The Safety and Efficacy of Clonidine in Hemodialysis Patients: A Systematic Review and Meta-Analysis

Abstract

Background: Clonidine is a frequently prescribed long-term antihypertensive medication in hemodialysis (HD) patients in the USA, but its safety and efficacy has not been clearly established in the HD population.

Objective: To evaluate, we conducted a systematic review and meta-analysis on the safety and efficacy of clonidine in HD patients.

Methods: Keyword search of "clonidine" and "dialysis" was conducted through April 2021 in PubMed, Cochrane Library, Web of Science, Scopus, and ClinicalTrials.gov databases. Inclusion criteria were as follows - study design: randomized controlled trials, cohort studies, prospective studies, retrospective studies, or case series; subjects: adult HD patients; main outcome: blood pressure (BP) and safety; language: English; and article type: peer-reviewed publications. Studies that examined the effects of clonidine in populations other than adult HD patients were excluded. Meta-analysis was performed on BP reduction outcomes.

Results: Eight studies met the inclusion criteria for the systematic review, including prospective pre-post studies (2), double-blind controlled trial (1), single-blinded placebo-controlled trial (1), crossover open-label clinical trial (1), retrospective analysis (1), and case report series (2). Three studies included in the meta-analysis ranged from 2 to 12 weeks duration, with a collective sample size of 24 (ages 12-77 years). Risk of bias, assessed using the ROBINS-1 tool, was high for all included studies. Significant adverse effects reported included hypotension, light-headedness, drowsiness, dry mouth, rebound hypertension, and contact dermatitis from patch application. Short-term clonidine use was associated with significant improvement in systolic BP (pooled effect: -12.985 mm Hg, 95% CI [-7.878, -18.092], p < 0.001), while changes in diastolic BP were not statistically significant (-11.119 mm Hg, 95% CI [-22.725, 0.487], p = 0.060). No data currently support the long-term efficacy of clonidine in HD patients. This study was unfunded and was developed using PRISMA guidelines and registered on PROSPERO (CRD42018112042).

Conclusions: There is no evidence supporting the long-term use of clonidine in the HD population and a significant side-effect profile. There is low-quality evidence demonstrating the efficacy of clonidine in lowering BP in HD patients in short-term use, but significant safety concerns remain. Fluid removal strategies and other antihypertensives should be used over clonidine for long-term BP control in the HD population.

Keywords: Clonidine; Dialysis; End stage renal disease; Hemodialysis; Hypertension.