Intersection of Race, Rurality, and Income in Defining Access to Minimally Invasive Lung Surgery.

BACKGROUND: Race is a potent influencer of healthcare access. Geography and income may exert equal or greater influence on patient outcomes. We sought to define the intersection of race, rurality, and income and their influence on access to minimally invasive lung surgery in Medicare beneficiaries. METHODS: Medicare and Medicaid Services data were used to evaluate patients with lung cancer who underwent right upper lobectomy, via open, robotic-assisted (RATS), or video-assisted thoracic surgery (VATS) between 2018 and 2020. International Classification of Diseases 10th edition was used to define diagnoses and procedures. We excluded sub-lobar, segmental, wedge, bronchoplastic, or reoperative patients with non-malignant or metastatic disease or a history of neoadjuvant chemotherapy. Risk adjustment was performed using inverse probability of treatment weighting (IPTW) propensity scores with generalized linear models and Cox Proportional Hazards models. RESULTS: The cohort comprised 13,404 patients, 4,291 (32.1%) open, 4,317 (32.2%) RATS, and 4,796 (35.8%) VATS. Black/Urban patients had significantly higher RATS and VATS rates (p<0.001), higher long-term survival (p=0.007), fewer open resections (p<0.001), and lower overall mortality (p=0.007). Low-income Black/Urban patients had higher RATS (p=0.002), VATS (p<0.001), higher long-term survival (p=0.005), fewer open resections (p<0.001), and lower overall mortality compared to rural white patients. (p=0.005). CONCLUSIONS: Rural white populations living close to the federal poverty line may suffer a burden of disparity traditionally observed among poor Black people. This suggests a need for health policies that extend services to impoverished, rural areas to mitigate social determinants of health.

Predictors of Occlusion after Carotid Stenting.

BACKGROUND: Carotid artery stent (CAS) occlusion is a rare complication not well studied. We used a national dataset to assess real world CAS experience to determine the rate of stent occlusion. The purpose of this study was to 1) Identify risk factors associated with CAS occlusion on long-term follow-up (LTFU) and 2) Determine the adjusted odds of death/transient ischemic attack (TIA)/stroke (cerebrovascular accident (CVA)) in patients with occlusion. METHODS: The national Vascular Quality Initiative CAS dataset (2016-2021) comprised the sample. The primary endpoint was occlusion on LTFU (9-21 months postoperatively as defined by the Vascular Quality Initiative LTFU dataset) with secondary endpoint examining a composite of death/TIA/CVA. Descriptive analyses used chi-square and Wilcoxon tests for categorical and continuous variables respectively. Adjustment variables were selected a priori based on clinical expertise and univariate analyses. Multivariable logistic regression was used to model the odds of occlusion and the odds of death/TIA/CVA. Generalized estimating equations accounted for center level variation. RESULTS: During the study period, 109 occlusions occurred in 12,143 cases (0.9%). On univariate analyses, symptomatic indication, prior stroke, prior neck radiation, lesion calcification (>50%), stenosis (>80%), distal embolic protection device (compared to flow reversal), balloon size, >1 stent and current smoking at time of LTFU were predictive for occlusion. Age ≥ 65, coronary artery disease (CAD), elective status, preoperative statin, preoperative and discharge P2Y12 inhibitor, use of any protection device intraoperatively and protamine were protective. On multivariable analyses, age ≥ 65, CAD, elective status and P2Y12 inhibitor on discharge were protective for occlusion, while patients with prior radiation and those taking P2Y12 inhibitor on LTFU were at increased odds. The adjusted odds of death/TIA/CVA in patients with occlusion on LTFU were 6.05; 95% confidence interval: 3.61-10.11, P < 0.0001. CONCLUSIONS: This study provides an in-depth analysis of predictors for CAS occlusion on LTFU. On univariate analyses, variables related to disease severity (urgency, degree of stenosis, nature of lesion) and intraoperative details (balloon diameter, >1 stent) were predictive for occlusion. These variables were not statistically significant after risk adjustment. On multivariable analyses, prior neck radiation was strongly predictive of occlusion. Elective status, patient age ≥ 65, CAD, and P2Y12 inhibitor upon discharge (but not on LTFU) were protective for occlusion. Additionally, patients who developed occlusion had high odds for death/TIA/CVA. These findings provide important data to guide clinical decision-making for carotid disease management, particularly identifying high-risk features for CAS occlusion. Closer postoperative follow-up and aggressive risk factor modification in these patients may be merited.

