Significant Reductions in Mortality in Hospitalized Patients with Systemic Lupus Erythematosus in Washington State from 2003 to 2011

Immune cells in skin inflammation, wound healing, and skin cancer

Given the self-evident importance of cutaneous immunity in the maintenance of body-surface homeostasis, disturbance of the steady-state skin is inextricably intertwined with dysfunction in cutaneous immunity. It is often overlooked by people that skin, well-known as a solid physical barrier, is also a strong immunological barrier, considering the abundant presence of immune cells including lymphocytes, granulocytes, dendritic cells, and macrophages. What's more, humoral immune components including cytokines, immunoglobulins, and antimicrobial peptides are also rich in the skin. This review centers on skin inflammation (acute and chronic, infection and aseptic inflammation), wound healing, and skin cancer to elucidate the elaborate network of immune cells in skin diseases.

Impact of severe infections in SLE: an observational study from the Spanish national registry

OBJECTIVE

Infections are a common complication of SLE. Our objective was to evaluate their causes and impact on the survival of patients with SLE.

METHODS

Analysis of the admissions and death causes in patients diagnosed with SLE from the Spanish Hospital Discharge Database and the infection-related deaths of the Spanish population from the National Statistical Institute, between 2016 and 2018.Only infections recorded as the main diagnosis were analysed (severe or clinically relevant infection).

RESULTS

Among 18 430 admissions in patients with SLE, disease activity was the cause of admission in 19% of all patients and infection in 15%. However, infection was the main cause of death (25%) while SLE activity was responsible for only 6% of deaths (p<0.001). Severe infection exceeded SLE as a cause of death for patients dying at ages between 40-59 (23% vs 4%, p<0.001), 60-79 (26% vs 6%, p<0.001) and older than 80 years (25% vs 6%, p<0.001). Infection was the cause of death in 8% of the Spanish population, a significantly lower rate when compared with patients with SLE (p<0.001). Compared with the general population, infections were the highest relative cause of death in patients with SLE, particularly at younger ages: 40% vs 3% for those below 20 years old (p<0.01), 33% vs 4% between 20 and 39 (p<0.001), 23% vs 5% between 40 and 59 (p<0.001), 26% vs 5% between 60 and 79 (p<0.001) and 25% vs 9% for those older than 80 years (p<0.001).

CONCLUSION

Our nationwide study confirms that infections are the leading cause of death in SLE in Spain, with the highest proportion occurring in young patients with lupus compared with the general population of the same age range.

Trends in Hospital Admissions and Death Causes in Patients with Systemic Lupus Erythematosus: Spanish National Registry

Background: the admission and death causes of SLE patients might have changed over the last years. Methods: Analysis of the Spanish National Hospital Discharge database. All individuals admitted with SLE, according to ICD-9, were selected. The following five admission categories were considered: SLE, cardiovascular disease (CVD), neoplasm, infection, and venous-thromboembolic disease (VTED), along four periods of time (1997–2000, 2001–2005, 2006–2010, and 2011–2015). Results: The admissions (99,859) from 43.432 patients with SLE were included. The absolute number of admissions increased from 15,807 in 1997–2000 to 31,977 in 2011–2015. SLE decreased as a cause of admission (from 47.1% to 20.8%, p < 0.001), while other categories increased over the time, as follows: 5% to 8.6% for CVD, 8.2% to 13% for infection, and 1.4% to 5.5% for neoplasm (p < 0.001 for all). The admission mortality rate rose from 2.22% to 3.06% (p < 0.001) and the causes of death evolved in parallel with the admission categories. A significant trend to older age was observed over time in the overall population and deceased patients (p < 0.001). Conclusions: Better control of SLE over the past two decades has led to a decrease in early admissions, and disease chronification. As a counterpart, CVD, infections, and neoplasm have become the main causes of admissions and mortality.

