Alcohol and Elevated Risk
In all honesty, I have been dragging my feet ( my fingers?) in commenting on this study. I have written about alcohol and increased breast cancer risk before, and, to a large extent, this feels like more of the same. However, I actually received an email from a blog reader (Thank you, Amy!) asking me to write about it. So, reluctantly, here I go.
The reluctance is due--here is the full disclosure right up front--that I do have a glass of wine or a cocktail every single night, or almost every single night, and don't plan to change that habit. I have all kinds of rationalizations about the positive impact on heart disease and all the other possibly mitigating factors (like going to the gym every morning) and the fact that all of these studies show associations, not causes, and some suggest that the risk is only there for women with specific kinds of breast cancer. It is also true, more full disclosure, that my husband is a medical oncologist, and I really don't think he is trying to kill me when he asks if I want a glass of wine. My choices and behaviors, however, are mine, and you should make your own decisions about this.
Okay, here is the report from the famous Nurses' Health Study that has tracked a cohort of 121,700 female nurses since 1976. We have learned a great deal about a lot of health issues from this study, and Wendy Chen, MD and her colleagues felt this was an excellent source of data re alcohol and breast cancer risk.
Here is a quote from MedPage:
Breast cancer risk increased modestly but significantly in women who reported a history of moderate alcohol consumption, investigators reported, confirming results of previous studies.
Women who averaged three to six drinks a week had a 15% higher risk of invasive breast cancer compared with nondrinkers. The excess risk increased to 50% in women who averaged more than 30 drinks a week.
And here is a quote from an editorial in JAMA:
Are these findings relevant for women of any age with breast cancer? Probably not. Among women with premenopausal breast cancer in the Nurses' Health Study cohort, risk estimates for several categories of alcohol consumption exceed unity but are not statistically significant, and the absolute risk increases are small. Unlike the dose-response relationship observed for postmenopausal breast cancers, there was no clear dose-response for premenopausal breast cancers, and women who reported consumption of 2 to 3 drinks per day had a lower breast cancer risk than those who consumed fewer than 2 drinks per day. However, this should not imply that alcohol use in the early adult years is innocuous vis a vis the risk of breast cancer; rather, if the model of risk proposed by Chen et al is plausible, then early exposure to alcohol in young adulthood would contribute to an increased risk of breast cancer in the postmenopausal period.
And from The New York Times:
But like much of the previous research on alcohol's risk and benefits, the new study wa sobservational and lacked a control group, and it drew from self-reports, which can be unreliable. Nor was it able to determine whether changing one's drinking habits over time - drinking a lot early on, for example, and then stopping at age 50 - made any difference.
In an accompanying editorial, Dr. Steven Narod of the Women's College Research Institute in Toronto pointed out that based on the findings, women who consumed two or more drinks a day would see their 10-year risk of breast cancer climb to 4.1 percent from 2.8 percent. And for women who had one drink a day, it would rise to only 3.5 percent from 2.8 percent.
Dr. Susan Love, a clinical professor of surgery at the David Geffen School of Medicine at the University of California, Los Angeles, said the question for many women remained whether the effect on breast cancer risk of cutting back on alcohol is worth losing out on the reduction in heart disease that comes with moderate drinking. "If you do drink, you have to weigh the risks and benefits," she said. "But obviously if you don't drink and you're worried about breast cancer, don't start."
Are you confused yet? And remember that this study and the comments are directed at breast cancer risk--that is, getting breast cancer in the first place. Those of us who have already had the diagnosis are in a different cohort. Common sense would suggest that there are probably similarities, and a few studies have confirmed that to be the case:
I welcome your comments