Association between C reactive protein and depression in a population of healthy adults: the Cooper Center Longitudinal Study

Inflammation as an aetiological trigger for depressive symptoms in a prospective cohort of patients with inflammatory bowel disease

OBJECTIVE

Inflammatory bowel disease (IBD) is often comorbid with mood disorders and depressive symptoms. The aetiology of depressive symptoms in IBD, however, remains largely unknown. Consistent with the inflammatory hypothesis of depression, the aim of this study was to explore the prospective associations between inflammatory biomarkers and depressive symptoms in a cohort of IBD patients with and without a previous clinical diagnosis of mood disorder.

METHOD

IBD clinical activity was determined using the Harvey-Bradshaw Index for CD and the Partial Mayo score for UC; serum C-reactive protein (CRP) and faecal calprotectin (fCAL) were used as biomarkers of systemic and intestinal inflammation, respectively. Participants were administered the Hospital Anxiety and Depression Scale-depression (HADS-D) at baseline and 1-year follow-up.

RESULTS

Eighty-four participants (50 ± 16 years; 75% UC and 25% CD) were included in the main analyses. Longitudinal moderated regression models showed that baseline CRP significantly predicted follow-up HADS-D scores among individuals with a previous mood disorder diagnosis (β = 0.843, p < .001), but not among individuals without (β = -0.013, p = .896), after controlling for baseline HADS-D scores, body mass index, IBD phenotype, sex, and perceived stress. Likely due to lower power, results on FCAL (n = 31) were not statistically significant.

CONCLUSION

This study suggests that IBD patients with previous diagnosis of mood disorder may be at higher risk of inflammation-related depressive symptoms.

Link between depression and bone mineral density in Cooper Center Longitudinal Study: Indirect effects of vitamin D, inflammation, and physical activity

BACKGROUND

To examine the effect of depressive symptom severity on bone mineral density (BMD) and the potential mediators of the relationship.

METHOD

This study used data from n = 7273 participants in the Cooper Center Longitudinal Study at the Cooper Clinic in Dallas. Participants were included if they had data for all study variables, including left and right femoral neck (BMD), age, sex, body mass index, smoking status, antidepressant (SSRI/SNRI) use, standard alcoholic drinks consumed per week, and depressive symptom severity as measured with the Center for Epidemiological Studies-Depression (CESD)-10. To evaluate the effect of depressive symptoms on both L/R femur BMD, two multiple linear regression analyses were conducted. To examine effects of vitamin D, high sensitivity C-reactive protein (hs-CRP), and physical activity (MET units) on the relationship between depressive symptom severity and BMD, parallel mediation analyses were conducted.

RESULTS

Depressive symptom severity (CES-D 10 score) significantly predicted both L/R BMD (L: β = -0.048, R: β = -0.047, both p ≤ .001). Only physical activity significantly mediated the relationship between depressive symptom severity and L/R BMD (L: β = -0.008, 95 % CI [-0.011, -0.005]; R: β = -0.007, 95 % CI [-0.010, -0.005]).

LIMITATIONS

The sample may not be generalizable to all patient populations.

CONCLUSION

Depressive symptom severity was inversely related to both L/R femur BMD in a large cohort of relatively healthy adults. Physical activity, but not vitamin D or hs-CRP, mediated this relationship. Future research might examine the effect of physical activity interventions both on depression and BMD.

IMPACT STATEMENT

We certify that this work is both novel and confirmatory of recent clinical research (Lee et al., 2015; Amsterdam and Hooper, 1998; Hlis et al., 2018; Wainstein et al., 2016; Blair et al., 1989; Farrell et al., 2022; Ainsworth et al., 2011). We demonstrated a negative relationship between depression and BMD in a large cohort of adults and expanded on previous findings by demonstrating that physical activity acts as a mediator of this relationship. Physical activity is known to stimulate osteogenesis in osteoporotic patients, and this study further expands on its role in depressive symptoms in this population.

KEY POINTS

The cross-sectional relationship among omega-3 fatty acid levels, cardiorespiratory fitness, and depressive symptoms from the Cooper Center Longitudinal Study

OBJECTIVE

Omega-3 polyunsaturated fatty acids (omega-3 PUFAs) are implicated in numerous illnesses including depression. The literature is mixed regarding the relationship between n-3 PUFA levels and depression, and studies based on self-reported dietary n-3 PUFA intake may not accurately reflect in vivo levels.

METHOD

The current cross-sectional analysis examined the relationship between erythrocyte levels (eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) and depressive symptoms (Center for Epidemiologic Studies Depression Scale; CESD), adjusting for health-related factors and omega-3 supplement use in 16,398 adults assessed at the Cooper Clinic in Dallas, Texas for preventative medical examinations between April 6, 2009, and September 1, 2020. A three-stage hierarchical linear regression was conducted to examine the EPA and DHA levels on CES-D before and after inclusion of cardiorespiratory fitness (CRF) and high sensitivity C-reactive protein (hs-CRP) in the model.

