Coffee, Tea, or MRSA?

 

 

# 5691

 

 

An interesting study appears in the Annals of Family Medicine that looks at the rate of nasal carriage of MRSA (methicillin-resistant Staphylococcus aureus) among hot coffee & tea drinkers compared to those who abstain.

 

As we’ve discussed before, a small percentage of the population is known to carry either MRSA or non-resistant S. aureus in their nasal cavities.

 

This from the CDC:

 

Definition of MRSA

While 25% to 30% of people are colonized* in the nose with staph, less than 2% are colonized with MRSA (Gorwitz RJ et al. Journal of Infectious Diseases. 2008:197:1226-34.).

*Colonized:
When a person carries the organism/bacteria but shows no clinical signs or symptoms of infection. For Staph aureus the most common body site colonized is the nose.

 

In Firefighters & Paramedics At Greater Risk Of MRSA from last year, and a follow up called Firefighters & MRSA Revisited from last month we looked at research showing a 10x’s greater incidence of MRSA colonization (20%) among a sampling of firefighters tested in Washington State.

 

Which brings us to today’s study that analyzed data from the 2003–2004 National Health and Nutrition Examination Survey and found that non-institutionalized people who consumed either hot tea or coffee were roughly half as likely to carry MRSA compared to those who didn’t.

 

While interesting, exactly what to make of their findings isn’t clear.

 

Although the authors attempted to account for other external variables (age, income, self-reporting bias) there could be other factors at work here besides just the consumption of these hot beverages.

 

The old adage, "Correlation does not imply causation"  applies.

 

Just because two phenomena tend to happen in close proximity to one another does not necessarily mean that one causes the other.

 

Still . . . the results are intriguing.

 

 

Tea and Coffee Consumption and MRSA Nasal Carriage

Eric M. Matheson, MD, MS, Arch G. Mainous III, PhD, Charles J. Everett, PhD and Dana E. King, MD, MS

Department of Family Medicine, Medical University of South Carolina, Charleston, South Carolina

CONCLUSIONS Consumption of hot tea or coffee is associated with a lower likelihood of MRSA nasal carriage. Our findings raise the possibility of a promising new method to decrease MRSA nasal carriage that is safe, inexpensive, and easily accessible.

 

 

You can read the entire study here, including their methodology which relied on a small subset (n=5555) of the population – deemed to be representative of the greater non-institutionalized population of the United States.

 

The authors conclude by stating:

 

Our findings of reduced odds of MRSA nasal carriage among tea and coffee drinkers raise the possibility of a promising new alternative to antibiotics that is safe, inexpensive, and easily accessible.

 

Perhaps.

But I’m left with one nagging thought.

 

In the two studies I cited on firefighters at the top of the blog, nasal carriage was found to be 10 times higher than the general population.

 

Unless things have changed greatly since I was a paramedic (which admittedly was long ago and in a galaxy far, far away . . . ) – firefighters and paramedics are prodigious consumers of hot coffee.

 

Which – if this latest study is aiming us in the right direction - makes you wonder what their rate of nasal carriage would have been without their daily consumption of copious cups of coffee.

 

I sense another study is needed.