Incidental treatment effects of CBT on suicidal ideation and hopelessness

Abstract

Background

Depression and alcohol misuse are among the most prevalent diagnoses in suicide fatalities. The risk posed by these disorders is exacerbated when they co-occur. Limited research has evaluated the effectiveness of common depression and alcohol treatments for the reduction of suicide vulnerability in individuals experiencing comorbidity.

Methods

Participants with depressive symptoms and hazardous alcohol use were selected from two randomised controlled trials. They had received either a brief (1 session) intervention, or depression-focused cognitive behaviour therapy (CBT), alcohol-focused CBT, therapist-delivered integrated CBT, computer-delivered integrated CBT or person-centred therapy (PCT) over a 10-week period. Suicidal ideation, hopelessness, depression severity and alcohol consumption were assessed at baseline and 12-month follow-up.

Results

Three hundred three participants were assessed at baseline and 12 months. Both suicidal ideation and hopelessness were associated with higher severity of depressive symptoms, but not with alcohol consumption. Suicidal ideation did not improve significantly at follow-up, with no differences between treatment conditions. Improvements in hopelessness differed between treatment conditions; hopelessness improved more in the CBT conditions compared to PCT and in single-focused CBT compared to integrated CBT.

Limitations

Low retention rates may have impacted on the reliability of our findings. Combining data from two studies may have resulted in heterogeneity of samples between conditions.

Conclusions

CBT appears to be associated with reductions in hopelessness in people with co-occurring depression and alcohol misuse, even when it is not the focus of treatment. Less consistent results were observed for suicidal ideation. Establishing specific procedures or therapeutic content for clinicians to monitor these outcomes may result in better management of individuals with higher vulnerability for suicide.

Introduction

Suicide is an issue of major concern among clinical populations, with approximately 90% of suicide victims experiencing a psychiatric condition at their time of death (Mann et al., 2005). Particular attention has been paid to the impact of depression and alcohol abuse on suicidality, both of which pose an independent suicide risk (You et al., 2011). These conditions frequently co-occur (Teesson et al., 2009), particularly in clinical settings (Davis et al., 2006, Lubman et al., 2007), further exacerbating the vulnerability for suicidal thoughts and behaviours (Bartels et al., 2002, Cornelius et al., 1995, Sher et al., 2005, Sher et al., 2008, Schneider, 2009).

In clinical populations, hopelessness and suicidal ideation have been ranked as the first and second most important suicide risk factors respectively, and are perceived to be reliable indicators of an individual's future potential for suicide (Truant et al., 1991). In clinical settings, elevated hopelessness has been reliably shown to be present in over 90% of individuals who eventually die by suicide, with these findings replicated in both inpatients and outpatients (Beck et al., 1985, Beck et al., 1990). Similarly, significant levels of suicidal ideation are observed in 80% of psychiatric outpatients who take their own life (Beck et al., 1999). Both symptoms are reported frequently in individuals with a diagnosis of depression, and may be more severe among individuals with comorbid alcohol misuse (Sher et al., 2005). However, the specific relationship between suicide vulnerability (i.e. markers of suicidality such as suicidal ideation and hopelessness) and comorbidity remains unclear. While suicidal ideation is related to the severity of depression (Gensichen et al., 2010), alcohol use disorders in themselves do not predict thoughts of suicide (Kelly et al., 2001). This is despite alcohol misuse being associated with significantly increased severity of depressive symptoms, and alcohol misuse and depression likely exerting a synergistic impact on suicide risk, with co-occurrence of these disorders contributing to greater risk than either occurring in isolation (Fergusson et al., 2009). For example, Effinger and Stewart (2012) have recently shown that, among adolescents in the USA with either a depressive or substance use disorder, the presence of even sub-threshold symptoms of the other disorder significantly increases risk of suicide. Other research shows no direct correlation between hopelessness and clinical indications of either depressive symptoms or alcohol misuse (Whisman et al., 1995). The implications of this in a clinical setting are considerable: while individuals with depression and alcohol misuse are a high-risk group for suicidal behaviours, these findings suggest that targeting these primary conditions alone may be insufficient to reduce this vulnerability.

