Variation in primary care physicians' colorectal cancer screening recommendations by patient age and comorbidity

Screening patterns among primary care physicians (PCPs) may be influenced by patient age and comorbidity. Colorectal cancer (CRC) screening has little benefit among patients with limited life expectancy.

To characterize the extent to which PCPs modify their recommendations for CRC screening based upon patients' increasing age and/or worsening comorbidity

Cross-sectional, nationally representative survey.

The study comprised primary care physicians (n = 1,266) including general internal medicine, family practice, and obstetrics-gynecology physicians.

Physician CRC screening recommendations among patients of varying age and comorbidity were measured based upon clinical vignettes. Independent variables in adjusted models included physician and practice characteristics.

For an 80-year-old patient with unresectable non-small cell lung cancer (NSCLC), 25 % of PCPs recommended CRC screening. For an 80-year-old patient with ischemic cardiomyopathy (New York Heart Association, Class II), 71 % of PCPs recommended CRC screening. PCPs were more likely to recommend fecal occult blood testing than colonoscopy as the preferred screening modality for a healthy 80-year-old, compared to healthy 50- or 65-year-old patients (19 % vs. 5 % vs. 2 % p < 0.001). For an 80-year-old with unresectable NSCLC, PCPs who were an obstetrics-gynecology physician were more likely to recommend CRC screening, while those with a full electronic medical record were less likely to recommend screening.

PCPs consider comorbidity when screening older patients for CRC and may change the screening modality from colonoscopy to FOBT. However, a sizable proportion of PCPs would recommend screening for patients with advanced cancer who would not benefit. Understanding the mechanisms underlying these patterns will facilitate the design of future medical education and policy interventions to reduce unnecessary care.