Obesity and the risk of systemic lupus erythematosus among women in the Nurses' Health Studies

Causal associations of birth body size and adult body size with systemic lupus erythematosus: a bidirectional mendelian randomization study

Objective

Body size is associated with the onset of systemic lupus erythematosus (SLE). However, the evidence for this association is inconclusive. In this study, we aimed to investigate the causal relationship between body size and SLE.

Method

We performed a bidirectional Mendelian randomization (MR) analysis that utilized summary statistics sourced from genome-wide association study (GWAS) data obtained from the IEU Open GWAS project website. The inverse variance weighting (IVW) method was used to evaluate the causality, and four additional MR methods were used to supplement the IVW results. Sensitivity analyses were performed using the Cochran's Q test, MR-Egger regression, leave-one-out analysis, and the Mendelian Randomization Pleiotropy RESidual Sum and Outlier (MR-PRESSO) global test.

Results

In the forward direction analysis, the IVW model demonstrated that birth weight (odds ratio (OR), 1.811; 95% confidence interval (CI), 1.174-2.793; p < 0.05) and adult height (OR, 1.225; 95% CI, 1.046-1.434; p < 0.05) were positively associated with SLE. Four additional MR scans were performed parallel to the IVW results. Conversely, SLE was a weak causal factor for increased height (OR, 1.010; 95% CI, 1.002-1.018; p < 0.05) using the IVW method. Heterogeneity, MR-Egger intercept, and leave-one-out analyses indicated that the results were robust. The MR-PRESSO suggested the presence of pleiotropy. Following the exclusion of instrumental variables (IVs) inducing pleiotropy, subsequent MR analysis yielded consistent results, thereby reinforcing the robustness of our findings.

Conclusion

Positive causal associations were observed between birth weight, adult height, and SLE incidence. In the reverse analysis, SLE was a weak causal factor for adult height.

Epidemiology of Sarcoidosis

Sarcoidosis is a systemic, granulomatous disease with variable presentation earning it the term "the great mimicker." The current epidemiology confirms that the disease occurs worldwide, affecting both sexes, and all races, ethnicities, and ages. To date, no causal exposure or agent has been identified. The organ systems most frequently affected by sarcoidosis are also those with greatest exposure to the natural world suggesting environmental and lifestyle contributions to the disease. These include particulate matter, microorganisms, nicotine, and obesity. In this article, we review the epidemiology of sarcoidosis and discuss these non-genetic risk factors in the hope of providing important insight into sarcoidosis and stimulating future research.

Autoimmune Disorders Associated With Surgical Remission of Cushing's Disease : A Cohort Study

BACKGROUND

Glucocorticoids suppress inflammation. Autoimmune disease may occur after remission of Cushing's disease (CD). However, the development of autoimmune disease in this context is not well described.

OBJECTIVE

To determine 1) the incidence of autoimmune disease in patients with CD after surgical remission compared with patients with nonfunctioning pituitary adenomas (NFPAs) and 2) the clinical presentation of and risk factors for development of autoimmune disease in CD after remission.

DESIGN

Retrospective matched cohort analysis.

SETTING

Academic medical center/pituitary center.

PATIENTS

Patients with CD with surgical remission and surgically treated NFPA.

MEASUREMENTS

Cumulative incidence of new-onset autoimmune disease at 3 years after surgery. Assessment for hypercortisolemia included late-night salivary cortisol levels, 24-hour urine free cortisol (UFC) ratio (UFC value divided by the upper limit of the normal range for the assay), and dexamethasone suppression tests.

RESULTS

Cumulative incidence of new-onset autoimmune disease at 3 years after surgery was higher in patients with CD (10.4% [95% CI, 5.7% to 15.1%]) than in those with NFPAs (1.6% [CI, 0% to 4.6%]) (hazard ratio, 7.80 [CI, 2.88 to 21.10]). Patients with CD showed higher prevalence of postoperative adrenal insufficiency (93.8% vs. 16.5%) and lower postoperative nadir serum cortisol levels (63.8 vs. 282.3 nmol/L) than patients with NFPAs. Compared with patients with CD without autoimmune disease, those who developed autoimmune disease had a lower preoperative 24-hour UFC ratio (2.7 vs. 6.3) and a higher prevalence of family history of autoimmune disease (41.2% vs. 20.9%).

LIMITATION

The small sample of patients with autoimmune disease limited identification of independent risk factors.

CONCLUSION

Patients achieving surgical remission of CD have higher incidence of autoimmune disease than age- and sex-matched patients with NFPAs. Family history of autoimmune disease is a potential risk factor. Adrenal insufficiency may be a trigger.

PRIMARY FUNDING SOURCE

Recordati Rare Diseases Inc.

Dietary tryptophan and genetic susceptibility expand gut microbiota that promote systemic autoimmune activation

Tryptophan modulates disease activity and the composition of microbiota in the B6.Sle1.Sle2.Sle3 (TC) mouse model of lupus. To directly test the effect of tryptophan on the gut microbiome, we transplanted fecal samples from TC and B6 control mice into germ-free or antibiotic-treated non-autoimmune B6 mice that were fed with a high or low tryptophan diet. The recipient mice with TC microbiota and high tryptophan diet had higher levels of immune activation, autoantibody production and intestinal inflammation. A bloom of Ruminococcus gnavus (Rg), a bacterium associated with disease flares in lupus patients, only emerged in the recipients of TC microbiota fed with high tryptophan. Rg depletion in TC mice decreased autoantibody production and increased the frequency of regulatory T cells. Conversely, TC mice colonized with Rg showed higher autoimmune activation. Overall, these results suggest that the interplay of genetic and tryptophan can influence the pathogenesis of lupus through the gut microbiota.

Patients with systemic lupus erythematosus who are underweight have distinct disease characteristics

OBJECTIVE

This study aimed to detail the disease characteristics of systemic lupus erythematosus (SLE) in individuals who are underweight and assess whether underweight status is associated with SLE disease activity.

METHODS

This was a retrospective cohort study involving 218 patients newly diagnosed with SLE. Patients were categorized as underweight (body mass index [BMI] <18.5 kg/m2) or not underweight (BMI ≥18.5 kg/m2). We reviewed disease characteristics including the SLE Disease Activity Index 2000 (SLEDAI-2K) at diagnosis. High disease activity was defined as SLEDAI-2K ≥10. Disease characteristics were compared between those who were underweight and not underweight. We used multivariable logistic regression analysis to determine whether underweight status is associated with high disease activity.

RESULTS

Out of the 218 patients, 35 (16.1%) were underweight and 183 (83.9%) were not. Underweight patients had less renal involvement (5.7% vs 20.2%, p = .040), lower C-reactive protein levels (1.0 [0.3-2.3] mg/L vs 1.2 [0.8-5.0] mg/L, p = .028), and lower SLEDAI-2K scores (6.7 ± 4.6 vs 9.1 ± 5.7, p = .009), and were less likely to be at high disease activity status (22.9% vs 42.6%, p = .028), compared with those who were not underweight. Following adjustment for multiple covariates, being underweight was inversely associated with high disease activity status (adjusted odds ratio = 0.38, 95% confidence interval = 0.16 to 0.92, p = .031).

CONCLUSION

Patients with SLE who were underweight showed less renal involvement and lower SLEDAI-2K scores compared with those who were not underweight. Moreover, those with SLE who were underweight had a 60% lower risk of exhibiting high disease activity.

Impact of prior bariatric surgery on outcomes of hospitalized patients with systemic lupus erythematosus: a propensity score-matched analysis of the U.S. nationwide inpatient sample

BACKGROUND

Systemic lupus erythematosus (SLE) is an autoimmune disease that primarily affects young women, has many different manifestations, and the disease severity can wax and wane.

OBJECTIVES

This study aims to determine the association between prior bariatric surgery and SLE outcomes.

SETTING

A population-based, retrospective study using data from the U.S. Nationwide Inpatient Sample (NIS) database between 2005 and 2018.