RESULTS

DHA level, but not EPA level, was significantly associated with CES-D scores. Taking omega-3 supplements was associated with lower CES-D scores even when adjusting for CRF, while hs-CRP was non-significantly associated with CES-D scores. These findings suggest that DHA levels are related to depressive symptom severity. Omega-3 PUFA supplement use was associated with lower CES-D scores when controlling for EPA and DHA levels.

CONCLUSION

The findings from this cross-sectional study suggest that lifestyle and/or other contextual factors unrelated to EPA and DHA levels may also be associated with depressive symptom severity. Longitudinal studies are needed to evaluate the role of health-related mediators among these relationships.

Significantly elevated phosphatidylethanol levels in recent suicide attempters, but not in depressed controls and healthy volunteers

INTRODUCTION

Suicide is a complex transdiagnostic phenomenon. It is strongly associated with, but not exclusive to major depressive disorder (MDD). Hazardous alcohol drinking has also been linked to an increased risk of suicidal behaviours, however, it is often underreported. The study aimed to evaluate whether an objective measure of chronic alcohol use, phosphatidylethanol (PEth) could be useful as a biomarker in clinical practice.

METHOD

ology. The present case-control multi-centric study recruited 156 participants into three study groups: 52 patients treated for major depressive disorder (MDD), 51 individuals immediately following a suicide attempt (SA), and 53 volunteers. Sociodemographic data, medical history, and laboratory data, including PEth concentrations and C-reactive protein levels, were collected from study participants.

RESULTS

PEth concentrations were the highest in suicide attempters (232,54 ± 394,01 ng/ml), followed by patients with MDD (58,39 ± 135,82 ng/ml), and the control group (24,45 ± 70,83 ng/ml) (Kruskall Wallis χ2 = 12.23, df = 2, p = .002). In a multinomial logistic regression model with adjustments, PEth concentration was able to predict belonging to suicide attempters' group, but not to depression group (p = .01). Suicide attempters were also more likely to underreport their recent alcohol consumption.

LIMITATIONS

We did not analyze SA methods, psychiatric comorbidity and several other factors that might be associated with PEth levels, such as body mass index, race, and haemoglobin levels. Sample recruited in hospital settings may not be representative of the whole population. The results of this adult-only study cannot be generalized to adolescents.

CONCLUSIONS

PEth levels in recent suicide attempters significantly exceeded those of patients with MDD and controls. Suicide attempters also were more likely to underreport their alcohol consumption when questioned about their consuption. PEth might be an interesting biomarker to evaluate individuals at risk of SA.

Neuroinflammation in HIV-associated depression: evidence and future perspectives

People living with HIV face a high risk of mental illness, especially depression. We do not yet know the precise neurobiological mechanisms underlying HIV-associated depression. Depression severity in the general population has been linked to acute and chronic markers of systemic inflammation. Given the associations between depression and peripheral inflammation, and since HIV infection in the brain elicits a neuroinflammatory response, it is possible that neuroinflammation contributes to the high prevalence of depression amongst people living with HIV. The purpose of this review was to synthesise existing evidence for associations between inflammation, depression, and HIV. While there is strong evidence for independent associations between these three conditions, few preclinical or clinical studies have attempted to characterise their interrelationship, representing a major gap in the literature. This review identifies key areas of debate in the field and offers perspectives for future investigations of the pathophysiology of HIV-associated depression. Reproducing findings across diverse populations will be crucial in obtaining robust and generalisable results to elucidate the precise role of neuroinflammation in this pathophysiology.

Psychiatric symptoms are not associated with circulating CRP concentrations after controlling for medical, social, and demographic factors

Elevated serum concentrations (>3 mg/L) of the acute-phase protein, C-reactive protein (CRP), is used as a clinical marker of inflammation and is reported to be a strong risk factor for cardiovascular disease. In psychiatric populations, CRP concentration is reported to be higher in depressed versus healthy individuals. Positive associations between CRP and depression have been established in both clinical and community samples, but effect sizes are attenuated after controlling for confounding variables. Similarly, emerging research has begun to draw a link between inflammation, symptoms of anxiety, and substance abuse. Given the high level of comorbid anxiety and substance use disorders in many depressed populations, this study examined whether depression (Patient Health Questionnaire 9 [PHQ-9]) and substance use-related (Drug Abuse Screening Test [DAST]) symptoms were associated with CRP concentrations in the blood after adjusting for relevant medical, social, and demographic covariates in a large sample undergoing screening for several transdiagnostic psychiatric research studies. A total of 1,724 participants were analyzed for association of CRP with variables using multivariate linear regression. An unadjusted model with no covariates showed that PHQ-9 was significantly associated with CRP in All (β = 0.125), Female (β = 0.091), and Male (β = 0.154) participants, but DAST was significantly associated with CRP in males only (β = 0.120). For the adjusted model, in both males and females, mood-stabilizer treatment (β = 0.630), opioid medication (β = 0.360), body mass index (β = 0.244), percent body fat (β = 0.289), nicotine use (β = 0.063), and self-reported sleep disturbance (β = 0.061) were significantly associated with increased CRP concentrations. In females, oral contraceptive use (β = 0.576), and waist-to-hip ratio (β = 0.086), and in males, non-steroidal anti-inflammatory drug use (β = 0.367) were also associated with increased CRP concentrations. There was no significant association between CRP and individual depressive, anxiety, or substance use-related symptoms when covariates were included in the regression models. These results suggest that associations between circulating CRP and the severity of psychiatric symptoms are dependent on the type of covariates controlled for in statistical analyses.

