Validation of diabetic retinopathy and maculopathy diagnoses recorded in a U.K. primary care database

Initiation of antidepressant medication in people with type 2 diabetes living in the UK - a retrospective cohort study

Introduction

Depression is a common comorbidity in people with type 2 diabetes and it is associated with poorer outcomes. There is limited data on the treatments used for depression in this population. The aim of this study was to explore the rates of initiation of antidepressant prescriptions in people with type 2 diabetes in the UK and identify those most at risk of needing such treatment.

Research Design and Methods

This was a retrospective cohort study using data from IQVIA Medical Research Data (IMRD)‐UK data. Data from general practices in IMRD‐UK between January 2008 and December 2017 were used for this study.

Results

The overall rates of antidepressant prescribing were stable over the study period. The rate of initiation of antidepressant medication in people with type 2 diabetes was 22.93 per 1000 person years at risk (PYAR) with a 95%CI 22.48 to 23.39 compared to 16.89 per 1000 PYAR (95%CI 16.77 to 17.01) in an age and gender matched cohort. The risk of being prescribed antidepressant medication with age had a U‐shaped distribution with the lowest risk in the 65–69 age group. The peak age for antidepressant initiation in men and women was 40–44, with a rate in men of 32.78 per 1000 PYAR (95% CI 29.57 to 36.34) and a rate in women of 46.80 per 1000 PYAR (95% CI 41.90 to 52.26). People with type 2 diabetes with in the least deprived quintile had an initiation rate of 19.66 per 1000 PYAR (95%CI 18.67 to 20.70) compared to 27.19 per 1000 PYAR (95%CI 25.50 to 28.93) in the most deprived quintile, with a 32% increase in the risk of starting antidepressant medication (95%CI 1.22 to 1.43).

Conclusions

People with type 2 diabetes were 30% more likely to be started on antidepressant medication than people without type 2 diabetes. Women with type 2 diabetes were 35% more likely than men to be prescribed antidepressants and the risks increased with deprivation and in younger or older adults, with the lowest rates in the 65–69 year age band. The rates of antidepressant prescribing were broadly stable over the 10‐year period in this study. The antidepressant medications prescribed changed slightly over time with sertraline becoming more widely used and fewer prescriptions of citalopram.

Long term miscarriage-related hypertension and diabetes mellitus. Evidence from a United Kingdom population-based cohort study

BACKGROUND

Miscarriages affect up to a fifth of all pregnancies and are associated with substantial psychological morbidity. However, their relationship with cardiometabolic risk factors is not well known. Therefore, in this study we aimed to estimate the burden of cardiovascular risk factors including diabetes mellitus (type 1 or 2) and hypertension in women with miscarriage compared to women without a record of miscarriage.

METHODS

A population-based retrospective cohort study was conducted using IVQIA Medical Research Data UK (IMRD-UK) between January 1995 and May 2016, an anonymised electronic health records database that is representative of the UK population. A total of 86,509, 16-50-year-old women with a record of miscarriage (exposed group) were matched by age, smoking status, and body mass index to 329,865 women without a record of miscarriage (unexposed group). Patients with pre-existing hypertension and diabetes were excluded. Adjusted incidence rate ratios (aIRR) and 95% confidence intervals (95% CI) for diabetes and hypertension were estimated using multivariable Poisson regression models offsetting for person-years follow-up.

RESULTS

The mean age at cohort entry was 31 years and median follow up was 4.6 (IQR 1.7-9.4) years. During the study period, a total of 792 (IR 1.44 per 1000 years) and 2525 (IR 1.26 per 1000 years) patients developed diabetes in the exposed and unexposed groups, respectively. For hypertension, 1995 (IR 3.73 per 1000 years) and 1605 (IR 3.39 per 1000 years) new diagnoses were recorded in the exposed and unexposed groups, respectively. Compared to unexposed individuals, women with a record miscarriage were more likely to develop diabetes (aIRR = 1.25, 95% CI: 1.15-1.36; p<0.001) and hypertension (aIRR = 1.07, 95% CI: 1.02-1.12; p = 0.005).

CONCLUSIONS

Women diagnosed with miscarriage were at increased risk of developing diabetes mellitus and hypertension. Women with history of miscarriage may benefit from periodic monitoring of their cardiometabolic health.

Disease burden of diabetes, diabetic retinopathy and their future projections in the UK: cross-sectional analyses of a primary care database

OBJECTIVES

To estimate the current disease burden, trends and future projections for diabetes mellitus (DM) and diabetic retinopathy (DR) in the IQVIA Medical Research Data (IMRD).

PARTICIPANTS/DESIGN/SETTING

We performed a cross-sectional study of patients aged 12 and above to determine the prevalence of DM and DR from the IMRD database (primary care database) in January 2017, involving a total population of 1 80 824 patients with DM. We also carried out a series of cross-sectional studies to investigate prevalence trends, and then applied a double exponential smoothing model to forecast the future burden of DM and DR in the UK.

RESULTS

The crude DM prevalence in 2017 was 5.2%. The DR, sight-threatening retinopathy (STR) and diabetic maculopathy prevalence figures in 2017 were 33.78%, 12.28% and 7.86%, respectively, in our IMRD cross-sectional study. There were upward trends in the prevalence of DM, DR and STR, most marked and accelerating in STR in type 1 DM but slowing in type 2 DM, and in the overall prevalence of DR.

CONCLUSION

Our results suggest differential rising trends in the prevalence of DM and DR. Preventive strategies, as well as treatment services planning, can be based on these projected prevalence estimates. Improvements that are necessary for the optimisation of care pathways, and preparations to meet demand and capacity challenges, can also be based on this information. The limitations of the study can be overcome by a future collaborative study linking DR screening and hospital eye services data.

