Penicillin allergy associated with risk of MRSA, C. diff, due to use of other antibiotics
Penicillin allergy was associated with an increased risk of methicillin-resistant Staphylococcus aureus (MRSA) and Clostridium difficile that was mediated by the increased use of alternatives to beta-lactam antibiotics, a study found.
To evaluate the relationship between penicillin allergy and MRSA and C. difficile, researchers conducted a population-based, matched-cohort study among general practices in the United Kingdom from 1995 to 2015. There were 301,399 adults without previous MRSA or C. difficile enrolled in the Health Improvement Network database, of whom 64,141 had a penicillin allergy and 237,258 were comparators matched on age, sex, and study entry time.
The study's primary outcome was risk of incident MRSA and C. difficile, while secondary outcomes were use of beta-lactam antibiotics and beta-lactam alternative antibiotics. Results were published June 27 by The BMJ.
Among the cohort, 1,365 developed MRSA (442 participants with penicillin allergy and 923 comparators) and 1,688 developed C. difficile (442 participants with penicillin allergy and 1,246 comparators) during a mean of 6.0 years of follow-up. Among patients with penicillin allergy, the adjusted hazard ratio was 1.69 (95% CI, 1.51 to 1.90) for MRSA and 1.26 (95% CI, 1.12 to 1.40) for C. difficile. The adjusted incidence rate ratios for antibiotic use in this group were 4.15 (95% CI, 4.12 to 4.17) for macrolides, 3.89 (95% CI, 3.66 to 4.12) for clindamycin, and 2.10 (95% CI, 2.08 to 2.13) for fluoroquinolones. Increased use of beta-lactam alternative antibiotics accounted for 55% of the increased risk of MRSA and 35% of the increased risk of C. difficile, the authors noted.
Systematically addressing penicillin allergies may be an important public health strategy to reduce the incidence of MRSA and C. difficile among patients labeled with a penicillin allergy, the authors wrote.
“Use of the most narrow spectrum antibiotic that is effective for a given infection is a cornerstone of evidence based treatment for infection and is responsible antibiotic stewardship,” the researchers wrote. “Antibiotic stewardship committees enforce this aim in the hospital setting, with evaluations for penicillin allergy occasionally included in stewardship efforts. This analysis emphasises the importance of performing outpatient antibiotic stewardship and the role that penicillin allergy evaluations might play.”
Fewer Medicare beneficiaries dying in the hospital, but ICU use at end of life still common
From 2000 to 2015, Medicare fee-for-service beneficiaries became less likely to die in a hospital, but more than a quarter were treated in an ICU in the last month of life, a recent study found.
The retrospective cohort study included a 20% random sample of Medicare fee-for-service beneficiaries (a total of 1,361,870 decedents; mean age, 82.8 years; 58.7% women) who died in 2000, 2005, 2009, 2011, or 2015. Researchers also analyzed all 871,845 Medicare Advantage beneficiaries who died in 2011 or 2015 (mean age, 82.1 years; 54.0% women). Results were published by JAMA on June 25 and appeared in the July 17 issue.
Among Medicare fee-for-service decedents, the proportion of deaths occurring in an acute care hospital decreased from 32.6% in 2000 to 19.8% in 2015. Deaths in a home or community setting (including assisted living facilities) increased from 30.7% in 2000 to 40.1% in 2015. ICU use during the last 30 days of life was 24.3% in 2000 and increased after that, but stabilized between 2009 and 2015 at 29.0%. Health care transitions during the last three days of life, which the study authors considered a burdensome pattern of care, increased from 10.3% in 2000 to a high of 14.2% in 2009 and decreased to 10.8% in 2015.
The study of Medicare Advantage decedents found that the number of patients in that program during the last 90 days of life increased from 358,600 in 2011 to 513,245 in 2015. The Medicare Advantage decedents showed similar patterns in the rates for site of death, place of care, and health care transitions as those in the fee-for-service program, although the authors noted that Medicare Advantage decedents were less likely to be hospitalized, less likely to die in a nursing home, and more likely to die in the community.
The causes of the findings are uncertain, according to the study authors. “It is difficult to disentangle efforts such as public education, promotion of advance directives through the Patient Self-Determination Act, increased access to hospice and palliative care services, financial incentives of payment policies, and other secular changes,” they wrote. The stabilization in rates of ICU use at the end of life should be seen as an important marker of improvement, the authors said.
A significant limitation of the study is that Medicare billing data do not differentiate whether a community death occurred in a personal home, an assisted living facility, or a foster care home unless the decedent was receiving hospice services, the authors noted. Many of the patients who died in the community likely died in assisted living facilities, and future research should “examine whether death in an assisted living facility is similar to the experience of death in a nursing home or in a private home while receiving hospice services,” the authors wrote.