Low body mass index is a risk factor forimpaired endothelium-dependent vasodilation in humans: role of nitric oxide and oxidative stress

AbstractObjectivesThe purpose of this study was to evaluate the relationship between body mass index (BMI), including low BMIs, and endothelial function.BackgroundEpidemiologic study has demonstrated that not only obesity but also a low BMI may be a risk factor for cardiovascular disease.MethodsThe forearm blood flow (FBF) response to acetylcholine (ACh) and isosorbide dinitrate (ISDN) was measured in 87 healthy young men (15 low BMI, 51 normal, 14 obese, and 7 extremely obese).ResultsPlasma concentrations of 8-hydroxy-2′-deoxyguanosine and serum concentrations of malondialdehyde-modified low-density lipoprotein were higher in low BMI, obese, and extremely obese subjects than in normal subjects and were similar among the low BMI, obese, and extremely obese groups. The FBF response to ACh was greater in the normal group than in the other groups (p < 0.001), and was lower in the extremely obese group as compared with the other groups (p < 0.001). The ACh-stimulated vasodilation was similar between the low BMI group and the obese group. The ISDN-stimulated vasodilation was similar in all four groups. There were no significant differences in ACh-stimulated vasodilation between the four groups after the nitric oxide (NO) synthase inhibitor NG-monomethyl-L-arginine infusion. Co-infusion of vitamin C augmented the FBF response to ACh in low BMI, obese, and extremely obese groups—but not in normal BMI group.ConclusionsThese findings suggest that not only obesity but also a low BMI may be a risk factor for impaired endothelium-dependent vasodilation through the increased oxidative stress, leading to the reduced bioavailability of NO

Effect of Saxagliptin on Endothelial Function in Patients with Type 2 Diabetes : A Prospective Multicenter Study

The dipeptidyl peptidase-4 inhibitor saxagliptin is a widely used antihyperglycemic agent in patients with type 2 diabetes. The purpose of this study was to evaluate the effects of saxagliptin on endothelial function in patients with type 2 diabetes. This was a prospective, multicenter, interventional study. A total of 34 patients with type 2 diabetes were enrolled at four university hospitals in Japan. Treatment of patients was initially started with saxagliptin at a dose of 5 mg daily. Assessment of endothelial function assessed by flow-mediated vasodilation (FMD) and measurement of stromal cell-derived factor-1α (SDF-1α) were conducted at baseline and at 3 months after treatment with saxagliptin. A total of 31 patients with type 2 diabetes were included in the analysis. Saxagliptin significantly increased FMD from 3.1 ± 3.1% to 4.2 ± 2.4% (P = 0.032) and significantly decreased total cholesterol from 190 ± 24 mg/dL to 181 ± 25 mg/dL (P = 0.002), glucose from 160 ± 53 mg/dL to 133 ± 25 mg/dL (P < 0.001), HbA1c from 7.5 ± 0.6% to 7.0 ± 0.6% (P < 0.001), urine albumin-to-creatinine ratio from 63.8 ± 134.2 mg/g to 40.9 ± 83.0 mg/g (P = 0.043), and total SDF-1α from 2108 ± 243 pg/mL to 1284 ± 345 pg/mL (P < 0.001). These findings suggest that saxagliptin is effective for improving endothelial function

発症早期ALS患者に対する超高用量メチルコバラミンの有効性・安全性について : ランダム化比較試験

Importance: Post hoc analysis in a phase 2/3 trial indicated ultra-high dose methylcobalamin slowed decline of the Revised Amyotrophic Lateral Sclerosis Functional Rating Scale (ALSFRS-R) total score at week 16 as well as at week 182, without increase of adverse events, in patients with amyotrophic lateral sclerosis (ALS) who were enrolled within 1 year from onset. Objective: To validate the efficacy and safety of ultra-high dose methylcobalamin for patients with ALS enrolled within 1 year of onset. Design: A multicenter, placebo-controlled, double-blind, randomized phase 3 trial with 12-week observation and 16-week randomized period, conducted from October 2017 to September 2019. Setting: Twenty-five neurology centers in Japan. Participants: Patients with ALS diagnosed within 1 year of onset by the updated Awaji criteria were initially enrolled. Of those, patients fulfilling the following criteria after 12-week observation were eligible for randomization: 1- or 2-point decrease in ALSFRS-R total score, a percent forced vital capacity over 60%, no history of noninvasive respiratory support and tracheostomy, and being ambulant. The target number was 64 in both methylcobalamin and placebo groups. Of 203 patients enrolled in the observation, 130 patients (age, 61.0 ± 11.7 years; female, 56) met the criteria and were randomly assigned through an electronic web-response system to methylcobalamin or placebo (65 for each). Of these, 129 patients were eligible for the full analysis set, and 126 completed the double-blind stage. Interventions: Intramuscular injection of methylcobalamin 50 mg or placebo twice weekly for 16 weeks. Main outcomes and measures: The primary endpoint was change in ALSFRS-R total score from baseline to week 16 in the full analysis set. Results: The least-squares mean difference in ALSFRS-R total score at week 16 of the randomized period was 1.97 points greater with methylcobalamin than placebo (−2.66 versus −4.63; 95% CI, 0.44–3.50; P = 0.012). The incidence of adverse events was similar between the two groups. Conclusions and relevance: Ultra-high dose methylcobalamin was efficacious in slowing functional decline and safe in the 16-week treatment period in ALS patients in the early stage and with moderate progression rate. Trial registration: UMIN-CTR Identifier: UMIN000029588 (umin.ac.jp/ctr); ClinicalTrials.gov Identifier: NCT03548311 (clinicaltrials.gov

