Association between omega-3 fatty acids and depressive symptoms among patients with established coronary artery disease: data from the Heart and Soul Study

Omega-3 PUFAs' efficacy in the therapy of coronary artery disease combined with anxiety or depression: a meta-analysis

Objective

The evidence demonstrates that omega-3 polyunsaturated fatty acids (omega-3 PUFAs) protect the cardiovascular system and alleviate anxious or depressive situations. We conducted a meta-analysis to evaluate the effectiveness of omega-3 PUFAs in the treatment of anxiety or depressive states in patients with coronary artery disease.

Methods

This meta-analysis analyzed data from randomized controlled trials to determine the efficacy of omega-3 PUFAs alone or in combination with conventional psychotropic medications in coronary artery disease patients suffering from anxiety or depression. Primary outcomes included changes in depression scores, the Beck Anxiety Inventory (BAI) scores, and the omega-3 index.

Results

Included were 6 trials involving 2,570 participants. Compared to controls,omega-3 PUFAs did not improve depression or anxiety {depression: [SMD=0.09 (95% CI: -0.07, 0.26)], anxiety [BAI: SMD=0.07 (95% CI: -0.17, 0.32)]}; For the results of the subgroup analyses, analyzed by different types of depression scales, four studies used the HAMD scale [SMD=0.19 (95% CI: -0.20, 0.58)]; 5 studies used the BDI-II scale [SMD=0.01 (95% CI: -0.07, 0.09)], all of which indicated no decrease in depression scale scores; analyzed by different types of intervention, 3 studies used the omega-3 PUFAs group [SMD=0.24 (95% CI: -0.26, 0.74)]; 2 studies used sertraline + omega-3 PUFAs [SMD=-0.08 (95% CI: -0.46, 0.31)], and the omega-3 index was elevated [SMD=1.33 (95% CI: 0.18, 2.49)], suggesting that the body's omega-3 content was indeed replenished but did not change the patient's depressive state; analyzed by different courses of therapy, a 10-week course of therapy [SMD=0.02 (95% CI: -0.23, 0.26)] and a 12-week course of therapy [SMD=0.40 (95% CI: -0.40, 1.20)] both resulted in a lack of improvement in depressive symptoms.

Conclusion

According to the available evidence, omega-3 PUFAs do not alleviate anxiety or depression in coronary artery disease patients.

Systematic Review Registration

https://www.crd.york.ac.uk/PROSPERO/, identifier CRD42023391259.

Importance of EPA and DHA Blood Levels in Brain Structure and Function

Brain structure and function depend on a constant and sufficient supply with eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) by blood. Blood levels of EPA and DHA reflect dietary intake and other variables and are preferably assessed as percentage in erythrocytes with a well-documented and standardized analytical method (HS-Omega-3 Index^®). Every human being has an Omega-3 Index between 2 and 20%, with an optimum of 8–11%. Compared to an optimal Omega-3 Index, a lower Omega-3 Index was associated with increased risk for total mortality and ischemic stroke, reduced brain volume, impaired cognition, accelerated progression to dementia, psychiatric diseases, compromises of complex brain functions, and other brain issues in epidemiologic studies. Most intervention trials, and their meta-analyses considered EPA and DHA as drugs with good bioavailability, a design tending to produce meaningful results in populations characterized by low baseline blood levels (e.g., in major depression), but otherwise responsible for many neutral results and substantial confusion. When trial results were evaluated using blood levels of EPA and DHA measured, effects were larger than comparing EPA and DHA to placebo groups, and paralleled epidemiologic findings. This indicates future trial design, and suggests a targeted use EPA and DHA, based on the Omega-3 Index.

