Median nerve swelling is an independent risk factor of carpal tunnel syndrome in chronic hemodialysis patients.

Carpal tunnel syndrome (CTS) has a wide variety of underlying causes and occurs in association with dialysis. Early diagnosis is essential to prevent permanent nerve damage and functional sequelae. We evaluated the association between CTS and cross-sectional area (CSA) of the median nerve in chronic hemodialysis (HD) patients. Patients with end-stage renal disease on maintenance HD via arteriovenous fistula were enrolled. We divided 43 patients into two groups; patients diagnosed with CTS (n = 19) and patients without CTS (n = 24). The median nerve CSA was measured at the wrist (CSA-W) and forearm (CSA-F) by ultrasonography. Median nerve swelling was assessed by the wrist-to-forearm ratio (WFR). There were no significant differences in the underlying causes of chronic kidney disease and adequacy of dialysis between the two groups (p = NS). The patients with CTS showed significantly higher WFR than the patients without CTS (p = 0.001). Univariate Cox regression analysis revealed that WFR >1.25 (odds ratio, 6.30; 95% confidence interval, 1.44-27.45; p = 0.014) was associated with CTS in HD patients. The factors traditionally associated with CTS such as age, sex, diabetes, vintage of HD, β2-MG, intact PTH, and Kt/V were not associated with CTS. After adjustment for age and sex, we found a strong correlation between CTS and the WFR >1.25 (odds ratio, 10.8; 95% confidence interval, 1.85-62.4; p = 0.008). High WFR was associated with the development of CTS, and median nerve swelling was an independent risk factor of CTS in chronic HD patients.