That's exactly the question the CDC is asking too, says Arjun Srinivasan, MD, CDC medical epidemiologist and associate director for the agency's Healthcare Associated Infection Prevention Programs. There's strong indications that's where a chunk of the problem might lie.
"That's what we've seen from some studies," Srinivasan confirms. "Just yesterday someone sent me an abstract presented at a meeting which actually showed that the rates of antibiotic use were somewhat higher in small hospitals compared to larger hospitals. There's a lot we have to learn about what underlies this variation."
Srinivasan sent me the abstract, authored by clinicians at Ascension Health, a St. Louis, MO-based system with more than 80 hospitals in 21 states.
It's titled "Does Size Matter? Systemwide Variation of Antimicrobial Utilization" and features a review of antibiotic prescribing practices at 69 Ascension hospitals. This team, too, found significant variation in use of antibiotics across the Ascension system.
But counterintuitively, they found that the lower the "case mix index," or severity of illness at a particular hospital, and the smaller the hospital in terms of number of beds, the more antibiotics were used on patients and the more money was spent on the cost of those drugs.
Less sick patients = more antibiotics? Smaller hospital = more antibiotics? Yes, you got that right.
"Likely smaller hospitals do not have as robust of an antimicrobial stewardship program as larger hospitals," the authors write. "Largest hospital: very strict control on antibiotics with very active pharmacy and Infectious Diseases physicians involvement."