Mortality Among Hospitalized Individuals With Systemic Lupus Erythematosus in the US Between 2006 and 2016

OBJECTIVE

To evaluate time trends in mortality for hospitalized adults with systemic lupus erythematosus (SLE) compared to the general hospitalized population (GHP), and to identify factors associated with increased risk of death among hospitalized SLE patients.

METHODS

We used the National (Nationwide) Inpatient Sample to estimate all-cause mortality for adults discharged from community hospitals in the US between 2006 and 2016. Poisson regression models were used to estimate the risk of in-hospital death among all patients, including demographic characteristics, socioeconomic factors, comorbidity score, hospital region, SLE diagnosis, and race/ethnicity as covariates.

RESULTS

Among 340,467,049 hospitalizations analyzed, 1,903,279 had a discharge diagnosis of SLE. In adjusted analysis, the risk of inpatient death decreased among hospitalizations for patients with SLE from 2.2% to 1.5% (P < 0.001) between 2006 and 2016. All of the decrease in SLE mortality occurred between 2006 and 2008; after 2008, mortality stabilized at a rate statistically similar to the GHP. Hospitalizations for Black, Hispanic, and Asian/Pacific Islander patients with SLE were more likely to end in death compared to hospitalizations for either White patients with SLE or individuals of the same non-White race/ethnicity without SLE.

CONCLUSION

In the largest study of in-hospital SLE mortality published to date, we found significant improvements in mortality for hospitalized patients with SLE in the US from 2006 until 2008, after which mortality stabilized at a level similar to that of the GHP. Our results also demonstrate a persistently high mortality burden among Black and Hispanic patients with SLE in the US and contribute new data revealing high mortality among Asian/Pacific Islander patients with SLE.

Childhood-Onset Systemic Lupus Erythematosus: Southeast Asian Perspectives

Childhood onset systemic lupus erythematosus is a rare disease that is more common amongst Southeast Asian children compared to the West. It is typified by a peripubertal onset and a female preponderance, which increases with advancing age. Organs commonly involved at diagnosis include haematological, renal, and mucocutaneous. Fever, malar rash, and cutaneous vasculitis are common. Lupus nephritis is typically proliferative especially Class IV and contributes to both disease activity and damage. Antinuclear antibody and anti-dsDNA positivity are both prevalent in this region. Disease activity is higher than Western cohorts at onset but responds to therapy reducing to low disease activity by six months. However, organ damage occurs early and continues to accumulate over the time, a consequence of both active disease (neurological and renal systems) and steroid-related complications especially in the eye (cataract and glaucoma) and musculoskeletal systems (avascular necrosis). Infections remain the leading cause of death and mortality in this region is highly variable contributed by the heterogeneity in social economic status, healthcare access, and availability of paediatric rheumatology expertise in the region.

Reasons for Hospitalization and In-Hospital Mortality in Adult Systemic Lupus Erythematosus

OBJECTIVE

Systemic lupus erythematosus (SLE) is an autoimmune disease with an increased risk of hospitalization. Multiple studies have reported SLE flare, infection, and cardiovascular (CV) events as the most common reasons for hospitalization. The aim of this study was to use a large US population-based database to comprehensively analyze all indications for adult SLE hospitalization and reasons for in-hospital mortality.

METHODS

We conducted a retrospective study of SLE hospitalizations in 2017 from the National Inpatient Sample database. The "reason for hospitalization" and "reason for in-hospital mortality" in patients with SLE were divided into 19 categories based on their principal International Classification of Diseases, Tenth Revision, Clinical Modification (ICD-10) diagnosis.

RESULTS

A total of 180 975 hospitalizations carried either a principal or secondary ICD-10 code for SLE. The leading reasons for hospitalization were CV (16%), rheumatologic (13%), infectious (11%), respiratory (10%), and gastrointestinal (10%). SLE itself was the principal diagnosis in only 6% of the hospitalizations. In-hospital death occurred in 1 of every 50 SLE hospitalizations. Infectious (37%) and CV diagnoses (21%) were the most common reasons for in-hospital death, with sepsis being the most frequent reason for death.

