Classes of depression, anxiety, and functioning in acute coronary syndrome patients.

Depression and anxiety are highly prevalent disorders in patients after an acute coronary syndrome (ACS).1-7 Depression and anxiety co-occur, appear to inhibit recovery, and have a negative impact on social functioning and capacity to perform activities of daily living in patients who develop an ACS.3,4,6,8-14 Even though these conditions are prevalent in patients with an ACS, and are associated with poorer quality of life, these disorders are not fully recognized and adequately treated in clinical settings. Moreover, the effectiveness of intervention programs designed to increase quality and length of life after an ACS still needs to be evaluated across multiple domains.2,6,11 In addition, a patient’s level of functioning may interact with his or her depression and/or anxiety to determine an intervention’s effectiveness.2,6,11 Assessing the effectiveness of an intervention program across multiple domains, namely by considering the remission of symptoms of depression, anxiety, and impaired functioning simultaneously over time, may provide a more accurate assessment of its overall impact on health. Other investigators such as the Enhanced Recovery in Coronary Heart Disease (ENRICHD) group have investigated the effectiveness of cognitive behavioral therapy (CBT) in reducing depressive symptoms as well as improving functioning in patients after an ACS.1,12 However, to our knowledge, there are no reports on the effect of CBT where the symptoms of depression, anxiety, and impaired functioning are considered simultaneously over time. The current study is designed to supplement the results of previously reported clinical trials primarily by considering the effect of CBT treatment on multiple outcomes simultaneously. This approach provides a way to examine the impact of treatment on patient well-being more holistically. That is, this approach takes a developmental perspective where multiple aspects of patient well-being are modeled simultaneously and dynamically. The current study has 3 primary objectives. The first is to use latent class analysis (LCA) and latent transition analysis (LTA) to identify and describe subgroups of patients characterized by similar patterns of depression, anxiety, and functional impairment as well as to describe change over time in subgroup membership. The second is to use these same methodologies to determine whether patients receiving CBT report improvement in the 3 domains simultaneously compared to the control group. The third is to examine whether sex and age predict remission of depression, anxiety, and functional impairment. Generalized estimating equations are used to address the third objective.