Commentary: AD, RA, Probiotics, and a New JAK inhibitor, June 2023

The most common adverse events were acne, headache, upper respiratory tract infection, creatine phosphokinase (CPK) level elevations, and nasopharyngitis. I'm confident that none of my patients will have CPK elevations detected, because I won't be testing for it. I suspect that CPK elevations come from people being more physically active when their skin clears up.

I have the sense that our comfort with Janus kinase (JAK) inhibition will grow rapidly as we use the drug for patients with vitiligo, alopecia areata, resistant atopic dermatitis, and other diseases. Many of us are comfortable with methotrexate, dapsone, cyclosporine, and mycophenolate; our comfort with JAK inhibitors for our patients who need it will almost surely follow.

Williams and colleagues did a meta-analysis looking at the relationship between AD and rheumatoid arthritis (RA). They claim that “patients with AD had significantly increased odds of comorbid RA.” This claim should not be taken at face value. What they found was that the observed rate of RA was higher in patients with AD than in controls, and the difference was not something you would see by chance very often. But that does not make something significant. To truly be significant, you'd expect it to be clinically meaningful. The relationship they found — even if not due to chance or to some unmeasured bias — wasn't clinically relevant, in my opinion. RA is a relatively rare phenomenon. If it is barely more common in patients with AD than in controls, it is still rare in AD patients. We don't need to screen for RA in AD patients. We don't need to do anything with this apparent association.

The bottom line is to be wary when you see an article that reports a “significant” finding, especially when it is based on a higher relative risk, like an odds ratio. What we need to know is what the absolute magnitude of the risk is. We need to know how many patients with AD you'd have to see before you'd see one more case of RA due to AD. Williams and colleagues' study doesn't report the information we need as clinicians.

Fijan and colleagues did a meta-analysis to assess the effects of single-strain probiotic lactobacilli on atopic dermatitis. The found a “significant” (meaning, statistically significant) reduction with the lactobacilli treatment compared with placebo. They used the SCORing Atopic Dermatitis (SCORAD) index as the outcome. There was a mean 4.5-unit improvement.

For comparison, Wollenberg and colleagues¹ reported the SCORAD improvement seen with dupilumab: 49- and 46-unit improvements in children and adolescents, respectively.

While I'm sure that patients would love a safe, effective, “all natural” probiotic option for atopic dermatitis, I'm not optimistic that this gut magic is going to work.

Additional Reference

1. Wollenberg A, Marcoux D, Silverberg JI, et al. Dupilumab provides rapid and sustained improvement in SCORing Atopic Dermatitis outcomes in paediatric patients with atopic dermatitis. Acta Derm Venereol. 2022;102:adv00726. doi: 10.2340/actadv.v102.854

The most common adverse events were acne, headache, upper respiratory tract infection, creatine phosphokinase (CPK) level elevations, and nasopharyngitis. I'm confident that none of my patients will have CPK elevations detected, because I won't be testing for it. I suspect that CPK elevations come from people being more physically active when their skin clears up.

I have the sense that our comfort with Janus kinase (JAK) inhibition will grow rapidly as we use the drug for patients with vitiligo, alopecia areata, resistant atopic dermatitis, and other diseases. Many of us are comfortable with methotrexate, dapsone, cyclosporine, and mycophenolate; our comfort with JAK inhibitors for our patients who need it will almost surely follow.

Williams and colleagues did a meta-analysis looking at the relationship between AD and rheumatoid arthritis (RA). They claim that “patients with AD had significantly increased odds of comorbid RA.” This claim should not be taken at face value. What they found was that the observed rate of RA was higher in patients with AD than in controls, and the difference was not something you would see by chance very often. But that does not make something significant. To truly be significant, you'd expect it to be clinically meaningful. The relationship they found — even if not due to chance or to some unmeasured bias — wasn't clinically relevant, in my opinion. RA is a relatively rare phenomenon. If it is barely more common in patients with AD than in controls, it is still rare in AD patients. We don't need to screen for RA in AD patients. We don't need to do anything with this apparent association.

