Table 4.

Longitudinal HIV-1B analysis: predictors of switch of co-receptor tropism.

Variable	Median [IQR]		HR [95% CI]	aHR [95% CI]
	Remains CCR5-tropic (NSI virus)	Switches to CXCR4-tropic (SI visus)
Age (years) at seroconversion	36.6 [32.8–42.4]	36.8 [30.2–40.0]	0.976(ns) [0.920–1.035]	0.962(ns) [0.909–1.019]
HIV-RNA load (10log copies/mL) at 1 year after seroconversion	4.4 [3.9–4.8]	4.5 [4.2–5.0]	1.572(ns) [0.891–2.775]	1.521(ns) [0.859–2.692]
CD4+ T-cell count (cells/µL) at 1 year after seroconversion	610 [490–823]	570 [408–773]	0.959(ns) [0.885–1.040]	1.009(ns) [0.920–1.106]
%HLA-DR+ in CD4+ T-cells at 1 year after seroconversion	4.5 [3.5–6.8]	6.0 [4.8–10.6]	1.174** [1.062–1.298]	1.186** [1.065–1.321]
%HLA-DR+ CD38+ in CD4+ T-cells at 1 year after seroconversion	3.0 [2.1–4.2]	3.3 [2.7–6.4]	1.210** [1.070–1.369]	–

Four patients were excluded from the analysis who had evidence of a switch before the first year post seroconvcersion, 16 out of 78 samples were X4 tropic in this analysis.

%HLA-DR+CD38+ CD4+ T-cells was not incorporated in the multivariable analysis due to observed collinearity with %HLA-DR+ CD4 T-cells (Spearman’s ρ = 0.94).

(a)HR (adjusted) Hazard ratio, SI syncytium-inducing, NSI non-SI, 95% CI 95% confidence interval.

(ns) = p ≥ 0.05, * = p < 0.05, ** = p ≥ 0.01.