Smoke's Enduring Legacy: Bridging Early-Life Smoking Exposures and Later-Life Epigenetic Age Acceleration

Area of Science:

• Epigenetics
• Developmental Toxicology
• Public Health

Background:

• Previous research linked early smoking exposure to later adverse health outcomes, primarily through continued smoking.
• It was widely believed that smoking cessation could mitigate these risks to non-smoker levels.
• Emerging evidence indicates childhood smoking may independently and permanently impact health, specifically epigenetic aging.

Purpose of the Study:

• To investigate whether early-life smoking's impact on epigenetic aging aligns with a sensitive periods model (independent early effects) or a cumulative risks model (persistent smoking).
• To determine the independent contribution of early-life smoking exposure to epigenetic age acceleration.

Main Methods:

• Analysis of epigenetic aging markers in relation to early-life smoking exposure.
• Comparison of findings against sensitive periods and cumulative risks models of health effects.

Main Results:

• Findings support both the sensitive periods and cumulative risks models.
• Childhood smoking demonstrates long-lasting effects on epigenetic aging, irrespective of subsequent smoking behavior.
• Early-life smoking exposure is a significant contributor to epigenetic age acceleration in later life.

Conclusions:

• Early-life smoking exposure has persistent, independent negative effects on epigenetic aging.
• While adult smoking cessation remains effective for health risk reduction, it does not fully reverse the aging acceleration caused by childhood exposure.
• Interventions targeting prevention of early-life smoking are crucial for long-term health and mitigating epigenetic aging.