Depression has a significant impact on adherence to antiretroviral therapy, according to a meta-analysis published in the online edition of the Journal of Acquired Immune Deficiency Syndromes.
The results of 95 studies involving 36,000 patients were examined by investigators, who comment “depression is consistently associated with nonadherence to HIV treatment.”
Depression was associated with poorer adherence in cross-sectional and longitudinal studies, in both resource-rich and resource-poor settings, and in all populations affected by HIV.
“Interventions that target depressive symptoms and optimal utilisation of HAART [highly active antiretroviral therapy] may have maximal effects on health outcomes,” write the authors.
HIV therapy works best if all or nearly all of the recommended doses are taken correctly. However, many patients have difficulty adhering to their therapy, and poorer adherence has been associated with an increased risk of treatment failure.
Missing occasional doses of medication is usually due to simple forgetfulness and is unlikely to have any clinical significance. However, poorer adherence can be related to social circumstances or co-morbid conditions, including mental health problems.
Depression and depressive symptoms are common in patients with HIV, with some studies finding a prevalence of 36%.
Many studies have looked at the relationship between depression and poor adherence to HIV therapy, but until now there has been no meta-analysis of their results, evaluating the strength and consistency of their findings.
Therefore a team of investigators lead by Dr Jeffrey Gonzalez of the Albert Einstein College of Medicine, New York, conducted a literature search to identify studies published since 1996 that examined the impact of depression or depressive symptoms on adherence.
A total of 95 studies involving over 36,000 patients met their inclusion criteria.
Overall, the studies showed a highly significant relationship between depression and non-adherence (p < 0.0001).
The overall effect of depression on adherence was relatively modest (0.19). However, the investigators note that it was of a similar magnitude to that observed in a separate meta-analysis into the effect of depression on adherence in other chronic illnesses.
Studies that measured adherence by interview found a significantly stronger relationship between depression and non-adherence that studies employing self-completed questionnaires (p = 0.03).
Depression was equally likely to affect adherence in cross-sectional and longitudinal studies.
Even mild symptoms of depression were associated with poorer adherence, the investigators commenting, “Our findings also suggest that the relationship between depression and HAART nonadherence is not limited to comparisons between those who meet the criteria for clinical depression and those who do not…studies that focused on depression diagnosis found equivalent effects to studies that measured depression as a degree of symptom severity.”
However, the meta-analysis was not able to show how depression affects adherence.
The researchers speculate that it could be related to its impact on concentration, appetite, self-worth, or self-care.
They conclude, “novel approaches to the successful management of these linked problems could have significant public health benefits for patients living with HIV/AIDS."
Gonzalez JS et al. Depression and HIV treatment nonadherence. J Acquir Immune Defic Syndr, online edition, doi: 10.1097/QAI.0bo13e31822d490a, 2011 (click here for the free abstract).