A retrospective cohort study conducted in the USA examined outcomes for 6481 medical patients with pneumonia, closely scrutinizing the rate of excess antibiotic treatment duration. The unit of measure was excess days per 30-day period, calculated by subtracting each patient’s shortest effective (expected) treatment duration (based on a range of clinical variables). Patient outcomes were assessed after 30 days using medical records and phone calls
Two thirds (67.8% [4391 of 6481]) of patients received excess antibiotic therapy, with treatment prescribed at discharge accounting for the lion’s share of excess duration (93.2%). Risk factors for receiving excess treatment included respiratory cultures or non-culture diagnostic testing, a hospital longer stay, receiving a high-risk antibiotic in the prior 90 days, community-acquired pneumonia
Excess treatment was not associated with lower rates of any adverse outcomes (death, readmission, emergency department visit, or C difficile infection, but each excess day of treatment was associated with a 5% increase in the odds of antibiotic-associated adverse events reported after discharge. Sometimes less is more – see the details of the study, published in the Annals of Internal Medicine, here.