Effects of empagliflozin on progression of chronic kidney disease: a prespecified secondary analysis from the empa-kidney trial

BACKGROUND

Sodium-glucose co-transporter-2 (SGLT2) inhibitors reduce progression of chronic kidney disease and the risk of cardiovascular morbidity and mortality in a wide range of patients. However, their effects on kidney disease progression in some patients with chronic kidney disease are unclear because few clinical kidney outcomes occurred among such patients in the completed trials. In particular, some guidelines stratify their level of recommendation about who should be treated with SGLT2 inhibitors based on diabetes status and albuminuria. We aimed to assess the effects of empagliflozin on progression of chronic kidney disease both overall and among specific types of participants in the EMPA-KIDNEY trial.

METHODS

EMPA-KIDNEY, a randomised, controlled, phase 3 trial, was conducted at 241 centres in eight countries (Canada, China, Germany, Italy, Japan, Malaysia, the UK, and the USA), and included individuals aged 18 years or older with an estimated glomerular filtration rate (eGFR) of 20 to less than 45 mL/min per 1·73 m2, or with an eGFR of 45 to less than 90 mL/min per 1·73 m2 with a urinary albumin-to-creatinine ratio (uACR) of 200 mg/g or higher. We explored the effects of 10 mg oral empagliflozin once daily versus placebo on the annualised rate of change in estimated glomerular filtration rate (eGFR slope), a tertiary outcome. We studied the acute slope (from randomisation to 2 months) and chronic slope (from 2 months onwards) separately, using shared parameter models to estimate the latter. Analyses were done in all randomly assigned participants by intention to treat. EMPA-KIDNEY is registered at ClinicalTrials.gov, NCT03594110.

FINDINGS

Between May 15, 2019, and April 16, 2021, 6609 participants were randomly assigned and then followed up for a median of 2·0 years (IQR 1·5-2·4). Prespecified subgroups of eGFR included 2282 (34·5%) participants with an eGFR of less than 30 mL/min per 1·73 m2, 2928 (44·3%) with an eGFR of 30 to less than 45 mL/min per 1·73 m2, and 1399 (21·2%) with an eGFR 45 mL/min per 1·73 m2 or higher. Prespecified subgroups of uACR included 1328 (20·1%) with a uACR of less than 30 mg/g, 1864 (28·2%) with a uACR of 30 to 300 mg/g, and 3417 (51·7%) with a uACR of more than 300 mg/g. Overall, allocation to empagliflozin caused an acute 2·12 mL/min per 1·73 m2 (95% CI 1·83-2·41) reduction in eGFR, equivalent to a 6% (5-6) dip in the first 2 months. After this, it halved the chronic slope from -2·75 to -1·37 mL/min per 1·73 m2 per year (relative difference 50%, 95% CI 42-58). The absolute and relative benefits of empagliflozin on the magnitude of the chronic slope varied significantly depending on diabetes status and baseline levels of eGFR and uACR. In particular, the absolute difference in chronic slopes was lower in patients with lower baseline uACR, but because this group progressed more slowly than those with higher uACR, this translated to a larger relative difference in chronic slopes in this group (86% [36-136] reduction in the chronic slope among those with baseline uACR <30 mg/g compared with a 29% [19-38] reduction for those with baseline uACR ≥2000 mg/g; ptrend<0·0001).

INTERPRETATION

Empagliflozin slowed the rate of progression of chronic kidney disease among all types of participant in the EMPA-KIDNEY trial, including those with little albuminuria. Albuminuria alone should not be used to determine whether to treat with an SGLT2 inhibitor.

FUNDING

Boehringer Ingelheim and Eli Lilly.

Impact of primary kidney disease on the effects of empagliflozin in patients with chronic kidney disease: secondary analyses of the EMPA-KIDNEY trial

BACKGROUND

The EMPA-KIDNEY trial showed that empagliflozin reduced the risk of the primary composite outcome of kidney disease progression or cardiovascular death in patients with chronic kidney disease mainly through slowing progression. We aimed to assess how effects of empagliflozin might differ by primary kidney disease across its broad population.

METHODS

EMPA-KIDNEY, a randomised, controlled, phase 3 trial, was conducted at 241 centres in eight countries (Canada, China, Germany, Italy, Japan, Malaysia, the UK, and the USA). Patients were eligible if their estimated glomerular filtration rate (eGFR) was 20 to less than 45 mL/min per 1·73 m2, or 45 to less than 90 mL/min per 1·73 m2 with a urinary albumin-to-creatinine ratio (uACR) of 200 mg/g or higher at screening. They were randomly assigned (1:1) to 10 mg oral empagliflozin once daily or matching placebo. Effects on kidney disease progression (defined as a sustained ≥40% eGFR decline from randomisation, end-stage kidney disease, a sustained eGFR below 10 mL/min per 1·73 m2, or death from kidney failure) were assessed using prespecified Cox models, and eGFR slope analyses used shared parameter models. Subgroup comparisons were performed by including relevant interaction terms in models. EMPA-KIDNEY is registered with ClinicalTrials.gov, NCT03594110.

