Smoking may trigger early menopause
The earlier a woman stops smoking, the more protected she is from early menopause.
Women who smoke are more likely to enter menopause at a younger age, according to the results of study conducted by Norwegian researchers.
There is a clear association between cigarette smoking and early menopause (defined as occurring before age 45), according to Thea F. Mikkelsen, and colleagues at the University of Oslo.
“Our main finding was that current, active smoking is related to early menopause, and smoking cessation prior to menopausal age seems to protect against early menopause,” they wrote in BMC Public Health.
Additionally, “the earlier a woman stops smoking, the more protection she derives with respect to an early onset of menopause,” they wrote.
The findings were derived from a cross-sectional, population-based study of 2,123 postmenopausal women. Each participant was born in 1940 or 1941 and also participated in the Oslo Health Study.
Mikkelsen, a medical student at the university, and colleagues investigated the association between early menopause and current, past active and passive smoking. To determine smoking status, the researchers questioned each participant on topics such as whether or not they currently smoke, formerly smoked or never smoked; the number of cigarettes smoked per day; what age they started smoking; the number of years since they stopped smoking; how many days spent in a room where people smoked and the number of household members that smoke.
From those data, they determined that 24.2% of women were active smokers, 28.7% were former smokers and 35.2% were passive smokers at baseline.
Findings showed that current smokers had a higher association with early menopause (OR=1.59; 95% CI, 1.11-2.28). Women who stopped smoking more than 10 years before they entered menopause had a decreased risk for early menopause (OR=0.13; 95% CI, 0.05-0.33). Women who smoked the most cigarettes per day and had been smoking the longest had a nearly twofold increase in risk for entering menopause at an early age (OR=1.93; 95% CI, 1.12-3.30).
These data suggest a possible dose–response relationship between smoking and early menopause, according to the researchers.
Other associated factors
The researchers also investigated the association between coffee and alcohol consumption and early menopause.
“Passive smoking and alcohol or coffee consumption were not significantly associated with early onset of menopause,” they wrote.
Certain lifestyle factors previously thought to be associated with early menopause were found to be negatively associated, such as high education level (OR=0.50; 95% CI, 0.34-0.72) and high school participation (OR=0.60; 95% CI, 0.39-0.98). – by Katie Kalvaitis
For more information:
- Mikkelsen TF, Graff-Iversen S, Sundby J, Bjertness E. Early menopause, association with tobacco smoking, coffee consumption and other lifestyle factors: a cross-sectional study. BMC Public Health. 2007;7:149. doi:10:1186/2458-7-149.