Associations of poor sleep quality, chronic pain and depressive symptoms with frailty in older patients: is there a sex difference?

BACKGROUND: Sleep disturbance, chronic pain and depressive symptoms later in life are modifiable risk factors and may contribute to frailty. However, much less is known about sex differences in the association between these concurrent symptoms and frailty in older patients. Therefore, we conducted this study to explore the associations of poor sleep quality, chronic pain, and depressive symptoms with frailty in older patients, and the sex-specific associations. METHODS: In an observational population-based study, 540 older hospitalized patients from Zhejiang Hospital in China were enrolled. We collected data on poor sleep quality, pain, depressive symptoms and frailty using the Pittsburgh Sleep Quality Index, the Numerical Rating Scale, the 15-item Geriatric Depression Scale, and the Clinical Frailty Scale. Multivariate logistic regression models were used to explore the total sample and sex-specific associations among symptom burdens, symptom combination patterns and symptom counts, and frailty. RESULTS: After adjusting for the potential covariates, concurrent poor sleep quality and depressive symptoms (OR = 4.02, 95% CI 1.57–10.26), concurrent poor sleep quality and chronic pain (OR = 2.05, 95% CI 1.04–4.05), and having three symptoms (OR = 3.52, 95% CI 1.19–10.44) were associated with a higher likelihood of frailty in older inpatients. In addition, older patients with 2 or 3 symptoms (2 and 3 vs. 0 symptoms) had a higher risk of frailty, and the odds ratios were 2.40 and 3.51, respectively. Interaction analysis and sex-stratified associations exhibited conflicting results. The nonsignificant effect of the interaction of sex and symptoms on frailty, but not the sex-stratified associations, showed that individual symptoms, symptom combination patterns, and symptom counts were associated with elevated risks of frailty in older male patients, but not in older female patients. CONCLUSIONS: Increased symptom burdens were associated with a higher risk of frailty in older inpatients, especially in those with poor sleep quality concurrent with at least one of the other two symptoms. Thus, a multidisciplinary program addressing these common symptoms is required to reduce adverse outcomes. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1186/s12877-022-03572-9.