Measured over a nine-month treatment course, the young people who were
coached took the highest average number of pills compared to the self-esteem
and usual care groups.
The study, by researchers from the Center for Behavioral Epidemiology
and Community Health at San Diego State University, appears in the November
issue of the American Journal of Public Health.
Poor adherence — not taking medications as prescribed — is
a major medical problem. The World Health Organization estimates that
patients take only half of the drugs that doctors tell them to. The problem
is especially
bad with tuberculosis. Failing to take the full course of medication
can lead to development of the disease in people with inactive tuberculosis
infection. It can also contribute to drug-resistant strains of the disease-causing
organism.
The prevalence of tuberculosis in the Latino community is twice that of
the general rate in the United States. So researcher Melbourne F. Hovell,
Ph.D., M.P.H., and colleagues recruited 286 Latino adolescents in the San
Diego area with latent tuberculosis infection to test which approach might
work best to encourage the teens to take their medicine.
All the adolescents were prescribed the drug isoniazid, taken once a day.
The teens were randomly divided into three groups. One group got usual
medical care: six to nine months of drug treatment, with return clinic
visits scheduled at one- to three-month intervals.
Along with their prescriptions, the second group received special coaching
in adherence to their medications. Their coaches were bilingual Latino
college students specially trained to educate the young patients about
tuberculosis infection and treatment. The coaches helped the teens set
adherence goals, followed by five 30-minute in-person sessions and seven
15-minute telephone sessions during the next six months. Counselors discussed
why pills were taken or missed and how the teenagers could improve adherence.
The third group also received isoniazid and was assigned to self-esteem
counselors. The counselors encouraged the adolescents to talk about relationships
and communications with family and friends and about cultural identity.
The self-esteem counselors provided no information or advice about tuberculosis,
referring any questions about the disease to physicians.
Unannounced monthly interviews and urine tests were used to check whether
the teens were taking their pills.
“We believe that the combination of random urine assays and detailed
interview measures provides the most accurate estimate of isoniazid adherence,” Hovell
says.
Results showed that the group coached for adherence took more pills on
average than the comparison groups. Patients given the usual medical care
took 150 pills on average (out of a possible 270 pills) over the nine-month
period. The self-esteem group took an average of 155 pills, but the coached
group took an average of 180 pills.
The researchers note that the results raise questions about the true levels
of adherence found in previous studies and in clinical practice. Participants
in the study had lower adherence rates than reported by other investigators,
but that may be due to the stricter measurement procedures.
Half of the coached group completed treatment (defined as taking 180 pills
within 270 days), indicating that more effort might be required, Hovell
says.
“These results suggest that more powerful interventions are needed
to achieve at least 90 percent treatment completion rates among Latino
adolescents,” he says. “Coaching of longer duration might
result in substantially higher completion rates.”
This research was funded by grants from the National Heart, Lung and Blood
Institute, the Alliance Healthcare Foundation, and the Universitywide AIDS
Research Program of the University of California.