Comparison of direct oral anticoagulants and warfarin in chronic limb-threatening ischemia.

OBJECTIVE: The role of direct oral anticoagulants (DOACs) in chronic limb-threatening ischemia after revascularization is unknown. Current evidence-based guidelines do not provide clear guidance on the role of anticoagulation or the selection of anticoagulant. Current practice is highly varied and based on provider and patient preference. The purpose of this study was to measure the impact of different anticoagulants on the incidence of major adverse limb events (MALEs) after revascularization for chronic limb-threatening ischemia, major adverse cardiovascular events (MACEs), all-cause mortality, and hospitalization for major bleeding events. METHODS: This was a single-center, observational, retrospective cohort study. Subjects were eligible if they were 18 years or older; underwent endovascular or open revascularization for chronic limb-threatening ischemia, rest pain, or tissue loss; and were subsequently prescribed apixaban, rivaroxaban, or warfarin. The primary end point was the incidence of MALEs, including above-ankle amputation or major index-limb reintervention, within 1 year of index event. Secondary end points included the rate of all-cause mortality, MACEs, and incidence of International Society on Thrombosis and Haemostasis (ISTH) major bleeding. RESULTS: From January 1, 2017, to September 20, 2022, 141 patients met the inclusion and exclusion criteria and were reviewed. The median age was 67 years, with 92 patients prescribed apixaban or rivaroxaban and 49 patients prescribed warfarin. Of these, 42 patients were prescribed triple antithrombotic therapy, 88 dual antithrombotic therapy, and 13 anticoagulant monotherapy. The primary outcome of 1-year MALEs occurred in 36.7% of the warfarin group and 33.7% of the DOAC group (relative risk [RR], 1.09; 95% CI, 0.53-2.25; P = .72). Secondary outcomes of 1-year MACEs (10.2% vs 4.3%; RR, 2.35; 95% CI, 0.60-9.18; P = .18) and 1-year all-cause mortality (26.5% vs 16.3%; RR, 1.63; 95% CI, 0.70-3.78; P = .15) did not differ between the groups. The secondary safety outcome of 1-year ISTH major bleeding occurred in 16.3% of the warfarin group and 4.3% of the DOAC group (RR, 3.76; 95% CI, 1.07-13.19; P = .015). CONCLUSIONS: In patients with chronic limb-threatening ischemia who were revascularized and prescribed anticoagulation with apixaban, rivaroxaban, or warfarin on discharge, no difference in MALEs, MACEs, or all-cause mortality was found. However, 1-year admissions for ISTH major bleeding were significantly higher among patients prescribed warfarin. A randomized trial may confirm these findings.

Mechanism of Increased LDL (Low-Density Lipoprotein) and Decreased Triglycerides With SGLT2 (Sodium-Glucose Cotransporter 2) Inhibition.

Objective- SGLT2 (sodium-glucose cotransporter 2) inhibition in humans leads to increased levels of LDL (low-density lipoprotein) cholesterol and decreased levels of plasma triglyceride. Recent studies, however, have shown this therapy to lower cardiovascular mortality. In this study, we aimed to determine how SGLT2 inhibition alters circulating lipoproteins. Approach and Results- We used a mouse model expressing human CETP (cholesteryl ester transfer protein) and human ApoB100 (apolipoprotein B100) to determine how SGLT2 inhibition alters plasma lipoprotein metabolism. The mice were fed a high-fat diet and then were made partially insulin deficient using streptozotocin. SGLT2 was inhibited using a specific antisense oligonucleotide or canagliflozin, a clinically available oral SGLT2 inhibitor. Inhibition of SGLT2 increased circulating levels of LDL cholesterol and reduced plasma triglyceride levels. SGLT2 inhibition was associated with increased LpL (lipoprotein lipase) activity in the postheparin plasma, decreased postprandial lipemia, and faster clearance of radiolabeled VLDL (very-LDL) from circulation. Additionally, SGLT2 inhibition delayed turnover of labeled LDL from circulation. Conclusions- Our studies in diabetic CETP-ApoB100 transgenic mice recapitulate many of the changes in circulating lipids found with SGLT2 inhibition therapy in humans and suggest that the increased LDL cholesterol found with this therapy is because of reduced clearance of LDL from the circulation and greater lipolysis of triglyceride-rich lipoproteins. Most prominent effects of SGLT2 inhibition in the current mouse model were seen with antisense oligonucleotides-mediated knockdown of SGLT2.

