Zaixing Yang

Epidemiology of primary Sjögren's syndrome: a systematic review and meta-analysis

Objective Epidemiological studies of primary Sjögrens syndrome (pSS) are crucial for describing the burden to society and the public medical system and for shedding light on aetiology. Previous reports of the epidemiology of pSS show variable outcomes. We conducted a systematic review of the epidemiology of pSS to assess the prevalence rates (PRs) and incidence rates (IRs), and to investigate possible geographic variations in pSS. Methods A systematic literature search of PubMed and Embase (updated to 22 October 2013) was performed to identify all published reports on the epidemiology of pSS. The incidence and prevalence rates of pSS were summarised with IRs or PRs and 95% CIs. Results The literature search yielded 1880 related citations. Only 21 fulfilled the inclusion criteria. According to a random-effects model, the pooled IR for pSS was 6.92 (95% CI 4.98 to 8.86) per 100 000 person-years. The overall PR was 60.82 (95% CI 43.69 to 77.94) cases per 100 000 inhabitants with a slightly lower estimate of Baodong Qin is BDQ, Jiaqi Wang is JQW, Zaixing Yang is ZXY, Renqian Zhong is RQZ. 43.03 (25.74 to 60.31) cases per 100 000 inhabitants when only considering population-based studies. The female/male ratio in incidence data was 9.15 (95% CI 3.35 to 13.18). The female/male ratio in prevalence data was 10.72 (95% CI 7.35 to 15.62). The overall age of pSS patients was 56.16 years (95% CI 52.54 to 59.78). Conclusions Incidence and prevalence rates of pSS vary widely around the world. The results help us better understand the global epidemiology of pSS. Large population-based studies combining meticulous case-finding and case-ascertainment strategies are needed.

Primary Sjögren's syndrome and malignancy risk: a systematic review and meta-analysis

Objective To investigate the association between primary Sjögrens syndrome (pSS) and the risks of malignancy including overall malignancy and site-specific malignancies through a systematic review and meta-analysis. Methods We searched Pubmed before January 2013, with a restriction to English language publications. Studies were included if they met the following criteria: (1) a cohort or observational study; (2) pSS as one of the exposure interests; (3) cancer as an outcome of interest; (4) relative risk (RR) or standardised incidence rate (SIR) with 95% CIs. We used a random or fixed effects model to calculate the pooled RR according to the heterogeneity test. Results Fourteen studies involving more than 14 523 patients with pSS were included. Compared with the general population, patients with pSS had significantly increased risks of overall cancer (pooled RR 1.53; 95% CI 1.17 to 1.88), non-Hodgkin lymphoma (NHL) (pooled RR 13.76; 95% CI 8.53 to 18.99) and thyroid cancer (pooled RR 2.58; 95% CI 1.14 to 4.03). A significant association was found in various subgroup meta-analyses for NHL but, for overall malignancy, a significant association was only found in some groups. Additionally, the number of studies exploring the association of pSS with the risk of solid malignancies was so small that we could not carry out subgroup meta-analyses. Conclusions This meta-analysis indicates that pSS is significantly associated with increased risks of overall malignancy, NHL and thyroid cancer. However, it is not yet known whether the apparent increased risk of overall malignancy in patients with pSS is due to the relatively high prevalence of NHL in that group.

Primary biliary cirrhosis and cancer risk: A systematic review and meta‐analysis

Several studies have indicated that primary biliary cirrhosis (PBC) may be associated with increased risk of some cancers, but the results are controversial. We conducted a systematic review of studies to examine the association of PBC with cancer risk by meta‐analysis. We searched the PubMed and EMBASE databases for English‐language studies published before November 2011. Studies were included if they reported relative risk estimates with 95% confidence intervals (CIs) or related data for the association between PBC and cancer risk. Approximately 16,300 PBC patients from several countries were included in this analysis. Of the 3510 titles identified, 16 publications involving 17 studies meeting the inclusion criteria were included in the meta‐analysis. Compared with the general population, PBC patients had a significantly higher risk of overall cancer (pooled rate ratio [RR], 1.55; 95% CI, 1.28‐1.83) and hepatocellular carcinoma (HCC) (pooled RR, 18.80; 95% CI, 10.81‐26.79). For stomach and pancreas cancers, the results of one study that only examined male patients with PBC indicated that PBC patients had increased risk of stomach cancer and pancreatic cancer, whereas the results of other studies of mixed‐sex patients showed no significant association. Therefore, despite inconsistent results, the meta‐analysis could not be conducted for assessing the association. PBC was not significantly associated with increased risk of other cancers. Conclusion: The present systematic review and meta‐analysis demonstrate that PBC is closely associated with a greater risk of overall cancer and HCC, but not with other cancers. The data regarding the association between PBC and risks of several cancers need to be further confirmed in future studies. (HEPATOLOGY 2012)

Body mass index and the risk of rheumatoid arthritis: a systematic review and dose-response meta-analysis.

