Possible relationship between periodontitis and dementia in a North Indian old age population: a pilot study
Authors: Balwant Rai
S C Anand
Jasdeep Kaur
Journal: Gerodontology (2012)
Discipline: CLINICAL MEDICINE
Keywords: Periodontitis; cognitive impairment; dementia; inflammation; inflammatory mediators
Affiliations: Oral Imaging Center, School of Dentistry, Oral Pathology and Maxillofacial Surgery, Katholieke Universiteit Leuven, Leuven, Belgium. 

Abstract:  Background: Periodontitis and cognitive impairment or dementia is relatively common among older adults. Few cross-sectional studies and some longitudinal studies have attempted to link oral health with dementia diagnosis or disease pathology but none has investigated the role of inflammation as a potential mediator. Objectives: This study was planned to establish a relation of inflammatory mediators between periodontitis and dementia. Materials and methods: Fifty-five patients with severe periodontitis (range 60-69 years), 20 with dementia (10:10 M:F; range 59-69) and 32 healthy controls (range 58-69 years) were selected. The socio-demographic characteristics, physical health, oral health, education status, and medical status were measured. Serum C-reactive protein (CRP), matrix metalloproteinase (MMP)-8, MMP-9, total IGF-I, free IGF-I and TNF-alpha and GCF MMP-8 &amp;MMP-9 were calculated. Results: There was no significant difference between the three groups in the level of education, age, occupation, BMI, CAD, CHF and diabetes except dentate status. After adjusting for age, significant differences were found between patients and controls with respect to gingival inflammation, dental plaque, bleeding on probing and probing pocket depth. Total counts of WBCs, neutrophils, thrombocytic counts and serum CRP, MMP-8, MMP-9, TNF-alpha levels were significantly higher in dementia and periodontitis patients in contrast to healthy controls, while, RBC counts, total IGF-I and Hb levels were lowered in dementia and periodontitis patients in comparison to healthy controls, although higher in dementia as compared to periodontitis patients. Conclusions: This study data suggest a relationship of inflammatory mediators between periodontitis and dementia. Further exploration of this is warranted. 

Retracted: No

PubPeer comments:
 Most passages of this paper look very similar to text from 11 other older papers (by different authors). In the graph below, I have highlighted those passages, using a different color for each of the source papers. It appears as if complete paragraphs were reused, with some minor changes. None of the 11 source papers are listed in the references. Most text was taken from Alvarez A et al. Neurobiology of Aging 28 (2007) 533u2013536 (highlighted in orange) and Johannsen A et al. J Periodont Res 2007; 42: 546u2013552. 2007 (highlighted in turquoise). Could the authors please comment on these textual similarities? , 
 Illustration of the textual similarities: ![file] , 
 Table 2 from this paper bears striking similarities to Table 2 from Johannsen A et al. J Periodont Res 2007; 42: 546u2013552. 2007. Some of the standard deviations are identical, and the legend texts are almost similar to each other. ![file] , 
 Table 1 lists the percentages of subjects (controls, periodontitis, and dementia patients) belonging to certain variables. But the percentages do not appear to make sense. With 20 people in a group, it is not possible to obtain percentages of 41.2, 31.1, or 11.1. Could the authors please explain? ![file] , 
 The legend of Table 3 reads Mean (SD) of total number of peripheral blood; leukocytes, neutrophil counts, total RBC counts, Hb level (g dl) and C-reactive protein plasma levels in pancreatic cancer with periodontitis, periodontitis patients and healthy controls. Could the authors please explain why this text contains the words  pancreatic cancer ? This paper does not study people with pancreatic cancer, so this was very unexpected. ![file] , 
 #5 A possible link for the stray reference to pancreatic cancer could be the first author s 2010 paper about [periodontitis and pancreatic cancer](http: revista.uepb.edu.br index.php pboci article viewFile 814 429). That paper includes one table, but doesn t appear to overlap with the table shown in #5. , 
 The Methods of this paper state:  *Fifty-five matched patients 60u201369 years) who had been referred to our clinic were selected for the study due to their severe periodontitis (at least 6 mm loss of clinical attachment) and were undergoing treatment for this condition. Twenty diagnosed dementia patients (10:10 M:F; range 59u201369) were selected and oral examinations were carried out. The control comprised 32 healthy controls (17:15 F:M; range 58u201369 years), none of whom exhibited clinical signs over 5 mm or any clinical attachment loss.* The age ranges do not seem to match the average age of the three subject groups reported in Table 1, which were 44.12, 45,45, and 44.69 years, respectively. ,