Influence of Alcohol Consumption on the Risk of Systemic Lupus Erythematosus Among Women in the Nurses' Health Study Cohorts

Intakes of Unprocessed and Minimally Processed and Ultraprocessed Food Are Associated with Diet Quality in Female and Male Health Professionals in the United States: A Prospective Analysis

BACKGROUND

High unprocessed and minimally processed food (UMP) intake has been associated with high-quality diets, whereas the opposite has been shown for ultraprocessed food (UPF). Nevertheless, the association between UMP and UPF consumption and diet quality over the long-term warrants further examination.

OBJECTIVE

This study aimed to assess whether UMP and UPF intake are associated with three diet-quality metrics in female and male health professionals from two US cohorts over 3 decades of follow-up.

DESIGN

This was a cohort study, including data from the Nurses' Health Study (NHS), from 1986 to 2010 (N = 51,956) and the Health Professionals Follow-up Study (HPFS) from 1986 to 2006 (n = 31,307).

PARTICIPANTS AND SETTING

Participants were invited in 1976 (NHS) and 1986 (HPFS) to respond to mailed questionnaires every 2 to 4 years and diet was assessed with a semi-quantitative food frequency questionnaire every 4 years.

MAIN EXPOSURE MEASURES

UMP and UPF intake were calculated using the NOVA classification.

STATISTICAL ANALYSES

Generalized estimating equations for marginal means and repeated cross-sectional associations between diet-quality metrics and quintiles of UMP and UPF. Diets were assessed every 4 years from 1986 to 2010.

RESULTS

With increasing quintiles of UMP intakes, the Alternate Healthy Eating Index-2010 increased 7.1% (3.80 points, 95% CI 3.66 to 3.93) in the NHS and 10.1% (5.75 points, 95% CI 5.52 to 5.98) in the HPFS; the Mediterranean diet index increased 11.7% (0.50 points, 95% CI 0.47 to 0.52) in the NHS and 14.0% (0.64 points, 95% CI 0.60 to 0.68) in the HPFS; and the Dietary Approaches To Stop Hypertension diet score increased 7.5% (1.81 points, 95% CI 1.76 to 1.87) in the NHS and 10.6% (2.66 points, 95% CI 2.57 to 2.76) in the HPFS. In the fifth quintile of UPF intake compared with the first, the Alternate Healthy Eating Index-2010 was -9.3% (-4.60 points, 95% CI -4.73 to -4.47) lower in the NHS and -13.7% (-6.89 points, 95% CI -7.12 to -6.66) lower in the HPFS; the Mediterranean diet index was -14.7% (-0.55 points, 95% CI -0.57 to -0.53) lower in the NHS, and -19.0% (-0.74 points, 95% CI -0.78 to -0.70) lower in the HPFS; and the Dietary Approaches To Stop Hypertension diet score was -8.1% (-1.81 points, 95% CI -1.86 to -1.76) lower in the NHS and -12.8% (-2.84 points, 95% CI -2.93 to -2.74) lower in the HPFS.

CONCLUSIONS

Consumption of UMP was associated with better dietary quality, whereas consumption of UPF was associated with poorer dietary quality.

Appendicitis is associated with an increased risk of systemic lupus erythematosus: a nationwide, population-based, case-control study

OBJECTIVE

To examine the association between appendicitis and the risk of systemic lupus erythematosus (SLE).

METHODS

Using claims data from the 2003-2013 Taiwanese National Health Insurance Research Database, we selected 6054 patients with newly diagnosed SLE from 2007 to 2012 and 36,324 age-, sex- and year of SLE diagnosis date-matched (1:6) non-SLE controls. After controlling for potential confounders, a multivariable conditional logistic regression model was used to calculate the adjusted odds ratio (aOR) with 95% confidence interval (CI) for the association of appendicitis history with SLE. Sensitivity analyses were conducted using various definitions of appendicitis. Subgroup analyses were conducted to examine possible modification effects by age, gender, level of urbanization, income and Charlson Comorbidity Index (CCI).

RESULTS

The average age of patients was 38 years old in both groups. The proportion of females was 86.5%. 75 (1.2%) of SLE cases and 205 (0.6%) of non-SLE controls had appendicitis history before the index date. After adjusting for potential confounding factors, appendicitis was associated with a higher risk of SLE (aOR, 1.84; 95% CI, 1.34-2.52), and such association remained robust after variation of appendicitis definition. No significant modification effects were found for the association between appendicitis and SLE by age, gender, urbanization level, income and CCI.

CONCLUSION

This nationwide, population-based case-control study demonstrates an association between appendicitis and incident SLE. Lack of individual smoking status is a major limitation. Key Points • Appendicitis was significantly associated with an increased risk of SLE. • Such association remained robust using various definitions of appendicitis.

Association of alcohol consumption and fatigue in SLE: A cross-sectional study from Lupus Registry of Nationwide Institution (LUNA) cohort

OBJECTIVE

Fatigue is one of the most common complaints and is a potentially modifiable issue in systemic lupus erythematosus (SLE). Studies suggest that alcohol consumption has a protective effect against the development of SLE; however, an association between alcohol consumption and fatigue in patients with SLE has not been studied. Here, we assessed whether alcohol consumption was associated with fatigue using lupus patient-reported outcomes (LupusPRO).

METHODS

This cross-sectional study, conducted between 2018 and 2019, included 534 patients (median age, 45 years; 87.3% female) from 10 institutions in Japan. The main exposure was alcohol consumption, which was defined as the frequency of drinking [<1 day/month (none group), ≤1 day/week (moderate group), and ≥2 days/week (frequent group)]. The outcome measure was the Pain Vitality domain score in LupusPRO. Multiple regression analysis was performed as the primary analysis after adjusting for confounding factors, such as age, sex, and damage. Subsequently, the same analysis was performed as a sensitivity analysis after multiple imputations (MIs) for missing data (n = 580).

RESULTS

In total, 326 (61.0%) patients were categorized into the none group, 121 (22.7%) into the moderate group, and 87 (16.3%) into the frequent group. The frequent group was independently associated with less fatigue compared with none group [β = 5.98 (95% CI 0.19-11.76), p = 0.04], and the results did not substantially deviate after MI.

CONCLUSIONS

Frequent drinking was associated with less fatigue, which highlights the need for further longitudinal studies focusing on drinking habits in patients with SLE.

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.

