Standardizing to specific target populations in distributed networks and multisite pharmacoepidemiologic studies.

Distributed network studies and multisite studies assess drug safety and effectiveness in diverse populations by pooling information. Targeting groups of clinical or policy interest (including specific sites or site combinations) and applying weights based on effect measure modifiers (EMMs) prior to pooling estimates within multisite studies may increase interpretability and improve precision. We simulated a 4-site study, standardized each site using inverse odds weights (IOWs) to resemble the 3 smallest sites or the smallest site, estimated IOW-weighted risk differences (RDs), and combined estimates with inverse variance weights (IVWs). We also created an artificial distributed network in the Clinical Practice Research Datalink (CPRD) Aurum consisting of 1 site for each geographic region. We compared metformin and sulfonylurea initiators with respect to mortality, targeting the smallest region. In the simulation, IOWs reduced differences between estimates and increased precision when targeting the 3 smallest sites or the smallest site. In the CPRD Aurum study, the IOW + IVW estimate was also more precise (smallest region: RD = 5.41% [95% CI, 1.03-9.79]; IOW + IVW estimate: RD = 3.25% [95% CI, 3.07-3.43]). When performing pharmacoepidemiologic research in distributed networks or multisite studies in the presence of EMMs, designation of target populations has the potential to improve estimate precision and interpretability. This article is part of a Special Collection on Pharmacoepidemiology.

Efficacy of interventions targeted at physician prescribers of opioids for chronic non-cancer pain: an overview of systematic reviews.

BACKGROUND: To combat the opioid crisis, interventions targeting the opioid prescribing behaviour of physicians involved in the management of patients with chronic non-cancer pain (CNCP) have been introduced in clinical settings. An integrative synthesis of systematic review evidence is required to better understand the effects of these interventions. Our objective was to synthesize the systematic review evidence on the effect of interventions targeting the behaviours of physician opioid prescribers for CNCP among adults on patient and population health and prescriber behaviour. METHODS: We searched MEDLINE, Embase, and PsycInfo via Ovid; the Cochrane Database of Systematic Reviews; and Epistemonikos. We included systematic reviews that evaluate any type of intervention aimed at impacting opioid prescriber behaviour for adult CNCP in an outpatient setting. RESULTS: We identified three full texts for our review that contained 68 unique primary studies. The main interventions we evaluated were structured prescriber education (one review) and prescription drug monitoring programmes (PDMPs) (two reviews). Due to the paucity of data available, we could not determine with certainty that education interventions improved outcomes in deprescribing. There is some evidence that PDMPs decrease the number of adverse opioid-related events, increase communication among healthcare workers and patients, modify healthcare practitioners' approach towards their opioid prescribed patients, and offer more chances for education and counselling. CONCLUSIONS: Our overview explores the possibility of PDMPs as an opioid deprescribing intervention and highlights the need for more high-quality primary research on this topic.

Incretin-based drugs and the risk of diabetic retinopathy among individuals with type 2 diabetes: A systematic review and meta-analysis of observational studies.

AIM: The results from the SUSTAIN-6 trial generated some uncertainty regarding the association between incretin-based drugs [dipeptidyl peptidase-4 (DPP-4) inhibitors and glucagon-like peptide-1 receptor agonists (GLP-1 RAs)] and the risk of diabetic retinopathy. Our objective was to synthesize the available evidence from observational studies regarding the use of incretin-based drugs and the risk of diabetic retinopathy among individuals with type 2 diabetes. MATERIALS AND METHODS: We systemically searched Cochrane Library, Embase and Medline to identify observational studies of interest. Risk of bias was assessed using the ROBINS-I tool. Data from included studies were pooled using the DerSimonian and Laird random-effect model with the Hartung-Knapp extension. RESULTS: We included 14 studies in the systematic review, with 10 examining DPP-4 inhibitors and seven examining GLP-1 RAs. Nine studies investigated incident diabetic retinopathy, six investigated diabetic retinopathy progression and two investigated both outcomes. Seven studies were at moderate risk of bias, four at serious risk of bias and three at critical risk of bias. Data pooled across studies showed no association between the use of DPP-4 inhibitors (risk ratio: 0.98, 95% confidence interval: 0.83, 1.17) or GLP-1 RAs (risk ratio: 0.87, 95% confidence interval: 0.56, 1.34) and the risk of diabetic retinopathy. CONCLUSION: This study suggests that the use of incretin-based drugs is not associated with the risk of diabetic retinopathy among individuals with type 2 diabetes. However, these findings should be interpreted with caution considering the limited quality of some of the available evidence.

