LONG BEACH, CALIF. — About one-quarter of diabetes patients receiving Medicare Part D drug benefits enter the coverage gap—the so-called doughnut hole—that comes after using $2,250 in medications during a single year.
Although some of these patients have supplemental drug coverage that pays for medications in the gap, many do not. Of diabetic patients with no supplemental coverage, 22% report forgoing medications after entering the coverage gap, and 12% report going without food or withholding rent payment to pay for their drugs, Dr. Carol M. Mangione reported at a meeting on diabetes sponsored by the Centers for Disease Control and Prevention.
“Papers in the literature have shown that cost-related nonadherence can lead to increased hospitalizations and mortality with diabetes,” said Dr. Mangione of the University of California, Los Angeles.
She discussed several studies she and her colleagues conducted using data from surveys of Medicare Part D beneficiaries who were enrolled in free-standing or managed care-based plans in eight states during 2006.
Two of the studies focused on patients older than age 65 with evidence of diabetes, and a third included all Medicare Part D patients enrolled in those plans. The investigators focused on drugs for three chronic conditions: diabetes, high blood pressure, and high cholesterol.
In all, 22%–29% of the patients with diabetes entered the gap, and having a coverage gap was associated with a 4%–7% reduction in total drug costs. This is explained at least partly by nonadherence. Beneficiaries who entered the gap were 17% less adherent with respect to their oral diabetes medications than were nongap beneficiaries.
“Some patients have no coverage in the gap, others have generic-only coverage, and some people have full coverage in the gap,” Dr. Mangione said. “Usually the people with full coverage had a retirement benefit that was filling in that gap coverage.”
Having generic-only gap coverage helped somewhat. Significantly fewer patients with such coverage, 17%, reported nonadherence because of cost, compared with 22% with no gap coverage, but the difference in those who reported going without food or not paying rent between those with and without generic-only gap coverage was not significant, at 10% and 12%, respectively. In contrast, only 1% of the patients with full gap coverage reported nonadherence because of cost, and 1% reported going without food or rent.
Patients also engaged in “rational” approaches to contain costs, said Dr. Mangione. Fifty percent of the patients with no gap coverage and 54% of the patients with generic-only gap coverage used mail-order pharmacies because of costs. In contrast, only 9% of patients with full gap coverage used mail-order pharmacies, a significantly smaller proportion.
Similarly, 44% of the patients with no gap coverage and 45% of those with generic-only gap coverage reported switching to generics, compared with 16% of patients with full gap coverage.
In the third study, the investigators asked whether an earlier switch to generic medications could reduce expenditures enough to keep patients out of the gap.
This analysis included all patients who entered the gap during 2006 (with and without diabetes) from one for-profit plan in eight states.
The investigators found that 87% of patients enrolled in freestanding Part D plans and 78% of patients enrolled in managed care Part D plans had at least one possible cost-saving therapeutic substitution.
If generics had been substituted for brand-name medications, the average patient in a freestanding plan would have saved $377, and the average patient in a managed care plan would have saved $293 in the pregap period. Moreover, this switch would have delayed gap entry by slightly more than 1 month.
Dr. Mangione disclosed no conflicts of interest related to her presentation.