Heart Rate Variability and Omega-3 Index in Euthymic Patients with Bipolar Disorders

Background:

Affective disorders are associated with an increased risk of cardiovascular disease, which, at least partly, appears to be independent of psychopharmacological treatments used to manage these disorders. Reduced heart rate variability (SDNN) and a low Omega-3 Index have been shown to be associated with increased risk for death after myocardial infarction. Therefore, we set out to investigate heart rate variability and the Omega-3 Index in euthymic patients with bipolar disorders.

Methods:

We assessed heart rate variability (SDNN) and the Omega-3 Index in 90 euthymic, mostly medicated patients with bipolar disorders (Bipolar-I, Bipolar-II) on stable psychotropic medication, free of significant medical comorbidity and in 62 healthy controls. Heart rate variability was measured from electrocardiography under a standardized 30 minutes resting state condition. Age, sex, BMI, smoking, alcohol consumption and caffeine consumption as potential confounders were also assessed.

Results:

Heart rate variability (SDNN) was significantly lower in patients with bipolar disorders compared to healthy controls (35.4 msec versus 60.7 msec; P < 0.0001), whereas the Omega-3 Index did not differ significantly between the groups (5.2% versus 5.3%). In a linear regression model, only group membership (patients with bipolar disorders versus healthy controls) and age significantly predicted heart rate variability (SDNN).

Conclusion:

Heart rate variability (SDNN) may provide a useful tool to study the impact of interventions aimed at reducing the increased risk of cardiovascular disease in euthymic patients with bipolar disorders. The difference in SDNN between cases and controls cannot be explained by a difference in the Omega-3 Index.

The emerging role of omega-3 fatty acids as a therapeutic option in neuropsychiatric disorders

The prevalence of neurologic and psychiatric diseases has been increasing for decades and, given the moderate therapeutic efficacy and safety profile of existing pharmacological treatments, there is an urgent need for new therapeutic approaches. Nutrition has recently been recognized as an important factor for the prevention and treatment of neuropsychiatric disorders. The omega-3 polyunsaturated fatty acids (n-3 PUFAs) eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) play critical roles in neuronal cell function and neurotransmission as well as inflammatory and immune reactions that are involved in neuropsychiatric disease states. A large number of experimental and epidemiological studies provide a strong basis for interventional clinical trials that assessed the clinical efficacy of n-3 PUFAs in various neurological and psychiatric disorders. Most of these trials found beneficial effects of dietary supplementation with EPA and DHA, and no serious safety concerns have emerged. This review gives an introduction to recent findings on the clinical efficacy of n-3 PUFAs in various neuropsychiatric disorders and the underlying biochemical mechanisms. In addition, the reader will be enabled to identify common methodological weaknesses of clinical studies on n-3 PUFAs, and suggestions for the design of future studies are given.

Efficient generation of sFat-1 transgenic rabbits rich in n-3 polyunsaturated fatty acids by intracytoplasmic sperm injection

N-3 polyunsaturated fatty acids (n-3 PUFAs) have their first double bond at the third carbon from the methyl end of the fatty-acid chain and had been proven to be beneficial to human health. However, mammals cannot produce n-3 PUFAs by themselves because they lack the n-3 fatty-acid desaturase (Fat-1) gene. Thus, the possibility of producing sFat-1 transgenic rabbits was explored in this study. The transgenic cassette of pPGK1-sFat-1-CMV-EGFP was constructed and transgenic rabbit embryos were produced by intracytoplasmic sperm injection (ICSI). When 123 EGFP-positive embryos at the 2-8-cell stage were transplanted into the oviduct of four oestrous-synchronised recipients, two of them became pregnant and gave birth to seven pups. However, transfer of embryos into the uterus of oestrous-synchronised recipients and oviduct or uterus of oocyte donor rabbits did not result in pregnancy. The integration of the sFat-1 gene was confirmed in six of the seven live pups by PCR and Southern blot. The expression of the sFat-1 gene in the six transgenic pups was also detected by reverse transcription polymerase chain reaction (RT-PCR). Gas chromatography-mass spectrometry analysis revealed that transgenic rabbits exhibited an ~15-fold decrease in the ratio of n-6:n-3 PUFAs in muscle compared with wild-type rabbits and non-transgenic rabbits. These results demonstrate that sFat-1 transgenic rabbits can be produced by ICSI and display a low ratio of n-6:n-3 PUFAs.