Diabetic Retinopathy Screening and Registration in Europe-Narrative Review

Diabetic retinopathy (DR) is a leading cause of preventable vision impairment and blindness in the European Region. Despite the fact that almost all European countries have some kind of prophylactic eye examination for people with diabetes, the examinations are not properly arranged and are not organized according to the principles of screening in medicine. In 2021, the current COVID-19 pandemic moved telemedicine to the forefront healthcare services. Due to that, a lot more patients could benefit from comfortable and faster access to ophthalmology specialist care. This study aimed to conduct a narrative literature review on current DR screening programs and registries in the European Union for the last 20 years. With the implementation of telemedicine in daily medical practice, performing screening programs became much more attainable. Remote assessment of retinal pictures simultaneously saves countries time, money, and other resources.

Time trends in the incidence of clinically diagnosed type 2 diabetes and pre-diabetes in the UK 2009-2018: a retrospective cohort study

INTRODUCTION

To describe recent trends in the incidence of clinically diagnosed type 2 diabetes and pre-diabetes in people seen in UK general practice.

RESEARCH DESIGN AND METHODS

A retrospective cohort study using IQVIA Medical Research Data looking at people newly diagnosed with type 2 diabetes and pre-diabetes through primary care registers in the UK between 1 January 2009 and 31 December 2018.

RESULTS

A cohort of 426 717 people were clinically diagnosed with type 2 diabetes and 418 656 people met the criteria for a diagnosis of pre-diabetes in that time period. The incidence of clinically diagnosed type 2 diabetes per 1000 person years at risk (PYAR) in men decreased from a peak of 5.06 per 1000 PYAR (95% CI 4.97 to 5.15) in 2013 to 3.56 per 1000 PYAR (95% CI 3.46 to 3.66) by 2018. For women, the incidence of clinically diagnosed type 2 diabetes per 1000 PYAR decreased from 4.45 (95% CI 4.37 to 4.54) in 2013 to 2.85 (2.76 to 2.93) in 2018. The incidence rate of pre-diabetes tripled by the end of the same study period in men and women.

CONCLUSIONS

Between 2009 and 2018, the incidence rate of new clinical diagnoses of type 2 diabetes recorded in a UK primary care database decreased by a third from its peak in 2013-2014, while the incidence of pre-diabetes has tripled. The implications of this on timely treatment, complication rates and mortality need further longer term exploration.

Social Deprivation and Incident Diabetes-Related Foot Disease in Patients With Type 2 Diabetes: A Population-Based Cohort Study

OBJECTIVE

To investigate the relationship between social deprivation and incident diabetes-related foot disease (DFD) in newly diagnosed patients with type 2 diabetes.

RESEARCH DESIGN AND METHODS

A population-based open retrospective cohort study using The Health Improvement Network (1 January 2005 to 31 December 2019) was conducted. Patients with type 2 diabetes free of DFD at baseline were stratified by Townsend deprivation index, and risk of developing DFD was calculated. DFD was defined as a composite of foot ulcer (FU), Charcot arthropathy, lower-limb amputation (LLA), peripheral neuropathy (PN), peripheral vascular disease (PVD), and gangrene.

RESULTS

A total of 176,359 patients were eligible (56% men; mean age 62.9 [SD 13.1] years). After excluding 26,094 patients with DFD before/within 15 months of type 2 diabetes diagnosis, DFD incidentally developed in 12.1% of the study population over 3.27 years (interquartile range 1.41-5.96). Patients in the most deprived Townsend quintile had increased risk of DFD compared with those in the least deprived (adjusted hazard ratio [aHR] 1.22; 95% CI 1.16-1.29) after adjusting for sex, age at type 2 diabetes diagnosis, ethnicity, smoking, BMI, HbA_1c, cardiovascular disease, hypertension, retinopathy, estimated glomerular filtration rate, insulin, glucose/lipid-lowering medication, and baseline foot risk. Patients in the most deprived Townsend quintile had higher risk of PN (aHR 1.18; 95% CI 1.11-1.25), FU (aHR 1.44; 95% CI 1.17-1.77), PVD (aHR 1.40; 95% CI 1.28-1.53), LLA (aHR 1.75; 95% CI 1.08-2.83), and gangrene (aHR 8.49; 95% CI 1.01-71.58) compared with those in the least.

CONCLUSIONS

Social deprivation is an independent risk factor for the development of DFD, PN, FU, PVD, LLA, and gangrene in newly diagnosed patients with type 2 diabetes. Considering the high individual and economic burdens of DFD, strategies targeting patients in socially deprived areas are needed to reduce health inequalities.

Incident Type 2 Diabetes and Risk of Fracture: A Comparative Cohort Analysis Using U.K. Primary Care Records

OBJECTIVE

To estimate risk of fracture in men and women with recent diagnosis of type 2 diabetes compared with individuals without diabetes.

RESEARCH DESIGN AND METHODS

In this cohort study, we used routinely collected U.K. primary care data from The Health Improvement Network. In adults (>35 years) diagnosed with type 2 diabetes between 2004 and 2013, fractures sustained until 2019 were identified and compared with fractures sustained in individuals without diabetes. Multivariable models estimated time to first fracture following diagnosis of diabetes. Annual prevalence rates included at least one fracture in a given year.