Life factors acting on systemic lupus erythematosus

Systemic lupus erythematosus (SLE) is a highly heterogeneous autoimmune disease that primarily affects women. Currently, in the search for the mechanisms of SLE pathogenesis, the association of lifestyle factors such as diet, cigarette smoking, ultraviolet radiation exposure, alcohol and caffeine-rich beverage consumption with SLE susceptibility has been systematically investigated. The cellular and molecular mechanisms mediating lifestyle effects on SLE occurrence, including interactions between genetic risk loci and environment, epigenetic changes, immune dysfunction, hyper-inflammatory response, and cytotoxicity, have been proposed. In the present review of the reports published in reputable peer-reviewed journals and government websites, we consider the current knowledge about the relationships between lifestyle factors and SLE incidence and outline directions of future research in this area. Formulation of practical measures with regard to the lifestyle in the future will benefit SLE patients and may provide potential therapy strategies.

Preclinical Autoimmune Disease: a Comparison of Rheumatoid Arthritis, Systemic Lupus Erythematosus, Multiple Sclerosis and Type 1 Diabetes

The preclinical phase of autoimmune disorders is characterized by an initial asymptomatic phase of varying length followed by nonspecific signs and symptoms. A variety of autoimmune and inflammatory manifestations can be present and tend to increase in the last months to years before a clinical diagnosis can be made. The phenotype of an autoimmune disease depends on the involved organs, the underlying genetic susceptibility and pathophysiological processes. There are different as well as shared genetic or environmental risk factors and pathophysiological mechanisms between separate diseases. To shed more light on this, in this narrative review we compare the preclinical disease course of four important autoimmune diseases with distinct phenotypes: rheumatoid arthritis (RA), Systemic Lupus Erythematosus (SLE), multiple sclerosis (MS) and type 1 diabetes (T1D). In general, we observed some notable similarities such as a North-South gradient of decreasing prevalence, a female preponderance (except for T1D), major genetic risk factors at the HLA level, partly overlapping cytokine profiles and lifestyle risk factors such as obesity, smoking and stress. The latter risk factors are known to produce a state of chronic systemic low grade inflammation. A central characteristic of all four diseases is an on average lengthy prodromal phase with no or minor symptoms which can last many years, suggesting a gradually evolving interaction between the genetic profile and the environment. Part of the abnormalities may be present in unaffected family members, and autoimmune diseases can also cluster in families. In conclusion, a promising strategy for prevention of autoimmune diseases might be to address adverse life style factors by public health measures at the population level.

Understanding the Concept of Pre-Clinical Autoimmunity: Prediction and Prevention of Systemic Lupus Erythematosus: Identifying Risk Factors and Developing Strategies Against Disease Development

There is growing evidence that preceding the diagnosis or classification of systemic lupus erythematosus (SLE), patients undergo a preclinical phase of disease where markers of inflammation and autoimmunity are already present. Not surprisingly then, even though SLE management has improved over the years, many patients will already have irreversible disease-related organ damage by time they have been diagnosed with SLE. By gaining a greater understanding of the pathogenesis of preclinical SLE, we can potentially identify patients earlier in the disease course who are at-risk of transitioning to full-blown SLE and implement preventative strategies. In this review, we discuss the current state of knowledge of SLE preclinical pathogenesis and propose a screening and preventative strategy that involves the use of promising biomarkers of early disease, modification of lifestyle and environmental risk factors, and initiation of preventative therapies, as examined in other autoimmune diseases such as rheumatoid arthritis and type 1 diabetes.

Association of Ultraviolet B Radiation and Risk of Systemic Lupus Erythematosus Among Women in the Nurses' Health Studies

OBJECTIVE

Ultraviolet (UV) radiation exposure is associated with photosensitivity, rashes, and flares in systemic lupus erythematosus (SLE). However, it is not known whether UV exposure increases risk of developing SLE. We examined UV exposure and SLE risk in a large prospective cohort.

METHODS

The Nurses' Health Study (NHS) enrolled 121,700 US female nurses in 1976; in 1989, 116,429 nurses were enrolled in NHS II. Biennial questionnaires collected lifestyle and medical data. Self-reported incident SLE by American College of Rheumatology classification criteria was confirmed by medical record review. Ambient UV exposure was estimated by linking geocoded residential addresses with a spatiotemporal UV exposure model. Cox models estimated hazard ratios (HRs) and 95% confidence intervals (95% CIs) across tertiles of time-varying cumulative average UV. We examined SLE risk overall and stratified by anti-Ro/La antibodies and by cutaneous manifestations from 1976 through 2014 (NHS)/2015 (NHS II), adjusting for confounders.

RESULTS

With 6,054,665 person-years of exposure, we identified 297 incident SLE cases; the mean ± SD age at diagnosis was 49.8 ± 10.6 years. At diagnosis, 16.8% of women had +anti-Ro/La, and 80% had either +anti-Ro/La or ≥1 cutaneous manifestation. Compared with the lowest UV exposure tertile, risk of overall SLE was increased, but not significantly (HR 1.28 [95%CI 0.96-1.70]). Women in the highest tertile had increased risk of malar rash (HR 1.62 [95% CI 1.04-2.52]).

CONCLUSION

Cumulative UV exposure was not associated with SLE risk. Higher UV exposure, however, was associated with increased risk of malar rash at presentation. UV exposure may trigger SLE onset with malar rash among susceptible women.

The role of environmental exposures and gene-environment interactions in the etiology of systemic lupus erythematous

Systemic lupus erythematosus (SLE) is a complex, chronic autoimmune disease, whose etiology includes both genetic and environmental factors. Individual genetic risk factors likely only account for about one-third of observed heritability among individuals with a family history of SLE. A large portion of the remaining risk may be attributable to environmental exposures and gene-environment interactions. This review focuses on SLE risk associated with environmental factors, ranging from chemical and physical environmental exposures to lifestyle behaviors, with the weight of evidence supporting positive associations between SLE and occupational exposure to crystalline silica, current smoking, and exogenous estrogens (e.g., oral contraceptives and postmenopausal hormones). Other risk factors may include lifestyle behaviors (e.g., dietary intake and sleep) and other exposures (e.g., ultraviolet [UV] radiation, air pollution, solvents, pesticides, vaccines and medications, and infections). Alcohol use may be associated with decreased SLE risk. We also describe the more limited body of knowledge on gene-environment interactions and SLE risk, including IL-10, ESR1, IL-33, ITGAM, and NAT2 and observed interactions with smoking, UV exposure, and alcohol. Understanding genetic and environmental risk factors for SLE, and how they may interact, can help to elucidate SLE pathogenesis and its clinical heterogeneity. Ultimately, this knowledge may facilitate the development of preventive interventions that address modifiable risk factors in susceptible individuals and vulnerable populations.

Oral Contraceptive and Menopausal Hormone Therapy Use and Risk of Pituitary Adenoma: Cohort and Case-Control Analyses

CONTEXT

No prospective epidemiologic studies have examined associations between use of oral contraceptives (OCs) or menopausal hormone therapy (MHT) and risk of pituitary adenoma in women.

OBJECTIVE

Our aim was to determine the association between use of OC and MHT and risk of pituitary adenoma in two separate datasets.

