Meta-Analysis of the Relationship Between HIV Infection and Risk for Depressive Disorders
Jeffrey A. Ciesla, M.A. John E. Roberts, Ph.D.
Objective: Each of 10 published studies investigating the relationship between HIV infection and risk for depressive disorders concluded that HIV-positive individuals are at no greater risk for depression than com- parable HIV-negative individuals. This study used meta-analytic techniques to further examine the relationship between depressive disorders and HIV infection.
Method: Meta-analytic techniques were used to aggregate and reanalyze the data from 10 studies that compared HIV-posi- tive and HIV-negative individuals for rates of major depressive disorder (N=2,596) or dysthymic disorder (N=1,822).
Results: The frequency of major depres- sive disorder was nearly two times higher
in HIV-positive subjects than in HIV-nega- tive comparison subjects. On the other hand, findings were inconclusive with re- gard to dysthymic disorder. Rates of de- pression do not appear to be related to the sexual orientation or disease stage of infected individuals.
Conclusions: Although the majority of HIV-positive individuals appear to be psy- chologically resilient, this meta-analysis provides strong evidence that HIV infec- tion is associated with a greater risk for major depressive disorder. Future re- search should focus on identifying path- ways of risk and resilience for depression within this population.
(Am J Psychiatry 2001; 158:725–730)
R ecent estimates suggest that more than 30 million people are living with HIV infection worldwide (1). With the help of new medical treatments, a large percentage of these individuals have been able to lead otherwise healthy lives for many years. Nonetheless, infected individuals face the prospect of social stigma, long-term physical dis- comfort and illness, and eventual death. Given this state of chronic stress for infected individuals, researchers have been naturally concerned about their psychological ad- justment to living with this disease. Because depressive disorders have been shown to be closely associated with a number of other serious medical illnesses (2, 3), rates of depression have been of considerable interest.
Over the past 15 years, several studies have estimated the frequency of depressive disorders, particularly major de- pressive disorder, in HIV-positive populations. These rates have differed dramatically, from 0% (4) to 47.8% (5). Yet, rates of depression in HIV-negative comparison groups matched on relevant characteristics (e.g., gender, sexual orientation, and drug use) also have differed widely. It is surprising that each of 10 studies published between 1988 and 1998 that compared rates of current depressive disor- ders between HIV-positive and HIV-negative groups con- cluded that HIV infection is not associated with a higher rate of the disorder (4, 6–14). These consistent null findings have led investigators to conclude that risk for clinically significant depression is not affected by HIV infection. As Rabkin (15) stated, “In none of the reviewed studies is the
difference in one-month prevalence rates between HIV- positive and HIV-negative samples statistically signifi- cant…. HIV status is not by itself a strong predictor of mood or anxiety disorders” (pp. 163–165). Likewise, Lyket- sos et al. (16) noted, “Rates of depressive disorder are not clearly increased compared to the general population in the early and middle stages of infection” (p. 218).
Unfortunatel , each of these 10 studies had low statisti- cal power, failing to include enough participants to detect anything but a very large effect of HIV status. Statistical tests involving the prediction of one dichotomous variable (presence or absence of depressive disorder) from another dichotomous variable (presence or absence of HIV) re- quire very large numbers of participants to provide ade- quate power. For example, assuming a 5% base rate of major depressive disorder in the relevant comparison community, a sample size of approximately 140 partici- pants is needed to detect reliably (alpha=0.05; beta=0.80) a threefold increase in the risk for depression. To detect a twofold increase, a sample size of approximately 400 indi- viduals would be required. Unequal numbers of partici- pants in the HIV-positive and HIV-negative groups would necessitate even larger samples (17).
Only one of the reviewed studies (11) would have been able to detect a twofold increase in risk for depression among HIV-positive individuals. However, this study did not capitalize on the relatively large size of its study group. Instead, data from its five different study locations were
Am J Psychiatry 158:5, May 2001