RISK FACTORS FOR COST-RELATED MEDICATION NON-ADHERENCE AMONG OLDER PATIENTS WITH CANCER

Purpose:

The cost of prescription drugs remains a barrier to effective medical treatment for many older Americans despite of the establishment of Medicare Part D prescription drug program. Patients with high disease burden are particularly susceptible to cost-related medication non-adherence (CRN) due to high out-of-pocket payments. Although some research based on a small, non-random sample found that a significant portion of cancer patients reported CRN, the prevalence and risk factors for CRN in patients with cancer, a sub-population with very high disease burden and heavy dependence on medication treatment, have not been well-characterized. We sought to assess the prevalence rate and risk factors for CRN among older patients with cancer in the United States using a nationally representative sample.

Method:

We used data from the 2010 Health and Retirement Study, a nationally representative sample of older adults, to assess the prevalence rate and risk factors for CRN including age, health insurance coverage, nursing home residence, functional limitations, and frequency of hospitalization. CRN was self-reported. We conducted multivariate regression analysis to assess the effect of each risk factor.

Result:

Among 2,953 patients who were 50 years or older with previously diagnosed cancer or a malignant tumor excluding minor skin cancer, 293 (9.9%) reported CRN in the past two years. Age less than 65 years, female, lack of health insurance coverage, and frequent hospitalization significantly increased risk for CRN. Limitations in activities of daily living were also associated with increased risk of CRN.  Residence in a nursing home significantly reduced risk.

Conclusion:

These results suggest that, a significant portion of cancer patients have CRN, with sicker patients reporting higher rates of CRN. The life-threatening conditions faced by the patients makes their CRN both more surprising and more concerning. Further research is needed to identify the subgroups of patients with specific type of cancer and the medications that are most likely to be foregone due to CRN in this population. Research is also needed to assess and develop methods to reduce the downstream costs of cost-related medication non-adherence.