Association between cognitive impairment and oral anticancer agent use in older patients with metastatic renal cell carcinoma

Background Kidney cancer is the fastest‐growing cancer diagnosis in the developed world. About 16% of new cases are stage IV, which has a low five‐year survival rate. Many patients with metastatic renal cell carcinoma (mRCC) are older and may have mild cognitive impairment or dementia (MCI/D). Given prior reports of patients with dementia initiating less cancer therapy and the importance of oral anticancer agents (OAAs) in mRCC treatment, we investigated the prevalence of preexisting MCI/D in patients with mRCC and their OAA use. Methods SEER‐Medicare patients were analyzed who were ≥65 years, diagnosed with mRCC between 2007 and 2015, and had Medicare part D coverage. Patterns and predictors of (a) OAA utilization within the 12 months following mRCC diagnosis and (b) adherence (percent of days covered [PDC] ≥ 80%) during the first 90 days following treatment initiation were assessed. Results Of the 2792 eligible patients, 268 had preexisting MCI/D, and 907 initiated OAA treatment within 12 months of mRCC diagnosis. Patients with preexisting MCI/D were less likely to begin an OAA than those without MCI/D (fully‐adjusted HR 0.53, 95% CI 0.38–0.76). Among OAA initiators, a preexisting MCI/D diagnosis did not alter the likelihood that a person would be adherent (adjusted RR 0.84, 95% CI 0.55–1.28). Conclusions Patients with preexisting MCI/D were half as likely to start an OAA during the year following mRCC diagnosis than patients without comorbid MCI/D. The 90‐day adherence of OAA initiators was not significantly different between those with and without preexisting MCI/D. In light of this, clinicians should assess mRCC patients for cognitive impairment and take steps to optimize OAA utilization by those with MCI/D.