Introduction

Although depression is among the most significant single causes of disability worldwide [46], the treatment of depression remains a challenge on many levels [30]. Usually, selective serotonin reuptake inhibitors are prescribed as first-line treatment, in combination with other interventions, such as psychotherapy [24]. However, studies show that pharmacological interventions are not always successful. For instance, in some cases, antidepressants can be compared to a placebo [1]; [20]. Kolovos et al. [23] argue that treatment as usual (TAU)Footnote 1 is effective in about a third of the patients, while every tenth patient experiences a deterioration.

Due to the limitations of established treatment approaches, experts have increasingly been emphasizing the role of other factors in the treatment of depression, including the patient’s sense of meaning in life and the reasons why he or she might not have one [10, 11]. Therefore, studies of nonpharmacologic approaches that clinicians could use when working with patients with mild to moderate depression are becoming more common [24]. A search for evidence-based alternatives is also in line with many patients’ treatment preferences. In fact, Rajagopal et al. [32] speculate that if medication was the only option, many patients were likely to forgo treatment altogether. Behavioral interventions are often more acceptable and less stigmatizing. In recent years, spirituality, in particular, has been gaining recognition as a potential treatment modality [7].

The study aims to evaluate the evidence available in the literature that highlights the use of spirituality in the treatment of depression through a systematic review.

Background

Spirituality has been recognized as a broad and complex concept that has no uniform definition. The inconsistency can present a challenge when assessing its effects [13]. Sheldrake [37] distinguishes between three types of spirituality; (1) religious spirituality, (2) esoteric spirituality, and (2) secular spirituality. Comte-Sponville [9] describes atheistic spirituality that includes a sense of connectedness experienced when spending time outdoors. Although there is a link between spirituality and religiosity, spirituality can frequently be found outside of a religious framework and is a distinct category that encompasses the element of transcendence and the ability of a person to go beyond his or her current circumstances [41]. What all types of spirituality have in common is the quest for deeper meaning, which goes beyond the material and pragmatic experience of life. Some experts also argue that spirituality is an essential human need and is an integral part of an individual’s life. Therefore, it should be considered in psychotherapy [17, 41].

Spirituality is now increasingly used in the context of assessing a patient’s health and well-being, for example, when exploring the quality of life in patients with different chronic conditions [7, 41]. Several studies, originating both in the East and in the West, have pointed out that clinicians should try to include the patients’ spirituality in the management of their health condition [13]. Experts frequently view spirituality as a potential coping mechanism in the event of physical or psychological deterioration; therefore, many see it as a vital element of health care. Some studies found that better emotional and cognitive functioning can be observed in patients with higher meaning, peace, and faith [7]. Furthermore, a grave or uncertain diagnosis can stimulate the pursuit of spirituality in a person. However, this is usually more applicable to physical health [38].

Spirituality-based interventions have often been explored outside mental health. For instance, Delaney et al. [13] found it useful in the treatment of patients with cardiovascular diseases living in the community. Patients who participated in a 1-month intervention that focused on spirituality demonstrated an increase in the overall quality of life and a trend toward lower depression scores. Waraporn et al. [43] argued that a better understanding of spirituality could improve patient survival in people with chronic kidney disease and lead to better management of depression in this group of patients.

It has been recognized that spirituality can have a protective effect on depression [12]. Specifically, forgiveness of oneself and others is a statistically significant predictor of depression [42]. Baetz and Toews [2] argued that spiritual well-being plays a vital role in depression prevention and recovery.

Scientific literature often focuses on older adults with depression. Bamonti et al. [4] suggested that when working with older adults with depressive symptoms, spiritual beliefs should be included in a comprehensive psychosocial history in order to foster meaning in life. Their research found that treatment-seeking older adults with high levels of spirituality reported comparable levels of meaning in life to those without elevated depressive symptomatology, suggesting a significant relationship between spirituality and preservation of meaning in life. That has also been confirmed by Moon and Kim [27] who revealed that religiosity and spirituality had significant effects on depression and quality of life among older people in South Korea; religious people had a higher quality of life score. A Mexican study on aging also concluded that spirituality could be a useful resource for reducing depression and can act as a coping strategy to strengthen other areas of life [16].

