Post-Traumatic Stress Disorder and Risk for Incident Rheumatoid Arthritis

Distinguishing vulnerability and resilience to posttraumatic stress disorder evaluating traumatic experiences, genetic risk and electronic health records

What distinguishes vulnerability and resilience to posttraumatic stress disorder (PTSD) remains unclear. Levering traumatic experiences reporting, genetic data, and electronic health records (EHR), we investigated and predicted the clinical comorbidities (co-phenome) of PTSD vulnerability and resilience in the UK Biobank (UKB) and All of Us Research Program (AoU), respectively. In 60,354 trauma-exposed UKB participants, we defined PTSD vulnerability and resilience considering PTSD symptoms, trauma burden, and polygenic risk scores. EHR-based phenome-wide association studies (PheWAS) were conducted to dissect the co-phenomes of PTSD vulnerability and resilience. Significant diagnostic endpoints were applied as weights, yielding a phenotypic risk score (PheRS) to conduct PheWAS of PTSD vulnerability and resilience PheRS in up to 95,761 AoU participants. EHR-based PheWAS revealed three significant phenotypes positively associated with PTSD vulnerability (top association "Sleep disorders") and five outcomes inversely associated with PTSD resilience (top association "Irritable Bowel Syndrome"). In the AoU cohort, PheRS analysis showed a partial inverse relationship between vulnerability and resilience with distinct comorbid associations. While PheRSvulnerability associations were linked to multiple phenotypes, PheRSresilience showed inverse relationships with eye conditions. Our study unveils phenotypic differences in PTSD vulnerability and resilience, highlighting that these concepts are not simply the absence and presence of PTSD.

Risk factors and consequences of mental health problems in nurses: A scoping review of cohort studies

Mental health problems in nurses are prevalent and impairing. To date, no literature has comprehensively synthesised cohort evidence on mental health among nurses. This scoping review aimed to synthesise the existing literature on the risk factors and consequences of mental health problems in nurses. A systematic search was conducted on PubMed, EMBASE, Epistemonikos database, Web of Science, CINAHL, and PsycINFO from inception to March 2023. We identified 171 cohort studies from 16 countries, mostly (95.3%) from high-income economies. This review indicated that nurses worldwide encountered significant mental health challenges, including depression, cognitive impairment, anxiety, trauma/post-traumatic stress disorder, burnout, sleep disorder, and other negative mental health problems. These problems were closely related to various modifiable risk factors such as nurses' behaviours and lifestyles, social support, workplace bullying and violence, shift work, job demands, and job resources. Moreover, nurses' mental health problems have negative effects on their physical health, behaviour and lifestyle, occupation and organisation, and intrapersonal factors. These findings provided an enhanced understanding of mental health complexities among nurses, and shed light on policy enactment to alleviate the negative impact of mental health problems on nurses. Addressing mental health among nurses should be a top priority.

How the Plants for Joints multidisciplinary lifestyle intervention achieved its effects: a mixed methods process evaluation

BACKGROUND

Plants for Joints (PFJ) is a multidisciplinary intervention centered around a whole-food plant-based diet, physical activity, and sleep and stress management. The PFJ intervention successfully improved disease activity and symptoms in people with rheumatoid arthritis (RA) or osteoarthritis (OA), respectively, and metabolic health. To investigate how these effects were achieved a mixed methods process evaluation was conducted to understand the context, implementation, and mechanism of impact of the PFJ intervention. Also, the relationship between degree of implementation and lifestyle changes was explored.

METHODS

Quantitative and qualitative data were collected across the evaluation domains context (i.e. reach), implementation (i.e. recruitment and delivery), and mechanism of impact (i.e. responsiveness) of both the participants and coaches (incl. dietitians, sport coaches) according to the UK MRC guidelines for process evaluations. Data was collected from the participants via focus groups and questionnaires after the intervention, and interviews with coaches. Qualitative data were analyzed thematically, and quantitative data were assessed with descriptive statistics and linear regression analyses. Degree of implementation was quantified using a theory-driven implementation index score composed of different process evaluation constructs.

RESULTS

Of the 155 participants who participated in the PFJ intervention, 106 (68%) took part in the questionnaire and 34 (22%) attended a focus group. Participants felt the intervention was complete, coherent, and would recommend the intervention to others (mean score 9.2 (SD 1.4) out of 10). Participants felt heard and empowered to take control of their lifestyle and health outcomes. Components perceived as most useful were self-monitoring, social support, practical and theoretical information, and (individual) guidance by the multidisciplinary team. Participants perceived the intervention as feasible, and many indicated it effectively improved their health outcomes. In an explorative analysis there was no significant difference in healthy lifestyle changes across implementation index score groups.

CONCLUSION

This process evaluation offers important insights into why the PFJ intervention works and how the intervention can be optimized for future implementation. Results indicating the intervention's high satisfaction, feasibility, and perceived effectiveness, further support the use of plant-based lifestyle interventions as an additional treatment option for patients with RA, OA, or other chronic diseases.

TRIAL REGISTRATION

International Clinical Trial Registry Platform numbers: NL7800, NL7801, and NL7802, all registered 17-06-2019.

Effects of genetically predicted posttraumatic stress disorder on autoimmune phenotypes

Observational studies suggest that posttraumatic stress disorder (PTSD) increases risk for various autoimmune diseases. Insights into shared biology and causal relationships between these diseases may inform intervention approaches to PTSD and co-morbid autoimmune conditions. We investigated the shared genetic contributions and causal relationships between PTSD, 18 autoimmune diseases, and 3 immune/inflammatory biomarkers. Univariate MiXeR was used to contrast the genetic architectures of phenotypes. Genetic correlations were estimated using linkage disequilibrium score regression. Bi-directional, two-sample Mendelian randomization (MR) was performed using independent, genome-wide significant single nucleotide polymorphisms; inverse variance weighted and weighted median MR estimates were evaluated. Sensitivity analyses for uncorrelated (MR PRESSO) and correlated horizontal pleiotropy (CAUSE) were also performed. PTSD was considerably more polygenic (10,863 influential variants) than autoimmune diseases (median 255 influential variants). However, PTSD evidenced significant genetic correlation with nine autoimmune diseases and three inflammatory biomarkers. PTSD had putative causal effects on autoimmune thyroid disease (p = 0.00009) and C-reactive protein (CRP) (p = 4.3 × 10-7). Inferences were not substantially altered by sensitivity analyses. Additionally, the PTSD-autoimmune thyroid disease association remained significant in multivariable MR analysis adjusted for genetically predicted inflammatory biomarkers as potential mechanistic pathway variables. No autoimmune disease had a significant causal effect on PTSD (all p values > 0.05). Although causal effect models were supported for associations of PTSD with CRP, shared pleiotropy was adequate to explain a putative causal effect of CRP on PTSD (p = 0.18). In summary, our results suggest a significant genetic overlap between PTSD, autoimmune diseases, and biomarkers of inflammation. PTSD has a putative causal effect on autoimmune thyroid disease, consistent with existing epidemiologic evidence. A previously reported causal effect of CRP on PTSD is potentially confounded by shared genetics. Together, results highlight the nuanced links between PTSD, autoimmune disorders, and associated inflammatory signatures, and suggest the importance of targeting related pathways to protect against disease and disability.

Risk of autoimmune diseases after post-traumatic stress disorder: a nationwide cohort study

This longitudinal study aimed to investigate the risk of subsequent autoimmune disease in patients with post-traumatic stress disorder (PTSD) in Asian population. Between 2002 and 2009, we enrolled 5273 patients with PTSD and 1:4 matched controls from the National Health Insurance Database of Taiwan, and followed up the patients until December 31, 2011, or death. The investigated autoimmune diseases included thyroiditis, lupus, rheumatic arthritis, inflammatory bowel disease, Sjogren's syndrome, dermatomyositis, and polymyositis. The Cox regression model was used to estimate the risk of developing autoimmune diseases, with adjustment for demographics and psychiatric and medical comorbidities. Furthermore, we examined the psychiatric clinics utility of patients with PTSD indicating the severity of PTSD in association with autoimmune diseases. After adjusting for confounders, patients with PTSD had a 2.26-fold higher risk of developing any autoimmune diseases (reported as hazard ratios with 95% confidence intervals: 1.82-2.80) than the controls. For specific autoimmune diseases, patients with PTSD had a 2.70-fold higher risk (1.98-3.68) of thyroiditis, a 2.95-fold higher risk (1.20-7.30) of lupus, and a 6.32-fold higher risk (3.44-11.60) of Sjogren's syndrome. Moreover, the PTSD severity was associated with the risk of autoimmune diseases in a dose-dependent manner. The patient with the highest psychiatric clinics utility was associated with an 8.23-fold higher risk (6.21-10.90) of any autoimmune diseases than the controls. Patients with PTSD had an increased risk of autoimmune diseases, and such risk was associated with the severity of PTSD in a dose-dependent manner. However, the present study did not provide a direct effect between PTSD and autoimmune diseases, but rather an association. Further studies are warranted to examine the underlying pathophysiological mechanisms.

Posttraumatic stress disorder symptoms in systemic autoimmune rheumatic disease patients during the early COVID-19 pandemic

AIM

Given reports of increased prevalence of PTSD symptoms at COVID-19 pandemic onset, we aimed to assess the prevalence of posttraumatic stress disorder (PTSD) symptoms at pandemic onset in individuals with and without systemic autoimmune rheumatic disease (SARD).