Fluoroquinolones and the risk of severe hypoglycaemia among sulphonylurea users: Population-based cohort study.

AIM: Fluoroquinolone-related hypoglycaemia is rare but may become clinically relevant in individuals at high baseline hypoglycaemic risk, such as patients with diabetes using sulphonylureas. Our population-based cohort study assessed whether fluoroquinolones are associated with an increased risk of severe hypoglycaemia compared with amoxicillin among patients treated with sulphonylureas. MATERIALS AND METHODS: Using the UK's Clinical Practice Research Datalink Aurum linked to hospitalization and vital statistics data, we assembled a base cohort of patients who initiated second-generation sulphonylureas (1998-2020). The study cohort included patients initiating either fluoroquinolones or amoxicillin while on sulphonylureas. Using an intent-to-treat exposure definition, we assessed the 30-day risk of severe hypoglycaemia (hospitalization with or death because of hypoglycaemia) associated with fluoroquinolones compared with amoxicillin. Cox models estimated hazard ratios (HRs) with 95% confidence intervals (CIs) of severe hypoglycaemia after 1:5 matching on previous sulphonylurea use and propensity scores. Secondary analyses were stratified by demographics and glycated haemoglobin. RESULTS: Overall, 143 417 patients initiated fluoroquinolones (n = 13 123) or amoxicillin (n = 130 294) while on sulphonylureas. Compared with amoxicillin, fluoroquinolones were not associated with the risk of severe hypoglycaemia (HR, 1.17; 95% CI, 0.91-1.50). Fluoroquinolones were associated with an increased risk in patients <65 years (HR, 2.90; 95% CI, 1.41-5.97) but not in those ≥65 years (HR, 1.03; 95% CI, 0.79-1.35) in stratified analyses. There was no evidence of effect modification by sex or glycated haemoglobin. CONCLUSIONS: In patients using second-generation sulphonylureas, fluoroquinolones were not associated with an increased risk of severe hypoglycaemia compared with amoxicillin. An increased risk among younger adults is possible.

A systematic review and meta-analysis comparing outcomes between using subcutaneous insulin and continuous insulin infusion in managing adult patients with diabetic ketoacidosis.

BACKGROUND: The purpose of this systematic review and meta-analysis was to synthesize the current literature to determine the safety and efficacy of using subcutaneous insulin compared to an intravenous (IV) insulin infusion in managing diabetic ketoacidosis (DKA). METHODS: We searched Ovid-Medline, EMBASE, SCOPUS, BIOSIS and CENTRAL from inception to April 26, 2024. Randomized controlled trials (RCTs) and observational studies that assessed the use of subcutaneous compared to intravenous insulin for the treatment of mild to moderate DKA were included. Data extraction and quality assessment were performed by two independent reviewers and disagreements were resolved through further discussion or by a third reviewer. The Cochrane Risk of Bias tool version 2.0 was used to evaluate the RCTs and the Risk of Bias in Non-randomized Studies of Interventions (ROBINS)-I tool was used to evaluate the observational studies. The quality of evidence was assessed using the Grading of Recommendations Assessment, Development, and Evaluation (GRADE) criteria. Meta-analyses were conducted using random-effects models. We followed the PRISMA guidelines for reporting our findings. RESULTS: Six RCTs (245 participants) and four observational studies (8444 patients) met our inclusion criteria. Some studies showed a decreased length of stay (Mean Difference [MD] in days: -0.39; 95% CI: -2.83 to 2.08; I2: 0%) among individuals treated with subcutaneous insulin compared to intravenous insulin. There was no difference in the risk of all-cause mortality, time to resolution of DKA (MD in hours: 0.17; 95% confidence interval [CI]: -3.45 to 3.79; I2: 0%) and hypoglycemia (Risk Ratio [RR]: 1.02; 95% CI: 0.88 to 1.19; I2: 0%) between the two groups. CONCLUSION: Treatment of DKA with subcutaneous insulin may be a safe and effective alternative to IV insulin in selected patients. The limited available evidence underscores the need for further studies to explore optimal dosing, patient selection criteria and long-term outcomes.

Prescribing trends of proton pump inhibitors and histamine blockers among children in the United Kingdom (1998-2019): A population-based assessment.

