Incidence rate of Kaposi sarcoma in HIV-infected patients on antiretroviral therapy in Southern Africa: a prospective multicohort study.
BACKGROUND
The risk of Kaposi sarcoma (KS) among HIV-infected persons on antiretroviral therapy (ART) is not well defined in resource-limited settings. We studied KS incidence rates and associated risk factors in children and adults on ART in Southern Africa.


METHODS
We included patient data of 6 ART programs in Botswana, South Africa, Zambia, and Zimbabwe. We estimated KS incidence rates in patients on ART measuring time from 30 days after ART initiation to KS diagnosis, last follow-up visit, or death. We assessed risk factors (age, sex, calendar year, WHO stage, tuberculosis, and CD4 counts) using Cox models.


RESULTS
We analyzed data from 173,245 patients (61% female, 8% children aged <16 years) who started ART between 2004 and 2010. Five hundred and sixty-four incident cases were diagnosed during 343,927 person-years (pys). The overall KS incidence rate was 164/100,000 pys [95% confidence interval (CI): 151 to 178]. The incidence rate was highest 30-90 days after ART initiation (413/100,000 pys; 95% CI: 342 to 497) and declined thereafter [86/100,000 pys (95% CI: 71 to 105), >2 years after ART initiation]. Male sex [adjusted hazard ratio (HR): 1.34; 95% CI: 1.12 to 1.61], low current CD4 counts (≥500 versus <50 cells/μL, adjusted HR: 0.36; 95% CI: 0.23 to 0.55), and age (5-9 years versus 30-39 years, adjusted HR: 0.20; 95% CI: 0.05 to 0.79) were relevant risk factors for developing KS.


CONCLUSIONS
Despite ART, KS risk in HIV-infected persons in Southern Africa remains high. Early HIV testing and maintaining high CD4 counts is needed to further reduce KS-related morbidity and mortality.
*Institute of Social and Preventive Medicine (ISPM), University of Bern, Bern, Switzerland; †Health Economics and Epidemiology Research Office, Department of Internal Medicine, School of Clinical Medicine, Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, South Africa; ‡Division of Infectious Diseases, Department of Medicine, University of Stellenbosch and Tygerberg Academic Hospital, Cape Town, South Africa; §Department of Pediatrics and Child Health, University of Stellenbosch and Tygerberg Academic Hospital, Cape Town, South Africa; ‖Khayelitsha ART Program, Medecins Sans Frontieres, Cape Town, South Africa; ¶Independent Surgery, Gaborone, Botswana; #Newlands Clinic, Harare, Zimbabwe; **Centre for Infectious Disease Research in Zambia (CIDRZ), Lusaka, Zambia; ††Boston University School of Medicine, Section of Geriatrics, Boston, MA, USA; and ‡‡Centre for Infectious Disease Epidemiology and Research (CIDER), University of Cape Town, Cape Town, South Africa.
Eliane
E
Rohner
Fabio
F
Valeri
Mhairi
M
Maskew
Hans
H
Prozesky
Helena
H
Rabie
Daniela
D
Garone
Diana
D
Dickinson
Cleophas
C
Chimbetete
Priscilla
P
Lumano-Mulenga
Izukanji
I
Sikazwe
Natascha
N
Wyss
Kerri M
KM
Clough-Gorr
Matthias
M
Egger
Benjamin H
BH
Chi
Julia
J
Bohlius
D000328:Adult; D000353:Africa, Southern / Q000453:epidemiology; D044966:Anti-Retroviral Agents / Q000627:therapeutic use*; D018791:CD4 Lymphocyte Count; D015331:Cohort Studies; D042241:Early Diagnosis; D005260:Female; D015658:HIV Infections / Q000150:complications* / Q000188:drug therapy* / Q000276:immunology; D006801:Humans; D015994:Incidence; D008297:Male; D011446:Prospective Studies; D012307:Risk Factors; D012514:Sarcoma, Kaposi / Q000453:epidemiology*; D016019:Survival Analysis
D044966:Anti-Retroviral Agents