Background: A number of scales are used to estimate the severity of depression. However, differences between self-report and clinician rating, multi-dimensionality and different weighting of individual symptoms in summed scores may affect the validity of measurement. In this study we examined and integrated the psychometric properties of three commonly used rating scales.Method: The 17-item Hamilton Depression Rating Scale (HAMD-17), the Montgomery–Asberg Depression Rating Scale (MADRS) and the Beck Depression Inventory (BDI) were administered to 660 adult patients with unipolar depression in a multi-centre pharmacogenetic study. Item response theory (IRT) and factor analysis were used to evaluate their psychometric properties and estimate true depression severity, as well as to group items and derive factor scores.Results: The MADRS and the BDI provide internally consistent but mutually distinct estimates of depression severity. The HAMD-17 is not internally consistent and contains several items less suitable for out-patients. Factor analyses indicated a dominant depression factor. A model comprising three dimensions, namely ‘observed mood and anxiety’, ‘cognitive’ and ‘neurovegetative’, provided a more detailed description of depression severity.Conclusions: The MADRS and the BDI can be recommended as complementary measures of depression severity. The three factor scores are proposed for external validation.

Introduction: Brain-derived neurotrophic factor (BDNF) has been involved in the pathogenesis of bipolar mood disorder and in the mechanism of mood-normalizing action of lithium. The aim of this study was to find a possible association between lithium prophylactic effect in bipolar patients and two polymorphisms of BDNF gene. Methods: Eighty-eight patients (35 males, 53 females) with bipolar illness were studied. Duration of lithium prophylaxis ranged between 5-27 years (mean 15 years). Three categories of prophylactic lithium response were delineated: excellent responders (ER), partial responders (PR) and non-responders (NR). All patients were genotyped for two polymorphisms of BDNF gene: Val66Met and -270C/T. Results: The Val/Met genotype of Val66Met polymorphism occurred more frequently (p = 0.037) and there was a trend for a higher incidence of Met allele (p = 0.076), in ER than in NR. A trend for C/T genotype and T allele of -270C/T polymorphism was observed to occur more frequently in ER than in NR (p = 0.057 and p = 0.065, respectively). Conclusion: The data obtained suggest that polymorphism of BDNF gene may be connected with a quality of lithium prophylaxis.

Brain-derived neurotrophic factor (BDNF) has been implicated in the pathogenesis of schizophrenia and bipolar disorder. A functional polymorphism Val66Met of BDNF gene was studied in patients with schizophrenia (n=336), bipolar affective disorder (n=352) and healthy controls (n=375). Consensus diagnosis by at least two psychiatrists, according to DSM-IV and ICD-10 criteria, was made for each patient using a structured clinical interview for DSM-IV Axis I disorders (SCID). No association was found between the studied polymorphism and schizophrenia or bipolar affective disorder either for genotype or allele distribution (for genotype: p=0.210 in schizophrenia, p=0.400 in bipolar disorder; for alleles: p=0.260 in schizophrenia, p=0.406 in bipolar disorder). Results were also not significant when analysed by gender. For males genotype distribution and allele frequency were (respectively): p=0.480 and p=0.312 in schizophrenia, p=0.819 and p=0.673 in bipolar affective disorder. Genotype distribution and allele frequency observed in the female group were: p=0.258 for genotypes, p=0.482 for alleles in schizophrenia; p=0.432 for genotypes, p=0.464 for alleles in bipolar affective disorder. A subgroup of schizophrenic (n=62) and bipolar affective patients (n=28) with early age at onset (18 years or younger) was analysed (p=0.328 for genotypes, p=0.253 for alleles in schizophrenia; p=0.032 for genotypes, p=0.858 for alleles in bipolar affective disorder).