Betina Blak

The importance of defining periods of complete mortality reporting for research using automated data from primary care

To define periods of acceptable mortality reporting in primary care and to demonstrate through examples the implication for research using automated medical data.

Use of demographic and pharmacy data to identify patients included within both the Clinical Practice Research Datalink (CPRD) and The Health Improvement Network (THIN)

Pharmacoepidemiology researchers often utilize data from two UK electronic medical record databases, the Clinical Practice Research Datalink (CPRD) and The Health Improvement Network (THIN), and may choose to combine the two in an effort to increase sample size. To minimize duplication of data, previous studies examined the practice‐level overlap between these databases. However, the proportion of overlapping patients remains unknown. We developed a method using demographic and pharmacy variables to identify patients included in both CPRD and THIN, and applied this method to measure the proportion of overlapping patients who initiated the oral anti‐diabetic drug saxagliptin.

Drug treatment patterns for the management of men with lower urinary tract symptoms associated with benign prostatic hyperplasia who have both storage and voiding symptoms: a study using the health improvement network UK primary care data

Abstract Background: Real-world data on the pharmacological management of men who have lower urinary tract symptoms (LUTS) associated with benign prostatic hyperplasia (BPH) are limited. Objective: To characterize men with LUTS/BPH who had both storage and voiding symptoms and to evaluate treatment patterns in UK primary care. Design, setting and participants: This was an observational study of men aged ≥45 years with a diagnosis, symptoms or therapies indicative of LUTS/BPH with both storage and voiding components. These men were identified from the large Health Improvement Network (THIN) database between 1 January 2004 and 30 September 2011. Outcome measurements and statistical analysis: Drug prescriptions and switching/discontinuation patterns for α1-blockers and antimuscarinics. Results and limitations: We identified 8694 men with a median age of 66.0 (interquartile range [IQR], 59.0–74.0) years. Most (7850; 90.3%) received an α1-blocker, and 2167 (24.9%) received antimuscarinic therapy over a median of 2.1 years. The most commonly prescribed α1-blocker was tamsulosin (81.8%); most frequent antimuscarinics were tolterodine (41.0%), oxybutynin (37.2%) and solifenacin (35.7%). Concomitant prescription of α1-blocker and antimuscarinic therapy (within 30 days of each other) was received by 1160 men (14.8% of α1-blocker-treated men). Of α1-blocker recipients, 3024 (38.5%) discontinued during follow-up, while 1149 (53.0%) discontinued antimuscarinic therapy. Of 2167 men who received an antimuscarinic, 476 (22.0%) switched to another antimuscarinic. Of the three most commonly prescribed antimuscarinics, solifenacin had the lowest proportions of discontinuations (43.0%) and switches (15.3%), and the longest median duration of therapy (90 days, IQR 30–300). General practice consultations accounted for most resource use (5307.9 per 1000 patient-years). Conclusions: This study presents real-world management of men with LUTS/BPH who have both storage and voiding symptoms. The low proportion of men who received concomitant α1-blocker and antimuscarinic therapy suggests that some patients are sub-optimally treated in routine clinical practice.

Uptake of childhood influenza vaccine from 2012–2013 to 2014–2015 in the UK and the implications for high-risk children: a retrospective observational cohort study

