Mayo study links smoking exposure to hidradenitis suppurativa in pediatric population

Many studies have shown that smoking is a significant (and modifiable) risk factor for hidradenitis suppurativa. But not much is known about link among children and teens.

But researchers at the Mayo Clinic have helped fill in that void with a case-control study that showed that exposure to passive smoking was associated with a 64% greater risk of hidradenitis suppurativa among those who developed the disease before age 18.

When active and passive smoking were lumped together, the increased risk was almost fivefold.

The study’s co-senior authors, Dawn M. Davis, M.D., and Nessa Aghazadeh Mohandesi, M.D., and their colleagues noted that the smoking exposure was associated with hidradenitis suppurativa being diagnosed at an older age. That observation is a clue that smoking may tip the balance and be a triggering factor in those without a strong genetic predisposition for hidradenitis suppurativa. Other research has found that a family history of hidradenitis suppurativa is reported in about 40% of cases, an indication of genetic predisposition. Cases with a familial background tend to more severe.

This study, published in Pediatric Dermatology in early September, comes as hidradenitis suppurativa is getting more attention. It is a chronic skin inflammatory condition characterized by abscess formation and “tunneling,” the formation of cylinders of keratinocytes in the skin that often fill with pus and blood, which can cause an unpleasant odor. The disease typically presents after puberty. Davis and Mohandesi and their colleagues cite research showing that children and adolescents with the hidradenitis suppurativa are, not surprisingly, often affected by low self-esteem and isolation. The Mayo researchers noted that another challenge of managing the disease in children and teens is that many of the approved systemic therapies have only been tested in adults. The FDA-approved biologics for hidradenitis suppurativa include two of the mainstays of autoimmune disease treatment, Humira (adalimumab) and Costentyx (secukinumab), plus Bimzelx (bimekizumab).

Davis, Mohandesi and their colleagues conducted this study by using diagnostic codes to identify 174 cases of hidradenitis suppurativa in individuals who were diagnosed before they turned 18 between 2010 and 2023. They then matched those cases with 522 healthy controls by age, race and sex assigned at birth. Among the individuals with hidradenitis suppurativa, 48 (27.6%) had active or passive smoke exposure while 80 (15.3%) of the controls had smoke exposure. In both cases and controls, passive smoking exposure wa far more common than active smoking exposure.

Obesity is also a known risk factor for hidradenitis suppurativa, and a markedly greater percentage of the individuals with hidradenitis suppurativa in this study had obesity than those in the control group (29.3% vs. 13.4%). The researchers acknowledge that obesity may confound their results for smoking but also mention that passive smoking is associated with obesity “making this a difficult variable to control.”

Davis, Mohandesi and their colleagues say their study results argue for limiting the smoke exposure of children and adolescents as much as possible. They cite a study published in the journal Nicotine and Tobacco Research in 2013 that showed the motivation to quick smoking is highest when the emphasis is put on the harm it could cost others, not the smokers themselves.

“Knowing a correlation exists between passive smoking exposure and HS [hidradenitis suppurativa] could be an effective motivational factor to include when counseling parents and caregivers of pediatric and adolescent patients with HS on smoking cessation,” they wrote in the results section of their study.