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.

Stereotactic Radiosurgery for Small Intact Brain Metastasis: A Comparative Evaluation of 3 Different Single Fraction Prescription Doses

PURPOSE/OBJECTIVE(S)

While single-fraction stereotactic radiosurgery (SRS) in the treatment of small brain metastases (SBM, ≤ 2 cm) is well established, prescription dosing varies considerably across institutions and clinical trials. The choice of prescription dose is a delicate balance between local failure (LF) and radiation necrosis (RN) risks. In the modern era, historically-established dosing thresholds may no longer be applicable. To evaluate the impact of prescription dose on outcomes, we performed a comparative analysis of patients with SBM treated with definitive SRS using three different prescriptions, at a single tertiary institution.

MATERIALS/METHODS

Consecutive patients with intact SBM treated with SRS from January 2017 and December 2021 were analyzed. Baseline patient characteristics and dosing parameters were abstracted from the medical record. To limit the integral brain dose when treating multiple brain metastases, the institutional practice was to reduce prescription dose as the total number of lesions increased (i.e., 24 Gy for ≤10 lesions, 22 Gy for 11-20, and 20 Gy for >20). A per lesion analysis, where each lesion was followed from the date of SRS to the last follow-up, was conducted with primary endpoints of LF and RN. Gray's test was used to compare the cumulative incidence of the LF and RN, with death as a competing risk. Factors affecting LF were analyzed using Cox hazard regression analysis.

RESULTS

A total of 1318 SBM in 250 patients received SRS and met the inclusion criteria. The median age was 62 years (range: 18-90), median KPS was 90 (range: 50-100) and 66% were female. The most common primary tumors were lung (55.5%) and breast cancers (26.4%). With a median follow-up of 12 months, 136 (11%) LF in 44 patients and 70 (5.7%) RN events in 46 patients occurred. The actuarial 1-year cumulative rate of LF was lower in lesions treated with 24 Gy (6.4%, 95% CI: 4.7-8.6%) or 22 Gy (5.8%, 95% CI: 3.7-8.7%) compared to 20 Gy (15.4%, 95% CI: 10.9-20.5%) (p<0.01). 22 Gy and 24 Gy prescription doses were associated with a 44% and 52% reduction in risk in LF compared to 20 Gy (HR: 0.56; 95% CI: 0.36-0.9; p = 0.01 and HR: 0.48; 95% CI: 0.31-0.74; p<0.01, respectively). In a subset analysis of radiosensitive tumors, 1-year LF rate was still lower with 24 Gy (7.4%, 95% CI: 5.3-9.9%) and 22 Gy (6.1%, 95% CI: 3.7-9.4%) than 20 Gy (15.7%, 95% CI: 11.2-21%) (p = 0.01). The cumulative 1-year RN rate numerically declined with dose, but was not statistically significantly different, with 3.6% (95% CI: 2.3-5.3%) for 24 Gy, 2.6% (95% CI: 1.3-4.8%) for 22 Gy and 1.4% (95% CI: 0.4-3.7%) for 20 Gy.

CONCLUSION

Patients treated with single fraction SRS to intact SBM were at increased risk of LF with prescription doses of 20 Gy compared to 22-24 Gy, without an increased risk of RN. Even in patients with radiosensitive histologies, higher LF rates were still observed following 20 Gy compared to 22-24 Gy.

A Comparison of Local Failure and Necrosis Following Different Radiosurgery Strategies for Large Brain Metastases

PURPOSE/OBJECTIVE(S)

Large brain metastases (LBMs) are associated with poor local control with single-fraction stereotactic radiosurgery (SRS) alone. Various alternative strategies have been developed, including fractionated SRS (FSRS) and staged SRS (SSRS) for intact LBMs, and resection with postoperative-SRS (postop-SRS) or preoperative-SRS (preop-SRS) for operable LBMs. The objective of this study is to compare local failure (LF) and radiation necrosis (RN) outcomes among these four management strategies to determine the optimal treatment paradigm.

MATERIALS/METHODS

Consecutive patients diagnosed with LBM (≥2 cm in maximum dimension) between July 2017 and January 2022 and treated with one of the aforementioned strategies at a single tertiary institution were evaluated. All immobilization, target contouring, margins, dose- and prescription selection followed pre-defined institutional guidelines. Primary endpoints included LF, symptomatic RN, or a composite endpoint of these two variables. Gray's test was used to compare the cumulative incidence of the LF and the composite endpoint, with death as a competing risk.

RESULTS

A total of 234 LBMs in 188 consecutive patients met the inclusion criteria. The median age was 65 years (range: 31-98), the median KPS was 80 (range: 50-100), and 58% were female. The most common primary tumors were lung (48%) and breast cancer (17%). The median maximum tumor diameter was 3.0 cm (range: 2.0-5.6). 47 (20%) lesions were treated with FSRS, 66 (28%) with SSRS, 74 (32%) with postop-SRS, and 47 (20%) with preop-SRS. With a median follow-up of 12 months, 22 (9%) LF and 11 (5%) RN events occurred. The 6-month and 1-year cumulative incidences of LF for the entire cohort were 5% (95% CI: 3%-9%) and 8% (95% CI: 5%-12%), respectively. The 6-month and 1-year LF rates were 4% (95% CI: 1%-13%) and 8% (95% CI: 3%-20%) for FSRS; 8% (95% CI: 3%-20%) and 8% (95% CI: 3%-20%) for SSRS; 7% (95% CI: 3%-15%) and 8% (95% CI: 3%-16%) for postop-SRS; 0 and 7% (95% CI: 2%-20%) for preop-SRS (p>0.05). The 1-year OS rates were favorable in resected patients (61% for postop-SRS and 82% for preop-SRS) compared to SRS alone strategies (45% for FSRS and 56% for SSRS) (p = 0.004). Similarly, RN events were significantly lower in resected patients treated with either bimodality approach (0 for postop-SRS and 4% for preop-SRS) than SRS standalone strategies (9% for FSRS and 8% SSRS) (p = 0.024). At 12 months, the cumulative probabilities of the composite endpoint were 13% (95% CI: 5%-25%) for FSRS, 15% (95% CI: 7%-25%) for SSRS, 9% (95% CI: 3%-17%) for postop-SRS, and 12% (95% CI: 4%-24%) for preop-SRS and not significantly different between the groups.

