ObjectiveTo determine if trimethoprim use for urinary tract infection (UTI) is associated with an increased risk of acute kidney injury, hyperkalaemia, or sudden death in the general population.DesignCohort study.SettingUK electronic primary care records from practices contributing to the Clinical Practice Research Datalink linked to the Hospital Episode Statistics database.ParticipantsAdults aged 65 and over with a prescription for trimethoprim, amoxicillin, cefalexin, ciprofloxacin, or nitrofurantoin prescribed up to three days after a primary care diagnosis of UTI between April 1997 and September 2015.Main outcome measuresThe outcomes were acute kidney injury, hyperkalaemia, and death within 14 days of a UTI treated with antibiotics.ResultsAmong a cohort of 1 191 905 patients aged 65 and over, 178 238 individuals were identified with at least one UTI treated with antibiotics, comprising a total of 422 514 episodes of UTIs treated with antibiotics. The odds of acute kidney injury in the 14 days following antibiotic initiation were higher following trimethoprim (adjusted odds ratio 1.72, 95% confidence interval 1.31 to 2.24) and ciprofloxacin (1.48, 1.03 to 2.13) compared with amoxicillin. The odds of hyperkalaemia in the 14 days following antibiotic initiation were only higher following trimethoprim (2.27, 1.49 to 3.45) compared with amoxicillin. However, the odds of death within the 14 days following antibiotic initiation were not higher with trimethoprim than with amoxicillin: in the whole population the adjusted odds ratio was 0.90 (95% confidence interval 0.76 to 1.07) while among users of renin-angiotensin system blockers the odds of death within 14 days of antibiotic initiation was 1.12 (0.80 to 1.57). The results suggest that, for 1000 UTIs treated with antibiotics among people 65 and over, treatment with trimethoprim instead of amoxicillin would result in one to two additional cases of hyperkalaemia and two admissions with acute kidney injury, regardless of renin-angiotensin system blockade. However, for people taking renin-angiotensin system blockers and spironolactone treatment with trimethoprim instead of amoxicillin there were 18 additional cases of hyperkalaemia and 11 admissions with acute kidney injury.ConclusionTrimethoprim is associated with a greater risk of acute kidney injury and hyperkalaemia compared with other antibiotics used to treat UTIs, but not a greater risk of death. The relative risk increase is similar across population groups, but the higher baseline risk among those taking renin-angiotensin system blockers and potassium-sparing diuretics translates into higher absolute risks of acute kidney injury and hyperkalaemia in these groups.

Purpose The Clinical Practice Research Datalink (CPRD) now provides a new medical record database, CPRD Aurum. This is the first of several studies being undertaken to assess the quality and completeness of CPRD Aurum data for research endeavors. Methods We identified patients with a pulmonary embolism (PE) diagnosis from a random sample of 50 000 patients in CPRD Aurum and compared the diagnoses using data from Hospital Episode Statistics (HES). We calculated the proportion of PE cases recorded in CPRD Aurum who also had a PE diagnosis recorded in HES. We also evaluated completeness by identifying all PE diagnoses in HES and calculating the proportion also present in CPRD Aurum. Results The study included 781 PE patients: 580 had a PE in CPRD Aurum, 632 had a PE in HES, and 431 had a PE in both. The proportion of patients with anticoagulated PE in CPRD Aurum confirmed by HES was 76.8%. The completeness of primary hospitalized PE HES events compared to CPRD Aurum was 79.1%. In most instances, there was a plausible explanation for the presence of a PE in only one of the two data sources. Conclusions The results of this study are reassuring and suggest that the correctness (eg, quality, accuracy) and completeness of diagnosis information in CPRD Aurum are promising with respect to serious acute conditions that require medical attention. Evaluation of other data elements will provide additional insight into this new data resource and its utility for medical research.

Pharmacovigilance can be defined as the science of monitoring medicines and vaccines after license for use, the purpose of which is to quantify and characterise the safety profile of a medicine, identify previously unknown adverse reactions, inform risk-benefit assessment, and support the development of actions that can be taken to reduce risks, optimise benefits and monitor their effectiveness. This review discusses the Clinical Practice Research Datalink (CPRD), which is the source of the largest research database in the UK with longitudinal, representative primary care data linked to data from other healthcare settings. CPRD supports international pharmacovigilance by providing a large, anonymised representative general population database with comprehensive capture of patient risk factors and outcomes to researchers within academic, regulatory and pharmaceutical organisations. The specific advantages of CPRD data are discussed in the context of the ‘six Vs of big data’ including volume, velocity, variety, veracity, validity and value. Examples of where CPRD data have been used for pharmacovigilance research and how these have fed into guidelines and policy are discussed.

IntroductionHealth and care data are routinely collected about care home residents in England, yet there is no way to collate these data to inform benchmarking and improvement. The Developing research resources And minimum data set for Care Homes’ Adoption and use study has developed a prototype minimum data set (MDS) for piloting.Methods and analysisA mixed-methods longitudinal pilot study will be conducted in 60 care homes (approximately 960 residents) in 3 regions of England, using resident data from cloud-based digital care home records at two-time points. These will be linked to resident and care home level data held within routine National Health Service and social care data sets. Two rounds of focus groups with care home staff (n=8–10 per region) and additional interviews with external stakeholders (n=3 per region) will explore implementation and the perceived utility of the MDS. Data will be assessed for completeness and timeliness of completion. Descriptive statistics, including percentage floor and ceiling effects, will establish data quality. For validated scales, construct validity will be assessed by hypothesis testing and exploratory factor analysis will establish structural validity. Internal consistency will be established using Cronbach’s alpha. Longitudinal analysis of the pilot data will demonstrate the value of the MDS to each region. Qualitative data will be analysed inductively using thematic analysis to understand the complexities of implementing an MDS in care homes for older people.Ethics and disseminationThe study has received ethical approval from the London Queen’s Square Research Ethics Committee (22/LO/0250). Informed consent is required for participation. Findings will be disseminated to: academics working on data use and integration in social care, care sector organisations, policy makers and commissioners. Findings will be published in peer-reviewed journals. Partner NIHR Applied Research Collaborations, the National Care Forum and the British Geriatrics Society will disseminate policy briefs.