Postural abnormalities and functional impairment in hemodialysis and peritoneal dialysis patients: a cross-sectional study

Abstract

BACKGROUND: Postural abnormalities, particularly thoracic hyperkyphosis and forward head posture (FHP), are increasingly recognized as prevalent yet under-investigated complications in patients with end-stage renal disease (ESRD). Such deformities are associated with impaired gait, balance, and overall functional capacity. This study aimed to determine the prevalence of thoracic hyperkyphosis and FHP among hemodialysis (HD) and peritoneal dialysis (PD) patients and to explore their associations with key physical performance measures. METHODS: In this cross-sectional study, 276 ESRD patients (184 HD patients, 92 PD patients) were analyzed following propensity score matching. Thoracic hyperkyphosis was assessed via a Flexicurve ruler, and FHP was quantified via craniovertebral angle photography. Functional performance was evaluated via the timed up and go (TUG) test, the 6-minute walk test (6MWT), and gait speed (GS). Multivariate logistic regression models were applied to identify demographic, behavioral, and clinical correlates of postural abnormalities and to evaluate their relationships with impaired functional outcomes. RESULTS: After propensity score matching, the prevalence of hyperkyphosis was 63 in HD patients and 65 in PD patients, whereas FHP was observed in 57 and 55, respectively, with no statistically significant difference between dialysis modalities. Older age (> 65 years) and prolonged dialysis duration (>/= 12 months) were significantly associated with a higher likelihood of both postural abnormalities (all p < 0.05). Extended sedentary time (>/= 7 h/day) showed the strongest association, increasing the odds of hyperkyphosis (OR = 1.9, 95 CI: 1.5-4.1) and FHP (OR = 1.5, 95 CI: 1.2-3.4, both p < 0.05). Among HD patients with hyperkyphosis, 87 exhibited impaired TUG performance, and 94 covered < 375 m in the 6MWT (both p < 0.001), whereas 65 and 70 of PD patients presented similar impairments (both p < 0.05). Gait speed impairment was observed in 92 of HD patients and 67 of PD patients with hyperkyphosis (both p < 0.05). CONCLUSION: Thoracic hyperkyphosis and FHP were highly prevalent in both HD and PD patients and were associated with impaired mobility and functional performance. These findings underscore the importance of integrating routine postural and functional assessments into dialysis care to facilitate early identification of high-risk individuals and guide preventive and rehabilitative strategies aimed at improving patient outcomes and quality of life. TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT06350552, Registered on 06/03/2024. Registered trial name: Investigating the Prevalence of Hyper Kyphosis and Forward Head Posture in Dialysis Patients.