Metabolic syndrome and arterial stiffness: evidence for gender disparity and early effects of non-traditional risk factors?

Dapagliflozin decreases ambulatory central blood pressure and pulse wave velocity in patients with type 2 diabetes: a randomized, double-blind, placebo-controlled clinical trial

OBJECTIVES

Sodium-glucose co-transporter 2 (SGLT-2) inhibitors reduce the incidence of heart failure and death in patients with type-2 diabetes mellitus. Arterial stiffness is a prominent risk factor for heart failure and overall mortality. The aim of this study was to evaluate the effects of dapagliflozin on ambulatory brachial and central blood pressure (BP) levels and arterial stiffness parameters in patients with type-2 diabetes mellitus.

METHODS

This is a double-blind, randomized, placebo-controlled clinical trial including 85 adult patients with type-2 diabetes mellitus on monotherapy or combination therapy with two of: metformin, sulphonylurea, DPP-4 inhibitor, or insulin. Patients were randomized in a 1 : 1 ratio to oral dapagliflozin 10 mg per day or placebo for 12 weeks. Study participants underwent 24-h ambulatory BP monitoring with the Mobil-O-Graph NG monitor at baseline and study-end.

RESULTS

Baseline demographic, clinical and laboratory parameters were similar in the two groups. During follow-up, 24-h brachial SBP/DBP (129.0 ± 12.6/77.3 ± 7.3 vs. 123.2 ± 12.4/75.1 ± 6.4 mmHg; P < 0.001/P = 0.008) and central SBP/DBP (117.4 ± 10.5/78.9 ± 7.3 vs. 113.3 ± 8.8/77.3 ± 6.5 mmHg; P = 0.002/P = 0.047) significantly decreased in dapagliflozin but not in the placebo group. Corresponding reductions of 24-h brachial SBP (-5.8 ± 9.5 vs. -0.1 ± 8.7, P = 0.005) and central SBP (-4.1 ± 8.0 vs. -0.7 ± 7.8; P = 0.046) were greater with dapagliflozin than placebo. Twenty-four-hour heart-rate adjusted augmentation index significantly decreased with dapagliflozin and insignificantly with placebo. Importantly, there was a significant difference in change of estimated 24-h PWV (-0.16 ± 0.32 vs. 0.02 ± 0.27; P = 0.007) favoring dapagliflozin. In generalized linear mixed models including 24-h brachial SBP as a random covariate, the adjusted marginal means of delta 24-h central SBP and delta 24-h PWV were not significantly different between-groups.

CONCLUSION

Treatment with dapagliflozin significantly reduces ambulatory brachial and central BP levels and PWV in patients with type-2 diabetes mellitus. Improvement in these parameters may substantially contribute to the cardiovascular benefits of SGLT-2 inhibitors.

Comparison of ambulatory central hemodynamics and arterial stiffness in patients with diabetic and non-diabetic CKD

Increased arterial stiffness is independently associated with renal function decline in patients with diabetes mellitus (DM). Whether DM has additional deleterious effects on central hemodynamics and arterial stiffness in chronic kidney disease (CKD) patients is yet unknown. This study aimed to compare ambulatory central BP, arterial stiffness parameters, and trajectories between patients with diabetic and non‐diabetic CKD. This study examined 48 diabetic and 48 non‐diabetic adult patients (>18 years) with CKD (eGFR: <90 and ≥15 ml/min/1.73 m²), matched in a 1:1 ratio for age, sex, and eGFR within CKD stages (2, 3a, 3b and 4). All patients underwent 24‐h ABPM with the Mobil‐O‐Graph device. Parameters of central hemodynamics [central systolic (cSBP) and diastolic blood pressure (cDBP), pulse pressure (PP)], wave reflection [augmentation index (AIx), and pressure (AP)] and pulse wave velocity (PWV) were estimated from the 24‐h recordings. Diabetic CKD patients had higher 24‐h cSBP (118.57 ± 10.05 vs. 111.59 ± 9.46, P = .001) and 24‐h cPP (41.48 ± 6.80 vs. 35.25 ± 6.98, P < .001) but similar 24‐h cDBP (77.09 ± 8.14 vs. 76.34 ± 6.75 mmHg, P = .625) levels compared to patients with non‐diabetic CKD. During day‐ and nighttime periods, cSBP and cPP levels were higher in diabetics compared to non‐diabetics. 24‐h PWV (10.10 ± 1.62 vs. 9.61 ± 1.80 m/s, P = .165) was numerically higher in patients with DM, but no between‐group differences were noted in augmentation pressure and index. In multivariate analysis, DM, female gender, and peripheral SBP were independently associated with higher cPP levels. Patients with diabetic CKD have higher ambulatory cSBP and increased arterial stiffness, as indicated by higher ambulatory cPP. These finding suggest that DM is a factor independently contributing to the adverse macrocirculatory profile of CKD patients.

