Adherence Strategies

Simple pill box organizers improve HIV adherence

Pill boxes work for marginally housed, homeless

San Francisco, CA, investigators found a significantly higher adherence among HIV-infected people who used pill boxes, and the same patients had increased viral suppression.

Researchers studied adherence among a cohort of marginally-housed and homeless people in San Francisco, says Maya Petersen, MS, PhD, a medical student at the University of California - San Francisco School of Medicine.

HIV patients were enrolled and followed for several years. Investigators tracked down the participants and conducted unannounced pill counts to measure their medication adherence, Petersen says.

"There are several advantages to unannounced pill counts over other measures," Petersen says. "If you have people come in to the clinic there is an incentive to empty pills ahead of time, and people who self-report often over-report how many pills they've taken."

Investigators collected data on the participants' demographics, viral loads, and CD4 cell counts, as well as their use of recreational drugs, she says.

"We tried to replicate using statistics what we would have seen in randomized, controlled trial," Petersen says. "We needed measurements of all the ways they used pills that might have been different."

Overall, investigators found that participants who used pill boxes were associated with 4 percent higher adherence, as well as increased viral suppression, she says.

"Four percent doesn't sound like a lot, but it is quite a bit in a retrospective study," Petersen says. "It's been associated with an 11 percent reduction in risk progression to clinical AIDS."

The average adherence rate in the entire cohort was 73 percent, Petersen says.

"Those using pill boxes had an 8.8 percent higher adherence," she says. "We didn't take that as the final estimate because it was also true that people who were using pill boxes were in fact different from those who were not using them."

For example, women were more likely to use pill boxes, and people who were homeless were less likely to use them, Petersen explains.

"So we said, 'Women or homeless people might have different underlying abilities to adhere, so we don't want to attribute adherence to them necessarily because of the use of pill boxes,'" she says.

After using various statistical techniques to control for the two groups, the adherence comparison still showed significantly higher adherence for those who used pill boxes, she adds.

On the plus side, pill boxes are very inexpensive, making this step toward improved adherence extremely cost effective, Petersen says.

"When people look in general at interventions to improve adherence, they are quite expensive and involved," she says. "So that's something we thought was exciting about this finding: it's not a piece of high technology, and it costs about $5 at the pharmacy."

Also, there are no apparent risks to people adopting this intervention, and many HIV patients already are using them, including about 60 percent of the cohort studied, Petersen says.

"We think this should be part of routine treatment, not just used when someone is at high risk," Petersen says. "It should be routinely provided by the provider or recommended by the provider."