Prevalence of dementia in Greece: the Hellenic Longitudinal Investigation in Aging and Diet (HELIAD)

Abstract

Comparisons of prevalence rates across geographic regions may elucidate potential protective and risk factors related to dementia, with implications for public health. Data regarding prevalence rates in southern Europe are limited; in Greece they are also outdated and suffer from several methodological shortcomings. We collected data through a population-representative epidemiological study (Hellenic Longitudinal Investigation in Aging and Diet) in order to estimate the prevalence of dementia and its subtypes in Greece. Our sample consisted of 1867 older adults (>64 years old; 41.3% men) in two locations in Greece, who received a full neurological and neuropsychological evaluation. Of these, 5.0% met diagnostic criteria for dementia (based on consensus diagnostic meetings). Among those with dementia, 75.3% (n=67) had a primary diagnosis of Alzheimer’s dementia (AD) (3.7% of total sample), 9.0% (n=8) vascular dementia, 9.0% (n=8) Parkinson’s dementia (PD) or Lewy Body Dementia (LBD), 1.1% (n=1) Frontotemporal dementia, 2.2% (n=2) alcohol related dementia, and 3.4% (n=3) dementia of other types. In the AD group, 90.3% had probable and 9.7% possible AD. In 58% of the AD group no other diagnoses contributed to the dementia; the remainder of AD participants (42%) had coexisting additional diagnoses contributing to cognitive dysfunction, including vascular dementia (4.3%), LBD (2.2%), PD, stroke and traumatic brain injury with loss of consciousness (each 1.1%), depression (17.2%), anxiety (8.6%) and a history of alcoholism (6.5%). The prevalence of dementia and its subtypes in Greece is similar or at the lower range of that reported in many other developed countries and globally.