Connect
MJA
MJA

Pneumonia risk stratification in tropical Australia: does the SMART-COP score apply?

William B Grant
Med J Aust 2010; 192 (9): 542-543.
Published online: 3 May 2010

To the Editor: The recent article by Davis and colleagues reported that the SMART-COP score underestimates the severity of pneumonia in tropical northern Australia, but can be improved by using locally relevant additions.1 The authors’ revised scoring system, SMARTACOP, increased the score for an albumin level < 35 g/L and added Aboriginal or Torres Strait Islander status as a variable. While these additions are useful, the reason for adding ethnicity was not fully clarified.

A factor overlooked was low serum 25-hydroxyvitamin D [25(OH)D] levels among dark-skinned Australians.2 Smoking, identified as a marginally insignificant risk factor,1 is also associated with lower serum 25(OH)D levels.3 Vitamin D enhances the innate immune system through induction by 1,25-dihydroxyvitamin D of cathelicidin and defensins, which combat several types of bacterial and viral infections including upper respiratory tract infections.4

In the 1918–1919 influenza pandemic in the United States, many deaths were due to pneumonia that occurred as a complication of influenza infection. An ecological study found that indices for levels of vitamin D production from solar ultraviolet-B irradiance explained 50% of the variance in pandemic case-fatality rates among 12 communities.5 The mechanisms proposed for the beneficial effect of vitamin D were reduced proinflammatory cytokine production, which would reduce damage to the epithelial lining of the lungs, and induction of cathelicidin and defensins to fight the secondary bacterial pneumonia infection.

If sera are available for those included in the Australian SMART-COP study,1 they could be analysed for 25(OH)D levels to test this hypothesis.

  • William B Grant

  • Sunlight, Nutrition, and Health Research Center (SUNARC), San Francisco, Calif, USA.

Correspondence: wbgrant@infionline.net

Competing interests:

I receive funding from the UV Foundation and Bio-Tech-Pharmacal. I received honoraria from the North Coast Cancer Foundation for a talk on vitamin D and breast cancer. I have received funding from the Sunlight Research Forum (The Netherlands) and the Vitamin D Society (Canada) for preparation of other manuscripts.

  • 1. Davis JA, Cross GB, Charles PGP, et al. Pneumonia risk stratification in tropical Australia: does the SMART-COP score apply? Med J Aust 2010; 192: 133-136. <MJA full text>
  • 2. Nowson CA, Margerison C. Vitamin D intake and vitamin D status of Australians. Med J Aust 2002; 177: 149-152. <MJA full text>
  • 3. Brot C, Jorgensen NR, Sorensen OH. The influence of smoking on vitamin D status and calcium metabolism. Eur J Clin Nutr 1999; 53: 920-926.
  • 4. Bartley J. Vitamin D, innate immunity and upper respiratory tract infection. J Laryngol Otol 2010; 13 Jan: 1-5. [Epub ahead of print.]
  • 5. Grant WB, Giovannucci E. The possible roles of solar ultraviolet-B radiation and vitamin D in reducing case-fatality rates from the 1918–1919 influenza pandemic in the United States. Dermatoendocrinol 2009; 1: 215-219.

Author

remove_circle_outline Delete Author
add_circle_outline Add Author

Comment
Do you have any competing interests to declare? *

I/we agree to assign copyright to the Medical Journal of Australia and agree to the Conditions of publication *
I/we agree to the Terms of use of the Medical Journal of Australia *
Email me when people comment on this article

Responses are now closed for this article.