Studies suggest that spirituality may contribute to favorable treatment responses among depressed patients, especially when the approach is compatible with the patient’s values and enhances treatment gains [19, 44]. Many authors support the use of spirituality with patients who do not exhibit severe psychotic symptoms and view it as a way to make sense of adverse situations and get solace outside the treatment room [44]. In addition, it has been documented that patients with depression are expressing a desire to include spirituality in their treatment. Some patients believe that integrating spirituality could increase support, acceptance, and comfort for them [40].

The literature also includes a more negative aspect of spirituality; that is, some individuals can interpret the reasons for depression in a lack of a spiritual connection, for instance, being abandoned or punished by God or experiencing a “loss of faith” [14, 39, 45]. Sorajjkool and colleagues [39] write about how depression can create a deep sense of spiritual disconnection and a deep yearning for a sense of meaning.

Although the link between spirituality and mental health has been recognized in the literature, we do not know much about the specific elements of spirituality-based treatments that can have a therapeutic value. Even though spirituality might have the potential to importantly influence the outcomes of treatment and increase the quality of life of patients with depression, knowledge on how to best include spirituality in the treatment process is scarce.

The research questions driving our study were:

  • RQ1: What are some of the elements of a spirituality-based treatment that can have a therapeutic value for a patient with depression?

  • RQ2: How could spirituality be included in the treatment of patients with depression?

Methods

We undertook a systematic review of research that met the following inclusion criteria: (a) quantitative, qualitative or mixed studies, (b) published between 2000 and 2018; (c) included people with a primary diagnosis of depression, and (d) scientifically evaluated therapeutic interventions that included elements of spirituality. Although the emphasis was on papers that included original qualitative or quantitative data collection and analysis, opinion pieces and literature reviews were not explicitly excluded in the first stage of the search as they were considered a potential source of bibliography. However, we did not include reviews or opinion pieces with no original data or data analysis in the final results.

We conducted the searches between September and October 2018 using the Digital Library of the University of Ljubljana portal, which provides access to databases of the most important publishers, including ScienceDirect, Web of Science, Scopus, CINAHL and PubMed. The following search terms were used in different combinations: spirituality, religiosity, depression, treatment, therapy, intervention, quality of life, life satisfaction. We included the latter two terms as they were considered potential outcome measures.

A total of 1474 publications were found among all journals listed in the databases. Based on the review of the titles and (if there was ambiguity) abstracts, we chose 31 articles for consideration. Scrutiny of those papers’ abstracts indicated that very few met the specific inclusion criteria for the study; that is, most papers did not examine spirituality as a treatment method for depression. Typically, we excluded papers for only mentioning the key variables of interest to the current study in a very general sense, for example, mentioning spirituality as a protective factor in patients with depression without exploring spirituality as an intervention method. We also excluded papers that studied people who had other health conditions listed as their primary diagnosis (for example, heart failure or cancer) where depression was just one of the variables that were observed in their recovery process. Furthermore, we were not interested in studies that explored different mindfulness techniques as those are not considered spiritual practices per se and are not necessarily linked to spirituality and personal growth [25].

Seven articles met all our inclusion criteria and were read in full. Moreover, we searched those articles’ bibliography and search engines Google and Google Scholar for articles of interest to our review. In this way, we additionally located five articles. However, following scrutiny of the five studies and a discussion between the authors, two were not included in the final review due to poor study design and lack of research rigor. Figure 1 schematically represents the search strategy and outcomes.

Fig. 1
figure 1

Systematic search strategy and outcomes

Full size image

Results

The final number of articles included in this literature review was 10. Nine articles were quantitative (seven of which were randomized control trials), and one was a qualitative study. The included articles are briefly presented in Table 1.

