Associations between jet lag and cortisol diurnal rhythms after domestic travel.

Objective: Millions of adults in the United States travel abruptly across time zones each year. Nevertheless, the impact of traveling over relatively short distances (across 3 or fewer time zones) on diurnal patterning of typical physiological response patterns has yet to be studied in a large, epidemiological sample. Design: The current research focuses on 764 middle-aged men comparing variations in diurnal cortisol regulation based on number of time zones traveled eastward or westward the day before. Main Outcome Measure: Participants provided samples of salivary cortisol at waking, 30-min postwaking, 10 a.m., 3 p.m., and bedtime. Results: Eastward travel was associated with a steeper salivary cortiso

Impact of age on the levels and utility of novel cardiac biomarkers in diagnosing acute heart failure: results from the BACH Multinational Study

Background: B-type natriuretic peptide (BNP) levels are useful in the diagnosis of heart failure (HF) in patients with acute dyspnea, but their diagnostic value is confounded by age. We examined the impact of age on the levels and utility of novel cardiac biomarkers in a secondary analysis of the Biomarkers in ACute Heart Failure (BACH) study. Methods: The BACH study was a multinational 15-center prospective study of the use of novel cardiovascular prohormone fragments in diagnosing HF among dyspneic patients presenting to the ED. HF diagnosis was determined by 2 independent cardiologists who were blinded to the ED physicians’ diagnoses and to the biomarker levels being examined in this study. Results: The mean age of the 1641 subjects was 64±17 years; the 568 (35%) patients with a final diagnosis of HF were older than those with alternate diagnoses (71 vs. 60 years, p <0.001). In patients without acute HF, median levels of all BACH markers (CTproET, MR-proADM, MR-proANP, CT-proAVP) increased significantly with increasing age group (p <0.001), as did levels of MR-proADM (p=0.001) and MR-proANP (p=0.025) in subjects with HF. The area under the ROC curve was largest in the youngest age group and decreased with age, suggesting that the BACH markers were stronger predictors in younger patients Conclusions: The utility of the studied prohormone biomarkers for diagnosing acute HF varies by age. The BACH biomarkers proved to be a powerful adjunct to the diagnosis of HF, especially in younger patient

Effect of race on the diagnostic performance of novel cardiovascular biomarkers in patients with dyspnea: results from the BACH multinational study

Background: The Biomarkers in Acute Heart Failure (BACH) study examined the utility of a panel of novel prohormone cardiovascular biomarkers in diagnosing heart failure (HF), but little is known about how levels of these markers vary between racial groups. Methods: 1641 patients presenting to the ED with acute dyspnea were enrolled in the prospective, multinational, 15-center BACH trial, and plasma levels of several prohormone biomarker fragments were measured. The diagnosis of HF was determined by 2 independent cardiologists, blinded to the ED physicians’ diagnoses and to the biomarker levels being examined in the trial. Race was determined by self-report. Results: Of the 1626 patients of known race, 67% were white and 29% were black. White patients were more likely to have a final diagnosis of HF than black patients (40% vs. 25%, p <0.001). Median levels of all BACH markers except CT-proAVP were lower in blacks than in whites among patients with a final diagnosis other than acute HF; in those with acute HF, levels differed by race only for MR-proANP, which was higher in blacks (519 pmol/L vs. 395 pmol/L, p=0.002). All BACH markers were stronger predictors of HF in blacks than in whites, with MR-proANP emerging as an especially powerful predictor in blacks (AUC=0.946, Figure). Adjusting for age did not materially alter the results. Conclusions: Novel prohormone biomarkers performed better in blacks than in whites for diagnosing acute HF. MR-proANP proved an especially accurate predictor in black patient