Carpal tunnel syndrome severity and work: a case-control study

Background: Carpal tunnel syndrome (CTS) is a socially relevant condition. Risk factors associated with CTS severity and work have not been explored. Aims: This case-control study aims to investigate the association between CTS severity and occupational biomechanical overload considering personal anthropometric risk factors. Methods: We consecutively enrolled one CTS case for two controls. CTS cases were grouped into three classes of progressive clinical and electrophysiological severity according to two validated scales. Job titles were coded according to the International Standard Classification of Occupations (ISCO 88) and grouped into two broad socio-occupational categories: blue-collar and white-collar workers.The associations between CTS (or CTS severity) and blue-collar status were assessed using unconditional (or multinomial) logistic regression models adjusted for age, gender, centre and two anthropometric indexes: wrist-palm ratio and waist-stature ratio. Odds ratios (OR) or relative risk ratio and 95% confidence intervals (95% CI) were calculated, as appropriate. Results: We included 183 cases and 445 controls. Blue-collar status was a risk factor for CTS (OR 2.4; 95% CI 1.5-3.8). Among job titles, vine and/or olive tree growers (OR 6.0; 95% CI 2.0-17.9) and food processing workers (OR 4.8; 95% CI 1.5-15.2) were at higher risk. At multinomial logistic regression analysis, blue-collar status and the two anthropometric indexes were associated with moderate/severe CTS, after mutual adjustment. Conclusions: Blue-collar workers showed a higher risk of CTS than white-collar workers, adjusting for anthropometric and body measures as well. Preventive interventions should be addressed to decrease the biomechanical overload of the upper limbs and limit the overweight.