Influence of exercise activity on quality of life in long-term breast cancer survivors.

BACKGROUND: Behavioral and lifestyle factors may influence quality of life (QOL) outcomes in breast cancer survivors. METHODS: Information on QOL (Short Form-36, SF-36), lifestyle and survivorship was collected during telephone interviews with 374 breast cancer patients, diagnosed between 1983 and 1988 at ages 40 years or younger and interviewed, on average 13.2 years following diagnosis. These women previously participated in a case-control study soon after their diagnoses, providing information on breast cancer risk factors including exercise activity. We examined the impact of changes in exercise activity (comparing pre- to post-diagnosis levels) on the SF-36 mental and physical health summary scales using regression analyses. RESULTS: A positive change in exercise activity was associated with a higher score on the SF-36 physical health summary scale at follow-up (p = 0.005). Change in exercise activity was not associated with the SF-36 mental health summary scale score. Patients who increased their activity levels did not differ from those who did not in terms of medical or demographic characteristics. CONCLUSION: This study provides one of the longest follow-up periods of breast cancer survivors to date among studies that focus on QOL and is unique in its focus on women diagnosed at a young age. Our results confirm high levels of functioning and well-being among long-term survivors and indicate that women whose exercise activity increased following diagnosis score higher on the SF-36 physical health summary scale. These findings suggest a potential role for exercise activity in maintaining well-being after a cancer diagnosis.

Induced abortion, miscarriage, and breast cancer risk of young women.

Early studies of breast cancer raised substantial concern regarding risk associated with induced abortion and miscarriage. Literature reviews suggest that study findings depend heavily on the comparison group and that the use of parous women as a reference group for nulliparous women may artificially inflate risk. To examine the individual effects of induced abortion and miscarriage on breast cancer risk of parous and nulliparous women, 744 patients < or =40 years of age and diagnosed from 1983-1988 were matched by parity, age, and race with controls living in the same neighborhood in Los Angeles County. In-person interviews were conducted to obtain a detailed reproductive history. Risk estimates were obtained by conditional logistic regression using nulligravid women as the reference group for nulliparous women with a history of incomplete pregnancy and parous women with no incomplete pregnancies as the reference group for parous women with a history of incomplete pregnancy. Breast cancer risk of parous women was unrelated to a history of miscarriage or induced abortion. Breast cancer risk was reduced among nulliparous women with a history of induced abortion relative to nulligravid women, although the risk estimate was imprecise. Risk declined as the number of induced abortions increased (P = 0.04). Our results do not support the hypothesis that induced abortion or miscarriage increase the breast cancer risk of young women.