New research shows that vitamin D deficiency is prevalent among patients with interstitial lung disease (ILD), with the largest prevalence seen in patients with concurrent connective tissue disease (CTD). Researchers from the University of Cincinnati College of Medicine evaluated vitamin D levels in 67 patients with CTD-ILD and 51 patients with other forms of ILD. Results showed the overall prevalence of vitamin D deficiency and insufficiency was 38 percent and 59 percent, respectively. Those with CTD-ILD were more likely to have vitamin D deficiency (52 percent vs 20 percent) and insufficiency (79 percent vs 31 percent) than other forms of ILD. Among patients with CTD-ILD, reduced vitamin D levels were strongly associated with reduced lung function. Researchers conclude that vitamin D may have a role in the pathogenesis of CTD-ILD. This article is published in the February issue of Chest, the peer-reviewed journal of the American College of Chest Physicians: Chest 2011; 139(2):353-360.

INFLUENZA A(H1N1) MORTALITY NOT INCREASED BY OBESITY

New research suggests that obesity may not influence mortality rates among patients with influenza A(H1N1); however obese patients with the virus may have longer ICU and hospital stays. Researchers from Spain compared mortality rates and hospital/ICU resource consumption between 150 obese patients with influenza A(H1N1) and 266 patients with influenza A(H1N1) who were not obese. Results showed that obese patients were supported by mechanical ventilation longer and had longer ICU and hospital lengths of stay than patients who were not obese. However, after adjusting for severity and potential confounding variables, obesity was not associated with ICU mortality. The article is published in the February issue ofChest, the peer-reviewed journal of the American College of Chest Physicians: Chest 2011; 139(2):382-386.

CYSTEINE A POTENTIAL BIOMARKER FOR SLEEP APNEA

A new study indicates that the amino acid cysteine may be a biomarker for the development of obstructive sleep apnea (OSA) in obese and nonobese patients. Brazilian researchers compared plasma levels of cysteine in 75 patients with OSA with 75 control subjects. Results showed that cysteine plasma levels were higher in patients with OSA compared with the control subjects. A subgroup of lean patients (BMI < 25) with OSA also had higher cysteine levels than the control subjects. Furthermore, patients with OSA who received continuous positive airway pressure showed a decrease in plasma levels of cysteine after 6 months. Researchers conclude that cysteine is a potential biomarker for OSA and that obesity does not influence its function as a biomarker. The article is published in the February issue of Chest, the peer-reviewed journal of the American College of Chest Physicians: Chest 2011; 139(2):246-252.