METHODS

In May 2020, we invited 6678 patients to complete the Brief Trauma Questionnaire and the Posttraumatic Stress Disorder Checklist (PCL-5), validated PTSD symptom screenings. We compared responses from patients with and without SARD using multivariable logistic regression.

RESULTS

We received 1473 responses (22% response rate) from 5/2020 to 9/2021 (63 with prior PTSD diagnoses, 138 with SARD history). The SARD population was more female (p .0001) and had a higher baseline prevalence of stress disorders (56% vs. 43%, p .004). SARD subjects reported more experiences with life-threatening illness, 60%, versus 53% among those without SARD (p .13), and more antidepressant or anxiolytic medication use pre-pandemic (78% vs. 59%, p .0001). Adjusting for pre-pandemic PTSD diagnosis, younger age and history of stress disorder were the most significant predictors of PCL-5 positivity. There were no significant differences in PCL-5 score or positivity among those with or without SARD.

CONCLUSION

In this population, patients with SARD had a higher pre-COVID-19 prevalence of stress-related conditions, but it was not the case that they had an increased risk of PTSD symptoms in the early pandemic. Younger individuals, those with baseline depression, anxiety, or adjustment disorders, and those taking antidepressant or anxiolytic medications were more likely to have PTSD symptoms in the first waves of the COVID-19 pandemic.

Life Events, Caregiving, and Risk of Autoimmune Rheumatic Diseases in the Women's Health Initiative Observational Study

OBJECTIVE

Growing evidence suggests psychosocial stressors may increase risk of developing autoimmune disease. We examined stressful life events and caregiving in relation to incident rheumatoid arthritis (RA) and systemic lupus erythematosus (SLE) in the Women's Health Initiative Observational Study cohort.

METHODS

The sample of postmenopausal women included 211 incident RA or SLE cases reported within 3 years after enrollment, confirmed by use of disease-modifying antirheumatic drugs (i.e., probable RA/SLE), and 76,648 noncases. Baseline questionnaires asked about life events in the past year, caregiving, and social support. We used Cox regression models to calculate hazard ratios (HR) and 95% confidence intervals (95% CIs), adjusting for age, race/ethnicity, occupational class, education, pack-years of smoking and BMI.

RESULTS

Incident RA/SLE was associated with reporting 3 or more life events (e.g., age-adjusted HR 1.70 [95% CI 1.14, 2.53]; P for trend = 0.0026). Elevated HRs were noted for physical (HR 2.48 [95% CI 1.02, 6.04]) and verbal (HR 1.34 [0.89, 2.02]) abuse (P for trend = 0.0614), 2 or more interpersonal events (HR 1.23 [95% CI 0.87, 1.73]; P for trend = 0.2403), financial stress (HR 1.22 [95% CI 0.90, 1.64]), and caregiving 3 or more days per week (HR 1.25 [95% CI 0.87, 1.81]; P for trend = 0.2571). Results were similar, excluding women with baseline symptoms of depression or moderate-to-severe joint pain in the absence of diagnosed arthritis.

CONCLUSION

Our findings support the idea that diverse stressors may increase risk of developing probable RA or SLE in postmenopausal women, supporting the need for further studies in autoimmune rheumatic diseases, including childhood adverse events, life event trajectories, and modifying psychosocial and socioeconomic factors.

S100a9 Protects Against the Effects of Repeated Social Defeat Stress

Background

Posttraumatic stress disorder, a consequence of psychological trauma, is associated with increased inflammation and an elevated risk of developing comorbid inflammatory diseases. However, the mechanistic link between this mental health disorder and inflammation remains elusive. We previously found that S100a8 and S100a9 messenger RNA, genes that encode the protein calprotectin, were significantly upregulated in T lymphocytes and positively correlated with inflammatory gene expression and the mitochondrial redox environment in these cells. Therefore, we hypothesized that genetic deletion of calprotectin would attenuate the inflammatory and redox phenotype displayed after psychological trauma.

Methods

We used a preclinical mouse model of posttraumatic stress disorder known as repeated social defeat stress (RSDS) combined with pharmacological and genetic manipulation of S100a9 (which functionally eliminates calprotectin). A total of 186 animals (93 control, 93 RSDS) were used in these studies.

Results

Unexpectedly, we observed worsening of behavioral pathology, inflammation, and the mitochondrial redox environment in mice after RSDS compared with wild-type animals. Furthermore, loss of calprotectin significantly enhanced the metabolic demand on T lymphocytes, suggesting that this protein may play an undescribed role in mitochondrial regulation. This was further supported by single-cell RNA sequencing analysis demonstrating that RSDS and loss of S100a9 primarily altered genes associated with mitochondrial function and oxidative phosphorylation.

Conclusions

These data demonstrate that the loss of calprotectin potentiates the RSDS-induced phenotype, which suggests that its observed upregulation after psychological trauma may provide previously unexplored protective functions.

Posttraumatic Stress Disorder, Depression, and Accelerated Aging: Leukocyte Telomere Length in the Nurses' Health Study II

Background

Exposure to trauma, posttraumatic stress disorder (PTSD), and depression have been independently associated with leukocyte telomere length (LTL), a cellular marker of aging associated with mortality and age-related diseases. However, the joint contributions of trauma and its psychological sequelae on LTL have not been examined.

Methods

We conducted an analysis of LTL in a subset of women from the Nurses' Health Study II (N = 1868). Lifetime exposure to traumatic events, PTSD, and depression was assessed with validated measures. DNA was extracted from peripheral blood leukocytes and telomere repeat copy number to single gene copy number was determined by quantitative real-time polymerase chain reaction telomere assay. Linear regression models assessed the association of trauma, PTSD, and depression with LTL after adjustment for health behaviors and medical conditions.

Results

Trauma, PTSD, and depression were not independently associated with LTL in mutually adjusted models. However, individuals with severe psychological distress-characterized by comorbid PTSD and depression-had shorter LTL equivalent to being 7.62 years older (95% CI, 0.02 to 17.97) than participants who had never experienced a traumatic event and were not depressed. Further examination found only an association among individuals with the highest number of PTSD symptoms and comorbid depression equivalent to 9.71 additional years of aging (95% CI, 1.36 to 20.49). No effect was found among individuals meeting the minimum threshold for probable PTSD with comorbid depression.

Conclusions

Severe psychological distress, as indicated by the presence of comorbid PTSD and depression, may be associated with shorter LTL.

Post-traumatic stress disorder prior to diagnosis is as rare in spondyloarthritis as in non-inflammatory rheumatic conditions and rheumatoid arthritis

OBJECTIVE

Post-traumatic stress disorder (PTSD) may be a risk factor for the development of rheumatoid arthritis (RA). No data are available in spondyloarthritis (SpA). The aim of the present study was to investigate the frequency of traumatic events and PTSD in patients with SpA and its different phenotypes and to compare the results to patients with non inflammatory rheumatic disease and RA patients.

METHODS

This was an observational, cross-sectional and bi-centric study. Participants were patients diagnosed with SpA, non-inflammatory rheumatic or autoimmune disease (controls), or RA. Traumatic events were identified by the brief trauma questionnaire (BTQ). PTSD was defined as the presence of a traumatic event and ≥4 symptoms on the short PTSD checklist scale.

RESULTS

Among 1389 participants, 510 patients were diagnosed with SpA (167 ankylosing spondylitis, 140 psoriatic arthritis, 130 non-radiographic-axial SpA, and 51 peripheral SpA), 365 with non-inflammatory rheumatic disease and 514 patients with RA. The frequency of trauma in SPA patients was 33.7%, of which 30.5% in AS, 30.7% in PsA, 37.7% in nr-axSpA and 41.2% in peripheral SpA (P=NS). The prevalence of PTSD in SPA patients was 4.9%, (of which 3.6% in AS, 2.9% in PsA, 6.2% in nr-axSpA and 7.8% in peripheral SpA [P=NS]) and was not significantly different from the controls (after IPTW 4.8% vs. 6.7%). The frequency of trauma and PTSD was also comparable between RA and controls and between SPA and RA.

CONCLUSION

Traumatic events and PTSD occurring prior to diagnosis is as rare in SpA as in non-inflammatory rheumatic diseases and RA.

Are We on the Same Page? A Cross-Sectional Study of Patient-Clinician Goal Concordance in Rheumatoid Arthritis

OBJECTIVE

Patient-clinician goal concordance is associated with improved outcomes in certain chronic diseases but not explored in rheumatoid arthritis (RA). We examined goal concordance, correlates of concordance, and the association of concordance with health outcomes.

METHODS

Adult patients with RA seen at least 1 time in the prior 12 months at 1 of 2 rheumatology clinics participated. Patients and their clinicians independently ranked top 3 goals for RA treatment from 8 options before a routine visit. Patients completed postvisit surveys on health, demographic information, health literacy, and adherence. Goal concordance was defined as the patient's number 1 goal being among the clinician's top 3 goals for that patient. Bivariable and multivariable logistic regression models were used to examine correlates of concordance.

