Seventeen Studies from Seven Nations Conclude the Same about Senior Smoking
It is irrefutable that smoking is detrimental to one’s health and is an established risk factor of premature death. According to studies on middle-aged adults, quitting the habit reduces the risk. German researchers conducted a study focused on individuals 60 or older to determine what benefits smoking cessation would have on their lifespan.
Researchers from the Division of Clinical Epidemiology and Aging Research, German Cancer Research Center (DKFZ), in Heidelberg, Germany published their results in the June 11 edition of the Archives of Internal Medicine.
The researchers conducted a systematic literature review of multiple databases including MEDLINE, EMBASE, and ISI Web of Knowledge. They complemented the data by cross-referencing to identify cohort studies published before July 2011. Pertinent factors of identified studies were independently extracted by two reviewers and the results were summarized by standard methods of meta-analysis.
The researchers identified 17 studies from seven different nations. In all the studies, they found that current smoking was associated with increased all-cause mortality. In addition, the relative mortality compared with never smokers ranged from 1.2 to 3.4 times greater risk of death; the risk was 1.83 times higher in the meta-analysis. A decrease of risk mortality of current smokers with increasing age was observed; however, mortality remained increased up to the highest ages. Furthermore, a dose-response relationship of the amount of smoked cigarettes and premature death was observed. Former smokers likewise had an increased mortality (meta-analysis: 1.34 times greater risk); however, excess mortality compared with never smokers clearly decreased with duration of cessation. Benefits of smoking cessation were evident in all age groups, including subjects 80 years and older.
The authors concluded that smoking remains a strong risk factor for premature mortality also at older age. However, smoking cessation is beneficial to individuals of any age.
In an accompanying editorial, Tai Hing Lamb, MD, from the University of Hong Kong School of Public Health, wrote that the smoking cessation finding is especially valuable. He noted, “Many older smokers misbelieve that they are too old to quit or too old to benefit from quitting. Because of reverse causality and from seeing deaths of old friends who had quit recently, some misbelieve that quitting could be harmful. A simple, direct, strong, and evidence-based warning is needed.”
The study authors note that smoking is one of the major risk factors for multiple chronic diseases, such as cardiovascular diseases and cancer, as well as for mortality from the leading causes of death and consequently also for all-cause mortality. Smoking is one of the 10 leading risk factors for death, and according to estimates of the World Health Organization (WHO), it is responsible for 12% of male deaths and 6% of female deaths in the world. In the 21st Century, a billion deaths due to smoking are expected if no changes in smoking behavior are achieved.
Reference: Archives of Internal Medicine