Epidemiology, Comorbidities, and Prescription Patterns of Korean Prurigo Nodularis Patients: A Multi-Institution Study

Abstract

Prurigo nodularis (PN) is a chronic dermatosis typified by extraordinarily itchy nodules. However, little is known of the nature and extent of PN in Asian people. This study aimed to describe the epidemiology, comorbidities, and prescription pattern of PN in Koreans based on a large dermatology outpatient cohort. Patients with PN were identified from the Catholic Medical Center (CMC) clinical data warehouse. Anonymized data on age, sex, diagnostic codes, prescriptions, visitation dates, and other relevant parameters were collected. Pearson correlation analysis was used to calculate the correlation between PN prevalence and patient age. Conditional logistic regression modeling was adopted to measure the comorbidity risk of PN. A total of 3591 patients with PN were identified at the Catholic Medical Center Health System dermatology outpatient clinic in the period 2007–2020. A comparison of the study patients with age- and sex-matched controls (dermatology outpatients without PN) indicated that PN was associated with various comorbidities including chronic kidney disease (adjusted odds ratio (aOR), 1.48; 95% confidence interval (CI), 1.29–1.70), dyslipidemia (aOR, 1.88; 95% CI, 1.56–2.27), type 2 diabetes mellitus (aOR, 1.37; 95% CI, 1.22–1.54), arterial hypertension (aOR, 1.50; 95% CI, 1.30–1.73), autoimmune thyroiditis (aOR, 2.43; 95% CI, 1.42–4.16), non-Hodgkin’s lymphoma (aOR, 1.95; 95% CI, 1.23–3.07), and atopic dermatitis (aOR, 2.16, 95% CI, 1.91–2.45). Regarding prescription patterns, topical steroids were most favored, followed by topical calcineurin inhibitors; oral antihistamines were the most preferred systemic agent for PN. PN is a relatively rare but significant disease among Korean dermatology outpatients with a high comorbidity burden compared to dermatology outpatients without PN. There is great need for breakthroughs in PN treatment.

Disease burden and treatment satisfaction in patients with prurigo nodularis in Japan

“…The long duration of the disease in these patients (median 36 months) may also contribute to accumulated prevalence of OCS and cyclosporine use. Medication use in the current study was generally similar to that reported in Korean and European studies, where TCS and antihistamines were the major medications, and where there was OCS use of >20% 26,27 . Taken together with our present study, there is a worldwide, unmet medical need for novel effective therapies in patients with severe PN.…”

Chronic prurigo

“…29 A Korean study found that prurigo nodularis was associated with chronic kidney disease (adjusted odds ratio 1Á48), dyslipidemia (1Á88), type 2 diabetes mellitus (1Á37), arterial hypertension (1Á50), autoimmune thyroiditis (2Á43), non-Hodgkin lymphoma (1Á95) and atopic dermatitis (2Á16). 30 Higher frequency and higher severity were shown in African Americans by comparison with other parts of the US population. 31 There is obviously no relationship with Fitzpatrick phototypes nor skin pigmentation.…”

“…A study of 223 patients from Finland also found frequent cardiovascular, respiratory, psychiatric or endocrine comorbidities 29 . A Korean study found that prurigo nodularis was associated with chronic kidney disease (adjusted odds ratio 1·48), dyslipidemia (1·88), type 2 diabetes mellitus (1·37), arterial hypertension (1·50), autoimmune thyroiditis (2·43), non‐Hodgkin lymphoma (1·95) and atopic dermatitis (2·16) 30 …”

Alterations in epidermal function in type 2 diabetes: Implications for the management of this disease

“…74,75 Prurigo nodularis, another inflammatory dermatosis, is also associated with type 2 diabetes (adjusted odds ratio 1.37; 95% CI 1.22-1.54). 76 A link between atopic dermatitis and type 2 diabetes has also been demonstrated, with an odds ratio of 1.52 (95% CI 1.16-1.99) although some studies showed reduced odds of type 2 diabetes in patients with atopic dermatitis (odds ratio 0.78; 95% CI 0.71-0.84). 77,78 The reduced odds ratio in some patients with atopic dermatitis could be because those patients had already received anti-inflammatory treatment.…”

“…Epidemiological studies show that the risk of type 2 diabetes in subjects with psoriasis is higher than those without psoriasis (age‐adjusted relative risk 1.21, 95% confidence interval [CI] 1.01–1.44; body mass adjusted relative risk 1.64, 95% CI 1.23–2.18) 74,75 . Prurigo nodularis, another inflammatory dermatosis, is also associated with type 2 diabetes (adjusted odds ratio 1.37; 95% CI 1.22–1.54) 76 . A link between atopic dermatitis and type 2 diabetes has also been demonstrated, with an odds ratio of 1.52 (95% CI 1.16–1.99) although some studies showed reduced odds of type 2 diabetes in patients with atopic dermatitis (odds ratio 0.78; 95% CI 0.71–0.84) 77,78 .…”