FINDINGS

Between May 15, 2019, and April 16, 2021, 6609 participants were randomly assigned and followed up for a median of 2·0 years (IQR 1·5-2·4). Prespecified subgroupings by primary kidney disease included 2057 (31·1%) participants with diabetic kidney disease, 1669 (25·3%) with glomerular disease, 1445 (21·9%) with hypertensive or renovascular disease, and 1438 (21·8%) with other or unknown causes. Kidney disease progression occurred in 384 (11·6%) of 3304 patients in the empagliflozin group and 504 (15·2%) of 3305 patients in the placebo group (hazard ratio 0·71 [95% CI 0·62-0·81]), with no evidence that the relative effect size varied significantly by primary kidney disease (pheterogeneity=0·62). The between-group difference in chronic eGFR slopes (ie, from 2 months to final follow-up) was 1·37 mL/min per 1·73 m2 per year (95% CI 1·16-1·59), representing a 50% (42-58) reduction in the rate of chronic eGFR decline. This relative effect of empagliflozin on chronic eGFR slope was similar in analyses by different primary kidney diseases, including in explorations by type of glomerular disease and diabetes (p values for heterogeneity all >0·1).

INTERPRETATION

In a broad range of patients with chronic kidney disease at risk of progression, including a wide range of non-diabetic causes of chronic kidney disease, empagliflozin reduced risk of kidney disease progression. Relative effect sizes were broadly similar irrespective of the cause of primary kidney disease, suggesting that SGLT2 inhibitors should be part of a standard of care to minimise risk of kidney failure in chronic kidney disease.

FUNDING

Boehringer Ingelheim, Eli Lilly, and UK Medical Research Council.

Impact of cardiovascular events on primary and hospital care costs: findings from UK Biobank study

Background

Need for primary and secondary healthcare increases following cardiovascular disease (CVD) events but there is no data on comparative increases in costs.

Purpose

To estimate annual primary care and hospital inpatient costs associated with key CVD and other adverse events using the UK Biobank (UKB) individual participant data.

Methods

UKB participants with linked primary care data (192,983 participants) or hospital inpatient episodes data (all 501,807 participants) contributed data to this study. The three categories of primary care services (patient consultations, diagnostic and monitoring tests, prescription medications), and hospital episodes were costed (2020 UK£) using the NHS England reference costs. Annual primary care costs and, separately, annual hospital inpatient costs were modelled as functions of participant characteristics at entry (socio-demographic, clinical, prior diseases) and time-updated first occurrences of myocardial infarction, stroke, coronary revascularization, incident cancer, incident diabetes, vascular death and non-vascular death during follow-up (p-value &lt;0.01 in stepwise covariate selection). One-part generalized linear regression model (GLM) with Poisson distribution and identity link function was used for primary care costs, and two-part model was used for inpatient costs (part 1: logistic regression models probability of incurring costs; part 2: GLM with Poisson distribution and identity link function models costs conditional on incurring any). Separate models were fitted among participants with and without previous CVD at entry into UKB.

Results

Most adverse events were associated with excess primary care and hospital inpatient costs. Compared to people without previous CVD, people with previous CVD had on average larger excess primary care and hospital inpatient costs in years with myocardial infarction, stroke and vascular death; but similar excess costs in years with other events. Among both people without and with previous CVD, the excess annual primary care costs were less than 7% of the excess annual hospital inpatient costs for vascular events (Table). However, following diabetes diagnosis the excess annual primary care costs were higher than the excess annual hospital inpatient costs (Table).

Conclusions

These excess primary and hospital care costs associated with CVD events could inform assessments of interventions and policies to reduce CVD risks in UK.

Funding Acknowledgement

Type of funding sources: Public grant(s) – National budget only. Main funding source(s): UK National Institute for Health Research (NIHR) Health Technology Assessment (HTA) Programme, UK Medical Research Council (MRC), British Heart Foundation

Cost-effectiveness of statin therapy in categories of patients in the UK

Background

Cardiovascular disease (CVD) mortality has declined steadily over the last few decades across Europe and North America.

Purpose

To provide contemporary estimates of long-term effectiveness and cost-effectiveness of statin therapy in different categories of patients in UK.

