By Dr Ananya Mandal, MD

According to a new study, women who regularly drink beer may be increasing their risk of developing psoriasis – a disease of the skin. Light beer and wine are not associated with such a risk, the study says. Psoriasis is a chronic skin disease characterised by itchy red scaly patches that most commonly appear on the knees, elbows and scalp or anywhere else in the body.

This study was conducted by researchers from Brigham and Women’s Hospital, Harvard Medical School, and Boston University who studied 82,869 women who had not initially been diagnosed with psoriasis for about 15 years, from 1991 through 2005. Results from another study, Nurses’ Health Study II were also collated with this study.

Results showed that even relatively moderate amounts of beer seemed to increase the risk of psoriasis, with 2.3 drinks a week raising the risk to nearly 80%. Five beers a week more than doubled the risk of being diagnosed with this skin condition, as compared with teetotalers.

According to Dr. Abrar A. Qureshi, assistant professor of dermatology at Brigham and Women’s Hospital and Harvard Medical School in Boston and lead author of the article that was published in the December issue of Archives of Dermatology, “We can say that if a woman would like to consume alcohol and if she has a family history of psoriasis or known psoriasis in the past or some other reason she might be predisposed to psoriasis, the alcohol of choice probably should not be non-light beer.”

However Bruce Bebo, director of research and medical programs at the National Psoriasis Foundation feels an in depth look is necessary and there is a “need [for] more investigation to determine whether there’s a real connection or not.” He added that “…from the point of view of the health-care provider, trying to limit alcohol consumption for lots of reasons is important. If this encourages people to limit alcohol consumption, I think that’s a positive outcome, but I don’t think the National Psoriasis Foundation or any physician group would make a recommendation.” Bebo said, “There is evidence that alcohol consumption can affect immune responses and psoriasis is an autoimmune disease…There’s also some evidence that it can affect the biology of (the skin cells known as) keratinocytes. But … then why would it be non-light beer, why not wine or other alcohol? Maybe there’s something in wine that … might reverse the effect.”

Qureshi added that, “When we looked up the components of different alcoholic beverages, one thing that stood out for non-light beer was the amount of protein, gluten in particular…When we stumbled on this, we realized that there have been reports in the past that ingested gluten was associated not just with psoriasis worsening but other autoimmune diseases, such as celiac disease.”

Psoriasis & Mental health

Yet another study in the August issue of the journal found that people who have psoriasis have higher rates of depression, anxiety and even suicidal tendencies. University of Pennsylvania in Philadelphia researchers said, the association was more pronounced in men. Shanu Kohli Kurd, MD, MSCE, MHS, from University of Pennsylvania in Philadelphia, and colleagues write, “Quantifying the relationship between psoriasis and major psychological outcomes is important to identify to which mental health disorders patients with psoriasis may be particularly susceptible…We conducted a large, broadly representative, population-based cohort study to investigate the hypothesis that patients with psoriasis have an increased risk of clinical diagnoses of depression, anxiety, and suicidality (suicidal ideation, suicide attempt, or suicide) compared with the general population.”

They used a General Practice Research Database collected as part of patients’ electronic medical records from 1987 to 2002 and identified 146,042 patients with mild psoriasis, 3956 patients with severe psoriasis, and 766,950 patients without psoriasis. They selected 5 control subjects without psoriasis from the same practices and with similar cohort entry dates as patients with psoriasis. The primary study endpoints were clinical diagnoses of depression, anxiety, and suicidality.

Authors write, “Patients with psoriasis have an increased risk of depression, anxiety, and suicidality…We estimate that in the United Kingdom, in excess of 10 400 diagnoses of depression, 7100 diagnoses of anxiety, and 350 diagnoses of suicidality are attributable to psoriasis annually. It is important for clinicians to evaluate patients with psoriasis for these conditions to improve outcomes.” They conclude, “Recent data suggest that psychiatric comorbidity may negatively affect response to certain psoriasis treatments (eg, photochemotherapy), while other studies suggest that control of psoriasis is associated with improvements in psychological symptoms…Future studies are necessary to determine the mechanisms by which psoriasis is associated with depression, anxiety, and suicidality as well as approaches to prevent such adverse outcomes in patients with psoriasis.”