Recent research published by Dutch scientists indicates that smokers have a significantly higher risk of developing early-onset dementia and other types of dementia compared to those who have successfully quit smoking and those who have never smoked.
According to a Reuters report on September 3, Dr. Monique Breteler and her colleagues at the Erasmus Medical Center in Rotterdam found that smokers over the age of 55 are 50% more likely to develop symptoms of dementia than their non-smoking peers of the same age.
In their paper, published in the journal *Neurology*, Breteler and her colleagues stated that they had conducted a follow-up study on nearly 7,000 people aged 55 and older for an average of 7 years. During this period, a total of 706 of the study participants developed various types of dementia.
It is already known that a gene called APOE4 (also known as apolipoprotein E4) can increase a person's risk of dementia. The study found that for those who already have this gene, smoking does not affect their future risk of developing early-onset dementia. However, for those without the gene who continue to smoke, their risk of developing early-onset dementia in the future increases by 70%.
"Smoking can lead to stroke, which in turn can damage the brain and eventually lead to dementia," Breteler said. "Smoking increases the risk of cerebrovascular disease (stroke), and this is inextricably linked to dementia."
He also said: "Another mechanism for the onset of dementia symptoms is oxidative stress, which damages cells in the body's blood vessels and leads to arteriosclerosis. Compared to non-smokers, oxidative stress is often more pronounced in smokers, and similarly, elevated levels of oxidative stress have been found in patients with early-onset dementia."
The process of oxidative stress is actually very similar to rusting; it is a chemical reaction that damages the body's DNA.