MONTREAL — Hypertensive patients who have depression are less likely to stick to their therapy regimen than are those who are not depressed or are in remission from depression, according to a study of 161 patients.
“This suggests that any change in depressive symptomatology over time can affect medication adherence and may be clinically important,” Sara Gallagher said at the annual meeting of the Society of Behavioral Medicine.
Her study was embedded in a randomized, controlled trial of the effect of motivational interviewing on medication adherence (Am. J. Hypertens. 2008;21:1137-43). The 161 hypertensive African Americans in the study were followed in primary care practice. The patients had a mean age of 54 years, and 87% of them were women. Depressive symptomatology was assessed at baseline and at 6 and 12 months using the Center for Epidemiologic Studies–Depression Scale (CES-D).
A total of 44% of the patients were classified as nondepressed, with a CES-D score of less than 16 at all time points, while 19% were considered depressed, with a score of 16 or above at all time points. The remaining 37% of the patients were classified as in remission, meaning that they progressed from depressed to nondepressed during of the study, said Ms. Gallagher, of New York (N.Y.) University.
Medication adherence was assessed at baseline and at 12 months using the self-reported Morisky scale. At baseline, 64% of the study population reported nonadherence to their medication, and this dropped to 48% at the end of the study.
A multivariate analysis revealed that depressive symptoms were associated with medication nonadherence, Ms. Gallagher reported.
Among the depressed patients, only 34% reported adherence at 12 months, compared with 66% of those in the nondepressed group and 47% of those who were in remission.
The study confirms previous findings that depressive symptoms are associated with poor medication adherence, Ms. Gallagher said. However, the finding that remission of depressive symptoms is associated with improved adherence suggests a benefit to addressing patient depression in this context, she said.