METHODS

We evaluated the association of OC/MHT with risk of pituitary adenoma in the Nurses' Health Study and Nurses' Health Study II by computing multivariable-adjusted hazard ratios (MVHR) of pituitary adenoma by OC/MHT use using Cox proportional hazards models. Simultaneously, we carried out a matched case-control study using an institutional data repository to compute multivariable-adjusted odds ratios (MVOR) of pituitary adenoma by OC/MHT use.

RESULTS

In the cohort analysis, during 6 668 019 person-years, 331 participants reported a diagnosis of pituitary adenoma. Compared to never-users, neither past (MVHR = 1.05; 95% CI, 0.80-1.36) nor current OC use (MVHR = 0.72; 95% CI, 0.40-1.32) was associated with risk. For MHT, compared to never-users, both past (MVHR = 2.00; 95% CI, 1.50-2.68) and current use (MVHR = 1.80; 95% CI, 1.27-2.55) were associated with pituitary adenoma risk, as was longer duration (MVHR = 2.06; 95% CI, 1.42-2.99 comparing more than 5 years of use to never, P trend = .002). Results were similar in lagged analyses, when stratified by body mass index, and among those with recent health care use. In the case-control analysis, we included 5469 cases. Risk of pituitary adenoma was increased with ever use of MHT (MVOR = 1.57; 95% CI, 1.35-1.83) and OC (MVOR = 1.27; 95% CI, 1.14-1.42) compared to never.

CONCLUSION

Compared to never use, current and past MHT use and longer duration of MHT use were positively associated with higher risk of pituitary adenoma in 2 independent data sets. OC use was not associated with risk in the prospective cohort analysis and was associated with only mildly increased risk in the case-control analysis.

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.

Alcohol as friend or foe in autoimmune diseases: a role for gut microbiome?

Alcohol is well known for promoting systemic inflammation and aggravating multiple chronic health conditions. Thus, alcohol may also be expected to serve as a risk factor in autoimmune diseases. However, emerging data from human and animal studies suggest that alcohol may in fact be protective in autoimmune diseases. These studies point toward alcohol's complex dose-dependent relationship in autoimmune diseases as well as potential modulation by duration and type of alcohol consumption, cultural background and sex. In this review, we will explore alcohol's pro- and anti-inflammatory properties in human and animal autoimmune diseases, including autoimmune diabetes, thyroid disease, systemic lupus erythematosus, rheumatoid arthritis, experimental autoimmune encephalomyelitis and multiple sclerosis. We will also discuss potential mechanisms of alcohol's anti-inflammatory effects mediated by the gut microbiome.

Advanced Glycation End-Products (AGEs) and Their Soluble Receptor (sRAGE) in Women Suffering from Systemic Lupus Erythematosus (SLE)

Systemic lupus erythematosus (SLE) is characterized by abnormal action of the immune system and a state of chronic inflammation. The disease can cause life-threatening complications. Neoepitopes arising from interdependent glycation and oxidation processes might be an element of SLE pathology. The groups included in the study were 31 female SLE patients and 26 healthy female volunteers (the control group). Blood serum samples were obtained to evaluate concentrations of advanced glycation end-products (AGEs), carboxymethyllysine (CML), carboxyethyllysine (CEL), pentosidine, and a soluble form of the receptor for advanced glycation end-products (sRAGE). Compared to a healthy control group, the SLE patients exhibited a higher concentration of AGEs and a lower concentration of sRAGE in serum. There were no statistically significant differences in serum CML, CEL, and pentosidine concentrations between the groups. Therefore, SLE patients could be at risk of intensified glycation process and activation of the proinflammatory receptor for advanced glycation end-products (RAGE), which could potentially worsen the disease course; however, it is not clear which compounds contribute to the increased concentration of AGEs in the blood. Additionally, information about the cigarette smoking and alcohol consumption of the study participants was obtained.

Association of macronutrients and dietary patterns with risk of systemic lupus erythematosus in the Black Women's Health Study

BACKGROUND

Systemic lupus erythematosus (SLE) affects African-American (AA) women disproportionately. The few prospective studies assessing dietary intake in relation to risk of SLE have been conducted in predominantly white populations and have been null.

OBJECTIVES

The present study assessed associations of macronutrients and dietary patterns with risk of SLE in AA women.

METHODS

Data from the Black Women's Health Study was collected prospectively via biennial questionnaires starting in 1995. Participants completed a self-administered 68-item FFQ in 1995. Self-reported SLE was verified through medical record review. We used multivariable (MV) Cox regression models to estimate HRs and 95% CIs for macronutrients, carbohydrates, proteins, total fats, PUFAs, ω-3 fatty acids, ω-6 fatty acids, MUFAs, saturated fats, trans fatty acids, Alternative Healthy Eating Index score, vegetable/fruit and meat/fried food dietary patterns, and a reduced rank regression (RRR)-derived dietary pattern in relation to SLE risk.

RESULTS

We confirmed a total of 114 incident cases of SLE among 51,934 women during 1995-2015. MVHRs and 95% CIs for the highest quintile of intake versus the lowest were HR: 1.96, 95% CI: 1.02, 3.67 for carbohydrates; HR: 0.66, 95% CI: 0.37, 1.18 for protein; and HR: 0.54, 95% CI: 0.28, 1.01 for total fats. MUFAs, saturated fatty acids, and trans fatty acids were significantly associated with a lower risk of SLE. An RRR-derived factor, rich in fruits and sugar-sweetened drinks and low in margarines and butter, red and processed meats, fried chicken, poultry, and eggs, which explained 53.4% of the total variation of macronutrients, was the only food pattern associated with increased SLE risk (HR: 1.88, 95% CI: 1.06, 3.35).

CONCLUSION

These analyses suggest that a diet high in carbohydrates and low in fats is associated with increased SLE risk in AA women.

Association of Dietary Quality With Risk of Incident Systemic Lupus Erythematosus in the Nurses' Health Study and Nurses' Health Study II

OBJECTIVE

Knowledge remains scarce regarding diet and systemic lupus erythematosus (SLE) risk. Our objective was to investigate 4 dietary quality scores and SLE risk overall and by anti-double-stranded DNA (anti-dsDNA) positive versus negative subtypes.

METHODS

We studied 79,568 women in the Nurses' Health Study (1984-2014) and 93,554 in the Nurses' Health Study II (1991-2013). Using validated food frequency questionnaires, we calculated 4 dietary scores: the 2010 Alternative Healthy Eating Index (AHEI-2010), the Alternative Mediterranean Diet Score (aMed), the Dietary Approach to Stop Hypertension (DASH), and the Empirical Dietary Inflammatory Pattern (EDIP). Incident SLE was confirmed by medical record review. Time-varying Cox regression models estimated pooled hazard ratios (HRs) and 95% confidence intervals (95% CIs) of SLE risk, overall and by anti-dsDNA, for cumulative average dietary quality score tertiles and individual AHEI-2010 components.

