Coding infections in primary care

Within-episode repeat antibiotic prescriptions in patients with respiratory tract infections: A population-based cohort study

BACKGROUND

Antimicrobial stewardship interventions mainly focus on initial antibiotic prescriptions, with few considering within-episode repeat prescriptions. We aimed to describe the magnitude, type and determinants of within-episode repeat antibiotic prescriptions in patients presenting to primary care with respiratory tract infections (RTIs).

METHODS

We conducted a population-based cohort study among 530 sampled English general practices within the Clinical Practice Research Datalink (CPRD). All individuals with a primary care RTI consultation for which an antibiotic was prescribed between March 2018 and February 2022. Main outcome measurement was repeat antibiotic prescriptions within 28 days of a RTI visit stratified by age (children vs. adults) and RTI type (lower vs. upper RTI). Multivariable logistic regression and principal components analyses were used to identify risk factors and patient clusters at risk for within-episode repeat prescriptions.

FINDINGS

905,964 RTI episodes with at least one antibiotic prescription were identified. In adults, 19.9% (95% CI 19.3-20.5%) had at least one within-episode repeat prescription for a lower RTI, compared to 10.5% (95% CI 10.3-10.8%) for an upper RTI. In children, this was around 10% irrespective of RTI type. The majority of repeat prescriptions occurred a median of 10 days after the initial prescription and was the same antibiotic class in 48.3% of cases. Frequent RTI related GP visits and prior within-RTI-episode repeat antibiotic prescriptions were main factors associated with repeat prescriptions in both adults and children irrespective of RTI type. Young (<2 years) and older (65+) age were associated with repeat prescriptions. Among those aged 2-64 years, allergic rhinitis, COPD and oral corticosteroids were associated with repeat prescriptions.

INTERPRETATIONS

Repeat within-episode antibiotic use accounts for a significant proportion of all antibiotics prescribed for RTIs, with same class antibiotics unlikely to confer clinical benefit and is therefore a prime target for future antimicrobial stewardship interventions.

Electronic Health Records and Antimicrobial Stewardship Research: a Narrative Review

Purpose of Review

This review summarises epidemiological research using electronic health records (EHR) for antimicrobial stewardship.

Recent Findings

EHRs enable surveillance of antibiotic utilisation and infection consultations. Prescribing for respiratory tract infections has declined in the UK following reduced consultation rates. Reductions in prescribing for skin and urinary tract infections have been less marked. Drug selection has improved and use of broad-spectrum antimicrobics reduced. Diagnoses of pneumonia, sepsis and bacterial endocarditis have increased in primary care. Analytical studies have quantified risks of serious bacterial infections following reduced antibiotic prescribing. EHRs are increasingly used in interventional studies including point-of-care trials and cluster randomised trials of quality improvement. Analytical and interventional studies indicate patient groups for whom antibiotic utilisation may be more safely reduced.

Summary

EHRs offer opportunities for surveillance and interventions that engage practitioners in the effects of improved prescribing practices, with the potential for better outcomes with targeted study designs.

Safety of reducing antibiotic prescribing in primary care: a mixed-methods study

Background

The threat of antimicrobial resistance has led to intensified efforts to reduce antibiotic utilisation, but serious bacterial infections are increasing in frequency.

Objectives

To estimate the risks of serious bacterial infections in association with lower antibiotic prescribing and understand stakeholder views with respect to safe antibiotic reduction.

Design

Mixed-methods research was undertaken, including a qualitative interview study of patient and prescriber views that informed a cohort study and a decision-analytic model, using primary care electronic health records. These three work packages were used to design an application (app) for primary care prescribers.

Data sources

The Clinical Practice Research Datalink.

Setting

This took place in UK general practices.

Participants

A total of 706 general practices with 66.2 million person-years of follow-up from 2002 to 2017 and antibiotic utilisation evaluated for 671,830 registered patients. The qualitative study included 31 patients and 30 health-care professionals from primary care.

Main outcome measures

Sepsis and localised bacterial infections.

Results

Patients were concerned about antimicrobial resistance and the side effects, as well as the benefits, of antibiotic treatment. Prescribers viewed the onset of sepsis as the most concerning potential outcome of reduced antibiotic prescribing. More than 40% of antibiotic prescriptions in primary care had no coded indication recorded across both Vision® and EMIS® practice systems. Antibiotic prescribing rates varied widely between general practices, but there was no evidence that serious bacterial infections were less frequent at higher prescribing practices (adjusted rate ratio for 20% increase in prescribing 1.03, 95% confidence interval 1.00 to 1.06; p = 0.074). The probability of sepsis was lower if an antibiotic was prescribed at an infection consultation, and the number of antibiotic prescriptions required to prevent one episode of sepsis (i.e. the number needed to treat) decreased with age. For those aged 0–4 years, the number needed to treat was 29,773 (95% uncertainty interval 18,458 to 71,091) in boys and 27,014 (95% uncertainty interval 16,739 to 65,709) in girls. For those aged > 85 years, the number needed to treat was 262 (95% uncertainty interval 236 to 293) in men and 385 (95% uncertainty interval 352 to 421) in women. Frailty was associated with a greater risk of sepsis and a smaller number needed to treat. For severely frail patients aged 55–64 years, the number needed to treat was 247 (95% uncertainty interval 156 to 459) for men and 343 (95% uncertainty interval 234 to 556) for women. At all ages, the probability of sepsis was greatest for urinary tract infection, followed by skin infection and respiratory tract infection. The numbers needed to treat were generally smaller for the period 2014–17, when sepsis was diagnosed more frequently. The results are available using an app that we developed to provide primary care prescribers with stratified risk estimates during infection consultations.

Limitations

Analyses were based on non-randomised comparisons. Infection episodes and antibiotic prescribing are poorly documented in primary care.

Conclusions

Antibiotic treatment is generally associated with lower risks, but the most serious bacterial infections remain infrequent even without antibiotic treatment. This research identifies risk strata in which antibiotic prescribing can be more safely reduced.

Future work

The software developed from this research may be further developed and investigated for antimicrobial stewardship effect.

Funding

This project was funded by the National Institute for Health Research (NIHR) Health Services and Delivery Research programme and will be published in full in Health Services and Delivery Research; Vol. 9, No. 9. See the NIHR Journals Library website for further project information.