RESULTS

Among 174,244 individuals with incident type 2 diabetes and 747,290 without diabetes, there was no increased risk of fracture among males with diabetes (adjusted hazard ratio [aHR] 0.97 [95% CI 0.94, 1.00]) and a small reduced risk among females (aHR 0.94 [95% CI 0.92, 0.96]). In those aged ≥85 years, those in the diabetes cohort were at significantly lower risk of incident fracture (males: aHR 0.85 [95% CI 0.71, 1.00]; females: aHR 0.85 [95% CI 0.78, 0.94]). For those in the most deprived areas, aHRs were 0.90 (95% CI 0.83, 0.98) for males and 0.91 (95% CI 0.85, 0.97) for females. Annual fracture prevalence rates, by sex, were similar for those with and without type 2 diabetes.

CONCLUSIONS

We found no evidence to suggest a higher risk of fracture following diagnosis of type 2 diabetes. After a diagnosis of type 2 diabetes, individuals should be encouraged to make positive lifestyle changes, including undertaking weight-bearing physical activities that improve bone health.

Validation of venous thromboembolism diagnoses in patients receiving rivaroxaban or warfarin in The Health Improvement Network

Purpose

To describe the effect that validation of venous thromboembolism (VTE) coded entries in the health improvement network (THIN) has on incidence rates of VTE among a cohort of rivaroxaban/warfarin users.

Methods

Among 36 701 individuals with a first prescription for rivaroxaban/warfarin between 2012 and 2015, we performed a two‐step VTE case identification process followed by a two‐step case validation process involving manual review of patient records. A valid case required a coded entry for VTE at some point after their first rivaroxaban/warfarin prescription with evidence of referral/hospitalization either as a coded entry or entered as free text. Positive predictive values (PPVs) with 95% confidence intervals (CIs) were calculated using validated cases as the gold standard. Incidence rates were calculated per 1000 person‐years with 95% CIs.

Results

We identified 2166 patients with a coded entry of VTE after their initial rivaroxaban/warfarin prescription; incidence rate of 45.31 per 1000 person‐years (95% CI: 43.49‐47.22). After manual review of patient records including the free text, there were 712 incident VTE cases; incidence rate of 14.90 per 1000 person‐years (95% CI: 13.85‐16.02). The PPV for coded entries of VTE alone was 32.9%, and the PPV for coded entries of VTE with a coded entry of referral/hospitalization was 39.8%; this increased to 69.6% after manual review of coded clinical entries in patient records.

Conclusions

Among rivaroxaban/warfarin users in THIN, valid VTE case identification requires manual review of patient records including the free text to prevent outcome misclassification and substantial overestimation of VTE incidence rates.

Toward the Development of Data Governance Standards for Using Clinical Free-Text Data in Health Research: Position Paper

BACKGROUND

Clinical free-text data (eg, outpatient letters or nursing notes) represent a vast, untapped source of rich information that, if more accessible for research, would clarify and supplement information coded in structured data fields. Data usually need to be deidentified or anonymized before they can be reused for research, but there is a lack of established guidelines to govern effective deidentification and use of free-text information and avoid damaging data utility as a by-product.

OBJECTIVE

This study aimed to develop recommendations for the creation of data governance standards to integrate with existing frameworks for personal data use, to enable free-text data to be used safely for research for patient and public benefit.

METHODS

We outlined data protection legislation and regulations relating to the United Kingdom for context and conducted a rapid literature review and UK-based case studies to explore data governance models used in working with free-text data. We also engaged with stakeholders, including text-mining researchers and the general public, to explore perceived barriers and solutions in working with clinical free-text.

RESULTS

We proposed a set of recommendations, including the need for authoritative guidance on data governance for the reuse of free-text data, to ensure public transparency in data flows and uses, to treat deidentified free-text data as potentially identifiable with use limited to accredited data safe havens, and to commit to a culture of continuous improvement to understand the relationships between the efficacy of deidentification and reidentification risks, so this can be communicated to all stakeholders.

CONCLUSIONS

By drawing together the findings of a combination of activities, we present a position paper to contribute to the development of data governance standards for the reuse of clinical free-text data for secondary purposes. While working in accordance with existing data governance frameworks, there is a need for further work to take forward the recommendations we have proposed, with commitment and investment, to assure and expand the safe reuse of clinical free-text data for public benefit.

Exploring novel diabetes surveillance methods: a comparison of administrative, laboratory and pharmacy data case definitions using THIN

Background

The objective of this study was to identify patients with diabetes in a comprehensive primary care electronic medical records database using a number of different case definitions (clinical, pharmacy, laboratory definitions and a combination thereof) and understand the differences in patient populations being captured by each definition.

Methods

Data for this population-based retrospective cohort study was obtained from The Health Information Network (THIN). THIN is a longitudinal, primary care medical records database of over 9 million patients in UK. Primary outcome was a diagnosis of diabetes, defined by the presence of a diabetes read code, or an abnormal laboratory result, or a prescription for an Oral Anti-diabetic drug or insulin. A 2-year washout period was applied prior to the index of diabetes to avoid inclusion of prevalent cases for each case definition.

Results

This study demonstrated that different case definitions of diabetes identify different sub-populations of patients. When the cohorts were observed based on any measure of central tendency, each of the cohorts were reasonably comparable to each other. However, the distribution of each of the cohorts when grouped by age categories and sex, reveal differences. For example, using pharmacy case definition results in a bimodal distribution among women, one between 1-19 year and 35-39 age categories, and then again between 60-64 and 85 years-however, the histogram becomes more normally distributed when metformin was removed from the case definition.

Conclusion

Our results suggest that clinical, pharmacy, laboratory case definitions identify different sub-populations and using multiple case definitions is likely required to optimally identify the entire diabetes population within THIN. Our study also suggests that age and sex of patients may affect the indexing of diabetes in THIN and is critical to better understand these variations.

