Despite stewardship efforts, antibiotic use increasing

Well, this is bad news.

I hope we can all agree that antibiotic use creates antibiotic resistance. (Proof, if any were needed, that the universe has a captious sense of humor; but then it has had millennia to practice. OK, sorry for the anthropomorphizing.) The more pressure bacteria are placed under, the more resistant mutants emerge and survive. So the challenge in using antibiotics is to use them sufficiently and not too much: enough to quell infection and save lives, but not so much that the benefit of successful treatment is outweighed by the cost of increased resistance.

That's the theory, anyway. In practice, according to a paper published today in the Archives of Internal Medicine, we're not living up to the plan.

Amy L. Pakyz, Pharm.D. and colleagues at Virginia Commonwealth University surveyed antibiotic use at 22 academic medical centers — tertiary care teaching hospitals, ones that would be most likely to have high awareness of the dangers of resistance and good antibiotic stewardship programs — between 2002 and 2006. And found: Despite all that awareness, antibiotic use is going up, and the use of broad-spectrum agents and vancomycin, MRSA's drug of last resort, is going up most of all.

The third significant observation is the marked increase in vancomycin use during the 5-year period such that it became the single most commonly used antibacterial in this sample of hospitals from 2004 to 2006. ...
The reasons for the continued increase in vancomycin use are likely multifactorial, including the increasing numbers of hospital-acquired infections caused by MRSA and the emergence of community-associated MRSA, all of which encourage greater empirical use of vancomycin.

With only a few new drugs of comparative effectiveness on the market, and none that are significantly better, this is bad news, the authors underline:

Vancomycin use is a risk factor for emergence of vancomycin-intermediate S aureus and vancomycin-resistant S aureus, although these strains are rare in the United States. Of greater concern may be the emergence of low-level resistance in MRSA to vancomycin, referred to as minimum inhibitory concentration (MIC) “creep,” and this is far more common. Strains of MRSA having vancomycin MICs of 2.0 μg/mL are associated with longer median times to clearance of bacteremia compared with strains having MICs of 1.0 μg/mL or less, as well as frank treatment failures.

The cite is: Pakyz, AL et al. Trends in Antibacterial Use in US Academic Health Centers 2002 to 2006. Arch Intern Med. 2008;168(20):2254-2260.