Low vitamin D level associated with impaired lung function in asthma

Patients with asthma exhibit variable response to inhaled corticosteroids (ICS). Vitamin D is hypothesized to exert effects on phenotype and glucocorticoid (GC) response in asthma. Vitamin D is a steroid hormone and a component of a complex endocrine pathway sometimes called 'vitamin D endocrine system' (Medscape, 2012).

54 nonsmoking adults with asthma were enrolled in a study assessing the relationship between serum 25(OH)D (vitamin D) concentrations and lung function and airway hyperresponsiveness (AHR).

FEV(1) was 82.9 % predicted at baseline, the mean serum vitamin D levels was 28 ng/ml.

Higher vitamin D levels were associated with greater lung function, with a 22.7 ml increase in FEV(1) for each nanogram per milliliter increase in vitamin D.

Participants with vitamin D insufficiency (lower than 30 ng/ml) demonstrated increased AHR, with a provocative concentration of methacholine.

The authors concluded that in asthma, reduced vitamin D levels are associated with impaired lung function, increased AHR, and reduced GC response. Supplementation of vitamin D levels may improve multiple parameters of asthma severity and treatment response.

References:

Vitamin D levels, lung function, and steroid response in adult asthma. Sutherland ER, Goleva E, Jackson LP, Stevens AD, Leung DY. Am J Respir Crit Care Med. 2010 Apr 1;181(7):699-704. Epub 2010 Jan 14.
Cord-blood level of vit D had inverse association with risk of resp infection and childhood wheezing, but not asthma. Pediatrics, 2010. http://goo.gl/Rjnl5
Low vitamin D at age 6 was a predictor of atopy and asthma at 14 http://goo.gl/LJCmX
Both low and high levels of cord blood 25(OH) vitamin D were associated with increased aeroallergen sensitization. JACI, 2011.
Image source: Wikipedia, public domain.

No comments:

Post a Comment