EXERCISE, OCCUPATIONAL ACTIVITY, AND RISK OF ENDOMETRIAL CANCER

We conducted a case-control study in western New York state among 232 women with newly-diagnosed endometrial cancer and 631 controls selecte d from the community. Physical activity was measured by participation in vigorous exercise and walking at four time periods: at age 16, and at 20, 10, and 2 years before the interview and by occupational activi ty based on a detailed lifetime history. Women who did a moderate amou nt of vigorous exercise at age 16 and at 20 years before the interview were at reduced risk as compared with those who reported no activity, with odds ratios (OR) (95% confidence intervals) of 0.51 (0.31-0.83) and 0.50 (0.29-0.89), respectively. However, there was no evidence of declining risk with greater amount of activity. At later times, 10 yea rs and 2 years before the interview, being in the highest group with r egard to vigorous activity was associated with a slightly but not sign ificantly lower risk as compared with women who reported no activity; the adjusted OR were 0.72 (0.43-1.19) and 0.67 (0.42-1.09), respective ly. Being in the highest category of miles walked at age 16 (i.e., gre ater than or equal to 15 miles per week) was associated with a slightl y reduced risk as compared with not walking at all (OR 0.64 (0.36-1.16 )), whereas the number of miles walked at other times was not related to reduced risk. Occupational physical activity was not related to the risk of endometrial cancer. Overall, these results indicate that phys ical activity at levels prevalent in this population has at most a mod est relationship to reduced risk of endometrial cancer. (C) 1997 by El sevier Science Inc.