EXPERT ANALYSIS FROM WCD 2015
VANCOUVER (FRONTLINE MEDICAL NEWS) – Dermatologists and primary care physicians working collaboratively have a golden opportunity to improve the long-term health of pediatric psoriasis patients by addressing their predisposition to components of the metabolic syndrome, Dr. Amy S. Paller declared at the World Congress of Dermatology.
“I think we as dermatologists should be in touch with the primary care doctors of every one of our children with psoriasis. Together, we should be thinking about whether the child has metabolic issues and working jointly to most effectively counsel and evaluate these children for their potential risk for these metabolic disorders,” said Dr. Paller, professor and chair of the department of dermatology and professor of pediatrics at Northwestern University, Chicago.
Pediatric psoriasis is commonly associated with other comorbid conditions in addition to metabolic disorders. But the metabolic syndrome has recently become the focus of increasing attention given that cardiovascular disease is the No. 1 cause of death in the United States, and it appears that children with psoriasis may be getting a jump start on the atherosclerotic process.
By now, it’s well established that plaque psoriasis in adults is strongly associated with increased risks of diabetes, obesity, dyslipidemia, the metabolic syndrome, and cardiovascular disease. Mounting evidence indicates children and adolescents with psoriasis face the same risks.
Everyone knows how difficult it can be to make the long-term lifestyle changes that reverse obesity and its related metabolic disorders. But dermatologists, pediatricians, and family physicians have some leverage when it comes to pediatric psoriasis.
“Think about the fact that 30% of children with psoriasis have a first-degree relative with psoriasis, usually a parent. I think we need to think about counseling young adults with psoriasis early on, especially if that adult is overweight or obese, about the need for adopting a healthy lifestyle. If they do that, it’s not just for themselves but for their children, and we just might prevent pediatric psoriasis in that family or temper its severity through that healthy lifestyle intervention,” Dr. Paller continued.
The hope is that effectively addressing the metabolic comorbidities of pediatric psoriasis will modulate and improve the skin disease; in other words, that weight loss could improve psoriasis. As yet, however, that’s just a hope, as there is no persuasive supporting evidence.
“We’re looking towards ongoing adult trials to give us some clues about whether that’s the case,” she said.
Evidence for comorbidities
Some of the key evidence regarding the metabolic comorbidities of pediatric psoriasis comes from a landmark German epidemiologic study involving 33,981 pediatric psoriasis patients. The prevalence of psoriasis in German youth rose linearly from 0.12% at age 1 year to 1.2% at age 18. Pediatric psoriasis patients had significantly higher rates of diabetes, hyperlipidemia, obesity, and hypertension than did nonpsoriatic controls ( Br. J. Dermatol. 2010;162:633-6 ).
A Kaiser Permanente study of nearly 711,000 youths aged 2-19 years showed that those who were overweight were 2.8-fold more likely than normal-weight youth to have severe or widespread psoriasis, while those who were moderately obese were at 2.9-fold increased risk and extremely obese youth were at 4.2-fold increased risk. Among adolescents, having psoriasis was associated with significantly higher mean total and LDL cholesterol, triglycerides, and alanine aminotransferase levels ( J. Pediatr. 2011;159:577-83 ).
Recent evidence suggests that even before increased levels of LDL cholesterol and triglycerides are apparent in children with psoriasis, abnormalities in lipid function are present and may potentially serve as a novel marker for early cardiovascular risk. Dr. Paller cited a study presented by Dr. Wynnis L. Tom of Rady Children’s Hospital, San Diego, at the 2015 annual meeting of the Society for Investigative Dermatology. The case-control study included 50 children with psoriasis and 50 matched controls with a mean age of 13 years.
Like other investigators, Dr. Tom found that the psoriatic children had higher waist/hip ratios and more insulin resistance. While fasting lipid levels didn’t differ between the two groups, the psoriasis patients had significantly higher levels of atherogenic apolipoprotein B, fewer of the particularly cardioprotective large-size HDL particles, and reduced HDL efflux capacity. Stay tuned regarding these potential early markers, Dr. Paller advised.
She was lead author of a 409-patient international study that showed the risks of obesity and a high waist circumference rise with greater severity of pediatric psoriasis. Children with severe psoriasis were at 4.92-fold increased risk of obesity, compared with controls, while even those with mild psoriasis were at 3.6-fold increased risk ( JAMA Dermatol. 2013;149:166-76 ).
Which comes first?
The question arises: Which comes first in children, the excess adiposity or the psoriasis? Dr. Paller said that although the final word isn’t in, she and her coworkers found in a pilot study of 27 overweight or obese children with psoriasis that excess adiposity typically came first. Moreover, among the roughly one-half of children with a family history of obesity, onset of psoriasis occurred a full 3 years earlier than in those without a positive family history ( JAMA Dermatol. 2014;150:573-4 ).
In another small study, this by investigators at Tufts University, Boston, 6 of 20 children with psoriasis (30%) met criteria for the metabolic syndrome, compared with just 1 of 20 matched nonpsoriatic controls ( Pediatr. Dermatol. 2013;30:700-5 ).
Dr. Paller said that if dermatologists and primary care physicians are to successfully collaborate in tackling the comorbid metabolic disorders associated with pediatric psoriasis, a prerequisite is that dermatologists are going to have to do a better job of educating their primary care colleagues about the skin disease as manifest in children.
“I think it’s very important that pediatricians are aware that psoriasis is a risk factor for metabolic syndrome. But pediatric psoriasis is often misdiagnosed by primary care physicians who mistake it for eczema or tinea infection or contact dermatitis,” according to the pediatric dermatologist.
In one eye-catching Australian study, she noted, a mere 9% of patients with pediatric psoriasis were correctly diagnosed before referral to a dermatologist ( Australas. J. Dermatol. 2012;53:98-105 ).
Pediatric psoriasis: not just skin deep
In addition to the increased risk of metabolic disorders faced by pediatric psoriasis patients, other common comorbidities include depression, anxiety disorders, impaired self-esteem and quality of life, arthritis, and Crohn’s disease, Dr. Paller observed.
• Quality of life. “The quality of life impact of psoriasis is profound. It’s a highly visible disorder, which affects the development of self-esteem and social relationships,” Dr. Paller said.
Investigators at Texas A&M University applied the Pediatric Quality of Life Inventory Version 4.0 to 208 patients aged 2-17 years with moderate to severe psoriasis and compared the results to published data on children with arthritis, asthma, diabetes, and psychiatric disorders. Health-related quality of life turned out to be more impaired in the psoriasis patients than in those with diabetes. The quality-of-life impairment associated with pediatric psoriasis was comparable to that of having asthma or arthritis, albeit not as severe as for pediatric psychiatric disorders ( Eur. J. Pediatr. 2012;171:485-92 ).
• Psychiatric disorders. A study of more than 7,400 pediatric psoriasis patients concluded they had an adjusted 25% increased risk of developing depression, compared with psoriasis-free controls, as well as a 32% increased risk of anxiety disorders and a 55% greater risk of bipolar disorder ( J. Am. Acad. Dermatol. 2012;67:651-7.e2 ).
• Psoriatic arthritis. An estimated 1 in 10 U.S. children with psoriasis report having arthritis, often classified as juvenile idiopathic arthritis ( JAMA Dermatol. 2013;149:1180-5 ).
• Crohn’s disease. A large German epidemiologic study concluded that psoriasis was associated with a 3.69-fold increased risk of Crohn’s disease. There was no increased risk of ulcerative colitis ( Br. J. Dermatol. 2010;162:633-6 ).
Dr. Paller reported receiving research grants from Amgen and Leo and serving as a consultant to AbbVie.