METHODS

Data of hospitalized patients with SLE and morbid obesity were extracted. Exclusion criteria were age <18 years and missing information on mortality. Patients were separated into 2 groups: with or without prior bariatric surgery. One: 4 propensity score matching (PSM) were performed to balance the characteristics between the groups. Associations between prior bariatric surgery and inpatient outcomes were determined by logistic regressions.

RESULTS

A total of 38,286 hospitalized patients with SLE and morbid obesity were identified. After exclusions and PSM, there remained 9050 subjects in the study sample (with prior bariatric surgery: 1810; without prior bariatric surgery: 7240), representing 44,952 U.S. inpatients. After adjusting for confounders in multivariable analysis, prior bariatric surgery was significantly associated with lower odds for prolonged length of stay (LOS), unfavorable discharge, and SLE-related complications. Specifically, prior bariatric surgery was significantly associated with lower risks of acute myocardial infarction (AMI)/stroke (aOR = .44, 95% CI: .30-.65), venous thromboembolism (VTE) (aOR = .74, 95% CI: .57-.96), pneumonia (aOR = .60, 95% CI: .47-.76), sepsis (aOR = .62, 95% CI: .51-.75), acute and chronic glomerulonephritis (aOR = .53, 95% CI: .38-.76), acute kidney injury (AKI) (aOR = .64, 95% CI: .52-.77), and anemia (aOR = .77, 95% CI: .68-.87).

CONCLUSIONS

Prior bariatric surgery is associated with favorable in-hospital outcomes in hospitalized patients with SLE and decreased likelihood for several SLE-related complications.

Sarcoidosis and its relation to other immune-mediated diseases: Epidemiological insights

Several epidemiological studies show a co-occurrence of sarcoidosis with other immune-mediated diseases (IMD). There are many similarities between sarcoidosis and IMDs in their geographical distribution and risk factors. Understanding these similarities and identifying the differences can help us to better understand sarcoidosis and put it into context with other IMDs. In this review, we present the current knowledge about the overlap between sarcoidosis and other IMDs derived from epidemiological studies. Epidemiologic methods utilize study design and statistical analysis to describe the patterns in data and, ideally, identify causal relationships between an exposure and a health outcome. We discuss how study design and analysis may affect the interpretation of epidemiological studies on this topic and highlight some theories that attempt to explain the relation between sarcoidosis and other IMDs.

Autoimmune Connective Tissue Diseases: Systemic Lupus Erythematosus and Rheumatoid Arthritis

Systemic lupus erythematosus and rheumatoid arthritis are just 2 of several autoimmune connective tissue diseases that are primarily chronic in nature but can present to the emergency department by virtue of an acute exacerbation of disease. Beyond an acute exacerbation of disease, their predilection for invading multiple organ systems lends itself to the potential for patients presenting to the emergency department with either a single or isolated symptom or a myriad of signs and/or symptoms indicative of a degree of disease complexity and severity that warrant timely recognition and resuscitation.

Relationship between neutrophil gelatinase-associated lipocalin levels and disease parameters including clinicopathological parameters and various cytokine levels in systemic lupus erythematosus

Urine neutrophil gelatinase-associated lipocalin (NGAL) is a marker of acute kidney injury and indicates tubular damage. Lupus nephritis-associated renal injury is characterized by damage to the glomeruli and tubular portions of the kidneys. Therefore, NGAL concentrations are expected to vary according to the severity of systemic lupus erythematosus (SLE). In this study, samples from (NZB × NZW) F1 mice at an advanced stage of SLE were used to determine whether serum and urine NGAL concentrations or the urine NGAL:creatinine (uNGAL/C) ratio can be used to reflect diet, disease state, and treatment efficacy. Additionally, the relationship between the levels of NGAL and various cytokines in the serum in SLE was evaluated. Mice were divided into the following four groups (n=15): CN, chow diet and no treatment (saline; intraperitonially injected [i.p.]; 200 μL/day); CP, chow diet and methylprednisolone (i.p.; 5 mg/kg/day); HN, high-fat diet and no treatment (saline [i.p.]; 200 μL/day); and HP, high-fat diet and methylprednisolone treatment (i.p.; 5 mg/kg/day) every day from 6 to 42 weeks of age. The serum and urine NGAL levels and uNGAL/C values were significantly lower in the CP group than those in the CN group. Further, serum NGAL concentration demonstrated a strong positive correlation with urine NGAL levels, uNGAL/C, urine protein concentrations, urine protein:creatinine ratio, and the expression of several cytokines associated with SLE pathogenesis (interleukin [IL]-6, tumor necrosis factor [TNF]-α, and interferon-induced protein [IP]-10). These results suggest that NGAL has a strong positive correlation with the clinicopathological parameters and several key cytokines in SLE.

Differential impact of environmental factors on systemic and localized autoimmunity

The influence of environmental factors on the development of autoimmune disease is being broadly investigated to better understand the multifactorial nature of autoimmune pathogenesis and to identify potential areas of intervention. Areas of particular interest include the influence of lifestyle, nutrition, and vitamin deficiencies on autoimmunity and chronic inflammation. In this review, we discuss how particular lifestyles and dietary patterns may contribute to or modulate autoimmunity. We explored this concept through a spectrum of several autoimmune diseases including Multiple Sclerosis (MS), Systemic Lupus Erythematosus (SLE) and Alopecia Areata (AA) affecting the central nervous system, whole body, and the hair follicles, respectively. A clear commonality between the autoimmune conditions of interest here is low Vitamin D, a well-researched hormone in the context of autoimmunity with pleiotropic immunomodulatory and anti-inflammatory effects. While low levels are often correlated with disease activity and progression in MS and AA, the relationship is less clear in SLE. Despite strong associations with autoimmunity, we lack conclusive evidence which elucidates its role in contributing to pathogenesis or simply as a result of chronic inflammation. In a similar vein, other vitamins impacting the development and course of these diseases are explored in this review, and overall diet and lifestyle. Recent work exploring the effects of dietary interventions on MS showed that a balanced diet was linked to improvement in clinical parameters, comorbid conditions, and overall quality of life for patients. In patients with MS, SLE and AA, certain diets and supplements are linked to lower incidence and improved symptoms. Conversely, obesity during adolescence was linked with higher incidence of MS while in SLE it was associated with organ damage. Autoimmunity is thought to emerge from the complex interplay between environmental factors and genetic background. Although the scope of this review focuses on environmental factors, it is imperative to elaborate the interaction between genetic susceptibility and environment due to the multifactorial origin of these disease. Here, we offer a comprehensive review about the influence of recent environmental and lifestyle factors on these autoimmune diseases and potential translation into therapeutic interventions.

Autoimmune pre-disease

Approximately 5% of the world-wide population is affected by autoimmune diseases. Overall, autoimmune diseases are still difficult to treat, impose a high burden on patients, and have a significant economic impact. Like other complex diseases, e.g., cancer, autoimmune diseases develop over several years. Decisive steps in the development of autoimmune diseases are (i) the development of autoantigen-specific lymphocytes and (often) autoantibodies and (ii) potentially clinical disease manifestation at a later stage. However, not all healthy individuals with autoantibodies develop disease manifestations. Identifying autoantibody-positive healthy individuals and monitoring and inhibiting their switch to inflammatory autoimmune disease conditions are currently in their infancy. The switch from harmless to inflammatory autoantigen-specific T and B-cell and autoantibody responses seems to be the hallmark for the decisive factor in inflammatory autoimmune disease conditions. Accordingly, biomarkers allowing us to predict this progression would have a significant impact. Several factors, such as genetics and the environment, especially diet, smoking, exposure to pollutants, infections, stress, and shift work, might influence the progression from harmless to inflammatory autoimmune conditions. To inspire research directed at defining and ultimately targeting autoimmune predisease, here, we review published evidence underlying the progression from health to autoimmune predisease and ultimately to clinically manifest inflammatory autoimmune disease, addressing the following 3 questions: (i) what is the current status, (ii) what is missing, (iii) and what are the future perspectives for defining and modulating autoimmune predisease.

