The Influence of Risk Factors on Breast Carcinoma Screening of Medicare-insured Older Women

BACKGROUND: It is not certain whether older women with additional breast carcinoma risk factors are adequately screened or whether they are more likely to undergo screening than other older women. This study was conducted to determine whether selected risk factors influence the breast carcinoma screening rates of Medicare-insured older women (i.e., age 65 years or older). METHODS: Self-reported rates of screening mammography and clinical breast examination in the previous year were compared for women with benign breast disease, women with a family history of breast carcinoma, and women lacking these risks, using samples of non-Hispanic white, Medicare-insured women surveyed at the 5 National Cancer Institute Breast Cancer Screening Consortium sites in 1991 (n = 5376, mean age = 69.7 years) and 1994 (n = 5086, mean age = 69.7 years). RESULTS: In 1993, rates of screening mammography reported in the previous year at the 5 Consortium sites had a range of 46-61% for women with a family history of breast carcinoma, 49-66% for women with benign breast disease, and 31-43% for women lacking these risks. Women with a positive family history or a personal history of benign breast disease were also more likely to report having had a clinical breast examination in the previous year and having received a physician's mammography recommendation. A substantial proportion of older women with a positive family history remain inadequately screened, however. Between 25% and 35% of women in this group had not had a screening mammogram in the previous 2 years, while at some Consortium sites more than 20% reported never having had a mammogram in their lives. CONCLUSIONS: Older women with additional risk factors are more likely to undergo screening mammography. This is due partly to more frequent physician recommendations for screening and partly to more frequent provision of clinical breast examinations. However, a substantial proportion of high risk older women remain inadequately screened, despite widespread clinical consensus that these women should be regularly screened. Interventions that target older women with risk factors and their physicians appear warranted. Understanding the mechanisms by which risk factors influence screening is an important area for future research.