Exposure to air pollution as an environmental determinant of how Sjögren's disease is expressed at diagnosis.

OBJECTIVES: To analyse how the potential exposure to air pollutants can influence the key components at the time of diagnosis of Sjögren's phenotype (epidemiological profile, sicca symptoms, and systemic disease). METHODS: For the present study, the following variables were selected for harmonization and refinement: age, sex, country, fulfilment of 2002/2016 criteria items, dry eyes, dry mouth, and overall ESSDAI score. Air pollution indexes per country were defined according to the OECD (1990-2021), including emission data of nitrogen and sulphur oxides (NO/SO), particulate matter (PM2.5 and 1.0), carbon monoxide (CO) and volatile organic compounds (VOC) calculated per unit of GDP, Kg per 1000 USD. RESULTS: The results of the chi-square tests of independence for each air pollutant with the frequency of dry eyes at diagnosis showed that, except for one, all variables exhibited p-values <0.0001. The most pronounced disparities emerged in the dry eye prevalence among individuals inhabiting countries with the highest NO/SO exposure, a surge of 4.61 percentage points compared to other countries, followed by CO (3.59 points), non-methane (3.32 points), PM2.5 (3.30 points), and PM1.0 (1.60 points) exposures. Concerning dry mouth, individuals residing in countries with worse NO/SO exposures exhibited a heightened frequency of dry mouth by 2.05 percentage points (p<0.0001), followed by non-methane exposure (1.21 percentage points increase, p=0.007). Individuals inhabiting countries with the worst NO/SO, CO, and PM2.5 pollution levels had a higher mean global ESSDAI score than those in lower-risk nations (all p-values <0.0001). When systemic disease was stratified according to DAS into low, moderate, and high systemic activity levels, a heightened proportion of individuals manifesting moderate/severe systemic activity was observed in countries with worse exposures to NO/SO, CO, and PM2.5 pollutant levels. CONCLUSIONS: For the first time, we suggest that pollution levels could influence how SjD appears at diagnosis in a large international cohort of patients. The most notable relationships were found between symptoms (dryness and general body symptoms) and NO/SO, CO, and PM2.5 levels.

Influence of exposure to climate-related hazards in the phenotypic expression of primary Sjögren's syndrome.

OBJECTIVES: To analyse how the key components at the time of diagnosis of the Sjögren's phenotype (epidemiological profile, sicca symptoms, and systemic disease) can be influenced by the potential exposure to climate-related natural hazards. METHODS: For the present study, the following variables were selected for harmonisation and refinement: age, sex, country, fulfilment of 2002/2016 criteria items, dry eyes, dry mouth, and overall ESSDAI score. Climate-related hazards per country were defined according to the OECD and included seven climate-related hazard types: extreme temperature, extreme precipitation, drought, wildfire, wind threats, river flooding, and coastal flooding. Climatic variables were defined as dichotomous variables according to whether each country is ranked among the ten countries with the most significant exposure. RESULTS: After applying data-cleaning techniques and excluding people from countries not included in the OECD climate rankings, the database study analysed 16,042 patients from 23 countries. The disease was diagnosed between 1 and 3 years earlier in people living in countries included among the top 10 worst exposed to extreme precipitation, wildfire, wind threats, river flooding, and coastal flooding. A lower frequency of dry eyes was observed in people living in countries exposed to wind threats, river flooding, and coastal flooding, with a level of statistical association being classified as strong (p<0.0001 for the three variables). The frequency of dry mouth was significantly lower in people living in countries exposed to river flooding (p<0.0001) and coastal flooding (p<0.0001). People living in countries included in the worse climate scenarios for extreme temperature (p<0.0001) and river flooding (p<0.0001) showed a higher mean ESSDAI score in comparison with people living in no-risk countries. In contrast, those living in countries exposed to worse climate scenarios for wind threats (p<0.0001) and coastal flooding (p<0.0001) showed a lower mean ESSDAI score in comparison with people living in no-risk countries. CONCLUSIONS: Local exposure to extreme climate-related hazards plays a role in modulating the presentation of Sjögren across countries concerning the age at which the disease is diagnosed, the frequency of dryness, and the degree of systemic activity.

