News - October 2021

High Body Surface Area of Severe Psoriasis Linked to Increased Risk of Developing PsA
In a large prospective population-based cohort study, the body surface area (BSA) of patients with severe psoriasis was assessed to be a strong predictor of developing psoriatic arthritis (PsA), with obesity and depression being additive risk factors, according to a study in Rheumatology.

Data from a United Kingdom-based medical record database, The Health Improvement Network, were used to randomly select patients aged 25 to 60 years for inclusion between 2008 to 2011. Their general practitioners received questionnaires to confirm each patient’s psoriasis diagnosis and an approximate BSA. The BSA was then used to calculate the incidence of PsA, and the authors used Cox proportional hazard ratios to examine the risk of developing PsA by BSA category after covariate adjustments.

A total of 9987 (95%) questionnaires were returned, with 9069 (91%) having confirmed psoriasis and 8881 providing a psoriasis BSA. Of those, 52% of patients had mild psoriasis, 36% moderate psoriasis, and 12% severe psoriasis. Analysis showed that the incidence of PsA was 5.4 cases per 1000 person years. Even after adjusting for age and sex, the authors found that BSA greater than 10%, BSA between 3% and 10%, obesity, and depression were all associated with an incidence of PsA.

Cardiovascular disease is one of the comorbidities already associated with increasing psoriasis severity. This study provided further data surrounding the association of psoriasis severity with developing PsA. The authors concluded that BSA, obesity, and depression all influence the overall risk factor.

Reference
Ogdie A, Shin DB, Love TJ, Gelfand JM. Body surface area affected by psoriasis and the risk for psoriatic arthritis: a prospective population-based cohort study. Rheumatology (Oxford). Published online September 11, 2021. doi:10.1093/rheumatology/keab622

Increased Air Pollution Linked to Atopic Dermatitis and Chronic Inflammatory Skin Diseases
According to a South Korea study published in Clinical and Experimental Dermatology, particulate matter (PM) is associated with atopic dermatitis (AD) and chronic inflammatory skin diseases.

The study authors described PM as a "mixture of solid and liquid particles suspended in air which originates from industrial plants or vehicle emission." Researchers aimed to investigate the associations between PM and AD and other dermatoses using monthly disease statistics from seven South Korean cities. A total of 23,288,000 people from Korea Health Insurance Review and Assessment Service data were included. Monthly visits of AD were estimated with respect to outdoor air pollutants and daily air pollution levels (PM_2.5, PM₁₀, O₃, NO₂, SO₂, and CO).

Increases in air pollution levels were associated with increases in monthly patient visits of AD. Every 10 µg/m³ increase in PM_2.5 and PM₁₀, 1 ppb increase in SO₂, and 100 ppb increased in CO significantly increased the amount of patient visits for AD. O₃ and NO₂ levels were not associated. Increases in PM_2.5 and PM₁₀ were also associated with increases in patient visits for psoriasis, seborrheic dermatitis, and rosacea.

Reference
Park TH, Park S, Cho MK, Kim S. Associations of particulate matter with atopic dermatitis and chronic inflammatory skin diseases in South Korea. Clin Exp Dermatol. Published online August 24, 2021. doi:10.1111/ced.14910

COVID-19 Risk Comparison in Patients With IMIDs vs Matched Non-IMIDs from the General Population
A population-based COVID-19 comparison study examined the incidence of testing and infection between patients with immune-mediated inflammatory diseases (IMIDs), determining that patients across all IMIDs were more likely to be tested for SARS-CoV-2; however, this group tested positive for SARS-CoV-2 at the same rate as patients without IMIDs.

The matched cohort study was conducted among adults in Ontario, Canada, from January 2020 to December 2020. Specific cohorts were created for rheumatoid arthritis (RA), psoriasis, psoriatic arthritis, ankylosing spondylitis, systemic autoimmune rheumatic diseases, multiple sclerosis (MS), iritis, inflammatory bowel disease (IBD), polymyalgia rheumatica, and vasculitis. Based on sociodemographic factors, each patient with an IMID was matched with five healthy patients to estimate the differences in likelihood, frequency, and severity of SARS-CoV-2 testing and infections. Multivariable logistic regressions were used to assess odds of infection.

Researchers studied 2,960,445 patients in total, including 493,499 patients with IMIDs and 2,466,946 patients without IMIDs. They found that patients with IMIDs were more likely to have been tested for SARS-CoV-2 at least once compared with those without IMIDs (27.4% vs 22.7%, respectively). Notably, 0.9% of tests were positive for SARS-CoV-2 in both groups.

Overall, patients with IMIDs had 20% higher odds of testing for SARS-CoV-2, according to the study authors. Further, the odds of infection varied across the different IMIDs but was not significantly elevated for most IMID groups vs non-IMID controls. It was noted, however, that the odds of a SARS-CoV-2 infection were lower in patients with IBD or MS and marginally higher in patients with RA or iritis.

The main results of this COVID-19 comparison study showed that the incidence of SARS-CoV-2 infection was the same between patients across all IMIDs vs patients without IMIDs, but patients with IMIDs were more likely to be tested. The risk of SARS-CoV-2 infection varied across only four specific IMID subgroups.

Reference
Eder L, Croxford R, Drucker AM, et al. Understanding COVID-19 risk in patients with immune mediated inflammatory diseases: a population-based analysis of SARS-CoV-2 testing. Arthritis Care Res (Hoboken). Published online September 6, 2021. doi:10.1002/acr.24781

High Rates of Physical and Psychosocial Comorbidities in Pediatric Patients With HS
Pediatric patients with hidradenitis suppurativa (HS) have high rates of physical and psychosocial comorbidities, according to a recent study in Pediatric Dermatology.

Researchers in a retrospective analysis aimed to describe physical and psychosocial comorbidities in a cohort of pediatric patients with HS. Data on patient demographics, disease characteristics, and physical and psychosocial comorbidities in pediatric patients with HS were collected and analyzed from a single academic institution.

Analysis included 72 patients, with a mean age of HS onset of 12.6 years. Higher rates of metabolic and endocrine abnormalities, obesity, polycystic ovary syndrome, and acne were found in the study cohort compared with the general United States pediatric population. Patients also had an increased rate of anxiety or depression and asthma or other airway diseases.

“Pediatric patients with HS face a high-comorbidity burden,
especially with psychiatric conditions,” concluded the study authors. “Early identification, including routine mental health screening, and management of comorbidities is warranted in the pediatric HS population,” they added.

Reference
Seivright JR, Collier E, Grogan T, Hogeling M, Shi VY, Hsiao JL. Physical and psychosocial comorbidities of pediatric hidradenitis suppurativa: a retrospective analysis. Pediatr Dermatol. Published online August 31, 2021. doi:10.1111/pde.14765