Treatment of hypertension in obese patients

Obesity is a global pandemic and with its rise, its associated co-morbidities are increasing in prevalence, particularly uncontrolled hypertension. Lifestyle changes should be an anchor for the management of obesity-related hypertension; however, they are difficult to sustain. Drug therapy is often necessary to achieve blood pressure control. Diuretics, inhibitors of the renin-angiotensin system, and dihydropyridine calcium channel blockers are often used as first trio, with subsequent additions of mineralocorticoid receptor antagonists and/or dual alpha/beta blocking agents. While a number of agents are currently available, 50 % of hypertensive patients remain uncontrolled. A number of novel drug and invasive therapies are in development and hold significant potential for the effective management of obesity-related hypertension.

Gender differences in the prevalence of metabolic syndrome and its components among adults with disabilities based on a community health check up data

Metabolic syndrome is highly prevalent in society gradually and has important implications for public health in recent years. The present study aims to examine the gender effect on the prevalence of metabolic syndrome among adults with disabilities. A cross-sectional study was conduct to analyze annual health check-up chart of 419 people with disabilities whose age ≥ 20 years in east Taiwan. We used to diagnose the metabolic syndrome was defined by the Taiwan Bureau of Health Promotion as the presence of three or more of the following five components: abdominal obesity, high blood pressure, high fasting glucose level, high triglyceride level, and low high-density lipoprotein cholesterol level. The results showed that the prevalence of metabolic syndrome was 19.3% in the study subjects (16.8% in men and 23.1% in women; p = 0.110). Our study also indicated that the genders were significantly different in the followings (men vs. women): abdominal obesity (33.2% vs. 50.9%; p<0.001), high blood pressure (36.4% vs. 23.7%; p = 0.006), high fasting glucose level (18.4 vs. 14.8%; p = 0.334), high triglyceride level (24.0% vs. 14.2%; p = 0.014) and HDL-C (21.6% vs. 35.5%; p = 0.002) among the sample. To prevent the metabolic syndrome occurrence and consequences, the study suggests that the health authorities should put greater efforts to address the metabolic syndrome components, particularly in higher rates of obesity-related health conditions to avoid significant health and health care costs in the future.

PPAR-γ agonism for cardiovascular and renal protection

Diabetes mellitus is an established risk factor for cardiovascular disease and the leading cause of end-stage renal disease in the Western World. Thiazolidinediones (TZDs) represent a class of antidiabetic agents that exert their glucose-lowering effects by reducing insulin resistance, through stimulation of a type of nuclear receptor, called peroxisome proliferator-activated receptor-γ. Apart from improving glycemic control, TZDs were shown to exert beneficial effects on several components of the metabolic syndrome and cardiovascular risk markers. Furthermore, background and human studies have shown that TZDs reduce urinary albumin and protein excretion and interfere with most of the pathogenentic pathways involved in the development and progression of diabetic nephropathy. On the other hand, currently used TZDs have side effects, most important of which is fluid retention leading to wait gain and heart failure deterioration. With regards to cardiovascular outcomes, the anticipated benefit of TZDs was demonstrated for pioglitazone, whereas a series of previous meta-analyses linking rosiglitazone treatment with increased risk of myocardial infarction and cardiovascular death raised uncertainty around the cardiovascular safety of rosiglitazone. This article will discuss the effects of TZDs on established and emerging cardiovascular risk factors, the data on possible beneficial renal effects of these compounds, and the existing evidence from large-scale clinical trials and meta-analyses on their effects on cardiovascular outcomes, aiming to provide an overview of the cardio- and renoprotective properties of these drugs.

Secondary hypertension: obesity and the metabolic syndrome

The epidemic of obesity in the United States and around the world is intensifying in severity and scope and has been implicated as an underlying mechanism in systemic hypertension. Obese hypertensive individuals characteristically exhibit volume congestion, relative elevation in heart rate, and high cardiac output with concomitant activation of the renin-angiotensin-aldosterone system. When the metabolic syndrome is present, insulin resistance and hyperinsulinemia may contribute to hypertension through diverse mechanisms. Blood pressure can be lowered when weight control measures are successful, using, for example, caloric restriction, aerobic exercise, weight loss drugs, or bariatric surgery. A major clinical challenge resides in converting short-term weight reduction into a sustained benefit. Pharmacotherapy for the obese hypertensive patient may require multiple agents, with an optimal regimen consisting of inhibitors of the renin-angiotensin-aldosterone system, thiazide diuretics, beta-blockers, and calcium channel blockers if needed to attain contemporary blood pressure treatment goals.

Insulin Resistance and Oxidant Stress: An Interrelation With Deleterious Renal Consequences?

Within the past years, several epidemiologic studies have shown that insulin resistance and hyperinsulinemia are associated with chronic kidney disease, and experimental data suggest that a number of background mechanisms could connect insulin resistance with renal injury. Moreover, the acute sodium-retaining action of insulin at the kidney level has been proposed to participate in the development of salt sensitivity in essential hypertension. Current knowledge suggests that oxidative stress can be involved in the development of renal injury and can also promote primary salt retention at the kidney level. Insulin resistance and hyperinsulinemia seem to be closely connected with oxidative stress in the form of a vicious circle. This article discusses the potential role of oxidative stress as a mediator of the renal effects of insulin resistance/hyperinsulinemia.