RESULTS

Patients were 58% female and 16% Spanish-speaking, and 29% had limited health literacy. Among 204 patient-clinician dyads, 20% were goal-discordant. "Have less pain" was selected by both patient and clinician in 81% of dyads, followed by "have fewer problems doing daily activities" by 63%. Otherwise, clinicians prioritized avoiding side effects, whereas patients ranked improved sleep, fatigue, and mood. Longer disease duration was associated with discordance (median 13.3 years, interquartile range [IQR] 5.2-20 among discordant vs. 7 years, IQR 4-14; P = 0.039); higher depressive symptoms were associated with concordance (8.1% vs. 24%; P = 0.04). Goal concordance was associated with higher medication adherence (adjusted odds ratio 2.76 [95% confidence interval 1.01, 7.56]).

CONCLUSION

One in 5 patient-clinician dyads had discordant treatment goals. Goal concordance was associated with higher medication adherence. Studies to improve goal elicitation and communication of patients with RA's priorities are needed.

Association of Rheumatoid Arthritis with Opioid Pain Medication Overuse among Persons Exposed to the 9/11 World Trade Center Disaster

We examined the association of post-9/11 rheumatoid arthritis (RA) diagnosis with opioid pain medication overuse among enrollees in the World Trade Center Health Registry (WTCHR). Opioid overuse was defined as the self-reported intake of prescribed opioids at a higher dosage or more often than directed in the last 12 months on one of the two most recent WTCHR surveys (2015-2016, 2020-2021). Post-9/11 RA was ascertained through self-reports and subsequently validated following medical record release by the enrollees' physicians or medical records review. We excluded those with self-reported RA that was not validated by their physicians and those who did not report being prescribed opioid pain medication in the last 12 months. Multivariable log-binomial regression was conducted to examine the relationship between post-9/11 RA diagnosis and opioid pain medication overuse, adjusting for sociodemographic characteristics and 9/11-related posttraumatic stress disorder (PTSD) symptoms. Of the 10,196 study enrollees, 46 had confirmed post-9/11 RA. The post-9/11 RA patients were mostly females (69.6% vs. 37.7%), less frequently non-Hispanic White (58.7% vs. 73.2%) individuals, and less often had attained a higher level of education (76.1% vs. 84.4%) compared to those without post-9/11 RA. Opioid pain medication overuse was significantly associated with a post-9/11 RA diagnosis (Adjusted Risk Ratio: 2.13, 95% CI: 1.44-3.17). More research is needed to better understand the use and management of prescribed opioids among WTC-exposed individuals with RA.

The exposome in rheumatoid arthritis

The exposome integrates the variety and accumulation of exposures (external and internal) to which an individual is submitted to from conception to death. Exposome may therefore be a useful tool for understanding the diversity of these factors and their role in the pathophysiology of rheumatoid arthritis (RA). Life is perceived as a continuum of cumulative changes, with key periods of disruption (e.g. birth, adolescence, pregnancy, prolonged treatment). The combination of these changes and the external signals that cause them constitute an individual's exposome, which is constantly changing and expanding throughout life. Thus, measuring the exposome requires specific tools and approaches as well as a global perspective. RA, a complex, heterogeneous, pro-inflammatory autoimmune disease with a genetic component and for which a large number of environmental factors have already been incriminated is an appropriate field of application for the exposome. The aim of this review is to define the exposome concept, outline the different analytic tools available for its study and finally apply them to the field of RA.

Early onset of immune-mediated diseases in minority ethnic groups in the UK

BACKGROUND

The prevalence of some immune-mediated diseases (IMDs) shows distinct differences between populations of different ethnicities. The aim of this study was to determine if the age at diagnosis of common IMDs also differed between different ethnic groups in the UK, suggestive of distinct influences of ethnicity on disease pathogenesis.

METHODS

This was a population-based retrospective primary care study. Linear regression provided unadjusted and adjusted estimates of age at diagnosis for common IMDs within the following ethnic groups: White, South Asian, African-Caribbean and Mixed-race/Other. Potential disease risk confounders in the association between ethnicity and diagnosis age including sex, smoking, body mass index and social deprivation (Townsend quintiles) were adjusted for. The analysis was replicated using data from UK Biobank (UKB).

RESULTS

After adjusting for risk confounders, we observed that individuals from South Asian, African-Caribbean and Mixed-race/Other ethnicities were diagnosed with IMDs at a significantly younger age than their White counterparts for almost all IMDs. The difference in the diagnosis age (ranging from 2 to 30 years earlier) varied for each disease and by ethnicity. For example, rheumatoid arthritis was diagnosed at age 49, 48 and 47 years in individuals of African-Caribbean, South Asian and Mixed-race/Other ethnicities respectively, compared to 56 years in White ethnicities. The earlier diagnosis of most IMDs observed was validated in UKB although with a smaller effect size.

CONCLUSION

Individuals from non-White ethnic groups in the UK had an earlier age at diagnosis for several IMDs than White adults.

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.

The Relationship between 9/11 Exposure, Systemic Autoimmune Disease, and Post-Traumatic Stress Disorder: A Mediational Analysis

The relationship between 9/11 exposure, systemic autoimmune disease (SAD) and mental health remains poorly understood. This report builds on a prior analysis of World Trade Center Health Registry data to determine whether 9/11 exposure is associated with higher risk of SAD, and if so, whether post-traumatic stress disorder (PTSD) is a mediating factor and whether the association varies by responder/community member status. The final analytic sample comprised 41,656 enrollees with 123 cases of SAD diagnosed post 9/11 through November 2017. SAD diagnosis was ascertained from survey responses and confirmed by medical record review or physician survey. Logistic regression models were constructed to determine the relationship between 9/11 exposure and PTSD and SAD. Causal mediation analysis was used to determine the mediational effect of PTSD. Each analysis was stratified by 9/11 responder/community member status. Rheumatoid arthritis (n = 75) was the most frequent SAD, followed by Sjögren’s syndrome (n = 23), systemic lupus erythematosus (n = 20), myositis (n = 9), mixed connective tissue disease (n = 7), and scleroderma (n = 4). In the pooled cohort, those with 9/11-related PTSD had 1.85 times the odds (95% CI: 1.21–2.78) of SAD. Among responders, those with dust cloud exposure had almost twice the odds of SAD, while among community members, those with 9/11-related PTSD had 2.5 times the odds of SAD (95% CI: 1.39, 4.39). PTSD was not a significant mediator. Although emerging evidence suggests 9/11 exposure may be associated with SAD, more research is needed, particularly using pooled data sources from other 9/11-exposed cohorts, to fully characterize this relationship.

A Systematic Review of Research on Trauma and Women's Health in the Nurses' Health Study II

OBJECTIVE

To synthesize research on interpersonal trauma and women's health from the Nurses' Health Study II (NHS II) and to analyze conceptualization of interpersonal trauma across studies.

DATA SOURCES

A literature review was conducted in PubMed using a systematic search strategy.

STUDY SELECTION

Articles were included in the review if they used data from the NHS II and involved investigations of interpersonal trauma. Theoretical articles, methodologic articles, and other literature reviews involving the NHS II were excluded. Initially, the search returned 61 articles. After exclusions, 45 articles met the criteria for inclusion in the review and data extraction.

DATA EXTRACTION

Information was extracted and consolidated in an evidence table. Data included study time frame, sample, definition of trauma, outcomes studied, and journal of publication.

DATA SYNTHESIS

Trauma was not operationalized consistently across studies, even though the NHS II assessed trauma experiences in childhood, adolescence, and adulthood. Most investigations focused on childhood abuse, with investigations of childhood sexual abuse overrepresented in comparison to other abuse experiences. Authors conducting studies of trauma at any time in the life course consistently found a negative association with physical and mental health outcomes, which were increased by the presence of posttraumatic stress symptoms. Results from a small number of studies suggested a negative intergenerational impact of trauma on the children of women in the NHS II.

CONCLUSION

Interpersonal trauma across the life course was strongly associated with many leading causes of morbidity and mortality among female nurses. Trauma conceptualization and operationalization varied across studies, and future investigations should leverage the full range of trauma measures available in the NHS II data set.

Lifetime Trauma Exposure and Posttraumatic Stress Disorder Among African Americans and Black Caribbeans by Sex and Ethnicity

OBJECTIVE

Posttraumatic stress disorder (PTSD) is a debilitating disorder requiring timely diagnosis and treatment, with special attention needed for Black populations in the U.S. Yet, stakeholders often fail to recognize Black communities' heterogeneous ethnic composition, thus not allowing diverse sociocultural realities to inform PTSD interventions. This study aims to characterize sex and ethnic differences in lifetime trauma exposure, lifetime PTSD diagnosis and symptoms, and help-seeking among the African Americans and Black Caribbeans in the U.S.

METHOD

This study relied on data from the National Survey of American Life 2001-2003 (NSAL) to investigate the lifetime exposure to traumatic events and prevalence of a clinical PTSD diagnosis based on the DSM-IV among African American (n = 3,570) and Black Caribbean (n = 1,623) adults. 44.5% of respondents were men and 55.5% were women. Logistic regression was utilized to investigate the impact of traumatic events on PTSD.

