Proportion of patients with cancer among high-cost Medicare beneficiaries: Who they are and what drives their spending.

BACKGROUND: A small proportion of patients account for the majority of health care spending. Of this group, little is known about what proportion have a cancer diagnosis and how their spending pattern compares to those without cancer.

METHODS: Using national Medicare data of enrollees 65 or older, we identified patients in the top decile of spending in 2014 and designated them as high-cost. We used ICD-9 codes to identify patients with a cancer diagnosis and examined cancer prevalence among both high-cost and non-high-cost patients. We examined patterns of spending for high-cost patients with and without cancer.

RESULTS: While 14.8% of all Medicare beneficiaries have a cancer diagnosis, we found that the prevalence of a cancer diagnosis was much higher among high-cost patients (32.5% versus 12.9% of non-high-cost patients). Thus, having a cancer diagnosis was associated with a 3.1 times greater odds of being high-cost, even after accounting for age (odds ratio 3.09, 95% CI 3.07-3.11; P < 0.001). High-cost patients with cancer had higher total annual spending than high-cost patients without cancer ($66,685 vs. $59,427; p < 0.0001); costs among high-cost cancer patients were driven by greater use of outpatient treatments (19.2% of total spending vs. 13.6% among non-cancer high-cost patients, p < 0.0001) and more prescription drugs (11.9% vs. 9.9%; p < 0.0001).

CONCLUSIONS: There is a high prevalence of cancer diagnoses among high-cost Medicare patients.

IMPLICATIONS: Programs that target high-cost patients may need to customize interventions based on whether the patient has a cancer diagnosis.