The impact of perfluoroalkyl substances on the clinical manifestations of primary Sjögren syndrome

Abstract Background: The impact of environmental factors on genetically susceptible individuals constitutes a fundamental link in the pathogenesis of primary Sjögren Syndrome (pSS). Perfluoroalkyl substances (PFASs) are a class of synthetic organic fluorine chemicals that have been extensively manufactured and widely utilized over the past six decades, and they have also been identified as significant pollutants with adverse effects on human health. The impact of fluoride on the development of primary Sjögren's syndrome (pSS) remains uncertain. This study aims to investigate the correlation between common fluoride exposure and clinical manifestations of pSS. Results: We designed a population-based case-control study in China and evaluated the association. A cohort of 136 patients with SS and 148 health controls in Second Affiliated Hospital of Zhejiang University School of Medicine were investigated. There were 4 male patients and 132 female patients in the pSS cohort. The concentrations of perfluoroundecanoate (PFUdA) in the pSS group exhibited statistically higher levels compared to those in the healthy control group. The concentration of perfluorononanoate (PFNA) was significantly lower in patients with leucopenia and thrombocytopenia compared to those without this condition. The serum levels of PFNA and perfluorodecanoate (PFDA) were found to be lower in patients with a high ANA titer compared to those with a low ANA titer. The serum levels of PFNA were found to be lower in patients with Anti-SSA positive compared to those with anti-SSA negative. Conclusion: The levels of serum fluorides may be correlated with the disease activity in patients with pSS, and there might be an association between fluoride and the onset of pSS.