Most patients with interstitial lung disease -- particularly those with autoimmune-related connective tissue diseases -- may have insufficient vitamin D, a single-center study showed.
Among 118 patients with interstitial lung disease (half with underlying conditions such as rheumatoid arthritis, systemic lupus, scleroderma, Wegener's granulomatosis, and Sjögren's syndrome) 59% had insufficient serum levels of 25-hydroxyvitamin D3 and 38% were judged to be vitamin D deficient, Brent Kinder, MD, of the University of Cincinnati, and colleagues reported in Chest.
Compared with patients with other types of interstitial lung disease, those with connective tissue diseases were significantly more likely to have vitamin D insufficiency (79% versus 31%) and a deficiency (52% versus 20%), Kinder and co-authors noted.
The lower vitamin D levels were associated with reduced lung function, they added.
"These findings have important implications for important interstitial lung disease comorbidities such as osteoporosis and opportunistic infections, and possibly the underlying fibrogenic process," the researchers wrote.
"Beyond the impact on bone health, the strong association of vitamin D deficiency with the presence of connective tissue disease seen in this and other studies suggests a possible pathogenic role of vitamin D in autoimmune disorders, which frequently have life-threatening manifestations in the lung."
Kinder and his colleagues assessed the prevalence of vitamin D deficiency in a cohort of patients with interstitial lung disease, who are often treated with corticosteroids. The detrimental effect of chronic use of corticosteroids on bone health has been well established, according to the researchers.
Of the patients included in the study, 51 had interstitial lung disease and 67 had other forms of interstitial lung disease related to autoimmune connective tissue diseases.
http://www.medpagetoday.com/Pulmonology/GeneralPulmonary/24169