CONCLUSION

This analysis represents the only report to date that comprehensively categorizes the reasons for hospitalization and reasons for in-hospital mortality of patients with SLE on a US national level. SLE itself was the principal diagnosis for only a small percentage of hospitalizations. CV diagnoses were the most common reason for hospitalization. In-hospital death occurred in 1 of every 50 SLE hospitalizations. Infectious and CV diagnoses were the most common reason for in-hospital death.

The Epidemiology and Outcomes of Mental Disorders in Critically Ill Patients With Systemic Lupus Erythematosus: A Population-Based Study

Background

Hospitalized patients with systemic lupus erythematosus (SLE) often require critical care, and SLE is the most common autoimmune disease in the intensive care unit (ICU). Mental disorders are highly prevalent among patients with SLE and are associated with increased morbidity and premature death in this population. However, the association of mental disorders with ICU utilization among patients with SLE and their prognostic impact among those admitted to ICU is unknown.

Methods

We performed a retrospective cohort study, using the Texas Inpatient Public Use Data File to identify SLE hospitalizations aged ≥ 18 years during 2009 - 2014. Mental disorders were defined by the taxonomy of the Healthcare Cost and Utilization Project’s Clinical Classification Software Category 5. The patterns of ICU admission among SLE hospitalizations with and without mental disorders were examined. Multivariable logistic regression modeling was used to examine the association of mental disorders and short-term mortality (defined as hospital death or discharge to hospice) among ICU admissions.

Results

Among 94,338 SLE hospitalizations 35,793 (37.9%) had mental disorders. There was no difference in the rates of ICU admission among SLE hospitalizations with and without mental disorders (37% vs. 37.2%, respectively; P = 0.5999), and similar rates of mental disorders were found among SLE hospitalizations with and without ICU admission (37.8% vs. 38%, respectively; P = 0.5408). The volume of SLE ICU admissions with and without mental disorders rose between 2009 and 2014 by 60.3% vs. 7.9%, respectively. When compared to those without mental disorders, SLE ICU admissions with mental disorders were older (age ≥ 65 years, 23.6% vs. 21.4%, respectively) and had higher burden of comorbid conditions. Unadjusted short-term mortality among SLE ICU admissions with and without mental disorders was 4.8% and 5.8%, respectively and mental disorders were associated with lower short-term mortality on adjusted analyses (adjusted odds ratio (aOR): 0.826; 95% confidence interval (CI): 0.734 - 0.930).

Conclusions

There was no difference in the frequency of mental disorders among hospitalized patients with SLE with and without ICU admission. However, the growth in the volume of ICU admissions with SLE over time involved predominantly patients with mental disorders. Among ICU admissions, mental disorders were associated with lower short-term mortality.

Epidemiology and outcomes of sepsis among hospitalizations with systemic lupus erythematosus admitted to the ICU: a population-based cohort study

Background

Sepsis is the most common cause of premature death among patients with systemic lupus erythematosus (SLE) aged ≤ 50 years in the United States, and infection is the most common cause of admission to the ICU among SLE patients. However, there are no population-level data on the patterns of the demand for critical care services among hospitalized septic patients with SLE or the outcomes of those admitted to the ICU.

Methods

We performed a retrospective cohort study, using the Texas Inpatient Public Use Data File, to identify SLE hospitalizations aged ≥ 18 years and the subgroups with sepsis and ICU admission during 2009–2014. The patterns of ICU admission among septic hospitalizations were examined. Logistic regression modeling was used to identify predictors of short-term mortality (defined as hospital death or discharge to hospice) among ICU admissions with sepsis and to estimate the risk-adjusted short-term mortality among ICU admissions with and without sepsis.

