Cross-sectional study on relationship between constipation and medication in consideration of sleep disorder

Constipation can be caused by adverse drug reactions as a result of many drugs and might be induced by sleep disorders; however, the relative risk of its occurrence with individual drugs and the influence of sleep conditions have not been clarified. To clarify the relationship between constipation and various drugs in consideration of sleep disorders, we investigated the self-reported bowel habits, use of laxatives, and the Athens Insomnia Scale (AIS, a self-administered psychometric instrument to measure insomnia) in 344 inpatients on admission. They were divided into a constipation group (self-reported bowel habits of "Constipation" or "Occasional constipation" and/or use of laxatives, n=161) and a non-constipation group (both "Normal" and the non-use of laxatives, n=183). A comparison of the backgrounds of the two patient groups revealed significant differences in age, gender, number of used drugs, AIS score, hypothyroidism, chronic obstructive pulmonary disease, use of diuretics, coronary vasodilators, thyroid hormones, non-steroidal anti-inflammatory drugs, proton pump inhibitors, antidepressants, anti-anxiety drugs, and hypnotics. Multiple logistic regression analysis using these fourteen factors as autonomous variables showed that age (odds ratio [OR], 1.03; 95% confidence interval [CI], 1.01-1.04; p=0.007), female gender (OR, 1.96; 95% CI, 1.21-3.18; p=0.006), the AIS score (OR, 1.10; 95% CI, 1.02-1.18; p=0.010), and the use of hypnotics (OR, 2.33; 95% CI, 1.30-4.16; p=0.004) were significantly related to constipation; therefore, as hypnotics appear more likely to cause constipation than other drugs, they should be used with caution.