A game changer for bipolar disorder diagnosis using RNA editing-based biomarkers

In clinical practice, differentiating Bipolar Disorder (BD) from unipolar depression is a challenge due to the depressive symptoms, which are the core presentations of both disorders. This misdiagnosis during depressive episodes results in a delay in proper treatment and a poor management of their condition. In a first step, using A-to-I RNA editome analysis, we discovered 646 variants (366 genes) differentially edited between depressed patients and healthy volunteers in a discovery cohort of 57 participants. After using stringent criteria and biological pathway analysis, candidate biomarkers from 8 genes were singled out and tested in a validation cohort of 410 participants. Combining the selected biomarkers with a machine learning approach achieved to discriminate depressed patients (n = 267) versus controls (n = 143) with an AUC of 0.930 (CI 95% [0.879-0.982]), a sensitivity of 84.0% and a specificity of 87.1%. In a second step by selecting among the depressed patients those with unipolar depression (n = 160) or BD (n = 95), we identified a combination of 6 biomarkers which allowed a differential diagnosis of bipolar disorder with an AUC of 0.935 and high specificity (Sp = 84.6%) and sensitivity (Se = 90.9%). The association of RNA editing variants modifications with depression subtypes and the use of artificial intelligence allowed developing a new tool to identify, among depressed patients, those suffering from BD. This test will help to reduce the misdiagnosis delay of bipolar patients, leading to an earlier implementation of a proper treatment.

C-Reactive Protein as a Biomarker for Major Depressive Disorder?

The etiopathogenesis of depression is not entirely understood. Several studies have investigated the role of inflammation in major depressive disorder. The present work aims to review the literature on the association between C-Reactive Protein (CRP) and depression. A systematic review was performed for the topics of ‘CRP’ and ‘depression’ using the PubMed database from inception to December 2021. Fifty-six studies were identified and included in the review. Evidence suggested the presence of dysregulation in the inflammation system in individuals with depression. In most studies, higher blood CRP levels were associated with greater symptom severity, a specific pattern of depressive symptoms, and a worse response to treatment. Moreover, about one-third of depressed patients showed a low-grade inflammatory state, suggesting the presence of a different major depressive disorder (MDD) subgroup with a distinct etiopathogenesis, clinical course, treatment response, and prognosis, which could benefit from monitoring of CRP levels and might potentially respond to anti-inflammatory treatments. This work provides robust evidence about the potential role of CRP and its blood levels in depressive disorders. These findings can be relevant to developing new therapeutic strategies and better understanding if CRP may be considered a valuable biomarker for depression.

Serum Low-Density Lipoprotein Cholesterol Levels and Depressive Mood in Korean Adults: A Nationwide Population-Based Study

Background

The association between serum cholesterol levels and depression has been studied extensively; however, results are inconsistent. This study aimed to investigate the association between low-density lipoprotein cholesterol (LDL-C) levels and depressive symptoms among Korean adults.

Methods

This cross-sectional study used data obtained from the 2007–2015 Korea National Health and Nutrition Examination Survey. In total, 40,904 adults were included in the final analysis. Participants were categorized into five groups according to their LDL-C levels, using the Korean guidelines for dyslipidemia. Symptoms of depression were evaluated using a self-reported questionnaire. Weighted logistic regression was used to examine the relationship between LDL-C levels and self-reported depressive symptoms.

Results

Compared with the intermediate category, the lowest (<70 mg/dL) and highest (≥160 mg/dL) LDL-C categories were associated with depressive symptoms, after adjusting for potential confounding factors (odds ratio [OR], 1.191; 95% confidence interval [CI], 1.008–1.409; OR, 1.241; 95% CI, 1.073–1.435, respectively). The highest LDL-C category was positively associated with depressive symptoms in those who were middle-aged, female, had a low body mass index, and taking or not taking dyslipidemia medications.