Baseline blood levels of omega-3 and depression remission: a secondary analysis of data from a placebo-controlled trial of omega-3 supplements

OBJECTIVE

Depression is associated with low red blood cell (RBC) levels of 2 omega-3 fatty acids, eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), suggesting that omega-3 supplements might improve depression. However, clinical trials have produced mixed results. The purpose of this secondary analysis of data from a randomized controlled trial was to determine whether baseline blood levels of omega-3, which are known to vary widely among individuals, predict depression outcomes.

METHOD

The percentages of EPA, DHA, and the omega-6 arachidonic acid (AA) were measured in RBCs at baseline and posttreatment in 122 participants with DSM-IV major depression who were randomly assigned between May 2005 and December 2008 to receive either 50 mg/d of sertraline and a daily dosage of 930 mg EPA/750 mg DHA or sertraline plus placebo. Associations between baseline omega-3 RBC levels and remission of depression (17-item Hamilton Depression Rating Scale score ≤ 7) were analyzed by treatment arm.

RESULTS

Among participants in the omega-3 arm, baseline RBC levels of EPA + DHA (P = .002) and the EPA + DHA:AA ratio (P = .003) were significantly higher among those whose depression subsequently remitted compared with those whose depression did not remit. No associations were detected in the sertraline plus placebo arm. Baseline levels of EPA (P = .03) and the EPA + DHA:AA ratio (P = .04) moderated the relationship between treatment arm and depression outcomes.

CONCLUSIONS

High baseline RBC levels of EPA and DHA and a high EPA + DHA:AA ratio predict favorable depression outcomes in patients receiving omega-3 supplements. Omega-3 supplementation may be an effective treatment for depression, but the requisite dosage and duration of treatment may depend on the patient's baseline level of omega-3 fatty acids.

TRIAL REGISTRATION

ClinicalTrials.gov identifier: NCT00116857.

Associations between omega fatty acid consumption and depressive symptoms among individuals seeking behavioural weight loss treatment

OBJECTIVE

The typical Western diet is deficient in omega-3 and high in omega-6 fatty acids (FAs). These FAs may play a role in depressive symptoms via inflammatory processes, especially in the context of obesity, a pro-inflammatory state. This study investigated associations between omega-3 and omega-6 FA intake and depressive symptoms in adults seeking behavioural weight loss treatment (BWLT).

METHODS

One hundred eighty-eight persons with overweight or obesity (83.50% women, 93.10% White, 55.01 ± 10.09 years old, body mass index 36.02 ± 15.79 kg/m) seeking BWLT completed the Block Food Frequency Questionnaire, which provides estimates of dietary FA intake, daily total energy intake (TEI) and macronutrient composition of the diet. Depressive symptoms were measured via the Center for Epidemiological Studies Depression Scale. Correlation and linear regression estimated associations between depressive symptoms and FAs.

RESULTS

On average, participants reported consuming 1866.2 ± 665.1 kcals/d, with 38% of TEI from fat and an omega-6:3 ratio of 9.2 (13.9 g omega-6 to 1.5 g omega-3). In univariate models, omega-6 intake was associated with depressive symptoms (r = .182, p = .012); however, this association was no longer statistically significant after controlling for TEI. Omega-3 intake was not associated with depressive symptoms.

CONCLUSION

The expected association between omega-3 and omega-6 FAs and depressive symptoms was largely unsupported. A robust association between FA intake and depressive symptoms may have been masked by a high level of chronic inflammation in this sample caused by excess weight and overall poor diet. Additional research is needed to determine whether BWLT improves FA intake, and whether associations between FA intake and depressive symptoms are strengthened after successful weight loss and improved diet.

