Factors Associated with Sustained Virologic Suppression in Patients Receiving Antiretroviral Therapy in an Urban HIV Care Clinic

Abstract

Clinical trials commonly measure rates of virologic suppression at a specific time point, whereas sustained virologic suppression is the goal of highly active antiretroviral therapy (HAART). We explored factors associated with sustained virologic suppression in an urban clinic population. The study population was drawn from patients who enrolled in Montefiore Medical Center's Infectious Diseases Clinic from 1999 to 2000. A computerized query of the hospital information system generated a list of potential case patients having every HIV- 1 viral load (VL) less than 50 copies per milliliter throughout 2002 (at least three VL measurements were required), and a list of potential controls who failed to demonstrate sustained virologic suppression during 2002. Demographic and clinical information were collected by chart review, and case and control patient characteristics were compared by both univariate and multivariate analyses. Sixty-four case patients were compared to 64 controls. There were no significant differences in age, gender, ethnicity, type of antiretroviral therapy, or frequency of clinic visits. During the year of the study, cases experienced a significantly greater rise in CD4(+) lymphocyte counts than controls (108 cells per microliter versus 27 cells per microliter). On univariate analysis, factors associated with sustained virologic suppression included risk behavior other than heterosexual contact or injection drug use, being a non-smoker, and hepatitis C seropositivity. On logistic regression analysis, factors independently associated with sustained virologic suppression were risk behavior other than heterosexual contact or injection drug use (IDU), and hepatitis C seropositivity. In this study sample, being a nonsmoker, having a risk behavior for HIV acquisition other than heterosexual contact or IDU, and being seropositive for hepatitis C were associated with sustained virologic suppression. Computerized query of the hospital information system proved to be a powerful tool for the identification of study patients in a real-world clinic environment.