Is Periodontitis a Risk Factor for Cognitive Impairment and Dementia? A Case-Control Study

Background: Dementia is a multi-etiologic syndrome characterized by multiple cognitive deficits but not always by the presence of cognitive impairment. Cognitive impairment is associated with multiple non-modifiable risk factors but few modifiable factors. Epidemiologic studies have shown an association between periodontitis, a potentially modifiable risk factor, and cognitive impairment. The objective of this study is to determine whether clinical periodontitis is associated with the diagnosis of cognitive impairment/dementia after controlling for known risk factors, including age, sex, and education level. Methods: A case-control study was conducted in Granada, Spain, in two groups of dentate individuals aged >50 years: 1) cases with a firm diagnosis of mild cognitive impairment or dementia of any type or severity and 2) controls with no subjective memory loss complaints and a score >30 in the Photo-test cognitive test (screening test for cognitive impairment). Periodontitis was evaluated by measuring tooth loss, plaque and bleeding indexes, probing depths, and clinical attachment loss (AL). Results: The study included 409 dentate adults, 180 with cognitive impairment and 229 without. A moderate and statistically significant association was observed between AL and cognitive impairment after controlling for age, sex, education level, oral hygiene habits, and hyperlipidemia (P = 0.049). No significant association was found between tooth loss and cognitive impairment. Conclusion: Periodontitis appears to be associated with cognitive impairment after controlling for confounders such as age, sex, and education level.