Treatment-resistant or untreatable?

Treatment-resistant bipolar depression: concepts and challenges for novel interventions

Treatment-resistant bipolar depression (TRBD) has been reported in about one-quarter of patients with bipolar disorders, and few interventions have shown clear and established effectiveness. We conducted a narrative review of the published medical literature to identify papers discussing treatment-resistant depression concepts and novel interventions for bipolar depression that focus on TRBD. We searched for potentially relevant English-language articles published in the last decade. Selected articles (based on the title and abstract) were retrieved for a more detailed evaluation. A number of promising new interventions, both pharmacological and non-pharmacological, are being investigated for TRBD treatment, including ketamine, lurasidone, D-cycloserine, pioglitazone, N-acetylcysteine, angiotensin-converting enzyme inhibitors, angiotensin II type 1 receptor blockers, cyclooxygenase 2 inhibitors, magnetic seizure therapy, intermittent theta-burst stimulation, deep transcranial magnetic stimulation, vagus nerve stimulation therapy, and deep brain stimulation. Although there is no consensus about the concept of TRBD, better clarification of the neurobiology associated with treatment non-response could help identify novel strategies. More research is warranted, mainly focusing on personalizing current treatments to optimize response and remission rates.

Treatment-resistant depression: a survey of practice habits of Canadian psychiatrists

Treatment-resistant depression is a fascinating yet poorly defined condition. The various management strategies in use are a source of controversy. The objective of this survey was to determine how Canadian psychiatrists treat patients with "intractable depression." This information may be used to plan future research into the management of treatment-resistant depression. It may also provide information about the practices of Canadian psychiatrists and help direct residency training. Confidential questionnaires were mailed to all psychiatrists residing in Canada registered with the Canadian Psychiatric Association. Respondents indicated that 12.4% of their depressed patients were "resistant to treatment." Respondents were asked to rank a list of treatment choices in the order they would use them to treat patients with treatment-resistant depression. Ninety-five point eight percent of respondents used tricyclics as the first treatment of choice. Almost equal portions of respondents chose a second tricyclic, a monoamine oxidase inhibitor (MAOI) or a combination of lithium and tricyclics as their treatment of second choice.

Chronic depression

Defining chronic depression as persistent symptoms for 2 or more years, a prevalence of chronic depression of 12-15% is found in the literature. A four-part classification of chronic depression is proposed: Chronic Primary Major Depression; Chronic Secondary Major Depression; Characterological or Chronic Minor Depression (Dysthymic Disorder); and 'Double Depression'. The literature indicates several factors predicting chronicity in primary major depression: more at risk are female patients, particularly those with premorbid neurotic personality traits, individuals with unipolar disorders, and those with higher familial loading for such disorders. Other factors are the adequacy and appropriateness of the treatment given, and the length of illness episode prior to treatment being received. Larger studies with well-matched controls are needed.

The Newcastle Chronic Depression Study. Patient characteristics and factors associated with chronicity

Chronic depression is defined as "symptomatic non-recovery for a period of 2 or more years". Chronic primary major depressives (n = 24) were compared retrospectively with a control group of primary major depressives (n = 20) who had recovered from their illness episode within 2 years. The former had a significantly higher familial loading for affective disorder and showed an increased incidence of independent undesirable life events during the 6 months prior to and 2 years after the onset of their illness. Female chronic depressives also had a significantly greater number of previous illness episodes and a more frequent history of thyroid dysfunction. Personality as measured on the EPO, psychiatric problems arising as secondary complications of the depressive illness, and developmental object loss did not differentiate chronic from non-chronic depressives.