October 30th, 2012
The Research Agrees: Smoking Is Really Bad for You
Larry Husten, PHD
Four new studies offer powerful evidence of the dangers of smoking and the health benefits of quitting or not being exposed to secondhand smoke.
Smoking in the U.K. — Between 1996 amd 2001, the Million Women Study started following more than one million women aged 50 to 65 years of age. In a report published in the Lancet, trial investigators, including renowned epidemiologist Richard Peto, found that 12-year mortality was significantly higher in women with a history of smoking compared with women who never smoked (rate ratio 2.76, CI 2.71-2.81). Smokers, the authors calculated, lose 10 years of life. The good news is that stopping smoking before the age of 40 reduces the excess mortality by 90%.
Smoking in Japan — The Life Span Study, published in BMJ, was started in 1950 and has followed more than 65,000 men and women in Hiroshima and Nagasaki, Japan. The results were consistent with the Million Women Study in the U.K.: the rate ratio for mortality was more than doubled for smokers compared with nonsmokers both for men (2.21, CI 1.97-2.48) and for women (2.61, CI 1.98-3.44). The investigators also reported that stopping smoking before age 35 eliminated almost all of the risk associated with smoking.
Smoke-free legislation meta-analysis — Smoking is not just a personal decision that has individual health effects. A new meta-analysis published in Circulation found that smoke-free legislation results in immediate reductions in hospital admissions or deaths for coronary events (RR 0.848, CI 0.816-0.881), other heart disease (RR 0.610, CI 0.440-0.847), cerebrovascular accidents (RR 0.840, CI 0.753-0.936), and respiratory disease (RR 0.760, CI 0.682-0.846). The authors, Crystal Tan and Stanton Glatz, also report that the biggest reductions in events were associated with the most stringent smoke-free laws.
Smoke-free legislation in Minnesota — Here’s one more study to lend support to the above meta-analysis. In a paper published in the Archives of Internal Medicine, Richard Hurt and colleagues analyzed data before and after the implementation of a smoke-free law in Olmsted County, Minnesota. They found a significant, 33% reduction in the incidence of MI (from 150.8 to 100.7 per 100,000 people) and a trend in the reduction of sudden cardiac death by 17% (from 109.1 to 92.0 per 100,000 people). In an accompanying commentary, Sara Kalkhoran and Pamela Ling write that as “the evidence base documenting the positive health outcomes” of smoke-free legislation grows, “we should prioritize the enforcement of smoke-free policies, eliminating loopholes in existing policies as well as encouraging expansion of smoke-free policies to include multiunit housing, motor vehicles, casinos, and outdoor locations. Exposure to SHS [secondhand smoke] should not be a condition of employment, and all workers, including those of lower income and those in the service and hospitality industries, should have equal protection from SHS exposure.”