The role of sense of coherence in reducing anxiety and depressive symptoms among patients at the first acute coronary event: A three-year longitudinal study

Highlights

• Patients with cardiovascular disease (CVD) are prone to psychological distress

• Psychological distress impacts the quality of life and health outcomes in CVD patients

• We tested the longitudinal associations between Sense of Coherence (SOC) and distress

• A strong SOC at baseline predicted a longitudinal decrease in anxiety and depression

• Interventions should aim to increase resilience resources such as SOC in CVD patients

Abstract

Objective

Although several studies suggest an association between psychological distress and increased morbidity and mortality in various cardiac populations, little is known about positive psychological resources, like Sense of Coherence (SOC), that may reduce distress. This longitudinal observational study aimed to test the hypothesis that a strong SOC predicted a longitudinal decrease in anxiety and depression in a sample of patients after their first acute coronary event.

Methods

A sample of 275 patients completed the Hospital Anxiety Depression Scale (HADS) and the SOC Scale at five time-points (at the baseline and after 6, 12, 24, and 36 months). Longitudinal trajectories of anxiety, depression, and SOC were examined through hierarchical (generalized) linear models, controlling for sociodemographic and clinical indicators.

Results

38.6% of patients experienced clinically relevant anxiety symptoms soon after the cardiovascular event, whereas only 20.8% experienced clinically relevant depressive symptoms. Anxiety symptoms decreased over time, plateaued, and then slightly increased, whereas depressive symptoms tended to be stable; these variables were positively associated during all time points. The SOC did not change over time; a strong SOC at baseline predicted decreased anxiety and depression.

Conclusion

Findings showed a strong relationship between SOC and symptoms of anxiety and depression, and they suggested the importance of a salutogenic approach in clinical practice and the relevance of interventions aimed at increasing resilience resources like the SOC in patients with cardiovascular diseases.

Introduction

Acute coronary syndrome (ACS) is the most common cause of morbidity and mortality in developed countries. Its burden is not only a health issue but also a growing economic and societal challenge [1,2].

Patients with ACS are prone to anxiety and depressive symptoms [3]. These symptoms can significantly impact patients' quality of life [4], leading to adverse effects on cardiac outcomes [5]. Although several studies have documented an association between depression, anxiety, and increased morbidity and mortality in a variety of cardiac populations [6,7], these psychopathological conditions have not yet achieved formal recognition as risk factors for poor prognosis in patients with ACS. Indeed, they are not currently recorded in the European Society of Cardiology (ESC) Atlas [2], nor are they among the World Health Organization's (WHO) targets for management for 2025 [8].

Knowing the levels and the long-term trajectories of anxiety and depression might help identify patients with higher psychological burdens and poorer cardiac outcomes. Recent studies suggested that patients with cardiovascular disease (CVD) may experience long-lasting symptoms of depression and anxiety that can impact the occurrence of major adverse cardiovascular events [9] and healthcare costs [10]. Palacios et al. [10] explored anxiety and depression trajectories in a sample of patients with established coronary heart disease over three years. They found that those with ‘chronic high’ and ‘worsening’ trajectories had significantly higher healthcare costs than those with a ‘stable low’ trajectory. Wang et al. [9] monitored anxiety and depression trajectories in a sample of newly diagnosed patients with coronary heart disease over three years and found that long-lasting depressive symptoms predicted the occurrence of increased and accumulating cardiovascular events.

The research focused on positive psychological factors that support health and well-being – the so-called salutogenic approach - is even more neglected. A key component of this approach is the sense of coherence (SOC). The SOC is an adaptive dispositional orientation that enables coping with adverse situations [11]. Individuals with a strong SOC are capable of understanding, handling, and making sense of a stressful situation or disease, and therefore they are capable of coping with it successfully. A systematic review showed that SOC scores negatively correlated with measures of depression and anxiety in adults with various health conditions [12]. Konttinen et al. [13] confirmed the negative correlation between SOC scores and measures of depression and anxiety in a sample of 4642 people representative of the general Finnish population. A recent study confirmed this correlation in a sample of 310 Spanish adults with cardiovascular risk factors, including a family history of CVDs, age over 55 years in men or over 65 years in women, a smoking habit, hypertension, diabetes, dyslipidemia, and obesity [14].

