Participant Characteristics by HIV and HAART status.

Means (SD), median (25th –75th percentile), or proportions. PI = protease inhibitor; NNRTI = non-nucleoside reverse transcriptase inhibitor; NRTI = nucleoside reverse transcriptase inhibitor. aP-values are for comparison of HIV− to HIV+ participants. bP-values are for comparison of HIV+/HAART+ to HIV+/HAART− participants. cIllicit drug use was defined as any use of marijuana, nitrite inhalants, crack or cocaine, stimulants, or other illicit drugs since the last MACS visit. *P < 0.05, compared to HIV−. †P < 0.05, HIV+/HAART+ compared to HIV+/HAART−. Comparisons of data represented with means were performed using t-tests for 2-group comparisons and linear regression with robust estimation of the standard errors. Comparisons of data represented by medians were performed using the Wilcoxon ranksum test for 2-group comparisons. Comparisons of categorical data represented by percent were performed using chi-square analysis and Fisher’s exact test.