RESENT AND PAST PHYSICAL-ACTIVITY AND PREVALENCE OF COLORECTAL ADENOMAS

Epidemiological evidence has generally supported a protective associat ion of physical activity with large-bowel adenomas, but whether the pr otective effects are restricted to recent or past activity is uncertai n. We determined whether recent and past recreational or total daily a ctivity was associated with prevalence of colorectal adenomas among ma le and female members of a prepaid health plan in Los Angeles who unde rwent sigmoidoscopy (n = 488 matched pairs). Participants, aged 50-74 years, completed a 126-item semiquantitative food frequency questionna ire and were also interviewed regarding non-dietary risk factors in 19 91-93, In the univariate analysis, all measures of recent recreational physical activity were associated with reduced prevalence of polyps. After adjustment for body mass index, smoking status, daily servings o f fruit and vegetables, use of non-steroidal anti-inflammatory agents and intakes of calories, saturated fat and alcohol, the associations w ere weakened. For subjects engaging in high-intensity activities compa red with subjects not engaging in vigorous activities, the multivariat e odds ratio (OR) for recent recreational activity was 0.7 [95 % confi dence interval (Cl) 0.4-1.1, trend P = 0.08]. Past recreational activi ty and past or recent total daily activity were not associated with pr evalence of adenomas. These results support a modest association of re cent recreational physical activity with prevalence of colorectal aden omas.