Circadian and sex differences in carotid-femoral pulse wave velocity in young individuals and elderly with and without type 2 diabetes

Postexercise cardiovascular hemodynamics assessment before and after a 30-minute standing still recovery

BACKGROUND

Although postexercise syncope usually occurs shortly after physical exercise conclusion, athletes commonly reveal symptoms of postexercise hypotension several tens of minutes after exercise completion. Currently, no studies have investigated central hemodynamic regulation during posture changes occurring several tens of minutes after exercise compared to immediately after cessation.

METHODS

This study examined changes in mean arterial pressure (MAP), heart rate (HR), systemic vascular conductance (SVC), cardiac output, and stroke volume during two sets of tilt tests performed before vs. after a 30-minute standing still recovery, respectively. Tilt tests were performed after a short-lasting supramaximal test (WNG) and long-lasting maximal incremental test (INC) in 12 young endurance-trained individuals.

RESULTS

The key findings were that, regardless of the exercise type, the 30-minute recovery augmented (P<0.01) the increase in HR and the drop in SVC during the transition from supine to upright, although the MAP drop was similar (P=0.99) after vs. before recovery. INC led to greater increases (P<0.01) in HR and drops (P<0.01) in SVC compared to WNG during postural transitions both before and after the recovery.

CONCLUSIONS

These findings suggest that, in a population that tolerates postexercise hypotension, MAP neural control is more challenged after a 30-minute standing still recovery than before, as evidenced by an augmented vasodilation capacity along with an increased HR buffering response during posture changes. Moreover, our data suggest that effective MAP control is resulting from an equally effective HR buffering response on MAP. Therefore, exercises that induce greater systemic vasodilation lead to greater HR buffering responses.

Circadian and sex differences in post-ischemic vasodilation and reactive hyperemia in young individuals and elderly with and without type 2 diabetes

OBJECTIVE

Cardiovascular events show morning preference and sex differences, and are related to aging and type 2 diabetes. We assessed circadian variations and sex differences in vascular conductance (VC) and blood flow (BF) regulations following a brief bout of forearm ischemia.

METHODS

Young healthy individuals (H18-30) and elderly without (H50-80) and with type 2 diabetes (T2DM50-80) of both sexes were included. Forearm VC and BF, and mean arterial pressure (MAP) at baseline and following circulatory reperfusion were measured at 6 a.m. and 9 p.m.

RESULTS

In the morning compared to evening, following reperfusion, the VC and BF increments were similar in H18-30 (p>.71), but lower in H50-80 (p<.001) and T2DM50-80 (p<.01). VC and BF following circulatory reperfusion were higher in men than women in H18-30 (p<.001), but similar between sexes in the older groups (p>.23).

CONCLUSIONS

Forearm vasodilation following reperfusion is attenuated in the morning in the elderly, impairing BF towards an ischemic area. Diabetes does not affect the circadian regulation of VC and BF, but that of MAP. There are sex differences in VC and BF at baseline and after circulatory reperfusion at a young age, being greater in men, which disappear with aging without being affected by diabetes.

Cardiovascular prevention in women: an update by the Italian Society of Cardiology working group on 'Prevention, hypertension and peripheral disease'

The recent pandemic has substantially changed the approach to the prevention of cardiovascular diseases in women. Women have been significantly impacted by the changes that occurred during the pandemic and the quarantine adopted to prevent the spread of the disease. Changes involved prevention both through the reduction of visits and preventive screening and through social and economic changes. It is necessary to adopt new cardiovascular prevention approaches focused on returning to healthy lifestyles, reducing stress and depression also using modern tools such as telemedicine, mobile phone applications and the web. These tools convey messages in a persuasive way especially in young and adult women. There is less impact of these new tools on older women towards whom it is important to adopt a more traditional approach. This review focuses on the new approach to cardiovascular prevention in women in light of the lifestyle changes recorded during the pandemic and which led to an increase in obesity examines the effects on the cardiovascular system induced by stress and depression and analyses the new high blood pressure guidelines and indications that are specific to women.