The bottom line is to be wary when you see an article that reports a “significant” finding, especially when it is based on a higher relative risk, like an odds ratio. What we need to know is what the absolute magnitude of the risk is. We need to know how many patients with AD you'd have to see before you'd see one more case of RA due to AD. Williams and colleagues' study doesn't report the information we need as clinicians.

Fijan and colleagues did a meta-analysis to assess the effects of single-strain probiotic lactobacilli on atopic dermatitis. The found a “significant” (meaning, statistically significant) reduction with the lactobacilli treatment compared with placebo. They used the SCORing Atopic Dermatitis (SCORAD) index as the outcome. There was a mean 4.5-unit improvement.

For comparison, Wollenberg and colleagues¹ reported the SCORAD improvement seen with dupilumab: 49- and 46-unit improvements in children and adolescents, respectively.

While I'm sure that patients would love a safe, effective, “all natural” probiotic option for atopic dermatitis, I'm not optimistic that this gut magic is going to work.

Additional Reference

1. Wollenberg A, Marcoux D, Silverberg JI, et al. Dupilumab provides rapid and sustained improvement in SCORing Atopic Dermatitis outcomes in paediatric patients with atopic dermatitis. Acta Derm Venereol. 2022;102:adv00726. doi: 10.2340/actadv.v102.854

The most common adverse events were acne, headache, upper respiratory tract infection, creatine phosphokinase (CPK) level elevations, and nasopharyngitis. I'm confident that none of my patients will have CPK elevations detected, because I won't be testing for it. I suspect that CPK elevations come from people being more physically active when their skin clears up.

I have the sense that our comfort with Janus kinase (JAK) inhibition will grow rapidly as we use the drug for patients with vitiligo, alopecia areata, resistant atopic dermatitis, and other diseases. Many of us are comfortable with methotrexate, dapsone, cyclosporine, and mycophenolate; our comfort with JAK inhibitors for our patients who need it will almost surely follow.

Williams and colleagues did a meta-analysis looking at the relationship between AD and rheumatoid arthritis (RA). They claim that “patients with AD had significantly increased odds of comorbid RA.” This claim should not be taken at face value. What they found was that the observed rate of RA was higher in patients with AD than in controls, and the difference was not something you would see by chance very often. But that does not make something significant. To truly be significant, you'd expect it to be clinically meaningful. The relationship they found — even if not due to chance or to some unmeasured bias — wasn't clinically relevant, in my opinion. RA is a relatively rare phenomenon. If it is barely more common in patients with AD than in controls, it is still rare in AD patients. We don't need to screen for RA in AD patients. We don't need to do anything with this apparent association.

The bottom line is to be wary when you see an article that reports a “significant” finding, especially when it is based on a higher relative risk, like an odds ratio. What we need to know is what the absolute magnitude of the risk is. We need to know how many patients with AD you'd have to see before you'd see one more case of RA due to AD. Williams and colleagues' study doesn't report the information we need as clinicians.

Fijan and colleagues did a meta-analysis to assess the effects of single-strain probiotic lactobacilli on atopic dermatitis. The found a “significant” (meaning, statistically significant) reduction with the lactobacilli treatment compared with placebo. They used the SCORing Atopic Dermatitis (SCORAD) index as the outcome. There was a mean 4.5-unit improvement.

For comparison, Wollenberg and colleagues¹ reported the SCORAD improvement seen with dupilumab: 49- and 46-unit improvements in children and adolescents, respectively.

While I'm sure that patients would love a safe, effective, “all natural” probiotic option for atopic dermatitis, I'm not optimistic that this gut magic is going to work.

Additional Reference

1. Wollenberg A, Marcoux D, Silverberg JI, et al. Dupilumab provides rapid and sustained improvement in SCORing Atopic Dermatitis outcomes in paediatric patients with atopic dermatitis. Acta Derm Venereol. 2022;102:adv00726. doi: 10.2340/actadv.v102.854