Trends and patterns in antibiotic prescribing among out-of-hours primary care providers in England, 2010–14

Abstract

Objectives

Antimicrobial resistance is a global threat, increasing morbidity and mortality. In England, publicly funded clinical commissioning groups (CCGs) commission out-of-hours (OOH) primary care services outside daytime hours. OOH consultations represent 1% of in-hours general practice (GP) consultations. Antibiotic prescriptions increased 32% in non-GP community services between 2010 and 2013. We describe OOH antibiotic prescribing patterns and trends between 2010 and 2014.

Methods

We: estimated the proportion of CCGs with OOH data available; described and compared antibiotic prescribing by volume of prescribed items, seasonality and trends in GP and OOH, using linear regression; and compared the proportion of broad-spectrum to total antibiotic prescriptions in OOHs with their respective CCGs in terms of seasonality and trends, using binomial regression.

Results

Data were available for 143 of 211 (68%) CCGs. OOH antibiotic prescription volume represented 4.5%–5.4% of GP prescription volume and was stable over time (P = 0.37). The proportion of broad-spectrum antibiotic prescriptions increased in OOH when it increased in the CCG they operated in (regression coefficient 0.98; 95% CI 0.96–0.99). Compared with GP, the proportion of broad-spectrum antibiotic prescriptions in OOH was higher but decreased both in GP and OOH (−0.57%, 95% CI − 0.54% to − 0.6% and −0.76%, 95% CI − 0.59% to − 0.93% per year, respectively).

Conclusions

OOH proportionally prescribed more antibiotics than GPs although we could not comment on prescribing appropriateness. OOH prescribing volume was stable over time, and followed GP seasonal patterns. OOH antibiotic prescribing reflected the CCGs they operated in but with relatively more broad-spectrum antibiotics than in-hours GP. Understanding factors influencing prescribing in OOH will enable the development of tailored interventions promoting optimal prescribing in this setting.

Introduction

Since 2004, the NHS has commissioned out-of-hours (OOH) services separately from in-hours (IH) primary care services. OOH primary care services provide urgent primary care when general practice (GP) surgeries are typically closed, from 6.30 pm to 8.00 am on weekdays and all day at weekends and on bank holidays.¹ From April 2013, NHS England delegated responsibility for commissioning such services to 211 clinical commissioning groups (CCGs). CCGs are independent statutory bodies governed by members of local GPs with support from health professionals and direct input from people representing patients and members of the public.² The OOH services are provided by social enterprises (49%), private companies (31%) and NHS Trusts (20%).¹ An estimated 10% of GPs have retained responsibility for OOH care; NHS England commissions these services (known as ‘opted-in’ services) directly from GP surgeries.¹ The contractual arrangements at CCG level are complex; of the 175 (83%) CCGs that responded to a recent National Audit Office survey, 105 were taking the lead in managing an OOH contract; some contracts (42%) covered several CCGs and other CCGs (6%) received services under more than one contract.¹

In 2013–14, OOH GP services in England handled ∼5.8 million cases, including 3.3 million face-to-face patient consultations, of which 800 000 were home visits. By comparison, IH GPs provide over 300 million consultations a year and 21.7 million people attend accident and emergency departments.¹

Antimicrobial resistance (AMR), linked to increased antibiotic use (both appropriate and inappropriate), is a growing threat to the effective treatment of an ever-increasing range of infections. The current lack of new antimicrobials on the horizon brings added urgency to the need to protect the efficacy of existing drugs. A post-antibiotic era, in which common infections and minor injuries can kill, is a very real possibility in the 21st century.³ In Europe, resistant infections in hospitals kill 25 000 people and cost €1.5 billion in extra hospital, treatment and societal costs every year.⁴ It is estimated that by 2050 AMR could be responsible for 10 million deaths globally and could cost up to US$100 trillion in lost output to the global economy.⁵ For these reasons, several strategies are being pursued to decrease the emergence of AMR, with antimicrobial stewardship, defined as ‘an organizational or healthcare-system-wide approach to promoting and monitoring judicious use of antimicrobials to preserve their future effectiveness’,⁶ a key intervention. Stewardship requires an understanding of the patterns of antibiotic utilization and resistance. In England, PHE has monitored these since 2014 through the English Surveillance Programme for Antimicrobial Utilization and Resistance (ESPAUR). The 2014 ESPAUR report noted a 32% increase in antibiotic prescriptions in community services other than GP between 2010 and 2013, in particular in community health services, hospital-based community services and urgent care settings. This highlights the need to explore whether GP prescribing is being displaced to other settings such as OOH primary care services.⁷ The little evidence available around antibiotic prescribing patterns in this specific setting suggests that OOH antibiotic prescribing is high⁸ and that, compared with patients’ own GPs, commercial companies providing OOH services prescribe more antibiotics.⁹ A study conducted in Oxfordshire, England showed an increase in the number of antibiotic prescriptions in OOH between 2010 and 2014, against a trend of a decreasing number of consultations.¹⁰ There is, however, no published description of the trends and patterns of antibiotic prescribing among OOH providers in England. We aimed to describe these between 2010 and 2014, to inform potential future stewardship interventions.

