title: HIV testing and burden of HIV infection in black cancer patients in Johannesburg, South Africa: a cross-sectional study.
abstract: BACKGROUND
  HIV infection is a known risk factor for cancer but little is known about HIV testing patterns and the burden of HIV infection in cancer patients. We did a cross-sectional analysis to identify predictors of prior HIV testing and to quantify the burden of HIV in black cancer patients in Johannesburg, South Africa.
  
  
  METHODS
  The Johannesburg Cancer Case-control Study (JCCCS) recruits newly-diagnosed black cancer patients attending public referral hospitals for oncology and radiation therapy in Johannesburg . All adult cancer patients enrolled into the JCCCS from November 2004 to December 2009 and interviewed on previous HIV testing were included in the analysis. Patients were independently tested for HIV-1 using a single ELISA test . The prevalence of prior HIV testing, of HIV infection and of undiagnosed HIV infection was calculated. Multivariate logistic regression models were fitted to identify factors associated with prior HIV testing.
  
  
  RESULTS
  A total of 5436 cancer patients were tested for HIV of whom 1833[33.7% (95% CI=32.5-35.0)] were HIV-positive. Three-quarters of patients (4092 patients) had ever been tested for HIV. The total prevalence of undiagnosed HIV infection was 11.5% (10.7-12.4) with 34% (32.0-36.3) of the 1833 patients who tested HIV-positive unaware of their infection. Men >49 years [OR 0.49(0.39-0.63)] and those residing in rural areas [OR 0.61(0.39-0.97)] were less likely to have been previously tested for HIV. Men with at least a secondary education [OR 1.79(1.11-2.90)] and those interviewed in recent years [OR 4.13(2.62 - 6.52)] were likely to have prior testing. Women >49 years [OR 0.33(0.27-0.41)] were less likely to have been previously tested for HIV. In women, having children <5 years [OR 2.59(2.04-3.29)], hormonal contraceptive use [OR 1.33(1.09-1.62)], having at least a secondary education [OR:2.08(1.45-2.97)] and recent year of interview [OR 6.04(4.45-8.2)] were independently associated with previous HIV testing.
  
  
  CONCLUSIONS
  In a study of newly diagnosed black cancer patients in Johannesburg, over a third of HIV-positive patients were unaware of their HIV status. In South Africa black cancer patients should be targeted for opt-out HIV testing.
authors.affiliation: NHLS/MRC Cancer Epidemiology Research Group, National Cancer Registry, National Health Laboratory Service, Johannesburg, South Africa. mazvita.sengayi@nhls.ac.za.|Graduate School for Cellular and Biomedical Sciences, University of Bern, Bern, Switzerland. mazvita.sengayi@nhls.ac.za.
authors.forename: Mazvita
authors.initials: M
authors.lastname: Sengayi
authors.affiliation: NHLS/MRC Cancer Epidemiology Research Group, National Cancer Registry, National Health Laboratory Service, Johannesburg, South Africa. chantal.babb@nhls.ac.za.|School of Pathology, Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, South Africa. chantal.babb@nhls.ac.za.
authors.forename: Chantal
authors.initials: C
authors.lastname: Babb
authors.affiliation: Institute of Social and Preventive Medicine (ISPM), University of Bern, Bern, Switzerland. egger@ispm.unibe.ch.|Centre for Infectious Disease Epidemiology and Research (CIDER), School of Public Health and Family Medicine, University of Cape Town, Cape Town, South Africa. egger@ispm.unibe.ch.
authors.forename: Matthias
authors.initials: M
authors.lastname: Egger
authors.affiliation: NHLS/MRC Cancer Epidemiology Research Group, National Cancer Registry, National Health Laboratory Service, Johannesburg, South Africa. margurban@gmail.com.|School of Pathology, Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, South Africa. margurban@gmail.com.
authors.forename: Margaret I
authors.initials: MI
authors.lastname: Urban
mesh_terms: D001294:Attitude to Health; D044383:Black People; D016022:Case-Control Studies; D017281:Cost of Illness; D003430:Cross-Sectional Studies; D005260:Female; D015658:HIV Infections / Q000150:complications / Q000175:diagnosis* / Q000453:epidemiology; D015497:HIV-1; D006801:Humans; D008228:Lymphoma, Non-Hodgkin / Q000453:epidemiology / Q000821:virology*; D008297:Male; D008403:Mass Screening; D008875:Middle Aged; D015995:Prevalence; D012514:Sarcoma, Kaposi / Q000453:epidemiology / Q000821:virology*; D013019:South Africa