Risk prediction models for incident systemic lupus erythematosus among women in the Nurses' health study cohorts using genetics, family history, and lifestyle and environmental factors

OBJECTIVE

Systemic lupus erythematosus (SLE) is a severe multisystem autoimmune disease that predominantly affects women. Its etiology is complex and multifactorial, with several known genetic and environmental risk factors, but accurate risk prediction models are still lacking. We developed SLE risk prediction models, incorporating known genetic, lifestyle and environmental risk factors, and family history.

METHODS

We performed a nested case-control study within the Nurses' Health Study cohorts (NHS). NHS began in 1976 and enrolled 121,700 registered female nurses ages 30-55 from 11 U.S. states; NHSII began in 1989 and enrolled 116,430 registered female nurses ages 25-42 from 14 U.S. states. Participants were asked about lifestyle, reproductive and environmental exposures, as well as medical information, on biennial questionnaires. Incident SLE cases were self-reported and validated by medical record review (Updated 1997 American College of Rheumatology classification criteria). Those with banked blood samples for genotyping (∼25% of each cohort), were selected and matched by age (± 4 years) and race/ethnicity to women who had donated a blood sample but did not develop SLE. Lifestyle and reproductive variables, including smoking, alcohol use, body mass index, sleep, socioeconomic status, U.S. region, menarche age, oral contraceptive use, menopausal status/postmenopausal hormone use, and family history of SLE or rheumatoid arthritis (RA) were assessed through the questionnaire prior to SLE diagnosis questionnaire cycle (or matched index date). Genome-wide genotyping results were used to calculate a SLE weighted genetic risk score (wGRS) using 86 published single nucleotide polymorphisms (SNPs) and 10 classical HLA alleles associated with SLE. We compared four sequential multivariable logistic regression models of SLE risk prediction, each calculating the area under the receiver operating characteristic curve (AUC): 1) SLE wGRS, 2) SLE/RA family history, 3) lifestyle, environmental and reproductive factors and 4) combining model 1-3 factors. Models were internally validated using a bootstrapped estimate of optimism of the AUC. We also examined similar sequential models to predict anti-dsDNA positive SLE risk.

RESULTS

We identified and matched 138 women who developed incident SLE to 1136 women who did not. Models 1-4 yielded AUCs 0.63 (95%CI 0.58-0.68), 0.64 (95%CI 0.59-0.68), 0.71(95% CI 0.66-0.75), and 0.76 (95% CI 0.72-0.81). Model 4 based on genetics, family history and eight lifestyle and environmental factors had best discrimination, with an optimism-corrected AUC 0.75. AUCs for similar models predicting anti-dsDNA positive SLE risk, were 0.60, 0.63, 0.81 and 0.82, with optimism corrected AUC of 0.79 for model 4.

CONCLUSION

A final model including SLE weighted genetic risk score, family history and eight lifestyle and environmental SLE risk factors accurately classified future SLE risk with optimism corrected AUC of 0.75. To our knowledge, this is the first SLE prediction model based on known risk factors. It might be feasibly employed in at-risk populations as genetic data are increasingly available and the risk factors easily assessed. The NHS cohorts include few non-White women and mean age at incident SLE was early 50s, calling for further research in younger and more diverse cohorts.

Increasing Prevalence of Antinuclear Antibodies in the United States

OBJECTIVE

Growing evidence suggests increasing frequencies of autoimmunity and autoimmune diseases, but findings are limited by the lack of systematic data and evolving approaches and definitions. This study was undertaken to investigate whether the prevalence of antinuclear antibodies (ANA), the most common biomarker of autoimmunity, changed over a recent 25-year span in the US.

METHODS

Serum ANA were measured by standard indirect immunofluorescence assays on HEp-2 cells in 13,519 participants age ≥12 years from the National Health and Nutrition Examination Survey, with approximately one-third from each of 3 time periods: 1988-1991, 1999-2004, and 2011-2012. We used logistic regression adjusted for sex, age, race/ethnicity, and survey design variables to estimate changes in ANA prevalence across the time periods.

RESULTS

The prevalence of ANA was 11.0% (95% confidence interval [95% CI] 9.7-12.6%) in 1988-1991, 11.4% (95% CI 10.2-12.8%) in 1999-2004, and 16.1% (95% CI 14.4-18.0%) in 2011-2012 (P for trend <0.0001), corresponding to ~22.3 million, ~26.6 million, and ~41.5 million affected individuals, respectively. Among adolescents age 12-19 years, ANA prevalence increased substantially, with odds ratios of 2.07 (95% CI 1.18-3.64) and 2.77 (95% CI 1.56-4.91) in the second and third time periods relative to the first (P for trend = 0.0004). ANA prevalence increased in both sexes (especially in men), older adults (age ≥50 years), and non-Hispanic white individuals. These increases in ANA prevalence were not explained by concurrent trends in weight (obesity/overweight), smoking exposure, or alcohol consumption.

CONCLUSION

The prevalence of ANA in the US has increased considerably in recent years. Additional studies to determine factors underlying these increases in ANA prevalence could elucidate causes of autoimmunity and enable the development of preventative measures.

Effects of high fat diet-induced obesity on pathophysiology, immune cells, and therapeutic efficacy in systemic lupus erythematosus

Prior studies have suggested a strong link between obesity and autoimmune diseases. This study aimed to evaluate the effects of high fat diet (HFD)-induced obesity on the disease pathogenesis, immune cell infiltration, and therapeutic efficacy in systemic lupus erythematosus (SLE). Treatment with methylprednisolone significantly increased the survival in the control diet group, but not in the HFD group. An HFD significantly increased the incidence of severe proteinuria and glucose intolerance. Regardless of the diet, treatment with methylprednisolone significantly decreased the serum levels of anti-dsDNA antibodies, IL-2, IL-10, and interferon γ-induced protein 10 (IP-10), and improved the renal pathology scores. Treatment with methylprednisolone significantly lowered the serum levels of IL-6, MCP-1, and TNF-α in the control diet group, but not in the HFD group. HFD significantly increased the proportions of CD45⁺ and M1 cells and significantly decreased the proportion of M2 cells in white adipose tissue; methylprednisolone treatment significantly rescued this effect. In the HFD group, methylprednisolone treatment significantly decreased the M1:M2 and increased the Foxp3⁺:RORγt⁺ cell in the spleen compared with the untreated group. These data improve our understanding of the effect of HFD on the therapeutic efficacy of corticosteroids in SLE treatment, which could have clinical implications.

Obesity Exacerbates Lupus Activity in Fc Gamma Receptor IIb Deficient Lupus Mice Partly through Saturated Fatty Acid-Induced Gut Barrier Defect and Systemic Inflammation

The prevalence of obesity is increasing, and the coexistence of obesity and systemic lupus erythematosus (lupus) is possible. A high-fat diet (HFD) was orally administered for 6 months in female 8-week-old Fc gamma receptor IIb deficient (FcgRIIb-/-) lupus or age and gender-matched wild-type (WT) mice. Lupus nephritis (anti-dsDNA, proteinuria, and increased creatinine), gut barrier defect (fluorescein isothiocyanate dextran), serum lipopolysaccharide (LPS), serum interleukin (IL)-6, liver injury (alanine transaminase), organ fibrosis (liver and kidney pathology), spleen apoptosis (activated caspase 3), and aorta thickness (but not weight gain and lipid profiles) were more prominent in HFD-administered FcgRIIb-/- mice than the obese WT, without injury in regular diet-administered mice (both FcgRIIb-/- and WT). In parallel, combined palmitic acid (PA; a saturated fatty acid) with LPS (PA + LPS) induced higher tumor necrotic factor-α, IL-6, and IL-10 in the supernatant, inflammatory genes (inducible nitric oxide synthase and IL-1β), reactive oxygen species (dihydroethidium), and glycolysis with reduced mitochondrial activity (extracellular flux analysis) when compared with the activation by each molecule alone in both FcgRIIb-/- and WT macrophages. However, the alterations of these parameters were more prominent in PA + LPS-administered FcgRIIb-/- than in the WT cells. In conclusion, obesity accelerated inflammation in FcgRIIb-/- mice, partly due to the more potent responses from the loss of inhibitory FcgRIIb against PA + LPS with obesity-induced gut barrier defect.