CONCLUSION

For medically operable patients with surgically resectable LBMs, a strategy of surgery and SRS, regardless of timing, is associated with favorable local control and reduced risk for RN. For unresected patients, either SSRS or FSRS is associated with similar local control, but slightly higher RN risk. Prospective comparative evaluation is warranted.

Incidence of Aberrant Right Subclavian Artery in General Population

Objective: The existence of an anomalous right subclavian artery is the most significant aortic arch defect. Dysphagia, wheezing, stridor, and other symptoms may occur if this vessel pressures the neighbouring structures. The goal of this study is to find out how common ARSA is based on CT scans of the thorax and neck (plain and contrast). Method: Between January 1st and December 31st, 2020, 1122 patients had CT Thorax/neck scans, and the data were evaluated. The origin of the ARSA, the vessel's path, and the Kommerell diverticulum were all assessed. We looked at the literature to see how important ARSA is in clinical practise. Results: ARSA was found in eight of 1122 patients. All of the ARSAs in these eight individuals began at the posterior part of the aortic arch and travelled via the retroesophageal path to the thoracic outlet. All eight ARSA were found in the front part of the thoracic vertebral bodies, from the first to the fourth. Conclusion: Other clinical symptoms such as dysphagia, dyspnea, retrosternal discomfort, cough, and weight loss must be differentiated from compression of surrounding tissues by an abnormal right subclavian artery.

Stronger inflammatory/cytotoxic T-cell response in women identified by microarray analysis

Women develop chronic inflammatory autoimmune diseases more often than men. The mechanisms causing the increased susceptibility are incompletely understood. Chronic immune stimulation characterizes many autoimmune disorders. We hypothesized that repeated stimulation may cause a different T cell response in women than men. Microarrays were used to compare gene expression in T cells from healthy men and women with and without repeated stimulation. Four days following a single stimulation only 25% of differentially expressed, gender-biased genes were expressed at higher levels in women. In contrast, following restimulation 72% were more highly expressed in women. Immune response genes were significantly over-represented among the genes upregulated in women and among the immune response genes, the inflammatory/cytotoxic effector genes interferon gamma (IFNG), lymphotoxin beta (LTB), granzyme A (GZMA), interleukin-12 receptor beta2 (IL12RB2), and granulysin (GNLY) were among those overexpressed to the greatest degree. In contrast, IL17A was the only effector gene more highly expressed in men. Estrogen response elements were identified in the promoters of half the overexpressed immune genes in women, and in <10% of the male biased genes. The differential expression of inflammatory/cytotoxic effector molecules in restimulated female T cells may contribute to the differences in autoimmune diseases between women and men.

Differential gene expression during terminal erythroid differentiation

Terminal erythroid differentiation in mammals is the process whereby nucleated precursor cells accumulate erythroid-specific proteins such as hemoglobin, undergo extensive cellular and nuclear remodeling, and ultimately shed their nuclei to form reticulocytes, which then become mature erythrocytes in the circulation. Little is known about the mechanisms that enable erythroblasts to undergo such a transformation. We hypothesized that genes involved in these mechanisms were likely expressed at restricted times during the differentiation process and used differential display reverse transcriptase polymerase chain reaction as a first step in identifying such genes. We identified three differentially expressed cDNAs that we termed late erythroblast (LEB) 1-3. None of these cDNAs were previously identified as being expressed in erythroblasts and their patterns of expression indicated they are likely to be involved in the differentiation process. LEB-1 cDNA was derived from the gene A330102K04Rik (approved gene symbol Apoll1), and shares homology with members of the apolipoprotein L family in humans. LEB-3 cDNA was derived from the novel gene D930015E06Rik, that has no known function. LEB-2 cDNA was derived from the gene ranBP16 (approved gene symbol Xpo7), a nuclear exportin. D930015E06Rik mRNA is also strongly expressed in the testis and was localized to a region of the seminiferous tubule where secondary spermatocytes and early spermatids are found, suggesting a role for D930015E06Rik in spermatogenesis as well as terminal erythroid differentiation. We have thus identified three genes not previously described as being expressed in erythroblasts that could be relevant in elucidating mechanisms involved in terminal erythroid differentiation.

A syphilis outbreak: recent trends in infectious syphilis in Birmingham, UK, in 2005 and control strategies

The objective of this study was to identify the demographic characteristics and sexual behaviour associated with primary, secondary and early latent syphilis in Birmingham and its epidemiologic and public health implications. All new patients diagnosed as having infectious syphilis in a genitourinary service in Birmingham in the period from January 2005 to December 2005 were studied retrospectively (history, physical examination, serology) to determine the stage of their disease. During the 12-month period, 69 new cases of primary, secondary and early latent syphilis were diagnosed. Patients were most commonly male (96%), aged between 20 and 44 years, symptomatic (84%) and were white men who had sex with men or Asian/Black Caribbean heterosexual men. Unemployment and having multiple partners were common in infected patients. Based on the results of this study, control measures are being undertaken, using enhanced surveillance, to focus on appropriate health promotion initiatives.