Methods

The CTT-UKB micro-simulation model, developed using the Cholesterol Treatment Trialists' Collaboration data (CTT: 118,000 participants; 5 years follow-up), and calibrated in the UK Biobank cohort (UKB: 502,000 participants; 9 years follow-up). The model integrates parametric risk equations for incident myocardial infarction, stroke, coronary revascularization, diabetes, cancer and vascular and nonvascular death, and projects annually these endpoints and survival using patient characteristics at entry. UKB data and linked primary and hospital care data informed healthcare costs in the model (2020 UK£); 2021 UK NHS Drug Tariff informed statin costs (atorvastatin 40mg at £1.22 and 80mg at £1.68 per 28 tablets); and Health Survey for England data informed health-related quality of life in the model. Previous CTT meta-analysis, atorvastatin dose-response randomized trials, and further meta-analyses of statin trials and cohort studies informed effects of 40mg/80mg atorvastatin therapy daily on rates of incident myocardial infarction, stroke, coronary revascularization, vascular death, diabetes, myopathy and rhabdomyolysis.

The model was used to project gains in quality-adjusted life years (QALYs) and additional cost per QALY with lifetime use of atorvastatin 40mg or 80mg daily in categories of UKB participants by sex, age at statin initiation (40–49; 50–59 and 60–70 years), and 10-year CVD risk (QRISK3 risk (%): &lt;5; 5–10, 10–15, 15–20, ≥20). Further scenarios explored effects of 5-year delay of statin initiation in people under 45 years of age or stopping statin therapy at 80 years of age.

Results

Across men and women in categories by age and CVD risk, lifetime use of atorvastatin 40mg daily was associated with increases in survival by 0.44–1.69 years (0.28–1.02 QALYs), and atorvastatin 80mg daily with increases in survival of 0.45–1.87 years (0.32–1.13 QALYs; Figure 1) with gains larger among participants at higher CVD risk. Both atorvastatin 40mg and 80mg doses were in the range of cost-effective treatments with incremental cost per QALY gained with atorvastatin 40mg daily versus no statin therapy below £7200/QALY and with atorvastatin 80mg vs 40mg daily below £16000/QALY (Figure 2) across all patient categories studied. Compared to lifetime statin therapy, stopping therapy at 80 years of age substantially reduced benefits and was not cost-effective in any patient category studied. Similarly, compared to immediate initiation, 5-year delay of statin therapy in 40–45 years old patients was not a cost-effective.

Conclusions

In the UK, statin therapy remains highly cost-effective across men and women 40–70 years old, including those at 10-year CVD risk &lt;5%.

Funding Acknowledgement

Type of funding sources: Public grant(s) – National budget only. Main funding source(s): UK National Institute for Health Research (NIHR) Health Technology Assessment (HTA) Programme, UK National Institute for Health Research (NIHR) Health Technology Assessment (HTA) Programme, UK Medical Research Council (MRC), British Heart Foundation

Benefit accrual with cardiovascular disease prevention and effects of discontinuation: a modelling study

Background

Statin therapy reduces rates of heart attacks and strokes and improves survival in people at increased cardiovascular disease (CVD) risk. However, there is some uncertainty when to start and how long to persist with statin therapy so as to optimise benefits.

Purpose

To project the accrual of benefit with statin therapy in population groups by age at therapy initiation using a newly developed micro-simulation model.

Methods

Participants without previous CVD (N=44,412) and with previous CVD (N=13,061) at entry were randomly selected from the UK Biobank cohort, ensuring sufficient representation in respective categories by age, LDL cholesterol, diabetes and 10-year CVD risk categories (QRISK3 score, for those without previous CVD only). The CTT-UKB model, a CVD micro-simulation model [1], was used to predict subsequent survival and quality-adjusted life years (QALYs) of the participants using their characteristics at entry. Treatment with atorvastatin 40mg daily was used as an example to illustrate the effect of the therapy compared to no such therapy. Scenarios include: (1) lifelong preventive therapy, (2) preventive therapy stopped at 80 years of age, and (3) delayed initiation of preventive therapy by 5 years in participants under 45 years of age.

