Efficacy of Oral Pregabalin versus Narrowband Ultraviolet B Therapy in Patients with Uraemic Pruritus: A Randomised Clinical Trial

Introduction: Uraemic pruritus is a common and distressing symptom experienced by patients with Chronic Kidney Disease (CKD). It affects 15-49% of patients with predialysis CKD and 50-90% of those undergoing dialysis. Uraemic pruritus significantly impairs the quality of life of these patients; however, well-designed clinical trials evaluating effective treatment options remain limited. Although studies have demonstrated the benefits of pregabalin and Narrowband Ultraviolet B (NBUVB) phototherapy, limitations such as small sample sizes, methodological variability, and lack of long-term follow-up highlight the need for further research, particularly studies comparing systemic therapies with phototherapy. Aim: To compare the efficacy and assess the adverse effects of oral pregabalin and NB-UVB phototherapy in the treatment of uraemic pruritus. Materials and Methods: This randomised clinical trial was conducted in the dermatology outpatient department of Madras Medical College, Chennai, Tamil Nadu, India from September 2020 to August 2021. The study included 30 patients in each treatment group. Patients aged over 18 years, diagnosed with CKD, presenting with symptoms of uraemic pruritus, and willing to give informed consent were included. Patients younger than 18 years, those with acute illness, liver cirrhosis, or decompensated heart failure were excluded. Additionally, patients allergic to pregabalin, those with a history of photosensitivity, pruritus due to secondary causes, and pregnant or lactating women were excluded. The intensity of pruritus was assessed using the Visual Analogue Scale (VAS). Group A received oral pregabalin 75 mg on alternate nights for 12 weeks, while group B underwent NBUVB phototherapy with the dose titrated upward over the same duration. Patients in both groups were followed-up fortnightly during the 12-week treatment period and subsequently on a monthly basis until the 24th week. Statistical analysis was performed using the Statistical Package for the Social Sciences (SPSS) version 23.0. The Chi-square test was used to compare qualitative variables between the two groups, and the independent sample t-test was used to compare mean values. A p-value of <0.05 was considered as statistically significant. Results: The mean age of the participants was 48.01±12.66 years. Male predominance was observed in both groups, accounting for 63.3% in group A and 53.3% in group B. Both groups showed a similar distribution in terms of age, gender, mean duration and intensity of pruritus, and mean estimated Glomerular Filtration Rate (eGFR) (p-value>0.05). The mean baseline VAS score was 8.89±0.69 in the pregabalin group and 8.73±1.07 in the NB-UVB group. At the end of the followup period, the mean VAS score in the pregabalin group was significantly lower than that in the NB-UVB group (p-value=0.001). Pruritus relapse was observed eight weeks after the final dose of oral pregabalin in group A. Both treatment modalities were associated with minimal adverse effects. Conclusion: A faster and more pronounced reduction in mean VAS scores was observed in patients treated with pregabalin compared to those receiving NB-UVB phototherapy. The adverse drug reactions observed in this study were minimal.