RESULTS

Several ethnic and sex differences in exposure to potentially traumatic events were identified. African American respondents were more likely to experience spousal abuse and toxin exposure than their Black Caribbean counterparts. Black Caribbeans reported higher lifetime exposure to muggings, natural disasters, harsh parental discipline, being a civilian living in terror and/or being a refugee than African American respondents. Specific to sex, Black men reported more events of combat, a peacekeeper/relief worker, being mugged, toxin exposure, seeing atrocities, and/or injuring someone. Black women were more likely to have been rape/sexual assault and/or intimate partner violence victims. The assaultive violence trauma type was most predictive of lifetime PTSD diagnosis among Black Americans. African American women were more likely to report PTSD symptoms than men, with almost no significant differences in Black Caribbean men and women. Approximately half of Black Americans sought help for their worst traumatic event, commonly engaging family/friends, psychiatrists, and mental health professionals. Further, there were almost no ethnic and sex differences related to professional and non-professional help sought.

CONCLUSION

Future PTSD-related research should aim to characterize the heterogenous experiences of potentially traumatic events within different Black communities. Clinicians working with Black clients should strive to understand the limitations within their tools/interventions in meeting the needs of diverse groups.

Additive Interaction of Work-Related Stress and Sleep Duration on Arthritis Among Middle-Aged Civil Servants

Aim

Occupational strain is recognized as a risk for arthritis, yet little is known about how psychological stress affects arthritis moderated by sleep duration. The objective of this study is to assess work-related stress using the effort-reward imbalance (ERI) model and the job-demand-support (JDS) model on arthritis moderated by sleep duration.

Methods

A nationwide cross-sectional study randomly collected a total of 11,875 middle-aged, employed civil servants from 647 registered governmental institutions. Each participant anonymously and voluntarily filled out a web-based questionnaire and informed consent at the time of the study. Psychosocial work stress was assessed by ERI and JDS measured by a Chinese version of the job content questionnaire.

Results

There were significant odds ratios (ORs) of arthritis positively associated with high ERI (OR = 1.58), high overcommitment (OC) (OR = 1.57), and job demand (OR = 1.31) and negatively associated with job support (OR = 0.69) using multivariate analysis after being adjusted for covariates. For the short sleep duration group, there was an interaction effect of both high ERI and OC on arthritis, with a synergy index of 18.91 and 1.52, respectively. Similarly, there are high ORs of arthritis in both the high job demand and low job support groups.

Conclusion

Work-related stress related to arthritis moderated by sleep duration for civil servants. Civil servants with high job demand and low job support should use caution to reduce the risk of arthritis.

Etiology and Risk Factors for Rheumatoid Arthritis: A State-of-the-Art Review

Rheumatoid arthritis (RA) is the most common systemic inflammatory rheumatic disease. It is associated with significant burden at the patient and societal level. Extensive efforts have been devoted to identifying a potential cause for the development of RA. Epidemiological studies have thoroughly investigated the association of several factors with the risk and course of RA. Although a precise etiology remains elusive, the current understanding is that RA is a multifactorial disease, wherein complex interactions between host and environmental factors determine the overall risk of disease susceptibility, persistence and severity. Risk factors related to the host that have been associated with RA development may be divided into genetic; epigenetic; hormonal, reproductive and neuroendocrine; and comorbid host factors. In turn, environmental risk factors include smoking and other airborne exposures; microbiota and infectious agents; diet; and socioeconomic factors. In the present narrative review, aimed at clinicians and researchers in the field of RA, we provide a state-of-the-art overview of the current knowledge on this topic, focusing on recent progresses that have improved our comprehension of disease risk and development.

Psychiatric and Physical Health Outcomes Associated with Interpersonal Violence: A Propensity Score Matching Approach

This study examined the association between interpersonal violence and a range of psychiatric and physical health outcomes and assessed whether these associations changed when controlling for a stress-related diagnosis. An observational case-control study was conducted on a sample of 4,059 victims of violence. Using propensity score matching a number of risk factors (assessed five years prior assault) were used. Controls were matched 10:1 using the Danish Central Registry System. Outcomes were ICD-10 diagnoses of a range of psychiatric and physical health outcomes in the 15 years post-injury. Statistically significant associations were found for all psychiatric conditions and a diagnosis of a drug or substance misuse disorder. These findings remained even after controlling for a diagnosis of a stress-related disorder. Large scale case-control studies using the Danish nationwide registers enables a powerful way of assessing the relative impact of exposure to interpersonal violence on the development of psychiatric and physical health problems.

The Genetic, Environmental, and Immunopathological Complexity of Autoantibody-Negative Rheumatoid Arthritis

Differences in clinical presentation, response to treatment, and long-term outcomes between autoantibody-positive and -negative rheumatoid arthritis (RA) highlight the need for a better comprehension of the immunopathogenic events underlying the two disease subtypes. Whilst the drivers and perpetuators of autoimmunity in autoantibody-positive RA have started to be disclosed, autoantibody-negative RA remains puzzling, also due its wide phenotypic heterogeneity and its possible misdiagnosis. Genetic susceptibility appears to mostly rely on class I HLA genes and a number of yet unidentified non-HLA loci. On the background of such variable genetic predisposition, multiple exogeneous, endogenous, and stochastic factors, some of which are not shared with autoantibody-positive RA, contribute to the onset of the inflammatory cascade. In a proportion of the patients, the immunopathology of synovitis, at least in the initial stages, appears largely myeloid driven, with abundant production of proinflammatory cytokines and only minor involvement of cells of the adaptive immune system. Better understanding of the complexity of autoantibody-negative RA is still needed in order to open new avenues for targeted intervention and improve clinical outcomes.

Enhancing extracellular vesicles for therapeutic treatment of arthritic joints

Extracellular vesicles are small membrane-derived packages of information that are released from virtually all cell types. These nano-packages contain regulatory material including proteins, lipids, mRNA and microRNA and are a key mechanism of paracellular communication within a given microenvironment. Encompassed with a lipid bilayer, these organelles have been attributed numerous roles in regulating both physiological and pathological functions. Herein, we describe the role of EVs in the context of Rheumatoid and Osteoarthritis and explore how they could be harnessed to treat inflammatory and degenerative joint conditions. These structures offer a promising therapeutic strategy for treating musculoskeletal diseases due to their bioactive content, stability, small size and intrinsic ability to enter the avascular cartilage, a notoriously challenging tissue to target. We also discuss how EVs can be manipulated to load therapeutic cargo or present additional targeting moieties to enhance their beneficial actions and tissue regenerative properties.

The effect of a multidisciplinary lifestyle program for patients with rheumatoid arthritis, an increased risk for rheumatoid arthritis or with metabolic syndrome-associated osteoarthritis: the "Plants for Joints" randomized controlled trial protocol

Low-grade inflammation and metabolic syndrome are seen in many chronic diseases, including rheumatoid arthritis (RA) and osteoarthritis (OA). Lifestyle interventions which combine different non-pharmacological therapies have shown synergizing effects in improving outcomes in patients with other chronic diseases or increased risk thereof, especially cardiovascular disease. For RA and metabolic syndrome-associated OA (MSOA), whole food plant-based diets (WFPDs) have shown promising results. A WFPD, however, had not yet been combined with other lifestyle interventions for RA and OA patients. In this protocol paper, we therefore present Plants for Joints, a multidisciplinary lifestyle program, based on a WFPD, exercise, and stress management. The objective is to study the effect of this program on disease activity in patients with RA (randomized controlled trial [RCT] 1), on a risk score for developing RA in patients with anti-citrullinated protein antibody (ACPA) positive arthralgia (RCT 2) and on pain, stiffness, and function in patients with MSOA (RCT 3), all in comparison with usual care.We designed three 16-week observer-blind RCTs with a waiting-list control group for patients with RA with low to moderate disease activity (2.6 ≤ Disease Activity Score [DAS28] ≤ 5.1, RCT 1, n = 80), for patients at risk for RA, defined by ACPA-positive arthralgia (RCT 2, n = 16) and for patients with metabolic syndrome and OA in the knee and/or hip (RCT 3, n = 80). After personal counseling on diet and exercise, participants join 10 group meetings with 6-12 other patients to receive theoretical and practical training on a WFPD, exercise, and stress management, while medication remains unchanged. The waiting-list control group receives usual care, while entering the program after the RCT. Primary outcomes are: difference in mean change between intervention and control groups within 16 weeks for the DAS28 in RA patients (RCT 1), the RA-risk score for ACPA positive arthralgia patients (RCT 2), and the Western Ontario and McMaster Universities Arthritis Index (WOMAC) score for MSOA patients (RCT 3). Continued adherence to the lifestyle program is measured in a two-year observational extension study.

Women health: Psychological and most prominent somatic problems in 3-year follow-up in Bosnian refugees

BACKGROUND

Little is known about gender differences among people exposed to war related trauma. Aim of this study is to explore gender differences in health status and comorbidity of mental and physical disorders in a cohort of Bosnian refugees followed up for 3 years (1996-1999).

METHODS

This longitudinal study included 534 subjects followed up for 3 years. The interviews were conducted in refugee camps in Varaždin, Croatia in Bosnian language. Data were collected using Harvard Trauma Questionnaire (Bosnian version) and Hopkins Checklist-25, respectively. Physical health disorders were self-reported.

RESULTS

In both assessments there was a statistically significant difference between men and women in the number of physical health disorders, even when results were controlled for educational status. Although there was no difference in total number of symptoms in both assessments (F = 0.32; df = 1; p > 0.05 and F = 1.15; df = 1; p > 0.05), important physical health disorders were significantly more frequent among women than in men in different educational groups, namely high blood pressure and cardiovascular diseases, arthritis, and anaemia. Asthma, tuberculosis, cirrhosis of the liver, ulcer and epilepsy were more frequent in men than in women. There were no differences in frequencies of psychiatric disorders at baseline, but frequency of psychiatric disorders in women was higher at endpoint for uneducated respondents. There was significant difference compared to men in group of respondents without formal education, but only in comorbidity of PTSD and depression which was more often present in females (22.1%) than in males (3.6%).

