- Older adults with levels of hemoglobin outside the reference range, either low or high, had elevated dementia risk.
Why this matters
- Increasing prevalence of dementia, coupled with lack of interventions to prevent and treat it.
- During mean 12.1-year follow-up:
- 12.4% of cohort developed dementia of any type.
- 9.7% specifically developed Alzheimer’s disease.
- Hemoglobin levels showed U-shaped association with dementia risk (P=.005).
- When middle quintile of levels was comparator, risk was similarly elevated for:
- Lowest quintile (HR, 1.29; 95% CI, 1.09-1.52).
- Highest quintile (HR, 1.20; 95% CI, 1.00-1.44).
- Anemia, present in 6.1% of cohort, conferred elevated risks for:
- Dementia of any type (HR, 1.34; 95% CI, 1.11-1.62).
- Alzheimer’s disease (HR, 1.41; 95% CI, 1.15-1.74).
- Cerebral microbleeds (HR, 1.45; 95% CI, 1.09-1.93).
- Higher hemoglobin levels correlated with lower cerebral perfusion (P<.0001>
- Population-based cohort study of 12,305 middle-aged and older adults (mean age, 64.6 years) without dementia (Rotterdam Study).
- Main outcomes: dementia, Alzheimer’s disease, measures on brain MRI.
- Funding: Netherlands Cardiovascular Research Initiative; Erasmus Medical Centre; Erasmus University Rotterdam; others.
- Residual and unmeasured confounding.
- MRI performed in only a subset.
- Unknown generalizability.