Suicide and Alzheimer's pathology in the elderly: a case-control study

Area of Science:

• Neuropathology
• Geriatrics
• Psychiatry

Background:

• Age is the primary risk factor for Alzheimer's disease (AD) pathology.
• Elderly individuals face an elevated risk of suicide.
• Limited research exists on the connection between AD pathology and suicide in the elderly.

Purpose of the Study:

• To investigate the prevalence of Alzheimer's disease neuropathology in elderly individuals who died by suicide.
• To determine if specific AD-related brain changes are more common in suicide cases compared to controls.

Main Methods:

• A case-control study design was employed.
• Cases included 28 individuals over 60 who completed suicide.
• Controls comprised 56 age- and gender-matched individuals who died naturally.
• Neuropathologic examination of hippocampal sections included modified Braak staging and assessment of AD hallmarks (neurofibrillary tangles, amyloid deposition, Lewy bodies).

Main Results:

• Suicide cases exhibited significantly higher modified Braak scores compared to controls (p =.0028).
• While not an independent predictor, neurofibrillary tangle counts in CA1 were markedly higher in suicide cases.
• A substantial skew in tangle distribution was observed in cases versus controls.

Conclusions:

• Severe Alzheimer's disease pathology is disproportionately found in elderly individuals who die by suicide.
• These findings highlight a potential association between advanced AD pathology and completed suicide in older populations.