title: Disease burden of stroke in rural South Africa: an estimate of incidence, mortality and disability adjusted life years.
abstract: BACKGROUND
  In the context of an epidemiologic transition in South Africa, in which cardiovascular disease is increasing, little is known about the stroke burden, particularly morbidity in rural populations. Risk factors for stroke are high, with hypertension prevalence of more than 50%. Accurate, up-to-date information on disease burden is essential in planning health services for stroke management. This study estimates the burden of stroke in rural South Africa using the epidemiological parameters of incidence, mortality and disability adjusted life year (DALY) metric, a time-based measure that incorporates both mortality and morbidity.
  
  
  METHODS
  Data from the Agincourt health and socio-demographic surveillance system was utilised to calculate stroke mortality for the period 2007-2011. Dismod, an incidence-prevalence-mortality model, was used to estimate incidence and duration of disability in Agincourt sub-district and 'mostly rural' municipalities of South Africa. Using these values, burden of disease in years of life lost (YLL), years lived with disability (YLD) and DALYs was calculated for Agincourt sub-district.
  
  
  RESULTS
  Over 5 years, there were an estimated 842 incident cases of stroke in Agincourt sub-district, a crude stroke incidence rate of 244 per 100,000 person years. We estimate that 1,070 DALYs are lost due to stroke yearly. Of this, YLDs contributed 8.7% (3.5 - 10.5%) in sensitivity analysis). Crude stroke mortality was 114 per 100,000 person-years in 2007-11 in Agincourt sub-district. Burden of stroke in entire rural South Africa, a population of some 13,000,000 people, was high, with an estimated 33, 500 strokes occurring in 2011.
  
  
  CONCLUSIONS
  This study provides the first estimates of stroke burden in terms of incidence, and disability in rural South Africa. High YLL and DALYs lost amongst the rural populations demand urgent measures for preventing and mitigating impacts of stroke. Longitudinal surveillance sites provide a platform through which a changing stroke burden can be monitored in rural South Africa.
authors.affiliation: MRC/Wits Rural Public Health and Health Transitions Research Unit (Agincourt), School of Public Health, Faculty of Health Sciences, University of the Witwatersrand, Education Campus, St Andrews Road, Parktown, Johannesburg, South Africa. rmtanya@gmail.com.
authors.forename: Mandy
authors.initials: M
authors.lastname: Maredza
authors.affiliation: World Health Organization, Geneva, Switzerland. bertramm@who.int.
authors.forename: Melanie Y
authors.initials: MY
authors.lastname: Bertram
authors.affiliation: MRC/Wits Rural Public Health and Health Transitions Research Unit (Agincourt), School of Public Health, Faculty of Health Sciences, University of the Witwatersrand, Education Campus, St Andrews Road, Parktown, Johannesburg, South Africa. Stephen.Tollman@wits.ac.za.|Centre for Global Health Research, Umeå University, Umeå, Sweden. Stephen.Tollman@wits.ac.za.|INDEPTH Network, Accra, Ghana. Stephen.Tollman@wits.ac.za.
authors.forename: Stephen M
authors.initials: SM
authors.lastname: Tollman
mesh_terms: D000203:Activities of Daily Living; D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002318:Cardiovascular Diseases / Q000453:epidemiology; D002648:Child; D002675:Child, Preschool; D019468:Disease Management; D005260:Female; D006801:Humans; D006973:Hypertension / Q000453:epidemiology; D015994:Incidence; D007223:Infant; D007231:Infant, Newborn; D008297:Male; D008875:Middle Aged; D015995:Prevalence; D019057:Quality-Adjusted Life Years; D012307:Risk Factors; D012424:Rural Population / Q000706:statistics & numerical data; D013019:South Africa / Q000453:epidemiology; D020521:Stroke / Q000453:epidemiology* / Q000401:mortality / Q000503:physiopathology; D055815:Young Adult