Research Shows Hidradenitis Suppurativa Impacts 1% Globally, With Women More Affected

About 1% of people worldwide have hidradenitis suppurativa (HS)—a higher rate than past reports—with women more likely than men to be affected, according to a recent study in JAMA Dermatology.

HS is a chronic inflammatory skin disease that causes painful nodules and abscesses, typically in areas where skin rubs together, such as the underarms, groin and under the breasts. Frequently misdiagnosed as acne or boils, HS can lead to scarring, restricted mobility and a major reduction in quality of life.

The condition is also linked to higher mortality, psychosocial burden and metabolic and inflammatory complications. Despite its impact, global data on HS has been limited, and past findings were inconsistent due to differences in study design and methodology.

To address these gaps, the Global Hidradenitis Suppurativa Atlas (GHiSA) launched the Global Prevalence Study (GPS) to measure HS worldwide and examine variations by sex, age, body mass index (BMI), smoking, economic indicators and geography.

Researchers conducted cross-sectional surveys, in which healthy adults alongside patients at outpatient clinics completed a screening questionnaire. Those who screened positive were examined by HS-trained physicians to confirm diagnosis, while about 10% of participants with negative screens were randomly examined to test for accuracy. Only studies following GHiSA methods and completed before May 19, 2023, were included.

Data from each study was gathered using a standardized form, including geographical location, prevalence estimates with 95% confidence intervals and country-level Human Development Index (HDI) and GDP. Prevalence estimates were pooled using a random-effects model, and heterogeneity was assessed with I² and τ². Logit transformations were applied, and meta-regression examined associations between risk factors and prevalence differences. Analyses were performed in R using the metafor package.

Out of the 74 countries invited to participate, 51 were excluded due to nonresponse, failure to start or complete the study, lack of ethical approval, or protocol deviations. The final analysis included 23 countries who were in 25 studies across six continents, with a pooled dataset of 22,743 participants. It was revealed that 247 were diagnosed with HS. The median age of patients with HS was 34.5 years, and 55.6% were female.

The global prevalence of HS, based on the random-effects model, was 0.99%. Country-level prevalence ranged from 0.13% in Bangladesh to 4.07% in Saudi Arabia, with eight countries exceeding the global average.

There was much variation in HS rates between countries. When looking at continents and regions, no significant differences were found. The only factor linked to higher HS rates was sex, with women more likely to be affected. Other factors, including age, BMI, smoking and other indicators including GDP and HDI, did not show a clear connection.

Overall, this study is the first and largest of its kind to estimate global HS prevalence using a consistently designed approach. By including multiple countries and applying standardized methods, it reduced bias commonly seen in pooled prevalence studies and captured data from previously underrepresented regions.

The methodology provided a more reliable estimate, confirming that HS is more common than previously recognized and highlighting sex as a key factor in disease distribution.

Limitations in the study include the inclusion of only 23 countries, leaving gaps in global coverage, and potential influences from differences in language, culture and healthcare systems. Selection and nonresponse bias are possible because participation relied on societies with available resources.

The study also did not examine how severe HS was, looked only at cigarette smoking, and used combined data for analysis, which could hide differences between individual patients.

Study authors recommend that future research explore environmental, socioeconomic and lifestyle factors and look at links with disease severity, BMI, and alternative tobacco use, as well as include additional countries to better understand the variations in HS prevalence worldwide.