IntroductionThe evidence from published studies on the association between obesity and rheumatoid arthritis has been contradictory. To clarify the association between obesity and rheumatoid arthritis, we conducted a systematic review and dose-response meta-analysis to assess the relationship between body mass index and rheumatoid arthritis risk.MethodsA systematic literature search of PubMed and Embase (up to 12 July 2014) was performed to identify all eligible published reports. The pooled relative risk results with corresponding 95% confidence intervals of rheumatoid arthritis development were estimated using a random-effects model.ResultsEleven eligible related citations fulfilled the inclusion criteria and were included in the study. Compared with individuals with a body mass index under 30, obese individuals showed an association with a significantly increased risk of rheumatoid arthritis (relative risk = 1.25, 95% confidence interval: 1.07 to 1.45, Pheterogeneity <0.01, I2 = 63%). Compared to normal weight subjects, the pooled relative risks for rheumatoid arthritis were 1.31 (1.12 to 1.53) and 1.15 (1.03 to 1.29) for the categories of obese and overweight, respectively. In the dose-response analysis, there was evidence of a nonlinear association (Pnonlinear = 0.005) and the estimated summary relative risk for a 5-unit increment was 1.03 (95% confidence interval: 1.01 to 1.05, Pheterogeneity = 0.001, I2 = 70.0%).ConclusionsAn increase in body mass index can contribute to a higher risk for rheumatoid arthritis development. However, the finding also highlights the need for research on the association between body mass index and rheumatoid arthritis risk with adjustment for more confounding factors.

Association of increased serum IL-33 levels with clinical and laboratory characteristics of systemic lupus erythematosus in Chinese population

Systemic lupus erythematosus (SLE) is an autoimmune disease characterized by abnormal production of autoantibodies and proinflammatory cytokines. Although interleukin-33 (IL-33), a novel number of the IL-1 family, has been reported to have proinflammatory effects, the association of IL-33 with SLE has remained unknown. The aim of this study was to examine whether the serum IL-33 level is associated with SLE. A total of 70 patients with SLE were recruited. Sera from these patients were obtained at their visit and were compared to sera from 40 healthy controls or 28 patients with rheumatoid arthritis (RA) for IL-33 level. Furthermore, blood samples from patients with SLE were determined for various SLE-related laboratory variables, including blood routine, complements, erythrocyte sedimentation rate (ESR) and C-reactive protein (CRP) and some autoantibodies. Serum IL-33 level was significantly increased in patients with SLE, compared with healthy controls, but was lower than that with RA. In patients with SLE, most clinical and laboratory characteristics did not correlate with serum IL-33 levels, with exceptions of thrombocytopenia, erythrocytopenia, anti-SSB antibody, ESR, CRP and IgA. By Spearman’s correlation coefficient, patients with SLE showed close correlation of IL-33 with ESR, CRP and IgA, and by multivariate logistic regressions, patients with SLE showed significantly independent association of IL-33 with thrombocytopenia, erythrocytopenia and anti-SSB antibody. Our results suggest that IL-33 may play a role in acute phase of SLE, but it was not associated with course of the disease. Moreover, IL-33 may exert biologic effects on erythrocytes and platelets or their precursors in SLE.

Increased expression of Toll-like receptor 4 in peripheral blood leucocytes and serum levels of some cytokines in patients with ankylosing spondylitis

Toll‐like receptor 4 (TLR4) is a member of the Toll‐like receptor family, which can bridge innate and adaptive immune responses. Activation of the TLR4 signalling pathway may induce the release of proinflammatory cytokines such as tumour necrosis factor (TNF)‐α and interleukin (IL)‐12, which was considered to play an important role in pathogenesis of immune‐mediated diseases. Ankylosing spondylitis (AS) is an immune‐mediated disease whose aetiology remains unknown. The aim of the study was to investigate the expression of TLR4 and serum TNF‐α, IL‐12 and soluble tumour necrosis factor‐related apoptosis‐inducing ligand (sTRAIL) level in AS patients. The results indicated that TLR4 protein and mRNA levels were significantly higher in AS patients than in healthy controls; however, there was no significant difference between human leucocyte antigen (HLA)‐B27‐positive and ‐negative AS patients, as well as serum levels of TNF‐α, IL‐12 and sTRAIL. In addition, in HLA‐B27‐positive AS patients, TLR4 level showed close associations with the cytokines and laboratory parameters of disease activity [erythrocyte sedimentation rate (ESR) and plasma C‐reactive protein (CRP)], respectively. Similarly, the strong associations between the cytokines or between IL‐12 and ESR or CRP were observed in HLA‐B27‐positive AS patients. Interestingly, in HLA‐B27‐positive AS patients, TNF‐α correlated significantly with ESR, but did not with CRP. In contrast, sTRAIL correlated with CRP, but did not with ESR. Among HLA‐B27‐negative patients, no close correlation was found. In our study, it was suggested that the abnormal activation of TLR4 signalling and serum TNF‐α, IL‐12 and sTRAIL may play a key role in the development and progression of AS, which may be dependent on the status of HLA‐B27 antigen.

