Among 570 ART-naïve patients starting therapy between January 1, 2000 and December 31, 2006, 21% (n=121) were treated through a clinical trial and 79% (n=449) through routine care. Patients participated in 13 clinical trials during the study period, including four Adult AIDS Clinical Trial Group (ACTG) studies, which enrolled 86 of the 121 patients (71%) treated through RCTs (). Overall, most patients were between the ages of 30 and 49 (66%), male (77%), black (54%), had no health insurance (37%), and were men who have sex with men (51%). Baseline CD4 values were <200 cells/mm3 in 56% of patients, while a baseline VL <100,000 copies/mL was found in 63% of individuals. Patient histories included diagnoses of affective mental health disorders in 47%, substance abuse in 23%, alcohol abuse in 16% and opportunistic infections in 31%. The most commonly used third drug was a non-nucleoside reverse transcriptase inhibitor (66%) ().
Treatment-naive trials and number of patients enrolled at the University of Alabama at Birmingham 1917 HIV/AIDS Clinic between January 1, 2000 and December 31, 2006.
Table 2 Baseline characteristics and bivariate analysis of factors associated with clinical trial participation among 570 ART-naive patients initiating therapy at the University of Alabama at Birmingham 1917 HIV/AIDS Clinic between January 1, 2000 and December (more ...)
In bivariate analysis, clinical trial enrollment was more common in patients with higher baseline CD4 values (CD4>200 cells/mm3; clinical trial 61% vs. routine care 40%). Black patients were significantly less likely to participate in clinical trials (p<0.001). HIV risk factor impacted study enrollment as well; clinical trial MSM (61%), heterosexual (31%) vs. routine care MSM (49%), heterosexual (44%); p=0.04. However, patient age, sex, baseline VL value, insurance status, affective mental health disorders, substance abuse and alcohol abuse were not associated with clinical trial enrollment ().
Among patients with available viral load measures at 6 months, 66% of those treated through routine care and 71% of those treated through clinical trials achieved virologic suppression (VL<50 copies/mL); at 12 months, 67% and 73% achieved virologic suppression, respectively. In primary multivariable analysis (missing=missing; ), a statistically significant association between method of ART receipt (routine care vs. clinical trial) and virologic failure was not observed at either time point [routine care vs. clinical trial (referent) 6-month OR=1.00, 95%CI=0.54–1.86; 12-month OR=1.56, 95%CI=0.80–3.05]. Six- and 12-month virologic failure was associated with Black race (6-month OR=1.73, 95%CI=1.07–2.82; 12-month OR=2.11, 95%CI=1.27–3.53) and baseline VL>100,000 copies/mL (6-month OR=2.51, 95%CI=1.58–4.01; 12-month OR=1.65, 95%CI=1.01–2.71). Compared to patients with private health insurance, those with public health insurance had higher odds of virologic failure at 6 months (OR=2.06; 95%CI=1.07–3.95), but not at 12 months (OR=1.29; 95%CI=0.66–2.55). When compared to NNRTIs, only un-boosted protease inhibitors had higher odds of 12-month virologic failure (OR=5.24, 95%CI=2.30–11.92). No other study variables were significantly associated with 6- or 12-month virologic failure in primary analyses.
Sensitivity analyses utilizing imputation to assign virologic outcomes to patients with missing values were performed (). In multivariable sensitivity analysis, method of ART receipt (routine care vs. clinical trial) was not associated with virologic failure at 6 months (OR=1.22; 95%CI=0.68–2.19). Though not statistically significant, patients receiving ART through routine care had a trend toward increased odds of virologic failure at 12 months (OR=1.77; 95%CI=0.98–3.23). Additional sensitivity analyses using a missing=failure approach yielded largely consistent findings, although relative to the primary sensitivity analyses, slightly higher (and statistically significant) odds of virologic failure (OR=2.10; 95%CI=1.21–3.66) were observed in the routine care group at 12 months owing to a higher proportion of patients with missing values (data not shown).
The increased odds of virologic failure associated with Black race as well as the use of an unboosted PI (vs. NNRTI ) as a third drug, and the lack of statistically significant associations with age, gender, and history of mental health disorder, substance abuse, or alcohol abuse observed in primary analyses were consistent in sensitivity analyses ().
Finally, univariate and multivariable linear regression analyses of factors associated with 6- and 12-month change from baseline CD4 count value were modeled (missing=missing; ). Baseline VL>100,000 copies/mL was associated with a significantly greater increase in CD4 count (6-month p<0.001, 12-month p=0.03). Twelve months after initiation of ART, no other factors were associated with a difference in CD4 response. Notably, similar CD4 count responses were observed in patients treated through a clinical trial and those treated through routine care. Sensitivity analyses (last value carried forward, ) of CD4 outcomes yielded findings similar to primary analyses.