CD4 and pulmonary emphysema: [22] They also demonstrate accelerated attrition of telomeres in replicative cells such as certain leukocytes and progenitor cells. [23], [24] In experimental models, reduction in telomere length has been shown to increase the risk of emphysema in the presence of chronic cigarette smoke exposure. [25] It is also notable that direct HIV variables such as current CD4 count and plasma viral load had very little impact in predicting the occurrence of emphysema or bronchiolitis most likely because these patients were treated with ART and had a good clinical and virologic response.