Parotid gland swelling in primary Sjögren's syndrome: activity and other sialadenosis causes.

OBJECTIVE: To assess the prevalence of parotid gland swelling (PGS) and its association with features of SS and other causes of sialadenosis in a Latin-American cohort of primary SS. METHODS: We included 668 patients from Argentina, Brazil, Mexico and Paraguay. We retrospectively registered demographics, disease duration, oral/ocular symptoms, serology and scored the basal ESSDAI. We defined PGS as a recurrent or persistent increase of volume of any parotid glands during adulthood (self-reported and/or physical examination). We registered the presence of diabetes mellitus, dyslipidaemia, body mass index and alcohol consumption. We used logistic regression analysis reporting odds ratio (OR) and 95% CI. RESULTS: PGS was present in 242 patients (36.2%): 78 previous to SS diagnosis, 86 concomitantly, 73 during follow-up and five unknown. At the multivariate analysis, PGS was associated with RF (OR 2.47, 95% CI: 1.1, 6.5, P = 0.0001), basal articular ESSDAI domain (OR 1.63, 95% CI: 1.01, 2.6, P = 0.04) and alcohol consumption (OR 2.42, 95% CI: 1.41, 4-15). Patients with PGS during the follow-up had a higher prevalence of alcohol consumption (45.3%) compared with the remaining PGS cases (26.8%; OR 2.41 95% CI: 1.2, 4.7), or patients without parotid gland swelling (15.6%; OR 3.8 95% CI: 1.7, 8.2) in all the adjusted models. CONCLUSION: PGS generally precedes or presents concomitantly with SS diagnosis, and is related to RF and articular activity. Alcohol consumption is an additional factor in PGS, especially during follow-up. The meaning of this last finding as well as its prognostic implications remains to be elucidated and deserves further evaluation in prospective studies.

Is Sjögren's syndrome dry eye similar to dry eye caused by other etiologies? Discriminating different diseases by dry eye tests.

PURPOSE: Dry Eye Disease (DED) is part of several conditions, including Sjögren's syndrome (SS) and no single test to diagnosis DED. The present study intends to evaluate whether a set of signs and symptoms of DED can distinguish: a) SS from other non-overlapping systemic diseases related to DED; b) primary and secondary SS. METHODS: 182 consecutive patients with DED were evaluated under five groups: SS, graft-versus-host disease (GVHD), Graves' orbitopathy (GO), diabetes mellitus (DM), glaucoma under treatment with benzalkonium chloride medications (BAK). Twenty-four healthy subjects were included as control group (CG). The evaluation consisted of Ocular Surface Disease Index (OSDI), Schirmer test (ST), corneal fluorescein staining (CFS) and tear film break up time (TFBUT). Indeed, a subset of DED patients (n = 130), classified as SS1, SS2 and nonSS (NSS) by the American-European Criteria were compared. Quadratic discriminant analysis (QDA) classified the individuals based on variables collected. The area under Receiver Operating Characteristics (ROC) curve evaluated the classification performance in both comparisons. RESULTS: Comparing SS with other diseases, QDA showed that the most important variable for classification was OSDI, followed by TFBUT and CFS. Combined, these variables were able to correctly classify 62.6% of subjects in their actual group. At the discretion of the area under the ROC curve, the group with better classification was the control (97.2%), followed by DM (95.5%) and SS (92.5%). DED tests were different among the NSS, SS1 and SS2 groups. The analysis revealed that the combined tests correctly classified 54.6% of the patients in their groups. The area under the ROC curve better classified NSS (79.5%), followed by SS2 (74.4%) and SS1 (69.4%). CONCLUSIONS: Diseases that causes DED, and also SS1, SS2 and NSS are distinguishable conditions, however a single ocular tools was not able to detect the differences among the respective groups.