Impact of emergency hospital admissions on patterns of primary care prescribing: a retrospective cohort analysis of electronic records in England

Abstract

BackgroundLittle is known about the impact of hospitalisation on prescribing in UK clinical practice.AimTo investigate whether an emergency hospital admission drives increases in polypharmacy and potentially inappropriate prescriptions (PIPs).Design and settingA retrospective cohort analysis set in primary and secondary care in England.MethodChanges in number of prescriptions and PIPs following an emergency hospital admission in 2014 (at admission and 4 weeks post-discharge), and 6 months post-discharge were calculated among 37 761 adult patients. Regression models were used to investigate changes in prescribing following an admission.ResultsEmergency attendees surviving 6 months (N = 32 657) had a mean of 4.4 (standard deviation [SD] = 4.6) prescriptions before admission, and a mean of 4.7 (SD = 4.7; P<0.001) 4 weeks after discharge. Small increases (<0.5) in the number of prescriptions at 4 weeks were observed across most hospital specialties, except for surgery (−0.02; SD = 0.65) and cardiology (2.1; SD = 2.6). The amount of PIPs increased after hospitalisation; 4.0% of patients had ≥1 PIP immediately before pre-admission, increasing to 8.0% 4 weeks post-discharge. Across hospital specialties, increases in the proportion of patients with a PIP ranged from 2.1% in obstetrics and gynaecology to 8.0% in cardiology. Patients were, on average, prescribed fewer medicines at 6 months compared with 4 weeks post-discharge (mean = 4.1; SD = 4.6; P<0.001). PIPs decreased to 5.4% (n = 1751) of patients.ConclusionPerceptions that hospitalisation is a consistent factor driving rises in polypharmacy are unfounded. Increases in prescribing post-hospitalisation reflect appropriate clinical response to acute illness, whereas decreases are more likely in patients who are multimorbid, reflecting a focus on deprescribing and medicines optimisation in these individuals. Increases in PIPs remain a concern.