Factors Affecting Changes of Cluster of Differentiation 4 Cell Counts Among Human Immunodeficiency Virus-positive People Who Inject Heroin and Receive Methadone Maintenance Treatment.

Aims: Opioids have been hypothesized to suppress the immune function and worsen outcomes among people living with human immunodeficiency virus (HIV). The study aimed to identify key factors associated with the increased cluster of differentiation 4 (CD4) cell counts among HIV-positive people who inject heroin and receive methadone maintenance treatment (MMT).

Methods: This longitudinal study was conducted at a psychiatric hospital in Northern Taiwan. Participants were recruited from 2006 through 2011, and received CD4 cell counts and HIV viral load monitoring once every 4 to 6 months. Trend in CD4 cell counts, defined as change in CD4 cell count over time, was used as the outcome measure. Independent variables included MMT-related factors and baseline characteristics. Baseline characteristics included age, gender, CD4 cell count, HIV viral load, tests for other infections, liver function tests, and urine drug screens.

Results: Three hundred and fifty one participants were recruited during the study period. The multivariate linear mixed model analysis revealed a higher MMT attendance rate, a higher baseline CD4 cell count, and a shorter duration of MMT were associated with an increase in CD4 cell count over time.

Conclusions: The study showed better adherence to MMT was associated with better preserved immune functions. The negative impact of duration of MMT on CD4 cell counts may be ameliorated by improving the attendance rate, initiation of MMT earlier when the baseline CD4 cell count is still relatively high and by the other beneficial effects of MMT, such as healthier lifestyles with reduced use of short-acting opioids.