Dynapenia-abdominal obesity and mortality risk, is independent effect obscured by age and frailty?:Birjand Longitudinal Aging Study (BLAS).

Abstract

Background: Abdominal obesity and low muscle strength, known separately as risk factors for mortality, might have a synergistic effect when they co-occur. Dynapenic abdominal obesity (DAO) is a condition defined by the presence of both. However, DAO's independent and combined impact on mortality remains under investigation.

Objective: The objective of the present study was to evaluate the association of dynapenia, abdominal obesity, and dynapenic abdominal obesity with all-cause mortality among community-dwelling older adults.

Methods: This is a longitudinal study with a 5-year follow-up conducted involving 1,354 community-dwelling older adults (≥ 65 years) of the Birjand Longitudinal Aging Study (BLAS). Abdominal obesity and dynapenia were respectively defined based on waist circumference (> 102 cm for men and > 88 cm for women) and grip strength (< 26 kg for men and < 16 kg for women). The sample was divided into four groups: non-dynapenic/non-abdominal obesity (ND/NAO), dynapenic/non-abdominal obesity (D/NAO), non-dynapenic/abdominal obesity (ND/AO), and dynapenic/abdominal obesity (D/AO). The outcome was all-cause mortality registered through four methods: 1- telephone interview with the family of the participants during September 2018 and February 2024, 2- hospital information systems, 3- death registry of the deputy of the Health of Birjand University of Medical Sciences 4- in a subject who died at home or out of hospital death registry was verified by a verbal autopsy performed by a clinician. Univariate and multiple Logistic regression models were used to estimate the risk of all-cause mortality as a function of dynapenia and abdominal obesity in competing events controlled by age, sex, multi-morbidity, and frailty.

Results: The mean age of the study participants was 69.77 ± 7.55 years, and about 703 (51.71%) were female. There was a statistical difference between the alive and the deceased groups in terms of sex, age, multimorbidity, and frailty. Mortality was statistically higher among dynapenic participants (P < 0.001). Unadjusted logistic regression analysis explored the relationship between D/NAO and mortality (OR = 2.18; CI 95% 1.25-3.78). In the adjusted models, no significant relationships were observed. Age and frailty had significant associations with mortality.

Conclusion: While our study found an association between dynapenia without abdominal obesity and increased mortality risk, factors like age and frailty might play a stronger role. These require further investigation to understand the independent effect of dynapenia on mortality fully.

Graphical abstract:

Supplementary information: The online version contains supplementary material available at 10.1007/s40200-024-01501-8.