Continuous Retention and Viral Suppression Provide Further Insights Into the HIV Care Continuum Compared to the Cross-sectional HIV Care Cascade

Abstract

Background: The human immunodeficiency virus (HIV) care continuum has become an important tool for evaluating HIV care. Current depictions of the care continuum are often cross-sectional and evaluate retention and viral suppression (VS) in a single year, yet the National HIV/AIDS Strategy calls for programs with long-lasting outcomes.

Methods: Retrospective chart review of HIV-infected patients enrolled in a large, urban clinic in 2010 followed longitudinally for 36 months. McNemar comparisons and logistic regression analyses were conducted to evaluate covariate association with continuous retention and VS. Generalized estimating equation log-linear models were used to integrate time into the model.

Results: Among 655 patients (77% male, 83% black, 54% men who have sex with men (MSM), 78% uninsured) continuous retention/VS at 12 months (84%/64%), 24 months (60%/48%), and 36 months (49%/39%) showed significant attrition (P < .0001) over time. Continuous retention was associated with prevalent VS at the end of 36 months (adjusted prevalence ratio 3.12; 95% confidence interval [CI], 2.40, 4.07). 12-month retention for black (84%) and nonblack (85%) patients was equivalent, yet fewer blacks (46%) than nonblacks (63%) achieved 36-month continuous retention due to a significant interaction between race and time (aOR 0.75, 95% CI, .59, .95).

Conclusions: Continuous retention is a critically important measure of long-term success in HIV treatment and the crucial component of successful treatment-as-prevention but is infrequently evaluated. Single cross-sections may overestimate successful retention and virologic outcomes. A longitudinal HIV care continuum provides greater insight into long-term outcomes and exposes disparities not evident with traditional cross-sectional care continua.

Keywords: HIV; care continuum; continuous retention; disparity; viral suppression.

Figure 1.

Variations in patterns of retention and viral suppression (VS). Patient-years are 12-month follow-up periods for each patient after clinic enrollment. Attended clinic visit, Viral suppression, viral load (VL) > 200 copies/mL. Patient A, Continuous Retention and VS at 12, 24, and 36 months. Patient B, Retention at 12 months and continuous VS at 12, 24, and 36 months. Patient C, No continuous retention because not retained during initial 12 months. Continuous VS at 12 and 24 months. Patient D, Retained at 12 months and never with continuous VS. In cross-section would be retained in year 1 and 3 and virally suppressed in year 3. Abbreviation: Q, quarter within each patient year.

Figure 2.

Longitudinal retention (solid columns) and viral suppression (VS) (striped columns) at 12 months, 24 months, and 36 months. Anytime rates are retention and VS during any single 12-month cross-section. *statistically significant decline (P < .0001) compared with initial 12-month rates and anytime rates. ¥statistically significant decline (P < .0001) compared with 24-month rates. Abbreviation: IDP, Infectious Disease Program.

Figure 3.

Prevalent viral suppression (VS) at the end of 36 months (left Y-axis) by continuous retention (CR) or no continuous retention (No CR). The adjusted prevalence ratio is plotted on the right Y-axis. Abbreviation: IDP, Infectious Disease Program.

Figure 4.

Retention by race over time. There is no difference between the groups at 12 months but by 24 and 36 months, Blacks have significantly lower rates of retention. The interaction between race and time is significant (P = .014) for retention as a longitudinal outcome.