The role of vitamin D in pulmonary disease: COPD, asthma, infection, and cancer

The role of vitamin D (VitD) in calcium and bone homeostasis is well described. In the last years, it has been recognized that in addition to this classical function, VitD modulates a variety of processes and regulatory systems including host defense, inflammation, immunity, and repair. VitD deficiency appears to be frequent in industrialized countries. Especially patients with lung diseases have often low VitD serum levels. Epidemiological data indicate that low levels of serum VitD is associated with impaired pulmonary function, increased incidence of inflammatory, infectious or neoplastic diseases. Several lung diseases, all inflammatory in nature, may be related to activities of VitD including asthma, COPD and cancer. The exact mechanisms underlying these data are unknown, however, VitD appears to impact on the function of inflammatory and structural cells, including dendritic cells, lymphocytes, monocytes, and epithelial cells. This review summarizes the knowledge on the classical and newly discovered functions of VitD, the molecular and cellular mechanism of action and the available data on the relationship between lung disease and VitD status

The placebo effect of hyperbaric oxygen therapy - fact or fiction?

BACKGROUND: Patients undergoing hyperbaric oxygen therapy (HBO) frequently report improvement in their health status; however, it is debatable whether this is a true effect of HBO or a placebo. We aimed to investigate the placebo effect of receiving HBO. METHODS: 18 Patients with diabetic foot ulcers were randomised, in a double blind study, either to receive hyperbaric 100percent oxygen (treatment group) or hyperbaric air (placebo group), at 2.4 atmospheres of absolute pressure for 90 minutes daily, for a total of 30 treatments. Two generic health status questionnaires, SF-36 Health Survey and HADS (Hospital Anxiety and Depression Scale) were used to assess the patients before commencing the treatment, and after day 1, day 15 and day 30. RESULTS: HADS detected a significant reduction in the depression score in both groups (p=0.001) and a significant reduction in anxiety levels in the control group (p=0.025). In five of the eight domains of the SF-36, the treatment had no significant effect in either group. Patients in the treatment group reported significant improvement in the General Health domain (p=0.008), in the Vitality domain (p=0.01), in the Mental Health domain (p=0.05), and in their overall Health Transition (p=0.04). In contrast, there was no significant difference in the placebo group in all domains of the SF-36. CONCLUSION: Patients receiving hyperbaric oxygen reported a significant improvement in their health related quality of life. In contrast, the placebo effect of hyperbaric therapy as measured by SF-36 was insignificant. Nevertheless, HADS has detected a significant reduction in both anxiety and depression scores in the placebo group