RESULTS

We identified 194 incident SLE cases. SLE risk was similar in women with the highest (versus lowest) dietary scores (AHEI-2010 HR 0.78 [95% CI 0.54-1.14], aMed HR 0.82 [95% CI 0.56-1.18], DASH HR 1.16 [95% CI 0.81-1.66], EDIP HR 0.83 [95% CI 0.57-1.21]). No association was demonstrated for anti-dsDNA+ or anti-dsDNA- SLE risk. Women in the highest (versus lowest) AHEI-2010 tertile of nut/legume intake had a decreased SLE risk (HR 0.59 [95% CI 0.40-0.87]). No association was demonstrated for other AHEI-2010 components and SLE risk.

CONCLUSION

We observed no association between long-term adherence to the AHEI-2010, aMed, DASH, or EDIP scores with SLE risk, suggesting a large effect of dietary quality on SLE risk is unlikely. However, potential reduction in overall SLE risk with high nut/legume intake warrants further investigation.

Alcohol Consumption in Rheumatoid Arthritis: A Path through the Immune System

Benefits and harms of different components of human diet have been known for hundreds of years. Alcohol is one the highest consumed, abused, and addictive substances worldwide. Consequences of alcohol abuse are increased risks for diseases of the cardiovascular system, liver, and nervous system, as well as reduced immune system function. Paradoxically, alcohol has also been a consistent protective factor against the development of autoimmune diseases such as type 1 diabetes, multiple sclerosis, systemic lupus erythematosus, and rheumatoid arthritis (RA). Here, we focused on summarizing current findings on the effects of alcohol, as well as of its metabolites, acetaldehyde and acetate, on the immune system and RA. Heavy or moderate alcohol consumption can affect intestinal barrier integrity, as well as the microbiome, possibly contributing to RA. Additionally, systemic increase in acetate negatively affects humoral immune response, diminishing TFH cell as well as professional antigen-presenting cell (APC) function. Hence, alcohol consumption has profound effects on the efficacy of vaccinations, but also elicits protection against autoimmune diseases. The mechanism of alcohol's negative effects on the immune system is multivariate. Future studies addressing alcohol and its metabolite acetate's effect on individual components of the immune system remains crucial for our understanding and development of novel therapeutic pathways.

Body Habitus Across the Lifespan and Risk of Pituitary Adenoma

CONTEXT

No studies have examined the association between body habitus and incidence of pituitary adenoma.

OBJECTIVE

To determine if body mass index (BMI), waist circumference, body somatotype, or height are associated with risk of pituitary adenoma.

DESIGN

Pooled analysis of 3 prospective cohort studies.

SETTING

Population-based study.

PARTICIPANTS

Participants of the Nurses' Health Study (NHS), Nurses' Health Study II (NHSII), and the Health Professionals Follow-Up Study (HPFS), totaling 284 946 American health professionals.

EXPOSURES

BMI, waist circumference, body somatotype, and height.

OUTCOME MEASURES

Self-reported incident pituitary adenoma. Multivariable (MV)-adjusted hazard ratios (HRs) of pituitary adenoma were estimated using Cox proportional hazards models.

RESULTS

During 7 350 156 person-years of follow-up, 387 incident pituitary adenomas were reported. Comparing BMI of ≥30 to <25 kg/m2, higher adult BMI was associated with higher risk of pituitary adenoma (MV HR = 1.74; 95% CI, 1.33-2.28), as was higher maximum adult BMI (MV HR = 1.76; 95% CI, 1.34-2.30), higher waist circumference (MV HR = 1.06; 95% CI, 1.04-1.09 per inch), and higher BMI during early adulthood (at age 18 to 21, MV HR = 2.65; 95% CI, 1.56-4.49). Taller adult height was associated with pituitary adenoma (MV HR = 1.05; 95% CI, 1.01-1.09 per inch). Overall findings were similar in women and men, although power was limited in men (n = 62 cases). Sensitivity analyses demonstrated that the association between adult BMI and pituitary adenoma extended to at least 14 years prior to diagnosis and that the results were not affected when analyses were restricted to participants with similar healthcare utilization.

CONCLUSION

Higher BMI and waist circumference, from early adulthood to the time of diagnosis, were associated with higher risk of pituitary adenoma.

The effect of grape products containing polyphenols on oxidative stress: a systematic review and meta-analysis of randomized clinical trials

BACKGROUND

The literature showed that Grape Products Containing Polyphenols (GPCP) had anti-oxidant activity. However, the effects of GPCP on different biomarkers of oxidative stress are still controversial. In this regard, this systematic review and meta-analysis aimed to evaluate the effect of Grape Products Containing Polyphenols (GPCP) intake on oxidative stress markers.

METHODS

PubMed, Scopus, Web of Science, and Google Scholar data bases were searched up to August 20, 2020. A random-effects model, weighted mean difference (WMD), and 95% confidence interval (CI) were applied for data analysis. Meta-analysis was conducted over 17 eligible RCTs with a total of 633 participants. The study registration number is CRD42019116696.

RESULTS

A significant increase was observed in Total Antioxidant Capacity (TAC) (weighted mean difference (WMD) = 1.524 mmol/L, 95% confidence interval (CI): 0.83, 2.21). Intake of GPCP enhanced Superoxide Dismutase (SOD) (WMD = 0.450 mmol/L, 95% CI: 0.23, 0.66), TAC (WMD = 2.829 mmol/L, 95% CI: 0.13, 5.52), and Oxygen Radical Absorbance Capacity (ORAC) (WMD = 0.524 μmol/L, 95% CI: 0.42, 0.62) among healthy participants. Higher GPCP doses increased SOD (WMD = 0.539 U/mgHb, 95% CI: 0.24, 0.82) and ORAC (WMD = 0.377 μmol/L, 95% CI: 0.08, 0.67), whereas longer intervention periods enhanced ORAC (WMD = 0.543 μmol/L, 95% CI: 0.43, 0.64).

CONCLUSION

GPCP intake may partly improve status of oxidative stress, but further well-designed trials are required to confirm these results.

Posttraumatic Stress Disorder and Likelihood of Hormone Therapy Use among Women in the Nurses' Health Study II: A 26-Year Prospective Analysis

BACKGROUND

Posttraumatic stress disorder (PTSD) is associated with higher risk of certain chronic diseases, including ovarian cancer, but underlying mechanisms remain unclear. Although prior work has linked menopausal hormone therapy (MHT) use with elevated ovarian cancer risk, little research considers PTSD to likelihood of MHT use. We examined whether PTSD was prospectively associated with greater likelihood of initiating MHT use over 26 years.

