Burden of Ocular Comorbidities in Patients With Hidradenitis Suppurativa

Abstract

This case-control study examines the burden of ocular comorbidities in patients with hidradenitis suppurativa.

Hidradenitis suppurativa (HS) is a chronic systemic inflammatory disorder of the terminal follicular epithelium in the apocrine gland–bearing skin. Clinically, it is characterized by lesions, including comedones, papules, pustules, nodules, and fistulas, that are mainly concentrated in axillae, perineal, and submammary areas.¹

Other autoimmune diseases are associated with ocular comorbidities; however, there is a paucity of data on ocular comorbidities in HS.^1,2,3,4 In this article, we aim to quantify the burden of ocular comorbidities in patients with HS.

Methods

IBM Explorys

Explorys (IBM) is a large, real-world, cloud-based aggregate database that was previously validated as a source of epidemiological information. It contains demographic, clinical, laboratory, and treatment information on 72 million unique patients across 369 hospitals in the US, representing almost 15% of the US population.⁵ Institutional review board approval and informed consent is not needed when analyzing information in Explorys because data can be downloaded only in deidentified manner.

Study Design

We performed a case-control study, comparing ocular comorbidities in patients with HS and controls. Patients with HS were identified using the term hidradenitis suppurativa from the Systematized Nomenclature of Medicine-Clinical Terms. Ocular comorbidities were identified using the terms anterior uveitis, posterior uveitis, chronic uveitis, uveitis, scleritis, episcleritis, interstitial keratitis, and conjunctivitis. Patients with other autoimmune diseases known to increase the risk of ocular comorbidities were excluded (ie, psoriasis, ankylosing spondylitis, rheumatoid arthritis, Bechet syndrome, Crohn disease, ulcerative colitis, systemic lupus erythematosus, Marfan syndrome, Down syndrome, Ehlers-Danlos syndrome, diabetes, and HIV).

Statistics

Characteristics of patients with and without HS are presented as frequencies and percentages. Multivariate logistic regression was used to assess differences in ocular comorbidities between patients with HS and controls while adjusting for race and/or sex.

Results

There were 31 400 patients with HS (23 370 women [74.4%]), of whom 4360 (13.89%) had ocular comorbidities compared with 1 654 320 of 51 517 730 control patients (3.2%; P < .001) (Table 1). Anterior uveitis was present in 180 patients with HS (0.6%) vs 46 780 controls (0.1%) (odds ratio [OR], 1.41; 95% CI, 1.27-1.56; P < .001; Table 2). Chronic uveitis was present in 20 patients with HS (0.1%) and 6170 controls (0.01%) (OR, 1.07; 95% CI, 0.65-1.48; P = .21) whereas posterior uveitis was present in 20 patients with HS (0.1%) and 6380 controls (0.01%) (OR, 1.25; 95% CI, 0.83-1.66; P = .21). While the OR of episcleritis was significantly increased among patients with HS (HS, 0.2% vs controls, 0.03%; OR, 2.06; 95% CI, 1.78-2.34; P < .001), the OR of scleritis was not (HS, 0.3% vs controls, 0.03%; OR, 0.39; 95% CI, 0.21-0.56; P = .09). The ORs for keratitis (HS, 0.9% vs controls, 0.2%; OR, 1.54; 95% CI, 1.43-1.66; P < .001) and conjunctivitis (11.9% vs 2.9%; OR, 1.27, 95% CI, 1.24-1.31; P < .001), but not interstitial keratitis (HS, 0.1% vs controls, 0.01%; OR, 1.31; 95% CI, 0.9-1.73; P = .21), were increased among patients with HS.

Table 1. Demographic Characteristics of Patients With HS and Controls Selected in the Study.

Characteristic	No. (%)a		P value
	Patients with HS (n = 31 400)	Controls (n = 51 517 730)
Sex
Male	8030 (25.6)	23 654 540 (45.9)	<.001
Female	23 370 (74.4)	27 863 190 (54.1)
Race
Caucasian	18 470 (58.8)	28 340 670 (55.0)	<.001
African American	10 220 (32.6)	5 243 880 (10.2)
Other	2710 (8.6)	17 933 180 (34.8)
Ocular comorbidities	4360 (13.9)	1 654 320 (3.2)	<.001
Uveitis	210 (0.7)	59 330 (0.1)	<.001
Anterior	180 (0.6)	46 780 (0.1)	<.001
Posterior	20 (0.1)	6380 (0.01)	<.001
Chronic	20 (0.1)	6170 (0.01)	<.001
Conjunctivitis	3730 (11.9)	1 485 990 (2.9)	<.001
Keratitis	290 (0.9)	88 950 (0.2)	<.001
Interstitial	20 (0.1)	31 570 (0.1)	.86
Scleritis	80 (0.3)	14 160 (0.03)	<.001
Episcleritis	50 (0.2)	5890 (0.01)	<.001

Abbreviation: HS, hidradenitis suppurativa.

^aPercentage calculated on the total number of patients with HS or controls.

Table 2. ORs of Ocular Comorbidities in Hidradenitis Suppurativa.

Condition	OR (95% CI)	P value
Uveitisa	1.46 (1.32-1.60)	<.001
Anteriora	1.41 (1.27-1.56)	<.001
Posterior	1.25 (0.83-1.66)	.21
Chronicb	1.07 (0.65-1.48)	.21
Conjuctivitisa	1.27 (1.24-1.31)	<.001
Keratitisa	1.54 (1.43-1.66)	<.001
Interstitialb	1.31 (0.9-1.73)	.21
Scleritisb	0.39 (0.21-0.56)	.09
Episcleritisb	2.06 (1.78-2.34)	<.001

Abbreviation: OR, odds ratio.

^aAdjusted for race and sex.

^bAdjusted for race.

Discussion

Among this cohort, patients with HS had greater rates of ocular comorbidities compared with controls. There are several case reports and case series describing ocular comorbidities among patients with HS.^1,2 A study examining ocular comorbidities in patients with HS demonstrated that uveitis was the most common, followed by scleritis and keratitis¹; however, they included patients with other autoimmune diseases. In this study, episcleritis had the strongest association, followed by keratitis and uveitis. A case report described an association with Mooren-type ulceration³; however, we were unable to evaluate this condition in our database. Saygin et al¹ found that patients with HS with ocular comorbidities rarely respond to dermatological topical treatment and have a better response to anti-TNF-α therapy.

The limitations of this study are a limited ability to account for confounders because of the aggregate nature of data and misclassification bias. However, the size of the database is a strength.

Among this cohort, patients with HS had an increased burden of ocular comorbidities. These data suggest that, while uncommon, a brief assessment of ocular history and symptoms during routine visits could help identify patients with HS who should see an ophthalmologist.