Epidemiologic Evidence and Possible Mechanisms for the Association Between Cigarette Smoking and Injuries. Part 2: Is...

Area of Science:

• Public Health
• Epidemiology
• Injury Prevention

Background:

• Part 1 reviewed epidemiologic evidence and mechanisms linking cigarette smoking to injuries.
• This article explores criteria to establish smoking as a direct cause of injuries.

Purpose of the Study:

• To evaluate the causal relationship between cigarette smoking and injury risk using established criteria.
• To synthesize evidence from military and civilian studies on smoking and injury incidence.

Main Methods:

• Review and analysis of existing epidemiologic evidence, including meta-analyses and multiple observational studies.
• Application of nine criteria to assess causality, considering biological plausibility, dose-response, and cessation effects.

Main Results:

• Smokers exhibit a 1.31 times higher risk of injury compared to nonsmokers, with increased risk correlating with smoking levels.
• Substantial evidence indicates past smokers have a higher subsequent injury risk, with risk decreasing post-cessation.
• The association is consistent across diverse injury types and populations, supported by biological plausibility and other health outcomes.

Conclusions:

• The association between cigarette smoking and injuries meets many criteria for a direct causal relationship.
• Risk-taking behavior is a potential confounding factor, but evidence suggests smoking itself contributes to injury risk.
• Cessation of smoking leads to a reduction in injury risk, particularly for bone health and wound healing.