The effect of cognitive behavior therapy on anxiety and depression during COVID-19 pandemic: a systematic review and meta-analysis

The worldwide outbreak of coronavirus pandemic since 2019 became a very serious crisis for all people and posed many challenges for world health community as well as research and medical committees [1]. Presently, people from all age groups including children to adults and people with any health background are at risk of coronavirus infection, so that by August 25, 2021, more than 214,000,000 people in the world were infected with the virus of whom more than 4,470,000 people lost their lives [2].

Although a lot of attention is paid to coronavirus pandemic, and its news and information are broadcasted moment by moment, the attention is just paid to the pathogenic aspect of coronavirus, while its psychological effects on society are neglected most of the time [3]. Each traumatic event may reduce people’s sense of security and affect their mental health negatively. Being exposed to coronavirus news and unanswered questions about when the pandemic ends and what its treatments are, along with decreased social relations and widespread quarantines all have negative effects on people’s mental health [3, 4]. Moreover, decline of some people’s income because of widespread lockdowns disrupts families’ well-being and affects their quality of life and consequently their mental health negatively [5]. Extremely rapid transmission and high mortality rate of this disease lead to psychological problems or worsen the former problems in people [6]. Some symptoms such as anxiety, depression, fear, stress, and insomnia are very common during coronavirus pandemic [3].

Depression is a common disorder that presently affects nearly 120 million people all over the world and its prevalence rate is between 10% and 15% in a lifetime according to epidemiological surveys [7]. Anxiety is also another common mental disorder. Mental disorders, according to WHO, account for 30% of nonfatal illnesses and it is estimated that 1 in 5 persons are exposed to anxiety and depression in critical conditions [8]. A study conducted in China showed that prevalence of depression and anxiety increased significantly among general population during COVID-19 crisis [9].

Since COVID-19 pandemic has a lot of implications for personal, social, and emotional health; emotional and social needs of people during this period should receive enough attention from providers of these services and health policy makers, in addition to medical services [10]. Cognitive behavior therapy (CBT) is a psychological therapeutic approach that is extensively used both as a prevention and a treatment method for both medical staff and general population [11]. CBT is a set of methods including cognitive restructuring and behavioral change that helps people control their stress, change their negative behavior and attitudes and, likewise, reduces the symptoms of distress and mental health problems [12].

CBT is an intervention that improves the coping skills in anxiety. This intervention help an individual how respond to stressful events in their life [13]. For mild to moderate depression, CBT even competes with antidepressant medications and a combination of CBT and antidepressant medications increases the effectiveness of treatment. Among all the psychotherapies, CBT is considered the first line of treatment for depression [14]. Thus, effectiveness and efficiency of this treatment are approved for both anxiety and depression.

Considering the increasing cases of psychological problems including anxiety and depression during the recent pandemic and the existence of various psychological therapies, we decided to meta-analysis and systematically review the effectiveness of CBT on anxiety and depression during this period.

A total of 2015 articles were obtained from the search in different databases of which 1987 articles were excluded due to duplicates or the irrelevancy of their titles or after reviewing their abstracts. Of 28 remaining articles, 14 of the articles did not enter the systematic review due to the following reasons: Mohammadi et al. [15] and Norred et al. [16] articles were excluded from the study because of its editorial type. Hosseinzade et al. [17] article did not include to the study, because it was a study protocol. Kalvin et al. study [18] was a commentary study. Likewise, Mahoney et al. study [19], Zhang et al. study [20], Araghi et al. study [21] and Uysal et al. study [22], Green et al. study [23] were excluded from the study due to lack of the control group. Johnco et al. study [24] and Sharrock et al. study [25] did not enter the study, because the studies were conducted previously and the follow-up was conducted again in the coronavirus period. Fadhli et al. study [26] was excluded, since the mean and standard deviation of results before and after the intervention were reported as a single value together and the effects of the intervention were not properly stated. Likewise, Perri et al. study [27] and Hamed et al. study [28] were excluded from the study, because its control group had received another type of intervention. Of the 14 remaining articles, one article was not retrieved, because the full text of Barve et. al [29] study was not available, we emailed the authors but we did not receive any response; so this article was not included in the present study. In addition, two of the articles including Oehler et al. study [30] due to lack of anxiety scores before and after the intervention and LV et al. study [31] because of presenting insufficient data were excluded from the study. Finally, 11 articles were entered into the study (Fig. 1).

The risks of biases of the entered studies are presented in Table 2. Most of the studies did not provide sufficient data on how randomization was done and so are placed at unclear risk level; likewise, most of the studies are put at low risk level regarding allocation concealment bias. All of the studies are high risk in terms of performance bias. All studies except one [32] are at high-risk level in terms of detection bias. Moreover, all studies are low risk in terms of reporting bias and attrition bias (Figs. 2 and 3).

According to most of the studies, COVID-19 pandemic has a negative impact on individual mental health so different psychological approaches should have been used to improve society’s well-being. CBT is one of the effective approaches for psychological disorders. In the present study, the effects of CBT on people’s depression and anxiety in COVID-19 pandemic period were analyzed. Based on the overall results of meta-analysis, CBT had a significant effect on reducing anxiety and depression. Since we did not find systematic review studies on the effects of CBT on anxiety and depression in coronavirus period, we reviewed similar studies. No study was found that examined both outcomes so we have reviewed outcomes separately. There were some studies that evaluated the effect of CBT on the anxiety.