Results

Among 94,338 SLE hospitalizations, 17,037 (18.1%) had sepsis and 9409 (55.2%) of the latter were admitted to the ICU. Sepsis accounted for 51.5% of the growth in volume of ICU admissions among SLE hospitalizations during the study period. Among ICU admissions with sepsis, 25.3% were aged ≥ 65 years, 88.6% were female, and 64.4% were non-white minorities. The odds of short-term mortality among septic ICU admissions were increased among those lacking health insurance (adjusted odds ratio 1.40 [95% confidence interval 1.07–1.84]), while being unaffected by gender and race/ethnicity, and remaining unchanged over the study period. On adjusted analyses among ICU admissions, the short-term mortality among those with and without sepsis was 13% (95% CI 12.6–13.3) and 2.7% (95% CI 2.6–2.8), respectively. Sepsis was associated with 63.6% of all short-term mortality events.

Conclusions

Sepsis is a major, incremental driver of the demand for critical care services among SLE hospitalizations. Despite its relatively low mortality, sepsis was associated with most of the short-term deaths among ICU patients with SLE.

Trends of Hospital Palliative Care Utilization and Its Associated Factors Among Patients With Systemic Lupus Erythematosus in the United States From 2005 to 2014

OBJECTIVE

To investigate trends and associated factors of utilization of hospital palliative care among patients with systemic lupus erythematosus (SLE) and analyze its impact on length of hospital stay, hospital charges, and in-hospital mortality.

METHODS

Using the 2005-2014 National Inpatient Sample in the United States, the compound annual growth rate was used to investigate the temporal trend of utilization of hospital palliative care. Multivariate multilevel logistic regression analyses were performed to analyze the association with patient-related factors, hospital factors, length of stay, in-hospital mortality, and hospital charges.

RESULTS

The overall proportion of utilization of hospital palliative care for the patient with SLE was 0.6% over 10 years. It increased approximately 12-fold from 0.1% (2005) to 1.17% (2014). Hospital palliative care services were offered more frequently to older patients, patients with high severity illnesses, and in urban teaching hospitals or large size hospitals. Patients younger than 40 years, the lowest household income group, or Medicare beneficiaries less likely received palliative care during hospitalization. Hospital palliative care services were associated with increased length of stay (β = 1.407, P < .0001) and in-hospital mortality (odds ratio, 48.18; 95% confidence interval, 41.59-55.82), and reduced hospital charge (β = -0.075, P = .009).

CONCLUSION

Hospital palliative care service for patients with SLE gradually increased during the past decade in US hospitals. However, this showed disparities in access and was associated with longer hospital length of stay and higher in-hospital mortality. Nevertheless, hospital palliative care services yielded a cost-saving effect.

Global public interest in systemic lupus erythematosus: an investigation based on internet search data

Objective

This study aims at investigating the global public interest in seeking information about systemic lupus erythematosus (SLE) using Google Trends (GT).

Methods

An electronic search was performed using GT with the search term lupus as well as the option of disease from January 2004 to December 2018. Cosinor analysis was applied to detect the seasonality of SLE-related relative search volume (RSV). In addition, analysis on SLE-related topics including “hot topics” and “top rising topics” was also conducted.

Results

Overall, SLE-related RSV showed a decreasing trend from January 2004 to December 2013 and then demonstrated a slowly increasing trend from January 2014 to December 2018. Cosinor test showed no significant seasonal variation in SLE-related RSV ( p > .025). RSV peaked in May and reached the trough in November. The top seven rising topics were Selena Gomez, Sjögren syndrome, autoimmunity, rheumatoid arthritis, rheumatology, antinuclear antibody and autoimmune disease.

Conclusion

The results from GT analysis showed slowly increasing internet searches for SLE in recent years. This trend was followed by a peak of RSV in May and reached its lowest level in November. However, globally, the results did not reveal a significant seasonal variation in GT for SLE. Additionally, the top fast-growing topics regarding SLE may be valuable for doctors and nurses to provide timely education of the disease to patients, as well as promote the development of public health.

