Apolipoprotein E polymorphism and dementia: a hospital-based study from southern India
Srikala Bharath1, Meera Purushottam, Odity Mukherjee
1National Institute of Mental Health and Neurosciences, Hosur Road, Bangalore, India. srikala.bharath@gmail.com
Dementia and Geriatric Cognitive Disorders
|January 22, 2011
Summary
The ApoE4 gene variant is more common in individuals with dementia, including Alzheimer's and vascular dementia, in Southern India. This genetic factor may influence dementia risk but not cognitive decline severity.
Area of Science:
- Genetics
- Neurology
- Epidemiology
Background:
- Dementia is a significant health concern, particularly in aging populations.
- The apolipoprotein E (ApoE) gene, specifically the ApoE4 allele, is a known genetic risk factor for dementia.
- Understanding the prevalence of ApoE gene polymorphisms in diverse populations is crucial for risk assessment and potential interventions.
Purpose of the Study:
- To investigate the association between apolipoprotein E (ApoE) gene polymorphism and dementia in a Southern Indian population.
- To determine if the ApoE4 allele is more prevalent in patients with dementia compared to healthy controls.
Main Methods:
- A case-control study involving 212 patients diagnosed with dementia and 195 matched controls from Southern India.
- Standardized assessments were used for diagnosis according to ICD-10 criteria.
- Genotyping was performed at the apolipoprotein E (ApoE) locus to identify genotypes.
Main Results:
- The ApoE4 allele was significantly more prevalent in individuals with dementia (0.18) compared to controls (0.07).
- This association was particularly strong in the Alzheimer's disease subgroup (0.21 vs. 0.07) and showed a trend in vascular dementia (0.17 vs. 0.07).
- No significant difference in ApoE4 carrier status was observed in other dementia types or between Alzheimer's and vascular dementia groups. Cognitive and functional deficits were not correlated with ApoE4 presence.
Conclusions:
- The study confirms a positive association between ApoE4 polymorphism and dementia risk in Southern India, encompassing both Alzheimer's and vascular dementia subtypes.
- The findings highlight the role of ApoE4 as a genetic risk factor for dementia in this population.
- Further research is needed to explore the influence of ApoE polymorphism on clinical phenotypes and disease progression.
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