Association of proton-pump inhibitor use with adverse health outcomes: A systematic umbrella review of meta-analyses of cohort studies and randomised controlled trials.

AIMS: The aim was to perform an umbrella review to summarise the existing evidence on proton-pump inhibitor (PPI) use and adverse outcomes and to grade the certainty of evidence. METHODS: Electronic databases were searched up to July 2021 for meta-analyses of cohort studies and/or randomised controlled trials (RCTs). Summary effect sizes from a random-effects model, between-study heterogeneity, 95% prediction interval, small-study effect, excess significance and credibility ceilings were devised to classify the credibility of evidence from meta-analyses of cohort studies, whereas the GRADE approach was used for meta-analyses of RCTs. RESULTS: In meta-analyses of cohort studies, 52 of the 91 examined associations were statistically significant (P ≤ .05). Convincing evidence emerged from main analysis for the association between PPI use and risk of all-site fracture and chronic kidney disease in the elderly population. However, none of these associations remained supported by convincing evidence after sensitivity analyses. The use of PPI is also associated with an increased risk of mortality due to COVID-19 infection and other related adverse outcomes, but the quality of evidence was weak. In meta-analyses of RCTs, 38 of the 63 examined associations were statistically significant. However, no associations were supported by high or moderate-quality evidence. CONCLUSION: This study's findings imply that most putative adverse outcomes associated with PPI use may not be supported by high-quality evidence and are likely to have been affected by underlying confounding factors. Future research is needed to confirm the causal association between PPI use and risk of fracture and chronic kidney disease.

The IRF5 rs2004640 (G/T) polymorphism is not a genetic risk factor for systemic lupus erythematosus in population from south India.

Background & objectives: Genetic aberrations disrupting toll-like receptor and interferon homeostasis enhance the risk of systemic lupus erythematosus (SLE). Raised serum interferon-alpha (IFN-α) levels in SLE patients have been ascribed to polymorphism (rs2004640 G/T) in interferon regulatory factor 5 (IRF5) gene, resulting in enhanced transcript splicing. A positive association between IRF5 polymorphism and SLE risk has been reported in many populations. This study was aimed to find out frequency of IRF5 rs2004640 G/T polymorphism in patients with SLE and healthy controls and to assess its influence on susceptibility, clinical and serological characteristics of SLE. Methods: IRF5 rs2004640 (G/T) polymorphism was analyzed in 300 SLE patients and 460 age and sex matched controls by real-time PCR. Results: The IRF5 rs2004640 (G/T) polymorphism did not confer risk of SLE or influence clinical or serological phenotype. However, the mutant allele conferred a borderline risk to develop thrombocytopenia (odds ratio: 2.05, 95% confidence interval: 0.97-4.3, P=0.06) in patients with SLE. Interpretation & conclusions: Our study revealed that the IRF5 rs2004640 polymorphism was not a risk factor for SLE in population from south India. It may, however, be a useful genetic marker for thrombocytopenia in SLE patients. Although we could not demonstrate susceptibility toward lupus in the presence of IRF5 rs2004640 (G/T) polymorphism, further exploration of the genetic variability of IRF5 may help uncover its pathogenic role in Indian SLE patients.

Mannose-binding lectin (MBL) codon 54 (rs1800450) polymorphism predisposes towards medium vessel vasculitis in patients with systemic lupus erythematosus.

Systemic lupus erythematosus (SLE) is a systemic autoimmune disease with multiple etiological factors. Mannose-binding lectin (MBL) plays a key role in innate immunity by activating antibody-independent lectin complement pathway, opsonisation, phagocytosis, and immune complex (IC) clearance. Genetic polymorphisms in the promoter and coding regions of MBL gene affect the circulatory levels and biological activity of MBL. Defects in MBL can lead to defective opsonisation and, hence, hamper clearance of apoptotic debris, the persistence of which can drive autoantibody formation in lupus. The exon1 variants at codon 52, 54, and 57 have been reported to augment the risk of SLE in different ethnic populations. Three hundred South Indian Tamil patients with SLE and 460 age-, sex-, and ethnicity-matched controls were genotyped for three polymorphisms at codon 52, 54, and 57 in exon1 of MBL gene by Taqman real-time PCR. The three polymorphisms in exon1 of MBL were observed not to confer risk of developing SLE. However, MBL codon 54 rs1800450 polymorphism was associated with the development of medium vessel vasculitis and gangrene (OR-2.29, CI 95% 1.08-4.83, p = 0.02), whereas, the ancestral allele G conferred protection (OR-0.44, CI 95% 0.21-0.93, p = 0.02). Genetic variants in the exon1 of MBL gene per se are not risk factors for SLE in South Indian Tamils. However, the association of codon 54 (rs1800450) with medium vessel vasculitis suggests that it may be a genetic modifier of clinical phenotype in SLE.

