Low red cell folate levels are associated with poor response to nortriptyline in major depression

Biomarkers as predictors of treatment response to tricyclic antidepressants in major depressive disorder: A systematic review

Tricyclic antidepressants (TCAs) are frequently prescribed in case of non-response to first-line antidepressants in Major Depressive Disorder (MDD). Treatment of MDD often entails a trial-and-error process of finding a suitable antidepressant and its appropriate dose. Nowadays, a shift is seen towards a more personalized treatment strategy in MDD to increase treatment efficacy. One of these strategies involves the use of biomarkers for the prediction of antidepressant treatment response. We aimed to summarize biomarkers for prediction of TCA specific (i.e. per agent, not for the TCA as a drug class) treatment response in unipolar nonpsychotic MDD. We performed a systematic search in PubMed and MEDLINE. After full-text screening, 36 papers were included. Seven genetic biomarkers were identified for nortriptyline treatment response. For desipramine, we identified two biomarkers; one genetic and one nongenetic. Three nongenetic biomarkers were identified for imipramine. None of these biomarkers were replicated. Quality assessment demonstrated that biomarker studies vary in endpoint definitions and frequently lack power calculations. None of the biomarkers can be confirmed as a predictor for TCA treatment response. Despite the necessity for TCA treatment optimization, biomarker studies reporting drug-specific results for TCAs are limited and adequate replication studies are lacking. Moreover, biomarker studies generally use small sample sizes. To move forward, larger cohorts, pooled data or biomarkers combined with other clinical characteristics should be used to improve predictive power.

Comprehensive review of factors implicated in the heterogeneity of response in depression

BACKGROUND

Heterogeneity in overall response and outcomes to pharmacological treatment has been reported in several depression studies but with few sources that integrate these results. The goal of this study was to review the literature and attempt to identify nongenetic factors potentially predictive of overall response to depression treatments.

METHODS

A comprehensive review of the literature from the last 10 years was performed using three key databases (PubMed, EMBASE, and Cochrane). All relevant studies that met the inclusion criteria were selected and scored for their levels of evidence using the NICE scoring method. A subjective assessment of the strength of evidence for each factor was performed using predefined criteria.

RESULTS

Our broad search yielded 76 articles relevant to treatment heterogeneity. Sociodemographic factors, disease characteristics, and comorbidities were the most heavily researched areas. Some of the factors associated with more favorable overall response include being married, other social support, and low levels of baseline depressive symptoms. Evidence relating to baseline disease severity as a factor predictive of antidepressant response was particularly convincing among the factors reviewed. The presence of comorbid anxiety and pain contributed to worse antidepressant treatment outcomes.

CONCLUSIONS

Several factors either predictive of or associated with overall response to antidepressant treatment have been identified. Inclusion of factors predictive of response in the design of future trials may help tailor treatments to depression patients presenting to the average clinical practice, resulting in improved outcomes.

Nutritional status in patients with major depressive disorders: a pilot study in tabriz, iran

INTRODUCTION

This study was conducted to assess the nutritional status in Iranian major depres¬sive disorder patients. We also determined the relationship between nutrients intake with depres¬sion severity.

METHODS

Seventy major depressive patients were selected randomly from outpatient depressive subjects, referred to Razi Psychiatry Hospital in Tabriz, Iran in 2007. Dietary intakes were rec¬orded and compared with dietary reference intakes (DRIs). Definition of the disease and its se¬verity were according to DSM-IV-TR and Hamilton Depression Rating Scale, respectively. Nu¬tritionist III program, Chi-square, correlation and t-test were used for data analyses. Demo¬graphic, clinical and laboratory data were analyzed using SPSS software for windows (ver¬sion13.0).

RESULTS

According to dietary analysis, 11.4% and 55% of patients had dietary protein and energy deficiency, respectively. 97.1% and 95.7% of patients had less folate and B12 intakes than recom¬mended dietary allowances. The mean (Mean ± SD) for plasma folate and B12 was 5.18±6.11 ng/ml and 389.05±346.9 pg/ml, respectively. Low plasma folate and B12 was observed in 51.4% and 50.0 % of patients, respectively. There was no significant relationship between blood folate and B12 levels with depression severity. Similarly, nutrients intake had no effect on depression se¬verity.

CONCLUSION

Low plasma concentrations and low dietary intakes of folate and B12 are common among Tabrizian depressive patients. It seems that nutritional intervention for increasing folate and vitamin B12 intake must be considered as health promotive and preventative program for patients suffering from depression disorders.