METHODS

Using data from the Nurses' Health Study II, with trauma and PTSD (symptoms and onset date) assessed by screener in 2008 and MHT assessed via biennial survey (from 1989), we performed Cox proportional regression models with women contributing person-years from age 36 years. Relevant covariates were assessed at biennial surveys. We considered potential effect modification by race/ethnicity, age at baseline, and period (1989-2002 vs. 2003-2015).

RESULTS

Over follow-up, 22,352 of 43,025 women reported initiating MHT use. For example, compared with women with no trauma, the HR for initiating MHT was 1.18 for those with trauma/1-3 PTSD symptoms [95% confidence interval (CI), 1.13-1.22] and 1.31 for those with trauma/4-7 PTSD symptoms (95% CI, 1.25-1.36; P trend < 0.001), adjusting for sociodemographic factors. Associations were maintained when adjusting for reproductive factors and health conditions. We found evidence of effect modification by age at baseline.

CONCLUSIONS

Trauma and number of PTSD symptoms were associated with greater likelihood of initiating MHT use in a dose-response manner.

IMPACT

MHT may be a pathway linking PTSD to altered chronic disease risk. It is important to understand why women with PTSD initiate MHT use.

Diet in Rheumatoid Arthritis versus Systemic Lupus Erythematosus: Any Differences?

In recent years, an increasing interest in the influence of diet in rheumatic and musculoskeletal diseases (RMDs) led to the publication of several articles exploring the role of food/nutrients in both the risk of developing these conditions in normal subjects and the natural history of the disease in patients with established RMDs. Diet may be a possible facilitator of RMDs due to both the direct pro-inflammatory properties of some nutrients and the indirect action on insulin resistance, obesity and associated co-morbidities. A consistent body of research has been conducted in rheumatoid arthritis (RA), while studies in systemic lupus erythematosus (SLE) are scarce and have been conducted mainly on experimental models of the disease. This review article aims to outline similarities and differences between RA and SLE based on the existing literature.

The relationship between alcohol consumption and knee osteoarthritis in Korean population over 50 years-old: Results from Korea National Health and Nutrition Examination Survey

ABSTRACT

There is still debate regarding the pathogenic relationship between alcohol intake and osteoarthritis (OA). This study investigated the association between alcohol consumption and knee OA in a Korean population.Among 8058 subjects who participated in the Korea National Health and Nutrition Examination Survey (KNHANES) 2012, a total of 2917 subjects over the age of 50 and taken plain radiography was included in this analysis. Knee OA was classified based on the Kellgren-Lawrence (K-L) grading scale. Multivariate logistic regression analyses were used to evaluate the odds ratios (ORs) and 95% confidence intervals (CIs) of variables for knee OA (K-L grade ≥ 2).There were 1022 subjects with knee OA (29.2%). Subjects with knee OA tended to have lower daily alcohol intake (g/day) than did those without knee OA (10.4 [6.2-14.6] vs. 15.8 [12.8-18.8], P = .04). Similarly, those with knee OA demonstrated less makgeolli intake than did those without knee OA (P = .002). Subjects who consumed >0.6 g/day of beer also demonstrated less knee OA than did those who consumed <0.6 g/day of beer (OR 0.68, 95% CI 0.46-0.99). However, knee OA was not associated with the categories of alcohol consumption amount (g/day), including total daily alcohol intake (g/day), soju daily intake (g/day), and makgeolli daily intake (g/day) (P > .05 of all).Alcohol consumption was negatively associated with prevalence of knee OA in a Korean population. This preliminary observation will need to be confirmed in future studies.

Association between alcohol intake and the risk of systemic lupus erythematosus: A systematic review and meta-analysis

OBJECTIVES

Previous studies have reported inconsistent results on the relationship between alcohol intake and the risk of systemic lupus erythematosus (SLE). Therefore, we conducted a systematic review and meta-analysis to illustrate the potential role of alcohol intake on the progression of SLE.

METHODS

An electronic search of the PubMed, EmBase, and the Cochrane library databases was conducted from their inception up to March 2020. Observational studies that investigated the role of alcohol intake on the risk of SLE were eligible for inclusion in this study. The pooled odds ratio (OR) with 95% confidence interval (CI) was calculated as an effect estimate using the random-effects model.

RESULTS

Seven case-control studies (n = 3, 251) and three cohort studies (n = 322, 479) were selected for the final meta-analysis. Mild (OR: 0.85; 95% CI: 0.53-1.38; p = 0.515) or heavy (OR: 0.63; 95% CI: 0.37-1.09; p = 0.102) alcohol intake were not associated with the risk of SLE, while moderate alcohol intake could protect against the risk of SLE (OR: 0.71; 95% CI: 0.55-0.93; p = 0.012). Sensitivity analysis suggested that heavy alcohol intake was associated with a reduced risk of SLE (OR: 0.47; 95% CI: 0.32-0.67; p < 0.001).

CONCLUSIONS

This study found that moderate alcohol intake could protect against the risk of SLE, while mild or heavy alcohol intake did not significantly affect the risk of SLE.

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.

Abnormal thymic B cell activation and impaired T cell differentiation in pristane-induced lupus mice

Changes in the thymus and potential mechanisms underlying the pathogenesis in pristane-induced lupus (PIL) mice are poorly understood. This study aimed to systematically and specifically examine changes in the thymus and the potential mechanisms responsible for immunological abnormalities in PIL mice. The results showed that PIL mice exhibit serious thymic hyperplasia, an elevated thymus index, a damaged histopathological structure and increased thymocyte apoptosis. We found that thymic T cell differentiation was impaired as the CD4⁺ CD8⁺ double-positive (DP) thymocyte frequency significantly decreased, becoming almost absent at 28 weeks after induction, while CD4 CD8^- double-negative (DN) thymocytes and CD4⁺ CD8^- single-positive (CD4⁺ SP) and CD4 CD8⁺ single-positive (CD8⁺ SP) cells were increased. This phenomenon might be explained by an inhibition of the DN-to-DP-cell transition and stimulation of DP cell conversion into CD4⁺ /CD8⁺ SP thymocytes. Moreover, we discovered a dramatic and abnormal increase in thymic B cells, that was associated with CD19, Irf8, Ebf1, Pax5, Irf4, Blk, CXCL13, CXCR5, CD79a, CD79b, Lyn, Syk, Btk, and BLNK gene accumulation, which exhibited positive interactions. We further verified that the mRNA expression of these genes was significantly upregulated and consistent with the RNA-seq results. These results suggest a role of these genes in the increase of B cells in the thymus of PIL mice. In summary, our results showed the changes in the thymus in PIL and elucidated the immunologic abnormalities of increased B cells, potentially providing insight into the associated molecular mechanisms and facilitating further research.

