The authors suggested that the “results of the current study have provided valuable insight into chronic medication adherence and health care use in a low-income population of patients with and without cancer.”
Patient-centered medical homes (PCMHs) were not found to be associated with improvements in chronic disease medication adherence according to a study published in Cancer, however they were associated with lower costs and emergency department visits among some low-income patients with cancer.
In addition, across the studied chronic condition cohorts, researchers noted that medical costs and hospitalizations were found to have increased substantially for patients newly diagnosed with cancer compared with those not diagnosed with cancer.
“The results of the current study have provided valuable insight into chronic medication adherence and health care use in a low-income population of patients with and without cancer,” the authors wrote.
Using a North Carolina cancer registry with linked information and claims data from 2004 to 2010, researchers included Medicaid enrollees who were diagnosed with breast, colorectal, or lung cancer who had hyperlipidemia, hypertension, and/or diabetes mellitus. Using difference-in-difference methods, the investigators then evaluated adherence to chronic disease medications, measured by the change in the percentage of days covered over time among patients with and without cancer. Thereafter, they evaluated whether PCMH enrollment altered the observed differences between those patients with and without cancer again using a differences-in-differences-in-differences approach.
Overall, those with newly diagnosed cancer who had hyperlipidemia were found to have experienced a 7% to 11% decrease in the percentage of days covered compared with patients without cancer. Moreover, patients with cancer also experienced significant increases in medical expenditures and hospitalizations compared with noncancer controls.
Notably, with regard to medication adherence, changes in adherence over time between those with and without cancer were not determined to be statistically significantly different by PCMH status. However, some patients with cancer in a PCMH experienced smaller increases in expenditures (diabetes) and emergency department use (hyperlipidemia), but larger increases in their inpatient hospitalization rates (hypertension) compared with patients with cancer not in a PCMH relative to patients without cancer.
“In sum, particularly within the context of strained financial resources, patients with cancer and their providers may rank statin nonadherence as a lower priority because it does not lead to adverse symptoms and is not detrimental to cancer treatment, whereas monitoring of diabetes and hypertension may influence the quality of life among patients with cancer,” the authors explained. “In future studies, qualitative research identifying the reasons for reductions in statin adherence and the maintenance of antidiabetic and antihypertensive medication adherence would be helpful.”
Importantly though, medication adherence was measured using claims data rather than observing actual medication use. Additionally, the researchers required 12 months of continuous enrollment after diagnosis, potentially biasing the analytic sample because Medicaid patients with discontinuous enrollment (including those who may have died) often are less healthy and have worse outcomes.
“Given the demonstrated potential for low-income patients with cancer with chronic conditions to have worse adherence to their chronic medications, higher costs, and higher health care use around the time of their cancer diagnosis, future studies should examine a variety of approaches that can help to mitigate the multidimensional burden of cancer in low-income populations,” the authors concluded.
Spees LP, Wheeler SB, Zhou X, et al. Changes in Chronic Medication Adherence, Costs, and Health Care Use After a Cancer Diagnosis Among Low-Income Patients and the Role of Patient-Centered Medical Homes. Cancer. doi: 10.1002/cncr.33147