Researchers looking at the spending of some 22,000 Medicare beneficiaries with a depression diagnosis and "Part D" prescription drug benefits found the seniors' use of antidepressants dropped by about 12 percent when they hit the so-called donut hole in drug coverage.

This coverage gap, which earlier research has shown leads seniors to drop heart, diabetes and other types of medications by about the same amount, "poses a serious risk" to those with depression, according to the report published Monday in the Archives of General Psychiatry.

"Beneficiaries with depression reduce their drug use, but it appears they reduce their antidepressants, heart medications and diabetic drugs similarly," Yuting Zhang, the study's lead author and a professor of health economics at the University of Pittsburgh, told Reuters Health.

After a small deductible, the Part D drug plans typically cover 75 percent of drug costs up to a certain dollar figure, which was $2400 in 2007. After a beneficiary reaches that level, there is no coverage until the person has spent potentially thousands of dollars out of pocket, then coverage kicks back in.

That gap, dubbed the donut hole, will eventually be closed by the Affordable Care Act in the year 2020. But until then, Zhang and her colleagues wanted to see how it affects seniors on depression medications. They started by collecting data from 2007 - the year after the Part D program came into existence - on 22,176 Medicare beneficiaries over 65 who spent enough to reach the coverage gap and who had been diagnosed with depression.

Of these, 2,989 people had supplemental coverage that filled in the gap for generic drugs only. Another 11,537 had full drug coverage from other sources, such as low-income subsidies. But 7,650 people had no other coverage when they reached the gap.

Compared to the groups with full drug coverage, the number of antidepressant prescriptions filled by those with no coverage dropped by 12.1 percent in the gap. That compared with a 6.9 percent drop in antidepressant use by those who had generic drug coverage.

The no-coverage group also reduced their use of heart failure drugs by 12.9 percent and of diabetes medications by 13.4 percent. "The coverage gap definitely has an effect," said Zhang, who added that people might stop taking the drugs for different reasons.

Some may wait for their coverage to reset at the end of the year, and some may still have medicine left over and try to make it last, she said. But just stopping antidepressants is dangerous, the authors warn.

"If patients discontinue their appropriate medication therapy abruptly, they could be placing themselves at risk for medication withdrawal effects and for (depression) relapse or recurrence," they write.

Zhang's team looked for consequences from the drop in antidepressant use, but didn't find any signs that people in the no-coverage group were hospitalized or needed medical attention more often than the others.

According to Jack Hoadley, a health policy analyst and researcher at Georgetown University's Health Policy Institute in Washington, D.C., the Affordable Care Act has already made some relief, in the form of rebates and discounts, available to those on Medicare Part D, but the gap remains.

"Right now what's happening is that some people say, 'I can't afford these drugs,' so they stop taking them. So they never really reach the threshold (to receive help) because they stop taking the drug," said Hoadley.

Hoadley, who was not involved with the new research, told Reuters Health that he hopes people eligible for the help with prescription costs are already less likely to stop taking their medications, but it's still too early to tell.

The gap won't be completely closed for several more years, he said.

Zhang told Reuters Health she also thinks the Affordable Care Act will help, "Especially for those that discontinue their drugs because of the costs," she added.

SOURCE: bit.ly/P0ZWgC Archives of General Psychiatry, online July 2, 2012.

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