While the physical health risks of smoking are well known, a November study revealed that excessive smoking can actually hurt cognitive ability.

Participants in the study who had the most risk for stroke had lower cognition and memory compared to those in a lower quartile. Participants who had high blood pressure were also associated with lower global cognitive ability and low memory scores at the eight year follow up.

The study concluded that smoking was always associated with lower cognitive ability than nonsmokers.

Catharine D. Malmsten, an assistant professor at the Medical College of Wisconsin, said she thinks the study shows that different cardiovascular risk factors can contribute to early cognitive decline.

“I think it is an important thing for people to be aware of, because that might be the thing that could make someone stop smoking,” Malmsten said in an email. “Given that smoking has detrimental effects all over the body, if we can get someone to quit smoking, we can potentially improve their overall health quite a lot.”

Malmsten said there is a lot of evidence associated with worsening cognitive ability.

“It may in part be due to the fact that smoking worsens vascular health, increasing the risk of damage to vessels in the brain, potentially leading to strokes, etc.,” Malmsten said. “Also, it tends to be a habit that is associated with other behaviors that are not as good.”

Malmsten said the cognitive damage that is a result of smoking can be halted if that person stops smoking.

“If damage has already occurred, it is unlikely to completely reverse, but preventing it from getting worse by stopping smoking would help,” Malmsten said.

Daniel C. Potts, a national advocate for persons with dementia and their caregivers through the American Academy of Neurology’s Palatucci Advocacy Leadership Forum, said the results of the study didn’t surprise him.

“It makes perfect sense,” Potts said. “Vascular rick factors, such as HTN, physical inactivity, diabetes, hyperlipidemia, etc., increase one’s risk of dementia and Alzheimer’s disease. It follows that smoking, an accelerator of the atherosclerotic process, would be associated with an increased risk of cognitive impairment.”

Potts said he believes the issue of cognitive regeneration still has to be explored.

“If you look at other vascular risk factors like HTN, mid-life HTN is associated with late-life cognitive decline,” Potts said. “So this makes me feel that damage that vascular risk factors exert is done over a long period of time. I would think the damage would have already been done in a chronic smoker.”

He warned against drawing too many conclusions from the study.

“This is not to say risks could not potentially be lowered with cessation of smoking,” Potts said. “I think this needs further study.”

Potts also said what is bad for the heart and blood vessels is likely also bad for the brain.

Jay Matz, the communications director for the American Heart Association in Milwaukee, said the American Heart Association encourages everyone to stop smoking.

“Eighty percent of cardiovascular disease, including stroke, is preventable,” Matz said. “Smoking is one of the seven heart health factors we have identified that people can focus on to lower their risk of heart disease and stroke.  Smoking damages your entire circulatory system and increases your risk for coronary heart disease, hardened arteries, aneurysm and blood clots.”

Matz said blood clots and hardened arteries increase the risk of heart attacks, strokes and peripheral artery diseases. He said smoking can also raise cholesterol and lung capacity, making physical activity harder.