Factors during training which predict future use of minimally invasive thoracic surgery.

BACKGROUND: While minimally invasive thoracic surgery (MIS) has increased nationwide over the years, most patients undergoing lung and esophageal resections still undergo an open approach. We performed a national survey to analyze factors associated with a propensity to perform MIS after completing a cardiothoracic training program. MATERIALS AND METHODS: Cardiothoracic surgery trainees in 2 or 3-year programs from 2010 to 2016 were sent an online survey regarding the numbers and types of cases performed during training and current practice patterns as attending surgeons. Comfort level with MIS was also assessed. Responses were recorded and analyzed using SPSS. RESULTS: One hundred thirty-six trainees responded, with a mean of 121 lobectomies (30-250) and 40 esophagectomies (8-110) performed during training. Mean minimally invasive lobectomy and esophagectomy rates during training were 53% and 30% respectively. A greater ratio of MIS procedures performed during training correlated with a higher rate performed as an attending (lobectomies, p = 0.04; esophagectomies, p = 0.01) and a greater comfort level with performing these procedures (lobectomies, p = 0.01 and esophagectomies, p < 0.01). CONCLUSIONS: Based on these results, performing a greater ratio of minimally invasive lobectomies and esophagectomies during fellowship training increases the likelihood of performing them as an attending.

Knee Injuries in American Football: An Epidemiological Review.

Football has the highest injury rate amongst popular American sports. Of those injuries that end seasons or careers, the knee is the most common culprit. This is of particular concern because knee injuries are most common in football. This article reviews 4 of the most common knee injuries in American football, with emphasis on epidemiology, risk factors, and treatment outcomes. The injuries reviewed are tears of the anterior cruciate ligament, medial collateral ligament, medial patellofemoral ligament, and posterior cruciate ligament.

Canagliflozin: a sodium glucose co-transporter 2 inhibitor for the treatment of type 2 diabetes mellitus.

The sodium glucose co-transporter 2 (SGLT2) inhibitor canagliflozin is a novel treatment option for adults with type 2 diabetes mellitus (T2DM). In patients with hyperglycemia, SGLT2 inhibition lowers plasma glucose levels by reducing the renal threshold for glucose (RTG ) and increasing urinary glucose excretion (UGE). Increased UGE is also associated with a mild osmotic diuresis and net caloric loss, which can lead to reductions in body weight and blood pressure (BP). After promising results from preclinical and phase I/II studies, the efficacy and safety of canagliflozin was evaluated in a comprehensive phase III development program in over 10,000 patients with T2DM on various background therapies. Canagliflozin improved glycemic control and provided reductions in body weight and BP versus placebo and active comparators in studies of up to 2 years' duration. Canagliflozin was generally well tolerated, with higher incidences of adverse events (AEs) related to the mechanism of action, including genital mycotic infections and AEs related to osmotic diuresis. Results from the preclinical and clinical studies led canagliflozin to be the first-in-class SGLT2 inhibitor approved in the United States, and support canagliflozin as a safe and effective therapeutic option across a broad range of patients with T2DM.

Effect of canagliflozin, a sodium glucose co-transporter 2 inhibitor, on the pharmacokinetics of oral contraceptives, warfarin, and digoxin in healthy participants.