PURPOSE: To describe the prescribing trends of proton pump inhibitors (PPIs) and H2 receptor antagonists (H2 RAs) among children with gastroesophageal reflux in the United Kingdom between 1998 and 2019. METHODS: We conducted a population-based retrospective cohort study using data from the Clinical Practice Research Datalink that included all children aged ≤18 years with a first ever diagnosis of gastroesophageal reflux between 1998 and 2019. Using negative binomial regression, we estimated crude and adjusted annual prescription rates per 1000 person-years and corresponding 95% confidence intervals (CIs) for PPIs and H2 RAs. We also assessed rate ratios of PPIs and H2 RAs prescription rates to examine changes in prescribing over time. RESULTS: Our cohort included 177 477 children with a first ever diagnosis of gastroesophageal reflux during the study period. The median age was 13 years (IQR: 1, 17) among children prescribed PPIs and 0.2 years (IQR: 0.1, 0.6) among those prescribed H2 RAs. The total prescription rate of all GERD drugs was 1468 prescriptions per 1000 person-years (PYs) (95% CI 1463-1472). Overall, PPIs had a higher prescription rate (815 per 1000 PYs, 95% CI 812-818) than H2 RAs (653 per 1000 PYs 95% CI 650-655). Sex- and age-adjusted rate ratios of 2019 versus 1998 demonstrated a 10% increase and a 76% decrease in the prescription rates of PPIs and H2 RAs, respectively. CONCLUSIONS: Prescription rates for PPIs increased, especially during the first half of the study period, while prescription rates for H2 RA decreased over time.

Maternal hypothyroidism and subsequent metabolic outcomes in children: a systematic review and meta-analysis.

INTRODUCTION: As the fetus relies on maternal thyroid hormones in early pregnancy, maternal hypothyroidism plays an important role in fetal development. However, the association between maternal hypothyroidism and metabolic disease in offspring is unclear. OBJECTIVE: To examine the association between maternal hypothyroidism in pregnancy and metabolic outcomes (obesity, hypertension, type 2 diabetes mellitus, and dyslipidemia) in children < 18 years. METHODS: We systematically searched 5 databases from inception to May 2023. Eligible studies included cohort, case-control, and randomized controlled trials involving children born to mothers with or without hypothyroidism in pregnancy. Data were pooled across studies using random-effects models for outcomes reported in at least three studies. Quality assessment was performed using the ROBINS-E tool for observational studies and the Cochrane Risk of Bias tool for trials. RESULTS: The search identified 3221 articles, of which 7 studies were included (1 trial, 6 observational). All studies were conducted outside of North America and ranged in size from 250 to > 1 million children. The follow-up time ranged from 6 to 20 years. Included studies support an increased risk of hypertension and glucose dysregulation in offspring exposed to maternal hypothyroidism (hypertension: OR 1.08, 95% CI 0.75, 1.57 and HR 1.81, 95% CI 1.21, 2.69; diabetes: RR 2.7, 95% CI 0.7, 10). In the pooled analysis, maternal hypothyroidism was not associated with obesity in offspring (OR 1.04, 95% CI 0.64, 1.70). CONCLUSION: This study found inconsistent evidence on the association between maternal hypothyroidism in pregnancy and metabolic outcomes in offspring, though associations with hypertension and glucose dysregulation are possible.

Use of a Statistical Adaptive Treatment Strategy Approach for Emulating Randomized Controlled Trials Using Observational Data: The Example of Blood-Pressure Control Strategies for the Prevention of Cardiovascular Events Among Individuals With Hypertension at High Cardiovascular Risk.

Statistical approaches to adaptive treatment strategies (ATS) can be used to mimic the sequential decision-making inherently found in clinical practice. To illustrate the use of a statistical ATS approach, we emulated a target trial of different blood pressure (BP) control plans for the prevention of cardiovascular events among individuals with hypertension at high cardiovascular risk, inspired by the Systolic Blood Pressure Intervention Trial (SPRINT). We included 103,708 patients with hypertension and a "QRISK3" estimated 10-year risk of cardiovascular disease of ≥20% who initiated an antihypertensive drug between 1998 and 2018. Dynamic marginal structural models estimated the comparative effects of treating patients with intensive (target BP: 130/80 mm Hg), standard (140/90 mm Hg), and conservative (150/90 mm Hg) BP control strategies. The adjusted hazard ratios (HRs) for the intensive versus standard strategy were 0.96 (95% confidence interval (CI): 0.92, 1.00) for major adverse cardiovascular events and 0.93 (95% CI: 0.88, 0.97) for death from cardiovascular causes. For the conservative versus standard strategy, they were 1.06 (95% CI: 1.02, 1.10) and 1.08 (95% CI: 1.03, 1.13), respectively. These results are largely compatible with SPRINT. ATS can be used to emulate randomized controlled trials of complex treatment strategies in an observational setting and represents an alternative approach for situations where randomized controlled trials are not feasible.