Separating the effects of childhood and adult body size on inflammatory arthritis: a Mendelian randomisation study

OBJECTIVES

Using Mendelian randomisation (MR), we examined whether childhood body size affects risk of rheumatoid arthritis (RA), ankylosing spondylitis (AS), psoriatic arthritis (PsA), gout and systemic lupus erythematosus (SLE) after accounting for the effect of adult body size.

METHODS

Genetic instruments for childhood (age 10 years) and adult body size were derived using data from 453 169 individuals from the UK Biobank study (313 and 580 variants respectively), which have been previously validated using body mass index data from three independent populations. Genome-wide association data comprised 22 350 RA, 9069 AS, 3609 PsA, 13 179 gout and 5201 SLE cases. For each outcome, we conducted univariable MR to estimate the total effects of childhood and adult body size, and multivariable MR to examine the independent effect of childhood body size after accounting for adult body size.

RESULTS

Genetically predicted childhood body size had a total effect on risk of PsA (OR 2.18 per change in body size category; 95% CI 1.43 to 3.31), gout (OR 2.18; 95% CI 1.43 to 3.31) and SLE (OR 2.44; 95% CI 1.14 to 5.22), but not RA (OR 0.95; 95% CI 0.70 to 1.29) or AS (OR 0.96; 95% CI 0.61 to 1.52). After accounting for adult body size, the direct effect of childhood body size was little changed for PsA (OR 1.92; 1.14 to 3.25) and SLE (OR 2.69; 1.24 to 5.87) but was attenuated for gout (OR 1.40; 95% CI 0.94 to 2.09).

CONCLUSIONS

Our findings suggest that, for PsA and SLE, the risk conferred from having a larger body size during childhood may not be fully reversable even when a healthy size is achieved in adulthood.

The Intersection of Cellular and Systemic Metabolism: Metabolic Syndrome in Systemic Lupus Erythematosus

A high prevalence of metabolic syndrome (MetS) has been reported in multiple cohorts of systemic lupus erythematosus (SLE) patients, most likely as one of the consequences of autoimmune pathogenesis. Although MetS has been associated with inflammation, its consequences on the lupus immune system and on disease manifestations are largely unknown. The metabolism of immune cells is altered and overactivated in mouse models as well as in patients with SLE, and several metabolic inhibitors have shown therapeutic benefits. Here we review recent studies reporting these findings, as well as the effect of dietary interventions in clinical and preclinical studies of SLE. We also explore potential causal links between systemic and immunometabolism in the context of lupus, and the knowledge gap that needs to be addressed.

Environmental factors associated with juvenile idiopathic inflammatory myopathy clinical and serologic phenotypes

BACKGROUND

Environmental exposures have been associated with the juvenile idiopathic inflammatory myopathies (JIIM). We undertook a questionnaire-based study to evaluate patient-reported exposures as possible risk factors for JIIM.

FINDINGS

One-hundred-seven patients with JIIM were enrolled in a myositis natural history protocol and completed environmental questionnaires. Frequencies of exposures in clinical and myositis-specific autoantibody (MSA) groups were examined. Patients with juvenile dermatomyositis (JDM) and juvenile connective tissue myositis (JCTM) more frequently received an immunization within 1 year of diagnosis compared to juvenile polymyositis (57.5 and 71.4% vs 0.0%, p ≤ 0.017). JCTM patients were more often underweight at diagnosis relative to JDM patients (42.9% vs 7.0%, p = 0.002). MSA-negative patients more frequently had gastroenteritis within a year of diagnosis compared to patients with anti-MDA5 autoantibodies (28.6% vs 0.0%, p = 0.032). Heavy exercise was more frequent in MSA-negative and anti-MDA5 groups compared to the anti-TIF-1 autoantibody group (42.9 and 35.3% vs. 9.0%, p ≤ 0.047). Medications received within 1 year of diagnosis were more frequent in MSA-negative patients relative to those with anti-MDA5 autoantibodies (92.9% vs. 52.8% p = 0.045). Being breastfed > 6 months was more frequent in MSA-negative patients (88.9%) compared to anti-TIF-1 and anti-MDA5 autoantibody groups (41.2 and 28.6%, p ≤ 0.036).

CONCLUSIONS

Certain environmental exposures prior to diagnosis differed among clinical and serologic subgroups of JIIM, suggesting additional exposures to be explored as possible risk factors for JIIM phenotypes.

Endothelial function and endothelial progenitor cells in systemic lupus erythematosus

The observations that traditional cardiovascular disease (CVD) risk factors fail to fully account for the excessive cardiovascular mortality in patients with systemic lupus erythematosus (SLE) compared with the general population have prompted in-depth investigations of non-traditional, SLE-related risk factors that contribute to cardiovascular complications in patients with SLE. Of the various perturbations of vascular physiology, endothelial dysfunction, which is believed to occur in the earliest step of atherosclerosis, has been extensively investigated for its contribution to CVD risk in SLE. Endothelial progenitor cells (EPCs), which play a crucial part in vascular repair, neovascularization and maintenance of endothelial function, are quantitatively and functionally reduced in patients with SLE. Yet, the lack of a unified definition of EPCs, standardization of the quantity and functional assessment of EPCs as well as endothelial function measurement pose challenges to the translation of endothelial function measurements and EPC levels into prognostic markers for CVD in patients with SLE. This Review discusses factors that contribute to CVD in SLE, with particular focus on how endothelial function and EPCs are evaluated currently, and how EPCs are quantitatively and functionally altered in patients with SLE. Potential strategies for the use of endothelial function measurements and EPC quantification as prognostic markers of CVD in patients with SLE, and the limitations of their prognostication potential, are also discussed.

Sex-Specific Environmental Impacts on Initiation and Progression of Multiple Sclerosis

The immunological mechanisms that contribute to multiple sclerosis (MS) differ between males and females. Females are 2–3 times more likely to develop MS compared to males, however the reason for this discrepancy is unknown. Once MS is established, there is a more inflammatory yet milder form of disease in females whereas males generally suffer from more severe disease and faster progression, neural degradation, and disability. Some of these differences relate to genetics, including genetic control of immune regulatory genes on the X-chromosome, as well as immune modulatory properties of sex hormones. Differences in MS development may also relate to how sex interacts with environmental risk factors. There are several environmental risk factors for MS including late-onset Epstein Barr virus infection, low serum vitamin D levels, low UV radiation exposure, smoking, obesity, and lack of physical activity. Most of these risk factors impact males and females differently, either due to biological or immunological processes or through behavioral differences. In this review, we explore these differences further and focus on how the interaction of environmental risk factors with sex hormones may contribute to significantly different prevalence and pathology of MS in males and females.

Association of a Combination of Healthy Lifestyle Behaviors With Reduced Risk of Incident Systemic Lupus Erythematosus

OBJECTIVE

While previous studies have demonstrated an association between individual factors related to lifestyle and the risk of systemic lupus erythematosus (SLE), it is unclear how the combination of these factors might affect the risk of incident SLE. This study was undertaken to prospectively evaluate whether a combination of healthy lifestyle factors is associated with a lower risk of incident SLE and its subtypes (anti-double-stranded DNA [anti-dsDNA]-positive and anti-dsDNA-negative SLE).

METHODS

The study included 185,962 women from the Nurses' Health Study (NHS) and NHSII cohorts, among whom there were 203 incident cases of SLE (96 with anti-dsDNA-positive SLE, 107 with anti-dsDNA-negative SLE) during 4,649,477 person-years of follow-up. The Healthy Lifestyle Index Score (HLIS) was calculated at baseline and approximately every 2 years during follow-up, with scores assigned for 5 healthy lifestyle factors: alcohol consumption, body mass index, smoking, diet, and exercise. A time-varying Cox proportional hazards regression model was used to estimate the adjusted hazard ratios (HRs) with 95% confidence intervals (95% CIs) for the risk of SLE. In addition, the percentage of partial population attributable risk (PAR%) of SLE development was calculated.