OBJECTIVE: Drug-drug interactions between canagliflozin, a sodium glucose co-transporter 2 inhibitor approved for the management of type-2 diabetes mellitus, and an oral contraceptive (OC), warfarin, and digoxin were evaluated in three phase 1 studies in healthy participants. METHODS: All studies were open-label; study 1 included a fixed-sequence design, and studies 2 and 3 used a crossover design. Regimens were: study 1: OC (levonorgestrel (150 µg) + ethinyl estradiol (30 µg))/day (day 1), canagliflozin 200 mg/day (days 4 - 8), and canagliflozin with OC (day 9); study 2: canagliflozin 300 mg/day (days 1 - 12) with warfarin 30 mg/day (day 6) in period 1, and only warfarin 30 mg/day (day 1) in period 2, or vice versa; study 3: digoxin alone (0.5 mg/day (day 1) + 0.25 mg/day (days 2 - 7)) in period 1, and with canagliflozin 300 mg/day (days 1 - 7) in period 2, or vice versa. Pharmacokinetics (PK) were assessed at prespecified intervals; OC: days 1 and 9, canagliflozin: days 8 - 9 (study 1); warfarin: days 6 (period 1) and 1 (period 2) (study 2); and digoxin: days 5 - 7 (periods 1 and 2) (study 3). Warfarin's pharmacodynamics (PD; International Normalized Ratio (INR)) was assessed on days 6 (period 1) and 1 (period 2). RESULTS: Canagliflozin increased the plasma exposure of OC (maximum plasma concentration (Cmax): 22%, area under the curve (AUC): 6%) and digoxin (Cmax: 36%, AUC: 20%); but did not alter warfarin'€™s PK and PD. No clinically relevant safety findings (including hypoglycemia) were noted. CONCLUSION: Canagliflozin can be coadministered with OC, warfarin, or digoxin without dose adjustments. All treatments were well-tolerated.

Effects of rifampin, cyclosporine A, and probenecid on the pharmacokinetic profile of canagliflozin, a sodium glucose co-transporter 2 inhibitor, in healthy participants.

OBJECTIVE: Canagliflozin, a sodium-glucose co-transporter 2 inhibitor, approved for the treatment of type-2 diabetes mellitus (T2DM), is metabolized by uridine diphosphate-glucuronosyltransferases (UGT) 1A9 and UGT2B4, and is a substrate of P-glycoprotein (P-gp). Canagliflozin exposures may be affected by coadministration of drugs that induce (e.g., rifampin for UGT) or inhibit (e.g. probenecid for UGT; cyclosporine A for P-gp) these pathways. The primary objective of these three independent studies (single-center, open-label, fixed-sequence) was to evaluate the effects of rifampin (study 1), probenecid (study 2), and cyclosporine A (study 3) on the pharmacokinetics of canagliflozin in healthy participants. METHODS: Participants received; in study 1: canagliflozin 300 mg (days 1 and 10), rifampin 600 mg (days 4-12); study 2: canagliflozin 300 mg (days 1-17), probenecid 500 mg twice daily (days 15-17); and study 3: canagliflozin 300 mg (days 1-8), cyclosporine A 400 mg (day 8). Pharmacokinetics were assessed at prespecified intervals on days 1 and 10 (study 1); on days 14 and 17 (study 2), and on days 2-8 (study 3). RESULTS: Rifampin decreased the maximum plasma canagliflozin concentration (Cmax) by 28% and its area under the curve (AUC) by 51%. Probenecid increased the Cmax by 13% and the AUC by 21%. Cyclosporine A increased the AUC by 23% but did not affect the Cmax. CONCLUSION: Coadministration of canagliflozin with rifampin, probenecid, and cyclosporine A was well-tolerated. No clinically meaningful interactions were observed for probenecid or cyclosporine A, while rifampin coadministration modestly reduced canagliflozin plasma concentrations and could necessitate an appropriate monitoring of glycemic control.

Effect of canagliflozin, a sodium glucose co-transporter 2 inhibitor, on C-peptide kinetics.

Canagliflozin, a sodium glucose co-transporter 2 inhibitor, improves indices of ß-cell function estimated based on circulating C-peptide and glucose concentrations (e.g., Homeostasis Model Assessment [HOMA2-%B], meal tolerance test-based indices). However, use of these ß-cell function indices assumes C-peptide kinetics are not altered by canagliflozin. This 2-period crossover study assessed the effect of a single canagliflozin 300-mg dose on C-peptide kinetics in 10 healthy participants. Two hours after receiving canagliflozin or placebo, participants received intravenous somatostatin infusion to suppress endogenous C-peptide secretion and 1 hour later received a bolus injection of synthetic human C-peptide 150 µg. Serum C-peptide was measured over 3 hours and urinary glucose and C-peptide excretion were measured. C-peptide kinetic parameters, including total clearance (CLtotal ) and renal clearance (CLrenal ), were calculated. Serum C-peptide profiles were similar following canagliflozin or placebo treatment. C-peptide CLtotal was slightly lower with canagliflozin versus placebo (mean (SD) of 190 (37) vs. 197 (30) mL/min; canagliflozin/placebo ratio [90% CI] = 96.1% [93.0%; 99.3%]). Other kinetic parameters, including CLrenal , were generally similar between treatments. Results indicate canagliflozin 300 mg does not meaningfully alter C-peptide clearance or other kinetic parameters; therefore, C-peptide-based measurements of insulin secretion are appropriate for assessing ß-cell function in canagliflozin-treated participants.

