS: High WC and low CC were significantly associated with higher incident cognitive impairment in older adults. Moreover, WCR had a relatively stronger association with cognitive impairment compared with each circumference, suggesting maintaining both higher lean mass and lower central fat in older adults for the prevention of cognitive impairment.

Central and Peripheral Adiposity Had Different Effect on Disability in Centenarians.

Purpose: To explore the correlations between waist circumference, body mass index, calf circumference (CC), and waist-calf circumference ratio (WCR) and activities of daily living (ADLs) and instrumental activities of daily living (IADLs) in Hainan centenarians. Patients and Methods: A total of 1,002 Hainan centenarians were selected by full sample household survey. ADLs and IADLs were used to investigate the ability of activity and instrumental activity in daily living. The possible non-linear associations were further analyzed using restricted cubic spline. Results: After adjusting for demographic characteristics (gender, age, ethnicity, marital status, educational level, and type of residence) and lifestyle (smoking, drinking, and exercise), the odds ratio (OR) of CC (continuous variable) on ADL disability in centenarians was 0.90 (95% CI: 0.85-0.96), while high WCR (continuous variable) was related with high risk of ADL disability (OR=1.73; 95% confidence interval[CI], 1.07-2.80). The ORs of CC and WCR for IADL severe disability were 0.86 (95% CI, 0.82-0.91) and 2.23 (95% CI, 1.52-3.28), respectively. Conclusion: Central (WCR) and peripheral (CC) adiposity had different effects on disability (ADL and IADL) in centenarians. Even in centenarians, maintaining muscle mass (with higher calf circumference) and avoiding central obesity are of positive significance for the prevention of ADL/IADL disability.

Waist-Calf Circumference Ratio Is an Independent Risk Factor of HRQoL in Centenarians.

PURPOSE: To analyze the associations between waist circumference (WC), body mass index (BMI), waist-hip ratio (WHR), waist-height ratio (WHtR), calf circumference, waist-calf circumference ratio (WCR), and quality of life in Hainan centenarians. PATIENTS AND METHODS: A total of 1002 centenarians in Hainan were selected by a full sample survey. The EQ-5D visual analogue scale (EQ-5D-VAS) was used to investigate the quality of life. Restricted cubic splines were used to analyze and visualize the linear relationships. RESULTS: After adjustment, the standard ß values for BMI, WC, WHR, WHtR, calf circumference, and WCR associated with EQ-5D score were 0.101, 0.126, -0.018, 0.100, 0.302, and -0.219, respectively; all associations except for WHR were significant (P < 0.01). With increasing BMI, WC, and calf circumference, the risk of EQ-5D score <1 decreased (odds ratios [ORs] 0.91 [95% confidence interval (CI): 0.86-0.97), 0.97 [95% CI: 0.95-0.99], and 0.87 [95% CI: 0.82-0.92] after adjustment, respectively). With increasing WCR, the risk also increased (OR 2.70 [95% CI: 1.54-4.75]). CONCLUSION: After excluding nutritional and muscle retention factors, fat central distribution negatively impacted the health-related quality of life of the oldest old population.