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Reduced frequency of ALS in an ethnically mixed population: a population-based mortality study
T Zaldivar1, J Gutierrez, G Lara
1Institute of Neurology and Neurosurgery, Havana, Cuba.
Neurology
|May 13, 2009
Summary
Amyotrophic lateral sclerosis (ALS) mortality rates in Cuba are similar to Hispanic populations and lower than in Northern Europeans. Mortality from ALS was found to be lowest in the mixed-ancestry population, suggesting a role for ancestry in disease susceptibility.
Area of Science:
- Epidemiology
- Neurology
- Public Health
Background:
- Few population-based epidemiologic studies of Amyotrophic Lateral Sclerosis (ALS) exist for non-European populations.
- Preliminary data suggest lower ALS frequency in Hispanic and African groups compared to European descent.
- Cuba's ethnically diverse population (white, mixed, black) and high standard of healthcare offer a unique setting for ALS research.
Purpose of the Study:
- To determine Amyotrophic Lateral Sclerosis (ALS) mortality rates within the ethnically diverse Cuban population.
- To analyze ALS mortality trends over a six-year period (2001-2006).
- To investigate potential correlations between mortality rates, ethnicity, sex, age, and geographic region.
Main Methods:
- Utilized multiple-cause mortality files from Cuba's Central Statistics office (2001-2006).
- Searched mortality data for codes corresponding to Amyotrophic Lateral Sclerosis (ALS).
- Calculated age-adjusted mortality rates stratified by sex, race/ethnicity, age, and region.
Main Results:
- Identified 432 deaths with an Amyotrophic Lateral Sclerosis (ALS) diagnosis; mean age at death was 63.7 years.
- Observed a slight male predominance (1.1:1).
- The overall age-adjusted ALS mortality rate was 0.83 per 100,000 population; rates were lower in mixed-ancestry (0.55) and black (0.87) populations compared to white (0.93) populations.
Conclusions:
- Amyotrophic Lateral Sclerosis (ALS) mortality in Cuba aligns with rates in U.S. Hispanic populations and is lower than in Northern European populations.
- Mortality from ALS is significantly lower in the mixed-ancestry Cuban population.
- Ancestral origin appears to be a contributing factor in Amyotrophic Lateral Sclerosis (ALS) susceptibility.
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