Estimated pulse wave velocity is associated with all-cause mortality and cardiovascular mortality among adults with diabetes

Aims

We aim to examine the association of estimated pulse wave velocity (ePWV) with all-cause and cardiovascular mortality in patients with diabetes.

Methods

All of adult participants with diabetes from the National Health and Nutrition Examination Survey (NHANES) (1999-2018) were enrolled. ePWV was calculated according to the previously published equation based on age and mean blood pressure. The mortality information was obtained from the National Death Index database. Weighted Kaplan-Meier (KM) plot and weighted multivariable Cox regression was used to investigate the association of ePWV with all-cause and cardiovascular mortality risks. Restricted cubic spline was adopted to visualize the relationship between ePWV and mortality risks.

Results

8,916 participants with diabetes were included in this study and the median follow-up duration was ten years. The mean age of study population was 59.0 ± 11.6 years, 51.3% of the participants were male, representing 27.4 million patients with diabetes in weighted analysis. The increment of ePWV was closely associated with increased risks of all-cause mortality (HR: 1.46, 95% CI: 1.42-1.51) and cardiovascular mortality (HR: 1.59, 95% CI: 1.50-1.68). After adjusting for cofounding factors, for every 1 m/s increase in ePWV, there was a 43% increased risk of all-cause mortality (HR: 1.43, 95% CI: 1.38-1.47) and 58% increased of cardiovascular mortality (HR: 1.58, 95% CI: 1.50-1.68). ePWV had positive linear associations with all-cause and cardiovascular mortality. KM plots also showed that the risks of all-cause and cardiovascular mortality were significantly elevated in patients with higher ePWV.

Conclusions

ePWV had a close association with all-cause and cardiovascular mortality risks in patients with diabetes.

Circadian Variations in Sympathetic Vasoconstriction in Older Adults with and Without Type 2 Diabetes

INTRODUCTION

An impact of the sympathetic nervous system in the higher rate of cardiovascular events in the early morning compared to the evening has been claimed. Augmented sympathetic vasoconstriction increases cardiovascular risk by augmenting pulse pressure and cardiac afterload. Type 2 diabetes (T2DM) further increases sympathetic neurovascular transduction and cardiovascular risk.

AIM

We assessed whether peripheral vasoconstriction triggered by a standardized sympathetic stressor is augmented at 6am vs 9pm in adults between 50-80 years with type 2 diabetes (T2DM50-80) vs healthy ones (H50-80).

METHODS

Mean values of sympathetic vasoconstrictor responsiveness (SVR), vascular conductance (VC), brachial artery blood flow, and mean arterial pressure were measured on the contralateral forearm over two 5-minute bouts of rest and handgrip-mediated sympathetic stimulation, respectively.

RESULTS

Although baseline VC values were lower (p < 0.01) in the morning vs evening in both groups, SVR values in response to sympathoexcitation were similar in H50-80 (- 0.43 ± 12.44 vs - 2.57 ± 11.63 %, p = 0.73) and T2DM50-80 (+6.64 ± 10.67 vs +5.21 ± 7.64 %, p = 0.90), but higher (p < 0.01) in T2DM50-80 vs H50-80 at both day hours. Individuals with T2DM reported positive SVR values and VC change-scores, while healthy individuals reported statistically different (p < 0.02) negative SVR values and VC change-scores.

CONCLUSION

Peripheral vasoconstriction triggered by a standardized sympathetic stressor is similar between morning and evening, regardless of T2DM and different baseline VC values. However, peripheral vasoconstriction responsiveness is blunted in individuals with T2DM as handgrip-mediated sympathoexcitation induces vasodilation in the contralateral forearm in adults with T2DM and vasoconstriction in healthy age-matched controls, highlighting a neurovascular response altered by T2DM.