Relationship Between Obesity and Severity of Carpal Tunnel Syndrome in Tanzania

Carpal tunnel syndrome (CTS) is the most common focal mononeuropathy in the general population, and obesity is one of its established independent risk factors The prevalence of obesity in CTS patients and its association with CTS severity are yet to be fully studied among Tanzanians. In this study, we determined the frequency of obesity in patients with CTS and its relationship with the electrophysiological severity of CTS in a Tanzanian private tertiary level hospital. This is a retrospective observational and analytical study of patients referred for electrodiagnostic (EDX) evaluation of suspected CTS at the clinical neurophysiology laboratory of the Aga Khan Hospital, Dar es Salaam, Tanzania. All EDX studies done for CTS indications between August 1, 2017, and December 31, 2019, were reviewed. The frequency of CTS patients with obesity (body mass index >30 kg/m²) and overweight (25.0-29.9 kg/m²) was determined. Next, we explored the relationship between obesity and the electrophysiologic severity of CTS. One-hundred nine hands were studied. The prevalence of obesity was 50.5% and overweight was 31.2%. Females were significantly more obese than males (P = 0.001). Many of the EDX parameters that defined CTS, including prolonged median nerve sensory and distal motor latencies as well as sensory conduction velocity, were significantly more abnormal in the obese when compared to the nonobese patients. On univariate analysis, severe CTS (stage 5) was commoner among nonobese patients (P = 0.031), while moderate CTS (stage3) was more prevalent among obese patients (P < 0.001). Multivariate regression analysis, however, revealed no effect of obesity on CTS severity (P = 0.490). Obesity and overweight are prevalent among this cohort with CTS, but did not predict severe CTS. The use of other indices of adiposity may show a trend.