Treatment-resistant depression (TRD) is associated with a poor quality of life and
high economic burden. This observational retrospective epidemiological study aimed
to estimate the proportion of patients with TRD within a cohort of patients with major
depressive disorder (MDD) in Hungary and examine the mortality and comorbidities of
patients with and without TRD.This study included patients with MDD who experienced
onset of a new depressive episode between 01 January 2009 and 31 August 2015, using
data from a nationwide, longitudinal database.Overall, 99,531 patients were included
in the MDD cohort, of which 8,268 (8.3%) also met the criteria for TRD. The overall
survival of non-TRD patients was longer than in TRD patients; the risk of mortality
for TRD patients was significantly higher than of non-TRD patients (HR [CI] 1.381
[1.212-1.571]; p<0.001). Patients with TRD had a significantly higher probability
of having "Neurotic, stress-related and somatoform disordersˮ, autoimmune conditions,
cardio- or cerebrovascular diseases, thyroid gland diseases and self-harming behaviour
not resulting in death than non-TRD patients (for all comparisons, p values were less
than 0.005).To our best knowledge, this is the first study to assess the frequency
of TRD in Hungary. In a cohort of Hungarian MDD patients, we have found that the proportion
of TRD (~8.3%) is comparable to those reported in previous studies with similar methodology
from other countries. The majority of our other main findings (e.g. more frequent
self-harming behaviour, increased risk of "Neurotic, stress-related and somatoform
disordersˮ and higher overall mortality in TRD subjects) are also in line with previous
results from other countries. Taking the substantial proportion of patients with TRD
into consideration, a more comprehensive and targeted treatment strategy would be
required for these individuals.
