The association of unipolar depression with thirty-day mortality after hospitalization for infection: A population-based cohort study in Denmark

Exploring the causal effects of depression and antidepressants on COVID-19

BACKGROUND

While existing studies have suggested an increased risk of COVID-19 in patients with depression, the causal impact of MDD on the severity of COVID-19 remains to be validated. Additionally, the potential impact of antidepressant medication on the risk of COVID-19 is not known.

METHODS

In our study, we applied a Mendelian Randomization (MR) method, leveraging summary data from GWAS, to evaluate the potential causal effects of depression on three COVID-19 outcomes. Furthermore, we investigated the causal effects of antidepressants on COVID-19 outcomes. The COVID-19 datasets contain information on various stages of the disease, including SARS-CoV-2 infection (N = 2,597,856), hospitalized COVID-19 (N = 2,095,324), and critical COVID-19 (N = 1,086,211). Datasets for depression and antidepressants were comprised of 1,349,887 and 106,785 participants, respectively.

RESULTS

Employing the inverse variance-weighted (IVW) method, we show a causal association between depression and three COVID-19 outcomes. Specifically, we found that genetic liability to depression is linked to critical COVID-19 (OR: 1.28, 95 % CI: 1.13-1.46), hospitalized COVID-19 (OR: 1.23, 95 % CI: 1.13-1.34), and SARS-CoV-2 infection (OR: 1.06, 95 % CI: 1.02-1.10). Interestingly, the use of antidepressants was not associated with COVID-19, with the odds ratios for critical COVID-19 (OR: 1.05, 95 % CI: 0.88-1.26), hospitalization (OR: 1.01, 95 % CI: 0.90-1.13), and SARS-CoV-2 infection (OR: 1.03, 95 % CI: 0.99-1.08) indicating no causal impact.

CONCLUSION

Our study indicates that genetic liability to depression may increase the susceptibility to COVID-19 and its severe forms. The lack of causal effect of antidepressant use on COVID-19 implies antidepressant medication may counteract the detrimental effect of depression on COVID-19.

Identifying depression's genetic role as a precursor to sepsis and increased mortality risk: Comprehensive insights from mendelian randomization analysis

BACKGROUND

Previous retrospective studies have shown a correlation between depression and increased risk of infections, including a moderate rise in sepsis likelihood associated with severe depression and anxiety. To investigate the potential causal links between depression, sepsis, and mortality risks, while considering confounding factors, we employed a Mendelian randomization (MR) approach.

METHODS

In this two-sample Mendelian randomization study, we analyzed data from a large-scale genome-wide association study on depression, involving 807,553 European individuals (246,363 cases, 561,190 controls). We extracted SNP associations with sepsis and 28-day mortality from UK Biobank GWAS outcomes. The correlation analysis primarily employed the inverse-variance weighted method, supplemented by sensitivity analyses for heterogeneity and pleiotropy assessment.

RESULTS

Our analysis revealed a potential causal link between depression and an increased risk of sepsis (OR = 1.246, 95% CI: 1.076-1.442, P = 0.003), but no causal association was found with sepsis-induced mortality risk (OR = 1.274, 95% CI: 0.891-1.823, P = 0.184). Sensitivity analyses confirmed the robustness of these findings.

CONCLUSIONS

We identified a potential causal association between depression and heightened sepsis risk, while no link was found with sepsis-induced mortality. These findings suggest that effective management of depression could be important in preventing sepsis.

Severe mental illness and mortality in sepsis and septic shock: a systematic review and meta-analysis

BACKGROUND

There have been conflicting reports regarding the case-fatality outcomes associated with sepsis and septic shock in patients with severe mental illness (SMI).

METHODS

We searched Medline®, Web of Science® and the Cochrane Library® databases (from inception to 4-July-2023) for papers reporting outcomes associated with sepsis and septic shock in adult with (cases) vs. without SMI (controls). The main study outcome was the unadjusted case-fatality rate at hospital discharge, or 30 days if unavailable. Secondary outcomes included the rates of adjusted case-fatality at hospital discharge.