Endothelial Dysfunction, Increased Arterial Stiffness, and Cardiovascular Risk Prediction in Patients With Coronary Artery Disease: FMD‐J (Flow‐Mediated Dilation Japan) Study A

BackgroundThe usefulness of vascular function tests for management of patients with a history of coronary artery disease is not fully known.Methods and ResultsWe measured flow‐mediated vasodilation (FMD) and brachial–ankle pulse wave velocity (baPWV) in 462 patients with coronary artery disease for assessment of the predictive value of FMD and baPWV for future cardiovascular events in a prospective multicenter observational study. The first primary outcome was coronary events, and the second primary outcome was a composite of coronary events, stroke, heart failure, and sudden death. During a median follow‐up period of 49.2 months, the first primary outcome occurred in 56 patients and the second primary outcome occurred in 66 patients. FMD above the cutoff value of 7.1%, derived from receiver‐operator curve analyses for the first and second primary outcomes, was significantly associated with lower risk of the first (hazard ratio, 0.27; 95% confidence interval, 0.06–0.74; P=0.008) and second (hazard ratio, 0.32; 95% confidence interval, 0.09–0.79; P=0.01) primary outcomes. baPWV above the cutoff value of 1731 cm/s was significantly associated with higher risk of the first (hazard ratio, 1.86; 95% confidence interval, 1.01–3.44; P=0.04) and second (hazard ratio, 2.19; 95% confidence interval, 1.23–3.90; P=0.008) primary outcomes. Among 4 groups stratified according to the combination of cutoff values of FMD and baPWV, stepwise increases in the calculated risk ratio for the first and second primary outcomes were observed.ConclusionsIn patients with coronary artery disease, both FMD and baPWV were significant predictors of cardiovascular events. The combination of FMD and baPWV provided further cardiovascular risk stratification

FMD, PWV, and Cardiovascular Events

Background The usefulness of vascular function tests for management of patients with a history of coronary artery disease is not fully known. Methods and Results We measured flow‐mediated vasodilation (FMD) and brachial–ankle pulse wave velocity (baPWV) in 462 patients with coronary artery disease for assessment of the predictive value of FMD and baPWV for future cardiovascular events in a prospective multicenter observational study. The first primary outcome was coronary events, and the second primary outcome was a composite of coronary events, stroke, heart failure, and sudden death. During a median follow‐up period of 49.2 months, the first primary outcome occurred in 56 patients and the second primary outcome occurred in 66 patients. FMD above the cutoff value of 7.1%, derived from receiver‐operator curve analyses for the first and second primary outcomes, was significantly associated with lower risk of the first (hazard ratio, 0.27; 95% confidence interval, 0.06–0.74; P=0.008) and second (hazard ratio, 0.32; 95% confidence interval, 0.09–0.79; P=0.01) primary outcomes. baPWV above the cutoff value of 1731 cm/s was significantly associated with higher risk of the first (hazard ratio, 1.86; 95% confidence interval, 1.01–3.44; P=0.04) and second (hazard ratio, 2.19; 95% confidence interval, 1.23–3.90; P=0.008) primary outcomes. Among 4 groups stratified according to the combination of cutoff values of FMD and baPWV, stepwise increases in the calculated risk ratio for the first and second primary outcomes were observed. Conclusions In patients with coronary artery disease, both FMD and baPWV were significant predictors of cardiovascular events. The combination of FMD and baPWV provided further cardiovascular risk stratification