Body Composition in Late Midlife as a Predictor of Accelerated Age-associated Deficit-accumulation From Late Midlife into Old Age: A Longitudinal Birth Cohort Study

Abstract

Background Body mass index (BMI) may not be an optimal predictor of frailty as its constituents, lean and fat mass, may have opposite associations with frailty. Methods A linear mixed model analysis was performed in the Helsinki Birth Cohort Study (n=2000) spanning from 57 to 84 years. A 39-item frailty index (FI) was calculated on three occasions over 17 years. Body composition in late midlife included BMI, percent body fat (%BF), waist-to-hip ratio (WHR), lean mass index (LMI), and fat mass index (FMI). Results Mean FI levels increased by 0.28%/year among men and by 0.34%/year among women. Among women, per each kg/m 2 higher BMI and each unit higher %BF the increases in FI levels per year were 0.013 percentage points (PP) steeper (95% CI=0.004, 0.023) and 0.009 PP steeper (95% CI=0.002, 0.016) from late midlife into old age. Among men, per each 0.1-unit greater WHR the increase in FI levels was 0.074 PP steeper per year (95% CI=-0.0004, 0.148). Cross-sectionally, greater FMI and LMI in late midlife were associated with higher FI levels but the direction of the association regarding LMI changed after adjustment for FMI. The categories ‘high FMI & high LMI’ and ‘high FMI & low LMI’ showed the highest FI levels relative to the category ‘low FMI & low LMI’. Conclusions In late midlife, greater adiposity (%BF) among women and abdominal obesity (WHR) among men may predispose to higher levels of frailty from late midlife into old age. Greater lean mass alone may be protective of frailty, but not in the presence of high fat mass.

The Influence of Obesity on Bone Health in Post-COVID-19 Recovery- Single-Center Experience

“…This age disparity may be concordant with the previously published research and attributed to the natural increase in fat mass (approximately 1% per decade) due to sedentary habits, hormonal shifts, and perturbations in fat regulation mechanisms. 14,15 An interesting demographic trend also emerged from our study, pointing to the disparate prevalence of obesity between genders. The gender ratio in the obese group was more balanced at 48.15% male to 51.85% female, contrasting with the predominantly male non-obese group (78.26% to 21.73%).…”

“…This age disparity may be concordant with the previously published research and attributed to the natural increase in fat mass (approximately 1% per decade) due to sedentary habits, hormonal shifts, and perturbations in fat regulation mechanisms. 14 , 15 …”

Lifestyle-related factors in late midlife as predictors of frailty from late midlife into old age: a longitudinal birth cohort study

“…While limited studies include sleep as part of multiple lifestyle factors and frailty [ 7 ], some suggested a higher risk of incident frailty among individuals with poorer sleep [ 6 , 13 ], while others did not [ 7 ]. More studies agree on an association between body anthropometry and frailty [ 8 , 10–12 ], with further evidence suggesting that greater adiposity could further accelerate deficit accumulation [ 28 ]. The association between alcohol consumption and frailty is less clear, with evidence suggesting an association between higher alcohol intake and lower risk of frailty [ 5 , 9 ].…”

The brain insulin receptor gene network and associations with frailty index

“…We have previously reported associations between the hePRS-IR and lower health-related quality of life, impaired glucose regulation and unfavourable cardiometabolic health in women [ 48 ] (in press). Another study using the same study population reported prediction of accelerated age-associated deficits by unfavourable body composition [ 49 ]. Taken together, our current results point to the hePRS-IR being associated with frailty partly through an adverse body composition profile.…”