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

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.