NYU’s Pesquisadores Langone Health examined the relationship between neutrophils and lymphocytes, known as NLR. Esse value is easily obtained from a complete blood count. Higher Níveis of this ratio was associated with greater likelihood of developing Alzheimer or related dementia, both in the short and long term.
The work was published on April 3, 2026 in the magazineAlzheimer’s & Dementia. The authors used the oldest available records of patients aged 55 and over, before any diagnosis of dementia.
Estudo analyzed data from two large healthcare systems
The research gathered information from approximately 285,000 patients treated at four NYU Langone hospitals and approximately 85,000 individuals from the Estados Unidos Veterans Health System. The researchers followed the history of these patients after the initial NLR measurement.
In both groups, elevated NLR was consistently associated with increased risk. The analysis considered the median value to define what would be high. Metade of participants was above this line, and the other half below.
The results showed a continuous dose-response relationship. Quanto the higher the NLR, the greater the observed chance of future dementia. The association held for both near-risk and longer follow-up.
- Elevated NLR associated with increased risk in both healthcare systems
- Medição made before any diagnosis of dementia
- Pacientes aged 55 or older at time of initial collection
- Análise used each individual’s first qualified value
- Subgrupos from women and Hispanic patients showed stronger associations
Neutrófilos act as the body’s first line of defense
Neutrófilos are a type of white blood cell that responds quickly to infections and inflammation. Quando the immune system activates, their number can rise and alter the balance with other leukocytes, such as lymphocytes. The NLR captures this dynamic and serves as an accessible marker of systemic inflammation.
Previous Estudos studies in animals have suggested that neutrophils may contribute to damage in blood vessels and brain tissue in Alzheimer disease. Sinais inflammation mediated by these cells appears in the brain of patients. However, the authors highlight that there is still no definitive proof of cause and effect in humans.
The neutrophil has a short lifespan in the blood, which makes in-depth analysis difficult. Therefore, most studies use fresh samples. The researchers plan to combine NLR with brain imaging and cognitive assessments to better understand the role of these cells.
Subgrupos show differences in association with dementia
Mulheres presented a higher risk linked to elevated NLR in both systems analyzed. Pacientes Hispanics also had a stronger association, although it is unclear whether this is due to genetic, social factors, or access to health care.
The authors note that NLR alone does not serve as a definitive predictor. Quando combined with other known risk factors, it may help select people who would benefit from closer monitoring, additional testing, or early interventions.
Systemic Inflamação gains prominence in research on Alzheimer
The study reinforces growing evidence that inflammatory processes outside the brain influence the development of dementia. Neutrophils, when fighting infections, can generate collateral damage in chronic conditions. With aging, the ability to eliminate old neutrophils decreases, which can worsen the condition.
Jaime Ramos-Cejudo, one of the senior authors, coordinates the VIDA laboratory, which investigates vascular and immune dysfunction in aging and Alzheimer disease. The team combines markers of neutrophil activity with PET, diffusion MRI and cognitive tests.
The researchers hope to clarify whether neutrophils merely mark risk or whether they actively participate in progression. Nesse last case, they could become therapeutic targets. Enquanto this, the simple NLR could serve as an initial screening tool.
Equipe and study funding
Tianshe (Mark) He, PhD in data science from NYU Departamento of Psiquiatria Grossman School of Medicine, is the first author. Ele and Ramos-Cejudo also serve in the Veterans Health System Cooperative Studies Program at Boston.
The work was supported by multiple grants from National Institutes of Health, Alzheimer’s Association, BrightFocus Foundation and National Alzheimer’s Coordinating Center. Vários researchers from NYU and the VA Boston participated in the analysis.
