Quinine for nocturnal leg cramp in the elderly
Clinical bottom line:Based on a small number of patients, quinine sulphate (200 to 300 mg/day) reduces number of nocturnal leg cramps, but not severity or duration in general ambulatory people. Number of nights with cramps was also reduced. The benefit of quinine appeared to be cumulative, and should therefore be taken regularly. However, patients should be monitored for adverse effects.
Nocturnal leg cramps are painful involuntary muscle cramps that occur when the patient is recumbent. They are extremely common in the elderly (more than 70%), and a variety of non-pharmacological and pharmacological treatments have been investigated. Quinine has been suggested as the most effective pharmacological treatment available, but its safety profile has been called into question.
Systematic review
Man-son-Hing M, Wells G. Meta-analysis of efficacy of quinine for treatment of nocturnal leg cramps in elderly people. BMJ. 1995; 310, 13-7.
Date review completed: April 1994
Number of trials included: 6
Number of patients: 107
Control group: placebo
Main outcomes: reduction in number of leg cramps over four weeks, severity and duration of cramps and cramp index (duration x severity)
Inclusion criteria were randomised, double-blind placebo controlled trials of quinine for nocturnal leg cramps; general ambulatory patients (non-dialysis); crossover design.
Point estimates with 95% confidence intervals were calculated for the main outcomes where data were available. Chi-square was used where individual patient data were not available.
Findings
Six trials, predominantly in elderly populations looked at the effects of between 200 and 300 mg/day of quinine sulphate over two to four weeks.
Number of cramps over four weeks
Five trials in 82 patients reported on the absolute change in cramp numbers. For trials of less than four weeks, weekly rates were used to estimate number of cramps over four weeks. Combined absolute reduction was 8.83 (4.16 to 13.49), indicating significant benefit with quinine. Two of the five trials showed a significant reduction in number of cramps with quinine sulphate, two showed no difference, and one extremely small trial did not report on individual patients, but an estimated rate did not change overall findings. (This small trial did not change findings on any other outcome, and is not therefore described again). Reviewers note that the longer term trials (four weeks) showed benefit, whereas two week trials did not.
Severity of cramps over four weeks
Three trials in 70 patients provided data on this outcome using different scales. Reviewers converted all scales to a 3 point scale (mild moderate or severe). Combined absolute change in severity indicated no difference between quinine and placebo, -0.048 (-0.314 to 0.218) units on a 3 point scale.
Number of nights with cramps
Two trials in 51 patients reported on this outcome, both showing a significant reduction. The combined data showed a 27.5% (-30.6 to -24.4) reduction on this measure.
Duration of cramps
Two trials in 24 patients provided data on this outcome, and the combined results indicate no significant change, -20.8 (-43.7 to 2.1) minutes in duration of individual cramps with quinine versus placebo.
Cramp index
Three trials in 46 patients provided data on this outcome, and the combined results indicate no significant change, 5.25 (-10.43 to 20.93) units.
Adverse effects
Six trials in 107 patients reported on serious adverse effects. One patient on quinine experienced nausea, myalgia, leucopenia and thrombocytopenia that resolved three days after quinine discontinuation. A small number of patients reported minor adverse effects with quinine.
Further reading
Related topics
Identifier CP109-3304 QUININE FOR NOCTURNAL LEG CRAMP: Jan-2000