RESULTS

A total of six studies were included in the systematic review, of which four provided data for meta-analysis involving 2,124,072 patients. Compared to controls, patients with SMI were younger and more frequently women. Unadjusted analyses showed that SMI patients had a lower case-fatality rate associated with sepsis and septic shock than their non-SMI counterparts (OR 0.61, 95% CI [0.58-0.65], PI 95% CI [0.49-0.77], I2 = 91%). Meta-regression and subgroup analyses showed that the denominator of the study population (i.e. septic shock or sepsis) was associated with the outcome with an R2 of 59.7%.

CONCLUSION

In conclusion, our study reveals a survival advantage of SMI patients over their non-SMI counterparts. Further research is needed to fully elucidate the mechanisms involved and to develop targeted interventions that can improve the prognosis of both SMI and non-SMI patients facing sepsis.

Causal associations between severe mental illness and sepsis: a Mendelian randomization study

Objective

SMI (severe mental illness) has been identified as a risk factor for sepsis in observational studies; however, the causal association between them has yet to be firmly established. We conducted MR (mendelian randomization) to unveil the causal relationship between SMI and sepsis as well as sepsis mortality.

Methods

GWAS (Genome-wide association) data for major depression and schizophrenia were selected as exposure. GWAS data for sepsis and sepsis mortality were selected as outcome. Genetic variants significantly associated with the exposure (P value<1x10-6) were selected as instruments. We primarily employed the IVW (inverse-variance weighted) method for analysis. Furthermore, we employed Cochrane's Q test to assess heterogeneity and the MR-Egger intercept test to identify horizontal pleiotropy.

Results

We selected 108 SNPs (single nucleotide polymorphism) used to predict major depression and 260 SNPs that predicted schizophrenia. Genetically predicted major depression was suggestively linked to a higher sepsis risk (OR=1.13, 95%CI 1.02-1.26, P=0.023). In contrast, MR analysis did not find an association between schizophrenia and sepsis risk (OR=1.00, 95%CI 0.97-1.04, P=0.811). Furthermore, no significant causal evidence was found for genetically predicted SMI in sepsis mortality. Moreover, no heterogeneity and horizontal pleiotropy were detected.

Conclusion

Our research revealed a suggestive association between genetically predicted major depression and an elevated risk of sepsis in individuals of European ancestry. This finding can serve as a reminder for clinicians to consider the possibility of subsequent infection and sepsis in depressive patients, which may help reduce the incidence of sepsis in individuals with depression.

Septic Shock Short-Term Outcomes in Patients With Psychiatric Disorders: Analysis From the National Inpatient Sample Database

BACKGROUND

Major psychiatric disorders are associated with lower life expectancy primarily due to comorbid illnesses and suboptimal access to health care. Large-scale contemporary data in the United States on in-hospital mortality of patients with major psychiatric disorder and sepsis are lacking.

OBJECTIVE

To describe the short-term outcomes of hospitalized patients with major psychiatric disorders and septic shock.

METHODS

We performed a retrospective cohort study using the National Inpatient Sample database from 2016 to 2019 to identify septic shock hospitalizations in patients with versus without major psychiatric disorder (defined as schizophrenia and affective disorders). Baseline variables and in-hospital mortality trends were compared between the 2 groups.

RESULTS

Out of 1,653,255 hospitalizations with septic shock identified between 2016 and 2019, 16.2% had a diagnosis of major psychiatric disorder as defined above. After adjusting for various patient-level and hospital-level demographics and coexisting clinical conditions in a multivariable logistic regression, the odds of in-hospital mortality in patients with any major psychiatric disorder were 0.71 times that of those without a diagnosis of psychiatric illness (95% confidence interval [CI], 0.69-0.73; P < 0.001). Similarly, when the disorders were divided into 2 categories for subanalysis, those with schizophrenia had 38% lower odds of dying compared to those without schizophrenia (adjusted odds ratio, 0.62; 95% CI, 0.58-0.66; P < 0.001). Those with affective disorders had 25% lower odds of in-hospital mortality than those without a diagnosis of an affective disorder (adjusted odds ratio, 0.75; 95% CI, 0.73-0.77; P < 0.001). The adjusted mean length of stay for those diagnosed with major psychiatric disorder was 0.38 days longer than those without significant psychiatric illness (95% CI, 0.28-0.49; P < 0.001). On the other hand, the mean hospitalization charges were $10,516 less for patients with a major psychiatric disorder compared to those without (95% CI, -$11,830 to -$9,201; P < 0.001).

