Psoriasis was associated with a 59% increased prevalence of diabetes and a 27% increased risk of developing it, according to the results of a meta-analysis of 27 observational studies.
For patients with severe psoriasis, the prevalence of diabetes was nearly doubled, April W. Armstrong, MD, MPH, Director of the Clinical Research Unit and Teledermatology Program in the Department of Dermatology, University of California, Davis, Sacramento, and colleagues report in an article published online October 15 in the Archives of Dermatology.
"[O]ur findings support a robust association between psoriasis and diabetes. Patients with psoriasis, especially those with severe psoriasis, should be educated about the increased risk of developing diabetes," the authors write.
In an interview with Medscape Medical News, Dr. Armstrong added that the findings also support the emerging view that psoriasis is not merely a skin disease but also an example of "cutaneous manifestations of systemic disease."
A Window Into the Body
"Some skin diseases are just skin diseases, while others serve as a window to what's going on inside the body. The paradigm has shifted with psoriasis.... We're finding associations with other diseases for which we could potentially intervene earlier and potentially prevent long-term complications."
She added that dermatologists should make sure that patients with psoriasis, particularly those with severe disease, have a primary care physician who can screen for diabetes and provide appropriate management. In addition, she noted, in the primary care setting, "Diabetes is pretty prevalent already, so identifying patients at higher risk than the general population is important."
The analysis included 22 different studies, 6 of which were cross-sectional and 16 case-control in design. They were conducted in diverse settings, including large outpatient databases, insurance claims, or inpatient samples. Two of the studies reported more than 1 cohort. Each of those was treated as a separate study, for a total of 27 studies included in the meta-analysis. Of those studies, 22 reported diabetes prevalence and 5 reported incidence.
Using statistical modeling to account for heterogeneity among the studies, the odds ratio for prevalence of diabetes in patients with psoriasis was 1.59 (95% confidence interval [CI], 1.38 - 1.83) compared with those without psoriasis. Analysis of the 4 studies reporting the association of mild psoriasis with the prevalence of diabetes gave a pooled odds ratio of 1.53 (95% CI, 1.16 - 2.04), whereas the 5 studies reporting diabetes prevalence with severe psoriasis yielded a pooled odds ratio of 1.97 (95% CI, 1.48 - 2.62).
Among the 5 studies that assessed incidence, psoriasis was associated with a relative risk of 1.27 (95% CI, 1.16 - 1.40) for developing diabetes. In a study that included 3 separate cohorts, psoriasis was associated with increased incidence of diabetes among patients younger than 60 years (multivariate relative risk, 1.26; 95% CI, 1.08 - 1.46), but not in older patients with psoriasis (relative risk, 0.91; 95% CI, 0.69 - 1.20).
Mechanism Unclear
The mechanism for the association between psoriasis and diabetes is not clear, but previous studies have demonstrated links between psoriasis and multiple cardiovascular risk factors, including diabetes, hyperlipidemia, hypertension and obesity, as well as an increased risk for major adverse cardiac events.
A common inflammatory milieu, promoted by the secretion of adipokines by metabolically active adipose tissue, may be the underlying mechanism connecting psoriasis, diabetes, obesity, and other cardiometabolic risk factors, Dr. Armstrong told Medscape Medical News.
One expert who has published extensively in this area, Joel M. Gelfand, MD, MSCE, called Dr. Armstrong and colleagues' article "the most comprehensive data synthesis to date in order to evaluate the association between psoriasis and diabetes."
Dr. Gelfand, associate professor in the Department of Dermatology and the Department of Epidemiology at the University of Pennsylvania, Philadelphia, told Medscape Medical News that the findings of the current meta-analysis are consistent with a study he and his colleagues published last month in the Archives of Dermatology, in which they found psoriasis to be a risk factor for incident diabetes independent of traditional risk factors.
He advised, "Patients with psoriasis, especially if disease is more severe, should be educated about the risk of diabetes, undergo appropriate medical screenings for the disease, exercise regularly and eat a healthy diet and maintain a healthy body weight in order to reduce the risk of diabetes and its complications."
Dr. Armstrong has received research grants and/or consultant honoraria from Abbott Laboratories, Amgen, and Janssen Pharmaceuticals Inc. Dr. Gelfand has been an investigator and/or consultant for Amgen, Abbott, Merck, Centocor, Pfizer, Celgene, Novartis, and Genentech.
Arch Dermatol. Published online October 15, 2012. Abstract
Medscape Medical News © 2012 WebMD, LLC
Send comments and news tips to news@medscape.net.
Cite this: Psoriasis Linked to Heightened Risk for Diabetes - Medscape - Oct 18, 2012.
