Pulse pressure and cardiovascular autonomic neuropathy according to duration of type 1 diabetes

Central blood pressure estimation in type 1 diabetes: impact and implications of peripheral calibration method

OBJECTIVE

Peripheral blood pressure (BP) waveforms are used for noninvasive central BP estimation. Central BP could assist in cardiovascular risk assessment in patients with type 1 diabetes mellitus (T1DM). However, correct calibration of peripheral BP waveforms is important to accurately estimate central BP. We examined differences in central BP estimated by radial artery tonometry depending on which brachial BP (SBP/DBP vs. MAP/DBP) is used for calibration of the radial waveforms, for the first time in T1DM.

METHODS

A cross-sectional study in T1DM patients without known cardiovascular disease. Radial artery BP waveforms were acquired using applanation tonometry ( SphygmoCor ) for the estimation of central SBP, central pulse pressure (PP) and central augmentation pressure, using either brachial SBP/DBP or MAP/DBP for the calibration of the radial pressure waveforms.

RESULTS

Fifty-four patients (age: 46 ± 9.5 years; T1DM duration: 27 ± 8.8 years) were evaluated. Central BP parameters were significantly higher when brachial MAP/DBP-calibration was used compared with brachial SBP/DBP-calibration (7.5 ± 5.04, 7.5 ± 5.04 and 1.5 ± 1.36 mmHg higher central SBP, central PP and central augmentation pressure, respectively, P  < 0.001).

CONCLUSION

In patients with T1DM, there are significant differences in central BP values estimated with radial artery tonometry, depending on the method used for calibration of the radial waveforms. Brachial MAP/DBP-calibration resulted in consistently higher central BP as compared to using brachial SBP/DBP, leading to patient re-stratification. Hence, the accuracy of noninvasive estimation of central BP by radial tonometry is dependent on calibration approach, and this problem must be resolved in validation studies using an invasive reference standard to determine which method best estimates true central BP.

Ginsenoside Rb1 Ameliorates Diabetic Arterial Stiffening via AMPK Pathway

Background and Purpose: Macrovascular complication of diabetes mellitus, characterized by increased aortic stiffness, is a major cause leading to many adverse clinical outcomes. It has been reported that ginsenoside Rb1 (Rb1) can improve glucose tolerance, enhance insulin activity, and restore the impaired endothelial functions in animal models. The aim of this study was to explore whether Rb1 could alleviate the pathophysiological process of arterial stiffening in diabetes and its potential mechanisms. Experimental Approach: Diabetes was induced in male C57BL/6 mice by administration of streptozotocin. These mice were randomly selected for treatment with Rb1 (10-60 mg/kg, i. p.) once daily for 8 weeks. Aortic stiffness was assessed using ultrasound and measurement of blood pressure and relaxant responses in the aortic rings. Mechanisms of Rb1 treatment were studied in MOVAS-1 VSMCs cultured in a high-glucose medium. Key Results: Rb1 improved DM-induced arterial stiffening and the impaired aortic compliance and endothelium-dependent vasodilation. Rb1 ameliorated DM-induced aortic remodeling characterized by collagen deposition and elastic fibers disorder. MMP2, MMP9, and TGFβ1/Smad2/3 pathways were involved in this process. In addition, Rb1-mediated improvement of arterial stiffness was partly achieved via inhibiting oxidative stress in DM mice, involving regulating NADPH oxidase. Finally, Rb1 could blunt the inhibition effects of DM on AMPK phosphorylation. Conclusion and Implications: Rb1 may represent a novel prevention strategy to alleviate collagen deposition and degradation to prevent diabetic macroangiopathy and diabetes-related complications.

A randomized comparison between pulse pressure variation and central venous pressure in patients undergoing renal transplantation

Background and Aims:

Intraoperative fluid management is important in renal transplant recipients with end-stage renal disease. Conventionally, central venous pressure (CVP) has been used to guide perioperative fluid administration but with high incidence of poor graft outcome. There is a requirement of reliable parameter to guide the fluid therapy in these patients so as to minimize the perioperative complications and improve the outcome. Hence, this study was conducted.

Material and Methods:

This prospective study included 75 patients of chronic kidney disease undergoing renal transplantation. Patients were divided into two groups. Group A (control group): Intraoperative fluids were guided by CVP; Group B: Intraoperative fluids were guided by pulse pressure variation (PPV). Primary outcome measure of this study was incidence of delayed graft functioning, i.e., need of hemodialysis within 7 days of renal transplant. Secondary outcome measures were incidence of perioperative hypotension, post-transplant pulmonary edema, tissue edema, and lactic acidosis.

