Patients with diabetes in middle age were 77% more likely to develop dementia.
Diabetes, high blood pressure, or smoking can increase a patient’s risk of developing cardiovascular disease. Patients with cardiovascular risks in middle age were observed to have an increased risk of developing dementia later in life.
“The health of your vascular system in midlife is really important to the health of your brain when you are older,” lead researcher Rebecca F. Gottesman, MD, PhD, said during a presentation at the American Stroke Association’s International Stroke conference.
The ongoing study began in 1987, and includes 15,744 individuals living in the United States. The investigators discovered that the risk of dementia increased with age, which is already well-established. Surprisingly, the risk of dementia was seen to increase when heart disease risks were identified at baseline in patients aged 45 to 64, according to the study.
During the study, 1516 individuals developed dementia later in life. The investigators found that the dementia risk was 41% higher among patients who smoked midlife, compared with non-smokers or those who formerly smoked.
The risk of dementia was observed to be 39% higher among individuals with high during middle age, and 31% among patients with pre-hypertension during middle age, compared with individuals with normal blood pressure, according to the study.
Notably, the dementia risk was 77% higher among individuals with diabetes in middle age, compared with individuals without diabetes.
“Diabetes raises the risk almost as much as the most important known genetic risk factor for Alzheimer’s disease,” Dr Gottesman said.
The risk of developing dementia was the highest among individuals who were black; had less than a high school education; were older; carried a gene known to increase Alzheimer’s disease risk; or had high blood pressure, diabetes, or were smokers at baseline, according to the study. However, dementia risk was observed to be 11% lower among women.
In both whites and blacks, smoking and predisposition to Alzheimer’s disease were the strongest factors linked to dementia.
“If you knew you carried the gene increasing Alzheimer’s risk, you would know you were predisposed to dementia, but people don’t necessarily think of heart disease risks in the same way,” Dr Gottesman said. “If you want to protect your brain as you get older, stop smoking, watch your weight, and go to the doctor so diabetes and high blood pressure can be detected and treated.”
Going forward, the team of researchers could evaluate whether modifying risk factors would lead to lower dementia risk over time. If lifestyle modification could reduce the dementia risk, it may present physicians and patients with an effective prevention tactic.
“The benefit is that this is a long-term study and we know a lot about these people,” Dr Gottesman concluded. “Data like these may supplement data from clinical trials that look at the impact of treatment for heart disease risks.”