The aim of this study was to identify dementia trajectories and their associated predictors among elderly Taiwanese people over a 14-year period using a nationwide representative longitudinal study. This retrospective cohort study was performed using the National Health Insurance Research Database. Group-based trajectory modeling (GBTM) was used to distinguish the specific trajectory groups of incident dementia during 2000-2013. All 42,407 patients were classified by GBTM to identify the trajectory of incident dementia, which included high- (n = 11,637, 29.0%), moderate- (n = 19,036, 44.9%), and low-incidence (n = 11,734, 26.1%) groups. Those diagnosed with hypertension (adjusted odds ratio [aOR] = 1.43; 95% confidence interval [CI] = 1.35-1.52), stroke (aOR = 1.45, 95% CI = 1.31-1.60), coronary heart disease (aOR = 1.29, 95% CI = 1.19-1.39), heart failure (aOR = 1.62, 95% CI = 1.36-1.93), and chronic obstructive pulmonary disease (aOR = 1.10, 95% CI = 1.02-1.18) at baseline revealed tendencies to be classified into high-incidence groups in dementia risk. The results from a 14-year longitudinal study identified three distinct trajectories of incident dementia among elderly Taiwanese people: patients with cardiovascular disease risk factors and cardiovascular disease events tended to be classified into high-incidence dementia groups. Early detection and management of these associated risk factors in the elderly may prevent or delay the deterioration of cognitive decline.
Keywords: dementia; group-based trajectory model; longitudinal; predictors; trajectory.