Antibiotic prescribing and associated diarrhoea: a prospective cohort study of care home residents

BACKGROUND

the risk factors for and frequency of antibiotic prescription and antibiotic-associated diarrhoea (AAD) among care home residents are unknown.

AIM

to prospectively study frequency and risks for antibiotic prescribing and AAD for care home residents.

DESIGN AND SETTING

a 12-month prospective cohort study in care homes across South Wales.

METHOD

antibiotic prescriptions and the development of AAD were recorded on case report forms. We defined AAD as three or more loose stools in a 24-h period occurring within 8 weeks of exposure to an antibiotic.

RESULTS

we recruited 279 residents from 10 care homes. The incidence of antibiotic prescriptions was 2.16 prescriptions per resident year (95% CI: 1.90-2.46). Antibiotics were less likely to be prescribed to residents from dual-registered homes (OR compared with nursing homes: 0.38, 95% CI: 0.18-0.79). For those who were prescribed antibiotics, the incidence of AAD was 0.57 episodes per resident year (95% CI: 0.41-0.81 episodes). AAD was more likely in residents who were prescribed co-amoxiclav (hazards ratio, HR = 2.08, 95% confidence interval, CI: 1.18-3.66) or routinely used incontinence pads (HR = 2.54, 95% CI: 1.26-5.13) and less likely in residents from residential homes (HR compared with nursing homes: 0.14, 95% CI: 0.06-0.32).

CONCLUSION

residents of care homes, particularly of nursing homes, are frequently prescribed antibiotics and often experience diarrhoea following such prescriptions. Co-amoxiclav is associated with greater risk of AAD.

Probiotics for Antibiotic-Associated Diarrhoea (PAAD): a prospective observational study of antibiotic-associated diarrhoea (including Clostridium difficile-associated diarrhoea) in care homes

BACKGROUND

Antibiotic prescribing rates in care homes are higher than in the general population. Antibiotics disrupt the normal gut flora, sometimes causing antibiotic-associated diarrhoea (AAD). Clostridium difficile (Hall and O'Toole 1935) Prévot 1938 is the most commonly identified cause of AAD. Little is known either about the frequency or type of antibiotics prescribed in care homes or about the incidence and aetiology of AAD in this setting.

OBJECTIVES

The Probiotics for Antibiotic-Associated Diarrhoea (PAAD) study was designed as a two-stage study. PAAD stage 1 aimed to (1) prospectively describe antibiotic prescribing in care homes; (2) determine the incidence of C. difficile carriage and AAD (including C. difficile-associated diarrhoea); and (3) to consider implementation challenges and establish the basis for a sample size estimation for a randomised controlled trial (RCT) of probiotic administration with antibiotics to prevent AAD in care homes. If justified by PAAD stage 1, the RCT would be implemented in PAAD stage 2. However, as a result of new evidence regarding the clinical effectiveness of probiotics on the incidence of AAD, a decision was taken not to proceed with PAAD stage 2.

DESIGN

PAAD stage 1 was a prospective observational cohort study in care homes in South Wales with up to 12 months' follow-up for each resident.

SETTING

Recruited care homes had management and owner's agreement to participate and three or more staff willing to take responsibility for implementing the study.

PARTICIPANTS

Eleven care homes were recruited, but one withdrew before any residents were recruited. A total of 279 care home residents were recruited to the observational study and 19 withdrew, 16 (84%) because of moving to a non-participating care home.

MAIN OUTCOME MEASURES

The primary outcomes were the rate of antibiotic prescribing, incidence of AAD, defined as three or more loose stools (type 5-7 on the Bristol Stool Chart) in a 24-hour period, and C. difficile carriage confirmed on stool culture.

RESULTS

Stool samples were obtained at study entry from 81% of participating residents. Over half of the samples contained antibiotic-resistant isolates, with Enterobacteriaceae resistant to ciprofloxacin in 47%. Residents were prescribed an average of 2.16 antibiotic prescriptions per year [95% confidence interval (CI) 1.90 to 2.46]. Antibiotics were less likely to be prescribed to residents from dual-registered homes. The incidence of AAD was 0.57 (95% CI 0.41 to 0.81) episodes per year among those residents who were prescribed antibiotics. AAD was more likely in residents who were prescribed co-amoxiclav than other antibiotics and in those residents who routinely used incontinence pads. AAD was less common in residents from residential homes.

CONCLUSIONS

Care home residents, particularly in nursing homes, are frequently prescribed antibiotics and often experience AAD. Antibiotic resistance, including ciprofloxacin resistance, is common in Enterobacteriaceae isolated from the stool of care home residents. Co-amoxiclav is associated with greater risk of AAD than other commonly prescribed antibiotics.

TRIAL REGISTRATION

Current Controlled Trials ISRCTN 7954844.

FUNDING

This project was funded by the National Institute for Health Research (NIHR) Health Technology Assessment programme and will be published in full in Health Technology Assessment; Vol. 18, No. 63. See the NIHR Journals Library website for further project information.

Common infections in nursing homes: a review of current issues and challenges

Over 1.5 million people live in 16,000 nursing homes in the USA and experience an average of 2 million infections a year. Infections have been associated with high rates of morbidity and mortality, rehospitalization, extended hospital stay and substantial healthcare expenses. Emerging infections and antibiotic-resistant organisms in an institutional environment where there is substantial antimicrobial overuse and the population is older, frailer and sicker, create unique challenges for infection control. This review discusses the common infections, challenges, and a framework for a practical infection prevention program.