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 enrolled in free-standing or managed care-based plans in eight states during 2006. Two of the studies focused on patients aged older than 65 years with evidence of diabetes, and a third included all Medicare Part D patients enrolled in those plans.
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 non-gap beneficiaries.
“Some patients have no coverage in the gap, others have generic-only coverage, and some people have full coverage,” Dr. Mangione said.
Having generic-only gap coverage helped somewhat. Significantly fewer patients with such coverage, 17%, reported nonadherence due to cost, than the 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 due to 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.
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.
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 drugs, the average patient in a freestanding plan would have saved $377; the average patient in a managed care plan would have saved $293 in the pregap period.
Dr. Mangione disclosed no conflicts of interest related to her presentation.