PRAGUE – Patients with the common chronic inflammatory skin disease hidradenitis suppurativa have a sharply increased prevalence of metabolic syndrome, according to the results of three recent case-control studies.
"I think we can say that we have a uniform pattern from three studies showing hidradenitis suppurativa patients have increased risk for the metabolic syndrome, with odds ratios up to 5.8," Dr. Iben M. Miller said at the annual congress of the European Academy of Dermatology and Venereology.
Dr. Iben M. Miller
"The implication is that we need to consider screening our hidradenitis suppurativa patients for cardiovascular risk factors, and – perhaps the most important and difficult thing – to help these patients with lifestyle interventions," added Dr. Miller, a dermatologist at the University of Copenhagen.
She presented updates on two case-control studies, which she is conducting in Denmark, as well as highlights from a third study recently published by dermatologists from the University Hospital Charitè in Berlin.
One of her studies included 374 patients with hidradenitis suppurativa and 15,000 controls drawn from the Danish General Suburban Population Study (GESUS), an ongoing study of the adults initiated in 2010, with enrollment at 15,500 and climbing. Participants are evaluated via detailed questionnaires, periodic physical examinations, and blood work.
All of the hidradenitis suppurativa study patients were adjusted for age, smoking status, and sex because patients with hidradenitis suppurativa are considerably younger, more likely to be female, and have a far greater prevalence of smoking than do control patients.
The hidradenitis suppurativa patients in GESUS proved to have an adjusted 2.35-fold greater likelihood of meeting criteria for metabolic syndrome than do control patients. They had a 2.79-fold increased odds of carrying the diagnosis of diabetes mellitus. They were also 2.36 times more likely to be obese and 2.33-fold more likely to have an increased waist circumference. The hidradenitis suppurativa group also was saddled with increased rates of hypertriglyceridemia and low HDL, with a mean serum triglyceride of 159 mg/dL, compared with 142 mg/dL in control patients, and a mean HDL of 51 mg/dL vs. 57 mg/dL in control patients.
The sole component of metabolic syndrome that was not more prominent in the hidradenitis suppurativa group was hypertension; the 16% increased prevalence of high blood pressure among patients with hidradenitis suppurativa didn’t achieve statistical significance, Dr. Miller noted.
The hidradenitis suppurativa group had an adjusted 1.69-fold greater prevalence of ischemic heart disease and a 1.14-fold greater likelihood of a history of stroke.
Dr. Miller’s second case-control study involved 31 Danish adults hospitalized for surgical treatment of hidradenitis suppurativa and the same 15,000 controls from GESUS. Of note, they were also significantly younger, with a mean age of 40.3 years, compared with 45.9 years in the population-based hidradenitis suppurativa cohort and 54.5 years in control patients. They were also more likely to be female and smokers than the 374 hidradenitis suppurativa patients drawn from GESUS.
The hospitalized hidradenitis suppurativa patients were an adjusted 5.8 times more likely to fulfill the criteria for metabolic syndrome than control patients. They also had a 5.47-fold increased risk of being diagnosed with diabetes. Their rates of all the other metabolic syndrome components were higher than in the GESUS hidradenitis suppurativa patients, as well. "I think that’s probably because the hospital cases have a greater degree of disease severity," said Dr. Miller.
The recently published German case-control study (PLoS ONE 7: e31810. [doi:10.1371/journal.pone.0031810]) included 80 patients hospitalized for surgical treatment of hidradenitis suppurativa and 100 age- and sex-matched controls. The prevalence of metabolic syndrome was 40% among the hidradenitis suppurativa cohort, compared with 13% in controls. The adjusted odds ratio was 4.46%.
The hidradenitis suppurativa group had a 5.88-fold increased likelihood of central obesity, a 4.09-fold greater rate of hyperglycemia, a 2.24-fold increase in hypertriglyceridemia, and 4.56-fold greater odds of low HDL.
An increased prevalence of metabolic syndrome has previously been shown in patients having other chronic inflammatory diseases, including psoriasis and rheumatoid arthritis. The German study provides the first published evidence that the same is true for hidradenitis suppurativa, a disease that affects up to 4% of the adult population, noted Dr. Miller.
The German dermatologists noted in their study results that the prevalence of metabolic syndrome and degree of metabolic derangement appear to be even greater among hidradenitis suppurativa patients than in those with psoriasis, particularly in light of the fact that patients with hidradenitis suppurativa tend to develop metabolic syndrome at a younger age.
As to the mechanism, the investigators reported that chronic inflammation may not be the driving force behind development of metabolic syndrome in patients with hidradenitis suppurativa. Just the opposite: They speculated that metabolic abnormalities may actually trigger hidradenitis suppurativa. Dr. Miller deemed that an intriguing hypothesis that’s far from proven.