Epidemiology of Huntington's Disease in Latin America: A Systematic Review and Meta-Analysis

Background: Latin America has played a crucial role in advancing our understanding of Huntington's disease (HD). However, previous global reviews include limited data from Latin America. It is possible that English-based medical search engines may not capture all the relevant studies. Methods: We searched databases in Spanish, Portuguese, and English. The names of every country in Latin America in English-based search engines were used to ensure we found any study that had molecular ascertainment and provided general epidemiological information or subpopulation data. Additionally, we contacted experts across the region. Results: The search strategy yielded 791 citations; 24 studies met inclusion criteria, representing 12 of 36 countries. The overall pooled prevalence was 0.64 per 100,000 (prediction interval, 0.06–7.22); for cluster regions, it was 54 per 100,000 (95% CI, 34.79–84.92); for juvenile HD, it was 8.7% (prediction interval, 5.12–14.35), and 5.9% (prediction interval, 2.72–13.42) for late-onset HD. The prevalence was higher for Mexico, Peru, and Brazil. However, there were no significant differences between Central America and the Caribbean versus South America. Conclusion: The prevalence of HD appears to be similar across Latin America. However, we infer that our findings are underestimates, in part because of limited research and underdiagnosis of HD because of limited access to molecular testing and the availability of neurologists and movement disorders specialists. Future research should focus on identifying pathways to improve access to molecular testing and education and understanding differences among different ancestral groups in Latin America.