Treatment patterns in UK adult patients with atopic dermatitis treated with systemic immunosuppressants: data from The Health Improvement Network (THIN)

Background: There is limited understanding on patterns of systemic treatment in adults with moderate-to-severe atopic dermatitis (AD) in the UK.Objective: To characterize treatment patterns in adult AD patients prescribed immunosuppressants (IMMs) in the primary care setting.Results: Six hundred and fifty-six patients with AD (6.6%) were prescribed IMM in the analysis (mean age 52.1 years; 59.1% female; age-adjusted Charlson comorbidity index 1.4). Most prevalent (>5%) conditions at baseline were depression (10.8%), contact dermatitis (10.7%), rheumatological disease (7.9%), skin/subcutaneous tissue disorders (6.4%), upper respiratory disease (5.8%), and psoriasis (5.2%). At baseline, up to 50% of patients were prescribed ≥1 IMM. During follow-up, 42.7% of patients were prescribed oral corticosteroids (OCSs), increasing in line with IMM exposure. The most commonly prescribed IMM was methotrexate (43.3%). Ciclosporin, the only approved IMM for AD, was prescribed to 16.9% of patients.Conclusions: The prevalence of comorbidities and high rate of IMM prescriptions demonstrate the impact of AD on quality of life. The frequency of OCS prescribing in AD patients treated with IMMs suggests a lack of disease control with existing therapies, and an unmet need for safe and effective targeted agents for long-term disease control.

Feasibility and validity of The Health Improvement Network database of primary care electronic health records to identify and characterise patients with small cell lung cancer in the United Kingdom

Background

Epidemiological research on small cell lung cancer (SCLC) is limited and based on cancer registry data. We evaluated the feasibility and validity of using primary care electronic health records (The Health Improvement Network [THIN]) in the UK to identify and characterise SCLC.

Methods

We searched THIN records of individuals aged 18–89 years between 2000 and 2014 for a first diagnostic code suggestive of lung cancer (group 1) or small cell cancer (SCC; group 2) and for text strings among free text comments to identify and characterise incident SCLC cases. We validated our case identification strategy by manual review of patient EHRs, including free text comments, for a random sample of 400 individuals initially detected with a diagnostic code (300 from group 1 and 100 from group 2).

Results

Twenty five thousand two hundred fourty one individuals had a code for lung cancer (n = 24,508 [97.1%]) or SCC (733 [2.9%]). Following free-text searches, there were 3530 incident SCLC cases (2956 from group 1; 574 from group 2) corresponding to an incidence rate of 1.01 per 10,000 person-years. In the validation exercise, SCLC confirmation rates were 99% (group 1) and 85% (group 2). Mean age at diagnosis among confirmed cases was 68.5 years; staging information was present in 63.5% of cases of whom 17.8% had limited disease and 82.2% had extensive disease. The majority (84.5%) had a recorded symptom suggestive of lung cancer; chest infection was the most common (18%) followed by cough (15.8%) and chest/abdominal/back pain (15.2%). The first year crude mortality rates was 9.9 per 100 person-months (95% confidence interval [CI] 9.5–10.4), was higher among men and those aged 80 years and above. A total of 144 (37.8%) confirmed cases had metastases recorded. Median survival among the whole study cohort was 7.37 months.

Conclusions

Our SCLC case identification method appears to be valid and could potentially be adapted to identify other cancer types. However, complete characterisation of staging requires information from additional data sources including cancer registries.

Electronic supplementary material

The online version of this article (10.1186/s12885-019-5305-1) contains supplementary material, which is available to authorized users.

Linkage of national soil quality measurements to primary care medical records in England and Wales: a new resource for investigating environmental impacts on human health

Background

Long-term, low-level exposure to toxic elements in soil may be harmful to human health but large longitudinal cohort studies with sufficient follow-up time to study these effects are cost-prohibitive and impractical. Linkage of routinely collected medical outcome data to systematic surveys of soil quality may offer a viable alternative.

Methods

We used the Geochemical Baseline Survey of the Environment (G-BASE), a systematic X-ray fluorescence survey of soil inorganic chemistry throughout England and Wales to obtain estimates of the concentrations of 15 elements in the soil contained within each English and Welsh postcode area. We linked these data to the residential postcodes of individuals enrolled in The Health Improvement Network (THIN), a large database of UK primary care medical records, to provide estimates of exposure. Observed exposure levels among the THIN population were compared with expectations based on UK population estimates to assess representativeness.

Results

Three hundred seventy-seven of three hundred ninety-five English and Welsh THIN practices agreed to participate in the linkage, providing complete residential soil metal estimates for 6,243,363 individuals (92% of all current and former patients) with a mean period of prospective computerised medical data collection (follow-up) of 6.75 years. Overall agreement between the THIN population and expectations was excellent; however, the number of participating practices in the Yorkshire & Humber strategic health authority was low, leading to restricted ranges of measurements for some elements relative to the known variations in geochemical concentrations in this area.

Conclusions

The linked database provides unprecedented population size and statistical power to study the effects of elements in soil on human health. With appropriate adjustment, results should be generalizable to and representative of the wider English and Welsh population.

Electronic supplementary material

The online version of this article (10.1186/s12963-018-0168-2) contains supplementary material, which is available to authorized users.

Risk factors for diabetic macular oedema in type 2 diabetes: A case-control study in a United Kingdom primary care setting

AIM

To identify risk factors associated with the development of DMO among patients diagnosed with type 2 diabetes managed in a primary care setting in the UK.

METHODS

A case-control study nested in a cohort of incident Type 2 diabetes identified in The Health Improvement Network database from 2000-2007. Cases were people with DMO (N=211) and controls were a DMO-free sample (N=2194). No age restrictions were applied. Adjusted odds ratios and 95%CIs were estimated (OR; 95%CI).

