Tooth loss, periodontal disease, and cognitive decline in the Atherosclerosis Risk in Communities (ARIC) study

ObjectiveThe purpose of this prospective study was to investigate whether poor oral health predicted 8-year cognitive function change in predominantly late middle adults in the Atherosclerosis Risk in Communities (ARIC) study. MethodsParticipants included a subset of ARIC participants aged 52-75years at 1996-1998 from two study sites: Forsyth County NC and Jackson MS. All subjects completed cognitive function assessments both in 1996-1998 and 2004-2006, and the same subjects received a dental examination at the initial visit. Cognitive assessment consisted of delayed word recall (DWR), digit symbol substitution (DSS), and word fluency (WF) tests. In the analysis, cognitive function for 911 dentally screened participants was evaluated, and 558 of 785 dentate participants received comprehensive oral examinations, including periodontal probing. Measures of oral health included dental status, number of teeth, and periodontal disease classified by the biofilm-gingival interface (BGI) index. The generalized estimating equations (GEE) method was used to analyze repeated measures of cognitive scores with adjustment for socio-demographic characteristics and cardiovascular risk factors. ResultsOf 911 study participants, 13.8% were edentulous. About 13% of dentally examined participants had periodontal pockets (4mm) with severe bleeding. At the follow-up visit, DWR and WF scores were lower in edentulous compared to dentate people, whereas other oral health measures were not associated with cognitive function. Mean values declined over time for all three cognitive measures, although poor oral health conditions were not associated with greater degree of decline in cognitive function. ConclusionsIn these late middle-aged adults, complete tooth loss was significantly associated with lower cognitive performance. However, neither edentulism, number of teeth, nor periodontal disease predicted greater subsequent cognitive decline.