Association between type 2 diabetes and amyotrophic lateral sclerosis

Area of Science:

• Genetics and Epidemiology
• Neurodegenerative Diseases
• Metabolic Disorders

Background:

• Type 2 diabetes (T2D) and amyotrophic lateral sclerosis (ALS) show consistent epidemiological association.
• The causal relationship between T2D and ALS remains unclear.
• Understanding this link is crucial for potential therapeutic strategies.

Purpose of the Study:

• To estimate the unconfounded, causal association between T2D and ALS risk.
• To investigate this association in both European and East Asian ancestries.
• To apply a robust Mendelian randomization approach.

Main Methods:

• Utilized a two-sample Mendelian randomization (MR) approach.
• Employed genetic variants strongly associated with T2D.
• Analyzed data from large European (20,806 ALS cases, 59,804 controls) and East Asian (1234 ALS cases, 2850 controls) cohorts.
• Assessed potential horizontal pleiotropy using MR-Egger regression.

Main Results:

• Genetically predicted T2D was associated with significantly lower odds of ALS in European populations (OR=0.96, 95% CI 0.92-0.996).
• A similar inverse association was observed in East Asian populations (OR=0.83, 95% CI 0.70-0.992).
• MR-Egger regression indicated minimal influence from horizontal pleiotropy.

Conclusions:

• Genetically predicted Type 2 diabetes is causally associated with a reduced risk of amyotrophic lateral sclerosis.
• This inverse relationship holds true across European and East Asian ancestries.
• Further research is needed to elucidate the molecular mechanisms and therapeutic implications of this association.