RESULTS

DMO increased with high alcohol use (2.88; 1.49-5.55), cataracts (4.10; 2.73-6.15), HbA1c ≥7% (1.58; 1.08-2.32), systolic blood pressure ≥160mm Hg (2.03; 1.17-3.53), total cholesterol ≥5mmol/L (1.66; 1.15-2.39), LDL ≥3mmol/L (1.73; 1.14-2.61), and microalbuminuria (1.78; 1.16-2.73). Diuretic drugs were associated with a reduced risk of DMO (0.68; 0.47-0.99), as did smoking (0.47; 0.28-0.77), overweight (0.53; 0.30-0.96) or obesity (0.52; 0.30-0.91) at diabetes diagnosis, and high triglyceride levels (0.51; 0.35-0.74). Patients treated with anti-diabetic drugs showed higher risk of DMO than non-treated patients, particularly those with sulphonylureas (3.40; 2.42-4.78), insulin (3.21; 1.92-5.36) or glitazones (1.88; 1.17-3.04).

CONCLUSION

In patients with type 2 diabetes managed in primary care, multiple factors associated with DMO were identified, such as cataracts, microalbuminuria and high levels of HbA1c, systolic BP, total cholesterol, and LDL. Diuretic drugs were associated with a reduced risk of DMO. Treated diabetes, particularly with sulphonylureas, insulin or glitazones showed highest risk of DMO. The inverse association between smoking, obesity, and triglycerides and DMO deserves further research.

Effectiveness of Liraglutide and Lixisenatide in the Treatment of Type 2 Diabetes: Real-World Evidence from The Health Improvement Network (THIN) Database in the United Kingdom

INTRODUCTION

The glucagon-like peptide-1 receptor agonists liraglutide and lixisenatide are effective at reducing glycated hemoglobin (HbA1c) levels in patients with type 2 diabetes mellitus (T2DM). Although liraglutide has demonstrated superior efficacy in head-to-head clinical trials, real-world evidence of comparative effectiveness is lacking. This observational study aimed to assess the effectiveness of liraglutide versus lixisenatide in UK clinical practice.

METHODS

Electronic medical records from The Health Improvement Network (THIN) UK primary care database were analyzed. Patients aged ≥18 years, diagnosed with T2DM, and prescribed liraglutide or lixisenatide between 01 May 2013 and 31 December 2015 were included in the study. Adjusted linear regression models compared the difference in mean change in HbA1c, body mass index (BMI), and systolic blood pressure (SBP) after 12-month follow-up. The proportion of patients achieving glycemic control (HbA1c <6.5%, <7.0%, <7.5%); HbA1c reduction >1%; and weight reduction ≥3% within 12 months were determined. Cox proportional hazards modeling was used to evaluate the effect of treatment on time to achieving HbA1c and weight reduction targets. Healthcare resource use (HCRU) (GP, secondary care, hospitalizations) was compared using analysis of covariance.

RESULTS

The primary outcome was assessed in 579 liraglutide and 213 lixisenatide new users. Fully adjusted linear regression indicated that liraglutide reduced HbA1c significantly more than lixisenatide (mean treatment difference -0.30; 95% CI -0.56, -0.04; p = 0.025). Compared to lixisenatide, liraglutide recipients were 2.5 times more likely to achieve HbA1c <6.5% (p = 0.0002). Liraglutide users were also more likely to achieve HbA1c <7.0% (HR 2.10; p < 0.0001), <7.5% (HR 1.65; p < 0.0001), and >1% HbA1c reduction (HR 1.29; p = 0.0002). BMI and SBP reductions were greater for the liraglutide group but results were not significant. HCRU was comparable between treatment groups.

CONCLUSION

These results from the THIN database indicate that liraglutide treatment provided better outcomes related to glycemic control.

FUNDING

Novo Nordisk.

Prescribing of cyproterone acetate/ethinylestradiol in UK general practice: a retrospective descriptive study using The Health Improvement Network

OBJECTIVE

To investigate prescribing patterns of cyproterone acetate/ethinylestradiol (CPA/EE) in the United Kingdom before and after the 2013 prescribing guidance.

STUDY DESIGN

We conducted a retrospective descriptive study in UK general practice. The study population included women with a first prescription (index date) for CPA/EE in The Health Improvement Network in 2011 (N=2760), 2012 (N=2923) and 2014 (N=2341). We evaluated the proportion of new CPA/EE users with (i) a diagnosis of a hyperandrogenic condition, menstrual problem, consultation for contraception management, and other acne treatment, in the year before the index date; and (ii) proportion of new CPA/EE users with concomitant use of another hormonal contraceptive (HC).

RESULTS

The percentage of CPA/EE new users with a record of a hyperandrogenic condition was 61% in 2011, 62% in 2012 and 63% in 2014. Corresponding percentages for acne were 51%, 54% and 55%, respectively. When manually reviewing patient records for a sample of CPA/EE new users (n=200), the acne was recorded in 77% of women, hirsutism in 9.5% and polycystic ovary syndrome in 9.5%. Majority of CPA/EE users had a prior acne diagnosis and/or treatment, 76% (n=2091) in 2011, 79% (n=2296) in 2012 and 78% (n=1834) in 2014. Concomitant use of CPA/EE and another HC was rare, 1% of CPA/EE users in 2011 and fewer than 0.5% of CPA/EE users in both 2012 and 2014.

CONCLUSIONS

Before and after 2013, the majority of UK women starting treatment with CPA/EE had a condition in line with its approved indication and had received prior acne treatment as per guidance.

