Reduced Dietary Sodium Intake Increases Heart Rate. A Meta-Analysis of 63 Randomized Controlled Trials Including 72 Study Populations

Reduced dietary sodium intake (sodium reduction) increases heart rate in some studies of animals and humans. As heart rate is independently associated with the development of heart failure and increased risk of premature death a potential increase in heart rate could be a harmful side-effect of sodium reduction. The purpose of the present meta-analysis was to investigate the effect of sodium reduction on heart rate. Relevant studies were retrieved from an updated pool of 176 randomized controlled trials (RCTs) published in the period 1973–2014. 63 of the RCTs including 72 study populations reported data on heart rate. In a meta-analysis of these data sodium reduction increased heart rate with 1.65 beats per minute [95% CI: 1.19, 2.11], p < 0.00001, corresponding to 2.4% of the baseline heart rate. This effect was independent of baseline blood pressure. In conclusion sodium reduction increases heart rate by as much (2.4%) as it decreases blood pressure (2.5%). This side-effect, which may cause harmful health effects, contributes to the need for a revision of the present dietary guidelines

Increased serum YKL-40 in patients with pulmonary sarcoidosis--a potential marker of disease activity?

SummaryBackground: YKL-40, a growth factor for fibroblasts and vascular endothelial cells, is secreted by macrophages and neutrophils. Elevated serum YKL-40 is found in patients with diseases characterized by inflammation, tissue remodelling and ongoing fibrosis. The aim was to evaluate whether macrophages and giant cells in the granulomatous sarcoid lesions of patients with pulmonary sarcoidosis produce YKL-40 and to determine whether serum YKL-40 in these patients were associated with disease activity.Methods: Serum YKL-40 was determined by radioimmunoassay in 27 patients with a histological diagnosis of pulmonal sarcoidosis. Immunohistochemical staining for YKL-40 antigen was performed in five biopsies with pulmonary sarcoid lesions. Serum YKL-40 was likewise measured in 173 healthy age-matched control subjects.Results: Mononuclear cells/macrophages and giant cells in pulmonary sarcoid granulomas expressed YKL-40 protein. Serum YKL-40 was higher in patients with pulmonary sarcoidosis compared to controls (P<0.001) and 63% had elevated serum YKL-40. There was a positive correlation between serum YKL-40 and serum angiotensin converting enzyme (rho=0.55, P=0.0053). Patients with serum YKL-40>median value in the patient group had lower carbon monoxide diffusion capacity corrected for alveolar volume (DLCO/VA) than patients with serum YKL-40⩽the median value (P=0.015).Conclusions: Serum YKL-40 may be a novel biomarker of sarcoid disease activity and ongoing fibrosis in patients with pulmonary sarcoidosis