Breaking Research Silos and Stimulating "Innovation at the Edges" in Epidemiology.

Epidemiological training often requires specialization in a subdiscipline (e.g., pharmacoepidemiology, genetic epidemiology, social epidemiology, or infectious disease epidemiology). While specialization is necessary and beneficial, it comes at the cost of decreased awareness of scientific developments in other subdisciplines of epidemiology. In this commentary, we argue for the importance of promoting an exchange of ideas across seemingly disparate epidemiologic subdisciplines. Such an exchange can lead to invaluable opportunities to learn from and merge knowledge across subdisciplines. It can promote "innovation at the edges," a process of borrowing and transforming methods from one subdiscipline in order to develop something new and advance another subdiscipline. Further, we outline specific actionable steps at the researcher, institution, and professional society level that can promote such innovation.

Association of adverse respiratory events with sodium-glucose cotransporter 2 inhibitors versus dipeptidyl peptidase 4 inhibitors among patients with type 2 diabetes in South Korea: a nationwide cohort study.

BACKGROUND: Impaired respiratory function remains underrecognized in patients with type 2 diabetes (T2D), despite common pulmonary impairment. Meanwhile, there is little data available on the respiratory effects of sodium glucose cotransporter 2 inhibitors (SGLT2i). Hence, we examined the association between SGLT2i use and the risk of adverse respiratory events in a real-world setting. METHODS: We conducted a population-based, nationwide cohort study using an active-comparator new-user design and nationwide claims data of South Korea from January 2015 to December 2020. Among individuals aged 18 years or older, propensity score matching was done to match each new user of SGLT2is with dipeptidyl peptidase 4 inhibitors (DPP4is), with patients followed up according to an as-treated definition. The primary outcome was respiratory events, a composite endpoint of acute pulmonary edema, acute respiratory distress syndrome (ARDS), pneumonia, and respiratory failure. Secondary outcomes were the individual components of the primary outcome and in-hospital death. Cox models were used to estimate hazard ratios (HRs) and 95% CIs. RESULTS: Of 205,534 patient pairs in the propensity score matched cohort, the mean age of the entire cohort was 53.8 years and 59% were men, with a median follow-up of 0.66 years; all baseline covariates achieved balance between the two groups. Incidence rates for overall respiratory events were 4.54 and 7.54 per 1000 person-years among SGLT2i and DPP4i users, respectively, corresponding to a rate difference of 3 less events per 1000 person-years (95% CI - 3.44 to - 2.55). HRs (95% CIs) were 0.60 (0.55 to 0.64) for the composite respiratory endpoint, 0.35 (0.23 to 0.55) for acute pulmonary edema, 0.44 (0.18 to 1.05) for ARDS, 0.61 (0.56 to 0.66) for pneumonia, 0.49 (0.31 to 0.76) for respiratory failure, and 0.46 (0.41 to 0.51) for in-hospital death. Similar trends were found across individual SGLT2is, subgroup analyses of age, sex, history of comorbidities, and a range of sensitivity analyses. CONCLUSIONS: These findings suggest a lower risk of adverse respiratory events associated with patients with T2D initiating SGLT2is versus DPP4is. This real-world evidence helps inform patients, clinicians, and guideline writers regarding the respiratory effects of SGLT2i in routine practice.

Use of metformin and insulin among pregnant women with gestation diabetes in the United Kingdom: A population-based cohort study.

