Cost disparities in lung cancer treatment by disability status, sex, and race.

BACKGROUND:  The recent literature contains numerous reports of disparities in the diagnosis, treatment, and outcomes of lung cancer across a growing list of population subgroups, including disability status. A common assumption is that disparities stem mainly from variations in the level and type of treatment resources available to specific subgroups. Few studies, however, have directly measured resource differentials. Since policy makers identify reducing health disparities as a critical priority, this study examined whether cumulative Medicare costs (resource consumption) for lung cancer treatment differ across eight patient subgroups defined by disability status, sex, and race.

HYPOTHESIS: Treatment disparities across the eight subgroups will be reflected in variations in the cumulative cost profiles of those subgroups, controlling for other plausible cost drivers. Failure to detect statistically significant differentials in these cost profiles implies that treatment disparities stem from factors other than access to, and utilization of, health care services.

METHODS:  Linked SEER-Medicare data were used to construct cost profiles by service type and treatment phase for roughly 80,000 incident lung cancer cases in patients aged 45 to 85 years at diagnosis. Multiple regression models then tested for cost differentials across the eight subgroups, controlling for various patient and disease characteristics.

Results:  Significant cost differentials were detected, some unanticipated. Women tended to have higher treatment costs than men; they also had more favorable survivals. Nonwhites also tended to have higher treatment costs than whites, although they had significantly shorter survivals. On average, men with disabilities consumed the fewest treatment resources and had the shortest survivals. Mixed results were obtained for women with disabilities.

CONCLUSIONS: Among others, the findings suggest that reducing disparities will take more than just improving access to health care. Special attention must be paid to lung cancer patients with disabilities by both policy makers and clinicians.