Factors Related to Underuse of Surveillance Mammography Among Breast Cancer Survivors

Abstract
Purpose Many older breast cancer survivors do not undergo annual mammography despite guideline recommendations. We identified factors associated with underuse of surveillance mammography and examined whether variation was explained by differences in follow-up care. Patients and Methods We used Surveillance, Epidemiology, and End Results-Medicare data to identify a population-based sample of 44,511 women fee-for-service Medicare enrollees aged ≥ 65 years who were diagnosed with stage I or II breast cancer in 1992 to 1999 who underwent primary surgical therapy. We assessed factors associated with mammography during months 7 to 18, 19 to 30, and 31 to 42 after breast cancer diagnosis using repeated-measures logistic regression; and we examined whether follow-up care with providers of various specialties explained variation in mammography use. Results Only three quarters of women (77.6%) underwent mammography during months 7 to 18 after diagnosis, and only 56.7% had mammography yearly over 3 years. In multivariable analyses, women who were older, black, unmarried, and living in certain regions were less likely than other women to undergo surveillance mammography (all P < .05). Patients with more visits and patients who continued to see a medical oncologist, radiation oncologist, or surgeon were most likely to have mammograms (P < .001); however, adjusting for visits with providers did not explain the lower mammography rates based on age, race, marital status, and geographic region. Conclusion Many elderly breast cancer survivors do not undergo annual surveillance mammography, particularly women who are older, black, and unmarried, and this underuse was not explained by access to follow-up care. New strategies are needed to increase use of surveillance mammography and decrease variations based on nonclinical factors that are likely unrelated to appropriateness of medical care.