Trends in Maternal and Fetal Outcomes Among Pregnant Women With Systemic Lupus Erythematosus in the United States: A Cross-sectional Analysis

BACKGROUND

Although pregnancy in systemic lupus erythematosus (SLE) carries a high risk for mother and fetus, outcomes may be improving.

OBJECTIVE

To assess nationwide trends and disparities in maternal and fetal complications among pregnant women with SLE.

DESIGN

Retrospective cohort study.

SETTING

United States, 1998 to 2015.

PATIENTS

Adult pregnant women with and without SLE who had hospitalizations recorded in the National Inpatient Sample (NIS) database.

MEASUREMENTS

Outcome measures were in-hospital maternal mortality, fetal mortality, preeclampsia or eclampsia, caesarean sections, non-delivery-related admissions, and length of stay. To assess whether trends in outcomes over time differed between patients with SLE and those without SLE, logistic or linear regression with an interaction term between year and SLE (yes or no) was used. Nationwide population estimates incorporating sampling and poststratification weights were obtained.

RESULTS

An estimated 93 820 pregnant women with SLE and 78 045 054 without SLE were hospitalized in the United States from 1998 through 2015. Outcomes improved during those 18 years. In-hospital maternal deaths (per 100 000 admissions) declined among patients with as well as those without SLE (442 vs. 13 for 1998 to 2000 and <50 vs. 10 for 2013 to 2015), although the decrease was greater in women with SLE (difference in trends, P < 0.002). The percentage of patients with SLE in all pregnancy-related, as well as delivery-related, admissions increased significantly.

LIMITATIONS

The sample for this analysis was identified by using diagnostic codes; detailed information on hospital-specific trends, SLE disease activity, and medications was not available. Race trends could not be analyzed. Given that NIS uses weighted estimates, the incidence of outcomes reported may not be exact.

CONCLUSION

In this large study examining SLE and non-SLE pregnancies over 18 years, in-hospital maternal mortality and overall outcomes improved markedly, particularly among women with SLE. However, improvement is still needed, because SLE pregnancy risks remain high.

PRIMARY FUNDING SOURCE

None.

Causes and factors related to hospitalizations in patients with systemic lupus erythematosus: analysis of a 20-year period (1995-2015) from a single referral centre in Catalonia

INTRODUCTION

Although extensively characterized in the outpatient setting, systemic lupus erythematosus (SLE) in the hospitalization wards is still scarcely portrayed, particularly in the perspective of its evolution over the years.

METHODS

Retrospective analysis of SLE patients hospitalized in the Department of Autoimmune Diseases of a university hospital during a 20-year period (1995-2015), describing hospitalization characteristics, causes and predictors of outcome.

RESULTS

A total of 814 hospitalizations concerning 339 patients were analysed. The main causes of admission were flare (40.2%), infection (19.2%), diagnostic procedures (18.8%) and thrombotic events (5.4%). Therapy with cyclophosphamide (odds ratio (OR) 1.908, p = 0.047) was associated with admission due to infection, while antimalarials displayed a protective effect (OR 0.649, p = 0.024). Nearly 3.9% of patients required admission to an intensive care unit, with associated antiphospholipid syndrome (OR 7.385, p = 0.04) standing as a predicting factor for this outcome. Readmission at 30 days occurred in 5.8% of patients, with thrombocytopenia (OR 6.007, p = 0.002) and renal involvement (OR 3.362, p = 0.032) featuring as predicting factors. Eight patients died, with antiphospholipid syndrome (OR 26.814, p = 0.02) and thrombocytopenia (OR 31.523, p = 0.01) being associated with mortality. There was no significant variation in patients' demographics or admission causes across the 20-year period, except for a decrease in admissions due to thrombotic and musculoskeletal causes. Recently, an increase in the use of mycophenolate mofetil and lower doses of glucocorticoids were noted.

