A study published in BMJ (British Medical Journal) indicates that moderate alcohol consumption is linked to a reduced risk of developing rheumatoid arthritis.

According to the study results, the risk of developing rheumatoid arthritis in women with an alcohol consumption of over three alcoholic drinks per week, for a minimum period of 10 years, is 50% lower than that of women who drink no alcohol.

The researchers discovered at both assessments that women who reported drinking over three glasses of alcohol per week in both 1987 and 1997 had a 52% lower risk of developing rheumatoid arthritis a fter adjusting for variables, including age, smoking and dietary habits compared with those who never consumed alcohol.

The findings are the latest in a growing body of evidence that drinking a moderate amount of alcohol in the long term presents no harm and may actually protect against chronic diseases, such as rheumatoid arthritis. However, the researchers warn that the impact of higher alcoholic doses on the risk of rheumatoid arthritis has not yet been established.

Around 1% of the world’s population suffers from rheumatoid arthritis, a chronic inflammatory joint disorder that generally develops in individuals aged between 40 and 50 years. The condition generally affects women three times more often than men. Results from previous studies remain contradictive; whilst some studies have shown that alcohol consumption is linked to a reduced risk of rheumatoid arthritis, others have discovered no such link.

A team of Swedish researchers decided to investigate this controversy by examining the link in 34,141 Swedish women who were born between 1914 and 1948. The team surveyed all participants in 1987 with regard to their alcohol consumption, diet, smoking history, physical activity and education level, conducting the same survey again in 1997. Follow up was a seven-year duration, i.e. from January 2003 to December 2009, when patients were aged between 54 to 89 years. During this period, the team registered 197 new cases of rheumatoid arthritis. The researchers defined one standard glass of alcohol as approximately 500 ml beer, 150 ml of wine or 50 ml of liquor.

The findings revealed that in 1997, the age-standardized rate of rheumatoid arthritis was smaller amongst women who consumed more than four glasses of alcohol per week, i.e. 7 per 10,000 person years compared with those women who consumed less than one glass per week, i.e. 9.1 per 10,000 person years. After adjusting for variables, those who drank more than three glasses of any of the three types of alcohol per week in both 1987 and 1997 had a 52% lower risk of rheumatoid arthritis than those who never consumed alcohol at both assessments.

The results remained largely unchanged after further analyses, which supports the theory that a moderate amount of alcohol could be a protective factor for rheumatoid arthritis. The researchers believe that the finding is most possibly be due to the ability of alcohol to reduce the body’s immune response, which is a relevant factor, given that rheumatoid arthritis is an autoimmune disease, in which the immune system that generally fights infection, attacks the cells that line the joints.

Written by Petra Rattue