- While it is normal for people to experience mild cognitive impairment as we age, severe cognitive decline is not a Healthy part of aging.
- Past research shows that making Healthy lifestyle choices, such as not smoking, can help decrease a person’s risk of developing severe cognitive decline.
- A new study found that quitting smoking during midlife or later can still help in slowing down age-related cognitive decline.
As a person gets older, it is not uncommon for them to experience some mild cognitive impairment that might impact their memory or thinking abilities.
For example, as you age, it may become easier to forget where you placed something, like your car keys. Or, it may be easier to lose your focus than it was before.
What is not normal for an aging brain is to experience
Some conditions associated with severe cognitive decline include Alzheimer’s disease and other types of dementia, Parkinson’s disease, and stroke.
Past research shows that making healthy lifestyle choices, such as not smoking, can help decrease a person’s risk of developing severe cognitive decline.
Now, a new study published in the journal The Lancet Healthy Longevity adds to this body of research by reporting that quitting smoking during midlife or later can still help in slowing down age-related cognitive decline.
For this study, researchers analyzed 18 years of health data from three ongoing studies — the English Longitudinal Study of Ageing (ELSA), the Survey of Health, Ageing and Retirement in Europe (SHARE), and the Health and Retirement Study (HRS) — encompassing study participants from 12 countries, including the United States and United Kingdom.
Study participants included 4,718 adult men and women between the ages of 40-89 who quit smoking, matched to another 4,718 participants who continued to smoke.
“We know that smoking harms heart and lung health but we’re still learning about its effects on other aspects of health, including cognitive function,” Mikaela Bloomberg, PhD, senior research fellow in social epidemiology and social statistics in the Department of Epidemiology and Public Health at University College London, and lead author of this study, told Medical News Today.
“Older adults are the least likely to quit smoking, yet they face the greatest health risks from continued smoking,” Bloomberg continued. “It’s well established that quitting earlier in life can reduce many of the physical health harms of smoking, and emerging evidence suggests similar patterns for cognitive outcomes. We wanted to test whether quitting in mid to later life might still be linked to slower cognitive decline.”
At the study’s conclusion, researchers discovered that the cognitive scores for study participants who had quit smoking lowered much less when compared to those who continued smoking.
For smokers that quit, scientists found they slowed their memory decline rate by about 20% and verbal fluency decline rate by about 50%, when compared to those who did not quit.
“Our findings suggest that people who quit smoking, even later in life, tend to experience slower cognitive decline than those who continue to smoke,” Bloomberg explained. “This is important because middle-aged and older smokers are less likely to try quitting, yet face the greatest health risks. Evidence of a possible link between quitting and slower cognitive decline could provide an additional reason to support cessation efforts in this group.”
“Smoking damages cardiovascular health, including the small blood vessels in the brain, which can in turn harm brain structures involved in cognitive function,” she continued. “It’s also linked to chronic inflammation, which is thought to contribute to cognitive decline and dementia.”
Bloomberg said that next steps for this research would be to examine the biological and vascular mechanisms that might explain the link between smoking cessation and cognitive trajectories, and test whether similar patterns are seen for dementia outcomes.
MNT asked Bloomberg if she believed these research findings might be a potential preventative strategy for Alzheimer’s disease and other types of dementia that are many times linked to cognitive decline.
“Age-related cognitive decline and decline due to diseases such as Alzheimer’s are related but distinct processes,” she responded.
“Factors linked to slower age-related decline may not necessarily influence disease-related decline to the same extent. While our results raise the possibility that quitting smoking could also be associated with a lower risk of dementia, this would require further research to confirm. This is especially important for mid- to late-life quitting, as the brain changes involved in Alzheimer’s disease often begin many years before diagnosis.”
– Mikaela Bloomberg, PhD
MNT had the opportunity to speak with Jimmy Johannes, MD, pulmonologist and critical care medicine specialist at MemorialCare Long Beach Medical Center in Long Beach, CA, who commented that this study gives another compelling reason to stop smoking, even for those who are older.
“Cognitive health is often a priority for our patients and their loved ones, especially if they are already experiencing some cognitive decline,” Johannes, who was not involved in this research, explained. “This study reiterates that stopping smoking may be an important way to slow down cognitive decline.”
“While this study provides another line of evidence associating stopping smoking and slowing down cognitive decline, it is still an observational study and is prone to various confounding variables,” he continued. “Stopping smoking completely can be quite challenging for our patients, especially those who are older. It would be interesting to know if cutting down on smoking or reduction in smoking exposure can also be associated with slowing cognitive decline.”