RESULTS

A higher HLIS was associated with a lower risk of SLE overall (HR 0.81 [95% CI 0.71-0.94]) and a lower risk of anti-dsDNA-positive SLE (HR 0.78 [95% CI 0.63-0.95]). Women with ≥4 healthy lifestyle factors had the lowest risk of SLE overall (HR 0.42, 95% CI 0.25-0.70) and lowest risk of anti-dsDNA-positive SLE (HR 0.35, 95% CI 0.17-0.75) as compared to women with only 1 healthy behavior or no healthy behaviors. The PAR% of SLE development was 47.7% (95% CI 23.1-66.6%), assuming that the entire population had adhered to at least 4 healthy lifestyle behaviors.

CONCLUSION

These results indicate that the risk of developing SLE, a disease in which significant evidence of genetic involvement has been established, might be reduced by nearly 50% with adherence to modifiable healthy lifestyle behaviors.

Explore comorbidities associated with systemic lupus erythematosus: a total population-based case-control study

BACKGROUND

Because of the increasing incidence and overall burden of systemic lupus erythematosus (SLE), efforts have been made to identify the factors that contribute to SLE onset and progression.

AIM

We conducted a total population-based case-control study to explore the prior comorbidities associated with SLE.

DESIGN AND METHODS

Data were collected from Taiwan's National Health Insurance Research Database. Newly diagnosed SLE patients from 1 January 2010, to 31 December 2013 (n = 2847), were exactly matched at a 1:4 ratio for gender, age, residence and insurance premium to form a non-SLE group. Multivariate conditional logistic regression with stepwise selection was used to find the prior-associated comorbidities.

RESULTS

A total of 38 prior comorbidities were associated with SLE incidence (32 positive and 6 negative associations). Positively associated comorbidities could be categorized as autoimmune-related inflammation of multiple organs including skin, blood, liver, tooth, thyroid, musculoskeletal and connective tissue. Among them, diffuse diseases of connective tissue (International Classification of Disease, Ninth Revision, Clinical Modification 710) exhibited the most robust association (OR = 5.68, 95% CI = 4.02-8.03, P < 0.001) in the 5 years before the index date. Negatively associated comorbidities could be attributed to diabetes mellitus and pregnancy related symptoms.

CONCLUSIONS

Our results supported that increased awareness of SLE may be warranted for patients with autoimmune-related comorbidities of multiple organs. However, diabetes mellitus and pregnancy related symptoms were negatively associated with SLE incidence in this study. Further studies are warranted to elucidate the possible underlying mechanism and for better understanding the pathogenesis of SLE.

Autoimmune Connective Tissue Diseases: Systemic Lupus Erythematosus and Rheumatoid Arthritis

Systemic lupus erythematosus and rheumatoid arthritis are just 2 of several autoimmune connective tissue diseases that are primarily chronic in nature but can present to the emergency department by virtue of an acute exacerbation of disease. Beyond an acute exacerbation of disease, their predilection for invading multiple organ systems lends itself to the potential for patients presenting to the emergency department with either a single or isolated symptom or a myriad of signs and/or symptoms indicative of a degree of disease complexity and severity that warrant timely recognition and resuscitation.

Association of Child Abuse and Systemic Lupus Erythematosus in Black Women During Adulthood

OBJECTIVE

Exposure to psychosocial stressors may contribute to the onset of systemic lupus erythematosus (SLE) through dysregulation of the adaptive stress response. The present study was undertaken to assess the relationship of childhood physical and sexual abuse to risk of SLE among Black women.

METHODS

Using data from the Black Women's Health Study, we followed 36,152 women from 1995 through 2015 with biennial questionnaires. Women reported on exposure to abuse during childhood (up to age 11) in 2005. Self-reported cases of incident SLE were confirmed as meeting the American College of Rheumatology SLE classification criteria by medical record review. Cox proportional hazards regression models were used to estimate hazard ratios (HRs) and 95% confidence intervals (95% CIs) for SLE among women exposed to physical or sexual abuse during childhood, controlling for potential confounders.

RESULTS

We confirmed 101 cases of incident SLE and identified patients who had completed questions on child abuse during 670,822 person-years of follow-up. Both physical and sexual abuse during childhood were associated with statistically significant increases in SLE incidence. The HR for SLE associated with ≥2 episodes of severe sexual abuse compared to no abuse was 2.51 (95% CI 1.29-4.85) after adjustment for alcohol consumption, smoking, body mass index, oral contraceptive use, age at menarche, and parental education. The multivariable-adjusted HR for SLE with ≥5 episodes of severe physical abuse was 2.37 (95% CI 1.13-4.99).

CONCLUSION

Our results suggest that sexual and physical abuse during childhood increase SLE risk during adulthood among Black women. Research is necessary both to confirm this finding and to understand potential mediating mechanisms.

Low Dietary Fiber Intake Links Development of Obesity and Lupus Pathogenesis

Changed dietary habits in Western countries such as reduced fiber intake represent an important lifestyle factor contributing to the increase in inflammatory immune-mediated diseases. The mode of action of beneficial fiber effects is not fully elucidated, but short-chain fatty acids (SCFA) and gut microbiota have been implicated. The aim of this study was to explore the impact of dietary fiber on lupus pathology and to understand underlying mechanisms. Here, we show that in lupus-prone NZB/WF1 mice low fiber intake deteriorates disease progression reflected in accelerated mortality, autoantibody production and immune dysregulation. In contrast to our original assumption, microbiota suppression by antibiotics or direct SCFA feeding did not influence the course of lupus-like disease. Mechanistically, our data rather indicate that in low fiber-fed mice, an increase in white adipose tissue mass, fat-inflammation and a disrupted intestinal homeostasis go along with systemic, low-grade inflammation driving autoimmunity. The links between obesity, intestinal leakage and low-grade inflammation were confirmed in human samples, while adaptive immune activation predominantly correlated with lupus activity. We further propose that an accelerated gastro-intestinal passage along with energy dilution underlies fiber-mediated weight regulation. Thus, our data highlight the often-overlooked effects of dietary fiber on energy homeostasis and obesity prevention. Further, they provide insight into how intricately the pathologies of inflammatory immune-mediated conditions, such as obesity and autoimmunity, might be interlinked, possibly sharing common pathways.

[The effect of obesity on disease activity of inflammatory rheumatic diseases]

One of the most recent scientific fields is the interaction between the immune system and metabolic processes. These interactions increasingly involve intracellular and extracellular signaling molecules and their receptors as well as molecular mechanisms that are used by both systems. The result of these intensive interactions is characterized by the term "metaflammation" and involves in particular, the ubiquitous adipose tissue present throughout the body. The links identified to date between the immune system and metabolism play a greater role in inflammatory rheumatic joint diseases than previously thought. In general, a markedly high body mass index (BMI) in particular, is associated with increased inflammatory activity and this is independent of the underlying disease entity. A higher BMI at the beginning of an immunomodulatory therapy also causes a more difficult response to the medication. Thus, the current scientific objective is to identify the individual "immuno-metabolic" pathways in order to apply the medications specifically to the site of action. Furthermore, all newer therapeutic agents, especially those specifically acting against individual immunological molecules, should be systematically analyzed with respect to their metabolic concomitant effects and their influence on metabolic comorbidities.

Genetic and molecular biology of systemic lupus erythematosus among Iranian patients: an overview

BACKGROUND

Systemic lupus erythematosus (SLE) is a clinicopathologically heterogeneous chronic autoimmune disorder affecting different organs and tissues. It has been reported that there is an increasing rate of SLE incidence among Iranian population. Moreover, the Iranian SLE patients have more severe clinical manifestations compared with other countries. Therefore, it is required to introduce novel methods for the early detection of SLE in this population. Various environmental and genetic factors are involved in SLE progression.

MAIN BODY

In present review we have summarized all of the reported genes which have been associated with clinicopathological features of SLE among Iranian patients.

