Clinical and Radiological Markers of Periodontal Status and Risk of Cognitive Decline and Incident Dementia

There is evidence linking tooth loss with dementia; however, similar findings for periodontitis are inconclusive.

We conducted cross-sectional (N = 4046) and longitudinal analyses (N = 2769) on data from the Health 2000 and 2011 surveys for establishing any associations of periodontal health with baseline cognition, 11-year risk of cognitive decline and 15-year risk of incident dementia (N = 4073; study period from 1 September 2000 to 31 December 2015). Periodontal health was assessed via multiple clinical and radiographic markers. Based on periodontal pocket depths (PPDs), we defined periodontitis as moderate or severe. Cognitive tests at baseline and follow-up were administered, and dementia diagnoses until 2015 were retrieved from health registers. Analyses included logistic and Cox proportional regression, accounting for reverse causality.

Cross-sectionally, moderate periodontitis was associated with lower overall cognition (OR = 1.19:1.02-1.40), verbal fluency (OR = 1.16:1.00-1.35) and immediate recall (OR = 1.22:1.04-1.42); PPD with lower overall cognition (OR = 1.22:1.04-1.43) and verbal fluency (OR = 1.18:1.02-1.38); and bleeding on probing (BOP) with verbal fluency (OR = 1.26:1.07-1.48) and immediate recall (OR = 1.22:1.02-1.45). Longitudinally, moderate periodontitis was associated with the risk of decline in immediate recall (OR = 1.29:1.04-1.60) and severe periodontitis with verbal fluency (OR = 1.46:1.01-2.11); PPD with immediate recall (OR = 1.23:1.00-1.53); and BOP with verbal fluency (OR = 1.31:1.05-1.63). Edentulism was associated with multiple cognitive tests (OR range:1.71-1.88). No associations with the risk of incident dementia were observed.

Poor periodontal health may increase the risk of cognitive decline. Future studies into the underlying mechanisms are warranted.