Risk factors for diabetic retinopathy in people with Type 2 diabetes: A case-control study in a UK primary care setting

AIM

To identify risk factors of diabetic retinopathy (DR) among people with Type 2 diabetes mellitus in UK primary care.

METHODS

A case-control study nested in a cohort of incident Type 2 diabetes identified in The Health Improvement Network database from 2000 to 2007. Cases were people with DR (N=7735) and controls were a DR-free sample (N=9395). No age restrictions were applied. Adjusted odds ratios and 95% CIs were estimated.

RESULTS

21% of DR cases were identified during the first semester after Type 2 diabetes diagnosis. After controlling for delay on the Type 2 diabetes diagnosis, the DR risk increased with the duration of diabetes. DR increased with a mean systolic BP ≥150mmHg (1.18; 1.10-1.27), high alcohol consumption (1.34; 1.11-1.61), glycated haemoglobin (≥75 to <86: 1.14; 1.00-1.31; ≥86 to <97mmol/mol: 1.25; 1.07-1.45; ≥97mmol/mol: 1.21; 1.07-1.37), microalbuminuria (1.16; 1.06-1.27), and retinal vein occlusion (2.47; 1.67-3.66). Glaucoma and retinal arterial occlusion showed an OR of 0.71 (0.60-0.84) and 0.63 (0.40-1.01), respectively. HDL ≥1.55mmol/l (0.88; 0.80-0.98), high triglycerides (2.3-5.6mmol/l: 0.90; 0.82-0.99; >5.6mmol/l: 0.85; 0.64-1.13) or smoking (0.89; 0.81-0.97) had a slightly reduced DR risk. Users of hypoglycaemic agents had an increased DR risk.

CONCLUSION

Some DR cases were identified near the diabetes diagnosis date suggesting that a delayed diabetes diagnosis is still common. Glaucoma, retinal arterial occlusion and high HDL levels were inversely associated with DR, while retinal vein occlusion, alcohol and other well-known risk factors were positively associated.

Validity and completeness of colorectal cancer diagnoses in a primary care database in the United Kingdom

Purpose

To validate the recorded diagnoses of colorectal cancer (CRC) and identify false negatives in The Health Improvement Network (THIN) primary care database.

Methods

We conducted a validation study of incident CRC cases in THIN among patients aged 40–89 years from 2000–2011. CRC Read code entries (N = 3805) were verified by manual review of patients' electronic medical records (EMRs) including free‐text comments. Incident CRC cases in THIN ascertained following manual review were validated against two data sources deemed gold standards: (i) questionnaires sent to primary care practitioners (PCPs; for a random sample of 100 potential CRC cases), and (ii) Hospital Episode Statistics (HES) among linked practices. False negatives in THIN were identified by searching for International Classification of Diseases‐10 codes related to CRC in HES.

Results

Of 3805 CRC cases identified in THIN via Read codes, 3033 patients (80.0%) were considered definite cases after manual review of EMRs. The positive predictive value (PPV) of CRC Read codes was 86.0% after removing patients identified from THIN via a Read code for ‘fast track referral for suspected CRC’. The response rate from PCPs was 87.0% (n = 87), and the PPV of CRC in THIN was 100% based on PCP questionnaires. Using HES, the PPV for CRC in THIN was 97.9% (556/568), and false negative rate was 6.1% (36/592).

Conclusions

CRC diagnostic Read codes in THIN have a high PPV, which is increased further following manual review of free‐text comments. The false negative rate of CRC diagnoses in THIN is low. © 2015 The Authors. Pharmacoepidemiology and Drug Safety published by John Wiley & Sons Ltd.

Type 1 diabetes is associated with an increased risk of fracture across the life span: a population-based cohort study using The Health Improvement Network (THIN)

OBJECTIVE

This study was conducted to determine if type 1 diabetes is associated with an increased risk of fracture across the life span.

RESEARCH DESIGN AND METHODS

This population-based cohort study used data from The Health Improvement Network (THIN) in the U.K. (data from 1994 to 2012), in which 30,394 participants aged 0-89 years with type 1 diabetes were compared with 303,872 randomly selected age-, sex-, and practice-matched participants without diabetes. Cox regression analysis was used to determine hazard ratios (HRs) for incident fracture in participants with type 1 diabetes.

RESULTS

A total of 334,266 participants, median age 34 years, were monitored for 1.9 million person-years. HR were lowest in males and females age <20 years, with HR 1.14 (95% CI 1.01-1.29) and 1.35 (95% CI 1.12-1.63), respectively. Risk was highest in men 60-69 years (HR 2.18 [95% CI 1.79-2.65]), and in women 40-49 years (HR 2.03 [95% CI 1.73-2.39]). Lower extremity fractures comprised a higher proportion of incident fractures in participants with versus those without type 1 diabetes (31.1% vs. 25.1% in males, 39.3% vs. 32% in females; P < 0.001). Secondary analyses for incident hip fractures identified the highest HR of 5.64 (95% CI 3.55-8.97) in men 60-69 years and the highest HR of 5.63 (95% CI 2.25-14.11) in women 30-39 years.

CONCLUSIONS

Type 1 diabetes was associated with increased risk of incident fracture that began in childhood and extended across the life span. Participants with type 1 diabetes sustained a disproportionately greater number of lower extremity fractures. These findings have important public health implications, given the increasing prevalence of type 1 diabetes and the morbidity and mortality associated with hip fractures.

Cardiovascular events and all-cause mortality in a cohort of 57,946 patients with type 2 diabetes: associations with renal function and cardiovascular risk factors

Background

Diabetes and chronic kidney disease (CKD) are independent predictors of death and cardiovascular events and their concomitant prevalence has increased in recent years. The aim of this study was to characterize the effect of the estimated glomerular filtration rate (eGFR) and other factors on the risk of death and cardiovascular events in patients with type 2 diabetes.