Objectives To evaluate changes in influenza vaccination rates in healthy and at-risk children following the implementation of the UKs childhood influenza immunisation programme. Design Observational cohort study before and after initiation of the UKs childhood influenza immunisation programme over three influenza seasons (2012–2013, 2013–2014 and 2014–2015) using data from the Clinical Practice Research Datalink (CPRD). Setting More than 500 primary care practices in the UK. Population All individuals aged 2–17 years on 1 September, with at least 12 months of medical history documented in CPRD were retained in the analysis. Intervention Starting in 2013–2014, all children aged 2 and 3 years were offered influenza vaccination through general practice, and primary school-aged children were offered influenza vaccination in selected counties in England (described as pilot regions). The vaccination programme was extended to all children aged 4 years in England in 2014–2015. Main outcome measure Cumulative vaccination rate from 1 September to 28 February of the next calendar year as assessed by a time-to-event statistical model (vaccination uptake). Age group, sex, region and type of high-risk medical condition were assessed as predictors. Results Vaccination uptake increased considerably from 2012–2013 to 2013–2014 in targeted children aged 2–3 years, both in children with a high-risk medical condition (from 40.7% to 61.1%) and those without (from 1.0% to 43.0%). Vaccination rates increased also, though less markedly, in older children. In 2014–2015, vaccination rates remained higher than 40% in healthy children aged 2–3 years, although they decreased slightly from 2013–2014 (from 43.0% to 41.8%). Vaccination rates in older healthy children continued to increase, driven primarily by an increase in children aged 4 years to 31.3% in 2014–2015. Conclusions The introduction of a universal childhood vaccination policy in the UK increased vaccination rates for targeted children, including those with high-risk conditions.

Dapagliflozin therapy for type 2 diabetes in primary care: Changes in HbA1c, weight and blood pressure over 2 years follow-up

AIMS To investigate prescribing patterns and effect of dapagliflozin among individuals with T2DM using UK primary care data. METHODS Adult patients with T2DM initiating dapagliflozin treatment were identified from the Clinical Practice Research Datalink. Changes in HbA1c, body weight and systolic blood pressure were assessed in subgroups defined by glucose lowering treatment at baseline and compliance with the Summary of Product Characteristics. Logistic regression examined the association of baseline characteristics with achievement of target HbA1c (≤53mmol/mol) and weight reduction (by ≥3.0%). RESULTS Among 5828 eligible individuals, HbA1c was reduced from a baseline mean of 80.0mmol/mol (SD 17.6) by -12.8 (95% CI -13.8, -11.8)mmol/mol at >12-24 months. The corresponding value for weight reduction (baseline mean 101.7kg) was -5.0 (-5.4, -4.5)kg, and for systolic blood pressure reduction (baseline mean 134.1mmHg) was -3.1 (-4.0, -2.2) mmHg. Lower baseline HbA1c values (<69; 69-85 versus ≥86mmol/mol) were positively associated with achievement of target HbA1c <53mmol/mol. CONCLUSIONS Treatment with dapagliflozin in T2DM was associated with reductions in HbA1c, weight and systolic blood pressure over time periods up to 2 years. Changes in these parameters were consistent with those reported in RCTs.

Weight change and healthcare resource use in English patients with type 2 diabetes mellitus initiating a new diabetes medication class

The aim of this study was to investigate the association between weight change and healthcare resource use (HCRU) and costs in English primary care patients with type 2 diabetes mellitus (T2DM) initiating treatment with a new diabetes medication class.

Topical prostaglandin fixed combinations in UK primary care: observational study using data from the health improvement network

Purpose To describe the use of 3 prostaglandin/timolol fixed combinations (FCs) in UK primary care, to summarize characteristics of recipients, and to assess 12-month persistence. Methods This retrospective cohort study included first-time recipients of latanoprost/timolol FC, bimatoprost/timolol FC, or travoprost/timolol FC treated between April 1, 2007, and November 30, 2008, identified in The Health Improvement Network database, a large database of anonymized longitudinal electronic medical records of patients treated in UK primary care. Eligible patients were ≥18 years old at the index date (date of first prescription). Persistence, defined as a gap ≤60 days between consecutive prescriptions, was assessed through 12 months post-index for each cohort (Cox proportional hazards models). Results A total of 2,015 patients were included: latanoprost/timolol FC, n=898 (44.6%); bimatoprost/timolol FC, n=733 (36.4%); travoprost/timolol FC, n=384 (19.1%). The mean age was approximately 72 years across cohorts (p=0.792). Glaucoma was the diagnosis for >90% of patients in each cohort. Twelve-month persistence was similar across treatments: latanoprost/timolol FC: 38.2%; bimatoprost/timolol FC: 38.6%; travoprost/timolol FC: 38.3% (p=0.985). Mean time to therapy change for nonpersistent patients was also similar: 143.3±89.8, 151.0±87.9, and 151.8±87.7 days, respectively (p=0.095). Among persistent patients, additional therapy was prescribed for 36.2%, 41.7%, and 41.5% of patients, respectively. Among nonpersistent patients, 64.0%, 70.4%, and 69.2%, respectively, restarted the index therapy. Conclusions The largest proportion of first-time recipients of prostaglandin/beta-blocker FC products treated in UK primary care was prescribed latanoprost/timolol FC. Twelve-month persistence was similar (<40%) across the 3 FCs evaluated.