Conclusion

A U-shaped association was identified between LDL-C categories and self-reported depressive symptoms. Our findings suggest that LDL-C levels that are too low or too high are associated with self-reported depressive symptoms. Further prospective studies are needed to determine the causal relationship of this association.

Psychosocial and Biological Outcomes of Immersive, Mindfulness-Based Treks in Nature for Groups of Young Adults and Caregivers Affected by Cancer: Results from a Single Arm Program Evaluation from 2016-2021

The COVID-19 pandemic has left many individuals suffering from “connection deficit disorder” given changes to the way we work, go to school, socialize, and engage in daily activities. Young adults affected by cancer between the ages of 18–39 have known this connection deficit long before the pandemic. Being diagnosed and treated for cancer during this time can significantly disrupt engagement in important educational, career, social, and reproductive pursuits, and contribute to increased stress, anxiety, depression, and other negative outcomes. Experiencing meaningful connection—with nature, with peers who understand, and with oneself, may help assuage this adverse effect of disconnect. A single arm within-subjects program evaluation was conducted to examine outcomes following participation in immersive, multi-night, mindfulness-based treks in nature in a sample of young adults (n = 157) and caregivers (n = 50) affected by cancer from 2016–2021. Pre to post-trek changes included significant (p < 0.001) self-reported improvements in feeling connected to nature (d = 0.93–0.95), peers (d = 1.1–1.3), and oneself (d = 0.57–1.5); significant (p < 0.001) improvements on PROMIS Anxiety (d = 0.62–0.78), Depression (d = 0.87–0.89), and Sleep Disturbance (d = 0.37–0.48) short forms; and significant (p < 0.05) changes in pro-inflammatory biomarkers (d = 0.55–0.82). Connection-promoting experiences like this have the potential to improve health and wellbeing in this population and serve as a model for others.

Depression: Biological markers and treatment

Nowadays depression is considered as a systemic illness with different biological mechanisms involved in its etiology, including inflammatory response, hypothalamic-pituitary-adrenal (HPA) axis dysregulation and neurotransmitter and neurotrophic systems imbalance. Novel "omics" approaches, such as metabolomics and glycomics provide information about altered metabolic pathways and metabolites, as well as disturbances in glycosylation processes affected by or causing the development of depression. The clinical diagnosis of depression continues to be established based on the presence of the specific symptoms, but due to its heterogeneous underlying biological background, that differs according to the disease stage, there is an unmet need for treatment response biomarkers which would facilitate the process of appropriate treatment selection. This paper provides an overview of the role of major stress response system, the HPA axis, and its dysregulation in depression, possible involvement of neurotrophins, especially brain-derived neurotrophic factor, glial cell line-derived neurotrophic factor and insulin-like growth factor-1, in the development of depression. Article discusses how activated inflammation processes and increased cytokine levels, as well as disturbed neurotransmitter systems can contribute to different stages of depression and could specific metabolomic and glycomic species be considered as potential biomarkers of depression. The second part of the paper includes the most recent findings about available medical treatment of depression. The described biological factors impose an optimistic conclusion that they could represent easy obtainable biomarkers potentially predicting more personalized treatment and diagnostic options.

An Association Between the Inflammatory Biomarker GlycA and Depressive Symptom Severity

OBJECTIVE

The underlying mechanisms of depression remain unclear; however, current literature suggests a relationship between inflammation and depression. The association between the inflammatory biomarker high-sensitivity C-reactive protein (hs-CRP) and depression has been previously investigated, but the relationship between GlycA, a novel spectroscopic inflammatory biomarker, and depression does not appear to have been examined.

METHODS

Data were obtained from The Dallas Heart Study (DHS, conducted between 2000 and 2002), which consisted of a large community-based sample of Dallas County residents (N = 3,033). Depressive symptom severity was assessed with the Quick Inventory of Depressive Symptomatology-Self-Report (QIDS-SR). It was hypothesized that the serum GlycA level would be a statistically significant predictor of QIDS-SR scores after control for demographic covariates. Multiple linear regression was used to assess the relationship between GlycA level and QIDS-SR scores. The role of hs-CRP in predicting QIDS-SR scores was also explored.

RESULTS

GlycA level was a statistically significant positive predictor of QIDS-SR score (β = .053, P = .038) with control for sex, age, antidepressant use, ethnicity, smoking status, drinking status, body mass index, and years of education. In a subset of adults with moderate-to-severe depression, GlycA level was not associated with QIDS-SR scores. Additionally, hs-CRP level was not a statistically significant predictor of QIDS-SR scores.

CONCLUSIONS

This study found a positive association between the inflammatory biomarker GlycA, but not hs-CRP, and depressive symptom severity in a large multiethnic and multiracial community-based sample. Thus, these results provide the first indication that GlycA may be a potentially useful novel biomarker of depression.