CONCLUSION

Our findings indicate the importance of gender and education on mental and physical health of people exposed to warrelated trauma. Long term health monitoring and programs, especially related to women's health are needed in order to avoid lasting consequences.

Trauma-informed exercise for women survivors of sexual violence

Compared to their male counterparts, women experience alarmingly high rates of sexual violence (SV). Nearly 20% of women in the USA have been victims of SV, and prevalence of sexual assault among female service members is reported to be even higher, up to 50%. SV results in negative health outcomes like posttraumatic stress disorder, depression, obesity, poor body image, and pain-related disability. Exercise has been shown to positively impact both mental and physical health outcomes in populations experiencing posttraumatic symptoms, yet women survivors of SV are often excluded from exercise trials in trauma-affected populations. The purpose of this paper is to comment on the importance of incorporating women-specific trauma-informed principles in the content and delivery of exercise interventions in trauma-affected populations, particularly as it relates to SV. Researchers discuss the implications of female-specific and trauma-informed exercise considerations for SV survivors. This commentary highlights the need for trauma-informed implementation efforts and outcome measurements in exercise interventions involving women affected by SV. Researchers call for (a) increased qualitative work on trauma-specific implementation efforts across exercise intervention domains and (b) increased assessment of trauma-specific outcomes in exercise trials.

Investigation of C-reactive protein and AIM2 methylation as a marker for PTSD in Australian Vietnam veterans

Chronic inflammation is a key factor in symptomology and comorbidities of post-traumatic stress disorder (PTSD). Levels of a proinflammatory marker, C-reactive protein (CRP) are increased in individuals with PTSD but it is not clear if this is due to trauma exposure or PTSD. Our study aimed to assess the relationship between serum CRP levels, CRP SNPs, methylation, mRNA expression and PTSD in a homogenous trauma exposed Australian Vietnam veteran cohort. We hypothesized that decreased DNA methylation would be associated with increased gene expression and increased peripheral CRP levels in PTSD patients and that this would be independent of trauma. Participants were 299 Vietnam veterans who had all been exposed to trauma and approximately half were diagnosed with PTSD. We observed higher levels of serum CRP in the PTSD group compared to the non-PTSD group but after controlling for BMI and triglycerides the association did not remain significant. No association was found between CRP SNPs and PTSD or CRP levels. Absent in Melanoma 2 (AIM2) which is a mediator of inflammatory response and a determinant of CRP levels was analysed for DNA methylation and mRNA expression. We observed a trend level association between PTSD and AIM2 methylation after controlling for age, smoking, triglycerides, BMI and cell types. There was no significant interaction between PTSD and CRP levels on AIM2 methylation after controlling for covariates. We observed that as AIM2 methylation levels decreased, AIM2 mRNA expression increased. Elevated CRP levels were associated with AIM2 mRNA in the trauma exposed cohort but there was no significant interaction effect with PTSD. Our results could not confirm that CRP is a marker of PTSD independent of trauma in this group of older veterans. CRP may be a broad marker of disease risk, or a marker of PTSD in younger cohorts than those in this study.

Challenges and Opportunities of Targeted Behavioral Interventions for Groups at Risk for Developing Rheumatoid Arthritis

Background: Rheumatoid arthritis (RA) is a serious autoimmune disease which causes painful, swollen joints and can impact quality of life and increase morbidity and mortality. There are several preclinical stages of RA that correspond to at-risk groups that include: genetic risk, risk from behaviors, elevation of RA-related autoantibodies, and early clinical disease manifestations such as undifferentiated arthritis. Early interventions are crucial to slowing progression to and potentially preventing RA onset. Modification of behaviors among at-risk individuals may decrease RA risk. There are several challenges and opportunities in implementing preventative behavioral interventions, which may vary within different at-risk groups. Methods: We performed a narrative review of the literature, including meta-analyses focused on RA risk-related behaviors as well as publications investigating the potential efficacy of behavioral modifications on RA risk. Results: There are multiple behavioral risk factors associated with RA, including smoking, obesity, low physical activity, low quality diet, and poor dental hygiene, which may contribute to progression to clinical RA. Meta-analyses have been performed for smoking, excess body weight, and physical activity. Likelihood of adopting behavioral modifications may increase as RA risk increases. Conclusions: Clinicians may be able to tailor preventative approaches to various RA at-risk groups to help reduce RA risk, but further research is needed. A better understanding of the relationship of behaviors with RA risk and optimized approaches to implementing behavioral changes may allow for clinicians to tailor their preventative approaches for at-risk individuals.

Rheumatoid arthritis and depression

Depression constitutes the most frequent comorbid condition associated with rheumatoid arthritis (RA), with prevalence rates ranging from 14% to 48%. This wide range can be explained by several factors including subtypes of depression considered, instrument of measure (i.e. self-questionnaires versus clinical interview), threshold applied but also the overlap of symptoms between the two conditions. Despite being a frequent comorbid condition in RA, depressive states are repeatedly underdiagnosed and thus, often remain untreated. Consequences are dramatic as conclusive evidence show that depression deleteriously impacts just about all outcomes of RA, including disease activity, arthritis-related complications, level of pain, chance of remission, quality of life and mortality. Importantly, links between depression and RA appear to be bidirectional as if RA patients show increased prevalence of depression. Conversely, patients with depression compared to the general population have higher risk to develop RA. Among the factors explaining this strong association between depression and RA, recent advances have underlined the putative role of models based on the inflammatory hypothesis. Pro-inflammatory cytokines such as tumor necrosis factor, interleukin (IL)-1, IL-6, and IL-18 are involved in RA pathogenesis, but also in depression. Furthermore, the connections between the central nervous system, the peripheral system and the immune system are now better understood. As a consequence of the strong comorbidity and the aggravate prognostic, the management of patient showing this dual diagnosis should be carefully monitor. The common physiopathology also opens the path to utilization of RA treatment in severe depression or treatment-resistant depression.

Posttraumatic Stress Disorder and the Associated Risk of Autoimmune Skin Diseases: A Nationwide Population-Based Cohort Study

OBJECTIVE

Posttraumatic stress disorder (PTSD) is known as a risk factor for various immune-related disorders; however, the association between PTSD and related autoimmune skin diseases (ASDs) remains unclear. This study aimed to investigate the association of PTSD with the risk of related ASDs.

METHODS

Participants were recruited from the National Health Insurance Research Database in Taiwan. We included 9801 patients with PTSD and 39,204 matched controls to assess the risk of developing ASDs. Cox regression model was used for analyses.

RESULTS

After adjusting for confounders, we found an increased risk of ASDs among the patients with PTSD (adjusted hazard ratio [aHR] = 3.00, 95% confidence interval [CI] = 2.21-4.07) compared with that among matched controls. Statistically significant associations were found between PTSD and five individual ASDs, including psoriasis (aHR = 3.81, 95% CI = 1.90-7.67), lichen planus (aHR = 31.63, 95% CI = 4.00-249.91), alopecia areata (aHR = 4.77, 95% CI = 2.47-9.20), autoimmune bullous diseases (aHR = 9.55, 95% CI = 1.98-45.99), and vitiligo (aHR = 16.06, 95% CI = 4.48-57.54).

CONCLUSIONS

Patients with PTSD had an increased risk of developing ASDs compared with the matched controls. Further studies are needed for better understanding of the underlying mechanisms.

Wechselwirkungen zwischen neuroendokrinem System und Immunsystem bei chronisch-entzündlichen Systemerkrankungen

Hormonelle und neuronale Signalwege können die Manifestation einer chronisch-entzündlichen Systemerkrankung entweder begünstigen oder verhindern. Bei bereits manifester Erkrankung modulieren Hormone und Neurotransmitter den Krankheitsverlauf, in dem sie die Krankheitsaktivität erhöhen oder abschwächen. Beispiele hierfür sind der entzündungshemmende Einfluss der körpereigenen und exogenen Glukokortikoide und die entzündungsfördernden Effekte von Stress bei chronisch-entzündlichen Systemerkrankungen. Bei chronisch-entzündlichen Systemerkrankungen ringt das aktivierte Immunsystem mit dem Gehirn und anderen Organsystemen um Energie, was zu vielfältigen Erkrankungsfolgen und Folgeerkrankungen führt: „sickness behaviour“ mit Fatigue-Symptomatik und depressiven Symptomen, Schlafstörungen, Anorexie, Fehl- und Mangelernährung, Knochenabbau, Muskelabbau und kachektische Fettsucht, Insulinresistenz mit Hyperinsulinämie (begleitet von einer Resistenz gegenüber dem Insulin-like growth factor 1), Dyslipidämie, Veränderungen der Steroidhormonachsen, Störungen der Hypothalamus-Hypophysen-Gonaden-Achse, erhöhter Sympathikotonus, herabgesetzte Aktivität des parasympathischen Nervensystems, arterielle Hypertonie und Volumenbelastung, Entzündungsanämie und zirkadiane Rhythmik der Symptomausprägung. Diese für die Patienten gravierenden Folgeerkrankungen, welche den chronisch-entzündlichen Systemerkrankungen inhärent sind, sollten konsequent therapiert werden.

