Sickle cell trait in São Tomé e Príncipe: a population-based prevalence study in women of reproductive age

BMC Public Health. 2024 Mar 19;24(1):850. doi: 10.1186/s12889-024-17761-1.

Abstract

Background: Sickle Cell Disorder is Africa's most prevalent genetic disease. Yet, it remains a neglected condition, with high mortality under-five, and a lack of population-based studies in the region. This is the first of its kind in São Tomé e Príncipe, aiming to estimate the prevalence of sickle cell trait and other haemoglobin variants in women of reproductive age and its associated factors.

Methods: We conducted a cluster survey in 35 neighbourhoods. Haemoglobin was assessed through point-of-care capillary electrophoresis or high-performance liquid chromatography, and sociodemographic data through questionnaires. The weighted prevalence of sickle cell trait (HbAS) and HbC carriers was estimated with a 95% confidence interval (95% CI). We calculated weighted prevalence ratios (95% CI) through robust Poisson regression for its association with age and individual and collective genetic heritage.

Findings: The prevalence of sickle cell trait in women of reproductive age in São Tomé e Príncipe (n = 376) was 13.45% (95% CI: 9.05-19.00). The prevalence of HbC carriers was 8.00% (95% CI: 4.71-12.00). Older age and speaking Forro or Angolar were positively associated with having sickle cell trait.

Interpretation: The prevalence of sickle cell trait in São Tomé e Príncipe ranks high in the West African region. The country should follow international guidelines, implementing newborn screening and comprehensive healthcare management.

Keywords: Cluster sampling; Genetics; Haemoglobinopathies; Sickle cell disease; Sub-saharian Africa.

MeSH terms

  • Anemia, Sickle Cell* / epidemiology
  • Anemia, Sickle Cell* / genetics
  • Cross-Sectional Studies
  • Female
  • Hemoglobins
  • Humans
  • Infant, Newborn
  • Prevalence
  • Sickle Cell Trait* / epidemiology
  • Sickle Cell Trait* / genetics

Substances

  • Hemoglobins