Incidence and mortality trends of people living with dementia among 7 million individuals over 10 years in Italy: A retrospective cohort study using administrative linked data

Purpose: We aimed to estimate trends of dementia incidence and to compute and compare all-cause mortality among people living with and without dementia, in a whole regional population, from 2013 to 2023. Methods: Our retrospective population-wide cohort study included 7,030,374 people aged 50 years and older from regional administrative data, living in Lombardy, the most populous Italian region. We computed annual age-standardised dementia incidence estimated rates and age-standardised all-cause mortality estimated rates among people living with and without dementia, both overall and stratified by age and sex. Results: Over the last decade, age-standardised dementia incidence estimated rates have decreased by 52.8 % for women and 53.1 % for males. In contrast, age-standardised all-cause mortality estimated rates among people living with dementia grew by 14.0 % for women and 21.8 % for males. Conversely, during the pandemic, there was a higher excess in mortality estimated rates in the female population living with dementia compared to the male, up to 60 % in older groups aged 80 or older. In the male population without dementia compared to the female, the higher excess was up to 50 % in age groups of 70-74 and 75-79. Conclusions: Our study reported a reduction in dementia incidence and increase in all-cause mortality of people living with dementia over the last decade, indicating that dementia prevalence is declining. Moreover, previously under-investigated gender disparities in mortality estimated rates emerged across different age groups during the pandemic.