Vitamin D, innate immunity and outcomes in community acquired pneumonia.
OBJECTIVE
Vitamin D regulates the production of the antimicrobial peptides cathelicidin and beta-defensin-2, which play an important role in the innate immune response to infection. We hypothesized that vitamin D deficiency would be associated with lower levels of these peptides and worse outcomes in patients admitted to hospital with community acquired pneumonia.


METHODS
Associations between mortality and serum levels of 25-hydroxyvitamin D, cathelicidin and beta-defensin-2 were investigated in a prospective cohort of 112 patients admitted with community acquired pneumonia during winter.


RESULTS
Severe 25-hydroxyvitamin D deficiency (<30nmol/L) was common in this population (15%) and was associated with a higher 30-day mortality compared with patients with sufficient 25-hydroxyvitamin D (>50nmol/L) (odds ratio 12.7, 95% confidence interval: 2.2-73.3, P=0.004). These associations were not explained by differences in age, comorbidities, or the severity of the acute illness. Neither cathelicidin nor beta-defensin-2 levels predicted mortality, although there was a trend towards increased mortality with lower cathelicidin (P=0.053). Neither cathelicidin nor beta-defensin-2 levels correlated with 25-hydroxyvitamin D.


CONCLUSIONS
25-hydroxyvitamin D deficiency is associated with increased mortality in patients admitted to hospital with community acquired pneumonia during winter. Contrary to our hypothesis, 25-hydroxyvitamin D levels were not associated with levels of cathelicidin or beta-defensin-2.
Respiratory Research Unit, Waikato Hospital Department of Molecular Genetics, University of Waikato, Hamilton Department of Preventive and Social Medicine, University of Otago, Dunedin, New Zealand.
Leong
L
Leow
Talia
T
Simpson
Ray
R
Cursons
Noel
N
Karalus
Robert J
RJ
Hancox
D000208:Acute Disease; D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D023181:Antimicrobial Cationic Peptides / Q000097:blood / Q000276:immunology; D015331:Cohort Studies; D017714:Community-Acquired Infections / Q000097:blood / Q000276:immunology* / Q000401:mortality; D005260:Female; D006801:Humans; D007113:Immunity, Innate; D008297:Male; D008875:Middle Aged; D011014:Pneumonia / Q000097:blood / Q000276:immunology* / Q000401:mortality; D011446:Prospective Studies; D012720:Severity of Illness Index; D016896:Treatment Outcome; D014807:Vitamin D / Q000097:blood / Q000276:immunology*; D014808:Vitamin D Deficiency / Q000276:immunology; D055815:Young Adult; D023083:beta-Defensins / Q000097:blood / Q000276:immunology; D054804:Cathelicidins
D023181:Antimicrobial Cationic Peptides; C106641:DEFB4A protein, human; D023083:beta-Defensins; D014807:Vitamin D; D054804:Cathelicidins