Depression has been cited as the most prevalent of the Axis I disorders affecting upward of 16% of American adults in their lifetimes (Kessler et al., 2005). The literature on effective treatments for depression is substantial, however the follow-up literature that speaks to what happens after treatment ends is much smaller. This thesis describes two studies. The first is an overview of reviews of post-treatment outcomes for adults treated for major depressive disorder (MDD). The second is a narrative systematic review of studies of long-term (at least 12 months) post-treatment outcomes after the completion of treatment for major depressive disorder (MDD). These studies synthesize the available evidence concerning post-treatment outcomes and discuss the limitations of these data. Relapse is a significant issue for many people who respond to treatment with upwards of 50% of people relapsing within a year of the end of treatment, depending on the type of treatment. Some treatments have significant relapse prevention effects, including continued medication treatment, acute and continuation phase CBT, and variations of CBT designed specifically for addressing residual symptoms after acute treatment or specifically aimed at relapse prevention. Given that the risk of relapse after treatment is significant, it should be discussed during acute treatment, as should approaches to reducing the risk of relapse. Recommendations for future research are discussed. Within the overview of reviews, there was considerable consistency across reviews which aided in the formulation of practical recommendations for clinicians and for patients. Examples include provision of education about the probability of relapse and planning for relapse prevention during acute phase treatment. Engaging in continuation and maintenance treatments that are aimed at reducing relapse, and whenever possible, continuing treatment until patients are considered to be in recovery, and not just for a certain period of time, or until the point of remission of symptoms are also recommended to reduce rates of relapse.

Depression has been cited as the most prevalent of the Axis I disorders affecting upward of 16% of American adults in their lifetimes (Kessler et al., 2005). The literature on effective treatments for depression is substantial, however the follow-up literature that speaks to what happens after treatment ends is much smaller. This thesis describes two studies. The first is an overview of reviews of post-treatment outcomes for adults treated for major depressive disorder (MDD). The second is a narrative systematic review of studies of long-term (at least 12 months) post-treatment outcomes after the completion of treatment for major depressive disorder (MDD). These studies synthesize the available evidence concerning post-treatment outcomes and discuss the limitations of these data. Relapse is a significant issue for many people who respond to treatment with upwards of 50% of people relapsing within a year of the end of treatment, depending on the type of treatment. Some treatments have significant relapse prevention effects, including continued medication treatment, acute and continuation phase CBT, and variations of CBT designed specifically for addressing residual symptoms after acute treatment or specifically aimed at relapse prevention. Given that the risk of relapse after treatment is significant, it should be discussed during acute treatment, as should approaches to reducing the risk of relapse. Recommendations for future research are discussed. Within the overview of reviews, there was considerable consistency across reviews which aided in the formulation of practical recommendations for clinicians and for patients. Examples include provision of education about the probability of relapse and planning for relapse prevention during acute phase treatment. Engaging in continuation and maintenance treatments that are aimed at reducing relapse, and whenever possible, continuing treatment until patients are considered to be in recovery, and not just for a certain period of time, or until the point of remission of symptoms are also recommended to reduce rates of relapse.