CONCLUSION

While demographics of SLE hospitalizations have not markedly changed over the past 20 years, changes in therapy patterns were observed. Thrombocytopenia, antiphospholipid syndrome and renal involvement featured as predictors of poor outcome.

All-cause hospitalizations in systemic lupus erythematosus from a single medical center in Israel

OBJECTIVE

Clinical features of systemic lupus erythematosus (SLE) have been described from different geographical regions in the world. The aim of this study was to obtain local and contemporary data on all-cause hospitalizations of SLE patients in an Israeli Medical Center.

METHODS

This is a retrospective observational single-center study. Revision of medical records of hospitalized lupus patients during 5-year period (January 2012-December 2016) was performed.

RESULTS

A total of 61 lupus patients and 138 hospitalizations were identified. Female-to-male ratio was 9:1. Average age was 42.5 years. Average disease duration was 14.58 years. Mean SLICC/ACR damage index was 0.75. The majority of patients were treated with lupus medications (47, 77%). The most common lupus medications were hydroxychloroquine (40, 65.5%), prednisone (25, 40.9%), and azathioprine (9, 14.75%). The most common reasons for hospitalization were disease flare (28, 20.3%), pregnancy and labor (26, 18.9%), and infection (19, 13.8%). The average length of hospitalization for all patients was 6.65 days. No fetal morbidity was recorded, and there was one event of maternal morbidity. There were no cases of acute coronary events. There were six ICU admissions (4.35%). Two admissions (1.45%) were complicated by hospital-acquired infection. Three patients died (2.17%) during hospital stay.

CONCLUSIONS

This survey from a single Israeli medical center revealed low rates of pregnancy complications, coronary events, and nosocomial infections in hospitalized lupus patients. Further studies are required to determine whether these findings reflect local disease expression or it may remark global trend of decrease in lupus complications.

GnRH Antagonist Improves Pubertal Cyclophosphamide-Induced Long-Term Testicular Injury in Adult Rats

BACKGROUND

Gonadal injury following chemotherapy is of increasing importance with the continuous improvement of survival rates. The protection of gonadotropin hormone antagonist (GnRHant) in long-term adult survivors of adolescent cancers and some autoimmune diseases has not yet been evaluated.

METHODS

The present study was aimed at longitudinally exploring whether the GnRHant could alleviate testicular damage induced by cyclophosphamide (CPA) in a rat model. Pubertal male rats were assigned to receive CPA with and without GnRHant. CPA was administrated at a single dose (100 mg/kg). GnRHant was started one hour prior to CPA injection and continued for four weeks (0.1 mg/kg, 3 times a week). Body and testes weights, testicular hormones, histological changes, and expression of androgen receptor (AR) in the testis were analyzed when rats matured into adulthood and completed a round of spermatogenesis.

RESULTS

Our results showed that body weight, histological injury, and AR expression in the testis were improved in the GnRHant + CPA group. However, testes weight and testicular hormones (anti-Müllerian hormone, inhibin B, and testosterone) did not markedly change.

CONCLUSION

Our results indicate that the GnRHant administration before and after CPA in pubertal rats can protect long-term testicular injury induced by CPA via increased AR expression in the testes.

Cardiovascular Disease Prevention Counseling Program for Systemic Lupus Erythematosus Patients

OBJECTIVE

To determine if a cardiovascular disease (CVD) prevention counseling program for lupus patients decreases the prevalence of CVD risk factors.

METHODS

The assessment phase of a 3-year CVD prevention counseling program included the evaluation of CVD risk factors, diet, exercise habits, and medications. The education phase included discussion of the above risk factors, as well as CVD and thrombosis prevention strategies. Patients were prospectively followed every 3-6 months for risk assessment and continued education by a nurse practitioner and a medical doctor.

