Non-uptake of highly active antiretroviral therapy among patients with a CD4 count < 350 cells/μL in the UK

Objectives
Current British HIV Association (BHIVA) guidelines recommend that all patients with a CD4 count < 350 cells/ mL are offered highly active antiretroviral therapy (HAART). We identified risk factors for delayed initiation of HAART following a CD4 count < 350 cells/ mL.
Methods
All adults under follow-up in 2008 who had a first confirmed CD4 count < 350 cells/ mL from 2004 to 2008, who had not initiated treatment and who had > 6 months of follow-up were included in the study. Characteristics at the time of the low CD4 cell count and over follow-up were compared to identify factors associated with delayed HAART uptake. Analyses used proportional hazards regression with fixed (sex/ risk group, age, ethnicity, AIDS, baseline CD4 cell count and calendar year) and time-updated (frequency of CD4 cell count measurement, proportion of CD4 counts < 350 cells/ mL, latest CD4 cell count, CD4 percentage and viral load) covariates.
Results
Of 4871 patients with a confirmed low CD4 cell count, 436 (8.9%) remained untreated. In multivariable analyses, those starting HAART were older [ adjusted relative hazard (aRH)/ 10 years 1.15], were more likely to be female heterosexual (aRH 1.13), were more likely to have had AIDS (aRH 1.14), had a greater number of CD4 measurements < 350 cells/ mL (aRH/ additional count 1.18), had a lower CD4 count over follow-up (aRH/ 50 cells/ mL higher 0.57), had a lower CD4 percentage (aRH/ 5% higher 0.90) and had a higher viral load (aRH/ log10 HIV-1 RNA copies/ ml higher 1.06). Injecting drug users (aRH 0.53), women infected with HIV via nonsexual or injecting drug use routes (aRH 0.75) and those of unknown ethnicity (aRH 0.69) were less likely to commence HAART.
Conclusion
A substantial minority of patients with a CD4 count < 350 cells/ mL remain untreated despite its indication.