Associations Between Smoking and Systemic Lupus Erythematosus-Related Cytokines and Chemokines Among US Female Nurses

OBJECTIVE

Smoking has been associated with increased systemic lupus erythematosus (SLE) risk, but the biologic basis for this association is unknown. Our objective was to investigate whether women's smoking was positively associated with SLE-associated proinflammatory chemokines/cytokines (stem cell factor [SCF], B lymphocyte stimulator [BLyS], interferon-γ-inducible 10-kd protein [IP-10], and interferon-α); or negatively associated with antiinflammatory cytokine interleukin-10 (IL-10); and whether associations were modified by SLE-related autoantibody status.

METHODS

The Nurses' Health Study (NHS, n = 121,700) and NHSII (n = 116,429) cohorts were begun in 1976 and 1989. In 1988-1990 (NHS) and 1996-1999 (NHSII), ~25% of participants donated blood samples. We identified 1,177 women without SLE with banked samples, and we tested by enzyme-linked immunoassay (ELISA) for chemokines/cytokines as well as anti-Sm, anti-Ro/SSA, anti-La/SSB, and anti-RNP. Antinuclear antibodies (ANAs) were detected by HEp-2 cell indirect immunofluorescence, and anti-double-stranded DNA antibodies and were assayed by ELISA. Smoking was assessed until blood draw. Separate tobit and linear regression analyses, adjusted for potential confounders, modeled associations between smoking and log-transformed chemokine/cytokine concentrations. Analyses were stratified by autoantibody status. Effect estimates were calculated as ratios of geometric means expressed as percentage differences.

RESULTS

Among the 15% of current/recent versus 85% of past/never smokers, BLyS levels were 8.7% higher (P < 0.01) and were 24% higher (P < 0.0001) among those who were ANA positive. Current/recent smokers had IL-10 concentrations 46% lower (P < 0.01) than past/never smokers; each 10 pack-years of smoking was associated with a 17% decrease in IL-10 level (P < 0.001). Smoking was not associated with IP-10 or SCF.

CONCLUSION

Elevated BLyS and lower IL-10 levels among current smokers, particularly among ANA-positive women, may be involved in SLE pathogenesis.

Associations between daily alcohol consumption and systemic lupus erythematosus-related cytokines and chemokines among US female nurses without SLE

OBJECTIVES

Moderate alcohol consumption has been associated with decreased systemic lupus erythematosus risk, but the biologic basis for this association is unknown. We aimed to determine whether moderate alcohol consumption was associated with lower concentrations of systemic lupus erythematosus-associated chemokines/cytokines in an ongoing cohort of female nurses without systemic lupus erythematosus, and whether the association was modified by the presence of systemic lupus erythematosus-related autoantibodies.

METHODS

About 25% of participants from the Nurses' Health Study (n = 121,700 women) and Nurses' Health Study 2 (n = 116,429) donated a blood sample; of these, 1177 women were without systemic lupus erythematosus at time of donation. Cumulative average and current (within 4 years) intakes of beer, wine or liquor were assessed from pre-blood draw questionnaires. Chemokine/cytokine concentrations (stem cell factor, B-lymphocyte stimulator, interferon-inducible protein-10, interferon-alpha, interleukin-10) and antibodies against dsDNA and extractable nuclear antigens were obtained using enzyme-linked immunosorbent assays. Antinuclear antibodies were detected by indirect immunofluorescence on HEp-2 cells.

RESULTS

At blood draw, the women's mean age was 56 years and 22% were antinuclear antibody positive; 36% were African-American. About half (46%) reported consuming 0-5 g/day of alcohol. Stem cell factor levels were 0.5% lower (p < 0.0001) for every gram per day increase in cumulative average alcohol consumption. Women who consumed >5 g/day had mean stem cell factor levels 7% lower (p = 0.002) than non-drinkers. Other cytokines were not significantly associated with alcohol intake. Autoantibody status did not modify observed associations.

CONCLUSION

In this study of female nurses, moderate alcohol consumption was associated with lower stem cell factor levels, suggesting a plausible mechanism through which alcohol may lower systemic lupus erythematosus risk might be by decreasing circulating stem cell factor.

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.

Ethanol consumption inhibits TFH cell responses and the development of autoimmune arthritis

Alcohol consumption is a consistent protective factor for the development of autoimmune diseases such as rheumatoid arthritis (RA). The underlying mechanism for this tolerance-inducing effect of alcohol, however, is unknown. Here we show that alcohol and its metabolite acetate alter the functional state of T follicular helper (T_FH) cells in vitro and in vivo, thereby exerting immune regulatory and tolerance-inducing properties. Alcohol-exposed mice have reduced Bcl6 and PD-1 expression as well as IL-21 production by T_FH cells, preventing proper spatial organization of T_FH cells to form T_FH:B cell conjugates in germinal centers. This effect is associated with impaired autoantibody formation, and mitigates experimental autoimmune arthritis. By contrast, T cell independent immune responses and passive models of arthritis are not affected by alcohol exposure. These data clarify the immune regulatory and tolerance-inducing effect of alcohol consumption.

Moderate consumption of alcohol is associated with protection from some autoimmune diseases. Here the authors show that ethanol and its metabolite acetate can protect mice from collagen-induced arthritis and provide evidence that the mechanism of this effect might be via inhibition of the effector function of T follicular helper cells.

Relationship of Cigarette Smoking and Alcohol Consumption to Incidence of Systemic Lupus Erythematosus in a Prospective Cohort Study of Black Women

OBJECTIVE

Systemic lupus erythematosus (SLE) affects black women more frequently than other racial/gender groups. In past studies, largely consisting of white and Asian cohorts, cigarette smoking was associated with increased SLE risk, and moderate alcohol consumption was associated with decreased SLE risk. The aim of this study was to assess associations of smoking and alcohol consumption with the risk of incident SLE among black women, using data from a long-term, prospective, follow-up study.

METHODS

The Black Women's Health Study enrolled 59,000 black women in 1995 and collected data on demographics, health status, and medical and lifestyle variables. Follow-up questionnaires that were given every 2 years identified incident disease and updated risk factors. Cases of incident SLE that met the American College of Rheumatology revised criteria for SLE as updated in 1997 were confirmed through medical record review. Cox regression models were used to estimate hazard ratios (HRs) and 95% confidence intervals (95% CI) for associations of cigarette smoking and alcohol intake with incidence of SLE.

RESULTS

A total of 127 incident SLE cases from 1995 to 2015 (mean age 43 years at diagnosis) were confirmed. Compared to never smokers, the risk of SLE among ever smokers was elevated, but not significantly (HR 1.45 [95% CI 0.97-2.18]). Risk was similar for current and past smoking and increased nonsignificantly with increasing pack-years. The HR was 0.71 (95% CI 0.45-1.12) for current drinking relative to never drinking, with a HR of 0.43 (95% CI 0.19-0.96) for ≥4 drinks/week.

