Escalating alcohol use among American women has driven up overall binge drinking rates

The overall rates of binge drinking in the US have increased in recent years due to sharply rising rates of drinking among women, according to a new study that also finds stark disparities in alcohol use between counties in the same state.

Binge drinking among women rose by 17.5% compared with a rise of 4.9% among men between 2005 and 2012.

New research conducted by the Institute for Health Metrics and Evaluation (IHME) at the University of Washington, and published in the American Journal of Public Health, is the first to track trends in alcohol use at county level, according to the authors.

Heavy drinking is defined by the Centers for Disease Control and Prevention (CDC) as exceeding an average over the past month of one drink per day for women or two drinks per day for men. 

The CDC define binge drinking as consuming four drinks or more for women in a single occasion, or five drinks or more for men.

While binge drinking is associated with higher risk for serious bodily harm - injuries, alcohol poisoning and acute organ damage - heavy drinking is associated more with long-term conditions including liver cirrhosis and cardiovascular disease.

The new report finds that heavy drinking in the US has risen by 17.2% since 2005 and binge drinking has increased by 8.9% over the same period.

In 2012, 8.2% of Americans were defined as heavy drinkers and 18.3% were considered to be binge drinkers. The lowest levels of binge drinking (5.9% of residents) were found in Madison County, Idaho, and the highest (36% of residents) were in Menominee, Wisconsin. Hancock County, Tennessee, had the lowest levels of heavy drinking (2.4%), with Esmeralda County, Nevada, reportedly hosting the greatest proportion of heavy drinkers (22.4%).

Although rates of heavy drinking and binge drinking have risen between 2005 and 2012, the researchers found, however, that the national rates of drinking any alcohol are unchanged. In both 2005 and 2012, 56% of Americans reported drinking any alcohol.

Perhaps the most interesting finding of the study, however, is how nationwide levels of binge drinking have been affected by changes in drinking trends among women.

We are seeing some very alarming trends in alcohol overconsumption, especially among women. We also can't ignore the fact that in many US counties a quarter of the people, or more, are binge drinkers.

On a national level, women exhibited a much faster escalation in binge drinking than men. Binge drinking among women rose by 17.5% between 2005 and 2012 and by 4.9% among men.

Most striking disparities in alcohol use found within state lines

Although some regional drinking patterns were observed at a national level - the West, Midwest and New England all exhibited higher levels of alcohol consumption in comparison with other regions, for instance - the authors say that the "most striking" disparities were found within states.

As an example, the researchers explain that rates of overall binge drinking in Texas ranged from 10.8% in Collingsworth County to 35.5% in Loving County - so while one Texan county was well below that national binge drinking average of 18.3%, another county in the same state had levels of binge drinking nearly twice that average.

In the USA, state-level results often mask the full range of what people are experiencing health-wise:

"When you can map out what's happening county by county, over time, and for men and women separately, that's also when you can really pinpoint specific health needs and challenges - and then tailor health policies and programs accordingly."

References:

1.  Drinking patterns in US counties from 2002 to 2012, American Journal of Public Health, doi: 10.2105/AJPH.2014.302313, published online 23 April 2015, abstract.
2.  The Institute for Health Metrics and Evaluation news release, accessed 28 April 2015.