The increased health risks associated with smoking are well-documented. Now a new study by researchers from the University of Pennsylvania as published in the journal Menopause indicates that smoking causes menopause up to nine years earlier in white women with specific genetic variations.
Previous research has demonstrated that smoking accelerates menopause by one to two years. According to WebMD, the average age of onset for natural menopause in the United States is 51. Earlier menopause increases the risk of osteoporosis, colon and ovarian cancer, periodontal (gum) disease, tooth loss, and cataract formation, among other health problems.
For the present study, the researchers followed over 400 women between the ages of 35 and 47 who took part in the Penn Ovarian Aging Study for 14 years.
Compared to other groups of women in the study, white women with variations of the genes called CYP3A4*1B and CYP1B1*3 entered menopause up to nine years earlier than average. White women with the gene variations but who did not smoke entered menopause an average of 13.91 years after beginning the study. However, light smokers and heavy smokers entered menopause an average of 11.36 years and 5.09 years, respectively, after the start of the study.
Comments lead lead author Samantha F. Butts, MD, MSCE, assistant professor of Obstetrics and Gynecology at Penn Medicine:
“This study could shed new light on how we think about the reproductive risks of smoking in women. We already know that smoking causes early menopause in women of all races, but these new results show that if you are a white smoker with these specific genetic variants, your risk of entering menopause at any given time increases dramatically.”
The researchers did not find the same relationship among smoking, specific gene variants, and earlier menopause in black women. Notes Dr. Butts, “It is possible that uniform relationships among white and African American women were not found due to other factors associated with race that modify the interaction between smoking and genes.”
The researchers also not that the two gene variations do not cause earlier menopause alone. Instead, the variations increase the risk of earlier menopause among white women who smoke.
Seven percent of the white women in the study had the CYP3A4*1B gene variation while 62 percent had the CYP1B1*3 variation.
Additional research is still needed to investigate the lack of statistically significant relationships between smoking, the gene variants, and early menopause in black women. Conclude the researchers, “It is well known that race affects multiple features of menopause, and this could be another. Further investigation is needed to clarify this question.”
The results of this study offer another reason for women to quit smoking.
Cigarettes, genetic background, and menopausal timing: the presence of single nucleotide polymorphisms in cytochrome P450 genes is associated with increased risk of natural menopause in European-American smokers: http://www.ncbi.nlm.nih.gov/pubmed/24448104
Premature menopause: http://www.webmd.com/menopause/guide/premature-menopause
Smoking causes earlier menopause in some white women: http://www.medicalnewstoday.com/articles/272316.php
Fingers Holding Cigarette: http://www.freeimages.com/photo/1152250