AIMS: The contemporary prescription patterns of antidiabetic drugs following guideline changes recommending metformin as first-line gestational diabetes (GDM) pharmacotherapy is underexplored. We aimed to examined use of metformin and insulin during pregnancy among women with GDM over 20 years in the United Kingdom. METHODS: We conducted a population-based cohort study using linked data from the Clinical Practice Research Datalink, its pregnancy register and Hospital Episode Statistics from 1998 to 2017. We included pregnancies of women without prior diabetes history who received GDM diagnosis or initiated an antidiabetic drug after 20 weeks gestation. Patient-level and practice-level characteristics were compared between metformin initiators and insulin initiators. We described trends of initiating metformin as first-line treatment and described time to initiation of rescue insulin overall, and by body mass index among metformin initiators. RESULTS: Our cohort included 5633 pregnancies from 5393 women with GDM, of whom 38.9% initiated pharmacotherapy (41% insulin, 59% metformin). Metformin prescriptions (as opposed to insulin) increased substantially, from <5% of pregnancies before 2007 to 42.5% in 2008. Over 85% of pregnancies that were prescribed pharmacotherapy were prescribed metformin as first-line treatment in 2015. Among metformin initiators, 16% initiated rescue insulin, typically occurring within 40 days of metformin initiation. Choice of GDM pharmacotherapy varied by characteristics, including smoking, obesity, race/ethnicity and general practice regions. CONCLUSIONS: Metformin was the most prescribed medication for GDM, with large increases over the past 2 decades. The increasing use of oral-antidiabetic drugs during pregnancy, consistent with other regions, highlights the need for future studies examining effectiveness and safety of antidiabetic drug use during pregnancy.

Sulphonylureas versus metformin and the risk of ventricular arrhythmias among people with type 2 diabetes: A population-based cohort study.

AIM: To determine whether the use of sulphonylurea monotherapy, compared with metformin monotherapy, is associated with an increased risk of ventricular arrhythmia (VA) among patients initiating pharmacotherapy for type 2 diabetes. RESEARCH DESIGN AND METHODS: We conducted a population-based cohort study using electronic health data extracted from the UK's Clinical Practice Research Datalink Aurum. Using the active comparator, new-user cohort design, we compared rates of VA among patients aged 18 years or older using sulphonylurea monotherapy with those using metformin monotherapy as their initial pharmacological treatment for type 2 diabetes from April 1998 to December 2019. We used a Cox proportional hazards model with inverse probability of treatment weighting by propensity score to estimate the adjusted hazard ratio (aHR) and a corresponding bootstrap 95% confidence interval (CI) for VA with sulphonylurea monotherapy versus metformin monotherapy. RESULTS: The cohort included 92 638 new users of sulphonylurea and 506 882 new users of metformin. A total of 279 VA events occurred among sulphonylurea users (rate per 10 000 person-years: 25.5, 95% CI: 22.7 to 28.7) and 1537 VA events occurred among metformin users (rate per 10 000 person-years: 18.5, 95% CI: 17.6 to 19.5). Compared with metformin, sulphonylureas were associated with an increased risk of VA (aHR: 1.42, 95% CI: 1.18 to 1.69). CONCLUSIONS: Sulphonylureas are associated with an increased risk of VA when used as first-line therapy for type 2 diabetes relative to metformin use. This increased risk should be considered when prescribing sulphonylureas as an initial treatment for type 2 diabetes.

Long-acting insulin analogues and the risk of diabetic retinopathy among patients with type 2 diabetes: A population-based cohort study.

AIM: To determine whether the use of long-acting insulin analogues is associated with an increased risk of incident diabetic retinopathy (DR) among patients with type 2 diabetes. METHODS: Using data from the Clinical Practice Research Datalink Aurum, this retrospective, population-based cohort study included patients with type 2 diabetes who initiated a long-acting insulin analogue (glargine, detemir, degludec) or Neutral Protamine Hagedorn (NPH) insulin. The primary outcome was incident DR. We used Cox proportional hazards models with inverse probability of treatment weighting to estimate hazard ratios (HRs) and 95% confidence intervals (CIs) for incident DR with insulin analogues versus NPH insulin. RESULTS: There were 66 280 new users of long-acting insulin analogues and 66 173 new users of NPH insulin. The incidence rate of DR was 101.7 per 1000 person-years (95% CI, 98.7-104.8) for insulin analogues and 93.2 (95% CI, 90.0-96.5) per 1000 person-years for NPH insulin. Compared with the current use of NPH insulin, insulin analogues were not associated with the risk of incident DR (HR 1.04, 95% CI, 0.99-1.09). The adjusted HRs were 0.84 (95% CI, 0.66-1.07) for proliferative DR and 1.02 (95% CI, 0.97-1.08) for non-proliferative DR. CONCLUSIONS: Compared with NPH insulin, long-acting insulin analogues were not associated with the risk of incident DR among patients with type 2 diabetes. This finding provides important reassurance regarding the safety of long-acting insulin analogues with respect to incident DR.