Methods

PHE obtains prescribing data for primary care from the NHS Business Services Authority¹¹ and merges this using NHS Digital classification of prescribing cost centres.¹² The merged database contains the number of prescribed antibiotic items each month, by antibiotic and by prescribing centre. We retained all GP and OOH prescribing centres excluding prescribing centres issuing <100 antibiotic items in a year. We calculated the proportion of CCGs with OOH data available in the ESPAUR database and estimated the volume of antibiotics these OOH providers prescribed and compared it with the prescription volume among GPs in CCGs with OOH data between 2010 and 2014. We described the overall prescribing volume among IH and OOH providers assessing for seasonality and calculated trends over time, using linear regression.

We further focused our comparative analysis of IH and OOH prescribing on broad-spectrum antibiotics, for two reasons: first, there is particular focus around broad-spectrum antibiotic stewardship as they can be used to treat a range of infections and their use can increase the risk of MRSA, Clostridium difficile and resistant urinary tract infections¹³ and their use in primary care should be restricted to situations when narrow-spectrum antibiotics are ineffective;¹⁴ and second, as no denominator data were available for OOH prescriptions that would allow comparison with IH prescribing, comparing the proportion of broad-spectrum antibiotics prescribed out of the total antibiotic prescription volume provided an element of direct comparison between OOH and IH providers. Cephalosporins, quinolones and co-amoxiclav were defined as broad spectrum, consistent with the England Department of Health Advisory Committee on Antimicrobial Resistance and Healthcare Associated Infection.¹⁵

The proportion of broad-spectrum to total antibiotic prescriptions in OOHs with their respective CCGs was compared using linear regression. We described and cross-correlated the seasonality of broad-spectrum antibiotic prescribing among OOH and GP providers, and compared the two in terms of trends in broad-spectrum antibiotic prescribing using binomial regression. All statistical analyses were done in STATA 13 (StataCorp, TX, USA).

Results

In 2014, data were available for 188 OOH providers, in 143 of 211 (68%) CCGs. Graphically, the distribution of CCGs with no OOH data seems to cluster in London and the South East, East Anglia and the Midlands (Figure 1), suggesting that CCGs in these areas may contract their OOH to NHS Trusts or to an OOH service from another CCG. These 188 OOH providers prescribed between 1 055 000 and 1 205 000 antibiotic items each year between 2010 and 2014 (Table 1). Between 2010 and 2013, this represented 5%–5.4% of the GP antibiotic prescription volume in those CCGs with OOH data, decreasing to 4.5% in 2014.

Figure 1.

CCGs in England, by availability of OOH prescribing data (2014).

Table 1.

Volume and proportion of antibiotic items prescribed in OOH settings, England, 2010–14

	Prescribed antibiotic items		Proportion of GP prescription volume prescribed in OOH (%)
Year	GPa	OOH
2010	21 029 000	1 055 000	5.0
2011	21 799 000	1 102 000	5.1
2012	22 228 000	1 205 000	5.4
2013	21 559 000	1 121 000	5.2
2014	26 239 000	1 170 000	4.5

^aIn CCGs with OOH data.

Prescription volume peaked each year in December and was at its lowest each year in July for both GP and OOH (Figure 2). There were no statistically significant changes in the overall number of items prescribed yearly in either GP or OOH over the study period (P = 0.37). OOH broad-spectrum antibiotic prescribing increased with CCG prescribing; the higher the broad-spectrum prescribing in the CCG, the higher the broad-spectrum prescribing in OOH (Figure 3; regression coefficient 0.98, 95% CI 0.96–0.99).

Figure 2.

Total number of antibiotic items prescribed, by type of provider and month, England, 2010–14. Please note that the vertical axis scale is different for GPs and OOH.

Figure 3.

Contribution of broad-spectrum antibiotics to prescribing volume among OOH providers and their CCGs, England, 2010–14.