Role of stress in the development of rheumatoid arthritis: a case-control study

OBJECTIVES

The primary objective of this study was to assess the stressful life events preceding the onset of symptoms in RA. The secondary objectives were to assess how early RA patients perceive stress and cope with stressors.

METHODS

A case-control study was performed, comparing patients recently diagnosed with RA to age- and gender-matched control subjects recently hospitalized for an unplanned surgical procedure not known to be influenced by stress. The Social Readjustment Rating Scale assessed the cumulative stress induced by stressful life events in the year preceding the onset of symptoms. Coping strategies, stress and anxiety symptoms were evaluated using validated psychological scales.

RESULTS

Seventy-six subjects were included in each group. The mean Social Readjustment Rating Scale score was twice as high in cases compared with controls [respectively, 167.0 (172.5) vs 83.3 (124.4), P < 0.001]. The association between cumulative stress and RA was statistically significant only in women, with a dose-dependent association between stress and RA. While female patients with RA attributed more often the onset of symptoms to a life event than female controls (70.2 vs 24.5%, P < 0.001), no significant difference was found when comparing male RA patients with male controls (26.9 vs 18.5%, respectively, P = 0.46). Increased perceived stress score (P = 0.04) and coping based on emotions (P = 0.001) were found in cases compared with controls.

CONCLUSION

Patients with early RA reported more life events in the year preceding the onset of symptoms than controls. Gender specificities were found with a significant association between cumulative stress and RA only in women.

Depression and Subsequent Risk for Incident Rheumatoid Arthritis Among Women

OBJECTIVE

To investigate the association of depression with subsequent risk of rheumatoid arthritis (RA) by serologic phenotype.

METHODS

We performed a cohort study using pooled data from the Nurses' Health Study (NHS; 1992-2014) and the NHSII (1993-2015). Depression was defined according to the following composite definition: diagnosis by clinician, regular antidepressant use, or a 5-question Mental Health Inventory score of <60 using time-updated questionnaires during follow-up. Incident RA cases met research criteria by medical record review. Information on covariates, including smoking, diet, and body mass index, was obtained using questionnaires. Cox regression estimated hazard ratios (HRs) and 95% confidence intervals (95% CIs) for RA risk (overall and by serologic phenotype) according to depression status and adjusted for potential confounders. All analyses included a time separation between assessments of depression and the window for RA risk of at least 4 years to lower the possibility that depressive symptoms due to early RA prior to diagnosis explained any associations.

RESULTS

Among 195,358 women, we identified 858 cases of incident RA (65% seropositive) over 3,087,556 person-years (median 17.9 years per participant). Compared to women without depression, those with depression had multivariable HRs as follows: 1.28 (95% CI 1.10-1.48) for all RA; 1.12 (95% CI 0.93-1.35) for seropositive RA; and 1.63 (95% CI 1.27-2.09) for seronegative RA. When analyzing components of the composite depression exposure variable, regular antidepressant use was not associated with subsequent seropositive RA (HR 1.21 [95% CI 0.97-1.49]) and was associated with seronegative RA (HR 1.75 [95% CI 1.32-2.32]).

CONCLUSION

Indicators of depression, specifically antidepressant use, were associated with subsequent increased risk for seronegative RA, and this finding was not explained by measured lifestyle factors prior to clinical presentation.

Posttraumatic stress disorder and changes in diet quality over 20 years among US women

BACKGROUND

Individuals with posttraumatic stress disorder (PTSD) are at increased risk of various chronic diseases. One hypothesized pathway is via changes in diet quality. This study evaluated whether PTSD was associated with deterioration in diet quality over time.

METHODS

Data were from 51 965 women in the Nurses' Health Study II PTSD sub-study followed over 20 years. Diet, assessed at 4-year intervals, was characterized via the Alternative Healthy Eating Index-2010 (AHEI). Based on information from the Brief Trauma Questionnaire and Short Screening Scale for DSM-IV PTSD, trauma/PTSD status was classified as no trauma exposure, prevalent exposure (trauma/PTSD onset before study entry), or new-onset (trauma/PTSD onset during follow-up). We further categorized women with prevalent exposure as having trauma with no PTSD symptoms, trauma with low PTSD symptoms, and trauma with high PTSD symptoms, and created similar categories for women with new-onset exposure, resulting in seven comparison groups. Multivariable linear mixed-effects spline models tested differences in diet quality changes by trauma/PTSD status over follow-up.

RESULTS

Overall, diet quality improved over time regardless of PTSD status. In age-adjusted models, compared to those with no trauma, women with prevalent high PTSD and women with new-onset high PTSD symptoms had 3.3% and 3.6% lower improvement in diet quality, respectively, during follow-up. Associations remained consistent after adjusting for health conditions, sociodemographics, and behavioral characteristics.

CONCLUSIONS

PTSD is associated with less healthy changes in overall diet quality over time. Poor diet quality may be one pathway linking PTSD with a higher risk of chronic disease development.

Traditional and modern management strategies for rheumatoid arthritis

Rheumatoid arthritis (RA) is a serious disorder of the joints affecting 1 or 2% of the population aged between 20 and 50 years worldwide. RA is the foremost cause of disability in developing and Western populations. It is an autoimmune disease-causing inflammation and pain involving synovial joints. Pro-inflammatory markers, including cytokines, such as interleukin -1 (IL-1), IL-6, IL-7, IL-8, and tumor necrosis factor-α (TNF-α) are involved in RA. RA treatment involves TNF-α blockade, B cell therapy, IL-1 and IL-6 blockade, and angiogenesis inhibition. Synthetic drugs available for the treatment of RA include disease-modifying anti-rheumatic drugs (DMARD), such as cyclophosphamide, sulfasalazine, methotrexate, nonsteroidal anti-inflammatory drugs (NSAIDs), and intramuscular gold. These agents induce adverse hepatorenal effects, hypertension, and gastric ulcers. We found that patients diagnosed with chronic pain, as in RA, and those refractory to contemporary management are most likely to seek traditional medicine. Approximately 60-90% of patients with arthritis use traditional medicines. Therefore, the efficacy and safety of these traditional medicines need to be established. The treatment for RA entails a comprehensive multidisciplinary strategy to reduce pain and inflammation and to restore the activity of joints. The potential medicinal plants exhibiting anti-arthritic and anti-rheumatic pharmacological activity are reviewed here.

Perceived Stress and Inflammatory Arthritis: A Prospective Investigation in the Studies of the Etiologies of Rheumatoid Arthritis Cohort

OBJECTIVE

The aim of this study was to determine the association of perceived stress with incident inflammatory arthritis (IA) defined as having at least 1 joint consistent with rheumatoid arthritis (RA)-like synovitis based on examination.

METHODS

We conducted a prospective cohort study in the Studies of the Etiologies of Rheumatoid Arthritis cohort. Participants without IA were recruited if they were a first-degree relative of an RA proband or screened positive for anti-citrullinated protein antibody. Perceived stress was measured using the Perceived Stress Scale-14 (PSS-14), in which scores can range from 0 to 56, and a higher score indicates greater perceived stress. The total PSS-14 score, as well as 2 subscores indicative of perceived distress and self-efficacy, were averaged across all study visits until development of IA or the last follow-up. Hazard ratios (HRs) and 95% confidence intervals (95% CIs) of IA associated with average PSS-14 scores were obtained using Cox proportional hazards models.

RESULTS

The mean total PSS-14 score was 20.4. We found that a 1-point increase in the perceived distress score was significantly associated with a 10-percent increase in the risk of IA (adjusted HR 1.10 [95% CI 1.02-1.19]). Total PSS-14 and self-efficacy were not associated with IA risk (adjusted HR 1.05 [95% CI 0.99-1.10] and 1.04 [95% CI 0.91-1.18], respectively).

CONCLUSION

An association between perceived distress and incident IA was observed in this at-risk cohort. Replication of this finding in other preclinical and at-risk RA populations is needed.

Adverse Childhood Experiences Are Associated with Childhood-Onset Arthritis in a National Sample of US Youth: An Analysis of the 2016 National Survey of Children's Health

OBJECTIVES

To determine whether there is an association between adverse childhood experiences (ACEs) and childhood-onset arthritis, comparing youth with arthritis to both healthy youth and youth with other acquired chronic physical diseases (OCPD); and to examine whether ACEs are associated with disease-related characteristics among children with arthritis.

STUDY DESIGN

In a cross-sectional analysis of data from the 2016 National Survey of Children's Health we examined whether ACEs were associated with having arthritis vs either being healthy or having a nonrheumatologic OCPD. ACE scores were categorized as 0, 1, 2-3, ≥4 ACEs. Multinomial logistic regression models examined associations between ACEs and health status while adjusting for age, sex, race/ethnicity, and poverty status. Among children with arthritis, associations between ACEs and disease-related characteristics were assessed by Pearson χ² analyses.

RESULTS

Compared with children with no ACEs, children with 1, 2-3, and ≥4 ACEs had an increased odds of having arthritis vs being healthy (adjusted OR for ≥4 ACEs, 9.4; 95% CI, 4.0-22.1) and vs OCPD (adjusted OR for ≥4 ACEs, 3.7; 95% CI-1.7, 8.1). Among children with arthritis, ACEs were associated with worse physical impairment.