Table 1 Studies that included spirituality-based interventions for depression treatment
Full size table

Elements of Spirituality-Based Treatments that Have a Therapeutic Value

All articles included in the analysis described the elements of spirituality that were emphasized during the treatment process. There was some overlap between the spiritual concepts, and some themes were repeatedly mentioned, for example, gratitude, forgiveness, self-acceptance, and connectedness. Although some of the interventions stressed their non-denominational status to ensure compatibility with the participants’ beliefs, others drew on specific religious traditions and included techniques such as praying. Table 2 gives an overview of the elements of spirituality that were used in each intervention with people with depression.

Table 2 Elements of a spirituality-based treatment used in each study
Full size table

How to Include Spirituality in the Treatment of Patients with Depression

The spiritual treatment interventions aimed to achieve one or more of the following goals: (a) help patients express and affirm their spiritual identity; (b) assess the impact of religious and spiritual beliefs on the patient’s life, thoughts, and behaviors; (c)) help the patient use religious and spiritual resources to heal, cope with the situation, grow, and connect with others; (d) help the patient resolve spiritual concerns and doubts. Table 3 briefly describes how each spirituality-based method was delivered.

Table 3 Mode of delivery and a brief description of each spirituality-based intervention used in the study
Full size table

Spirituality was included in the treatment process in ways that respected the clients’ background and preferences. Seven of the studies involved no personal contact and relied on digital communications and distance learning. All interventions, however, stressed active participation rather than passive observation. Furthermore, great care was usually taken not to label the program in a way that would dissuade a person from using it. Thus, more neutral terms were used to present the program to potential participants. For instance, in a study by Rickhi et al. [34] a neutral recruitment slogan was used (“Feeling Down? A non-drug approach to treat depression”) in order to attract people with different views and beliefs.

Discussion

Our literature review aimed to provide a systematic overview of existing research examining the use of spirituality as a treatment method for depression. We identified some of the elements of spirituality-based treatments that have been studied in the literature together with strategies that were used to incorporate those methods into the treatment process.

Several mental health professionals have previously acknowledged the benefits of including spirituality in mental health interventions [35]. Most articles included in the review described the use of spirituality in the context of psychotherapy. The goal of psychotherapy is insight and growth; therefore, spirituality is usually compatible with most psychotherapy traditions [31]. Six of the studied interventions built on cognitive behavioral therapy (CBT). Most of the authors considered the similarities between spirituality and CBT, focusing on comparable concepts, such as gratefulness, forgiveness, and altruism [21, 28, 34]. Articles included in the review often directly or indirectly suggested that the connection between a scientific approach and a more spiritual/religious approach was paramount to the success of the overall treatment. One study described how the spirituality teaching program cultivated a frame of reference that accommodated and motivated cognitive and behavioral changes [28]. It appears that spirituality-based programs aim to provide a holistic approach that honors all aspects of a person’s life, therefore, offering an additional perspective within a traditional psychotherapy intervention for depression.

Some of the studies considered the patients’ pre-intervention religiosity (high or low religiosity/spirituality) and looked at the effect it had on the success of the intervention. Interventions were generally more successful with those who considered themselves religious/spiritual prior to the intervention. However, some studies (e.g., [3]) showed that the less religious participants responded well to the spirituality-based treatment, and their well-being and spiritual awareness increased afterward. Therefore, clinicians might consider offering elements of spirituality to both religious and non-religious patients in their treatment process.

Studies by Koenig et al. [21, 22]; Pearce et al. [29] and Ramos et al. [33] showed that if clinicians utilized the patients’ religious beliefs in therapy, this did not diminish the effect of standard CBT. Moreover, religious CBT was not inferior to standard CBT. It could, in fact, be superior when treating religious patients. The authors often expressed the notion that acknowledging a person’s belief system, values, and deep convictions could have a healing potential. For instance, several individuals in the study conducted by Moritz et al. [28], who had undergone secular psychological therapy or counseling, reported that spirituality practices were more helpful than conventional therapies. A sense of well-being was related to a newly found sense of spiritual connection, spiritual meaning, and enhanced spiritual awareness.

