A previous meta-analysis found that CHD is linked to an increased risk of dementia. CHD occurs in a wide age range. The longer one has the condition, the more likely they are to have worse health outcomes due to accumulated vascular lesions.
The authors of the current study thus wrote it is reasonable to assume that a younger onset of CHD may accelerate cognitive decline and increase dementia risk. Until now, however, whether a link exists between younger age of CHD diagnosis and dementia risk remains unknown.
To shed more light on this potential link, the researchers analyzed data from the UK Biobank from 432, 667 participants who were followed for an average of 13 years. Among them, 5,876 developed dementia over the study period, 2540 Alzheimer's disease, and 1,220 vascular dementia.
After adjusting for demographic and lifestyle factors, they found that participants with CHD were 36% more likely to develop dementia, 13% more likely to develop Alzheimer's disease, and 78% more likely to develop vascular dementia than those without the condition. They additionally found that those diagnosed with CHD before age 45 were the most vulnerable to developing dementia.
"What surprised us most was the linear relationship between age of coronary heart disease onset and dementia. This shows the huge detrimental influence of premature coronary heart disease on brain health," said Fanfan Zheng, Ph.D., senior study author and researcher in the School of Nursing at the Chinese Academy of Medical Sciences & Peking Union Medical College in Beijing, China, in a press release.
"As more people live longer and are diagnosed with coronary heart disease at a younger age, it's likely there will be a large increase in the number of people living with dementia in years to come. Health care professionals should be aware of individuals diagnosed with coronary heart disease at a young age. The next step is to determine whether modifying cardiovascular risk early in life will promote better brain health later in life," she concluded.
Sources: Science Daily, Journal of the American Heart Association