The association between SOC and depressive symptoms was also reported in patients with CVD [15,16]. However, little is known about SOC's potential to predict changes in anxiety and depression severity over time. Indeed, most studies focused on the longitudinal trajectories of health-related quality of life (HRQoL), showing that compared to patients with strong SOC, patients who had poor SOC had lower HRQoL over time [[17], [18], [19]]. Karlsson et al. [20] explored the relationship between SOC and HRQoL before and after coronary artery bypass surgery in 111 patients. The authors found that patients with stronger SOC felt less anxious and depressed 12 months after the surgery. Similarly, Norekvål et al. [21] carried out a longitudinal study focused on 145 women with myocardial infarction and found that patients with stronger SOC reported less anxiety and depression six months after hospitalization.

To the best of our knowledge, no study explored the possible predictive role of SOC on the longitudinal course of anxiety and depression in patients with ACS. The studies mentioned above [[17], [18], [19], [20], [21]] focused on the more general concept of HRQoL and took into consideration a timeline of 12 months or less, except one [19] that covered 28 months. Considering that previous studies suggested that patients with CVD may exhibit different long-term trajectories of depression and anxiety [10], it is crucial to extend the assessment period well beyond 12 months. Finally, only two studies focused on patients after the first diagnosis of myocardial infarction [17,21], while the others focused on patients with a previous diagnosis of CVD who underwent coronary angiography [19] or coronary artery bypass surgery [18,20]. Therefore, there seems to be a paucity of studies focused on patients at their first episode of ACS. Knowing the predictors of anxiety and depression trajectories could influence the occurrence of future cardiac episodes in these patients, considering, for example, that depression may predict an increase in the occurrence of a major cardiovascular event in patients with newly diagnosed coronary heart disease [9].

A further open question concerns the stability of the SOC over time. By definition, SOC represents a pervasive and stable orientation over time and across situations, although Antonovsky admitted that significant life crises during adulthood could undermine a weak SOC or temporarily weaken a strong SOC [22]. However, empirical investigation on the stability of SOC remains inconclusive [23]. A five-year follow-up study focused on a sample of 17,271 individuals from the general Finnish population showed that SOC varied during adulthood in response to numerous adverse life events [24]. In the context of studies focused on patients with CVD, Karlsson et al. [20] found that SOC changed from pre- to post- coronary artery bypass surgery, increasing in 14.7% and decreasing in 26.6% of patients. Kattainen et al. [18] found that SOC was stable among patients from pre- to post- coronary artery bypass grafting, whereas it decreased in patients from pre- to post-percutaneous transluminal coronary angioplasty. Conversely, Norekvål et al. [21] found that SOC did not change significantly six months after hospitalization for myocardial infarction.

Based on all these considerations, the aims of this study were manifold. Given the uncertainty of the previous studies regarding the stability of SOC in patients with CVDs [18,20,21] and the paucity of studies extending over three years, we aimed to test the preliminary hypothesis that SOC did not change over time in the present study sample. Second, we aimed to describe the trajectories of anxiety and depression throughout three years, following the evidence that patients with CVDs may experience different long-term trajectories of distress [9,10]. Third, we aimed to test the hypothesis that a strong SOC will play a significant role in predicting a longitudinal decrease in anxiety and depressive symptoms, in line with previous studies showing that SOC is a strong determinant of HRQoL in people experiencing a cardiovascular event [[17], [18], [19], [20], [21]]. Furthermore, we examined the extent to which baseline patient characteristics were associated with the trajectories of anxiety and depression, thus adjusting all analyses for potential sociodemographic and clinical confounders.