Sodium-glucose cotransporter 2 inhibitors and the risk of venous thromboembolism: A population-based cohort study.

AIMS: The cardiovascular benefits of sodium-glucose cotransporter 2 inhibitors (SGLT2Is) result from their complex impact on coronary and arterial vessels. However, their effect on veins and the risk of venous thromboembolism (VTE) remains unclear. Meta-analysis of trials has suggested no significant change in risk, but observational studies on the topic are scarce. Our objective was to determine if the use of SGLT2Is, compared to the use of dipeptidyl peptidase 4 inhibitors (DPP-4Is), is associated with the risk of VTE among patients with type 2 diabetes. METHODS: Using the Clinical Practice Research Datalink linked to hospitalization and vital statistics databases, we conducted a retrospective cohort study using a prevalent new-user design. SGLT2Is were matched to DPP-4I users on calendar time, diabetes treatment intensity, duration of previous DPP-4I use and time-conditional high-dimensional propensity score. Cox proportional hazard models estimated the hazard ratio (HR) for VTE with SGLT2Is versus DPP-4Is. RESULTS: SGLT2I use was not associated with an increased risk of VTE (HR 0.65, 95% confidence interval [CI] 0.34 to 1.25). This finding was consistent among prevalent (HR 0.47, 95% CI 0.16 to 1.42) and incident (HR 0.75, 95% CI 0.33 to 1.72) new users. CONCLUSIONS: We found that SGLT2Is were not associated with an increased risk of VTE compared to DPP-4Is. Although we observed a numerically decreased risk of VTE with SGLT2Is, estimates were accompanied by wide 95% CIs. Nonetheless, given the morbidity associated with VTE, our results provide some reassurance regarding the safety of SGLT2Is with respect to VTE.

Levothyroxine initiation and the risk of pregnancy loss among pregnant women with subclinical hypothyroidism: An observational study emulating a target trial.

BACKGROUND: While the benefits of levothyroxine are well-established for overt hypothyroidism, they are unclear for subclinical hypothyroidism (SCH) among pregnant women. OBJECTIVE: To estimate the effect of initiation of levothyroxine on pregnancy loss among women with SCH with an emulated target trial using observational data. METHODS: We emulated a target trial using the United Kingdom's Clinical Practice Research Datalink to account for the staggered timing of diagnosis and treatment of SCH and the time of entry of women into prenatal care. We emulated multiple nested trials (at each gestational week) and used an intention-to-treat approach to define levothyroxine use (≥1 prescription in the 7 days prior to trial entry), with eligible users matched to non-users (1:4) on time of diagnosis, gestational week of the first eligible trial and high-dimensional propensity score. Pregnancy losses included spontaneous abortion and stillbirth. A pooled logistic regression model with bootstrap resampling was used to estimate the hazard ratios (HR) and 95% confidence intervals (CI). RESULTS: Based on 159,177 eligible person-trials (5781 women), the matched cohort included 181 initiators and 640 non-initiators of levothyroxine, with 57 pregnancy losses occurring during follow-up. Overall, the mean age of women was 32.2 years (SD 5.4), 25% were obese, 8% had type 2 diabetes and about 50% were nulliparous. After matching, women who initiated levothyroxine versus not had higher thyroid-stimulating levels during pregnancy and were more likely to have a history of hypothyroidism. The cumulative incidence of pregnancy loss was lower in initiators versus non-initiators of levothyroxine. The adjusted HR for pregnancy loss was 0.87 (95% CI 0.22, 1.56). CONCLUSIONS: Although our assessment of the effect of initiation of levothyroxine for SCH in pregnancy precludes any definitive conclusions due to wide confidence intervals, this study illustrates the feasibility of using the target trial emulation framework to examine the effectiveness of medication use in pregnancy.

Immeasurable Time Bias in Self-controlled Designs: Case-crossover, Case-time-control, and Case-case-time-control Analyses.

