ALCOHOL CAUSES 4% OF CANCER DEATHS 

Alcohol use accounted for approximately 3.5% of all cancer deaths in the United States, according to a study that used data from 2009 and was published online February 14 in theAmerican Journal of Public Health.

Alcohol caused about 19,500 cancer deaths, with each alcohol-attributable death resulting in about 18 years of potential life lost, report the study authors, led by David Nelson, MD, MPH, from the National Cancer Institute in Bethesda, Maryland.

This is the first comprehensive study of alcohol-attributable cancer deaths in the United States since 1978, according to the authors. The previous study found the related death rate to be about 3%, so the problem could be growing.

"Our findings demonstrate there has been little, if any, progress in reducing alcohol-attributable cancer deaths in the United States," Dr. Nelson and colleagues write.

The more alcohol a person drinks, the greater the risk for related cancer death, they found. But even low consumption levels are associated with risk. "In sum, there is no apparent threshold when it comes to alcohol and cancer risk," the authors note.

Specifically, an estimated one half to two thirds of all alcohol-attributable cancer deaths occurred in people who consumed an average of 40 g of alcohol per day or more (at least 3 drinks). However, approximately one third occurred in people who consumed 20 g of alcohol per day or less (fewer than 1.5 drinks).

The majority of alcohol-attributable cancer deaths in women were from breast cancer and in men were from upper airway and esophageal cancers.

Dr. Nelson and colleagues based their estimates of the number of alcohol-attributable cancer deaths in the United States on meta-analyses published since 2000 (for the relative risks of alcohol-related deaths and related cancer types) and on adult alcohol-consumption data (from the 2009 Alcohol Epidemiologic Data System, the 2009 Behavioral Risk Factor Surveillance System, and the 2009–2010 National Alcohol Survey).

Their study received widespread media coverage in the United States last week. In his blog, Howard LeWine, MD, from Harvard Medical School and Harvard Health Publications in Boston, Massachusetts,reminded readers that the message about alcohol and cancer needs to be balanced with the cardiovascular benefits of moderate alcohol consumption.

Dr. LeWine cited a recent meta-analysis of studies of alcohol use and cardiovascular health (BMJ. 2011;342:d671). More than 2 million men and women were followed for an average of 11 years. That meta-analysis found that moderate drinkers had lower risks for coronary artery disease, death from any heart or blood vessel disease, and death from any cause, including cancer, than nondrinkers.

However, Dr. Nelson and colleagues do not put much stock in such studies. "Studies on the effects of moderate drinking have serious limitations related to confounding, selection bias, and other factors," they write.

"For most alcohol users, therefore, reducing alcohol consumption would likely improve their health in many ways in addition to reducing cancer risk," they add.

The problem of alcohol-related cancer deaths is worse in Europe, where per capita alcohol consumption is higher than it is in the United States, the authors point out. For example, a recent European study found that alcohol accounted for 10% of total cancer incidence in men and 3% in women (BMJ. 2011;342:d1584).

Reducing alcohol consumption is "an important and underemphasized cancer prevention strategy," write Dr. Nelson and colleagues.

In fact, a recent study (Sci Transl Med. 2012;4:127rv4) places alcohol as the eighth most common cause of cancer in the United States, after smoking (33% of all cancers); overweight/obesity (20%); and diet, lack of exercise, occupation, viruses, and family history (5% each), Dr. Nelson told Medscape Medical News.

7 Cancers Analyzed

The study authors calculated the population-attributable fractions of alcohol-attributable cancer mortality and the years of potential life lost.

The fractions are necessary, they point out, because only a portion of deaths from specific types of cancer can be attributed to alcohol. They limited their analyses to the 7 types of cancers (oral cavity and pharynx, larynx, esophagus, liver, colon, rectum, and female breast) that have been "considered causally associated with alcohol use" by expert bodies such as International Agency for Research on Cancer.

They used 2 different methods to calculate their estimates to increase the likelihood of accuracy.

Overall estimates of deaths were close, ranging from 18,178 to 21,284 (average, 19,503). This amounted to 3.2% to 3.7% of all cancer deaths in 2009.

Cancers of the oral cavity and pharynx, larynx, and esophagus accounted for 3790 to 8395 of alcohol-attributable deaths in men (53% to 71%), and breast cancer accounted for 4730 to 7310 of alcohol-attributable deaths in women (56% to 66%).

This study was supported in part by the National Institute on Alcohol Abuse and Alcoholism. The authors have disclosed no relevant financial relationships.

Am J Public Health. Published online February 14, 2013. Abstract