Hall et al. [42] evaluated the effects of CBT on the anxiety disorder. Meta-analysis results in the study were similar to the present study and showed that CBT was significantly effective on reducing anxiety in the intervention group. Unlike the present study, in the Hall et al. study, control groups have received different interventions, such as supportive therapy, acceptance and commitment therapy, discussion group and etc. In a systematic review and meta-analysis, Sigurvinsdóttir et al. [43] studied the effects of CBT on anxiety. Meta-analysis results showed that CBT was significantly effective. Sigurvinsdóttir study was conducted just on children and adolescents, and so its results could not be generalized to other age groups but the present study has no age limitation in inclusion criteria.

There are a number of articles that evaluated the effect of CBT on depression. In a systematic review, Lopez-Lopez et al. [44] investigated the effects of CBT on depression. This study conducted just on adults above 18. In the present study, we have no age limitation. In a systematic review and meta-analysis, Santoft et al. [45] studied the effect of CBT on depression. This study has reviewed more articles than the present study (34 articles) and control groups have received different interventions, such as placebo pill, psychotherapy and etc. The results of Santoft et al. study similar to the results of the present study showed that CBT significantly reduced symptoms of depression in the intervention group. All of these studies were conducted before COVID-19 pandemic.

CBT is a therapeutic approach that is suggested for the treatment of depression and anxiety by Aaron beck. CBT helps the patients change their thoughts and through which leads to better feelings in them [46]. Since negative thoughts have a detrimental influence on developing emotional disorders such as anxiety and depression, CBT alleviates anxiety and depression symptoms through recognizing, challenging, and changing negative thoughts and replacing them with logical thoughts [47]. Moreover, CBT improves many mental health disorders such as anxiety and depression through developing capabilities necessary for coping with everyday life events [48], and since many studies approve that CBT is one of the valid therapeutic methods, it is extensively used. Most of the studies detected changes in the brain (such as prefrontal hyperactivity) during psychological disorders, such as anxiety and depression. Findings of studies showed that the abnormal hyperactivities of the prefrontal decrease following treatment. In addition, results showed that CBT can enhance the prefrontal control structures [49, 50]. In some of the studies, researchers used internet-based CBT instead of face to face CBT due to COVID-19 pandemic.

The results of the subgroup meta-analysis showed that ICBT (internet-based CBT) is effective in reducing depression and anxiety. In the Farrer et al. study [51], ICBT was effective in reducing depression, although they used weekly telephone tracking too. In Herman et al. study [52], ICBT was effective in reducing anxiety. They followed up the participants for 5 years. The results of Etzelmueller et al. [53] and Lau et al. [54] studies were similar to the present study too and ICBT was effective in reducing depression and anxiety. However, Etzelmueller et al. study has reviewed more articles than the present study (19 articles) and they included adults and older adolescents in their study. In the present study, we have no age limit. In addition, the participants of the Lau et al. study were postpartum women. All of these studies were conducted before COVID-19 pandemic.

This systematic review and meta-analysis has a number of weaknesses and strengths. One of the limitations was the small sample size of the included studies. In addition, we had just 11 studies which also limited our sub-group analyses. The other limitations of the present study were different study designs, participant’s ages and outcome measures. In addition, the most of the included studies did not clearly stated their methods of randomization and so were placed in unclear risk level in terms of randomization bias, just one study [39] was low risk in this regard. In none of the studies blinding was performed, however, in just one study [31], analyzer’s blinding was done. Of other weaknesses of the included studies was their different inclusion criteria, for instance, some of the studies were conducted on people infected with coronavirus, some on people having a history of depression and anxiety, and some on people not infected with coronavirus. Likewise, in most of the studies duration of follow-up was not stated. In most of the studies, because of coronavirus pandemic and the necessity of quarantine and observing social distance, CBT counseling sessions were performed online and via internet that is one of the weaknesses of these studies, because there was no possibility of face to face meetings between counselors and clients; however, this was the best decision in the pandemic period and provided people with the opportunity to benefit from counseling and the results also showed the effectiveness of the method.

One the strengths of the present study is that all of the included studies are at low-risk level in terms of reporting bias and attrition bias. Likewise, in the present systematic review, all age groups regardless of their sex entered the study, so the results are generalizable to all age groups and both sexes. Of other strengths of this study, we can refer to subgroup analysis.

Meta-analysis shows that CBT is significantly effective on reducing depression and anxiety scores in COVID-19 pandemic period. Therefore, extensive use of this method during coronavirus pandemic and other similar pandemics is recommended. It is suggested that the effectiveness of other psychological approaches on the problems developed during the pandemic to be analyzed in other studies. Moreover, since the need for counseling and psychological interventions is inevitable due to psychological and mental disorders people experience during different kinds of crises such as natural or social crises or pandemics etc., it is recommended that governments and communities put paying enough attention to these methods on their agenda.