Effect of food on the pharmacokinetics of canagliflozin, a sodium glucose co-transporter 2 inhibitor, and assessment of dose proportionality in healthy participants.

Canagliflozin, an orally active inhibitor of sodium glucose co-transporter 2, is approved for the treatment of type-2 diabetes mellitus. The effect of food on the pharmacokinetics of 300 mg canagliflozin, and dose proportionality of 50, 100, and 300 mg canagliflozin, were evaluated, in two studies, in healthy participants. Study 1 used a randomized, 2-way crossover design: canagliflozin 300 mg/day was administered under fasted (Period-1) and fed (Period-2) conditions or vice versa. Study 2 was a 3-way crossover: participants were randomized to receive three single-doses of canagliflozin (50, 100, and 300 mg), one in each period. In both studies, treatment periods were separated by washout intervals of 10-14 days, and pharmacokinetics assessed up to 72 hours postdose of each treatment period. No clinically relevant food effects on canagliflozin exposure parameters were observed: 90% confidence intervals (CIs) for the fed/fasted geometric mean ratios of AUC∞ (ratio: 100.51; 90% CI: 89.47-112.93) and Cmax (ratio: 108.09; 90% CI: 103.45-112.95) were entirely within bioequivalence limits (80-125%). Plasma canagliflozin exposures were dose-proportional as the 90% CI of the slope of the regression line for dose-normalized AUC∞ and Cmax fell entirely within the prespecified limits of -0.124 to 0.124. No clinically significant safety issues were noted, and canagliflozin was generally well-tolerated.

Absolute oral bioavailability and pharmacokinetics of canagliflozin: A microdose study in healthy participants.

Absolute oral bioavailability of canagliflozin was assessed by simultaneous oral administration with intravenous [(14) C]-canagliflozin microdose infusion in nine healthy men. Pharmacokinetics of canagliflozin, [(14) C]-canagliflozin, and total radioactivity, and safety and tolerability were assessed at prespecified timepoints. On day 1, single-dose oral canagliflozin (300 mg) followed 105 minutes later by intravenous [(14) C]-canagliflozin (10 µg, 200 nCi) was administered. After oral administration, the mean (SD) Cmax of canagliflozin was 2504 (482) ng/mL at 1.5 hours, AUC∞ 17,375 (3555) ng.h/mL, and t1/2 11.6 (0.70) hours. After intravenous administration, the mean (SD) Cmax of unchanged [(14) C]-canagliflozin was 17,605 (6901) ng/mL, AUC∞ 27,100 (10,778) ng.h/mL, Vdss 83.5 (29.2) L, Vdz 119 (41.6) L, and CL 12.2 (3.79) L/h. Unchanged [(14) C]-canagliflozin and metabolites accounted for about 57% and 43% of the plasma total [(14) C] radioactivity AUC∞ , respectively. For total [(14) C] radioactivity, the mean (SD) Cmax was 15,981 (2721) ng-eq/mL, and AUC∞ 53,755 (15,587) ng-eq.h/mL. Renal (34.5% in urine) and biliary (34.1% in feces) excretions were the major elimination pathways for total [(14) C] radioactivity. The absolute oral bioavailability of canagliflozin was 65% (90% confidence interval: 55.41; 76.07). Overall, oral canagliflozin 300 mg coadministered with intravenous [(14) C]-canagliflozin (10 µg) was generally well-tolerated in healthy men, with no treatment-emergent adverse events.

Pharmacodynamic effects of canagliflozin, a sodium glucose co-transporter 2 inhibitor, from a randomized study in patients with type 2 diabetes.

