Modifiable risk factors
Researchers also calculated how changes in risk factors might affect dementia prevalence. They found that improvements in global education access would reduce dementia prevalence by an estimated 6.2 million cases worldwide by 2050. However, that decrease would be offset by expected increases in obesity, high blood sugar, and smoking, which investigators estimate will result in an additional 6.8 million dementia cases.
The projections are based on expected trends in population aging, population growth, and risk factor trajectories, but “projections could change if effective interventions for modifiable risk factors are developed and deployed,” Ms. Nichols said.
In 2020, the Lancet Commission on Dementia Prevention, Intervention, and Care issued an update of its 2017 report, identifying 12 modifiable risk factors that could delay or prevent 40% of dementia cases. The risk factors were low education, hypertension, hearing impairment, smoking, midlife obesity, depression, physical inactivity, diabetes, social isolation, excessive alcohol consumption, head injury, and air pollution.
“Countries, including the U.S., should look to develop effective interventions for modifiable risk factors, but also should invest in the resources needed to support those with dementia and their caregivers,” Ms. Nichols said. She added that additional support for research and resources to develop therapeutic interventions is also warranted.
Oversimplifying mechanisms?
In an accompanying commentary, Michaël Schwarzinger, MD, and Carole Dufouil, PhD, of Bordeaux (France) University Hospital, noted that the authors’ efforts to build on GBD 2019 oversimplify the underlying mechanisms that cause dementia. The authors “provide somehow apocalyptic projections that do not factor in advisable changes in lifestyle over the lifetime,” they wrote.
“There is a considerable and urgent need to reinforce a public health approach towards dementia to better inform the people and decision-makers about the appropriate means to delay or avoid these dire projections,” the editorialists added.
The study was funded by the Bill and Melinda Gates Foundation and Gates Ventures. Ms. Nichols and the editorialists disclosed no relevant financial relationships.
A version of this article first appeared on Medscape.com.