They found that 16 percent of enrollees entered the gap, with nearly 3 percent entering the gap very early on, i.e. within the first 180 days. Of those who entered the gap, only 7 percent exited again. Women and patients with dementia and diabetes were the most likely to enter the gap. Other conditions also predisposed beneficiaries to gap entry, including end-stage renal disease, coronary artery disease, chronic obstructive pulmonary disease, mental health conditions, and congestive heart failure.

As an example, an average 67-year-old woman with diabetes and a typical set of comorbidities - hypertension, hyperlipidemia, coronary artery disease and depression - would have a 54 percent chance of falling into the Medicare Part D coverage gap and being exposed to the full cost of her medication. If she fell into the gap, she would have an 11 percent chance of exiting again, but in the meantime, she would have incurred more than $3,600 in total out-of-pocket drug expenses.

The authors conclude: "Our findings suggest that medication cost-counseling interventions focusing on these clinically vulnerable subpopulations may be warranted. Physician-patient discussions about the expense and undesirable side effects of particular medications are one approach to managing outpatient drug therapy and controlling costs."

Source: Springer