Strand BH, et al. - In this investigation, researchers estimated life expectancy (LE) in early-onset [defined as mild cognitive impairment {MCI} or dementia diagnosis before age 65] dementia or early MCI patients, and loss in expectation of life (LEL) for these groups. Comparisons have been made with the Norwegian general population and a subgroup of late-onset dementia patients. Using flexible parametric survival models, LE and LEL were anticipated. The study sample consisted of newly diagnosed cases (n = 4,906), aged 50–90 years at the time of diagnosis, in the Norwegian register of persons assessed for cognitive symptoms (NorCog) between 2009 and 2017, and patients were followed up for mortality or censorship until January 2018. According to findings, early-onset MCI was connected with significant life years lost (5–6 years), but the loss for those with early-onset dementia was especially pronounced, decreasing the anticipated lifespan by 2 decades.