Omega-3 fatty acid biomarkers and subsequent depressive symptoms

OBJECTIVE

We sought to determine the relationship between the omega-3 fatty acid content of red blood cell membranes (RBC), in particular docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA), and baseline and new-onset depressive symptoms in post-menopausal women. We secondarily sought to characterize the association between dietary omega-3 fatty acid intake and depressive symptomatology.

METHODS

Study participants included 7086 members of the Women's Health Initiative Memory Study (aged 63-81 years) who had an assessment of RBC omega-3 fatty acid concentrations at the baseline screening visit. Depressive symptoms at baseline and follow-up were characterized using the Burnam eight-item scale for depressive disorders (Center for Epidemiologic Studies Depression Scale/Diagnostic Interview Schedule short form) and secondarily additionally inferred by antidepressant medication use.

RESULTS

In multivariable-adjusted models, our primary exposure, RBC DHA + EPA, was not related to depressive symptoms by any measure at baseline or follow-up, nor were RBC total omega-3, DHA, or EPA (all p > 0.2). In contrast, dietary intake of omega-3 was positively associated with depressive symptoms at baseline (adjusted odds ratio 1.082, 95% confidence interval 1.004-1.166; p = 0.04 for dietary DHA + EPA and Burnam score ≥0.06), although this generally did not persist at follow-up.

CONCLUSION

No relationship between RBC omega-3 levels and subsequent depressive symptoms was evident, and associations between dietary omega-3 and depressive symptoms were variable. Biomarkers of omega-3 status do not appear to be related to risk of new depression in post-menopausal women.

Peripheral artery disease and risk of cardiovascular events in patients with coronary artery disease: insights from the Heart and Soul Study

Among patients with coronary artery disease (CAD), those with peripheral artery disease (PAD) have a greater vulnerability to cardiovascular (CV) events than those with CAD alone. In a prospective cohort study of patients with CAD, we evaluated potential mechanisms that might explain the adverse CV outcomes associated with PAD. We performed a prospective cohort study of 1018 patients with stable CAD who were recruited from 2000 to 2002. Incident symptomatic PAD events were adjudicated during a follow-up period of 7.2 ± 2.6 years. We used Cox proportional hazards models to evaluate the association between incident symptomatic PAD events and subsequent risk of CV events or death. Models were adjusted for demographics, traditional risk factors, inflammation, insulin resistance and health behaviors. Among the 1018 patients, 50 patients who did not report a history of PAD at baseline suffered incident symptomatic PAD events during the follow-up period. Those patients had a higher risk of subsequent CV events and death compared to those who did not develop PAD. After adjustment for traditional risk factors, symptomatic PAD events remained associated with a 70% increased risk of subsequent CV events (adjusted HR 1.7; 95% CI 1.0, 2.9; p = 0.04) and an 80% increased risk of death (adjusted HR 1.8; 95% CI 1.2, 2.7; p = 0.006). Inflammatory biomarkers were the strongest risk factor contributing to the excess risk. In a contemporary cohort of patients with CAD, incident symptomatic PAD events were associated with an increased risk for subsequent CV events. The increased vulnerability to CV events was partially explained by shared CV risk factors and inflammation.

Type D personality as a cardiovascular risk marker in the general population: results from the Gutenberg health study

BACKGROUND

Type D personality is considered as an independent risk factor for morbidity and mortality in cardiovascular patients and a vulnerability factor for distress in the general population. Because representative community studies are rare, we sought to determine the prevalence of type D personality and its relationship with demographic characteristics, different features of mental disorders, cardiovascular risk factors, health behavior, endothelial function and cardiovascular biomarkers in the general population.

METHODS

The prevalence of type D personality and its correlates were analyzed cross-sectionally in a population-based sample of 5,000 Mid-Europeans aged 35-74 years from the Gutenberg Health Study.