Results:

Total amount of fluid before reperfusion was significantly greater in the control group (P = 0.005). However, the total amount of fluid required at the end of surgery was comparable. Delayed graft functioning was seen only in CVP group, although it was not statistically significant. The postoperative tissue edema was more in CVP group (P = 0.03). The postoperative nausea and vomiting, pulmonary edema, and mechanical ventilation were more in CVP group but not statistically significant. Increase in lactate value was more in CVP group.

Conclusion:

Perioperative fluid guidance by PPV is better than central venous pressure in renal transplant patients.

Early changes of arterial elasticity in Type 1 diabetes with microvascular complications - A cross-sectional study from childhood to adulthood

AIM

To examine the trajectory of small artery elasticity (SAE) and pulse pressure (PP) in people with Type 1 diabetes and non-diabetic controls across the lifespan, and explore associations with microvascular complications (CX+).

METHODS

This cross-sectional study included 477 Type 1 diabetes patients (188 with CX+, 289 without CX-) and 515 controls. Relationships between SAE and PP and age were evaluated using segmented linear regression. Logistic regression was used to assess the associations between microvascular complications (retinopathy and/or nephropathy) and SAE and PP.

RESULTS

SAE peaked significantly later among controls than diabetic patients CX- vs. CX+ (21.2 vs. 20.4 vs. 17.6 years respectively, p < 0.001). In adults, mean SAE was significantly lower in CX+ vs. CX- vs. controls (6.8 vs. 7.8 vs. 8.0 ml/mm Hg × 10; p < 0.0001), and mean PP was significantly higher in CX+ vs CX- and controls (60 vs. 55 vs. 53 mm Hg; p < 0.0001).

CONCLUSION

Type 1 diabetes CX+ subjects have an earlier peak and decline in SAE relative to CX- and controls, who did not differ. Lower SAE and higher PP were associated with increased odds of Type 1 diabetes complications in adults. These clinically applicable techniques demonstrate an association between accelerated vascular aging and vascular complications in diabetes.

Cardiovascular Autonomic Neuropathy Is an Independent Risk Factor for Left Ventricular Diastolic Dysfunction in Patients with Type 2 Diabetes

Aim

This study aimed to evaluate the association between cardiovascular autonomic neuropathy (CAN) and left ventricular diastolic dysfunction (LVDD) in type 2 diabetes patients.

Methods

315 type 2 diabetes patients from inpatients of Drum Tower Hospital were included and classified into no CAN (NCAN), possible CAN (PCAN), and definite CAN (DCAN) based on cardiovascular autonomic reflex tests. The left ventricular diastolic function was assessed by tissue Doppler imaging echocardiography.

Results

The distribution of NCAN, PCAN, and DCAN was 11.4%, 51.1%, and 37.5%, respectively. The proportion of LVDD increased among the groups of NCAN, PCAN, and DCAN (39.4%, 45.3%, and 68.0%, P = 0.001). Patients with DCAN had higher filling pressure (E/e′ ratio) (10.9 ± 2.7 versus 9.4 ± 2.8, P = 0.013) and impaired diastolic performance (e′) (6.8 ± 1.7 versus 8.6 ± 2.4, P = 0.004) compared with NCAN. CAN was found to be an independent risk factor for LVDD from the multivariate regression analysis (OR = 1.628, P = 0.009, 95% CI 1.131–2.344).

Conclusions

Our results indicated that CAN was an independent risk marker for the presence of LVDD in patients with diabetes. Early diagnosis and treatment of CAN are advocated for preventing LVDD in type 2 diabetes.

Sensitive detection of hemodynamic failure during orthostatic stress in patients with diabetic polyneuropathy using a mini laser Doppler blood flowmeter

Autonomic dysfunction in diabetes is serious but often underestimated. The purpose of this study was to evaluate hemodynamics within the important initial phase just after standing, which cannot be evaluated by conventional instruments for orthostatic hypotension. Earlobe blood flow (EBF), which indirectly reflects the blood pressure response on standing, was evaluated using a mini laser Doppler flowmeter during standing from the sitting position in 58 healthy controls and 56 diabetic patients categorized as without (11), mild (27), and advanced diabetic polyneuropathy (18). The response area of the EBF waveform within 30 seconds after standing was calculated. An increased response area indicates poor recovery of EBF. Response area increased significantly with the degree of neuropathy (P < .001 for linear trend). Orthostatic hypotension was detected in two patients in the mild neuropathy group. The present approach may be sensitive and practical for detecting autonomic dysfunction not detected with the conventional orthostatic test.