Cognitive behaviour therapy (CBT) is among the most common and effective treatments for both depression and alcohol use problems, and can be used to address these conditions either independently or in an integrated format (Kay-Lambkin et al., 2011, Kay-Lambkin et al., 2009, Baker et al., 2010). Recent evidence has also been found to support the use of computer-delivered CBT, which is equally effective in reducing depressive symptoms and substance use, while increasing the accessibility of treatment (Kay-Lambkin et al., 2011). It has been suggested that cognitive therapy, which focuses on reducing dysfunctional attitudes in depression, may be uniquely appropriate for addressing both hopelessness and suicidal ideation (Rush et al., 1982, Raj et al., 2001). While CBT generally targets a client's “primary” diagnosis, integrated treatment for comorbid depression and alcohol misuse is emerging as an important approach in the context of comorbid disorders. Evidence suggests that combining treatments may lead to a greater decrease in symptoms of both depression and alcohol use than observed through single-focused treatments for either condition alone (Baker et al., 2010). It has also been suggested that for people with comorbid conditions, integrated treatments may be necessary to reduce suicide vulnerability (Lecrubier, 2001). However, to our knowledge there is no research exploring integrated treatments, either therapist- or computer-delivered, that tests this suggestion, and includes suicide vulnerability as an outcome.

While CBT may be an ideal approach to decrease suicide vulnerability among individuals with depression and alcohol misuse comorbidity, its effectiveness has rarely been tested in this context. Although some research has found CBT to be effective at targeting both suicidal ideation and hopelessness in clinical populations (Rush et al., 1982, Raj et al., 2001), conflicting results indicate cognitive therapy is no more effective than usual care in the immediate or long-term, with only marginal effects witnessed for hopelessness at 6-months (Brown et al., 2005). However, existing studies have either been inadequately powered, or only have explored interventions concerned with short-term treatment outcomes (e.g. Rush et al., 1982, Stewart et al., 2009), with longer-term effects not reported. The validation of existing findings using a larger sample and a longer-term longitudinal design may help clarify the effectiveness of CBT in addressing suicide vulnerability. Additionally, previous studies have primarily explored cognitive therapy that specifically focuses on the reduction of suicidal thoughts and behaviours. While this is valuable knowledge, it is also important to explore the effects of therapies that do not directly target suicidality. Standard practice in therapy is to treat the primary condition with which the client presents, and while suicide risk may be noted, it is not necessarily highlighted as a focus of concern (Oquendo et al., 2008). It is therefore important to evaluate the typical approach of treating the conditions of depression and alcohol abuse to determine the independent effects of this non-targeted treatment on suicide vulnerability.

The primary aims of the present analysis were: (1) to explore whether CBT, targeting depression and alcohol misuse, is associated with clinically significant reductions in indicators of suicide vulnerability (suicidal ideation and hopelessness) over a 12-month period in a large sample with sufficient power to detect expected clinical effects; (2) to investigate whether the method of treatment delivery (i.e. single-focused compared to integrated treatment, therapist-delivered versus computer-delivered treatment) is associated with differential effects on the course of suicide vulnerability; and (3) to determine whether changes in suicide vulnerability indicators occur in accordance with change in depression and/or alcohol use, or independently from these conditions. We hypothesised that CBT will effectively reduce suicide vulnerability when compared to a control treatment of supportive counselling, and that integrated treatment will lead to a greater reduction in suicide vulnerability in a sample with comorbid conditions. Based on previous research, we predicted no differences between therapist-delivered and computer-delivered treatments (Kay-Lambkin et al., 2011), or between brief and 10-session treatments (Baker et al., 2010).