RESULTS

The prevalence of type D personality was 22.2% without remarkable differences in sex distribution. Type D subjects were characterized by lower socioeconomic status, lack of a partnership, increased depression, anxiety, depersonalization and health care utilization. Despite its strong association with mental disorders, type D personality emerged as psychometrically distinct. Although type D personality was independently associated with coronary heart disease (OR = 1.54, p = 0.044), no associations with traditional cardiovascular risk factors were found independently from depression or anxiety.

CONCLUSIONS

Although type D personality is strongly associated with depression, anxiety, impaired mental and somatic health status, and increased health care utilization, the type D construct seems to comprise dysfunctional personality patterns not covered by depression and anxiety scales. Beyond these associations, the pathways of the cardiotoxic impact of type D personality remain to be elucidated. There is a need for prospective population studies on potential links between type D personality and cardiac disease.

Cross-sectional but not longitudinal association between n-3 fatty acid intake and depressive symptoms: results from the SU.VI.MAX 2 study

Findings regarding the association between n-3 polyunsaturated fatty acid (PUFA) status and depression are conflicting. Thus, the authors studied associations between PUFA intake and depressive symptoms. In 1996, depressive symptoms were assessed in a subsample of participants from the Supplementation with Antioxidant Vitamins and Minerals (SU.VI.MAX) Study using the Center for Epidemiologic Studies Depression Scale (CES-D). In 2007-2009, information on CES-D score, history of depression, and use of antidepressant medication was obtained. Intakes of n-3 PUFAs were estimated from repeated 24-hour dietary records collected during 1994-1996. Subjects with depressive symptoms (cases) were identified using CES-D scores greater than 15 and/or antidepressant use. Logistic regression analyses were used. Cross-sectional (n = 2,744) and longitudinal (n = 1,235) associations between quartiles of PUFA intake and depressive symptoms were estimated. In cross-sectional analyses, quartile of n-3 PUFA intake was associated with lower odds of depressive symptoms (fourth quartile vs. first: odds ratio = 0.74, 95% confidence interval: 0.58, 0.95; P for trend = 0.001). No association between PUFA intake and incidence of depressive symptoms over 13 years was detected. This study provides new insights into the PUFA-depression link. While no association between n-3 PUFA intake and incidence of depressive symptoms was detected, an association was observed in cross-sectional analyses, which may reflect unhealthy dietary patterns among subjects with depressive symptoms.

The omega-3 index: clinical utility for therapeutic intervention

Red blood cell levels of eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) are a reflection of tissue levels and are determined by a complex interplay of metabolism and nutrition. Low levels of EPA+DHA in erythrocytes are associated with increased risk for sudden cardiac death. If levels of EPA+DHA in erythrocytes are determined using a strictly defined and standardized method, then the clinical significance of differing levels (previously defined in major research studies using this methodology) may be understood and applied in patient care. The Omega-3 Index, which is the EPA+DHA content of erythrocytes expressed as a percent of total identified fatty acids, was originally suggested as a marker of increased risk for death from coronary heart disease, but it can also be viewed as an actual risk factor, playing a pathophysiologic role in the disease. Optimal levels appear to be 8% or greater. At this stage of its development, the Omega-3 Index appears to fulfill many of the requirements for both a risk marker and a risk factor. Using the Omega-3 Index in the design of clinical studies might allow for a more efficient use of research resources.

The impact of depression in heart disease

Depression and heart disease affect millions of people worldwide. Studies have shown that depression is a significant risk factor for new heart disease and that it increases morbidity and mortality in established heart disease. Many hypothesized and studied mechanisms have linked depression and heart disease, including serotonergic pathway and platelet dysfunction, inflammation, autonomic nervous system and hypothalamic-pituitary-adrenal axis imbalance, and psychosocial factors. Although the treatment of depression in cardiac patients has been shown to be safe and modestly efficacious, it has yet to translate into reduced cardiovascular morbidity and mortality. Understanding the impact and mechanisms behind the association of depression and heart disease may allow for the development of treatments aimed at altering the devastating consequences caused by these comorbid illnesses.

