Dear Doctors: I read that there's a big new study that lists some of the most common risk factors for developing dementia at an early age. I would like to know more about it. How was it done, and what are the risk factors that were identified?
Dear Reader: We believe you're referring to a study that appeared in the December issue of JAMA Neurology, a monthly medical journal published by the American Medical Association. It was conducted by a team of researchers from universities in England and the Netherlands. They were interested in learning whether people younger than 65 who experienced symptoms of dementia shared certain risk factors in common. They also wanted to separate genetic factors from health issues, behaviors and environmental influences associated with young-onset dementia. The goal was to identify any factors that might be modified, thus lessening someone's risk.
The study analyzed a four-year span of genetic, lifestyle and health information from more than 356,000 women and men participating in UK Biobank, a large-scale health database. Each person was under the age of 65 and had not been diagnosed with any cognitive issues. When researchers analyzed the health data, they identified 39 risk factors linked to the onset of dementia. Screening for the most common risk factors narrowed the list to 15.
Not surprisingly, genetics was found to play a role. Specifically, individuals with two copies of the APOE gene, which studies show is linked to Alzheimer's risk, had an increased likelihood of developing young-onset dementia. Additional risk factors over which participants had no control was having a lower socioeconomic status and a lower level of formal education. But then came the good news. Quite a few of the 15 risk factors for young-onset dementia identified by the researchers are behaviors and situations that can be changed for the better.
Social isolation was associated with a higher risk of cognitive decline in both men and women. So was poor hearing, which can contribute to social isolation. The study adds to the importance of working to build and maintain social connections throughout our lives. It's also a reminder to get your hearing checked and to use a hearing aid when needed.
Additional risk factors included having diabetes, having had a stroke, vitamin D deficiency, poor grip strength, heart disease and alcohol abuse. When it came to diabetes, the link to developing dementia was stronger in men than in women, perhaps because men have more microvascular complications than women. Abstinence from alcohol also turned up in the risk factors column. The researchers suspect this is due to diseases or medications that required those participants to stop drinking.
What's striking about this list is it doesn't include any real surprises. The lifestyle-related risk factors for developing young-onset dementia mirror those associated with poor general health. The takeaway here is that when you're taking care of your heart, managing blood sugar, interacting with other people, eating well and exercising regularly, you are not only maintaining your physical health and well-being, but you're also taking important steps to safeguard your cognition.
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