CONCLUSIONS

Apart from the reported cytokines and chemokines, it was interestingly observed that the apoptosis related genes and non-coding RNAs were the most reported genetic abnormalities associated with SLE progression among Iranians. This review clarifies the genetics and molecular biology of SLE progression among Iranian cases. Moreover, this review paves the way of introducing an efficient panel of genetic markers for the early detection and better management of SLE in this population.

Characterization of the inflammatory-metabolic phenotype of heart failure with a preserved ejection fraction: a hypothesis to explain influence of sex on the evolution and potential treatment of the disease

Accumulating evidence points to the existence of an inflammatory-metabolic phenotype of heart failure with a preserved ejection fraction (HFpEF), which is characterized by biomarkers of inflammation, an expanded epicardial adipose tissue mass, microvascular endothelial dysfunction, normal-to-mildly increased left ventricular volumes and systolic blood pressures, and possibly, altered activity of adipocyte-associated inflammatory mediators. A broad range of adipogenic metabolic and systemic inflammatory disorders - e.g. obesity, diabetes and metabolic syndrome as well as rheumatoid arthritis and psoriasis - can cause this phenotype, independent of the presence of large vessel coronary artery disease. Interestingly, when compared with men, women are both at greater risk of and may suffer greater cardiac consequences from these systemic inflammatory and metabolic disorders. Women show disproportionate increases in left ventricular filling pressures following increases in central blood volume and have greater arterial stiffness than men. Additionally, they are particularly predisposed to epicardial and intramyocardial fat expansion and imbalances in adipocyte-associated proinflammatory mediators. The hormonal interrelationships seen in inflammatory-metabolic phenotype may explain why mineralocorticoid receptor antagonists and neprilysin inhibitors may be more effective in women than in men with HFpEF. Recognition of the inflammatory-metabolic phenotype may improve an understanding of the pathogenesis of HFpEF and enhance the ability to design clinical trials of interventions in this heterogeneous syndrome.

Prevalence and Associated Factors of Lupus in the United States: Third National Health and Nutritional Examination Survey (NHANES III)

This study aimed to examine the prevalence and associated factors of lupus among adults in the United States. This study included 20,045 participants aged 17 years and older from the Third National Health and Nutritional Examination Survey (NHANES III) from 1988 to 1994. Their lupus status was determined by survey questions in terms of a clinician's diagnosis. Demographics and laboratory test results of all participants were collected, including biochemistry, nutrition, and antibody biomarkers. Continuous variables were compared between cases with reported lupus and non-case controls by t-test, while the Chi-square test was used for categorical variables. Weighted multivariate-adjusted logistic regression models after adjustment of covariates were used to identify associated factors of lupus risk. Of 20,045 participants, 40 people who self-reported a lupus diagnosis were identified, giving a prevalence of 241 per 100,000 (n = 40; 95% confidence interval: 133–349 per 100,000). Many factors differed significantly between lupus cases and controls. Multivariate logistic regression analysis further identified previous and current smoking along with elevated serum levels of chloride, globulin, lactate dehydrogenase, uric acid, cholesterol, and lutein or zeaxanthin as risk factors; while protective factors against lupus included non-white race, obesity, elevated serum levels of bicarbonate, creatinine, total calcium, and vitamin B12, as well as elevated urinary albumin and iodine. Our nationwide data indicate that race, obesity, cigarette smoking, and certain biomarkers such as serum lutein or zeaxanthin, calcium, and cholesterol may be associated with the development or progression of lupus, although these findings need to be confirmed in further prospective investigations.

Increasing Prevalence of Antinuclear Antibodies in the United States

OBJECTIVE

Growing evidence suggests increasing frequencies of autoimmunity and certain autoimmune diseases, but findings are limited by the lack of systematic data and evolving approaches and definitions. This study was undertaken to investigate whether the prevalence of antinuclear antibodies (ANA), the most common biomarker of autoimmunity, changed over a recent 25-year span in the US.

METHODS

Serum ANA were measured by standard indirect immunofluorescence assays on HEp-2 cells in 14,211 participants age ≥12 years from the National Health and Nutrition Examination Survey, with approximately one-third from each of 3 time periods: 1988-1991, 1999-2004, and 2011-2012. We used logistic regression adjusted for sex, age, race/ethnicity, and survey design variables to estimate changes in ANA prevalence across the time periods.

RESULTS

The prevalence of ANA was 11.0% (95% confidence interval [95% CI] 9.7-12.6%) in 1988-1991, 11.5% (95% CI 10.3-12.8%) in 1999-2004, and 15.9% (95% CI 14.3-17.6%) in 2011-2012 (P for trend < 0.0001), which corresponds to ~22 million, ~27 million, and ~41 million affected individuals, respectively. Among adolescents age 12-19 years, ANA prevalence increased substantially, with odds ratios (ORs) of 2.02 (95% CI 1.16-3.53) and 2.88 (95% CI 1.64-5.04) in the second and third time periods relative to the first (P for trend < 0.0001). ANA prevalence increased in both sexes (especially in men), older adults (age ≥50 years), and non-Hispanic whites. These increases in ANA prevalence were not explained by concurrent trends in weight (obesity/overweight), smoking exposure, or alcohol consumption.

CONCLUSION

The prevalence of ANA in the US has increased considerably in recent years. Additional studies to determine factors underlying these increases in ANA prevalence could elucidate causes of autoimmunity and enable the development of preventative measures.

Metabolic determinants of lupus pathogenesis

The metabolism of healthy murine and more recently human immune cells has been investigated with an increasing amount of details. These studies have revealed the challenges presented by immune cells to respond rapidly to a wide variety of triggers by adjusting the amount, type, and utilization of the nutrients they import. A concept has emerged that cellular metabolic programs regulate the size of the immune response and the plasticity of its effector functions. This has generated a lot of enthusiasm with the prediction that cellular metabolism could be manipulated to either enhance or limit an immune response. In support of this hypothesis, studies in animal models as well as human subjects have shown that the dysregulation of the immune system in autoimmune diseases is associated with a skewing of the immunometabolic programs. These studies have been mostly conducted on autoimmune CD4⁺ T cells, with the metabolism of other immune cells in autoimmune settings still being understudied. Here we discuss systemic metabolism as well as cellular immunometabolism as novel tools to decipher fundamental mechanisms of autoimmunity. We review the contribution of each major metabolic pathway to autoimmune diseases, with a focus on systemic lupus erythematosus (SLE), with the relevant translational opportunities, existing or predicted from results obtained with healthy immune cells. Finally, we review how targeting metabolic programs may present novel therapeutic venues.

Early life body size, growth and risks of systemic lupus erythematosus - A large Danish observational cohort study

OBJECTIVES

Adult obesity may increase the risks of systemic lupus erythematosus (SLE), and there are genetic links between adult height and SLE. Thus, it is plausible that size earlier in life may be important in the aetiology of SLE as well. We investigated whether birthweight, childhood body mass index (BMI; [kg/m²]), height and growth are associated with risks of adult SLE.

METHODS

The study included 346,627 children from the Copenhagen School Health Records Register, born 1930-1996 with measured weights and heights from 7-13 years. Birthweight information was available from 1936. Linkages were made to the Danish National Patient Register for information on registrations of SLE. During follow-up, 435 individuals (366 women) were registered with SLE. Cox proportional hazards regressions were performed to estimate hazard ratios (HR) and 95% confidence intervals (CI).

RESULTS

No differences by sex were detected in any of the associations. Birthweight was not associated with SLE risks. Childhood BMI and height were positively and linearly associated with SLE risks. For BMI at age 7, the HR was 1.11 (95% CI: 1.01-1.23) per z-score. For height at age 7, the HR was 1.13 (95% CI: 1.02-1.24) per z-score. The estimates were similar in magnitude across all childhood ages for BMI and height. There were limited indications that change in BMI or growth in height during childhood influence the risks of SLE in adulthood.

CONCLUSIONS

Childhood body size is associated with risks of adult SLE, which supports the hypothesis that early life factors are important in SLE aetiology.

