A geographical study on amyotrophic lateral sclerosis in Rio Grande Do Norte, Brazil, from 2005 to 2018

Abstract

Objective: amyotrophic lateral sclerosis (ALS) is a rare and fatal neurodegenerative disorder with variable incidence and prevalence worldwide. However, clinical-epidemiological studies on ALS are scarce in Brazil. Thus, this study investigated whether ALS incidence had uniform spatial distribution in population-based cluster analysis in Rio Grande do Norte state (Brazil), from 2005 to 2018. Methods: new cases of ALS were identified in a database of the ALS multidisciplinary care center of the Onofre Lopes University Hospital in Natal (Rio Grande do Norte, Brazil). Approaches were based on incidence (empirical Bayes estimator and Moran's I analysis) and cluster analyses (Moran scatter plot and spatial correlogram). Results: a total of 177 patients (59% males) participated in the study; the mean age of ALS onset was 57 years. Mean annual incidence of ALS was 0.3769 per 100,000 inhabitants (95% confidence interval of 0.0889), higher in males than in females (0.4516 per 100,000 vs. 0.3044 per 100,000). According to spatial statistics, patients were homogeneously distributed throughout the studied area. Conclusion: a low estimate was observed compared with other populations. Results did not indicate areas of increased risk or significant spatial geographic dependence, suggesting a random ALS incidence in Rio Grande do Norte.

Keywords:

• Amyotrophic lateral sclerosis
• motor neuron disease
• epidemiology
• incidence
• spatial analysis

Acknowledgments

The authors thank patients with ALS from our ambulatory care and Laboratório de Inovação Tecnológica em Saúde/HUOL/UFRN. The authors also thank José Wilton de Queiroz for their valuable contributions to this study. He sadly passed away before the publication of the manuscript.

Author contribution

M.E.T.D.J. was responsible for conceiving the study. All authors participated in data analysis and interpretation and manuscript writing. All authors approved the final version of the manuscript before submission.

Declaration of interest

The authors declare no conflicts of interest.

Data availability statement

Patients from the present study did not agree to share data publicly; therefore, supporting data are not available.

Additional information

Funding

This study was supported by the Brazilian Ministry of Health.