Higher khat use was associated with current cigarette smoking (aOR 21.21, 95% = 7.19, 62.51), high levels of common mental disorder symptoms (aOR 1.84, 95% CI = 1.01, 3.36), alcohol use disorders (aOR 2.16, 95% CI = 1.10, 4.21), having CD4 count of ≤200 cells/mm3 (aOR 3.56, 95% CI 1.60, 7.50) and missing ART medication (aOR 4.20, 95% CI = 1.80, 5.75). The gene discussed is CD4; the disease is mental disorder.