Results

Statin treatment benefits, measured in QALYs gained, accrue over lifetime. The majority of benefits accrue later in life. Men accumulate larger benefits and earlier than women (Figure 1A). The pattern of benefits accrual is similar for participants with and without previous CVD (data not shown). The higher the participants' CVD risk, the larger and earlier the benefits, with younger participants accruing larger benefits (Figure 1B). Compared with lifelong prevention, stopping treatment at 80 years of age leads to large reductions in overall benefits, especially in women and those at lower CVD risk. For example, compared to lifelong therapy, people without previous CVD who initiate therapy in their 50s, would lose 47% of QALYs benefit (if men), 66% (if women), 73% (if with CVD risk &lt;5%), and 35% (if with CVD risk ≥20%), respectively, if they stop treatment when they reach 80 years of age. Five-year delay of statin therapy initiation in people under 45 years of age reduces their benefits by about 4% on average, though the loss is somewhat larger in people at higher CVD risk (Figure 2).

Conclusion

Benefits from lifelong cardiovascular prevention accrue over peoples' lifespan with large share of benefits accruing at older age. Stopping treatment earlier substantially reduces benefits.

Funding Acknowledgement

Type of funding sources: Public grant(s) – National budget only. Main funding source(s): UK NationalInstitute for Health Research (NIHR) Health Technology Assessment (HTA) Programme, UK Medical Research Council (MRC), and British Heart Foundation

A model of lifetime health outcomes in cardiovascular disease based on clinical trials and large cohorts

Background and purpose

Cardiovascular disease (CVD) risk of individuals depends on their socio-demographic characteristics, clinical risk factors, and treatments, and strongly influences their quality of life and survival. Individual-based long-term disease models, which aim to more accurately calculate the lifetime consequences, can help to target treatments, develop disease management programmes, and assess the value of new therapies. We present a new micro-simulation CVD model.

Methods

This micro-simulation model was developed using individual participant data from the Cholesterol Treatment Trialists' collaboration (CTT: 118,000 participants; 15 trials) and calibrated (with added socioeconomic deprivation, ethnicity, physical activity, mental illness, cancer and incident diabetes) in the UK Biobank cohort (UKB: 502,000 participants). Parametric survival models estimated risks of key endpoints (myocardial infarction (MI), stroke, coronary revascularisation (CRV), diabetes, cancer and vascular (VD) and nonvascular death (NVD) using participants' age, sex, ethnicity, physical activity, socioeconomic deprivation, smoking history, lipids, blood pressure, creatinine, previous cardiovascular diseases, diabetes, mental illness and cancer at entry and non-fatal incidents of the key endpoints during follow-up. The model integrates the risk equations and enables annual projection of endpoints and survival over individuals' lifetimes. The model was used to project remaining life expectancy across UK Biobank participants.

Results

Nonfatal cardiovascular events and age were the major determinants of CVD risk and, together with incident diabetes and cancer, of individuals' survival. The cumulative incidence of the key endpoints predicted by the CTT-UKB model corresponded well to their observed incidence in the UK Biobank cohort, overall (Figure 1) and in categories of participants by age, sex, prior CVD and CVD risk. Predicted remaining life expectancy across UK Biobank participants without history of CVD ranged between 22 and 43 years in men and between 24 and 46 years in women, depending on their age and CVD risk (Figure 2). Among UK Biobank participants with history of CVD, depending on their age, predicted remaining life expectancy ranged from 20 to 32 years in men and from 26 to 38 years in women.

Conclusion

This new lifetime CVD model accurately predicts morbidity and mortality in a large UK population cohort. It will be made available to provide individualised projections of expected lifetime health outcomes and benefits of treatments.

Funding Acknowledgement

Type of funding sources: Public grant(s) – National budget only. Main funding source(s): UK National Institute for Health Research (NIHR) Health Technology Assessment (HTA) Programme, UK Medical Research Council (MRC), British Heart Foundation Figure 1. Predicted (in black) versus observed (95% CI; in red) incidence of major clinical outcomes in the UK Biobank.Figure 2. Predicted remaining life expectancy of participants in UK Biobank cohort, by age and CVD risk or previous CVD at entry. QRISK, a 10-year CVD risk scoring algorithm for people without previous CVD, recommended for use in the UK National Health Service.

Effect on non-vascular outcomes of lowering LDL cholesterol in patients with chronic kidney disease: results from the Study of Heart and Renal Protection

Background

Reducing LDL cholesterol (LDL-C) with statin-based therapy reduces the risk of major atherosclerotic events among patients with chronic kidney disease (CKD), with no evidence of an excess risk of cancer or death from any non-vascular cause. However, non-randomized data have suggested that statin therapy may have effects (both adverse and beneficial) on particular non-vascular conditions that do not cause death.

Methods

The Study of Heart and Renal Protection (SHARP) randomized patients with CKD to simvastatin 20 mg plus ezetimibe 10 mg (simvastatin/ezetimibe) daily versus matching placebo. Participants were followed up at least 6 monthly and all post-randomization serious adverse events (SAEs) were recorded. This supplementary analysis reports the effects of treatment on non-vascular SAEs, overall, by system of disease, by baseline characteristics, and by duration of follow-up.

