Rewarding HIV-positive illegal drug users for taking prescribed medications on time may be the best way to increase their adherence to the strict regimen required by cutting-edge highly active antiretroviral therapy (HAART), reported University of California, San Francisco psychologist James Sorensen, PhD, at APA's 2004 Annual Convention in Honolulu.
He pointed to an as yet unpublished study--conducted at the San Francisco Treatment Research Center with a grant from the National Institute on Drug Abuse--in which he and his colleagues required 33 opiate-dependent HIV-positive participants to attend biweekly coaching sessions that taught patients the importance of taking HAART medications at nearly the same times twice daily. During these sessions, the medication coach emphasized that missed or late doses allow the virus to develop resistance to the chemicals.
Another group of 33 participants received identical counseling, but also participated in a behavioral reward system. Researchers asked these patients to place one of their HAART medications in a pill bottle equipped with a computerized cap that recorded the date and time the patient opened it. The patients also visited the researchers' office about once a week to receive payment, in the form of a grocery or drugstore voucher, for the number of times they took their medications at the correct time.
The amount of payment increased each consecutive day the patient took the medication promptly. For example, the first on-time dosage garnered only $1, but on the fourth consecutive day, the patient received $5.20. If a dose was missed, the payment dropped to $1, regardless of the previous number of days a patient had taken medications on time up to that point.
Prior to the intervention, both groups took their medications promptly about 50 percent of the time, but midway through the 12-week program, the group receiving payments upped their adherence rate to 78 percent. In comparison, those that received only medication coaching took their HAART medications on time 56 percent of the time, on average.
Unfortunately, after the intervention, both groups returned to taking medications promptly only 50 to 60 percent of the time, Sorensen reported. But despite the limitations, paying patients for taking their medications may be a good strategy in certain situations if health-care organizations were willing to foot the bill, he said.
"Voucher reinforcement...could be useful for patients on the cusp of adequate adherence," said Sorensen. "It also might be better for time-limited medications, such as some hepatitis C medications, which are taken for six months."