CONCLUSIONS

Hospitalized patients with major psychiatric disorder and septic shock had lower risk of short-term mortality. Further studies are needed to examine the reasons behind this lower in-hospital mortality risk.

Association of severe mental illness and septic shock case fatality rate in patients admitted to the intensive care unit: A national population-based cohort study

BACKGROUND

Patients with severe mental illness (SMI) (i.e., schizophrenia, bipolar disorder, or major depressive disorder) have been reported to have excess mortality rates from infection compared to patients without SMI, but whether SMI is associated with higher or lower case fatality rates (CFRs) among infected patients remains unclear. The primary objective was to compare the 90-day CFR in septic shock patients with and without SMI admitted to the intensive care unit (ICU), after adjusting for social disadvantage and physical health comorbidity.

METHODS AND FINDINGS

We conducted a nationwide, population-based cohort study of all adult patients with septic shock admitted to the ICU in France between January 1, 2014, and December 31, 2018, using the French national hospital database. We matched (within hospitals) in a ratio of 1:up to 4 patients with and without SMI (matched-controls) for age (5 years range), sex, degree of social deprivation, and year of hospitalization. Cox regression models were conducted with adjustment for smoking, alcohol and other substance addiction, overweight or obesity, Charlson comorbidity index, presence of trauma, surgical intervention, Simplified Acute Physiology Score II score, organ failures, source of hospital admission (home, transfer from other hospital ward), and the length of time between hospital admission and ICU admission. The primary outcome was 90-day CFR. Secondary outcomes were 30- and 365-day CFRs, and clinical profiles of patients. A total of 187,587 adult patients with septic shock admitted to the ICU were identified, including 3,812 with schizophrenia, 2,258 with bipolar disorder, and 5,246 with major depressive disorder. Compared to matched controls, the 90-day CFR was significantly lower in patients with schizophrenia (1,052/3,269 = 32.2% versus 5,000/10,894 = 45.5%; adjusted hazard ratio (aHR) = 0.70, 95% confidence interval (CI) 0.65,0.75, p < 0.001), bipolar disorder (632/1,923 = 32.9% versus 2,854/6,303 = 45.3%; aHR = 0.70, 95% CI = 0.63,0.76, p < 0.001), and major depressive disorder (1,834/4,432 = 41.4% versus 6,798/14,452 = 47.1%; aHR = 0.85, 95% CI = 0.81,0.90, p < 0.001). Study limitations include inability to capture deaths occurring outside hospital, lack of data on processes of care, and problems associated with missing data and miscoding in medico-administrative databases.

CONCLUSIONS

Our findings suggest that, after adjusting for social disadvantage and physical health comorbidity, there are improved septic shock outcome in patients with SMI compared to patients without. This finding may be the result of different immunological profiles and exposures to psychotropic medications, which should be further explored.

Major depressive disorders increase the susceptibility to self-reported infections in two German cohort studies

INTRODUCTION

In several claims-based studies, major depressive disorder (MDD) has been associated with increased risk of hospitalization due to acute infections. It remains unclear if this is a causal effect, and if it generalizes to an increased susceptibility to infections.

METHODS

We used data of the BiDirect (n = 925) and the HaBIDS (n = 1007) cohort studies to estimate the effect of MDD on self-reported infections, which were assessed with identical infection susceptibility questionnaires in both studies. We used the Center for Epidemiologic Studies Depression Scale (CES-D) to examine if there was a dose-response relationship between depressive symptom severity and self-reported infections.

