Recurrent brief depression (RBD)

Recurrent Depressive Disorder is defined in ICD-10 as:

• the disorder meets the criteria for a mild, moderate or severe depressive episode
• the depressive episodes have occurred about once per month over the last year
• the individual episodes last less than 2 weeks (typically less than 2-3 days)
• the episodes do not occur solely in relation to the menstrual cycle

Recurrent Depressive Disorder (RBD) has exactly the same psychopathological cluster of symptoms as as in Major Depressive Disorder (MDD) but RBD can be only distinguished from MDD only by the duration criterion (episode duration <14 days) and the frequency criterion (approx. 1 episode/month). Therefore RBD cannot be viewed as a 'milder form' of depressive diorder. Note also that the the ICD-10 requires independence of the menstrual cycle and an observation period of 1 year.

• epidemiology - study evidence of a lifetime prevalence rates of pure RBD without mood disorder comorbidity of:
  • 12.5% - this is similar to pure major depressive disorder (MDD) without mood disorder comorbidity with a prevalence rate of 14.7%
  • gender distribution of RBD is distinct from MDD showing a balanced sex ratio in RBD (1:1.3) whereas there is a female excess in MDD (1:16.3)
  • a previous study stated the 1-year prevalence in the general population is about 5% and the lifetime prevalence 16% for RBD (2)
• recurrent brief depression may develop into major depression and vice versa in about the same percentage of cases (2)
  • RBD is associated with considerable suicidality and treatment-seeking and is comorbid with anxiety disorders
  • patients with combined major and recurrent brief depression are more severely affected, have a higher suicide attempt rate, and have an increased frequency of treatment-seeking than patients with only one condition
  • suicide attempts were reported to be less frequent in RBD (10.2%) without mood disorder comorbidity than in MDD (20.2%) in the Zurich study (2)

Management:

• optimal treatment regime for RBD is, at present, unclear
  • it has been suggested that (1) a prescription with modern antidepressants seems to be appropriate first-line treatment. Note though that longer response rates (weeks to a few months) than in MDD are characteristic for RBD since symptoms are occurring less frequently in comparison to major depressive episodes

Reference:

1. Pezawas L et al.Recurrent brief depression—past and future. Progress in Neuro-Psychopharmacology and Biological Psychiatry 2003; 27(1): 75-83.
2. J Clin Psychiatry. 1994 Apr;55 Suppl:3-9.