Oral Infections and Cytokine Levels in Patients with Alzheimer's Disease and Mild Cognitive Impairment Compared with Controls.
Oral infections are prevalent in the adult population. Their impact includes the implication as a risk factor for Alzheimer's disease (AD), altering its progression. One of the potential mechanisms involves immune mediators such as circulating cytokines.



The goal of the present study was to investigate the prevalence of oral infections and blood levels of IL-1β, TNF-α, and IL-6 in patients with AD, mild cognitive impairment (MCI), and controls.



Sixty-five elderly were evaluated (25 AD, 19 MCI, and 21 controls) by the following methods: Mini Mental State Exam, Questionnaire of Functional Activities, periodontal and oral evaluation, and blood concentrations of IL-1β, TNF-α and IL-6.



Patients with AD had high serum IL-6 levels (p = 0.029), and patients with periodontitis had high serum TNF-α levels (p = 0.005). There was an association between IL-6 and TNF-α in patients with AD/MCI and periodontitis (p = 0.023).



The increased levels of TNF-α and IL-6 in this study suggests their implication in the overlapping mechanisms between oral infections and AD. Longitudinal studies are necessary for further investigation.
Neurology Department, School of Medicine of the University of São Paulo, Brazil.
José Augusto Ferrari
JA
Cestari
Orofacial Pain Team, Dentistry Division, Hospital das Clinicas, School of Medicine of the University of São Paulo, Brazil.|Federal University of Juiz de Fora, Brazil.
Gisele Maria Campos
GM
Fabri
Laboratory of Medical Investigation in Immunology, School of Medicine of the University of São Paulo, Brazil.
Jorge
J
Kalil
Neurology Department, School of Medicine of the University of São Paulo, Brazil.
Ricardo
R
Nitrini
Geriatric Clinic, Clinical Medicine Department, School of Medicine of the University of São Paulo, Brazil.
Wilson
W
Jacob-Filho
Orofacial Pain Team, Dentistry Division, Hospital das Clinicas, School of Medicine of the University of São Paulo, Brazil.
José Tadeu Tesseroli
JT
de Siqueira
Neurology Department, School of Medicine of the University of São Paulo, Brazil.|Orofacial Pain Team, Dentistry Division, Hospital das Clinicas, School of Medicine of the University of São Paulo, Brazil.|Gerontology, School of Arts, Science and Medicine, University of São Paulo, Brazil.
Silvia Regina D T
SR
Siqueira
D000368:Aged; D000369:Aged, 80 and over; D000544:Alzheimer Disease / Q000097:blood* / Q000150:complications; D016022:Case-Control Studies; D060825:Cognitive Dysfunction; D016207:Cytokines / Q000097:blood; D005260:Female; D006801:Humans; D053583:Interleukin-1beta / Q000097:blood; D015850:Interleukin-6 / Q000097:blood; D008297:Male; D008875:Middle Aged; D010518:Periodontitis / Q000097:blood* / Q000150:complications; D014409:Tumor Necrosis Factor-alpha / Q000097:blood
D016207:Cytokines; D053583:Interleukin-1beta; D015850:Interleukin-6; D014409:Tumor Necrosis Factor-alpha
Alzheimer’s disease; IL-6; TNF-α; inflammation; mild cognitive impairment; oral infection; periodontitis