INTRODUCTION: This randomized, double-blind, placebo-controlled, single and multiple ascending-dose study evaluated the pharmacodynamic effects and safety/tolerability of canagliflozin, a sodium glucose co-transporter 2 inhibitor, in patients with type 2 diabetes. METHODS: Patients (N = 116) discontinued their antihyperglycemic medications 2 weeks before randomization. Patients received canagliflozin 30, 100, 200, or 400 mg once daily or 300 mg twice daily, or placebo at 2 study centers in the United States and Germany, or canagliflozin 30 mg once daily or placebo at 1 study center in Korea, while maintaining an isocaloric diet for 2 weeks. On Days -1, 1, and 16, urinary glucose excretion (UGE), plasma glucose (PG), fasting PG (FPG), and insulin were measured. The renal threshold for glucose (RTG) was calculated from UGE, PG, and estimated glomerular filtration rate. Safety was evaluated based on adverse event (AE) reports, vital signs, electrocardiograms, clinical laboratory tests, and physical examinations. RESULTS: Canagliflozin increased UGE dose-dependently (,80-120 g/day with canagliflozin $100 mg), with increases maintained over the 14-day dosing period with each dose. Canagliflozin dose-dependently decreased RTG, with maximal reductions to ,4-5 mM (72-90 mg/dL). Canagliflozin also reduced FPG and 24-hour mean PG; glucose reductions were seen on Day 1 and maintained over 2 weeks. Plasma insulin reductions with canagliflozin were consistent with observed PG reductions. Canagliflozin also reduced body weight. AEs were transient, mild to moderate in intensity, and balanced across groups; 1 canagliflozin-treated female reported an episode of vaginal candidiasis. Canagliflozin did not cause hypoglycemia, consistent with the RTG values remaining above the hypoglycemia threshold. At Day 16, there were no clinically meaningful changes in urine volume, urine electrolyte excretion, renal function, or routine laboratory test values. CONCLUSIONS: Canagliflozin increased UGE and decreased RTG, leading to reductions in PG, insulin, and body weight, and was generally well tolerated in patients with type 2 diabetes. TRIAL REGISTRATION: ClinicalTrials.gov NCT00963768.

Pharmacodynamic effects of canagliflozin, a sodium glucose co-transporter 2 inhibitor, from a randomized study in patients with type 2 diabetes.

INTRODUCTION: This randomized, double-blind, placebo-controlled, single and multiple ascending-dose study evaluated the pharmacodynamic effects and safety/tolerability of canagliflozin, a sodium glucose co-transporter 2 inhibitor, in patients with type 2 diabetes. METHODS: Patients (N = 116) discontinued their antihyperglycemic medications 2 weeks before randomization. Patients received canagliflozin 30, 100, 200, or 400 mg once daily or 300 mg twice daily, or placebo at 2 study centers in the United States and Germany, or canagliflozin 30 mg once daily or placebo at 1 study center in Korea, while maintaining an isocaloric diet for 2 weeks. On Days -1, 1, and 16, urinary glucose excretion (UGE), plasma glucose (PG), fasting PG (FPG), and insulin were measured. The renal threshold for glucose (RTG) was calculated from UGE, PG, and estimated glomerular filtration rate. Safety was evaluated based on adverse event (AE) reports, vital signs, electrocardiograms, clinical laboratory tests, and physical examinations. RESULTS: Canagliflozin increased UGE dose-dependently (∼80-120 g/day with canagliflozin ≥100 mg), with increases maintained over the 14-day dosing period with each dose. Canagliflozin dose-dependently decreased RTG, with maximal reductions to ∼4-5 mM (72-90 mg/dL). Canagliflozin also reduced FPG and 24-hour mean PG; glucose reductions were seen on Day 1 and maintained over 2 weeks. Plasma insulin reductions with canagliflozin were consistent with observed PG reductions. Canagliflozin also reduced body weight. AEs were transient, mild to moderate in intensity, and balanced across groups; 1 canagliflozin-treated female reported an episode of vaginal candidiasis. Canagliflozin did not cause hypoglycemia, consistent with the RTG values remaining above the hypoglycemia threshold. At Day 16, there were no clinically meaningful changes in urine volume, urine electrolyte excretion, renal function, or routine laboratory test values. CONCLUSIONS: Canagliflozin increased UGE and decreased RTG, leading to reductions in PG, insulin, and body weight, and was generally well tolerated in patients with type 2 diabetes. TRIAL REGISTRATION: ClinicalTrials.gov NCT00963768.

