Comment: Note the weasel words highlighted above - may, suggests. This is the first indication that the study actually found nothing that is considered statistically significant. If there was a proven result, they would be loudly proclaiming it.
During the study, stroke survivors exposed to second hand smoke were also more likely to die from any cause compared to those without second hand smoke exposure.
"Second-hand smoke is a risk to all people, but those with a history of stroke should take extra care to avoid it," said lead author Dr. Michelle Lin of the Johns Hopkins School of Medicine in Baltimore. One in four nonsmokers (58 million people) in the U.S. are still exposed to secondhand smoke, according to the Centers for Disease Control and Prevention.
Comment: There are exactly zero studies that find a causal link between second hand smoke and any of the so called "tobacco related" diseases. Even the WHO study which was supposed to prove once for all the harm of second hand smoke, could find no statistically significant result. Nonetheless they still decided that it had to be an issue and proclaimed it as such when they released the study. There is a good summary of the events here.
"While cigarette smoking has long been known to increase the risk of stroke, less is known about the relationship between secondhand smoke and stroke," Lin said by email.
Comment: The only studies claiming a causal link between smoking and stroke are epidemiological studies which are prone to error. They are based on observational studies, with questionnaires which are easy to manipulate to get any result you want.
To explore the question, the study team analyzed data on nearly 28,000 never-smokers over age 18 who participated in annual National Health and Nutrition Examination Surveys.
Participants were recruited between 1988 and 1994 and again between 1999 and 2012. They were asked, "Does anyone who lives here smoke cigarettes, cigars, or pipes anywhere inside this home?" To gauge the amount of smoke people were exposed to, blood tests for cotinine, a breakdown product of nicotine, were performed on each participant.
Comment: Testing for cotinine as proof of exposure to second hand smoke is disingenuous. Common vegetables such as cauliflower, eggplant tomatoes and potatoes naturally contain nicotine and regular consumption of these vegetables ensures cotinine in the blood stream.
The researchers also looked at other factors that might influence stroke risk or likelihood of secondhand smoke exposure like race, sex, education and income level. The people most likely to be exposed to secondhand smoke at home were black men with high alcohol intake and a history of heart attack who were living in poverty.
Comment: Again, the study is also assuming who has exposure to second hand smoke.
Among survey participants between 1999 and 2012, people exposed to high amounts of secondhand smoke, as measured by blood cotinine, were 46 percent more likely than those exposed to little or no smoke to have a history of past stroke.
Comment: The "46% more likely" number doesn't actually tell us the risk. Assuming the number was correct, if the risk of stroke was 1 in 1 million, then the risk factor increases to around 1 in 500,000. Just stating the number without the background information is disingenuous and designed to mislead.
In the 1988-1994 group, the results were different, and secondhand smoke exposure wasn't linked to increased stroke risk. The study team writes in the journal Stroke that this difference requires further investigation.
Comment: The fact that the first groups results were not linked to increased stroke risk makes a mockery of the study. Rather than publish and claim a link between SHS and stroke, the honest answer would be to accept that the study actually has proven nothing.
Comment: The headline bears NO resemblance to the actual results of the research. Sadly this is all too typical of tobacco research and the subsequent false reporting of its results. Sponsors who fund this sort of research will only accept one result, the one proving harm from tobacco. To ensure future funding, the results must be presented to conform to the required result.
Read more about junk science and Tobacco Control here:
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