BACKGROUND: Impact of immeasurable time bias (IMTB) is yet to be examined in self-controlled designs. METHODS: We conducted case-crossover, case-time-control, and case-case-time-control analyses using Korea's healthcare database. Two empirical examples among elderly patients were used: 1) benzodiazepines-hip fracture; 2) benzodiazepines-mortality. For cases, the date of hip fracture diagnosis or death was defined as the index date, and the inherited date of their matched cases for controls or future cases. Exposure was assessed in the 1-30 day (hazard) and 61-90 day (control) windows preceding the index date. A non-missing exposure setting included in- and outpatient prescriptions and the pseudo-outpatient setting included only the outpatients. Conditional logistic regression was done to estimate odds ratios (ORs) with 95% confidence intervals (CIs), where the relative difference in OR among the two settings was calculated to quantify the IMTB. RESULTS: The IMTB had negligible impacts in the hip fracture example in the case-crossover (non-missing exposure setting OR 1.27; 95% CI, 1.12-1.44; pseudo-outpatient setting OR 1.21; 95% CI, 1.06-1.39; magnitude 0.05), case-time-control (OR 1.18; 95% CI, 0.98-1.44; OR 1.13; 95% CI, 0.92-1.38; 0.04, respectively), and case-case-time-control analyses (OR 0.99; 95% CI, 0.80-1.23; OR 0.94; 95% CI, 0.75-1.18; 0.05, respectively). In the mortality example, IMTB had significant impacts in the case-crossover (non-missing exposure setting OR 1.44; 95% CI, 1.36-1.52; pseudo-outpatient setting OR 0.72; 95% CI, 0.67-0.78; magnitude 1.00), case-time-control (OR 1.38; 95% CI, 1.26-1.51; OR 0.68; 95% CI, 0.61-0.76; 1.03, respectively), and case-case-time-control analyses (OR 1.27; 95% CI, 1.15-1.40; OR 0.62; 95% CI, 0.55-0.69; 1.05, respectively). CONCLUSION: Although IMTB had negligible impacts on the drug's effect on acute events, as these are unlikely to be accompanied with hospitalizations, it negatively biased the drug's effect on mortality, an outcome with prodromal phases, in the three self-controlled designs.

The association of long-acting insulin analogue use versus neutral protamine Hagedorn insulin use and the risk of major adverse cardiovascular events among individuals with type 2 diabetes: A population-based cohort study.

AIMS: To compare the risk of cardiovascular outcomes associated with long-acting insulin analogues versus neutral protamine Hagedorn (NPH) insulin among patients with type 2 diabetes. MATERIALS AND METHODS: We conducted a population-based retrospective cohort study using the UK Clinical Practice Research Datalink Aurum, linked with hospitalization and vital statistics data. Patients with type 2 diabetes who initiated basal insulin treatment between 2002 and 2018 were included in the study. Exposure was defined as current use of long-acting insulin analogues or NPH insulin, defined using a time-varying approach. The primary outcome was major adverse cardiovascular events (MACE; a composite endpoint of myocardial infarction, ischaemic stroke and cardiovascular death). We used a marginal structural Cox proportional hazards model to estimate the hazard ratio (HR) and 95% confidence interval (CI) for MACE with current use of long-acting insulin analogues versus NPH insulin, and in secondary analyses, by long-acting insulin molecule. RESULTS: Our cohort included 57 334 patients. A total of 3494 MACE occurred over a mean follow-up of 1.6 years (incidence rate 37.4, 95% CI 36.2 to 38.7 per 1000 person-years). Long-acting insulin analogues were associated with a decreased risk of MACE compared to NPH insulin (HR 0.89, 95% CI 0.83 to 0.96). CONCLUSIONS: Current use of long-acting insulin analogues is associated with a modestly reduced risk of MACE compared to current use of NPH insulin among patients with type 2 diabetes. This study could have important implications for drug plan managers and guideline-writing committees for recommendations of insulin treatment for type 2 diabetes.

5-α reductase inhibitors and the risk of anaemia among men with benign prostatic hyperplasia: A population-based cohort study.