Association of n-3 long-chain PUFA and fish intake with depressive symptoms and low dispositional optimism in older subjects with a history of myocardial infarction

Individuals with CHD are at increased risk of poor mental well-being. Dietary intake of EPA and DHA, the main n-3 fatty acids from fish, may be beneficial to mental well-being. We examined the association of EPA+DHA and fish intake with mental well-being in 644 participants, aged 60–80 years, with a history of myocardial infarction. Habitual food intake was assessed with a 203-item FFQ. Depressive symptoms were assessed with the self-report geriatric depression scale, and dispositional optimism was assessed with the revised life orientation test (LOT-R) and a four-item questionnaire (4Q). In Cox-regression models modified for cross-sectional analyses, we adjusted for sex, age, energy intake, BMI, family history of depression, education, marital status, smoking, physical activity and intake of saturated fat, alcohol and fibre. Compared with the lower tertile, subjects in the higher tertile of EPA+DHA intake had a lower prevalence of depressive symptoms, but this association was not statistically significant (prevalence ratio (PR) 0·78; 95 % CI 0·50, 1·22, P-trend 0·27). The higher tertile of EPA+DHA intake was positively associated with dispositional optimism measured with the 4Q (PR 0·69; 95 % CI 0·46, 1·03, P-trend 0·05), but not according to the LOT-R. Fish intake was not related to either depressive symptoms or dispositional optimism. In conclusion, intake of EPA+DHA was positively associated with dispositional optimism assessed with the 4Q, but not with optimism assessed with the LOT-R or with depressive symptoms.

Depressive symptoms, health behaviors, and risk of cardiovascular events in patients with coronary heart disease

CONTEXT

Depressive symptoms predict adverse cardiovascular outcomes in patients with coronary heart disease, but the mechanisms responsible for this association are unknown.

OBJECTIVE

To determine why depressive symptoms are associated with an increased risk of cardiovascular events.

DESIGN AND PARTICIPANTS

The Heart and Soul Study is a prospective cohort study of 1017 outpatients with stable coronary heart disease followed up for a mean (SD) of 4.8 (1.4) years.

SETTING

Participants were recruited between September 11, 2000, and December 20, 2002, from 12 outpatient clinics in the San Francisco Bay Area and were followed up to January 12, 2008.

MAIN OUTCOME MEASURES

Baseline depressive symptoms were assessed using the Patient Health Questionnaire (PHQ). We used proportional hazards models to evaluate the extent to which the association of depressive symptoms with subsequent cardiovascular events (heart failure, myocardial infarction, stroke, transient ischemic attack, or death) was explained by baseline disease severity and potential biological or behavioral mediators.

RESULTS

A total of 341 cardiovascular events occurred during 4876 person-years of follow-up. The age-adjusted annual rate of cardiovascular events was 10.0% among the 199 participants with depressive symptoms (PHQ score > or = 10) and 6.7% among the 818 participants without depressive symptoms (hazard ratio [HR], 1.50; 95% confidence interval, [CI], 1.16-1.95; P = .002). After adjustment for comorbid conditions and disease severity, depressive symptoms were associated with a 31% higher rate of cardiovascular events (HR, 1.31; 95% CI, 1.00-1.71; P = .04). Additional adjustment for potential biological mediators attenuated this association (HR, 1.24; 95% CI, 0.94-1.63; P = .12). After further adjustment for potential behavioral mediators, including physical inactivity, there was no significant association (HR, 1.05; 95% CI, 0.79-1.40; P = .75).

CONCLUSION

In this sample of outpatients with coronary heart disease, the association between depressive symptoms and adverse cardiovascular events was largely explained by behavioral factors, particularly physical inactivity.