Association between sarcopenic obesity and risk of frailty in older adults: a systematic review and meta-analysis.

Background: Age-related changes in body composition such as muscle loss can lead to sarcopenia, which is closely associated with frailty. However, the effect of body fat accumulation on frailty in old age remains unclear. In particular, the association between the combination of these two conditions, known as sarcopenic obesity, and frailty in older adults is unclear.

Objective: To synthesise the association between sarcopenic obesity and the risk of frailty and to investigate the role of obesity in the risk of frailty in old age.

Methods: Six databases were searched from inception to 29 September 2024. Two reviewers independently extracted the data and assessed the risk of bias for the included observational studies using the adapted Newcastle-Ottawa scale. The control groups consisted of robust, obese and sarcopenic individuals. Meta-analyses were performed to examine the risk of frailty due to sarcopenic obesity and the role of obesity in frailty amongst sarcopenic older adults.

Results: Sixteen eligible studies were included in meta-analyses from 1098 records. Compared to robust individuals, older adults with sarcopenic obesity were more vulnerable to frailty [odds ratio (OR), 3.76; 95% confidence interval (CI), 2.62 to 5.39; I2 = 79.3%; P < .0001]. Obesity was not associated with the risk of frailty (OR, 1.23; 95% CI, 0.99 to 1.53; I2 = 0.0%; P = .501) in sarcopenic older adults.

Conclusions: Sarcopenic obesity is associated with a high risk of frailty. Sarcopenia and obesity may have synergistic effects on frailty in older adults.