CONCLUSIONS

Children with higher numbers of ACEs are more likely to have arthritis, when arthritis status is compared either with being healthy or with having OCPD. Further studies are needed to determine the direction of the association between ACEs and childhood arthritis, its impact on disease course, and potential intervention targets that might mitigate these effects.

World Trade Center Health Program: First Decade of Research

The terrorist attacks on 11 September 2001 placed nearly a half million people at increased risk of adverse health. Health effects research began shortly after and continues today, now mostly as a coordinated effort under the federally mandated World Trade Center (WTC) Health Program (WTCHP). Established in 2011, the WTCHP provides medical monitoring and treatment of covered health conditions for responders and survivors and maintains a research program aimed to improve the care and well-being of the affected population. By 2020, funds in excess of USD 127 M had been awarded for health effects research. This review describes research findings and provides an overview of the WTCHP and its future directions. The literature was systematically searched for relevant articles published from 11 September 2001 through 30 June 2020. Synthesis was limited to broad categories of mental health, cancer, respiratory disease, vulnerable populations, and emerging conditions. In total, 944 WTC articles were published, including peer-reviewed articles funded by the WTCHP (n = 291) and other sources. Research has focused on characterizing the burden and etiology of WTC-related health conditions. As the program moves forward, translational research that directly enhances the care of individuals with chronic mental and physical health conditions is needed.

Positive Psychological Factors and Impairment in Rheumatic and Musculoskeletal Disease: Do Psychopathology and Sleep Quality Explain the Linkage?

OBJECTIVE

Little is known about potential mechanisms of action linking protective positive psychological variables and functional disability in patients with rheumatic and musculoskeletal disease. The present study was undertaken to examine symptoms of psychopathology, including stress, depression, anxiety, and sleep quality, as serial mediators of the association between gratitude, self-compassion, self-forgiveness, and functional impairment.

METHODS

We assessed risk and protective factors for functional disability in patients with fibromyalgia (FM), osteoarthritis (OA), rheumatoid arthritis (RA), and ankylosing spondylitis (AS) who were recruited from an Austrian health care facility. Respondents completed online surveys, including the Gratitude Questionnaire 6-item form, the Self-Compassion Scale short form, the Self-Forgiveness and Forgiveness of Others Index, the Perceived Stress Scale 4, the Patient Health Questionnaire 2, the 2-item Generalized Anxiety Disorder Scale, the Sleep Condition Indicator, and the Health Assessment Questionnaire. Bivariate and serial mediation analyses were conducted.

RESULTS

For our sample of 1,218 patients (52% female, n = 632; AS [37%], OA [34%], RA [14%], and FM [24%]), stress, depression, and anxiety, in parallel as first-order mediators, and sleep quality as a second-order mediator, explained the association between positive psychological variables and functional disability.

CONCLUSION

Positive psychological factors exert a beneficial downstream effect on mental well-being, sleep health, and health-related functional impairment. Therapeutic promotion of gratitude, self-compassion, and self-forgiveness may improve mental and physical health in patients with rheumatic and musculoskeletal disease.

Posttraumatic Stress Disorder, Depression, Anxiety, and Persistence of Methotrexate and TNF Inhibitors in Patients with Rheumatoid Arthritis

OBJECTIVE

To examine the relationship of posttraumatic stress disorder (PTSD) with earlier treatment discontinuation and medication adherence in US veterans with rheumatoid arthritis (RA).

METHODS

Veterans Affairs (VA) administrative data (2005-2014) were used to define unique dispensing episodes of methotrexate (MTX) and tumor necrosis factor inhibitors (TNFi) for veterans with RA. Diagnosis codes were used to categorize patients into mutually exclusive groups: PTSD (with/without depression/anxiety), depression/anxiety without PTSD, and neither psychiatric diagnosis. Multivariable Cox proportional hazards models were used to evaluate associations between psychiatric diagnoses and time to disease-modifying antirheumatic drug discontinuation (lapse in refill >90 days). Multivariable logistic regression was used to examine associations of diagnoses with medication nonadherence (proportion of days covered <0.8).

RESULTS

There were 15 081 dispensing episodes of MTX and 8412 dispensing episodes of TNFi. PTSD was independently associated with a greater likelihood of earlier discontinuation of both MTX (hazard ratio [HR] 1.15 [1.10-1.21]) and TNFi (HR 1.20 [1.13-1.28]). Depression/anxiety had a comparable risk of discontinuation for both MTX (HR 1.14 [1.10-1.19]) and TNFi (HR 1.16 [1.10-1.22]). Depression/anxiety, but not PTSD, was associated with higher odds of MTX (odds ratio [OR] 1.12 [1.03-1.22]) and TNFi (OR 1.14 [1.02-1.27]) nonadherence.

CONCLUSION

Veterans with RA and comorbid PTSD, depression, or anxiety had poor persistence of MTX and TNFi therapies. These results suggest that earlier discontinuation and low adherence to therapy among patients with RA with these psychiatric comorbidities may contribute to worse disease outcomes. Mechanisms by which these comorbidities contribute to lower adherence deserve further investigation and may lead to targeted interventions to improve disease outcomes.

Relationships Between Adverse Childhood Experiences and Health Status in Systemic Lupus Erythematosus

OBJECTIVE

Adverse childhood experiences (ACEs) are associated with poor adult health and immune dysregulation. The impact of ACEs on patients with autoimmune disease is unknown. The present study was undertaken to compare the prevalence of ACEs in patients with systemic lupus erythematosus (SLE) to a population-based survey estimate and to investigate relationships between ACEs and SLE outcomes.

METHODS

Data derived from the California Lupus Epidemiology Study (CLUES), a sample of adult patients with SLE. Participants completed a 10-item ACE questionnaire covering 3 domains (abuse, neglect, household challenges). We estimated ACE prevalence in 269 CLUES participants compared to geographically matched respondents from the 2015 California Behavioral Risk Factor Surveillance System (BRFSS), which was standardized to CLUES participant characteristics (age, sex, race/ethnicity). We examined associations of patient-reported and physician-assessed health status measures with overall ACE levels and domains using multivariable linear regression, controlling for sociodemographics, nephritis, and juvenile-onset SLE.

RESULTS

Although specific domains varied, overall ACE levels were similar for CLUES and BRFSS respondents. Among SLE patients, 63.2% had ≥1 ACE, and 19.3% had ≥4. ACEs were more prevalent in those who were older, women, Latino or African American, and without college degrees, but not in those with lupus nephritis. In adjusted models, higher ACE levels and ACE domains were associated with worse patient-reported SLE activity, depression, and health status but were not significantly associated with physician-assessed SLE activity, damage, or severity.

CONCLUSION

Given the association between ACE levels and important patient-reported outcomes in SLE, our study reinforces the need for prevention of ACEs in childhood and for clinical interventions to promote resilience among adults who have experienced ACEs.

Systemic Autoimmune Disease Among Adults Exposed to the September 11, 2001 Terrorist Attack

Objective

Autoimmune disease is an emerging condition among persons exposed to the September 11, 2001 attack on the World Trade Center (WTC). Components of the dust cloud resulting from the collapse of the WTC have been associated with development of a systemic autoimmune disease, as has posttraumatic stress disorder (PTSD). We undertook this study to determine whether dust exposure and PTSD were associated with an increased risk of systemic autoimmune disease in a 9/11‐exposed cohort.

Methods

Among 43,133 WTC Health Registry enrollees, 2,786 self‐reported having a post‐9/11 systemic autoimmune disease. We obtained informed consent to review medical records to validate systemic autoimmune disease diagnoses for 1,041 enrollees. Diagnoses of systemic autoimmune diseases were confirmed by classification criteria, rheumatologist diagnosis, or having been prescribed systemic autoimmune disease medication. Controls were enrollees who denied having an autoimmune disease diagnosis (n = 37,017). We used multivariable log‐binomial regression to examine the association between multiple 9/11 exposures and risk of post‐9/11 systemic autoimmune disease, stratifying by responders (rescue, recovery, and clean‐up workers) and community members (e.g., residents, area workers).

Results

We identified 118 persons with systemic autoimmune disease. Rheumatoid arthritis was most frequent (n = 71), followed by Sjӧgren's syndrome (n = 22), systemic lupus erythematosus (n = 20), myositis (n = 9), mixed connective tissue disease (n = 7), and scleroderma (n = 4). Among 9/11 responders, those with intense dust cloud exposure had almost twice the risk of systemic autoimmune disease (adjusted risk ratio 1.86 [95% confidence interval 1.02–3.40]). Community members with PTSD had a nearly 3‐fold increased risk of systemic autoimmune disease.

Conclusion

Intense dust cloud exposure among responders and PTSD among community members were associated with a statistically significant increased risk of new‐onset systemic autoimmune disease. Clinicians treating 9/11 survivors should be aware of the potential increased risk of systemic autoimmune disease in this population.

Posttraumatic stress disorder and risk of selected autoimmune diseases among US military personnel

BACKGROUND

Increasing evidence suggests a link between posttraumatic stress disorder (PTSD) and physical health. Stress disorders may lead to impairment of the immune system and subsequent autoimmune disease. This study investigated the association between PTSD and risk of selected autoimmune diseases (i.e. rheumatoid arthritis, systemic lupus erythematosus, inflammatory bowel diseases, and multiple sclerosis) among US active duty service members.