The association between orthostatic increase in pulse pressure and ischemic heart disease

The clinical meaning of changes in PP with posture remains unclear. We performed treadmill exercise testing on 144 subjects to diagnose ischemic heart disease, and measured the PPs in the supine and standing positions. The differences in the two PPs ranged between -35 and 45 mmHg. Eleven subjects were diagnosed with significant coronary ischemia. The differences in the PPs were significantly increased, and PP in the standing position was significantly elevated in these subjects. A large difference in the PPs in the standing and supine positions was associated with significant coronary ischemia, independent of significant covariables.

The clinical & neurophysiological study of leprosy

OBJECTIVES

The aim of this study was to evaluate neurological and neurophysiological features of leprosy.

METHODS

Seventy seven hospitalized leprosy patients (52 male, 25 female) were examined neurological and neurophysiologically between 2010 and 2012. Standard procedures were performed for evaluating sensory and motor conduction studies to all patients. Motor studies were carried out on median, ulnar, tibial and common peroneal nerves. Sensory studies were carried out on median, ulnar and sural nerves. Sympathetic skin response (SSR) recordings on both hands and feet, and the heart rate (R-R) interval variation (RRIV) recordings on precordial region were done in order to evaluate the autonomic dysfunction.

RESULTS

The mean age was 59.11±14.95 years ranging between 17 and 80 years. The mean duration of disease was 35.58±18.30 years. Clinically, the patients had severe deformity and disability. In neurophysiological examinations, sensory, motor conduction studies of the lower extremities were found to be more severely affected than upper, and sensory impairment predominated over motor. Abnormal SSRs were recorded in 63 (81.8%) cases of leprosy. Abnormal RRIVs were recorded in 41 (53.2%) cases and abnormal RRIVs with hyperventilation were recorded in 55 (71.4%) cases of leprosy. Significant differences were found between SSR and sensory conduction parameters of median, ulnar nerves as well as motor conduction parameters of median, ulnar and peroneal nerves (p<0.05).

CONCLUSION

Peripheral nervous system dysfunction is accompanied by autonomic nervous system dysfunction in leprosy patients. Sympathetic involvement may predominate over parasympathetic involvement.

Decreased circulatory response to hypovolemic stress in young women with type 1 diabetes

OBJECTIVE

Diabetes is associated with hemodynamic instability during different situations involving acute circulatory stress in daily life. Young men with type 1 diabetes have been shown to have impaired circulatory response to hypovolemic stress. The effect of type 1 diabetes on cardiovascular response to hypovolemia in young women is unknown, however.

RESEARCH DESIGN AND METHODS

Lower body negative pressure of 30 cm H2O was used to create rapid hypovolemic stress in 15 young women with type 1 diabetes (DW) and 16 healthy women (control subjects [C]). Compensatory mobilization of venous capacitance blood (capacitance response) and net fluid absorption from tissue to blood were measured with a volumetric technique. Overall cardiovascular responses and plasma norepinephrine levels were measured.

RESULTS

Capacitance response was reduced (DW, 0.67 ± 0.05; C, 0.92 ± 0.06) and developed slower in DW (P < 0.01). Capacitance response was further reduced with increasing levels of HbA1c. Fluid absorption was almost halved in DW (P < 0.01). The initial vasoconstrictor response was reduced and developed slower in DW (P < 0.05). Arterial vasoconstriction was further reduced in the presence of microvascular complications (P < 0.05).

CONCLUSIONS

DW present with decreased and slower mobilization of venous capacitance blood and decreased net fluid absorption from tissue to blood during hypovolemic circulatory stress. Collectively, this indicates that DW are prone to hemodynamic instability, especially in the presence of microvascular complications and poor glycemic control.

The skin landscape in diabetes mellitus. Focus on dermocosmetic management

Background

Some relationships are established between diabetes mellitus (DM) and a series of cutaneous disorders. Specific dermatoses are markers for undiagnosed DM. Other disorders represent supervening complications in an already treated DM patient.

Objective

To review the information about dermocosmetic care products and their appropriate use in the management and prevention of dermatoses related to DM.

Method

The peer-reviewed literature and empiric findings are covered. Owing to the limited clinical evidence available for the use of dermocosmetics, a review of the routine practices and common therapies in DM-related dermatoses was conducted.

Results

Some DM-related dermatoses (acanthosis nigricans, pigmented purpuric dermatosis) are markers of macrovascular complications. The same disorders and some others (xerosis, Dupuytren’s disease) have been found to be more frequently associated with microangiopathy. Other skin diseases (alopecia areata, vitiligo) were found to be markers of autoimmunity, particularly in type 1 DM. Unsurprisingly, using dermocosmetics and appropriate skin care has shown objective improvements of some DM-related dermatoses, such effects improve the quality of life. The most common skin manifestations of DM fall along continuum between “dry skin,” xerosis, and acquired ichthyosis, occurring predominately on the shins and feet. Dermocosmetic products improve the feeling of well-being for DM patients.

