Associations between biomarkers, muscle function, dynapenia status, fall risk, depressive symptoms, and sleep quality in patients with lower limb osteoarthritis: a cross-sectional study

Lower limb osteoarthritis is common in older adults. It is associated with pain, functional decline, and psychological distress, all of which can impair sleep. However, few studies have comprehensively examined the biological, functional, and psychosocial factors associated with sleep quality in this population. The present cross-sectional study explored the associations between sleep quality and sociodemographic characteristics, biomarkers, muscle function, dynapenia, fall risk, and depressive symptoms in older adults with lower limb osteoarthritis scheduled for joint replacement surgery. Statistical analyses included chi-square or Fisher’s exact tests for categorical variables (e.g., sex, marital status, and education level), independent-samples t-tests or Mann–Whitney U tests for continuous variables (e.g., biomarkers, gait time, and fall risk scores), and multivariable logistic regression analyses to identify factors independently associated with poor sleep quality. Among the 114 participants, 55.3% had poor sleep quality. Poor sleep quality was more prevalent among women, participants who were widowed or divorced, and those with lower educational attainment. In the bivariate analyses, compared with participants with good sleep quality, those with poor sleep quality had lower hemoglobin (Hb) levels (12.66 ± 1.31 vs. 13.59 ± 1.38 g/dL), lower glycated hemoglobin (HbA1c) levels (5.79 ± 0.89 vs. 6.15 ± 0.66%), higher C-reactive protein (CRP) levels (0.27 ± 0.59 vs. 0.12 ± 0.15 mg/dL), longer 6-meter gait times (9.93 ± 6.03 vs. 7.91 ± 4.29 s), and higher fall risk scores (9.21 ± 4.49 vs. 7.02 ± 3.76). Multivariable logistic regression analysis revealed that lower Hb levels (odds ratio [OR] = 0.64, 95% confidence interval [CI] = 0.45–0.91), lower HbA1c levels (OR = 0.57, 95% CI = 0.33–0.99), and higher fall risk scores (OR = 1.14, 95% CI = 1.02–1.28) were independently associated with poor sleep quality. Sleep quality in older adults with lower limb osteoarthritis is associated with multiple biological, functional, and sociodemographic domains. Lower Hb levels, lower HbA1c levels, and higher fall risk were independently associated with poorer sleep quality. These findings highlight the need for a multidimensional assessment approach for evaluating sleep quality in this population. Additional prospective and multicenter studies are required to confirm the observed associations before routine clinical implementation.