Association of early and late onset of chronic diseases with physical frailty among older Indian adults: study based on a population survey

Background: There is a limited understanding of the age at onset of chronic diseases linked to an increased risk of physical frailty among older persons, despite the well-established link between chronic diseases and frailty. This study aimed to examine the prevalence of early- and late-onset chronic diseases and their association with physical frailty and its components in older adults in India. Methods: Data from the Longitudinal Aging Study in India (LASI), wave 1 (2017–2018), were used with a sample of 31,386 older adults aged 60 years and above, including 15,043 males and 16,343 females. Physical frailty was assessed by using an adapted version of the frailty phenotype developed by Fried et al. The main explanatory variable was self-reported age at the onset of chronic diseases, and a cutoff of 50 years was considered to define the early and late onset of chronic disease. Multivariable logistic regression models were used to examine the association between early and late onset of chronic diseases and physical frailty and its components. Results: Overall, 30.65% of the sample population was physically frail, and frailty was much higher in the 80 years and aboveage group (54.23%). Compared to individuals without any morbidity, those with late onset of single morbidity (AOR: 1.22, CI: 1.09–1.36) and multimorbidity (AOR: 1.49, CI: 1.29–1.71) had higher odds of physical frailty. Similarly, multimorbidity was significantly associated with most components of physical frailty, with the exception of weight loss. Older adults with late-onset hypertension (AOR: 1.22, CI: 1.09–1.36), stroke (AOR: 1.75, CI: 1.35–2.27), and heart disease (AOR: 1.58, CI: 1.21–2.06) had higher odds of physical frailty than those without any morbidity. The odds of being physically frail were higher in those with early onset arthritis (AOR: 1.55, CI: 1.15–2.08) and late-onset of arthritis (AOR: 1.35, CI: 1.13–1.61) than in those without any morbidity. Additionally, the odds of physical frailty were higher among those with late-onset chronic diseases, particularly heart disease (AOR: 3.39, CI: 1.31–8.77) and psychiatric disease (AOR: 3.00, CI: 1.19–7.61), compared to individuals with early onset of these conditions. Conclusions: This study found significant positive associations between early and late onset chronic diseases and physical frailty and its components among older Indians. These findings underscore the importance of managing late-onset chronic diseases, especially heart diseases and psychiatric conditions, to mitigate frailty in older adults. These findings also emphasize the critical role of age at onset of specific chronic conditions and multimorbidity in the development of frailty, suggesting that targeted disease-specific interventions could help delay or prevent frailty.