If This Doesn’t Make You Quit Smoking, I Give Up!

A study in the Archives of Internal Medicine shows that two packs of cigarettes a day at 40-50 will double your risk of developing Alzheimer’s.  A link between smoking and dementia has been somewhat controversial, and this study, from Finland and Sweden, was intended to resolve the relationship.

Data were obtained from a healthcare system survey on the smoking habits of 21,123 participants.  They were aged between 50 and 60, and they were monitored for Alzheimer’s disease and vascular dementia for the next 24 years.      

A quarter of the participants developed dementia – either Alzheimer’s disease or vascular dementia.  The risk for developing dementia increased as the amount smoked at enrollment increased.  Thus people who smoked more than two packs of cigarettes a day had over twice the risk for dementia during the next 23 years, compared with those who'd never smoked. 

After adjustments for age, gender, education, race, marital status, blood pressure, high cholesterol, BMI, diabetes, heart disease, stroke, and alcohol intake, the likelihoods of a 2-packs-a-day smoker to develop dementia of any kind, Alzheimer’s disease, or vascular dementia, were 2.14, 2.57, and 2.72 respectively, compared with never-smokers.  However, ex-smokers and moderate smokers (less than 10 cigarettes a day) had no increased risk, compared to non-smokers. 

So, if you smoked in your 50s, don’t imagine you’ve got away with it if you’re lungs and cardiovascular system are in fine shape in your 70s.  It’s clear from this study that your brain is also at risk.  The likely mechanism?   Smoking  increases oxidative stress and inflammation, which are believed to raise the risk for Alzheimer’s.  Today’s a good day to quit.