RESULTS

BiDirect participants with MDD diagnosis (48%) had a higher risk of lower respiratory tract infections (incidence rate ratio 1.32, 95% confidence interval [1.00-1.75]), gastrointestinal infections (1.68 [1.30-2.16]) and fever (1.48 [1.11-1.98]) after adjusting for confounders identified by a directed acyclic graph approach. There was a dose-response relationship, i.e. individuals with higher CES-D scores reported more infections. Effect sizes were similar in HaBIDS (4% individuals with MDD).

CONCLUSION

We found increased risks of mild infections in patients with MDD diagnosis and a dose-response relationship between depressive symptom severity and infection frequency. While causal immunological pathways remain unclear, the results of our study might contribute to a change in prevention strategies, e.g. by recommending vaccination against influenza and S. pneumoniae to MDD patients because observed effect sizes in our study are similar to those of patients with cardiovascular and metabolic diseases for which the respective vaccinations are recommended.

Prospective associations between depression and risk of hospitalisation for infection: Findings from the UK Biobank

BACKGROUND

Associations between depression and non-communicable disease have been well-described. However, the evidence for its role in the development of infectious disease is less understood. We aimed to examine prospective associations between depression and risk of hospitalisation for infection in middle-aged adults from the UK Biobank (linked with Hospital Episode Statistics) and assessed the role of several depression-related factors.

METHODS

We assessed prospective associations between depression status at the baseline assessment (2006-2010) and hospitalisations for infection up to the end of March 2016 in 460,418 middle-aged adults enrolled in the UK Biobank (mean age = 56.23 ± 8.11 years, 53.5% female). Cox regression was used to assess associations between depression and subsequent hospitalisations for any infections, as well as infection subtypes, viral infections, and bacterial infections. Amongst those with depression, we also examined the role of depression duration, the age of onset, and the use of antidepressants in hospitalisation risk.

RESULTS

Depression at baseline was prospectively associated with an increased risk of hospitalisation for infection (adjusted hazard ration (aHR) = 1.20, 95% confidence interval (CI) = 1.16 to 1.25). This association was found for all infection subtypes apart from infections of the central nervous system (p = 0.911) and the skin (p = 0.313). Receipt of a depression diagnosis in late adulthood and use of antidepressants (but only in those with none/mild depressive symptoms at baseline) increased the risk of hospitalisation for infection amongst those with depression.

CONCLUSIONS

These findings suggest that depression might be a risk factor which could be used to identify those at risk of hospitalisation for infection. Future research is required to understand the underlying factors that might result in this increased risk, so that targeted interventions can be developed.

FUNDING

AD and AR are funded by Guy's Charity grant number EIC180702 (MLTC Challenge Fund); AD and JAT are co-funded by MRC and NIHR through grant number MR/S028188/1. IB is supported by the NIHR Maudsley BRC and by the NIHR Collaboration for Leadership in Applied Health Research and Care South Londnoo at King's College Hospital NHS Foundation Trust, King's College London. The views expressed are those of the author[s] and not necessarily those of the ESRC, NIHR, the Department of Health and Social Care or King's College London.

Predictors for mortality in patients admitted with suspected bacterial infections - A prospective long-term follow-up study

OBJECTIVE

The aim was to examine predictors for all-cause mortality in a long-term follow-up study of adult patients with infectious diseases of suspected bacterial origin.

METHODS

A prospective observational study of patients admitted to the emergency department during 1.10.2017-31.03.2018. We used Cox regression to estimate adjusted hazard ratios (aHR) with 95% confidence intervals for mortality.

