Poor metabolic health was defined as having three or more of the following conditions: high waist circumference, high triglycerides, high blood pressure, high blood glucose, and low high-density lipoprotein (HDL) cholesterol, sometimes known as ‘good’ cholesterol. This cluster of conditions is commonly known as ‘metabolic syndrome’. Approximately 20-25% of adults globally live with metabolic syndrome, which has been previously associated with an increased risk of developing heart disease, stroke and type 2 diabetes.
The researchers in Nuffield Department of Population Health investigated the association between metabolic syndrome and subsequent risk of developing dementia by analysing data from more than 176,000 participants from the UK Biobank study. The health of each participant was tracked through their medical records over a span of 15 years. All participants were aged 60 or older and free of dementia at the start of the study to ensure that the study consisted of people at risk of developing dementia.
Key findings:
- A total of 73,510 participants (42%) had metabolic syndrome when their data were collected at the start of the study;
- Among those with metabolic syndrome, the most common condition was high blood pressure (96%) followed by high triglycerides (74%), low HDL-cholesterol (72%), high waist circumference (70%), and high blood glucose (50%);
- Of the 176,249 study participants, 5,255 went on to develop dementia over a 15 year period;
- Participants with metabolic syndrome had a 12% increased risk of developing dementia compared with participants who did not have metabolic syndrome;
- Having more metabolic syndrome conditions was linked to a greater risk of developing dementia. For instance, having four or five conditions (of any combination) increased the risk of dementia by 19% and 50%, respectively