Methods

A cohort of 57,946 patients with type 2 diabetes who were aged 20–89 years in 2000–2005 was identified from The Health Improvement Network, a UK primary care database. Incidence rates of death, myocardial infarction (MI), and ischemic stroke or transient ischemic attack (IS/TIA) were calculated overall and by eGFR category at baseline. eGFR was calculated using the Modification of Diet in Renal Disease (MDRD) study equation. Death, MI and IS/TIA cases were detected using an automatic computer search and IS/TIA cases were further ascertained by manual review of medical records. Hazard ratios (HRs) and their corresponding 95% confidence intervals (CIs) for death, MI, and IS/TIA associated with eGFR category and other factors were estimated using Cox regression models adjusted for potential confounders.

Results

Overall incidence rates of death (mean follow-up time of 6.76 years), MI (6.64 years) and IS/TIA (6.56 years) were 43.65, 9.26 and 10.39 cases per 1000 person-years, respectively. A low eGFR (15–29 mL/min) was associated with an increased risk of death (HR: 2.79; 95% CI: 2.57–3.03), MI (HR: 2.33; 95% CI: 1.89–2.87) and IS/TIA (HR: 1.77; 95% CI: 1.43–2.18) relative to eGFR ≥ 60 mL/min. Other predictors of death, MI and IS/TIA included age, longer duration of diabetes, poor control of diabetes, hyperlipidemia, smoking and a history of cardiovascular events.

Conclusions

In patients with type 2 diabetes, management of cardiovascular risk factors and careful monitoring of eGFR may represent opportunities to reduce the risks of death, MI and IS/TIA.

Electronic supplementary material

The online version of this article (doi:10.1186/s12933-015-0204-5) contains supplementary material, which is available to authorized users.

Responsiveness of primary care services: development of a patient-report measure – qualitative study and initial quantitative pilot testing

Background

Primary care service providers do not always respond to the needs of diverse groups of patients, and so certain patients groups are disadvantaged. General practitioner (GP) practices are increasingly encouraged to be more responsive to patients’ needs in order to address inequalities.

Objectives

(1) Explore the meaning of responsiveness in primary care. (2) Develop a patient-report questionnaire for use as a measure of patient experience of responsiveness by a range of primary care organisations (PCOs). (3) Investigate methods of population mapping available to GP practices.

Design setting

PCOs, including GP practices, walk-in centres and community pharmacies.

Participants

Patients and staff from 12 PCOs in the East Midlands in the development stage, and 15 PCOs across three different regions of England in stage 3.

Interventions

To investigate what responsiveness means, we conducted a literature review and interviews with patients and staff in 12 PCOs. We developed, tested and piloted the use of a questionnaire. We explored approaches for GP practices to understand the diversity of their populations.

Main outcome measures

(1) Definition of primary care responsiveness. (2) Three patient-report questionnaires to provide an assessment of patient experience of GP, pharmacy and walk-in centre responsiveness. (3) Insight into challenges in collecting diversity data in primary care.

Results

The literature covers three overlapping themes of service quality, inequalities and patient involvement. We suggest that responsiveness is achieved through alignment between service delivery and patient needs, involving strategies to improve responsive service delivery, and efforts to manage patient expectations. We identified three components of responsive service delivery: proactive population orientation, reactive population orientation and individual patient orientation. PCOs tend to utilise reactive strategies rather than proactive approaches. Questionnaire development involved efforts to include patients who are ‘seldom heard’. The questionnaire was checked for validity and consistency and is available in three versions (GP, pharmacy, and walk-in centre), and in Easy Read format. We found the questionnaires to be acceptable to patients, and to have content validity. We produced some preliminary evidence of reliability and construct validity. Measuring and improving responsiveness requires PCOs to understand the characteristics of their patient population, but we identified significant barriers and challenges to this.

Conclusions

Responsiveness is a complex concept. It involves alignment between service delivery and the needs of diverse patient groups. Reactive and proactive strategies at individual and population level are required, but PCOs mainly rely on reactive approaches. Being responsive means giving good care equally to all, and some groups may require extra support. What this extra support is will differ in different patient populations, and so knowledge of the practice population is essential. Practices need to be motivated to collect and use diversity data. Future work needed includes further evaluation of the patient-report questionnaires, including Easy Read versions, to provide further evidence of their quality and acceptability; research into how to facilitative the use of patient experience data in primary care; and implementation of strategies to improve responsiveness, and evaluation of effectiveness.

Funding

The National Institute for Health Research Service Delivery and Organisation programme.

Changes in HbA1c and frequency of measuring HbA1c and adjusting glucose-lowering medications in the 10 years following diagnosis of type 2 diabetes: a population-based study in the UK

AIMS/HYPOTHESIS

The aim of this work was to study levels of HbA1c and patterns of adjusting glucose-lowering drugs in patients with impaired glycaemic control over 10 years after diagnosis of type 2 diabetes.

METHODS

We studied 4,529 individuals in The Health Improvement Network Database newly diagnosed with type 2 diabetes in the year 2000.

RESULTS

From 6 months to 10 years after diagnosis, the HbA1c increased from 7.04% (53.4 mmol/mol) to 7.49% (58.3 mmol/mol) (average annual change: 0.047% [0.51 mmol/mol]). The greatest annual change occurred between 6 months and 2 years (0.21% [2.30 mmol/mol] increase per year, p < 0.001), followed by the 2-5 year time period (0.033% [0.36 mmol/mol] increase per year, p < 0.001). No significant increase in HbA1c occurred between 5 and 10 years (p = 0.20). In multivariable analyses, patients who were younger (p < 0.001), with higher BMI (p = 0.033) and who were current insulin users (p = 0.024) at diagnosis had greater increases in HbA1c between 6 months and 2 years. For individuals with HbA1c above 7.0% (53 mmol/mol) the mean time to next measurement of HbA1c was 0.53 years and increase in doses or changes to other glucose-lowering medications were performed in 26% of cases.