Neutrophil to lymphocyte ratio (NLR) and platelet to lymphocyte ratio (PLR) were useful markers in assessment of inflammatory response and disease activity in SLE patients

Abstract Objective: Although there have been extensive investigations on neutrophil to lymphocyte ratio (NLR), platelet to lymphocyte ratio (PLR) and mean platelet volume (MPV) in many diseases, their roles in systemic lupus erythematosus (SLE) remain unclear. The purpose of the present study was to evaluate NLR, PLR, and MPV levels in adult SLE patients and explore their clinical significance. Methods: A retrospective study involving 154 adult SLE patients and 151 healthy controls was performed. All clinical characteristics of the SLE patients were extracted from their medical records. NLR, PLR, and MPV levels between SLE patients and healthy controls were compared, and correlations between these indexes and clinical characteristics were analyzed. Results: Increased NLR, PLR, and MPV were observed in SLE patients. NLR was positively correlated with C-reaction protein (r = 0.509, p < 0.01), erythrocyte sedimentation rate (r = 0.610, p < 0.01), and SLE Disease Activity Index (SLEDAI) scores (r = 0.471, p < 0.01). PLR was positively correlated with SLEDAI scores (r = 0.44, p < 0.01). SLE patients with nephritis had higher NLR and PLR levels than those without nephritis (p < 0.01, p = 0.03). In addition, an NLR level of 2.065 was determined as predictive cut-off value of SLE (sensitivity 74.7%, specificity 77.5%, AUC = 0.828). Multiple regression analysis suggested that NLR was independently associated with SLE disease activity. Conclusions: NLR and PLR could reflect inflammatory response and disease activity in SLE patients.

Polymyositis/dermatomyositis and malignancy risk: a metaanalysis study.

Objective. To investigate the association between polymyositis (PM)/dermatomyositis (DM) and risks of malignancy. Methods. We searched Pubmed for articles dated before August 16, 2013. Studies were included if they met the following criteria: (1) a cohort or observational study; (2) PM or DM as one of the exposures of interest; (3) cancer as an outcome of interest; and (4) the rate ratio (RR) or standardized incidence ratio (SIR) were available with their 95% CI. We used random-effects or fixed-effects models to calculate the pooled RR according to the heterogeneity test. Results. Twenty publications were included. Compared with the general population, the pooled RR for patients with PM, DM, and PM/DM were 1.62 (95% CI 1.19–2.04), 5.50 (4.31–6.70), and 4.07 (3.02–5.12), respectively. The increased risks were more significant in patients within the first year of myositis diagnosis, male patients, and population-based studies (for DM). A significant association was also found between PM or DM and most site-specific malignancies. However, both PM and DM were not associated with stomach and prostate cancers. Significant heterogeneity was found between studies on association between PM/DM and overall malignancy, but not between PM/DM and the majority of site-specific malignancies, suggesting that that inherent malignancy difference may be a major source of heterogeneity. Conclusion. The present metaanalysis indicates that PM and DM are significantly associated with increased risks of overall malignancy and most site-specific malignancies. The number of studies on association between PM or DM and some malignancies is too small to draw a firm conclusion. Accordingly, more research is needed for these malignancies.

Analysis of altered microRNA expression profiles in peripheral blood mononuclear cells from patients with primary biliary cirrhosis

MicroRNA, as an important regulator of gene expression, has been found to be associated with several diseases. MicroRNA expression profiles have been identified in several autoimmune diseases, such as rheumatoid arthritis, systemic lupus erythematosus, and multiple sclerosis. However, the expression profile in peripheral blood mononuclear cells (PBMCs) from primary biliary cirrhosis (PBC) patients and the role of microRNA in PBC remained unclear. The present study aimed to explore abnormal microRNA regulation in PBC.

Smoking, family history and urinary tract infection are associated with primary biliary cirrhosis: A meta‐analysis

Aim:  This meta‐analysis was conducted to provide more precise evidence for association between primary biliary cirrhosis (PBC) and smoking and some other factors.