A retrospective observational analysis of post-pandemic influenza-related outcomes in the United Kingdom, 2010–2014

ABSTRACT This study set out to evaluate influenza- and respiratory-related illnesses recorded during primary care physician consultations in England following the H1N1 pandemic in 2009 and to enable the development of a dynamic disease model. Data were obtained from the Clinical Practice Research Datalink of primary care records over four influenza seasons (2010–2014). The primary outcome of the study was incidence of influenza- and respiratory-related diagnoses, calculated per practice and by season and age group. Upper respiratory tract infection diagnoses were most frequently recorded (mean seasonal practice level incidence; 3,762 consultations per 100,000 [SD = 1,989]), and influenza-related diagnoses were least frequently recorded across all seasons, except one. Incidence rates for the under 18 population were higher than those for the general population, in particular for upper respiratory tract infection (range of 8,024–9,950 versus 3,228–4,120, respectively) and otitis media diagnoses (2,668–3,652 versus 782–1,057, respectively). For influenza-related diagnoses, the 65+ age group, the 0 to <2 and 2 to <4 groups had a higher risk (risk ratio = 1.33, 1.12 and 1.16, respectively) than other age groups. This study provides valuable insight into the incidence of influenza- and respiratory-related diagnoses in the primary care setting in England, and suggests a higher burden of disease in young children and the elderly. The study also indicates that some influenza illness is likely to be reported under respiratory-related diagnoses, given the low incidence of influenza-related diagnoses in the study.

Impact of increased influenza vaccination in 2–3-year-old children on disease burden within the general population: A Bayesian model-based approach

Introduction During the 2013–2014 influenza season, Public Health England extended routine influenza vaccination to all 2- and 3-year-old children in England. To estimate the impact of this change in policy on influenza-related morbidity and mortality, we developed a disease transmission and surveillance model informed by real-world data. Methods We combined real-world and literature data sources to construct a model of influenza transmission and surveillance in England. Data were obtained for four influenza seasons, starting with the 2010–2011 season. Bayesian inference was used to estimate model parameters on a season-by-season basis to assess the impact of targeting 2- and 3-year-old children for influenza vaccination. This provided the basis for the construction of counterfactual scenarios comparing vaccination rates of ~2% and ~35% in the 2- and 3- year-old population to estimate reductions in general practitioner (GP) influenza-like-illness (ILI) consultations, respiratory hospitalizations and deaths in the overall population. Results Our model was able to replicate the main patterns of influenza across the four seasons as observed through laboratory surveillance data. Targeting 2- and 3-year-old children for influenza vaccination resulted in reductions in the general population of between 6.2–9.9% in influenza-attributable GP ILI consultations, 6.1–10.7% in influenza-attributable respiratory hospitalizations, and 5.7–9.4% in influenza-attributable deaths. The decrease in influenza-attributable ILI consultations represents a reduction of between 4.5% and 7.3% across all ILI consultations. The reduction in influenza-attributable respiratory hospitalizations represents a reduction of between 1.2% and 2.3% across all respiratory hospitalizations. Reductions in influenza-attributable respiratory deaths represent a reduction of between 0.9% and 2.4% in overall respiratory deaths. Conclusion This study has provided evidence that extending routine influenza vaccination to all healthy children aged 2 and 3 years old leads to benefits in terms of reduced utilization of healthcare resources and fewer respiratory health outcomes and deaths.