Interplay between the Adaptive Immune System and Insulin Resistance in Weight Loss Induced by Bariatric Surgery

Low-grade chronic inflammation plays a pivotal role among other pathophysiological mechanisms involved in obesity. Innate and adaptive immune cells undergo systemic proinflammatory polarization that gives rise to an increased secretion of proinflammatory cytokines, which in turn leads to insulin resistance. Bariatric surgery is currently the most effective treatment for obesity, as it brings on significant weight loss, glucose metabolism improvement, and a decrease in systemic inflammation biomarkers. After bariatric surgery, several changes have been reported to occur in adaptive immunity, including reduction in CD4+ and CD8+ T cell counts, a decrease in the Th1/Th2 ratio, an increase in B regulatory cells, and reduction in proinflammatory cytokine secretion. Overall, there seems to be a major shift in several lymphocyte populations from a proinflammatory to an anti-inflammatory phenotype. Furthermore, increased antioxidant activity and reduced lipid and DNA oxidation products have been reported after bariatric surgery in circulating mononuclear cells. This paper highlights the shift in the adaptive immune system in response to weight loss and improved insulin sensitivity, as well as the interplay between immunological and metabolic adaptations as a result of bariatric surgery. Finally, based on data from research, we propose several mechanisms such as changes in adaptive immune cell phenotypes and their by-products, recruitment in adipose tissue, reduced oxidative stress, and modification in metabolic substrate availability as drivers to reduce low-grade chronic inflammation after bariatric surgery in severe obesity.

Relationship of Excess Weight with Clinical Activity and Dietary Intake Deficiencies in Systemic Lupus Erythematosus Patients

Obesity and nutrients intake deficiencies may contribute to the clinical manifestations and inflammatory processes in systemic lupus erythematosus (SLE). The aim of this study was to assess the relationship between nutritional status and dietary intake with clinical variables in Mexican-mestizo SLE patients. A cross-sectional study was conducted in 130 female SLE patients, classified by the 1997 SLE American College of Rheumatology (ACR) criteria; the clinical activity was evaluated by the Mexican-Systemic Lupus Erythematosus-Disease Activity Index (Mex-SLEDAI); body mass index (BMI) by the World Health Organization (WHO) criteria; the energy calculation and nutritional intake were performed by Nutritionist Pro Diet software. SLE patients with excess weight (BMI > 25 kg/m²) showed a higher score of clinical activity (Mex-SLEDAI = 2; p = 0.003), higher clinical activity prevalence (40.9%; p = 0.039) and a significant association for high clinical activity (odds ratio (OR) = 2.52; 95% confidence interval (CI) = 1.08-5.9; p = 0.033), in comparison with patients without excess weight (BMI < 25 kg/m²). In particular, the excess weight increased the Mex-SLEDAI score (β coefficient = 1.82; R² = 0.05; p = 0.005). Also, the SLE patients presented a high prevalence (%) of deficient consumption (cut-off point: <67% of dietary adequacy) of vitamin E (100%), iodine (96%), omega 3 (93.44%), biotin (78%), vitamin K (73.33%), iron (67%), vitamin D (63.3%), potassium (59%), folic acid (56.67%), pantothenic acid (43.3%), vitamin A (41.67%) and zinc (32%). In conclusion, in SLE patients the excess weight was associated with increased clinical activity and to the presence of deficiencies in some essential nutrients ingested.

Autoantibodies in SLE: prediction and the p value matrix

Autoantibodies (AA) and antinuclear antibodies (ANA) serve as key diagnostic and classification criteria for systemic lupus erythematosus (SLE). More than 200 different AA have been reported in SLE, although only a handful (<20) are considered "mainstream" because they are widely and routinely used in diagnostic, research and clinical medicine. Although the vast majority of AA have been relegated to the diminished status of "orphan" AA, some serve as predictors of SLE because they first appear in very early or subclinical SLE. Some AA are pathogenic, whereas others are thought to protect against or ameliorate disease progression and, hence, taken together can be used as predictive biomarkers of prognosis. Although studies have shown that specific AA are detected in the preclinical phase of SLE and are biomarkers of increased risk of developing the disease, AA are currently not widely used to predict very early SLE in individuals who have low pretest probability of disease. With the advent of multianalyte arrays with analytic algorithms, emerging evidence indicates that when certain combinations of biomarkers, such as the interferon signature and stem cell factor accompany AA and ANA, the predictive power for SLE is markedly increased.

Comparison of the Clinical Implications among Five Different Nutritional Indices in Patients with Lupus Nephritis

Systemic lupus erythematosus (SLE) is characterized with aberrant responses in the immune systems and lupus nephritis (LN) is one of the most serious complications of SLE. This study evaluated the clinical significance of different nutritional indices in 207 renal biopsy-proven LN patients. The clinical and laboratory data were reviewed, and five different nutritional indices were calculated: (i) Controlling nutritional status (CONUT) score; (ii) prognostic nutritional index (PNI); (iii) nutritional risk index; (iv) neutrophil-to-lymphocyte ratio; and (v) body mass index. The factors associated with end-stage renal failure (ESRF) were assessed using a Cox-proportional hazard analysis. The patients with ESRF had significantly lower median PNI (31.1 vs. 34.7, p = 0.012) than those without ESRF at baseline. The CONUT score and PNI had the highest correlation between the SLE disease activity index-2000 (r = 0.467 and p = −0.356, all p < 0.001) and was significantly associated with SLE activity-related measures. In the Cox-proportional hazard analysis, PNI (odds ratio 0.925, 95% confidence interval 0.865–0.989, p = 0.022) was independently associated with ESRF along with creatinine and chronicity index, and the renal survival rate was significantly lower in patients with PNI ≤35.41 than in those with PNI >35.41 (p = 0.003). Among nutritional indices, the CONUT score and PNI better correlated with disease activity and PNI was associated with ESRF.

Metabolic syndrome and systemic lupus erythematosus: the connection

Introduction: The metabolic syndrome (MetS) is now recognized as a chronic proinflammatory and prothrombotic state that aggravates insulin resistance, oxidative injury, and cardiovascular risk. MetS is more prevalent in patients with systemic lupus erythematosus (SLE), a prototype of systemic autoimmune disease associated with premature atherosclerosis that cannot be accounted by traditional vascular risk factors alone. Dysregulation of the cytokines and adipokines is a common feature in both SLE and MetS, suggesting a complex relationship among autoimmunity, obesity, inflammation, and atherosclerosis. Areas covered: This review summarizes the prevalence of MetS and its effect on cardiovascular outcome and organ damage in patients with SLE. The pathophysiology of MetS and its relevance to SLE is also briefly discussed. Expert opinion: Imbalance of adipokine production in MetS contributes to inflammation and atherosclerosis. MetS predisposes SLE patients to new cardiovascular events and vascular mortality, as well as the development of chronic kidney disease and diabetes mellitus. However, conflicting results have been reported in the literature regarding the levels of the proinflammatory leptin and anti-inflammatory adiponectin, and their relationship with disease activity in SLE patients. While lifestyle modifications and targeting dyslipidemia, hypertension and diabetes mellitus is essential, there is little information on the efficacy and safety of metformin and hydroxychloroquine in alleviating insulin resistance in SLE or MetS. Further research on adipokines in SLE and the role of anti-obesity medications and probiotics in MetS is necessary.

Obesity and sarcoidosis: consequence or contributor?

PURPOSE OF REVIEW

Sarcoidosis is a multisystem disease of unknown cause. Obesity can affect many physiological factors. The relationship between obesity and sarcoidosis is unclear, and can been described as posing a 'chicken and egg' scenario for the patient as it is not always clear whether it is a consequence of, or a risk factor for any disease. The purpose of this review is to examine the dual roles of obesity on sarcoidosis morbidity and the incidence.

RECENT FINDINGS

Obesity magnifies the symptoms of sarcoidosis and corticosteroid therapy increases BMI. Prospective epidemiologic studies started to explore the role of obesity as a potential risk factor for sarcoidosis. Three studies in the United States, and one study in Denmark, have demonstrated significantly increased risks of sarcoidosis among obese compared with nonobese patients; risk estimates ranged from 1.42 [95% confidence interval (CI), 1.07-1.89] to 3.59 (95% CI, 2.31-5.57).

