UCLA

HIV/AIDS population is known has higher risk of many malignant tumors, but cancer spectrum among HIV/AIDS population in China has not been reported, and risk factors of Kaposi Sarcoma (KS) among HIV-infected Chinese population remains unknown. This dissertation study describes the spectrum of malignancies among HIV/AIDS population in China, 2008-2011, and explores associated factors of KS both in the national HIV/AIDS cohort and in a hospital-based case-control study among HIV-infected Uyghur people in Xinjiang, China.

In part I, we used cohort data of national HIV/AIDS surveillance and information system during 2008-2011 to calculate standardized incidence rates (to China census 2010) and standardized incidence ratios (with China tumor registry 2008) of all reported cancers. Totally 3819 cancer reports were found from 399,451 subjects with followed-ups between 2008 and 2011. Higher risk was found in both AIDS-defining cancers (KS, lymphomas and cervical cancer) and non-AIDS-defining cancers (lung, liver, stomach, etc.) Comparing with western countries, HIV/AIDS population in China had lower risk of Kaposi Sarcoma, lymphomas, similar risk of female cervical cancer but higher risk of non-AIDS-defining cancers including lung, liver, and stomach cancers.

In part II, we analyzed risk factor of KS in the national HIV/AIDS cohort using Cox proportional hazard model. Being male (Hazard Ratio, HR 1.68, 95%CI 1.13-2.40), Uyghur ethnic (HR 5.30, 95%CI 3.68-7.64), HIV transmission route (heterosexual vs. intravenous drug use, HR 1.75 95%CI 1.12-2.74), lower CD4 cell count at HIV diagnose (comparing with subjects with CD4 ≥ 350/μL at HIV diagnosis, HR for CD4<200/μL was 4.07, and 3.27 for CD4 200~349/μL). Antiretroviral treatment was found a protective factor of KS, with HR 0.39 95%CI 0.27-0.56. Sub-set cohort of Uyghur results were similar.

In part III, we established a hospital-based matched case-control study among HIV-infected Uyghur people and got 39 KS cases and 93 controls. Using conditional logistic regression models, we found HIV transmission route (heterosexual vs. intravenous drug use, Odds Ratio, OR 0.37, 95%CI 0.14-1.00) was risk factor of KS while antiretroviral treatment was protective (OR 0.13, 95%CI 0.03-0.72). Bayesian analysis with priors from Part II and sensitivity analysis found posterior ORs of HIV transmission routes and ART were consistent with national HIV-infected Uyghur cohort.