Can the systemic immune-inflammatory index be a new indicator for the diagnosis and follow-up of alzheimer's disease?

ABSTRACT
Background: Alzheimer's disease (AD) is a chronic neurodegenerative disease whose prevalence continues to increase in the 
elderly population. It has been shown that the neutrophil/lymphocyte ratio (NLR), is increased in AD compared to the normal 
population. However, there is no study in the literature regarding the role of systemic immune-inflammatory index (SII), which 
is calculated according to the formula of peripheral platelet count X neutrophil count/lymphocyte count, in AD. Therefore, our 
aim in this study was to reveal the role of SII in the diagnosis and follow-up of AD and to determine the relationship of this 
value with severity, duration of disease and drug use by comparing it with NLR.
Materials and Methods: Our retrospective study consisted of 94 gender and age matched healthy volunteers and 102 patients 
who applied to our clinic were diagnosed with AD.
Results: There was no difference between the patient and control groups in terms of age, gender, platelet and neutrophil counts, 
and SII values. While lymphocyte count was lower in-patient group; NLR and CRP detected higher (p=0.001, p=0.001, 
p=0.001, respectively). While SII increased as both disease duration and severity elevated; no statistically significant correlation 
was found between NLR and the severity and duration of the disease and drug use.
Conclusions: Based on the data of our study, we can suggest that inflammatory process increases in AD. However, the 
relationship of this inflammatory process with the severity and duration of the disease and drug use is still unknown.