Objectives: To compare the efficacy and cost effectiveness of a senna-fibre combination and lactulose in treating constipation in long stay elderly patients.
Design: Randomised, double blind, cross over study.
Setting: Four hospitals in Northern Ireland, one hospital in England, and two nursing homes in England.
Subjects: 77 elderly patients with a history of chronic constipation in long term hospital or nursing home care.
Intervention: A senna-fibre combination (10 ml daily) or lactulose (15 ml twice daily) with matching placebo for two 14 day periods, with 3-5 days before and between treatments.
Main outcome measures: Stool frequency, stool consistency, and ease of evacuation; deviation from recommended dose; daily dose and cost per stool; adverse effects.
Results: Mean daily bowel frequency was greater with the senna-fibre combination (0.8, 95% confidence interval 0.7 to 0.9) than lactulose (0.6, 0.5 to 0.7; t = 3.51 p < or = 0.001). Scores for stool consistency and ease of evacuation were significantly higher for the senna-fibre combination than for lactulose. The recommended dose was exceeded more frequently with lactulose than the senna-fibre combination (chi 2 = 8.38, p or = 0.01). As an index of the standard daily dose, the dose per stool was 1.52 for lactulose and 0.97 for the senna-fibre combination, at a cost per stool of 39.7p for lactulose and 10.3p for senna-fibre. Adverse effects were no different for the two treatments.
Conclusions: Both treatments were effective and well tolerated for chronic constipation in long stay elderly patients. The senna-fibre combination was significantly more effective than lactulose at a lower cost.