Integrating age and comorbidity to assess screening mammography utilization

Abstract

Background: Most studies use age as a cutoff to evaluate screening mammography utilization, generally examining screening up to age 75 years (the age-cutoff method). However, many experts and guidelines encourage clinicians to consider patient health and/or life expectancy.

Purpose: To compare the accuracy of estimating screening mammography utilization in older women using the age-cutoff method versus using a method based on the projected life expectancy.

Methods: Two cohorts were selected from female Medicare beneficiaries aged 67-90 years living in Texas in 2001 and 2006. The 2001 cohort (n=716,279) was used to generate life-expectancy estimates by age and comorbidity, which were then applied to the 2006 cohort (n=697,825). Screening mammography utilization during 2006-2007 was measured for the 2006 cohort. Data were collected in 2000-2007 and analyzed in 2011.

Results: The screening rate was 52.7% in women aged 67-74 years based on age alone, compared to 53.5% in women in the same age group with a life expectancy of ≥7 years. A large proportion (63.4%) of women aged 75-90 years (n=370,583) had a life expectancy of ≥7 years. Those women had a screening rate of 42.7%. The screening rate was 35.7% in women aged 75-90 years based on age alone, compared to 16.3% in women in the same age group with a life expectancy of <5 years.

Conclusions: Estimating screening mammography utilization among older women can be improved by using projected life expectancy rather than the age-cutoff method.