Nifedipine vs Placebo for Treatment of Chronic Chilblains: A Randomized Controlled Trial

Abstract

Purpose: Nifedipine is commonly prescribed for the treatment of chilblains (pernio, perniosis) on the basis of observational studies and a single small, older clinical trial. We aimed to confirm the proposed superiority of oral nifedipine 60 mg per day over placebo for treatment of chronic chilblains in primary care.

Methods: We performed a randomized, placebo-controlled, double-blind, crossover trial, closely following the design of the older trial. A total of 32 patients with chronic chilblains were randomly assigned to nifedipine (30 mg controlled release twice a day) or placebo. The primary outcome was patient-reported complaints; the secondary outcome was patient-reported disability. Both were assessed from daily ratings on 100-mm visual analogue scales recorded in a diary. We took ambient temperatures into account and checked for a carry-over effect, and monitored for adverse effects.

Results: After 6 weeks of treatment, mean scores on the visual analogue scale on complaints showed a nonsignificant difference of 1.84 mm (95% CI, -6.67 to 2.99 mm) in favor of nifedipine (P = .44). Mean scores on the visual analogue scale on disability showed a nonsignificant difference of 0.56 mm (95% CI, -2.97 to 4.09 mm) in favor of placebo (P = .75). There was no carry-over effect of prior study treatment. Nifedipine was associated with significantly lower systolic blood pressure and a significantly higher incidence of edema.

Conclusions: In our study, nifedipine was not superior to placebo for treating chronic chilblains. These findings contrast with those of the older study and do not support routine use of nifedipine for this condition.

Keywords: chilblains; nifedipine; practice-based research; primary care; randomized controlled trial; therapeutics.

Figure 1

Flowchart of patients in the trial.

Figure 2

Patient-reported scores for complaints (VOC) and disability VOD (not corrected for temperature) for each arm and study phase. VAS = visual analogue scale; VOC = visual analogue scale on complaints; VOD = visual analogue scale on disability. Notes: Scores measured on 100-mm scales where higher values indicate more complaints (symptoms) or greater disability. Phase 0: no-treatment baseline; phase 1: first assigned treatment; phase 2: second assigned treatment.