Depression and Anxiety
Clinical Overview of Depressive Disorders
There are several types of depression: major depressive disorder (MDD), that can occur in unipolar or bipolar mood disorders (formerly known as manic depression and characterized by both depressive and manic episodes), atypical depression (characterized notably by increased sleep and appetite) and dysthymic disorder (mild depression persisting for two years or more).
Genetic, environmental and psychological factors are thought to interact to trigger a depressive episode. People who have a first-degree relative with a mood disorder are two to four times more likely to develop depression sometime in their lives.
Current antidepressant therapies fall into several classes of drugs that act mainly on serotonergic, noradrenergic or dopaminergic systems, such as the tricyclic antidepressants, the selective serotonin uptake inhibitors, mixed serotonin/noradrenergic uptake inhibitors, and monoamine oxidase inhibitors.
Clinical Overview of Anxiety Disorders
Common anxiety disorders include generalized anxiety disorder (GAD), panic disorder, obsessive-compulsive disorder (OCD), post-traumatic stress disorder (PTSD), social phobia (or social anxiety disorder) and specific phobias.
The causes of anxiety disorders are likely an interplay of genetic, environmental, and psychological factors. Anxiety disorders are typically treated with antidepressants or benzodiazepines. Depression often co-occurs with anxiety disorders and, in many cases, progresses to Depressive Disorders.
Major Clinical Challenges to Current Treatment of Anxiety and Depression
• With current treatments, there is a latency period of weeks to months before the treatment reaches its maximum clinical effect (therapeutic lag).
• Side effects, such as nervousness, agitation, insomnia, fatigue, sexual dysfunction and weight gain, decrease compliance and frequently result in discontinuation of drug use.
• Only 40 percent to 60 percent of people achieve a response to currently available therapeutics and 30 to 40 percent achieve a remission of symptoms.
• Relapses are frequent and occur both during maintenance treatment with existing medications as well as following drug discontinuation.