Multidrug resistance 1 (MDR1) 3435C>T gene polymorphism influences the clinical phenotype and methotrexate-induced adverse events in South Indian Tamil rheumatoid arthritis.

PURPOSE: Rheumatoid arthritis (RA) is a chronic systemic autoimmune disease primarily targeting the synovial joints causing joint damage and significant functional impairment. Methotrexate (MTX) remains the mainstay for the treatment of RA, and approximately 10-30% of the patients fail to attain remission because of inefficacy of the drug or due to development of adverse events. Multidrug resistance 1 (MDR1) gene encodes for permeable glycoprotein (P-gp) which is an integral membrane protein for the transport of chemotherapeutic agents, immunosuppressive drugs etc. MDR1 3435C>T results in a wobble mutation in exon 26 but is associated with altered P-gp expression and reduced P-gp function. The present study was carried out to find the role of MDR1 3435C>T gene polymorphism with clinical phenotype, treatment response, and MTX adverse events in 336 RA and 329 healthy controls of South Indian Tamil ethnicity. METHODS: MDR1 3435C>T gene polymorphism was analyzed by TaqMan 5' nuclease assay. RESULTS: We found MDR1 3435T allele as a risk allele for contributing to high EULAR disease activity [p = 0.02, OR 1.50, 95% CI (1.06-2.13)]. Also, MDR1 3435CT genotype was associated with deforming disease [p = 0.02, OR 1.79, 95% CI (1.11-2.88)]. However, this SNP did not influence the MTX treatment response in these patients. MDR1 3435CT genotype was associated with MTX-induced adverse events [p = 0.01, OR 2.01, 95% CI (1.15-3.52)], and the 3435 TT genotype remained protective for the development of adverse events [p = 0.009, OR 0.40, 95% CI (0.21-0.78)]. Also, the heterozygous 3435 CT genotype was associated with gastrointestinal events [p = 0.02, OR 3.62, 95% CI (1.25-10.47)], and CT genotype remained protective in patients developing infection [p = 0.002, OR 0.05, 95% CI (0.006-0.460)]. CONCLUSION: MDR1 3435C>T gene polymorphism influences the clinical phenotype and adverse events to MTX in the South Indian cohort of patients with RA.

Susceptibility to SLE in South Indian Tamils may be influenced by genetic selection pressure on TLR2 and TLR9 genes.

INTRODUCTION: Systemic lupus erythematosus (SLE) is a multisystem autoimmune disorder with complex etiology. Genetics plays an important role in lupus pathogenesis through its influence on clinical and autoantibody phenotype of the disease. Toll like receptors (TLR) recognize molecular patterns of pathogens and activate the innate immune system. Their ability to identify nucleic acids makes them suitable candidates for investigation of their role in lupus pathogenesis. Hence, this study was carried out to analyze the G to A and C to T transitions in TLR2 and TLR9 genes respectively and to test their association with lupus susceptibility, clinical and autoantibody phenotypes in South Indian Tamils. METHOD: Three hundred SLE patients fulfilling ACR 2012 criteria for SLE and 460 age, sex similar, ethnicity matched controls were recruited as cases and controls. TLR2 (R753Q) and TLR9 (-1237C/T) polymorphisms were analyzed by real time PCR. RESULTS: The TLR2 gene remained monomorphic in patients and controls, the frequency of the homozygous wild type allele being 100% and 99.6% respectively. Hence, it did not confer susceptibility to SLE. The more frequent T allele of TLR9 gene conferred a significant risk to develop SLE (p=0.011, OR 1.69, 95% CI 1.1-2.6). Both the polymorphisms did not influence clinical or autoantibody phenotype of the disease. CONCLUSION: Prevailing endemic infections in the Indian subcontinent may have exerted a selection pressure resulting in TLR2 gene remaining monomorphic and the TLR9 adapting to a mutation for its increased expression. These may have an additive effect in the presence of other genetic and environmental risk factors to confer susceptibility to SLE in South Indian Tamils.

Anaplastic large cell lymphoma in a patient with systemic onset juvenile arthritis: case report and review of literature.

The association of malignancy with autoimmune rheumatic diseases has been a subject of investigation. It has been shown that there is increased risk of malignancies, mainly non-Hodgkin lymphoma, in patients with autoimmune disorders. There is scarcity of data about malignancy in juvenile idiopathic arthritis (JIA). We report the occurrence of anaplastic large cell lymphoma in a patient with systemic onset juvenile idiopathic arthritis treated with low dose methotrexate (MTX). A relationship between MTX treatment and the occurrence of lymphoma in autoimmune diseases has been suggested. The hypothesis that MTX has a role in the aetiology of lymphoproliferative disorders is supported by the observation of spontaneous remission of lymphoma in few cases on cessation of MTX therapy. However, systemic onset juvenile idiopathic arthritis patients receiving MTX must be periodically examined for the development of lymphoproliferative disorder especially if the disease is difficult to control or patient develop new symptoms on therapy.