5-α reductase inhibitors (5αRIs) are effective for the treatment of benign prostatic hyperplasia (BPH). However, 5αRIs could lower levels of haemoglobin, increasing the risk of anaemia. The objective of this study was to compare the rate of anaemia between new users of 5αRIs and α-blockers in the UK. METHODS: We conducted a matched, active comparator, new-user cohort study using the Clinical Practice Research Datalink. The study population consisted of men aged ≥40 years with incident BPH who initiated 5αRIs between 1998 and 2019 and were matched 1:1 on propensity score to new users of α-blockers. Anaemia was defined by a measured haemoglobin <130 g/L. We used Cox proportional hazards models to estimate hazard ratios (HRs) and 95% confidence intervals (CIs) for anaemia. RESULTS: Our study cohort included 9429 new users of 5αRIs and 9429 matched new users of α-blockers. Their median durations of follow-up were 136 days (interquartile range: 54-336 d) and 77 days (interquartile range: 58-236 d), respectively. A total of 2865 5αRIs users and 2407 α-blocker users developed incident anaemia, representing rates of 37.3 (95% CI: 33.6-41.3) and 42.0 (95% CI: 38.1-46.2) per 100 person-years, respectively. The use of 5αRIs was not associated with an increased risk of anaemia compared to the use of α-blockers (HR: 0.95, 95% CI: 0.90-1.00). Similarly, we did not observe an increased risk of mild, moderate, or severe anaemia. CONCLUSION: The use of 5αRIs was not associated with an increased risk of anaemia compared to the use of α-blockers among men with BPH.

Utilization and long-term persistence of direct oral anticoagulants among patients with nonvalvular atrial fibrillation and liver disease.

AIMS: We characterized the utilization and long-term treatment persistence of direct oral anticoagulants (DOACs) in patients with nonvalvular atrial fibrillation (NVAF) and liver disease. METHOD: Using the UK Clinical Practice Research Datalink, we assembled a population-based cohort of NVAF patients with liver disease initiating oral anticoagulants between 2011 and 2020. Logistic regression estimated odds ratios (ORs) and 95% confidence intervals (CIs) of the association between patient characteristics and initiation of DOACs vs vitamin K antagonists (VKAs). Cox proportional hazards models estimated hazard ratios (HRs) and 95% CIs of the association between patient characteristics and the switch from VKAs to DOACs vs remaining on VKAs. We also assessed the 5-year treatment persistence with DOACs vs VKAs, and whether ischemic stroke or bleeding preceded treatment discontinuation. RESULTS: Our cohort included 3167 NVAF patients with liver disease initiating DOACs (n = 2247, 71%) or VKAs (n = 920, 29%). Initiators of DOACs were more likely to have prior ischemic stroke (OR 1.44, 95% CI 1.12-1.85) than VKA initiators but less likely to have used antiplatelet agents (OR 0.66, 95% CI 0.53-0.82). Patients switching to DOACs were more likely to have used selective serotonin reuptake inhibitors (HR 1.64, 95% CI 1.13-2.37) than those remaining on VKAs. At 5 years, 31% of DOAC initiators and 9% of VKA initiators remained persistent. Only few patients were diagnosed with ischemic stroke or bleeding prior to treatment discontinuation. CONCLUSION: Most NVAF patients with liver disease initiated treatment with DOACs. Long-term persistence with DOACs was higher than with VKAs but remained relatively low.

Tramadol versus codeine and the short-term risk of cardiovascular events in patients with non-cancer pain: A population-based cohort study.

AIMS: The effect of tramadol on the cardiovascular system is largely unknown. There is concern that, with its multimodal mechanism of action to increase serotonin and norepinephrine levels in the body, it could increase the risk of arterial ischaemia and cardiovascular events. We aimed to compare the short-term risk of cardiovascular events with the use of tramadol to that of codeine among patients with non-cancer pain. METHODS: We conducted a retrospective population-based cohort study using data from the Clinical Practice Research Datalink (CPRD) with new users of tramadol or codeine from April 1998 to March 2017. Exposure was defined using an approach analogous to an intention-to-treat, with a maximum follow-up of 30 days. The primary endpoint was myocardial infarction, and secondary endpoints were unstable angina, ischaemic stroke, coronary revascularization, cardiovascular death and all-cause mortality. Hazard ratios (HRs) were estimated using Cox proportional hazards models, adjusted for high-dimensional propensity score. RESULTS: The final cohort included 123 394 tramadol users and 914 333 codeine users. When tramadol was compared to codeine, the adjusted hazard ratio (HR) of myocardial infarction was 1.00 (95% CI 0.81-1.24). There was also no evidence of elevated risks of unstable angina (0.92; 95% CI 0.67-1.27), ischaemic stroke (0.98; 95% CI 0.82-1.17), coronary revascularization (0.97; 95% CI 0.69-1.38), cardiovascular death (1.07; 95% CI 0.93-1.23) or all-cause mortality (1.03; 95% CI 0.94-1.14) when tramadol was compared to codeine. CONCLUSIONS: Short-term use of tramadol, compared with codeine, was not associated with an increased risk of cardiac events among patients with non-cancer pain.