Purpose: Idiopathic normal pressure hydrocephalus (iNPH) is the leading reversible cause of cognitive impairment and gait disturbance that has similar clinical manifestations and accompanies to major neurodegenerative disorders in older adults. We aimed to investigate whether cerebrospinal fluid (CSF) biomarker for Alzheimer’s disease (AD) may be useful in the differential diagnosis of iNPH. Patients and Methods: Amyloid-beta (Aß) 42 and 40, total tau (t-tau), phosphorylated tau (p-tau) were measured via ELISA in 192 consecutive CSF samples of patients with iNPH (n=80), AD (n=48), frontotemporal dementia (FTD) (n=34), Lewy body diseases (LBDs) (n=30) consisting of Parkinson’s disease dementia and dementia with Lewy bodies. Results: The mean age of the study population was 75.6± 7.7 years, and 54.2% were female. CSF Aβ₄₂ levels were significantly higher, and p-tau and t-tau levels were lower in iNPH patients than in those with AD and LBDs patients. Additionally, iNPH patients had significantly higher levels of t-tau than those with FTD. Age and sex-adjusted multi-nominal regression analysis revealed that the odds of having AD relative to iNPH decreased by 37% when the Aβ₄₂ level increased by one standard deviation (SD), and the odds of having LBDs relative to iNPH decreased by 47%. The odds of having LBDs relative to iNPH increased 76% when the p-tau level increased 1SD. It is 2.5 times more likely for a patient to have LBD relative to NPH and 2.1 times more likely to have AD relative to iNPH when the t-tau value increased 1SD. Conclusion: Our results suggest that levels of CSF Aβ₄₂, p-tau, and t-tau, in particularly decreased t-tau, are of potential value in differentiating iNPH from LBDs and also confirm previous studies reporting t-tau level is lower and Aβ₄₂ level is higher in iNPH than in AD.

Aim: This study aimed to determine the possible interrelationships between sarcopenia and Alzheimer’s disease (AD). Background: Sarcopenia and AD are two common geriatric syndromes; however, the relationship between AD and sarcopenia has not been evaluated in detail so far. Objective: The objective is to evaluate the relationship between AD and sarcopenia. Methods: This cross-sectional study was performed retrospectively on 128 patients with probable AD, with a mean age of 76.56±7.54 years. Comprehensive Geriatric Assessment, including the activities of daily living (ADLs), malnutrition, frailty, mini-mental state examination (MMSE), and orthostatic hypotension was performed. Sarcopenia was defined according to the revised EWGSOP-2 criteria. Results: The frequency of probable sarcopenia and definitive sarcopenia was 54.7% and 18.7%, respectively. AD patients with probable sarcopenia had lower MMSE and ADLs scores and were frailer. Clinical dementia rating (CDR) score, MMSE, and basic and instrumental ADLs were independently related to probable sarcopenia in the patients (p=0.003, p<0.001, p=0.001, and p=0.001, respectively). The prevalence of probable sarcopenia in those with CDR 2 was higher than in those with CDR 0.5 and 1 (p=0.002). Conclusions: Our findings suggest that probable sarcopenia seems to be related to worse MMSE and ADLs scores and frailty in patients with AD and seems to be related to the severity of AD. Considering adverse health outcomes and the burden of sarcopenia on the patients and their caregivers, optimal care and treatment of sarcopenia in patients with AD are of great importance.