VARIABILITY IN MAMMOGRAPHY USE AMONG OLDER WOMEN

OBJECTIVE: To determine rates of and explore factors associated with m ammography use among older women. DESIGN: Retrospective review of part B (physician) bills submitted to Medicare during 1990. SETTING: Healt h Care Financing Administration (HCFA) data, including sociodemographi c information and part B physician bills for all services delivered to Medicare-eligible women in 1990. PATIENTS/PARTICIPANTS: Women age 65 or older as of January 1, 1990, residing in one of 10 states with part B coverage through December 31, 1990. MEASUREMENTS AND MAIN RESULTS: The outcome was receipt of a mammogram (yes/no). We explored factors a ssociated with mammography use within three age groups: 65 to 74, 75 t o 84, and 85+. The factors considered were race, state, median income of ZIP Code of residence (from the 1990 US Census, and used to divide the population into quintiles within each state), and number of primar y care visits (0, 1, 2, and 3+). Overall, 15% of women had a mammogram : 20% of women age 65 to 74, 12% of women age 75 to 84, and 4% of wome n age 85 and older. Mammography use was lowest in Oklahoma and highest in Washington. However, in each state the older the age category, the less the mammography use (e.g., 9% vs 5% vs 2% in Oklahoma and 25% vs 16% vs 5% in Washington for women 65-74, 75-84, and 85+, respectively ). Mammography use was lower for black than for white women age 65 to 74 (14% vs 21%, P < .001) and 75 to 84 (9% vs 12%, P < .001). Women in each of these two age groups had lower mammography use if they reside d in the lowest income quintile and highest if they resided in the hig hest income quintile (17% vs 23% 65-74, and 10% vs 13% 75-84, P values < .001). Among the oldest women (those 85+), mammography use was low (4%) and varied minimally by race and income (P = .907 and .003, respe ctively). In all age groups, mammography use was lowest among women wh o did not have a primary care visit, was greater among women who had a t least one visit, and continued to rise with increasing numbers of vi sits (all P values < .001). For example, among women age 75 to 84, mam mography use increased from 5% to 10%, 14%, and 17% for those with 0, 1, 2, and 3+ visits. CONCLUSIONS: We found that mammography use was le ss for women who were older, of black race, who did not visit a primar y care provider, and who lived in areas with lower median income and c ertain geographic locations (states). Similar factors influenced mammo graphy use in women age 65 to 74, where there is greater consensus as to who should receive a mammogram, and women age 75 to 84, where there is neither consensus nor data. Surprisingly, neither race nor income had much influence on mammography use among women age 85 or older.