Clinical characteristics of sarcoidosis patients in Belgium.

BACKGROUND: Sarcoidosis is a non-caseating granulomatous disease, mostly affecting previously healthy persons in their fourth and fifth decade. In Belgium, there is a paucity of epidemiological data concerning sarcoidosis and it is unknown to what respect national data on sarcoidosis relates to the global epidemiology of the disease. OBJECTIVES: In this cohort study we describe the patient population in an academic center of reference, serving both as a regional care center and a center for a tertiary referral. METHODS: We collected epidemiological data among 234 consecutive patients consulting the outpatient sarcoidosis clinic during a two-year time period. We manually explored the electronic patient file for data retrieval. RESULTS: Out of the 234 patients, 140 are male (60%) and 94 are female (40%) patients. Forced vital capacity showed a median decline of 2% during follow-up, whereas median diffusion capacity increased with 4% over the same period of time. Within our study cohort, we observed a preponderance in employment as construction workers (14%), the chemical industry (6%) and in the metal processing industry (6%). CONCLUSION: The current study reports on epidemiological findings among the largest cohort of sarcoidosis patients in Belgium published to date.Graphical abstract [Figure: see text].

Associations between occupational and environmental exposures and organ involvement in sarcoidosis: a retrospective case-case analysis.

BACKGROUND: Sarcoidosis most commonly affects lungs and intrathoracic lymph nodes, but any other organ can be involved. In epidemiological studies, many occupational and environmental exposures have been linked to sarcoidosis but their relationship with the disease phenotype has barely been studied. OBJECTIVE: To investigate how occupational and environmental exposures prior to diagnosis relate to organ involvement in patients with sarcoidosis METHODS: We retrospectively studied patients seen at a sarcoidosis clinic between 2017 and 2020. Patients were included if they had a clinical presentation consistent with sarcoidosis and histologically confirmed epithelioid granulomas or had Löfgren syndrome. In a case-case analysis using multivariable logistic regression we calculated odds ratios (OR) of prespecified exposure categories (based on expert ascertainment) for cases with a given organ involvement versus cases without this organ involvement. RESULTS: We included 238 sarcoidosis patients. Sarcoidosis limited to pulmonary involvement was associated with exposure to inorganic dust prior to diagnosis (OR 2.11; 95% confidence interval [CI] 1.11-4.17). Patients with liver involvement had higher odds of contact with livestock (OR 3.68; 95% CI 0.91-12.7) or having jobs with close human contact (OR 4.33; 95% CI 1.57-11.3) than patients without liver involvement. Similar associations were found for splenic involvement (livestock: OR 4.94, 95% CI 1.46-16.1; close human contact: OR 3.78; 95% CI 1.47-9.46). Cardiac sarcoidosis was associated with exposure to reactive chemicals (OR 5.08; 95% CI 1.28-19.2) or livestock (OR 9.86; 95% CI 1.95-49.0). Active smokers had more ocular sarcoidosis (OR 3.26; 95% CI 1.33-7.79). CONCLUSIONS: Our study indicates that, in sarcoidosis patients, different exposures might be related to different organ involvements-hereby providing support for the hypothesis that sarcoidosis has more than one cause, each of which may promote a different disease phenotype.