The relationships between socio-demographic and clinical data and the bipolar spectrum features in treatment resistant patients. A pilot study

Objective: To asses the relationships between sociodemographic and clinical data and the bipolar spectrum features in treatment resistant patients. (A sub-analysis of data of the pilot study for the multi-center TRES-DEP (Treatment Resistant Depression) Project.

Methods: 50 drug-resistant 18-65 year old patients, fulfilling ICD-10 criteria for depressive episode or recurrent depressive disorder (F32, F33) were included in the study. Drug resistance was defined as non-response to two adequate antidepressant treatments. The main exclusion criteria were: > 18 scores in the 17-item Hamilton Depression Rating Scale, treatment with mood stabilizers, the diagnosis of: substance misuse, dementia, severe neurological or other somatic disease. The presence of bipolar spectrum was detected by the Mood Disorder Questionnaire (MDQ) and the Hypomania Checklist Scale (HCL).

Results: Statistically significant more drug-resistant patients fulfilling MDQ bipolar spectrum criteria (MDQ (+))comparing to patients without bipolar spectrum features by MDQ (MDQ(-)): 1) considered the last remission as partial or reported lack of remission (100% vs. 21%; p<0.05), 2) reported treatment non-adherence (41 vs. 18%, p=0.055). Moreover there were more suicidal attempts in MDQ(+) patients (0.86+/-1.28 vs. 0.25+/-0.59; p<0.05).

Conclusions: Results of the study suggest that the presence of bipolar spectrum may worsen the course and outcome of drug-resistant depression. A further multicenter study is needed.