Making sense of cerebral palsy prevalence in low-income countries
Authors: Bernard Dan, Nigel Paneth
Journal: The Lancet Global Health (2017)

Much of what we know about cerebral palsy—including its effect on motor functioning, quality of life, families, and society; the importance of associated disabilities; the effectiveness of management strategies; and even fundamental epidemiological features, such as prevalence and risk factors—is derived from observations made in high-income countries (HICs). Yet, the burden of cerebral palsy is thought by many to be greater in low-income countries (LICs), for which little information is available. The paucity of studies of cerebral palsy in LICs makes reports from these settings valuable, particularly if they are large, population-based efforts enrolling samples unbiased by clinical ascertainment. In The Lancet Global Health, Angelina Kakooza-Mwesige and colleagues1Kakooza-Mwesige A Andrews C Peterson S Mangen FW Eliasson AC Forssberg H Prevalence of cerebral palsy in Uganda: a population-based study.Lancet Glob Health. 2017; (published online Oct 25.)http://dx.doi.org/10.1016/S2214-109X(17)30374-1Summary Full Text Full Text PDF PubMed Scopus (80) Google Scholar investigate cerebral palsy prevalence in a mostly rural district in Uganda using a three-stage survey adapted from an epilepsy survey in Kenya.2Ngugi AK Bottomley C Chengo E et al.The validation of a three-stage screening methodology for detecting active convulsive epilepsy in population-based studies in health and demographic surveillance systems.Emerg Themes Epidemiol. 2012; 9: 8Crossref PubMed Scopus (38) Google Scholar The research team first screens for motor impairment and delayed development using two questions from the Ten Question tool developed by Durkin and colleagues.3Durkin MS Wang W Shrout PE et al.Evaluating a ten questions screen for childhood disability: reliability and internal structure in different cultures.J Clin Epidemiol. 1995; 48: 657-666Summary Full Text PDF PubMed Scopus (69) Google Scholar The second stage, which, similar to the first, uses trained local fieldworkers who are experts in the cultural and linguistic context of the population,4Dan B Strengthening the foundations of Africa's neurology services.Lancet Neurol. 2009; 8: 227Summary Full Text Full Text PDF PubMed Scopus (1) Google Scholar focuses more specifically on cerebral palsy with questions developed by the Surveillance of Cerebral Palsy in Europe team. The final diagnosis is assigned by a specialist team in the third stage. This approach is a model of community survey work; it allowed the investigators to locate cerebral palsy in time and space, to measure and describe its burden, and to begin to understand its causes. The team surveyed 31 756 children aged 2–17 years and found that 86 children met the criteria for cerebral palsy, giving a crude prevalence of 2·7 (95% CI 2·2–3·3) per 1000 children, which increased to 2·9 (2·4–3·6) per 1000 children after adjusting for attrition. With inclusion of 11 children who were missed by the three-stage screen but detected during triangulation, crude prevalence would have increased to 3·1 per 1000 children. This figure is at the high end of prevalence estimates for HICs, which are usually 2·0–2·5 per 1000 children, although a higher prevalence than found in Uganda has been reported in the USA5Kirby RS Wingate MS Van Naarden Braun K et al.Prevalence and functioning of children with cerebral palsy in four areas of the United States in 2006: a report from the Autism and Developmental Disabilities Monitoring Network.Res Dev Disabil. 2011; 32: 462-469Crossref PubMed Scopus (148) Google Scholar and Korea.6Park MS Kim SJ Chung CY Kwon DG Choi IH Lee KM Prevalence and lifetime healthcare cost of cerebral palsy in South Korea.Health Policy. 2011; 100: 234-238Crossref PubMed Scopus (36) Google Scholar Comparisons must be made with caution. Kakooza-Mwesige and colleagues1Kakooza-Mwesige A Andrews C Peterson S Mangen FW Eliasson AC Forssberg H Prevalence of cerebral palsy in Uganda: a population-based study.Lancet Glob Health. 2017; (published online Oct 25.)http://dx.doi.org/10.1016/S2214-109X(17)30374-1Summary Full Text Full Text PDF PubMed Scopus (80) Google Scholar directly examined a population, whereas cerebral palsy registers and surveillance systems in Europe, Australia, and North America obtain data from medical records.7Goldsmith S McIntyre S Smithers-Sheedy H et al.An international survey of cerebral palsy registers and surveillance systems.Dev Med Child Neurol. 