Background: Intermittent claudication (IC) is a common problem in older age. New work shows that the administration of glyceryl trinitrate (GTN) can reduce the fall in ankle brachial pressure index (ABPI) after exercise and can increase maximum walking distance by 19% on treadmill exercise. The aim of this study was to further define the clinical benefits of GTN in patients with PVD.
Methods: The study is of a randomised, double-blind, placebo-controlled cross-over design. We studied 29 patients with intermittent claudication where the median age was 67.5 years (45-84). This included 20 males and nine females, and six of these patients were diabetics. To be selected, the patients had to have a history of IC with a resting ABPI of 1.0 or less, that fell by more than 0.1 on exercise. Patients were walked for 15 min on flat ground following GTN spray or placebo and total distances walked were measured. This was then followed by the crossover component of the trial.
Results: Median walking distance with placebo was 825 m (100-1300 m) and with GTN was 900 m (240-1400 m). This is an increase of 9% (p = 0.02, using the Wilcoxon matched pairs signed ranks test).
Conclusion: This study shows a statistically significant improvement in walking distance with GTN in patients with IC.