RESULTS

Between March 2009 and December 2014, 121 patients were included. At baseline, abnormal blood pressure, blood glucose, cholesterol profile, and body mass index were found in 50 (41%), 7 (6%), 82 (68%), and 77 (64%) patients, respectively. During the 3-year followup, among those with abnormal baseline values, prevalence of abnormal blood pressure significantly decreased (odds ratio [OR] 0.94, 95% confidence interval [95% CI] 0.92-0.96, P < 0.0001) with significant mean ± SD systolic blood pressure improvement (-6.12 ± 2.16 mm Hg; P < 0.05). The prevalence of abnormal cholesterol profile significantly decreased (OR 0.90, 95% CI 0.92-0.96) with significant improvements in mean ± SD high-density lipoprotein (+5.4 ± 0.36 mg/dl; P < 0.0001) and triglyceride levels (-12.6 ± 5.40 mg/dl; P < 0.05), and no significant change in blood glucose and body mass index was observed. At baseline, 100 (83%) and 95 (79%) patients had poor diet and physical activity, respectively; during the followup, both significantly improved in the entire population.

CONCLUSION

Our data suggest that a CVD prevention counseling program decreases the prevalence of some CVD risk factors in lupus patients.

Effective Self-Management Interventions for Patients With Lupus: Potential Impact of Peer Mentoring

Systemic lupus erythematosus (SLE) is associated with significant mortality, morbidity and cost for the individual patient and society. In the United States, African Americans (AAs) have 3-4 times greater prevalence of lupus, risk of developing lupus at an earlier age and lupus-related disease activity, organ damage and mortality compared with whites. Evidence-based self-management interventions that incorporate both social support and health education have reduced pain, improved function and delayed disability among patients with lupus. However, AAs and women are still disproportionately affected by lupus. This article presents the argument that peer mentoring may be an especially effective intervention approach for AA women with SLE. SLE peers with a track record of success in lupus management and have a personal perspective that clinicians often lack. This commonality and credibility can establish trust, increase communication and, in turn, decrease disparities in healthcare outcomes.

Effect of Systemic Lupus Erythematosus on the Risk of Incident Respiratory Failure: A National Cohort Study

Purpose

We conducted a nationwide cohort study to investigate the relationship between systemic lupus erythematosus (SLE) and the risk of incident respiratory failure.

Methods

From the National Health Insurance Research Database, we identified 11 533 patients newly diagnosed with SLE and 46 132 controls without SLE who were randomly selected through frequency-matching according to age, sex, and index year. Both cohorts were followed until the end of 2011 to measure the incidence of incident respiratory failure, which was compared between the 2 cohorts through a Cox proportional hazards regression analysis.

Results

The adjusted hazard ratio (aHR) of incident respiratory failure was 5.80 (95% confidence interval [CI] = 5.15–6.52) for the SLE cohort after we adjusted for sex, age, and comorbidities. Both men (aHR = 3.44, 95% CI = 2.67–4.43) and women (aHR = 6.79, 95% CI = 5.93–7.77) had a significantly higher rate of incident respiratory failure in the SLE cohort than in the non-SLE cohort. Both men and women aged <35 years (aHR = 31.2, 95% CI = 21.6–45.2), 35–65 years; (aHR = 6.19, 95% CI = 5.09–7.54) and ≥65 years (aHR = 2.35, 95% CI = 1.92–2.87) had a higher risk of incident respiratory failure in the SLE cohort. Moreover, the risk of incident respiratory failure was higher in the SLE cohort than the non-SLE cohort, for subjects with (aHR = 2.65, 95% CI = 2.22–3.15) or without (aHR = 9.08, 95% CI = 7.72–10.7) pre-existing comorbidities. In the SLE cohort, subjects with >24 outpatient visits and hospitalizations per year had a higher incident respiratory failure risk (aHR = 21.7, 95% CI = 18.0–26.1) compared with the non-SLE cohort.

Conclusion

Patients with SLE are associated with an increased risk of incident respiratory failure, regardless of their age, sex, and pre-existing comorbidities; especially medical services with higher frequency.