title: Testosterone deficiency increases hospital readmission and mortality rates in male patients with heart failure.
abstract: BACKGROUND
  Testosterone deficiency in patients with heart failure (HF) is associated with decreased exercise capacity and mortality; however, its impact on hospital readmission rate is uncertain. Furthermore, the relationship between testosterone deficiency and sympathetic activation is unknown.
  
  
  OBJECTIVE
  We investigated the role of testosterone level on hospital readmission and mortality rates as well as sympathetic nerve activity in patients with HF.
  
  
  METHODS
  Total testosterone (TT) and free testosterone (FT) were measured in 110 hospitalized male patients with a left ventricular ejection fraction < 45% and New York Heart Association classification IV. The patients were placed into low testosterone (LT; n = 66) and normal testosterone (NT; n = 44) groups. Hypogonadism was defined as TT < 300 ng/dL and FT < 131 pmol/L. Muscle sympathetic nerve activity (MSNA) was recorded by microneurography in a subpopulation of 27 patients.
  
  
  RESULTS
  Length of hospital stay was longer in the LT group compared to in the NT group (37 ± 4 vs. 25 ± 4 days; p = 0.008). Similarly, the cumulative hazard of readmission within 1 year was greater in the LT group compared to in the NT group (44% vs. 22%, p = 0.001). In the single-predictor analysis, TT (hazard ratio [HR], 2.77; 95% confidence interval [CI], 1.58-4.85; p = 0.02) predicted hospital readmission within 90 days. In addition, TT (HR, 4.65; 95% CI, 2.67-8.10; p = 0.009) and readmission within 90 days (HR, 3.27; 95% CI, 1.23-8.69; p = 0.02) predicted increased mortality. Neurohumoral activation, as estimated by MSNA, was significantly higher in the LT group compared to in the NT group (65 ± 3 vs. 51 ± 4 bursts/100 heart beats; p < 0.001).
  
  
  CONCLUSIONS
  These results support the concept that LT is an independent risk factor for hospital readmission within 90 days and increased mortality in patients with HF. Furthermore, increased MSNA was observed in patients with LT.
authors.affiliation: Instituto do Coração, Faculdade de Medicina, Universidade de São Paulo, BR.
authors.forename: Marcelo Rodrigues dos
authors.initials: MR
authors.lastname: Santos
authors.affiliation: Instituto do Coração, Faculdade de Medicina, Universidade de São Paulo, BR.
authors.forename: Ana Luiza Carrari
authors.initials: AL
authors.lastname: Sayegh
authors.affiliation: Instituto do Coração, Faculdade de Medicina, Universidade de São Paulo, BR.
authors.forename: Raphaela Vilar Ramalho
authors.initials: RV
authors.lastname: Groehs
authors.affiliation: Instituto do Coração, Faculdade de Medicina, Universidade de São Paulo, BR.
authors.forename: Guilherme
authors.initials: G
authors.lastname: Fonseca
authors.affiliation: Instituto do Coração, Faculdade de Medicina, Universidade de São Paulo, BR.
authors.forename: Ivani Credidio
authors.initials: IC
authors.lastname: Trombetta
authors.affiliation: Instituto do Coração, Faculdade de Medicina, Universidade de São Paulo, BR.
authors.forename: Antônio Carlos Pereira
authors.initials: AC
authors.lastname: Barretto
authors.affiliation: Faculdade de Medicina, Universidade de São Paulo, BR.
authors.forename: Marco Antônio
authors.initials: MA
authors.lastname: Arap
authors.affiliation: Instituto do Coração, Faculdade de Medicina, Universidade de São Paulo, BR.
authors.forename: Carlos Eduardo
authors.initials: CE
authors.lastname: Negrão
authors.affiliation: Division of Cardiology, David Geffen School of Medicine, University of California, US.
authors.forename: Holly R
authors.initials: HR
authors.lastname: Middlekauff
authors.affiliation: Instituto do Coração, Faculdade de Medicina, Universidade de São Paulo, BR.
authors.forename: Maria-Janieire de Nazaré Nunes
authors.initials: MJ
authors.lastname: Alves
mesh_terms: D004812:Epidemiologic Methods; D006333:Heart Failure / Q000401:mortality*; D006801:Humans; D007902:Length of Stay; D008297:Male; D008875:Middle Aged; D010359:Patient Readmission; D012016:Reference Values; D013318:Stroke Volume / Q000502:physiology; D013564:Sympathetic Nervous System / Q000503:physiopathology; D013739:Testosterone / Q000032:analysis / Q000172:deficiency*; D013997:Time Factors; D016277:Ventricular Function, Left / Q000502:physiology
chemical_list: D013739:Testosterone