(dailyRx News) If you are obese, all that extra weight is putting a strain on your body. Obesity has been linked to a number of health problems, including several types of arthritis.
Obesity may increase women's risk of psoriatic arthritis - a type of arthritis that happens in people with psoriasis of the skin.
Past studies have shown that obesity is associated with the risk of psoriasis - a skin condition that causes red skin and flaky, silver-white patches.
Less is known about the links between obesity and psoriatic arthritis.
Wenqing Li, PhD, of Brigham and Women's Hospital and Harvard Medical School, and colleagues set out to study how obesity affects the risk of psoriatic arthritis in women.
They found that women who were overweight were almost twice as likely as normal weight women to develop psoriatic arthritis.
Women who were severely obese were more than six times as likely as normal weight women to develop the condition.
"This study provides further evidence linking obesity with the risk of incident psoriatic arthritis among US women," the authors write.
For their study, Dr. Li and colleagues looked at data from more than 89,000 participants in the Nurses Health Study II. They measured participants' body mass index or BMI (a measure of body fat using height and weight), weight change over time, and central obesity.
The risk of psoriatic arthritis was 1.83 times greater in overweight women (BMI of 25 to 29.9) than in normal weight women (BMI of less than 25).
Obese women (BMI of 30 to 34.9) were 3.12 times more likely to develop psoriatic arthritis, while severely obese women (BMI of more than 35) had a 6.46-fold increased risk.
The results also showed that psoriatic arthritis risk was associated with weight change since early adulthood and central obesity (measured as waist and hip circumference and waist-hip ratio).
"These associations existed in a dose-dependent fashion, highlighting the effect of adiposity in the development of psoriatic arthritis," the authors write.
In other words, the risk of psoriatic arthritis may increase as weight change and central obesity increase. This finding highlights how being overweight plays a role in psoriatic arthritis.
This research was supported by the Department of Dermatology at Brigham and Women's Hospital.
Study co-author Abrar A. Qureshi has received a grant from Amgen/Pfizer to study "biomarkers in psoriasis and psoriatic arthritis."
Qureshi is also a consultant for Abbott, Centocor, Novaritis and the CDC.
The study is published in the Annals of the Rheumatic Diseases.