What is known about smoking and hidradenitis suppurativa?

01

HS is not a hygiene diagnosis

Systematic reviews find smoking much more common among people with HS, but observational association is not randomized proof of causation.

HS, acne, isolated boils, folliculitis and hygiene problems are not interchangeable labels, and the page cannot identify tunnels or scarring.

[1][3]

02

Why the association varies between studies

Follicular blockage, immune signalling and tissue inflammation are research pathways, not a test showing why one lesion occurred.

Diagnostic definitions, severity, current/former smoking and adjustment for body composition vary and contribute to heterogeneity.

[1]

03

A large odds ratio is not an individual probability

The 2024 review pooled studies using different diagnostic and sampling methods. Some came from national data, others from specialist clinics; that mix is part of the reason results varied strongly. An odds ratio compares odds between study groups, not the fraction of people who will develop HS. The European S2k guideline also says there is no randomized trial showing that smoking cessation reduces existing HS severity. Evidence on new diagnosis cannot fill that gap.

[1][2]

04

Two questions for a skin-care team

Ask separately about the diagnosis and about what evidence supports a proposed change in care. A smoking association does not justify blaming a person for lesions or delaying treatment until they quit. Personal nodules, drainage and treatment choices belong with qualified local dermatology.

[1][3]