This article is more than 5 years old. Information may no longer be current.
Higher levels of leptin associated with lower risk for Alzheimer’s disease, dementia
Click Here to Manage Email Alerts
People with higher levels of leptin, a protein hormone produced by fat cells and involved in the regulation of appetite, may have an associated reduced incidence of Alzheimer’s disease and dementia.
Researchers for a newly published study examined the relationship between measurements of plasma leptin concentration and incidence of dementia and Alzheimer’s disease. Researchers measured plasma leptin concentrations in 785 adults without dementia (mean age, 79 years; 62% women). All were participants in the original Framingham Heart Study at the 22nd examination cycle (1990-1994).
A subsample of 198 dementia-free survivors underwent volumetric brain MRI between 1999 and 2005, more than seven years after leptin was measured. Two measures of brain aging were assessed: total cerebral brain volume and temporal horn volume; both are markers of early Alzheimer’s disease pathology and subsequent dementia risk. The researchers conducted follow-up for new cases of dementia and Alzheimer’s disease until December 2007.
During a median follow-up of 8.3 years, 111 participants developed dementia and 89 of them were diagnosed with Alzheimer’s disease.
The researchers found that higher leptin levels were associated with a lower incidence of all-cause dementia and Alzheimer’s disease. The incidence of dementia decreased gradually across increasing levels of leptin: a person with a baseline leptin level in the lowest quartile group had a 25% risk for developing Alzheimer’s disease after 12 years of follow-up, whereas the corresponding risk for a person in the top quartile group was only 6%.
Higher leptin levels were also associated with higher total cerebral brain volume. Lower temporal horn volume was not significantly related to leptin levels.
These data reflect recent findings that suggest leptin improves memory function in animals via direct effects on the hippocampus and add to the evidence that leptin may have a variety of functions within the central nervous system, according to the researchers.
“If our findings are confirmed by others, leptin levels in older adults may serve as one of several possible biomarkers for healthy brain aging and, more importantly, may open new pathways for possible preventive and therapeutic intervention,” researchers wrote. “Further exploration of the molecular and cellular basis for the observed association may expand our understanding of the pathophysiology underlying brain aging and the development of Alzheimer’s disease.”
Lieb W. JAMA. 2009;302:2565-2572.
This interesting paper shows in a prospective study that leptin levels are inversely related with the risk of developing dementia and Alzheimer's disease with an average 8.3-year follow-up in a group of elderly people from the Framingham Heart Study cohort. This opens an intriguing new vista onto this troublesome problem for the elderly.
- George A. Bray, MD
Endocrine Today Editorial
Board member