RESULTS

A total of 2110 patients were included (median age 73 years). After a median follow-up of 2.1 years 758 (35.9%, 95% CI 33.9-38.0%) patients had died. Age (aHR1.05; 1.04-1.05), male gender (aHR 1.21; 1.17-1.25), cancer (aHR 1.80; 1.73-1.87), misuse of alcohol (aHR 1.30; 1.22-1.38), if admitted with sepsis within the last year before index admission (aHR 1.56;1.50-1.61), a Sequential Organ Failure Assessment (SOFA) score ≥2 (aHR 1.90; 1.83-1.98), SIRS criteria ≥2 (aHR 1.23;1.18-1.28) at admission to the ED, length of stay (aHR 1.05; 1.04-1.05) and devices and implants as sources of infection (aHR 7.0; 5.61-8.73) were independently associated with mortality. Skin infections and increasing haemoblobin values reduced the risk of death.

CONCLUSIONS

More than one-third of a population of patients admitted to the emergency department with infectious diseases of suspected bacterial origin had died during a median follow up of 2.1 years. The study identified several independent predictors for mortality.

Impact of history of mental disorders on short-term mortality among hospitalized patients with sepsis: A population-based cohort study

Background

Mental disorders are associated with markedly reduced life expectancy, in part due to an increased risk of death due to infection, likely reflecting sepsis-associated mortality. Patients with mental disorders are at an increased risk of sepsis, but data on the prognostic impact of mental disorders in sepsis are sparse, showing conflicting findings.

Methods

We used statewide data to identify hospitalizations aged ≥18 years with sepsis in Texas during 2014–2017. Mental disorders, including mood, anxiety, psychosis, and personality disorders were identified using Clinical Classification Software codes. Multilevel, multivariable logistic regression with propensity adjustment (primary model), with propensity score matching, and multivariable logistic regression as alternative models, were used to estimate the association between mental disorders and short-term mortality (defined as in-hospital mortality or discharge to hospice). Additional models were fitted for sensitivity analyses and to estimate the prognostic associations of individual categories of mental disorders.

Results

Among 283,025 hospitalizations with sepsis, 56,904 (20.1%) had mental disorders. Hospitalizations with vs without mental disorders were younger (age 18–44 years 12.2% vs 10.6%), more commonly white (61.0% vs 49.8%), with lower burden of comorbidities (mean [SD] Deyo comorbidity index 2.53 [2.27] vs 2.73 [2.47]), and with lower need for organ support (mechanical ventilation 32.8% vs 36.0%); p<0.0001 for all comparisons. Crude short-term mortality among sepsis hospitalizations with and without mental disorders was 25.0% vs 32.8%, respectively. On adjusted analyses, mental disorders remained associated with lower odds of short-term mortality (adjusted odds ratio 0.792 [95% CI 0.772–0.812]). This finding was consistent on the alternative modeling approaches, sensitivity analyses, and examination of individual categories of mental disorders.

Conclusions

Mental disorders were associated, unexpectedly, with markedly lower risk of short-term mortality in sepsis. Further studies to examine the mechanisms underlying these findings may inform future efforts to improve sepsis outcomes.

The Association between ADHD and the Severity of COVID-19 Infection

OBJECTIVE

Patients with ADHD are at increased risk of acquiring COVID-19. The present study assessed the possibility that ADHD also increases the risk of severe COVID-19 infection.

METHOD

We assessed 1,870 COVID-19 positive patients, aged 5 to 60 years, registered in the database of Leumit Health Services (LHS, Israel), February to -June 2020, of whom 231 with ADHD. Logistic regression analysis models evaluated the association between ADHD and the dependent variables of being symptomatic/referral to hospitalization, controlling for demographic and medical variables.

RESULTS

Age, male sex, and BMI were confirmed to be significant risk factors for increased COVID-19 severity. ADHD was found to be associated with increased severity of COVID-19 symptoms (OR = 1.81, 95% CI [1.29, 2.52], p < .05) and referral to hospitalization (OR =1.93, 95% CI [1.06, 3.51], p = .03).

CONCLUSION

ADHD is associated with poorer outcomes in COVID-19 infection.

