Prevalence, demographics and etiologies of early-onset dementia in Brazil: a retrospective cohort
Joao Vitor Mahler Ferreira Oliveira1, Marina Solti1, Leonel Takada2, Sonia Brucki2
1Faculdade de Medicina, Universidade de Sao Paulo, 2Grupo de Neurologia Cognitiva e Comportamental - HCFMUSP
Objective:
To describe clinical features, demographics and causes of early-onset dementia in two quaternary outpatient clinics in Brazil.
Background:
Dementia is a growing concern worldwide and is a major cause of disability and impairment to basic activities of daily living. In Latin America, dementia is a leading cause of disease burden. However, few studies evaluate the prevalence and characteristics of EOD in Latin America.
Design/Methods:
Electronic medical records of consecutive, patients seen at two outpatient clinics in 2021, were retrospectively examined. Inclusion criteria included a diagnosis of dementia according to DSM-V and onset at or before 65 years-old.
Results:
625 EMRs were reviewed. 102 were classified as EOD, yielding a prevalence of 16.3%. 54 (52.9%) were females. Mean age at onset was 56.8 years. Mean years of education was 8.48. Etiologies found were Alzheimer’s (40; 39.2%), Vascular dementia (7; 6.8%), Alzheimer’s and vascular (5; 4.9%), Frontotemporal dementia (12; 11.7%), dementia with parkinsonian features - LBD, PSP, MSA (5; 4.9%), multifactorial (9; 8.8%), others (11; 10.7%), and unknown/under investigation (13; 12.7%). No differences were found when comparing age at onset, age at admission, initial MMSE and schooling years among different causes. Positive first-degree family history of dementia was frequent (36.2%). Genetic causes included mutations in PSEN1, APP and TYROBP.
Conclusions:
Prevalence and proportion of different dementia types matched previously reported cohorts from developed countries (Harvey & Rossor, 2003). Differences were noted when comparing with a previous Brazilian cohort of EOD (Fujihara et al, 2004), mainly a higher prevalence of AD and lower prevalence of vascular dementia. No difference was found when comparing mean schooling years, initial MMSE, age at onset and at admission among different causes of EOD.