Abstract
BACKGROUND: Guidelines recommend informed decision-making regarding prostate specific antigen (PSA) screening for men with at least 10 years of remaining life expectancy (RLE). Comorbidity measures have been used to judge RLE in previous studies, but assessments based on other common RLE measures are unknown. We assessed whether screening rates varied based on four clinically relevant RLE measures, including comorbidities, in a nationally-representative, community-based sample. METHODS: Using the National Social Life, Health and Aging Project (NSHAP), we selected men over 65 without prostate cancer (n=709). They were stratified into three RLE categories (0-7 years, 8-12 years, and 13+ years) based on validated measures of comorbidities, self-rated health status, functional status, and physical performance. The independent relationship of each RLE measure and a combined measure to screening was determined using multivariable logistic regressions. RESULTS: Self-rated health (OR = 6.82; p < 0.01) most closely correlated with RLE-based screening, while the comorbidity index correlated the least (OR = 1.50; p = 0.09). The relationship of RLE to PSA screening significantly strengthened when controlling for the number of doctor visits, particularly for comorbidities (OR= 43.6; p < 0.001). Men who had consistent estimates of less than 7 years RLE by all four measures had an adjusted PSA screening rate of 43.3%. CONCLUSIONS: Regardless of the RLE measure used, men who were estimated to have limited RLE had significant PSA screening rates. However, different RLE measures have different correlations with PSA screening. Specific estimates of over-screening should therefore carefully consider the RLE measure used.