The influence of age and sex in sarcoidosis

Epidemiology of Sarcoidosis

Sarcoidosis is a systemic, granulomatous disease with variable presentation earning it the term "the great mimicker." The current epidemiology confirms that the disease occurs worldwide, affecting both sexes, and all races, ethnicities, and ages. To date, no causal exposure or agent has been identified. The organ systems most frequently affected by sarcoidosis are also those with greatest exposure to the natural world suggesting environmental and lifestyle contributions to the disease. These include particulate matter, microorganisms, nicotine, and obesity. In this article, we review the epidemiology of sarcoidosis and discuss these non-genetic risk factors in the hope of providing important insight into sarcoidosis and stimulating future research.

Demographics, Cutaneous Manifestations, and Comorbidities Associated with Progressive Cutaneous Sarcoidosis: A Retrospective Cohort Study

Background: Sarcoidosis is a multisystem granulomatous disease with a wide variety of presentations and clinical courses. Cutaneous manifestations and comorbidities associated with sarcoid prognosis remain understudied. Methods: An EPIC query was run for patients age 18+ at the Johns Hopkins Hospital with a diagnosis of sarcoidosis of the skin according to the ICD-10-CM code D86.3. Data were obtained from a population-based sample of 240 patients from 2015 to 2020. Results: A total of 240 patients were included in the cohort study. The mean (SD) age was 43.76 (11.72) years, and 30% of participants were male; 76.25% of patients identified as black, 19.58% as white, and 4.17% as other. The average age of onset in remissive patients was significantly higher than progressive (47 ± 12 vs. 40 ± 10, p = 0.0005); 49% of black patients experienced progressive sarcoid compared to 32.6% of white patients (p = 0.028). Progressive disease was associated with the presence of lupus pernio (aOR = 3.29, 95% CI, 1.60-6.77) and at least one autoimmune comorbidity (aOR 6.831, 95% CI 1.819-11.843). Conclusions: When controlling for patient demographics, lupus pernio and the presence of at least one autoimmune condition were associated with progressive cutaneous sarcoidosis.

Sex differences in the genetics of sarcoidosis across European and African ancestry populations

Background

Sex differences in the susceptibility of sarcoidosis are unknown. The study aims to identify sex-dependent genetic variations in two clinical sarcoidosis phenotypes: Löfgren's syndrome (LS) and non-Löfgren's syndrome (non-LS).

Methods

A meta-analysis of genome-wide association studies was conducted on Europeans and African Americans, totaling 10,103 individuals from three population-based cohorts, Sweden (n = 3,843), Germany (n = 3,342), and the United States (n = 2,918), followed by an SNP lookup in the UK Biobank (UKB, n = 387,945). A genome-wide association study based on Immunochip data consisting of 141,000 single nucleotide polymorphisms (SNPs) was conducted in the sex groups. The association test was based on logistic regression using the additive model in LS and non-LS sex groups independently. Additionally, gene-based analysis, gene expression, expression quantitative trait loci (eQTL) mapping, and pathway analysis were performed to discover functionally relevant mechanisms related to sarcoidosis and biological sex.

Results

We identified sex-dependent genetic variations in LS and non-LS sex groups. Genetic findings in LS sex groups were explicitly located in the extended Major Histocompatibility Complex (xMHC). In non-LS, genetic differences in the sex groups were primarily located in the MHC class II subregion and ANXA11. Gene-based analysis and eQTL enrichment revealed distinct sex-specific gene expression patterns in various tissues and immune cell types. In LS sex groups, a pathway map related to antigen presentation machinery by IFN-gamma. In non-LS, pathway maps related to immune response lectin-induced complement pathway in males and related to maturation and migration of dendritic cells in skin sensitization in females were identified.

Conclusion

Our findings provide new evidence for a sex bias underlying sarcoidosis genetic architecture, particularly in clinical phenotypes LS and non-LS. Biological sex likely plays a role in disease mechanisms in sarcoidosis.

Sex Differences in Temporal Trends in Hospitalizations and In-Hospital Mortality in Patients with Sarcoidosis in Spain from 2001 to 2020

(1) Background: We aimed to analyze temporal trends in hospitalization and in-hospital mortality (IHM) in patients with sarcoidosis in Spain from 2001−2020. (2) Methods: Using the Spanish National Hospital Discharge Database, we included patients (aged ≥ 20 years) hospitalized with a sarcoidosis code in any diagnostic field. (3) Results: We included 44,195 hospitalizations with sarcoidosis (56.34% women). The proportion of women decreased over time, from 58.76% in 2001 and 2002 to 52.85% in 2019 and 2020 (p < 0.001). The crude rates per 100,000 inhabitants increased by 4.02% per year among women and 5.88% among men. These increments were confirmed using Poisson regression analysis, which yielded an IRR of 1.03; 95% CI 1.01−1.04 for women and 1.04; 95% CI 1.02−1.06 for men. During the study period, no significant sex differences in IHM were recorded. Older age, COVID-19, respiratory failure, and the need for mechanical ventilation were independent predictors of IHM in men and women hospitalized with sarcoidosis, with IHM remaining stable over time. (4) Conclusions: The number of hospital admissions among patients with sarcoidosis in Spain increased threefold from 2001 to 2020. Although the incidence rates were higher in women, the trend followed that the incidence rates between sexes became closer. IHM was similar among men and women, with no significant change over time in either sex after multivariable analysis.