Exaggerated Pulmonary Hypertension During Mild Exercise in Chronic Mountain Sickness

Chronic mountain sickness (CMS) is an important public health problem and is characterized by exaggerated hypoxemia, erythrocytosis, and pulmonary hypertension. While pulmonary hypertension is a leading cause of morbidity and mortality in patients with CMS, it is relatively mild and its underlying mechanisms are not known. We speculated that during mild exercise associated with daily activities, pulmonary hypertension in CMS is much more pronounced.

TNFR1 is essential for CD40, but not for lipopolysaccharide-induced sickness behavior and clock gene dysregulation

Autoimmune and infectious diseases are associated with behavioral changes referred to as sickness behavior syndrome (SBS). In autoimmunity, the generation of anti-self T lymphocytes and autoantibodies critically involves binding of CD40 ligand on T-cells to its receptor CD40 on B-cells, dendritic cells and macrophages. Activation of CD40 leads to production of proinflammatory cytokines and, as shown here, induces SBS. Here we report that these behavioral changes depend on the expression of tumor necrosis factor alpha receptor 1 (TNFR1), but not on interleukin-1 receptor 1 or interleukin-6. Moreover, the intensity of SBS correlates with suppression of E-box controlled clock genes, including Dbp, and upregulation of Bmal1. However, the absence of TNFR1 does not interfere with the development of SBS and dysregulation of clock genes in mice treated with lipopolysaccharide. Thus, our results suggest that TNFR1 mediates SBS and dysregulation of clock genes in autoimmune diseases.

Reproducibility of acute mountain sickness in children and adults: a prospective study

Although a history of previous acute mountain sickness (AMS) is commonly used for providing advice and recommending its prophylaxis during subsequent exposure, the intraindividual reproducibility of AMS during repeated high-altitude exposure has never been examined in a prospective controlled study.

Systemic vascular dysfunction in patients with chronic mountain sickness

Chronic mountain sickness (CMS) is a major public health problem characterized by exaggerated hypoxemia and erythrocytosis. In more advanced stages, patients with CMS often present with functional and structural changes of the pulmonary circulation, but there is little information on the systemic circulation. In patients with diseases associated with chronic hypoxemia at low altitude, systemic vascular function is altered. We hypothesized that patients with CMS have systemic vascular dysfunction that may predispose them to increased systemic cardiovascular morbidity.

Predictors of sickness absence in patients with a new episode of low back pain in primary care

This study examines predictors of sickness absence in patients presenting to a health practitioner with acute/ subacute low back pain (LBP). Aims of this study were to identify baseline-variables that detect patients with a new LBP episode at risk of sickness absence and to identify prognostic models for sickness absence at different time points after initial presentation. Prospective cohort study investigating 310 patients presenting to a health practitioner with a new episode of LBP at baseline, three-, six-, twelve-week and six-month follow-up, addressing work-related, psychological and biomedical factors. Multivariate logistic regression analysis was performed to identify baseline-predictors of sickness absence at different time points. Prognostic models comprised 'job control', 'depression' and 'functional limitation' as predictive baseline-factors of sickness absence at three and six-week follow-up with 'job control' being the best single predictor (OR 0.47; 95%CI 0.26-0.87). The six-week model explained 47% of variance of sickness absence at six-week follow-up (p<0.001). The prediction of sickness absence beyond six-weeks is limited, and health practitioners should re-assess patients at six weeks, especially if they have previously been identified as at risk of sickness absence. This would allow timely intervention with measures designed to reduce the likelihood of prolonged sickness absence.

Exercise induces rapid interstitial lung water accumulation in patients with chronic mountain sickness

Chronic mountain sickness (CMS) is a major public health problem in mountainous regions of the world. In its more advanced stages, exercise intolerance is often found, but the underlying mechanism is not known. Recent evidence indicates that exercise-induced pulmonary hypertension is markedly exaggerated in CMS. We speculated that this problem may cause pulmonary fluid accumulation and aggravate hypoxemia during exercise.