Some studies have suggested that moderate drinkers have a lower risk of developing rheumatoid arthritis, and now new findings link the habit to a slower progression of the joint disease.
In a study that followed 2,900 adults with rheumatoid arthritis (RA), Swiss researchers found that light-to-moderate drinkers showed slower progression in their joint damage compared with non-drinkers. Heavy drinkers, on the other hand, showed the greatest progression.
The findings, reported in the journal Arthritis & Rheumatism, are based on X-ray evidence of patients' joint damage and its progression over an average of four years.
The difference seen in moderate drinkers' and non-drinkers' progression was not substantial enough to be apparent in daily life — that is, worse symptoms or more disability in the non-drinkers, according to Dr. Axel Finckh, of University Hospital of Geneva, one of the researchers on the study.
However, he told Reuters Health in an email, if the slower progression were maintained over decades, it could become important.
The findings are in line with past research linking moderate drinking to a lower risk of developing RA, according to Finckh and his colleagues.
There is also animal research suggesting that alcohol may inhibit arthritis, possibly by reducing inflammation. Heavy drinking, on the other hand, seems to promote inflammation.
However, whether moderate drinking itself slows RA progression is not certain. More studies are needed to confirm the current findings, Finckh said, and even then, RA patients would not be advised to take up drinking.
Finckh pointed to the example of heart disease, where many studies have suggested a protective effect of moderate drinking, but — owing to the potential risks of drinking — experts do not advise people to start drinking for the sake of their hearts.
The current findings are based on 2,908 Swiss adults who were part of a national database on RA patients. All had had at least two sets of X-rays of their hands and feet over time, and had been followed for four years, on average.
Overall, 37 percent said they were non-drinkers at the outset, while the rest drank at least occasionally. The researchers found that both occasional drinkers and those who drank once per day generally had less joint damage progression over time than non-drinkers.
Study patients' drinking habits remained linked to RA progression when the researchers accounted for a number of other factors, including age, RA medication use, smoking and the length of time each patient had had the disease.
The relationship between drinking and joint damage progression was stronger among men than women, however.
That sex difference was unexpected, according to Finckh and his colleagues, and the reasons for it are not clear. One possibility, they note, is the overall difference in alcohol "dose" between men and women; 27 percent of men said they drank once per day, versus only 14 percent of women.
The findings, according to the researchers, suggest that if people with RA already drink moderately, they should not be encouraged to stop.
"Further research is however required to better understand the impact of alcohol consumption on RA," they add.