Neurologic complications of sickle cell disease in Africa: A systematic review and meta-analysis

OBJECTIVE: To summarize prevalence data on the neurologic complications of sickle cell disease (SCD) in Africa. METHODS: We searched EMBASE, PubMed, and African Index Medicus to identify all relevant articles published from inception to May 31, 2016. Each study was reviewed for methodologic quality. A random-effects model was used to estimate the prevalence of neurologic complications of SCD across studies. RESULTS: Thirty-one studies were included. Methodologic quality was high or moderate in 90% of studies. Stroke, conditional and abnormal cerebral blood flow, seizures, and headache were the complications most frequently reported, with overall prevalence rates of 4.2%, 10.6%, 6.1%, 4.4%, and 18.9%, respectively. Some complications, like silent brain infarcts, peripheral neuropathies, neurocognitive deficits, or moyamoya disease, have been rarely or not studied at all in the African setting. Incidence data were scarce and of poor quality. CONCLUSIONS: The burden of neurologic complications of SCD is important in Africa and most likely underestimated. A better evaluation of this burden requires larger prospective studies using standard up-to-date screening methods. Accessibility to diagnostic tools such as neuroimaging, transcranial Doppler, EEG, and neuropsychological evaluation, as well as to preventive and therapeutic interventions and trained health care providers, should be improved in routine clinical practice.