A new UCLA study finds that doctors who follow guidelines recommending the delay of antiretroviral therapy for non-adherent HIV patients are likelier to put off that treatment for Latinos, women and poor patients than they do for others. In addition, doctors are slower to prescribe protease inhibitors for African American patients whether or not the physician follows the guidelines.
The study, "Disparities in HIV Treatment and Physician Attitudes About Delaying Protease Inhibitors for Non-Adherent Patients," was published in the April 2 issue of the Journal of General Internal Medicine. Dr. Mitchell D. Wong, assistant professor of medicine in the division of general internal medicine and health services research at the David Geffen School of Medicine at UCLA, led the study.
"HIV rapidly develops resistance to treatment when patients repeatedly miss doses of their medications," Wong said. "Thus, current national HIV treatment guidelines recommend that physicians consider their patients' readiness to be adherent to their medication regimen when deciding whether or not to start HIV treatment. We examined data from a nationally representative sample of patients with HIV and their physicians and found that most physicians agree with this prescribing guideline. Furthermore, we found that this prescribing practice appears to account for the relatively later use of antiretroviral treatment among Latinos, women, and the poor.
"Our study suggests that physicians should take extra care in assessing and improving patient adherence among women, Latinos and the poor in order to eliminate disparities in treatment among these groups," he said.
The study analyzed data on 367 physicians and 1,717 patients who were eligible for protease inhibitor treatment. The physicians and patients were surveyed between January 1996 and January 1998.
Some 89 percent of the physicians said that patient adherence is important in their decision to prescribe protease inhibitors, according to the study. These physicians were categorized as selective providers. The 11 percent who disagreed that adherence is important were categorized as non-selective. Previous studies suggest that providers often base their assessments of the likelihood of adherence on superficial evidence. For instance, physicians predicted that African Americans and injection drug users were less likely than other groups to adhere to their treatment, basing this assessment only on demographic and disease severity information.
"We found (protease inhibitor) use was later for Latinos, women and those with less income," the authors wrote in the study. "However, these differences occurred only if patients had a selective provider and not a non-selective provider. African Americans appeared to use (protease inhibitors) later than whites regardless of providers' prescribing attitude."
Though some segments of the population may indeed be less adherent when it comes to sticking to a regular drug regimen, prompting physicians to save therapy for when the patient truly needs it, growing evidence also suggests that physicians are unable to accurately assess adherence. "Their assessments might incorporate subtle biases that could explain some of the disparities we observed," the researchers wrote in the study. "If so, delaying antiretroviral treatment may contribute to inequitable care."
Still, delaying treatment for non-adherent patients did not appear to be either harmful or beneficial, neither in terms of health status nor mortality, Wong noted. "Future studies need to look further into whether delaying treatment based on a patient's likely adherence helps to delay the development of HIV resistance to medications or improves health outcomes," he said.
Funding for the study came from grants from the Agency for Healthcare Research and Quality, The Robert Wood Johnson Foundation, the Universitywide AIDS Research Program and the Health Resources Service Administration through a National Research Service Award.
In addition to Wong, other UCLA researchers included Dr. William E. Cunningham, associate professor in the schools of medicine and public health; Dr. Martin F. Shapiro, professor in the schools of medicine and public health and chief of the division of general internal medicine and health services research; Ronald M. Andersen, professor in the School of Public Health; Naihua Duan, professor in the department of psychiatry; Honghu Liu, assistant adjunct professor in the school of medicine; and Dr. Neil S. Wenger, associate professor in the school of medicine and co-director of the Rand Corp.'s Southern California Evidence-Based Practice Center.