Evaluating methods for the prevention of cognitive decline and dementia

The number of people with dementia is increasing worldwide, and there is still no treatment that can cure the condition. This thesis investigated risk factors and potential interventions to better understand and possibly slow down cognitive decline and dementia. Low levels of blood pressure, BMI, and non-HDL cholesterol in later life were strongly associated with a higher risk of dementia, particularly when these occurred in combination. Multidomain lifestyle interventions showed no effect on cognitive decline, except possibly among individuals who already had impaired cognitive function. Certain antihypertensive medications—especially calcium channel blockers and angiotensin II receptor blockers—were associated with a lower risk of dementia. Variability in blood pressure over the years was linked to an increased risk only at very old age, making a causal relationship less likely. Finally, no clinically relevant effect was found for immunotherapy targeting beta-amyloid in Alzheimer’s disease. These findings highlight the complexity of dementia prevention and the importance of targeted follow-up studies.