CONCLUSION

Findings from this large study of SLE risk among black women are consistent with previous results from studies in other populations of increased risk of SLE associated with cigarette smoking and decreased risk with moderate alcohol consumption.

Dietary patterns and risk of systemic lupus erythematosus in women

OBJECTIVE

Dietary intake is a complex exposure and a potential risk factor for systemic lupus erythematosus (SLE) due to its impact on lipid and glucose metabolism, oxidative stress, and the intestinal microbiome. We aimed to test whether a prudent dietary pattern is associated with a lower risk of SLE, and whether a Western dietary pattern is associated with a higher risk of SLE.

METHODS

We prospectively investigated two dietary patterns and SLE risk among women in the Nurses' Health Study (NHS, 1984-2014) and Nurses' Health Study II (NHSII, 1991-2015). Food frequency questionnaires were completed every four years. Congruent with prior work in NHS and NHSII, we derived two separate dietary patterns (prudent and Western) using principal component analysis within each cohort. Incident SLE was confirmed by the American College of Rheumatology's 1997 criteria. We estimated hazard ratios (HR) and 95% confidence intervals (CI) for SLE by dietary pattern quartiles using Cox models adjusted for time-varying covariates. Models were performed separately in each cohort and results were meta-analyzed. Stratified analyses tested the association of dietary patterns with anti-dsDNA positive SLE and anti-dsDNA negative SLE.

RESULTS

We confirmed 82 NHS incident SLE cases and 98 NHSII SLE cases during 3,833,054 person-years of follow-up. A higher (healthier) prudent dietary pattern score was not associated with SLE risk (meta-analyzed HRQ4 versus Q1 0.84 [95% CI 0.51, 1.38]). Women with higher (less healthy) Western dietary pattern scores did not have a significantly increased risk for SLE (meta-analyzed HRQ4 versus Q1 1.35 [95% CI 0.77, 2.35]). Results were similar after further adjustment for body mass index. Incident anti-dsDNA positive SLE and anti-dsDNA negative SLE were not associated with either dietary pattern.

CONCLUSION

We did not observe a relationship between prudent or Western dietary pattern score and risk of SLE.

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.

Mimickers of neuropsychiatric manifestations in systemic lupus erythematosus

Systemic lupus erythematosus (SLE), presenting with new onset or worsening neuropsychiatric (NP) symptoms, is a challenge in clinical practice. Mimickers such as infections, drug-induced side effects, metabolic abnormalities, malignancies, and alcohol-related disorders have to be excluded, before attributing the manifestations to disease activity. Proper diagnosis is essential to guide adequate management and reduce morbidity and mortality. In this review article, we will highlight clinical, laboratorial, and neuroradiological features that are helpful to assist in the differential diagnosis.

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.

Alcohol intake and risk of systemic lupus erythematosus: a Mendelian randomization study

OBJECTIVES

This study aimed to examine whether alcohol intake is causally associated with systemic lupus erythematosus (SLE).

METHODS

We performed a two-sample Mendelian randomization (MR) analysis using the inverse-variance weighted (IVW), weighted median, and MR-Egger regression methods. We used the publicly available summary statistics of alcohol intake frequency from the UK Biobank genome-wide association studies (GWASs; n = 336,965) as the exposure and an SLE GWAS consisting of 1311 SLE and 1783 control subjects of European descent as the outcome.

RESULTS

We selected 20 single nucleotide polymorphisms (SNPs) associated with alcohol intake frequency at genome-wide significance as instrumental variables to improve inference. The IVW method found no evidence to support a causal association between alcohol intake and SLE (beta = -0.413, SE = 0.513, p = 0.421). The MR-Egger regression revealed that directional pleiotropy was unlikely to bias the result (intercept = 0.031, p = 0.582). The MR-Egger analysis found no causal association between alcohol intake and SLE (beta = -1.494, SE = 1.996, p = 0.464). Likewise, the weighted median approach also did not provide evidence of a causal association between alcohol intake and SLE (beta = -0.538, SE = 0.574, p = 0.349). The MR estimates determined using the IVW, weighted median, and MR-Egger regression methods were consistent and results from a "leave-one-out" analysis demonstrated that no single SNP was driving the IVW point estimate.

CONCLUSIONS

The results of MR analysis do not support a causal inverse association between alcohol intake and SLE occurrence.

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.

Cigarette smoking and the risk of systemic lupus erythematosus, overall and by anti-double stranded DNA antibody subtype, in the Nurses' Health Study cohorts

OBJECTIVES

Systemic lupus erythematosus (SLE) is a heterogeneous autoimmune disease, subtyped according to clinical manifestations and autoantibodies. Evidence concerning cigarette smoking and SLE risk has been conflicting. We investigated smoking and SLE risk, overall and by anti-double stranded DNA (dsDNA) presence, in two prospective cohort studies.

METHODS

The Nurses' Health Study (NHS) enrolled 121 701 US female nurses in 1976; Nurses' Health Study II (NHSII) enrolled 116 430 in 1989. Lifestyle, environmental and medical data were collected through biennial questionnaires. Incident SLE was confirmed by medical record review. Cox regression models estimated HRs of SLE, overall and by dsDNA subtype, in association with time-varying smoking status and cumulative smoking pack-years through the 2-year cycle prior to diagnosis, controlling for potential confounders.

RESULTS

Among 286 SLE cases identified (159 in NHS (1978-2012) and 127 in NHSII (1991-2013)), mean age was 49.2 (10.3) years and 42% were dsDNA+ at SLE diagnosis. At baseline, 45% of women had ever smoked, 51% of whom currently smoked. Compared with never smokers, current smokers had increased dsDNA+ SLE risk (HR 1.86 (1.14-3.04)), whereas past smokers did not (HR 1.31 (0.85-2.00)). Women who smoked >10 pack-years (vs never) had an elevated dsDNA+ SLE risk (HR 1.60(95% CI 1.04 to 2.45)) compared with never smokers. No associations were observed between smoking status or pack-years and overall SLE or dsDNA- SLE.

CONCLUSION

Strong and specific associations of current smoking and >10 pack-years of smoking with dsDNA+ SLE were observed. This novel finding suggests smoking is involved in dsDNA+ SLE pathogenesis.

Association of Trauma and Posttraumatic Stress Disorder With Incident Systemic Lupus Erythematosus in a Longitudinal Cohort of Women

OBJECTIVE

To conduct the first longitudinal study examining whether trauma exposure and posttraumatic stress disorder (PTSD) are associated with increased risk of incident systemic lupus erythematosus (SLE) in a civilian cohort.

