In the multivariable analysis, participants with multiple prior ART regimens (aOR 4.63, [95% CI 2.36, 9.09], p < 0.01), treatment interruptions (aOR 4.33, [95% CI 1.72,10.87], p < 0.01), and low CD4 count at diagnosis (aOR 2.36, [95% CI 1.07,5.22], p = 0.03) were associated with higher odds of PV, as shown in Table 3. This evidence concerns the gene CD4 and acquired polycythemia vera.