METHODS

Using data from the Millennium Cohort Study, incident autoimmune cases between study initiation and September 2015 were identified from medical encounter records in the Military Health System Data Repository (MDR). Participants were classified as having a history of PTSD if they self-reported receiving a health care provider's diagnosis of PTSD or if they screened positive using the PTSD Checklist-Civilian Version. Hazard ratios (HRs) and 95% confidence intervals (CIs) were estimated using multivariable Cox regression models adjusted for demographics and history of another mental health condition.

RESULTS

Among 120,572 participants followed for a mean of 5.2 years, risk of any of the selected autoimmune diseases was 58% higher for those with a history of PTSD (HR = 1.58, 95% CI: 1.25, 2.01) compared with no history of PTSD. Further adjustment for BMI, smoking status, and alcohol use had little impact on the effect estimates, and results were not appreciably different according to combat experience and history of physical or sexual trauma.

CONCLUSIONS

Active duty military personnel with PTSD may have an elevated risk of a range of autoimmune diseases, regardless of combat experience or prior trauma. Future research is needed to understand potential mechanisms which may inform future mitigative strategies in reducing extra-neuropsychiatric health problems among those with PTSD.

International meta-analysis of PTSD genome-wide association studies identifies sex- and ancestry-specific genetic risk loci

The risk of posttraumatic stress disorder (PTSD) following trauma is heritable, but robust common variants have yet to be identified. In a multi-ethnic cohort including over 30,000 PTSD cases and 170,000 controls we conduct a genome-wide association study of PTSD. We demonstrate SNP-based heritability estimates of 5-20%, varying by sex. Three genome-wide significant loci are identified, 2 in European and 1 in African-ancestry analyses. Analyses stratified by sex implicate 3 additional loci in men. Along with other novel genes and non-coding RNAs, a Parkinson's disease gene involved in dopamine regulation, PARK2, is associated with PTSD. Finally, we demonstrate that polygenic risk for PTSD is significantly predictive of re-experiencing symptoms in the Million Veteran Program dataset, although specific loci did not replicate. These results demonstrate the role of genetic variation in the biology of risk for PTSD and highlight the necessity of conducting sex-stratified analyses and expanding GWAS beyond European ancestry populations.

Autonomic and Redox Imbalance Correlates With T-Lymphocyte Inflammation in a Model of Chronic Social Defeat Stress

Patients diagnosed with post-traumatic stress disorder (PTSD) are at a significantly elevated risk of developing comorbid inflammatory conditions, but the mechanisms underlying this predilection remain unclear. Our previous work has shown that T-lymphocytes exposed to elevated levels of norepinephrine (NE) displayed a pro-inflammatory signature reminiscent of an autoreactive phenotype. With this, we hypothesized that the increased sympathetic tone observed during psychological trauma may be promoting pro-inflammatory T-lymphocytes, which causes a predisposition to comorbid inflammatory conditions. Here, we examined the consequences of psychological trauma on splenic T-lymphocytes using a mouse model of repeated social defeat stress. Social defeat led to anxiety-like and depression-like behavior as has been previously described. The spleens of socially-defeated mice showed significant elevations of NE, tyrosine hydroxylase (TH), and acetylcholinesterase (ACHE) levels, which appeared to be due in part to increased expression within T-lymphocytes. Additionally, T-lymphocytes from stressed animals showed higher levels of pro-inflammatory cytokines and mitochondrial superoxide. Interestingly, in this model system, close associations exist within splenic T-lymphocytes amid the autonomic, inflammatory, and redox environments, but these only weakly correlate with individual behavioral differences among animals suggesting the psychological and physiological manifestations of trauma may not be tightly coupled. Last, we describe, for the first time, elevations in calprotectin levels within T-lymphocytes and in circulation of psychologically stressed animals. Calprotectin correlated with both behavioral and physiological changes after social defeat, suggesting the potential for a new biological marker and/or therapeutic target for psychological trauma and its inflammatory comorbidities.

Depression and the risk of rheumatoid arthritis

PURPOSE OF REVIEW

Rheumatoid arthritis (RA) is associated with negative changes in mental health. This is generally attributed to symptoms of inflammation and the adverse impact of RA on quality of life and functioning. Until recently, causal pathways in the opposite direction have not been fully appreciated. This review examines the recent literature on the risk of RA associated with depression.

RECENT FINDINGS

Current literature links depression with an increased risk of RA and with a more detrimental disease course. These effects are likely to be partially mediated by negative effects of depression on coping with RA and on factors such as medication adherence, both of which lead to poorer disease outcomes. Growing evidence also suggests that inflammation is central both to depression and RA and may account for some of the complex interplay between these conditions.

SUMMARY

Awareness of a bidirectional relationship between depression and RA through a biopsychosocial framework may assist clinicians in maintaining an appropriate index of suspicion about the co-occurrence of these conditions. This review also suggests an important need for integration of rheumatologic and mental health services and generates hypotheses for future research towards a better understanding of both depression and RA.

Posttraumatic stress disorder symptoms and television viewing patterns in the Nurses' Health Study II: A longitudinal analysis

Introduction

The relation between TV viewing and posttraumatic stress disorder (PTSD) is controversial; prior work focused exclusively on whether TV viewing of disaster events constitutes a traumatic stressor that causes PTSD. This study evaluates a possible bidirectional relation between PTSD and TV viewing in community-dwelling women.

Methods

Data are from the PTSD subsample of the Nurses’ Health II study, an ongoing prospective study of women aged 24–42 years at enrollment and who have been followed biennially (N = 50,020). Trauma exposure and PTSD symptoms (including date of onset) were assessed via the Brief Trauma Questionnaire and the Short Screening Scale for DSM-IV PTSD. Average TV viewing was reported at 5 times over 18 years of follow-up. Linear mixed models assessed differences in TV viewing patterns by trauma/PTSD status. Among women with trauma/PTSD onset during follow-up (N = 14,374), linear spline mixed models assessed differences in TV viewing patterns before and after PTSD onset.

Results

Women with high PTSD symptoms reported more TV viewing (hours/wk) compared to trauma-unexposed women at all follow-up assessments (β = 0.14, SE = 0.01, p < .001). Among the women who experienced trauma during follow-up, significant increases in TV viewing (hours/day) prior to onset of high PTSD symptom levels were evident (β = 0.15, SE = 0.02, p < .001).

Conclusions

TV viewing following trauma exposure may be a marker of vulnerability for developing PTSD and also a consequence of having PTSD. High TV viewing levels may be linked with ineffective coping strategies or social isolation, which increase risk of developing PTSD.

Pain and affective distress in arthritis: relationship to immunity and inflammation

INTRODUCTION

Most arthritides are associated with pain and psychological distress (clinically significant depression and anxiety). Pain and depression are mutually exacerbating; both may continue even when joint involvement appears well controlled. Area covered: There is strong evidence that arthritis-related stress impacts the central nervous system and, together with peripheral inflammatory changes, can cause central sensitization that can lead to chronic pain and worsening of affective distress. Cytokines and chemokines participate both in joint inflammation and in central sensitization. We review evidence of these relationships in five arthritides, namely rheumatoid arthritis, ankylosing spondylitis, psoriatic arthritis, gout, and in osteoarthritis of the hips and knees. Central sensitization in these conditions results in long-lasting pain and psychological distress. Expert commentary: Chronic pain and depression are important but often neglected in the clinical assessment and treatment of arthritis. The potential role of biologic cytokines and Janus kinase inhibitors in dealing with these symptoms needs further study.

Post-traumatic stress disorder and serum cytokine and chemokine concentrations in patients with rheumatoid arthritis✰

OBJECTIVE

Although post-traumatic stress disorder (PTSD) is identified as a risk factor in the development of rheumatoid arthritis (RA), associations of PTSD with disease progression are less clear. To explore whether PTSD might influence disease-related measures of systemic inflammation in RA, we compared serum cytokine/chemokine (cytokine) concentrations in RA patients with and without PTSD.

METHODS

Participants were U.S. Veterans with RA and were categorized as having PTSD, other forms of depression/anxiety, or neither based on administrative diagnostic codes. Multiplex cytokines were measured using banked serum. Associations of PTSD with cytokine parameters (including a weighted cytokine score) were assessed using multivariable regression, stratified by anti-CCP status and adjusted for age, sex, race, and smoking status.

RESULTS

Among 1,460 RA subjects with mean (SD) age of 64 (11) years and disease duration of 11 (11) years, 91% were male, 77% anti-CCP positive, and 80% ever smokers. Of these, 11.6% had PTSD, 23.7% other depression/anxiety, and 64.7% had neither. PTSD, but not depression/anxiety, was associated with a higher cytokine score and number of high-concentration analytes in adjusted models, though this was limited to anti-CCP positive subjects. PTSD was associated with heightened expression of several individual cytokines including IL-1β, IL-2, IL-4, IL-5, IL-6, IL-7, IL-10, IL-12, IL-17, IFN-γ, GM-CSF, MCP-1, and TNF-α.

CONCLUSION

Anti-CCP positive RA patients with PTSD have higher serum cytokine concentrations than those without PTSD, demonstrating that systemic inflammation characteristic of RA is heightened in the context of this relatively common psychiatric comorbidity.