However, while the mediating effects of body mass index and combined body mass index/waist circumference were attenuated by additional confounders, including CD4 cell count and duration of HIV infection, we observed that the mediating effects of waist circumference remained statistically significant, accounting for 11 % (coefficient: 1.01, 95 % CI: 0.33 to 2.52) and 9 % (coefficient: 0.68, 95 % CI: 0.26 to 1.89) of the total effects of HAART on systolic blood pressure and diastolic blood pressure, respectively. This evidence concerns the gene CD4 and HIV infectious disease.