The affiliations and identities of the people who facilitated spirituality in the treatment process differed considerably, ranging from laypersons and chaplains to trained psychotherapists. However, all articles mentioned that the facilitators received professional training before the intervention, suggesting that they were aware of their responsibilities concerning the patients they treated. For instance, it was the therapist’s role to determine whether religious issues and concerns were grounded on dysfunctional cognition, and, if necessary, direct the client to more healthy ways of thinking based on religious teachings in their particular tradition [21]. In addition, the studies noted some of the precautions of spirituality-based interventions. For example, we should not impose spirituality on people. Their spiritual needs and traditions need to be considered, including the lack of such needs [31]. It can also be dangerous if some patients start feeling so confident about the spiritual treatment that they abandon pharmacological therapy. The role of the professional is to guide in such cases [26, 31].

While some techniques described in the articles were explicitly non-denominational so that persons of different religious, cultural, and personal backgrounds could accept them, others were adapted to the religious affiliation of the recipient thus making them less universal. Some focused more on the relationship with God (e.g., praying), while others explored the psychological dimensions within the person, such as a sense of self, a sense of meaning and connectedness, gratitude, and forgiveness. Rickhi et al. [35] observed that the use of the name spirituality resulted in some recruitment challenges and raised questions as to whether the program would challenge one’s existing belief systems or religious values. Therefore, a significant amount of time was often dedicated responding to concerns and explaining the neutral orientation of the programs. This aspect should be considered when designing and presenting a spirituality-based program as well as when naming it not to deter potential participants.

Out of the elements of spirituality that were used in the interventions, gratitude, in particular, has received a lot of scientific support as a potential intervention in mental health. Jung and Han [18] previously found that a gratitude promotion program could be an effective clinical intervention for reducing depression and enhancing the quality of life in patients with schizophrenia. Another study showed that gratitude could ameliorate depressive symptoms [6]. Disabato et al. [15] also suggested that gratitude and meaning in life can lead to increased positive life events and, in turn, decrease depression. Our review identified gratefulness as a potential element of spiritual interventions in mental health. Gratefulness could, therefore, be considered when developing evidence-based interventions that are based on spirituality.

The studies included in the review also suggested a growing trend toward e-mental health. Although e-mental health is becoming an essential strategy in mental health services for depression [8], it is somewhat surprising that spirituality-related concepts appeared to be so easily communicated without personal contact and guidance. Technology is ubiquitous and makes services accessible to everyone, which can make technology-based interventions more attractive, especially to the younger generations. According to the review, digital, spirituality-based interventions might be a viable option in the treatment of depression and should probably be considered in future mental health care.

According to the review, another area that might require more attention in the future is spirituality for older people who are approaching death [3]. Expressing their feelings about life satisfaction and the “unfinished business” they might want to resolve in the remainder of their life, could benefit older people. This type of spiritual care requires specific support and skills so that people can get reassurance about their past actions and reach a deeper understanding and a sense of peace and reconciliation.

The studies included in this review had several limitations. For instance, they mainly focused on Christian clients and those who were at least somewhat religious or spiritual, which restricts the generalizability of findings to other religious group and non-religious people. Also, many of the studies were pilot studies and the samples were relatively small. Participants were often volunteers who self-recruited, which could suggest a potential selection bias, meaning that the studies included people who had a favorable attitude toward spirituality, and were open to new methods of treatment. On the other hand, a high number of studies were randomized control trials, suggesting a drive for methodological rigor.

Conclusions

The literature review suggests that spirituality-based treatments could be a viable option in the treatment of depression, particularly for patients who consider themselves religious or spiritual. Spirituality needs to be delivered professionally by facilitators who have received appropriate training to assess and guide the patient. Some aspects of spirituality have demonstrated the potential to have a healing effect, including gratefulness, forgiveness, connectedness, compassion, and self-acceptance, as they stimulate personal growth and insight. Therefore, those elements can be incorporated into different psychotherapy traditions. Digital, spiritualty-based interventions appear to be an emerging trend and should be considered as an opportunity to make mental health services available to more people.