Pharmacokinetics and pharmacodynamics of canagliflozin, a sodium glucose co-transporter 2 inhibitor, in subjects with type 2 diabetes mellitus.

This study characterized single- and multiple-dose pharmacokinetics of canagliflozin and its O-glucuronide metabolites (M5 and M7) and pharmacodynamics (renal threshold for glucose [RTG ], urinary glucose excretion [UGE0-24h ], and 24-hour mean plasma glucose [MPG0-24h ]) of canagliflozin in subjects with type 2 diabetes. Thirty-six randomized subjects received canagliflozin 50, 100, or 300 mg/day or placebo for 7 days. On Days 1 and 7, area under the plasma concentration-time curve and maximum observed plasma concentration (Cmax ) for canagliflozin and its metabolites increased dose-dependently. Half-life and time at which Cmax was observed were dose-independent. Systemic molar M5 exposure was half that of canagliflozin; M7 exposure was similar to canagliflozin. Steady-state plasma canagliflozin concentrations were reached by Day 4 in all active treatment groups. Pharmacodynamic effects were dose- and exposure-dependent. All canagliflozin doses decreased RTG , increased UGE0-24h , and reduced MPG0-24h versus placebo on Days 1 and 7. On Day 7, placebo-subtracted least-squares mean decreases in MPG0-24h ranged from 42-57 mg/dL with canagliflozin treatment. Adverse events (AEs) were balanced between treatments; no treatment-related serious AEs, AE-related discontinuations, or clinically meaningful adverse changes in routine safety evaluations occurred. The observed pharmacokinetic/pharmacodynamic profile of canagliflozin in subjects with type 2 diabetes supports a once-daily dosing regimen.

Validation of a novel method for determining the renal threshold for glucose excretion in untreated and canagliflozin-treated subjects with type 2 diabetes mellitus.

CONTEXT: The stepwise hyperglycemic clamp procedure (SHCP) is the gold standard for measuring the renal threshold for glucose excretion (RT(G)), but its use is limited to small studies in specialized laboratories. OBJECTIVE: The objective of the study was to validate a new method for determining RT(G) using data obtained during a mixed-meal tolerance test (MMTT) in untreated and canagliflozin-treated subjects with type 2 diabetes mellitus (T2DM). DESIGN: This was an open-label study with 2 sequential parts. SETTING: The study was performed at a single center in Germany. PATIENTS: Twenty-eight subjects with T2DM were studied. INTERVENTIONS: No treatment intervention was given in part 1. In part 2, subjects were treated with canagliflozin 100 mg/d for 8 days. In each part, subjects underwent an MMTT and a 5-step SHCP on consecutive days. MAIN OUTCOME MEASURES: For both methods, RT(G) was estimated using measured blood glucose (BG) and urinary glucose excretion (UGE); estimated glomerular filtration rates were also used to determine RT(G) during the MMTT. The methods were compared using the concordance correlation coefficient and geometric mean ratios. RESULTS: In untreated and canagliflozin-treated subjects, the relationship between UGE rate and BG was well described by a threshold relationship. Good agreement was obtained between the MMTT-based and SHCP-derived RT(G) values. The concordance correlation coefficient (for all subjects) was 0.94; geometric mean ratios (90% confidence intervals) for RT(G) values (MMTT/SHCP) were 0.93 (0.89-0.96) in untreated subjects and 1.03 (0.78-1.37) in canagliflozin-treated subjects. Study procedures and treatments were generally well tolerated in untreated and canagliflozin-treated subjects. CONCLUSIONS: In both untreated and canagliflozin-treated subjects with T2DM, RT(G) can be accurately estimated from measured BG, UGE, and estimated glomerular filtration rates using an MMTT-based method.

Usability of telepresence in a level 1 trauma center.

