Association between Cervical Curvature and Sleep Factors among Chinese Adult Population

Background: Cervical curvature plays a key role in supporting the head and enabling neck movements. Its alteration is linked to neck pain and musculoskeletal disorders. Sleep-related factors can influence cervical alignment, yet their effects remain underexplored. This study investigates the association of sleep factors with cervical curvature to inform preventive strategies and clinical guidance.
Objective: To assess the association between sleep factors like sleeping position, duration, and pillow height with cervical curvature among the adults undergoing cervical spine MRI.
Methods: This study was hospital based and cross-sectional. It was conducted among 610 adults. The participants were of 30-59 years age. They were attending a tertiary care Chinese hospital for cervical spine MRI. A validated literature based questionnaire was used to collect the data related to sleep factors, socio-demographic, ergonomic, and lifestyle variables. Cervical curvature was evaluated using MRI-based Cobb angle measurement from cervical spine C2-C7. Cervical spine curvature was classified based on the Cobb angle a ‘lordotic’ type if the angle was between >7° and <20°, as “normal”, and a ‘straight’ type if it is between > -7° and <7°, and a ‘kyphotic’ type if it is -7° or less, both combined as “abnormal”. Multivariable logistic regression was performed to estimate adjusted odds ratios (aORs) with 95% confidence intervals (CIs).
Results: Most of the participants exhibited normal curvature (62%). Female participants had significantly higher odds of abnormal cervical curvature compared to males (adjusted OR = 2.9, 95% CI: 2.0-4.2, p < 0.001), after adjusting for other covariates. Participants with abnormal sleep duration had higher odds of abnormal curvature compared to those with normal sleep (adjusted OR = 1.4, 95% CI: 0.9-1.9, p = 0.05) after adjusting.
Conclusion: Cervical curvature is independently associated with sleep duration but not sleep position and pillow height. Maintaining normal sleep duration may represent modifiable strategies to support long-term cervical spine health. Longitudinal studies are required to establish causality.