Avaliação da S(+) cetamina no tratamento da dor neuropática e qualidade de vida em portadores de hanseníase

Abstract

Neuropathic pain is a chronic pain syndrome of difficult treatment, occurring frequently in patients with leprosy. The objective of this study was to evaluate the therapeutic effect of S(+)-ketamine on neuropathic pain and quality of life in patients with leprosy seen at an outpatient clinic in São Luís - Ma. Experimental study clinical trial, prospective, randomized, double-blind, placebo-controlled trial with 34 patients in a randomized two groups, ketamine and placebo for three months and randomized by sequential numbering. Pain was evaluated using a visual analogue scale (VAS) on six bimonthly visits (1, 2, 3, 4, 5 and 6), and using the DN4 questionnaire on visits 1 and 6, with distribution of S (+)-ketamine and rescue analgesic and adverse effects assessed at each visit. Blood (15ml) was drawn from patients for safety tests on visits 1 and 6, and on visits 1, 2, 4 and 6, to cytokines IL-1, IL-6 and TNFα. Quality of life was also evaluated using WHOQOL-Bref on visits 1 and 6. Results showed most subjects female, age 18 and 29 years of age, pardo ethnicity, single, income between 2 and 4 minimum salaries, and a mean 7.78±2.21 years of education. In the assessment of pain by VAS both groups showed a reduction in mean pain scores over time, and showed statistical significance p <0.05. However there was no statistical difference in pain scores between groups and also in relation to the use of analgesic medication (codeine). There was significant reduction in DN4 score in the placebo group compared to the initial and final evaluations compared to ketamine, although the initial DN4 scores were significantly lower in the placebo group, the assessments before and after the use of S (+)-ketamine. In evaluating the quality of life in the physical, psychological, social relationships and environment, there was no statistically significant difference between groups. The amounts of IL-1, IL-6 and TNF-α in serum of four collections of ketamine and placebo groups showed no statistically significant difference both in assessing intragroup along the visits as between groups. Regarding adverse effects, there was a statistically significant predominance in the ketamine group especially for dizziness, visual changes and other effects. We conclude that the S (+)-ketamine orally at the dose used in leprosy patients and neuropathic pain was not superior to placebo for the analgesic effect and impact on quality of life.