CONCLUSIONS/INTERPRETATION

HbA1c increases by approximately 0.5% (5 mmol/mol) over 10 years after diagnosis of type 2 diabetes, with the main increase appearing in the first years after diagnosis. More frequent monitoring of HbA1c and adjustments of glucose-lowering drugs may be essential to prevent the decline.

Incidence of retinal complications in a cohort of newly diagnosed diabetic patients

Purpose

We aimed at estimating the incidence of diabetic retinopathy (DR) and maculopathy (DMP) among newly diagnosed type 1 (t1DM) and type 2 diabetic patients (t2DM) in the United Kingdom primary care system. The incidence of DMP among patients with DR was also estimated.

Method

We conducted a cohort study using The Health Improvement Network database. The cohort included 64,983 incident diabetic patients (97.3% were t2DM) aged 1–84 years diagnosed between 2000 and 2007. This cohort was followed from the date of diabetes diagnosis until recording of DR or DMP in two separate follow-ups. Follow-up was censored at 85 years of age, death, or end of 2008. An additional follow-up was conducted from DR to DMP diagnosis using similar censoring reasons. DR and DMP cumulative incidences were calculated as well as incidence rates (IR; cases per 1,000 person-years) per calendar period (2000–2001 and 2006–2007).

Results

Follow-up for DR: 9 years after diabetes diagnosis, 28% of t2DM and 24% of t1DM patients had developed DR (7,899 incident DR cases). During the first 2 years with diabetes, the IR was almost 2 times higher in patients diagnosed with diabetes in 2006–2007 (47.7) than among those diagnosed in 2000–2001 (24.5). Follow-up for DMP: 9 years after diabetes diagnosis, 3.6% of t2DM and 4.4% of t2DM patients had developed DMP (912 incident DMP cases). During the first 2 years with diabetes, the IR was three times higher in patients diagnosed with diabetes in 2006–2007 (5.8) than among those diagnosed in 2000–2001 (1.8). Macular oedema occurred in 0.8% of patients.

Conclusions

In a cohort of incident diabetes, 28% of patients developed retinopathy and 4% maculopathy within the first 9 years. The 2-year IRs of DR and DMP were higher in patients diagnosed with diabetes during the period 2006–2007 than in those diagnosed during the 2000–2001 period.

Distinguishing incident and prevalent diabetes in an electronic medical records database

PURPOSE

To develop a method to identify incident diabetes mellitus (DM) using an electronic medical records (EMR) database and test this classification by comparing incident and prevalent DM with common outcomes related to DM duration.

METHODS

Incidence rates (IRs) of DM (defined as a first diagnosis or prescription) were measured in 3-month intervals through 36 months after registration in The Health Improvement Network, a primary care database, from 1994 to 2012. We used Joinpoint regression to identify the point where a statistically significant change in the trend of IRs occurred. Further analyses used this point to distinguish those likely to have incident (n = 50 315) versus prevalent (n = 28 337) DM. Incident and prevalent cohorts were compared using Cox regression for all-cause mortality, cardiovascular disease (CVD), diabetic retinopathy, diabetic nephropathy, and diabetic neuropathy. Analyses were adjusted for age, sex, smoking, obesity, hyperlipidemia, hypertension, and calendar year.

RESULTS

Trends in DM IRs plateaued 9 months after registration (p = 0.04). All cause-mortality was increased (hazard ratio (HR) 1.62, 95% CI 1.53-1.70) among patients diagnosed with DM prior to 9 months following registration (prevalent DM) compared to those diagnosed after 9 months (incident DM). Similarly, the risk of DM-related complications was higher in prevalent versus incident DM patients [CVD, HR 2.24 (2.08-2.40); diabetic retinopathy, HR 1.31 (1.24-1.38); diabetic nephropathy, HR 2.30 (1.95-2.72); diabetic neuropathy, HR 1.28 (1.16-1.41)].

CONCLUSION

Joinpoint regression can be used to identify patients with newly diagnosed diabetes within EMR data. Failure to exclude patients with prevalent DM can lead to exaggerated associations of DM-related outcomes.

Study of long-acting reversible contraceptive use in a UK primary care database: validation of methodology

OBJECTIVES To develop and validate algorithms to identify new users of long-acting reversible contraceptives (LARCs) in a primary care database, The Health Improvement Network (THIN). METHODS Women in THIN aged 12 to 49 years in 2005 were studied. THIN was searched using Read and MULTILEX codes to identify new users of copper intrauterine devices (Cu-IUDs), the levonorgestrel-releasing intrauterine system (LNG-IUS) and progestogen-only implants. Validation was undertaken for a randomly selected sample of 398 LARC users, in which their primary care physicians were asked to complete a questionnaire detailing LARC use. RESULTS Questionnaires were received for 379 patients (95%), confirming 316 (83%) as new LARC users. Confirmation rates for Cu-IUDs, the LNG-IUS and progestogen-only implants were 64%, 94% and 89%, respectively. The use of Read codes alone had the lowest confirmation rate, particularly for Cu-IUD users. Confirmation rates increased by using MULTILEX codes when available, or by examination of computerised medical records. CONCLUSIONS Computer algorithms were used to identify new LARC users. While THIN is a useful resource for studying LARC uptake, steps to gather additional information are necessary to ensure the validity of LARC classification.