Results

During a median of 4.9 years follow-up, similar numbers of participants in the two groups experienced at least one non-vascular SAE (3551 [76.4%] simvastatin/ezetimibe vs 3537 [76.6%] placebo; risk ratio [RR] 0.99, 95% confidence interval [CI] 0.95–1.04). There was no good evidence of any significant effect of simvastatin/ezetimibe on SAEs attributed to any particular nonvascular disease system (of 43 comparisons, only 3 yielded an uncorrected p value < 0.05, of which the smallest was p = 0.02). The relative risk of any nonvascular SAE did not vary significantly among particular prognostic subgroups or by duration of follow-up.

Conclusions

In the SHARP trial, allocation to simvastatin/ezetimibe combination therapy was not associated with any significant non-vascular hazard.

Trials registration

SHARP was retrospectively registered after the first participant was enrolled in 2003 at ISRCTN (ISRCTN54137607 on 31 January 2005: http://www.isrctn.com/ISRCTN54137607) and ClinicalTrials.gov (NCT00125593 on 29 July 2005: https://clinicaltrials.gov/ct2/show/NCT00125593).

Electronic supplementary material

The online version of this article (doi:10.1186/s12882-017-0545-2) contains supplementary material, which is available to authorized users.

Protocol for analyses of adverse event data from randomized controlled trials of statin therapy

The Cholesterol Treatment Trialists' (CTT) Collaboration was originally established to conduct individual participant data meta-analyses of major vascular events, cause-specific mortality, and site-specific cancers in large, long-term, randomized trials of statin therapy (and other cholesterol-modifying treatments). The results of the trials of statin therapy and their associated meta-analyses have shown that statins significantly reduce the risk of major vascular events without any increase in the risk of nonvascular causes of death or of site-specific cancer, but do produce small increases in the incidence of myopathy, diabetes, and, probably, hemorrhagic stroke. The CTT Collaboration has not previously sought data on other outcomes, and so a comprehensive meta-analysis of all adverse events recorded in each of the eligible trials has not been conducted. This protocol prospectively describes plans to extend the CTT meta-analysis data set so as to provide a more complete understanding of the nature and magnitude of any other effects of statin therapy.

Spontaneous intracerebral hemorrhage following carotid endarterectomy. Experience of 328 operations from 1983-1988

In a consecutive series of 328 carotid endarterectomies there were two cases of postoperative intracerebral hemorrhage. The patients with transient ischemic attacks and subsequent major cerebral infarction had repair of their very tight carotid stenosis. Each developed intracerebral hemorrhage after a symptom free interval and hypertension was uncontrolled during the postoperative period. Hypertension is a significant complication of carotid endarterectomy and may be a prominent factor in the development of intracerebral hemorrhage after carotid endarterectomy. Also defective cerebrovascular autoregulation in chronic ischemic brain regions may predispose patients to intracerebral hemorrhage.

[Epidural hematoma following peridural anesthesia]

Complications of epidural anesthesia are uncommon, but lesions are possible without technical failure. Neurological symptoms increase progressively with spinal cord compression; early recognition and treatment are imperative. Operative decompression is in most cases the only therapeutic option. This case report aims to call attention to the possibility of epidural hematoma following epidural anesthesia.

Risk factors of recurrent disc herniation

The causes of 100 disc herniation reoperations are analyzed and discussed in a review: we find a recurrence of disc herniation at the same level in 62% of the reoperated cases, a pseudorecurrence in 24% and a closely connected nerve route in 14%. We reoperated on 44% within the first two years and on 69% within the first five years. The interval between the operations is longer, when there is a short painfree interval following surgery and also a long history of pre-operative symptoms. The variables of risk of prolapse recurrence are recorded as a risk score. Retrospectively, 64% belonged to a risk group according to this score. The correlation between operation intervals and scores show, that patients with a short interval have high scores.

[Etiology of the recurrence of lumbar intervertebral disk displacement]

In a review for reasons of 100 disc prolapses reoperations we found in 62% a recurrence of disc prolapse at the same level, in 24% a recurrence at a different level, whereas in 14% we found that the nerve route was closely connected. We reoperated 44% in the first two years and 69% in the first five years. The time between the operations was prolonged if there was a short period of time for relief of pain after operation and a long period of preoperative symptoms. The variables of risk of a disk prolapse recurrence are recorded in a risk score, in which 64% of the patients belonged retrospectively to a risk group. The correlation between operation interval and score points showed that patients with short interval had high score ratings.