SUMMARY

Obesity can be both a consequence of sarcoidosis treatment, and a contributor to disease risk likely through the pro-inflammatory environment of obesity. Prospective epidemiologic cohort studies are needed to explore the cause of sarcoidosis and insight into possible avenues of treatment development and prevention.

Association of Childhood Abuse with Incident Systemic Lupus Erythematosus in Adulthood in a Longitudinal Cohort of Women

OBJECTIVE

Exposure to severe stressors may alter immune function and augment inflammation and cytokine release, increasing risk of autoimmune disease. We examined whether childhood abuse was associated with a heightened risk of incident systemic lupus erythematosus (SLE).

METHODS

Data were drawn from the Nurses' Health Study II, a cohort of US female nurses enrolled in 1989, followed with biennial questionnaires. We measured childhood physical and emotional abuse with the Physical and Emotional Abuse Subscale of the Childhood Trauma Questionnaire and sexual abuse with the Sexual Maltreatment Scale of the Parent-Child Conflict Tactics Scale, both administered in 2001. We identified incident SLE (≥ 4 American College of Rheumatology 1997 classification criteria) through 2015. We used multivariable Cox regression models to evaluate the association between childhood abuse and SLE, accounting for potential confounders (e.g., parental education, occupation, home ownership) and mediators [e.g., depression, posttraumatic stress disorder (PTSD)].

RESULTS

Among 67,516 women, there were 94 cases of incident SLE. In adjusted models, exposure to the highest versus lowest physical and emotional abuse was associated with 2.57 times greater risk of SLE (95% CI 1.30-5.12). We found that 17% (p < 0.0001) of SLE risk associated with abuse could be explained by depression and 23% (p < 0.0001) by PTSD. We did not observe a statistically significant association with sexual abuse (HR 0.84, 95% CI 0.40-1.77, highest vs lowest exposure).

CONCLUSION

We observed significantly increased risk of SLE among women who had experienced childhood physical and emotional abuse compared with women who had not. Exposure to childhood adversity may contribute to development of SLE.

[What's new in internal medicine?]

What's new in internal medicine will be dedicated to three topics: i) inflammatory myopathies constituting a heterogenous group of diseases whose clinical manifestations, immunological abnormalities, treatment response and outcomes vary widely; ii) alterations of gut microbiota contributing to the occurrence or development of a range of conditions, including autoimmune diseases for which further work is necessary to understand the correlation of dysbiosis with these diseases; iii) the reciprocal relationship between obesity, metabolic syndrome, atherosclerosis and autoimmune diseases. New data concerning systemic sclerosis, cutaneous vasculitis, adult Still's disease, autoantibodies anti DFS70, Epstein Barr virus and autoimmune diseases were also highlighted.

A prospective study of obesity and risk of systemic lupus erythematosus (SLE) among Black women

BACKGROUND

Obesity may influence systemic lupus erythematous (SLE) pathogenesis via stimulation of systemic inflammation, but the relationship between obesity and SLE risk is unclear. Past studies have predominantly assessed White women, while Black women have higher prevalence of both obesity and SLE.

METHODS

We prospectively assessed the relationship between Body Mass Index (BMI, kg/m²) and incident SLE within the Black Women's Health Study (median age 38 at entry in 1995). Height and weight at age 18 and during follow-up were self-reported. We confirmed incident SLE cases by updated American College of Rheumatology criteria and collected covariates prospectively. Cox proportional hazards regression models, adjusted for potential confounders, estimated hazard ratios (HRs) and 95% confidence intervals (CIs) for categories of updated BMI and risk of SLE, relative to BMI 20-24.9 ("normal" BMI). Secondary analyses investigated BMI at age 18, BMI in 1995 at cohort entry, cumulative updated BMI and "lagged" BMI (≥4 years prior to outcome window to address possible reverse causation).

RESULTS

Adult obesity was not related to SLE risk: HR for BMI ≥30 ("obesity") relative to normal BMI at ≥4 years prior to SLE diagnosis was 0.90 (95% CI 0.53-1.54). However, obesity at age 18 was associated with increased risk: HR 2.38 (95% CI 1.26-4.51) for ≥30 vs. normal BMI.

CONCLUSIONS

Among these Black women, obesity as a teenager was associated with increased SLE risk in adulthood. Further studies are necessary to understand the biologic mechanisms and windows of exposure for the relationship of obesity to SLE pathogenesis.

Update on the epidemiology, risk factors, and disease outcomes of systemic lupus erythematosus

Obtaining an updated view of the epidemiology, risk factors, and prognosis of systemic lupus erythematosus (SLE) is pivotal to our understanding of the disease burden. Recent community-based studies with comprehensive methodology provided more accurate disease occurrence estimates and suggested that SLE may be more frequent than previously thought. Gender, race, and socioeconomic status are important disease determinants, and there is increasing appreciation of the contribution of family history and environmental exposures in SLE susceptibility. Owing to its systemic nature, assessment of disease activity is challenging, also pertaining to efforts to improve trial endpoints for better discrimination between active drug and placebo. Notably, emerging evidence supports that remission or low disease activity states and prevention of flares are realistic targets in the management of SLE associated with improved prognosis. For the future, we anticipate that high-throughput analyses in patient cohorts will enhance the identification of robust biomarkers for diagnosis, risk stratification, and personalized treatment.

Impact of obesity on autoimmune arthritis and its cardiovascular complications

Obesity can instigate and sustain a systemic low-grade inflammatory environment that can amplify autoimmune disorders and their associated comorbidities. Metabolic changes and inflammatory factors produced by the adipose tissue have been reported to aggravate autoimmunity and predispose the patient to cardiovascular disease (CVD) and metabolic comorbidities. Rheumatoid arthritis (RA) and psoriatic arthritis (PsA) are autoimmune arthritic diseases, often linked with altered body mass index (BMI). Severe joint inflammation and bone destruction have a debilitating impact on the patient's life; there is also a staggering risk of cardiovascular morbidity and mortality. Furthermore, these patients are at risk of developing metabolic symptoms, including insulin resistance resulting in type 2 diabetes mellitus (T2DM). In addition, arthritis severity, progression and response to therapy can be markedly affected by the patient's BMI. Hence, a complex integrative pathogenesis interconnects autoimmunity with metabolic and cardiovascular disorders. This review aims to shed light on the network that connects obesity with RA, PsA, systemic lupus erythematosus and Sjӧgren's syndrome. We have focused on clarifying the mechanism by which obesity affects different cell types, inflammatory factors and traditional therapies in these autoimmune disorders. We conclude that to further optimize arthritis therapy and to prevent CVD, it is imperative to uncover the intricate relation between obesity and arthritis pathology.

Inflammation, obesity and rheumatic disease: common mechanistic links. A narrative review

Obesity represents a rising global health concern, linked to significant social, psychological and physical burden to the individual affected, people around them and the society as a whole. Obesity has been described as a low-grade inflammatory condition, associated with increased production of pro-inflammatory mediators like tumor necrosis factor alpha or interleukin 6 and altered expression of adipokines. Adipokines, mainly produced by adipose tissue, have mixed pro- and anti-inflammatory properties. Obesity rarely exists on its own; instead, it tends to coexist with (often multiple) other comorbidities, including metabolic, cardiovascular, and rheumatic and musculoskeletal diseases (RMDs). In the case of RMDs, evidence is rapidly accumulating on common mechanistic pathways implicated in the inflammatory states seen between RMDs and obesity. Although there remain unanswered questions on the exact mechanisms of inflammation that link obesity to RMDs, what is becoming increasingly known is the association between obesity and adverse clinical outcomes in RMDs. This narrative review discusses insights into mechanisms of inflammation linking obesity and RMDs and evidence on the impact of obesity on treatment response and important disease outcomes. We highlight the importance of targeting obesity, a common and modifiable comorbidity, as part of the routine care of people with RMDs.