Although Cognitive Tests Still in Normal Limits, Tau and Amyloid-? is high in APOE?4 Carriers in Cases with Subjective Memory Complaints

Title : Although Cognitive Tests Still in Normal Limits, Tau and Amyloid-? is high in APOE?4 Carriers in Cases with Subjective Memory Complaints

Abstract:

Background: Subjective memory complaints (SMC) are often detected in the elderly. APOE?4 genotype has been identified as the most important risk factor for late onset Alzheimer Disease (AD). We aimed to evaluate temporal change of Tau and Amyloid Beta (Aβ) in SMC with APOE-ε4 carriers (C) and non-carriers (NC) based on cognitive tests. 

Method: In order to find cognitive changes from baseline to 1 year follow up of AD patients, Assessment Scale (ADAS)-13 scores were evaluated according to APOE-?4 status in SMC cases from Alzheimer’s Disease Neuroimaging Initiative  (ADNI) data. SMC cases were divided into two groups as NC and C according to APOE-ε4 genotypes. Phosphorylated Tau (PTau) and Aβ were compared among the groups.   

Results: Total 87 SMC cases  (n:33 C, 54 NC,  female/male: %51/49,  mean age of NC group was 72± 5.5 and C group was 70±5.2 years) were enrolled to the study from ADNI. PTau levels were 28.5± 12,35.8± 18, 20.1± 6, 20.8± 7 pg/ml in C and NC group at baseline and 24 months later, respectively.  In C group, PTau levels were significantly high since the begining. Aβ levels were 961± 378, 799± 274, 1180± 347, 1097.8± 355 pg/ml in C and NC group at baseline and 24 months later respectively. In C group, Aβ levels were significantly low since the beginning.  There were no significant difference between two groups  of ADAS-13 scores at the  beginning or 24 months later.

Conclusion: APOE?4 carriage may be associated with cognitive impairment in SMC as well as AD patients despite the accumulation of Tau and Aβ
where cognitive dysfunction cannot be measured by objective tests.  Long-term follow-up studies are needed.

Biography:

Nilgun Cinar graduated from the Cumhuriyet University School of Medicine. She  worked as practician doctor in Sinop and Ankara between 1996 and 2001. She completed her residency in neurology in Eskisehir Osmangazi University School of Medicine. She worked in different instituitons, including  Sanlıurfa Siverek State Hospital and Aksaray Training and Research Hospital Neurology Services between 2006-2008. She became Assistant Professor in 2009 and associate Professor in 2013 at Maltepe University School of Medicine. She published many articles to both national and international journals. Dr. Cinar generally works  in multidisciplinary areas, including cognitive neurology, stroke, headache, electrophysiology and movement disorders. She is an active member of cognitive neurology and quality of life working study group of Turkish Neurological Society.  She currently works as Assoociate Proffessor of Neurology  in Maltepe  University, Deparment of Neurology.