Assessing the effectiveness of topical betamethasone to treat chronic chilblains: a randomised clinical trial in primary care.

BACKGROUND: GPs prescribe topical corticosteroids to patients with chronic chilblains despite poor evidence for their effectiveness. The authors of the current study therefore decided to assess the effectiveness of topical steroids in a primary care setting. AIM: To assess the effectiveness of topical application of betamethasone valerate 0.1% cream in patients with chronic chilblains. DESIGN AND SETTING: A placebo-controlled, double-blind, crossover, randomised clinical trial in a Dutch primary care setting. METHOD: The study population consisted of 34 participants suffering from chronic chilblains. Intervention was topical application of betamethasone valerate 0.1% cream twice a day for 6 weeks compared with placebo. Primary outcome was the visual analogue scale on complaints (VOC). Secondary outcome was the visual analogue scale on disability (VOD). Both were assessed with a diary of daily scores on a 100 mm visual analogue scale. The authors took ambient temperatures into account, checked for a carry-over effect, performed additional analysis, and monitored adverse effects. RESULTS: On the primary outcome mean VOC, there was a difference of 0.56 mm (95% confidence interval [CI] = -2.88 to 3.99 mm) in favour of placebo (P = 0.744). On the secondary outcome mean VOD, there was a difference of 0.88 mm (95% CI = -2.22 to 3.98 mm) in favour of placebo (P = 0.567). This study found no carry-over effect and no adverse effects. CONCLUSION: In this study, topical betamethasone was not superior to placebo in the treatment of chronic chilblains. Topical betamethasone should not be used for chronic chilblains without new evidence.

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

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.

Phenotypic familial aggregation in chronic chilblains.

BACKGROUND: Our clinical observations and two earlier studies indicate familial clustering to be involved in chronic chilblains. Demonstrating phenotypic familial aggregation is a next step to investigate the origin of familial clustering. OBJECTIVE: This study was initiated to assess evidence for phenotypic familial aggregation in chronic chilblains. METHODS: Using a case-control family design in a primary care setting, we computed the familial relative risk of at least one episode of chronic chilblains during life with 95% confidence intervals (CIs). The study population consisted of 192 relatives of 31 case probands (at least one confirmed episode of chronic chilblains). The control population consisted of 178 relatives of 31 sex- and age-matched index controls (no history of chronic chilblains). RESULTS: The familial relative risk of chronic chilblains was 3.6 (95% CI 1.9-7.3). Additional sensitivity analysis shows similar figures. CONCLUSION: We demonstrate robust phenotypic familial aggregation in chronic chilblains.