Overweight and obesity as predictors of work-related upper extremity disability among dentists in Arak, Iran: a cross-sectional study

Abstract Background Musculoskeletal disorders (MSDs) pose a significant occupational health challenge for dental professionals due to prolonged static postures and repetitive movements. While obesity is a known risk factor for MSDs, its specific association with upper extremity disability among dentists remains underexplored.To investigate the association between body mass index (BMI) and work-related upper extremity disability among dentists in Arak, Iran. Methods A cross-sectional study was conducted among 276 dentists recruited from dental offices and clinics in Arak using convenience sampling. Data were collected using a demographic and occupational questionnaire, the Nordic Musculoskeletal Questionnaire (NMQ), and the Disabilities of the Arm, Shoulder and Hand (DASH) questionnaire. BMI was categorized according to World Health Organization criteria. Binary logistic regression and chi-square (χ²) tests were employed to determine factors associated with upper extremity disability. Statistical significance was defined as a p-value < 0.05. Results The prevalence of overweight and obesity was 36.6% and 19.2%, respectively. The shoulder was the most frequently affected site (58.7%), followed by the wrist/hand (53.6%) and neck (47.8%). After adjusting for gender, age, and work experience, overweight (adjusted OR = 1.84, 95% CI: 1.02–3.32, p = 0.04) and obesity (adjusted OR = 2.98, 95% CI: 1.42–6.25, p = 0.004) were significantly associated with higher odds of upper extremity disability compared to normal-weight dentists. No significant associations were observed for gender, age, or work experience. Conclusion Elevated BMI is independently associated with upper extremity disability among dentists in a dose-response manner. These findings highlight the need for integrated weight management and ergonomic interventions in occupational health strategies for dental professionals to reduce MSD burden.