The burden of prevention: downstream consequences of Pap smear testing in the elderly.

CONTEXT: Although cervical cancer is an unusual cause of death among women 65 and older, most elderly women in the US report continuing to undergo periodic Pap smear screening. OBJECTIVE: To describe the incidence of Pap smears and downstream testing among elderly women. SETTING: Claims-based analysis of female Medicare enrollees age 65 and older. METHODS: Using three years of Medicare Part B 5% Files (1995-1997), we differentiated between women undergoing screening Pap smears and those undergoing Pap smears for surveillance of previous abnormalities or Pap smear follow-up. We determined the proportion of elderly women undergoing Pap smear testing and rates of downstream testing and procedures after an initial Pap smear. RESULTS: Four million female Medicare beneficiaries over 65 years underwent Pap smear testing between 1995 and 1997, representing 25% of the eligible population. After adjusting for underbilling for Pap smears under Medicare, 43% of women over 65 are estimated to have undergone Pap smear testing during the 3-year period. The large majority (90%) of Pap smears were for screening, while 10% were done for surveillance or follow-up. For every 1000 women with a screening Pap smear, 39 had at least one downstream intervention within eight months of the initial Pap smear, including seven women who underwent colposcopy and two women who had other surgical procedures. Rates of downstream interventions were considerably higher for women undergoing Pap smear follow-up (302 per 1000 with at least one downstream intervention), and surveillance of previous abnormalities (209 per 1000 with a downstream intervention). CONCLUSION: Cervical cancer screening is widespread among elderly American women, and follow-up testing is not uncommon, particularly among the ten percent of women who appear to be in a cycle of repeated testing. This substantial volume of testing occurs despite the rarity of cervical cancer deaths and unknown benefits of screening in this age group.

Breast cancer screening.

Randomized controlled trials involving nearly 500,000 women on two continents have confirmed the early promise that screening mammography can reduce breast cancer mortality. The observed benefits of mammographic screening, however, are not the same in all women. The mortality reduction in women over age 70 is unknown, and women aged 40 to 49 do not appear to benefit from mammographic screening to the same extent as those over age 50. The reasons for this disparity are incompletely understood, but it depends in part upon differing tumor biology and mammographic test characteristics in younger women. Even if relative survival benefits were equal for women under and over age 50, absolute reduction in risk would remain considerably lower for younger women, a disparity that would not be corrected by improved screening technology or adjustment of interscreening intervals. The authors' review of the evidence leads them to strongly support mammographic screening of women aged 50 to 69 at an interval not longer than 2 years. The authors also feel it is reasonable to screen women over age 70 who have a favorable life expectancy. They conclude, however, that the evidence does not support a blanket recommendation in favor of screening women aged 40 to 49. Instead, they advocate a well-informed conversation between physician and patient regarding the present knowledge and the risks and benefits of screening for each individual woman. Definitive answers await the results of ongoing RCTs designed to study the survival benefit conferred by screening women aged 40 to 49. Disagreement will undoubtedly persist regarding which recommendations should determine private practice and public policy.