Keep Your Friends Close, but Your Enemies Closer: Role of Acid Sphingomyelinase During Infection and Host Response

Breakdown of the inert and constitutive membrane building block sphingomyelin to the highly active lipid mediator ceramide by extracellularly active acid sphingomyelinase is tightly regulated during stress response and opens the gate for invading pathogens, triggering the immune response, development of remote organ failure, and tissue repair following severe infection. How do one enzyme and one mediator manage all of these affairs? Under physiological conditions, the enzyme is located in the lysosomes and takes part in the noiseless metabolism of sphingolipids, but following stress the protein is secreted into circulation. When secreted, acid sphingomyelinase (ASM) is able to hydrolyze sphingomyelin present at the outer leaflet of membranes to ceramide. Its generation troubles the biophysical context of cellular membranes resulting in functional assembly and reorganization of proteins and receptors, also embedded in highly conserved response mechanisms. As a consequence of cellular signaling, not only induction of cell death but also proliferation, differentiation, and fibrogenesis are affected. Here, we discuss the current state of the art on both the impact and function of the enzyme during host response and damage control. Also, the potential role of lysosomotropic agents as functional inhibitors of this upstream alarming cascade is highlighted.

Teorias evolucionistas da depressão: panorama e perspectivas

Resumo A depressão tem alcançado níveis epidêmicos ao redor do mundo. Seria a depressão um distúrbio mental, como é consenso na saúde mental? Teóricos evolucionistas têm-se questionado quanto à função da depressão e proposto modelos específicos para explicá-la. O objetivo deste artigo é apresentar teorias evolucionistas da depressão, discutir as relações de complementariedade e contraposição entre elas e as implicações sociais e práticas para o tratamento da depressão. Essas reflexões e questionamentos no domínio da saúde mental podem influenciar novos estudos a partir de uma perspectiva não patológica da depressão. No âmbito da psicologia essa perspectiva fornece subsídios para repensar a psicoterapia com o deprimido, enfocando a análise causal e a resolução de problemas. Sugere-se a realização de estudos empíricos com a finalidade de testar e sistematizar as teorias evolucionistas da depressão.

Association of a Prior Psychiatric Diagnosis With Mortality Among Hospitalized Patients With Coronavirus Disease 2019 (COVID-19) Infection

This cohort study evaluates the association between prior psychiatric diagnosis and mortality among patients hospitalized with coronavirus disease 2019 (COVID-19).

Depression is associated with subsequent risk of pleural empyema

Background:

Respiratory system infections are prevalent in patients with depression. However, it remains unclear if patients with depression are at an increased risk of developing pleural empyema.

Methods:

We conducted a retrospective cohort study using data from the National Health Insurance Research Database of Taiwan. The depression group included 42,283 newly diagnosed patients between 2000 and 2012. The comparison group included the same number of individuals without depression, frequency matched for age, sex, comorbidities, and the year of diagnosis. The occurrence of pleural empyema was monitored until the end of 2013.

Results:

The overall incidence of pleural empyema was 1.32-fold higher in the depression group than in the comparison group (3.94 versus 2.97 per 10,000 person-years), with an adjusted hazard ratio of 1.33 (95% confidence interval, 1.27−1.40). Stratified analyses by age, sex, and comorbidity revealed that the crude and adjusted hazard ratios of pleural empyema associated with depression were significant in all subgroups. The 30-day mortality for pleural empyema was higher, but not significantly, in the depression group compared to the comparison group (10.7% versus 6.4%, adjusted odds ratio = 2.23, 95% confidence interval, 0.77−6.49).

Conclusion:

An association between depression and the development of pleural empyema may exist; however, more evidence is required to support this association.

The reviews of this paper are available via the supplemental material section.

Psychiatric Morbidity After Critical Illness

Critical illness survivors frequently have substantial psychiatric morbidity, including posttraumatic stress, depression, and anxiety symptoms. Prior psychiatric illness is a potent predictor of postcritical illness psychiatric morbidity. Early emotional distress and memories of frightening psychotic and nightmarish intensive care unit (ICU) experiences are risk factors for longer term psychiatric morbidity. ICU diaries may be effective in decreasing psychiatric morbidity after critical illness, though these and other interventions deserve further study.