As we approach April 2025, there’s a growing concern about why dementia seems to be on the rise. Despite some encouraging trends, such as a drop in age-adjusted dementia prevalence over the past few decades, the overall number of dementia cases is still expected to increase. Let’s break down the reasons behind this rise.
Firstly, the world’s population is aging. Advances in medicine have led to people living longer, which increases the likelihood of developing age-related conditions like dementia. According to the American Heart Association, nearly 56 million people worldwide are living with Alzheimer’s disease and other dementias, with more than 6.9 million of them in the U.S. alone[3].
Another factor is the increase in modifiable risk factors. While nearly half of the risk factors for brain disease are modifiable through lifestyle changes like diet and exercise, rising rates of obesity and diabetes could counteract these efforts[3]. For instance, managing chronic diseases like cardiovascular disease has improved significantly, but these improvements are somewhat offset by the growing prevalence of obesity and diabetes[1].
Additionally, some studies suggest that dementia risk after age 55 might be higher than previously thought. A recent study from New York University found that Americans’ risk of developing dementia after turning 55 is more than double what earlier research had estimated[5]. This could lead to a significant increase in dementia cases in the coming years.
Lastly, while there are encouraging signs that dementia prevalence might not rise as sharply as predicted—thanks to declining age-adjusted rates over the past 40 years—the overall number of cases is still expected to grow due to the aging population[1]. This means that even if the risk per person decreases, the sheer number of older people will drive up the total number of dementia cases.
In summary, while there are positive trends in reducing dementia risk, the aging population and rising modifiable risk factors mean that dementia cases are likely
