Meta-analytical evidence suggests that brain-derived neurotrophic factor (BDNF) is altered in various psychiatric disorders. However, meta-analyses may be hampered by the heterogeneity of BDNF assays, lack of BDNF standard values and heterogeneity among the populations included in the studies. To address these issues, our study aimed to test, in a ‘true-to-life' setting, the hypothesis that the serum BDNF level is nonspecifically reduced in acute severe mental illness (SMI) patients and increases during inpatient treatment. Consecutive samples of 236 inpatients with SMI and 100 healthy controls were recruited. SMI includes schizophrenia and severe mood disorders, and is characterized in the sample by the presence of at least 2 years of psychiatric treatment and disability. Generalized estimating equations were used to analyze BDNF serum levels at admission and upon discharge controlled by confounding factors. BDNF levels increased significantly between admission and discharge in SMI patients. BDNF levels showed significant reductions compared with controls both at admission and upon discharge. In addition, BDNF levels showed no difference among SMI patient diagnostic subgroups (unipolar depression, bipolar depression, schizophrenia and manic episode). The increase but non-restoration of BDNF levels, even with the general acute improvement of clinical scores, may reflect the progression of the disorder characteristically seen in these patients. BDNF levels could be considered as a marker for the presence of a nonspecific psychiatric disorder and possibly a transdiagnostic and nonspecific marker of disease activity.

There is evidence that the brain-derived neurotrophic factor (BDNF) has implications for the pathophysiology of major depressive disorders (MDD). Measures of BDNF levels are highly dependent on the methodologies used and these vary among different studies. Therefore, the aim of this study was to carry out a descriptive analysis of the methodologies used to measure BDNF in clinical trials (CT) in patients with the diagnosis of major depression. We conducted a qualitative systematic review of CT that included samples of subjects diagnosed with major depression and evaluated the BDNF levels as an outcome. The search was performed on Pubmed, Scielo, Psychinfo and Lilacs. The selected articles were analyzed according to the CONSORT Statement and their methods of BDNF collection and analysis were described. Twenty-eight studies were included in the final analysis. Of those, 6 trials (21.4%) involved non-pharmacological interventions and only half had the MDD diagnosis based on structured interview. Trials used different methods to evaluate BDNF levels: most of them verified serum BDNF levels, 17 (60.7%) trials mentioned that measured BDNF levels in duplicate and 9 (32.1%) collected blood in fasting. A variety of methods for BDNF collection and analysis was used in the different studies, making it difficult to compare results. However, despite of the methodology, BDNF seems to increase after treatment for major depression.

Decreased pulse pressure (PP) is associated with low cardiac output and increased mortality in heart failure (HF) inpatients. QRS width is a well-known prognostic factor in HF. The study purpose was to explore the mortality effect of combining PP and QRS width in HF outpatients. Initial sphygmomanometrically determined PP and QRS width on the first electrocardiograph in 327 consecutive patients at an HF clinic were recorded. According to PP > or = or <40 mm Hg and QRS width > or = or <120 ms, patients were classified into 4 groups. Study groups were analyzed for their effect on mortality using Cox proportional hazards regression analysis. Patients with PP <40 mm Hg had higher mortality (59% vs 45%; P=.015). QRS width > or =120 ms indicated a trend toward higher mortality (57% vs 48%; P=.067). Actuarial survival curves showed that group 4 (QRS width > or =120 ms and PP <40 mm Hg) had significant increased mortality risk in 3.5 years' mean follow-up. Group 4 had a mean survival time of 1124 days (SD=124) vs 2233 days (SD=285) in group 1 (QRS width <120 ms and PP > or =40 mm Hg) (P=.022). There was a linear association between left ventricular ejection fraction (LVEF) and study groups. PP and QRS width are readily available, inexpensive, and relevant clinical measures to help identify HF outpatients with significantly worse prognosis and decreased LVEF.