BOWEL HABIT IN RELATION TO AGE AND GENDER - FINDINGS FROM THE NATIONAL-HEALTH INTERVIEW SURVEY AND CLINICAL IMPLICATIONS

Background: Constipation is widely considered to be a common problem a mong the elderly, as evidenced by the high rate of laxative use in thi s population. Yet, age-related prevalence studies of constipation gene rally do not distinguish between actual alteration in bowel movement f requency and subjective self-report of constipation. Objective: To det ermine the relationship between advancing age and bowel habit. Methods : We employed data collected on 42 375 subjects who participated in th e National Health Interview Survey on Digestive Disorders based on int erviews with a random nationwide sample of US households. We examined the following characteristics reported by this population according to selected age groupings by decade: constipation, levels of laxative us e, and two bowel movements per week or less. Results: Contrary to conv entional wisdom, there was no age-related increase in the proportion o f subjects reporting infrequent bowel movements. Nonetheless, the prev alence of self-report of constipation increased with advancing age, wi th a greater proportion of women reporting this symptom than men acros s all age groups. Laxative use also increased substantially with aging ; while women were more likely to use laxatives than men, this effect attenuated with advancing age. A U-shaped relationship was observed be tween advancing age and bowel habit in men and women; 5.9% of individu als younger than 40 years reported two bowel movements per week or les s compared with 3.8% of those aged 60 to 69 years and 6.3% of those ag ed 80 years or older. This relationship persisted after adjusting for laxative use. Conclusion: These findings suggest that a decline in bow el movement frequency is not an invariable concomitant of aging. In el derly patients who report being constipated, it is essential to take a careful physical, psychological, and bowel history rather than to aut omatically assume the need for laxative use.