| Mild cognitive impairment (MCI) represents a state of high risk for dementia but is heterogeneous in its course. To date, the trajectories reflecting distinct developmental courses of cognition among patients with MCI, and their association with readily available clinical information, have not been well defined. Study 1 sought to identify the developmental trajectory of groups with distinct cognitive change patterns among a cohort of MCI patients. Study 2 was conducted to identify individual items/subtests of the Mini-Mental State Examination (MMSE) and demographic variables at baseline that predicted the identified trajectories of cognitive change from Study 1. One hundred and eighty-seven MCI patients were evaluated serially with the MMSE for up to 3.5 years. Five trajectories were identified and labeled based on their baseline MMSE score and course: 29-stable (6.4%); 27-stable (53.9%); 25-slow-decline (23.8%); 24-slow-decline (11.6%); 25-rapid-decline (4.2%). In multivariate logistic regression analysis, a model was established to dissociate patients with stable vs. declining trajectories. An equation derived from this model that included age, delayed recall, constructional praxis, attention, and orientation to time and floor predicted future cognitive decline with good accuracy (79.9%) and specificity (86.4%), and moderate sensitivity (67.2%). The identification of varying trajectories of cognitive change and predictors of cognitive decline from easily obtained baseline clinical information can help target at-risk groups for early interventions aimed at delaying the onset of dementia. |
