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Etiology

Physical activity and fiber prevented diverticular disease in men

ACP J Club. 1995 July-Aug;123:23. doi:10.7326/ACPJC-1995-123-1-023

Related Content in the Archives
• Correction: Physical activity and fiber prevented diverticular disease in men


Source Citation

Aldoori WH, Giovannucci EL, Rimm EB, et al. Prospective study of physical activity and the risk of symptomatic diverticular disease in men. Gut. 1995 Feb;36:276-82.


Abstract

Objective

To determine whether physical activity or dietary factors are associated with symptomatic diverticular disease in men.

Design

6-year cohort study of men in the Health Professionals' Follow-up Study.

Setting

U.S. community-based study.

Participants

51 529 men between 40 and 75 years of age who were health professionals and who responded to a mailed questionnaire in 1986. Exclusion criteria were missing dietary information, abnormal caloric consumption (< 800 or > 4200 kcal/d), a history of cancer, colon or rectal polyps, ulcerative colitis, or diverticular disease before 1988. 47 678 men were included. Follow-up was 94%.

Assessment of risk factors

Self-reported physical activity and weekly frequencies (walking, stair-climbing, cycling, rowing and calisthenics, jogging and running, swimming, and racquet sports) were analyzed in quintiles of activity. Data on total energy intake, body mass index, height, vitamin and mineral supplements, and fiber consumption were taken from questionnaires.

Main outcome measures

Self-reported symptomatic (presenting with pain, change in bowel habits, or bleeding) diverticular disease on 1990 and 1992 questionnaires confirmed by a supplementary questionnaire.

Main results

382 cases of symptomatic diverticular disease were documented. Multivariate-adjusted total energy intake and height were not associated with diverticular disease. Compared with men in the lowest quintile of physical activity, men in the highest quintile had a lower relative risk (RR) for diverticular disease (RR 0.63, 95% CI 0.45 to 0.88). Most of the risk reduction was attributable to vigorous activity (RR 0,60, CI 0.41 to 0.87). After adjusting for age, jogging and running (P for trend = 0.03)was also associated with a decreased risk for diverticular disease. Television and video watching (an indicator of inactivity) was associated with an increased risk for diverticular disease (P for trend = 0.006). Multivariate analysis controlling for age and total fat intake showed that men in the lowest quintile for both dietary fiber and physical activity had an increased risk for symptomatic diverticular disease (RR 2.56, CI 1.36 to 4.82).

Conclusion

Physical activity, especially vigorous activity, and a high-fiber diet were associated with a decreased risk for diverticular disease in men.

Source of funding: National Institutes of Health.

For article reprint: Dr. W.H. Aldoori, Whitehall-Robins Inc, Canada. FAX: 905-507-7115.


Commentary

Diverticulosis is an extraordinarily common accompaniment to aging in the United States; its prevalence rises to 66% by 85 years of age (1). This far exceeds the figures seen in developing nations and among vegetarians in the United Kingdom (2).

The negative association between dietary fiber and diverticular disease is well established, although its mechanism is not entirely clear. Now we are presented with evidence that physical activity is also negatively linked with diverticular disease. This well-designed trial by Aldoori and colleagues attempts to correct for ascertainment bias and the possibility that physical activity merely covaries with fiber intake; that is, that those who are diet conscious also tend to exercise more. Their results suggest that lack of exercise is an independent risk factor for symptomatic diverticular disease in men.

Does physiologic evidence support this association? Perhaps. Diverticular disease is epidemiologically linked to another malady of the Western colon, constipation. How? Both occur in the same populations and are associated with fiber-deficient diets. Interestingly, constipation is known to be negatively associated with physical activity (3); running tends to increase propagated colonic contractions (4) and may speed colonic transit (studies are mixed). Thus, vigorous physical activity conceivably could protect against diverticular disease through effects on constipation, intraluminal pressure, or colonic transit times.

As it now stands, this new finding in male health professionals awaits a definitive explanation or, at least, confirmation. Because many good and sufficient reasons already exist for recommending physical activity to our patients and all others, there seems to be no harm in tentatively adding this one to the list.

Lawrence Cheskin, MD
Johns Hopkins School of MedicineBaltimore, Maryland, USA


References

1. Parks TG. Natural history of diverticular disease of the colon. Clin Gastroenterol. 1975;4:53-69.

2. Gear JS, Ware A, Fursdon P, et al. Symptomless diverticular disease and intake of dietary fibre. Lancet. 1979;1:511-4.

3. Everhart JE, Go VL, Johannes RS, et al. A longitudinal study of self-reported bowel habits in the United States. Dig Dis Sci. 1989;34:1153-62.

4. Cheskin LJ, Crowell MD, Kamal N, et al. The effects of acute exercise on colonic motility. Journal of Gastrointestinal Motility. 1992;4:173-7.