OBJECTIVES: Limited resources and the diminishing physician workforce in trauma require unique and innovative solutions. Our hypothesis is that telepresence by a remote physician is an appropriate application in an urban trauma setting. The purpose of this study is to assess user satisfaction and usability of a mobile telemedicine robot in trauma care. MATERIALS AND METHODS: A usability study of trauma patient assessments utilizing the Remote Presence-7 (RP-7) robot (InTouch Health, Santa Barbara, CA) with real-time, two-way communication between remote and local physicians was conducted at a Level 1 trauma center. Usability and acceptability was measured using survey questionnaires, open-ended feedback, and general observations. Comparisons were made between remote and local physician responses. RESULTS: One hundred fourteen patient encounters utilizing telepresence were performed. Remote and local physicians expressed a high level of satisfaction with the mobility (92% and 79%, respectively), communication (97% and 90%, respectively), and visual abilities (91% and 97%, respectively) of the RP-7 robot for remote consultation purposes. On average, 89% of remote and local physician participants rated their overall telemedicine experience as "excellent" or "above average." CONCLUSIONS: This study suggests that telepresence of a remote trauma surgeon may be a useful and functional adjunct in the trauma setting. Further development of these technologies could mitigate current and future concerns about gaps in rural and urban trauma care and critical care staffing shortages and during mass casualty or disaster scenarios.

Canagliflozin lowers postprandial glucose and insulin by delaying intestinal glucose absorption in addition to increasing urinary glucose excretion: results of a randomized, placebo-controlled study.

OBJECTIVE: Canagliflozin, a sodium glucose cotransporter (SGLT) 2 inhibitor, is also a low-potency SGLT1 inhibitor. This study tested the hypothesis that intestinal canagliflozin levels postdose are sufficiently high to transiently inhibit intestinal SGLT1, thereby delaying intestinal glucose absorption. RESEARCH DESIGN AND METHODS: This two-period, crossover study evaluated effects of canagliflozin on intestinal glucose absorption in 20 healthy subjects using a dual-tracer method. Placebo or canagliflozin 300 mg was given 20 min before a 600-kcal mixed-meal tolerance test. Plasma glucose, (3)H-glucose, (14)C-glucose, and insulin were measured frequently for 6 h to calculate rates of appearance of oral glucose (RaO) in plasma, endogenous glucose production, and glucose disposal. RESULTS: Compared with placebo, canagliflozin treatment reduced postprandial plasma glucose and insulin excursions (incremental 0- to 2-h area under the curve [AUC0-2h] reductions of 35% and 43%, respectively; P < 0.001 for both), increased 0- to 6-h urinary glucose excretion (UGE0-6h, 18.2 ± 5.6 vs. <0.2 g; P < 0.001), and delayed RaO. Canagliflozin reduced AUC RaO by 31% over 0 to 1 h (geometric means, 264 vs. 381 mg/kg; P < 0.001) and by 20% over 0 to 2 h (576 vs. 723 mg/kg; P = 0.002). Over 2 to 6 h, canagliflozin increased RaO such that total AUC RaO over 0 to 6 h was <6% lower versus placebo (960 vs. 1,018 mg/kg; P = 0.003). A modest (∼10%) reduction in acetaminophen absorption was observed over the first 2 h, but this difference was not sufficient to explain the reduction in RaO. Total glucose disposal over 0 to 6 h was similar across groups. CONCLUSIONS: Canagliflozin reduces postprandial plasma glucose and insulin by increasing UGE (via renal SGLT2 inhibition) and delaying RaO, likely due to intestinal SGLT1 inhibition.

Quantifying monocyte infiltration in response to intradermal tetanus toxoid injection.

AIMS: To characterize monocyte response in a delayed-type hypersensitivity reaction to intradermal tetanus toxoid (TT) injection. MATERIALS & METHODS: Men with positive serum anti-tetanus titers were stratified by last TT vaccination. Subjects were administered three intradermal injections of TT and one saline control on the same side of the back. Skin biopsies were taken post-injection. After 2 weeks, the procedure was repeated on the contralateral side. RESULTS: Men who received TT booster vaccination 1 month before the study showed greater reproducibility and lower variability in monocyte responses than those who were not revaccinated. Monocyte concentration in subjects re-vaccinated within 1 month of study start appeared maximal at 48 h post-injection. CONCLUSION: This assay represents a novel approach that allows for quantification of dermal monocyte/macrophage influx. This clinical methodology has potential utility in the pharmacodynamic evaluation of therapies targeting inflammatory disorders, which involve monocyte tissue recruitment, like the delayed-type hypersensitivity response.