The relative contribution of broad-spectrum antibiotics to total prescription volume was highest each year in July both among GPs and OOH. Broad-spectrum prescribing in OOH correlated with GP prescribing in terms of trends and seasonality (Figure 4; cross-correlation coefficient = 0.95). Compared with GPs, the contribution of broad-spectrum antibiotics to total antibiotic prescribing in OOH was consistently higher (Table 2; P < 0.001 each year). However, this contribution was decreasing both among GPs (−0.57% per year on average, 95% CI −0.54% to −0.6%) and to an even greater extent OOH (–0.76% per year on average, 95% CI −0.59% to −0.93%).

Figure 4.

Contribution of broad-spectrum antibiotics to prescribing volume among OOH providers and GPs, by month, England, 2010–14.

Table 2.

Proportion of broad-spectrum antibiotics of total antibiotic prescriptions, by year and type of practice, England, 2010–14

Type of practice	Year
	2010	2011	2012	2013	2014
GP	12.7 (12.5–12.8)	11.8 (11.7–11.9)	10.7 (10.7–10.8)	10.6 (10.5–10.7)	10.3 (10.3–10.4)
OOH	15.5 (14.9–16)	14.8 (14.3–15.3)	13.4 (12.9–13.9)	13.0 (12.4–13.5)	12.5 (12–13.1)

Values shown are percentages (95% CI).

Discussion

This study is, to our knowledge, the first to focus specifically on national level prescribing in the primary care OOH setting in England. OOH consultations represent ∼1% of the volume of IH GP consultations, but up to 5% of the volume of antibiotic prescriptions. Compared with IH GP, OOH antibiotic prescribing was out of proportion to the volume of consultations, suggesting that more OOH consultations are related to acute infection presentations, a finding consistent with the published literature.¹⁶ The disproportionality reduced in 2014 compared with previous years, mainly due to increased coding of IH prescription volume between 2013 and 2014; while this may reflect a true difference in focus, it may also reflect increased IH practices taking on OOH workload at the same practice code. OOH prescribing volume was stable over time, and followed seasonal patterns similar to IH GP prescriptions; with traditional increases in prescribing in the winter months, related to increased prevalence of respiratory tract infections. The relative contribution of broad-spectrum antibiotics was consistently higher among OOH providers compared with GP providers over this period, although that proportion was decreasing in both settings, and decreasing faster in OOH settings, narrowing the gap between the two. Qualitative work is required to understand the factors that drive broad-spectrum prescribing in OOH care; to our knowledge there is no published literature on factors contributing to increased likelihood of prescribing antibiotics in OOH settings.

It is possible that increased awareness of AMR as a global issue among healthcare professionals, reinforced by several high-profile publications including a Chief Medical Officer report focused on AMR,⁶ combined with specific prescribing guidance on reducing broad-spectrum antibiotic prescribing in primary care^13,14 and primary-care-focused antibiotic stewardship programmes¹⁷ have contributed to this decrease in broad-spectrum antibiotic prescribing.

This study offers new insights into OOH prescribing. However, limitations to the data and organizational features of OOH services have limited the scope of the analysis. First, OOH prescribing data were linked geographically to two-thirds of CCGs. However, increasingly, the same OOH provider covers several CCGs and some CCGs commission more than one provider; it was therefore not possible to estimate the size of the population covered by each OOH provider or calculate prescription volume by population to compare with GP prescription. We were not able to ascertain the representativeness of our sample because of the heterogeneous nature of OOH providers, rapid turnover of OOH providers and no reliable data on who provides OOH services where. For these reasons we analysed the data at a national level and did not perform a multi-level analysis including CCGs as a random variable. Finally, clinical indications for prescriptions were not available, making it difficult to ascertain appropriateness of prescriptions; it is plausible that a higher proportion of OOH consultations are for acute conditions including infections. Similarly, broad-spectrum antibiotic prescribing may reflect illness spectrum or failure of first-line treatments.

This study provides a first insight into antibiotic prescribing among OOH providers. It highlights that compared with GP, antibiotic prescribing, both overall and in terms of broad-spectrum antibiotics, is more common. Little is known about the appropriateness of this prescribing, and our data did not allow evaluation of the appropriateness of OOH prescribing due to lack of information on the spectrum of illness presenting OOH. This setting therefore warrants further attention with regards to antibiotic stewardship. Understanding the factors driving prescribing behaviour among OOH practitioners and how they relate to presenting complaints will help inform tailored interventions to promote prudent antibiotic use in this setting.