METHODS

We examined the association of trauma exposure and PTSD symptoms with SLE incidence over 24 years of follow-up in a US longitudinal cohort of women (n = 54,763). Incident SLE in women meeting ≥4 American College of Rheumatology criteria was ascertained by self-report and confirmed by medical record review. PTSD and trauma exposure were assessed with the Short Screening Scale for Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition PTSD and the Brief Trauma Questionnaire, respectively. Women were categorized as having no trauma, trauma and no PTSD symptoms, subclinical PTSD (1-3 symptoms), or probable PTSD (4-7 symptoms). We examined whether longitudinally assessed health risk factors (e.g., smoking, body mass index [BMI], oral contraceptive use) accounted for increased SLE risk among women with trauma exposure and PTSD versus those without.

RESULTS

During follow-up, 73 cases of SLE occurred. Compared to women with no trauma, probable PTSD was associated with increased SLE risk (for 4-7 symptoms, hazard ratio [HR] 2.94 [95% confidence interval {95% CI} 1.19-7.26], P < 0.05). Subclinical PTSD was associated with increased SLE risk, although this did not reach statistical significance (for 1-3 symptoms, HR 1.83 [95% CI 0.74-4.56], P = 0.19). Smoking, BMI, and oral contraceptive use slightly attenuated the associations (e.g., for 4-7 symptoms, adjusted HR 2.62 [95% CI 1.09-6.48], P < 0.05). Trauma exposure, regardless of PTSD symptoms, was strongly associated with incident SLE (HR 2.83 [95% CI 1.29-6.21], P < 0.01).

CONCLUSION

This study contributes to growing evidence that psychosocial trauma and associated stress responses may lead to autoimmune disease.

Environmental exposures and the development of systemic lupus erythematosus

PURPOSE OF REVIEW

This review examines evidence relating environmental factors to the development of systemic lupus erythematosus (SLE).

RECENT FINDINGS

The strongest epidemiologic evidence exists for the associations of silica, cigarette smoking, oral contraceptives, postmenopausal hormone therapy and endometriosis, with SLE incidence. Recent studies have also provided robust evidence of the association between alcohol consumption and decreased SLE risk. There are preliminary, conflicting or unsubstantiated data that other factors, including air pollution, ultraviolet light, infections, vaccinations, solvents, pesticides and heavy metals such as mercury, are related to SLE risk. Biologic mechanisms linking environmental exposures and SLE risk include increased oxidative stress, systemic inflammation and inflammatory cytokine upregulation, and hormonal triggers, as well as epigenetic modifications resulting from exposure that could lead to SLE.

SUMMARY

Identifying the environmental risk factors related to risk of SLE is essential as it will lead to increased understanding of pathogenesis of this complex disease and will also make risk factor modification possible for those at increased risk.

Understanding the role of environmental factors in the development of systemic lupus erythematosus

Systemic lupus erythematosus (SLE) is a multisystem disease with a complex etiology. Its risk is higher among women, racial and ethnic minorities, and individuals with a family history of SLE or related autoimmune diseases. It is believed that genetic factors interact with environmental exposures throughout the lifespan to influence susceptibility to developing SLE. The strongest epidemiologic evidence exists for increased risk of SLE associated with exposure to crystalline silica, current cigarette smoking, use of oral contraceptives, and postmenopausal hormone replacement therapy, while there is an inverse association with alcohol use. Emerging research results suggest possible associations of SLE risk with exposure to solvents, residential and agricultural pesticides, heavy metals, and air pollution. Ultraviolet light, certain infections, and vaccinations have also been hypothesized to be related to SLE risk. Mechanisms linking environmental exposures and SLE include epigenetic modifications resulting from exposures, increased oxidative stress, systemic inflammation and inflammatory cytokine upregulation, and hormonal effects. Research needs to include new studies of environmental risk factors for SLE in general, with a focus on lifetime exposure assessment. In addition, studies in susceptible subgroups, such as family members, studies based on genetic risk profiles, and studies in individuals with evidence of pre-clinical autoimmunity based on the detection of specific auto-antibodies are also required. Understanding the role of environmental exposures in the development of SLE may help identify modifiable risk factors and potential etiological mechanisms.

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

BACKGROUND

Obesity is increasingly prevalent and related to increased risk of several autoimmune diseases, likely via generation of inflammatory adipokines. Prior studies have not evaluated obesity in relation to systemic lupus erythematosus (SLE) risk. We prospectively evaluated whether obesity was associated with increased SLE risk among women in the U.S. Nurses' Health Study cohorts.

METHODS

We conducted a prospective cohort study among 238,130 women in the Nurses' Health Studies (NHS, 1976-2012; NHSII, 1989-2013). Incident SLE was confirmed by American College of Rheumatology 1997 criteria and validated through medical record review. Body mass index (BMI, kg/m²) was calculated at baseline and on biennial questionnaires. Cox proportional hazards models estimated HRs (95% CIs) for SLE by cumulative average BMI category {18.5 to <25 [normal (reference)], 25 to <30 (overweight), ≥30 (obese)}, adjusting for potential time-varying confounders. Models were performed separately in each cohort; results were meta-analyzed. Sensitivity analyses used simple time-varying BMI, a 4-year lag between exposure and SLE risk window to address potential reverse causation, and evaluated BMI at age 18 and weight change since age 18. A secondary analysis started follow-up in both cohorts at similar calendar years when the prevalence of obesity in the U.S. increased most dramatically [1988 (NHS)/1989 (NHSII)].

RESULTS

We identified 153 NHS incident SLE cases and 115 incident NHSII cases during 5,602,653 person-years of follow-up. At baseline, 8.4% of women in NHS and 11.8% in NHSII were obese. Mean age at enrollment was 42.5 (SD 7.2) years in NHS and 34.4 (SD 4.7) years in NHSII. Cumulative average obesity was significantly associated with SLE risk in NHSII [HR = 1.85 (1.17-2.91)], but not in NHS [HR = 1.11 (0.65-1.87)] compared to normal BMI. In the meta-analysis of both cohorts, obesity was not significantly associated with increased risk of SLE [HR = 1.46 (0.88-2.40)]. Simple time-varying BMI and lagging the exposure window by 4 years produced similar findings to the primary analysis. In NHSII, a 4.54 kg gain between age 18 and enrollment slightly increased SLE risk [HR = 1.09 (1.02-1.18)]. In the secondary analysis starting follow-up of both cohorts at similar calendar years, the point estimate for obesity in NHS was higher than the primary analysis [HR = 1.67 (0.81-3.45)].

CONCLUSION

We observed an 85% significantly increased risk of SLE among obese compared to normal BMI women in the more recent NHSII cohort, but no association was observed in the earlier NHS cohort. Secular trends in obesity may account for the differences between the two birth cohorts.