2016; 58: 11-17Crossref PubMed Scopus (36) Google Scholar Screening procedures, such as those used by the authors, might yield a higher cerebral palsy prevalence in Europe than estimates based on medical records. However, the screening programme was a prevalence survey. Children with cerebral palsy who died, and who might have been detected in medical records in HICs, could not be enumerated. The authors suggested that mortality was probably high in children with severe cerebral palsy, leading to a deficit of severely affected cases among older children. Thus, the true cumulative incidence of cerebral palsy in Uganda must be higher than recorded in this study. The community in which this survey took place was the Iganga-Mayuge Health and Demographic Surveillance Site, initiated in 2004 by Ugandan and Swedish investigators as a resource for training, research, and evidence-based decision making. The programme focuses on maternal and newborn health, injuries, health services research, and surveillance for malaria and pneumonia in children younger than 5 years. Such programmes are remarkable assets in any country and an example of collaboration between two countries with different resource levels. The epidemiological features of cerebral palsy in Uganda, and perhaps many LICs, are distinctly different from the features in HICs. Preterm birth is a major risk factor of cerebral palsy in HICs, accounting for a third to a half of all cases. However, in the Ugandan survey, only 2% of children with cerebral palsy had been born preterm. This proportion is almost certainly an indicator of high mortality among preterm infants in Uganda. Postnatal causes, particularly the sequelae of cerebral malaria and other infections of the central nervous system, accounted for 25% of cerebral palsy cases in the study; in HICs, this proportion rarely exceeds 10%. Cerebral palsy has many causes, and identification of causes—such as cerebral malaria in this study—is the first step in development of prevention strategies. Identification of the cause can lead to development of prevention strategies. The high prevalence of postnatal cerebral palsy in this population highlights the importance of prevention of cerebral malaria in children; 90% of cerebral malaria is in children younger than 5 years, and the disorder leads to epilepsy, cerebral palsy, and other neurodevelopmental problems in many survivors.8Postels DG Birbeck GL Cerebral malaria.Handb Clin Neurol. 2013; 114: 91-102Crossref PubMed Scopus (38) Google Scholar Thus, serious infections during infancy and early childhood in sub-Saharan Africa cause lifelong disability as well as kill. Studies in LICs have shown promising new approaches for the control of newborn infections,9Panigrahi P Parida S Nanda NC et al.A randomized synbiotic trial to prevent sepsis among infants in rural India.Nature. 2017; 548: 407-412Crossref PubMed Scopus (299) Google Scholar and progress in diagnosis and treatment of cerebral malaria in young children.10Birbeck GL Beare N Lewallen S et al.Identification of malaria retinopathy improves the specificity of the clinical diagnosis of cerebral malaria: findings from a prospective cohort study.Am J Trop Med Hyg. 2010; 82: 231-234Crossref PubMed Scopus (54) Google Scholar Kakooza-Mwesige and colleagues show the important role of infection in disability and provide suggestions for public health action. We declare no competing interests. Prevalence of cerebral palsy in Uganda: a population-based studyCerebral palsy prevalence was higher in rural Uganda than in high-income countries (HICs), where prevalence is about 1·8–2·3 cases per 1000 children. Children younger than 8 years were more likely to have severe cerebral palsy than older children. Fewer older children than younger children with cerebral palsy suggested a high mortality in severely affected children. The small number of preterm-born children probably resulted from low preterm survival. About five times more children with post-neonatal cerebral palsy in Uganda than in HICs suggested that cerebral malaria and seizures were prevalent risk factors in this population. Full-Text PDF Open Access