[Relationships between baroreflex gain and pulsatile stress in type 1 diabetic patients]

AIM OF THE STUDY

Cardiovascular autonomic neuropathy (CAN) and early arterial stiffness are frequent complications in type 1 diabetes. The aim of our work is to study the relationships between CAN (estimated by baroreflex gain calculation) and arterial stiffness (estimated by pulsatile stress) in type 1 diabetic patients.

PATIENTS AND METHODS

In a cross-sectional study, we calculated baroreflex gain and pulsatile stress in 167 type 1 diabetic patients and 160 matched non-diabetic subjects whose blood pressure was continuously monitored with a Finapres(®) device in a postural test (squatting test). The baroreflex gain was calculated by plotting the pulse intervals (R-R) against systolic blood pressure values during the transition phase from squatting to standing. Pulsatile stress was estimated by the pulse pressure×heart rate product. In a longitudinal study, the baroreflex gain and pulsatile stress were calculated before and after a mean follow-up of 79±33 months in type 1 diabetic patients.

RESULTS

Cross-sectional data showed a decrease in baroreflex gain and an increase in pulsatile stress in type 1 diabetic patients versus the matched non-diabetic subjects. A significant correlation between the baroreflex gain and pulsatile stress was present. Type 1 diabetic patients with lower baroreflex gain had a higher value of pulsatile stress when compared to those with higher baroreflex gain. During follow-up, a significant reduction in baroreflex gain (but without significantly increased pulsatile stress) was observed. A univariate analysis showed that the decrease of the baroreflex gain is not correlated with the time interval between the two tests, neither type 1 diabetes duration nor mean glycated hemoglobin values, but significantly with the pulsatile stress increase.

CONCLUSION

In type 1 diabetic patients, the baroreflex gain is decreased and the pulsatile stress is increased when these markers are compared to age-matched non-diabetic subjects. There is a relationship between indices of CAN and arterial stiffness. Nevertheless, the baroreflex gain (marker of CAN) is impaired earlier than the pulsatile stress in this type 1 diabetic population with inadequate glycaemic control.

The influence of autonomic dysfunction associated with aging and type 2 diabetes on daily life activities

Type 2 diabetes (T2D) and ageing have well documented effects on every organ in the body. In T2D the autonomic nervous system is impaired due to damage to neurons, sensory receptors, synapses and the blood vessels. This paper will concentrate on how autonomic impairment alters normal daily activities. Impairments include the response of the blood vessels to heat, sweating, heat transfer, whole body heating, orthostatic intolerance, balance, and gait. Because diabetes is more prevalent in older individuals, the effects of ageing will be examined. Beginning with endothelial dysfunction, blood vessels have impairment in their ability to vasodilate. With this and synaptic damage, the autonomic nervous system cannot compensate for effectors such as pressure on and heating of the skin. This and reduced ability of the heart to respond to stress, reduces autonomic orthostatic compensation. Diminished sweating causes the skin and core temperature to be high during whole body heating. Impaired orthostatic tolerance, impaired vision and vestibular sensing, causes poor balance and impaired gait. Overall, people with T2D must be made aware and counseled relative to the potential consequence of these impairments.

Squatting, a posture test for studying cardiovascular autonomic neuropathy in diabetes

Cardiovascular autonomic neuropathy (CAN) is a frequent complication of diabetes mellitus, which is associated with increased morbidity and mortality. It involves both the parasympathetic and sympathetic nervous systems, and may be diagnosed by classical dynamic tests with measurements of heart rate (HR) and/or arterial blood pressure (BP). An original squat test (1-min standing, 1-min squatting, 1-min standing) was used with continuous monitoring of HR and BP, using a Finapres(®) device. This active test imposes greater postural stress than the passive head-up tilt test, and provokes large changes in BP and HR that can be analyzed to derive indices of CAN. In healthy subjects, squatting is associated with BP increases and HR decreases (abolished by atropine: SqTv index), whereas the squat-stand transition is accompanied by a deep but transient drop in BP associated with sympathetic-driven tachycardia (abolished by propranolol: SqTs index). In diabetic patients with CAN, BP increases are accentuated during squatting whereas reflex bradycardia is reduced. When standing from squatting position, the fall in BP tends to be more pronounced and orthostatic hypotension more prolonged, while reflex tachycardia is markedly dampened. The baroreflex gain, similar to that calculated during pharmacological testing with vasodilator/vasopressor agents, can be derived by plotting pulse intervals (R-R) against systolic BP levels during the biphasic response following the squat-stand transition. The slope, which represents baroreflex sensitivity, is significantly reduced in patients with CAN. This discriminatory index allows study of the natural history of CAN in a large cohort of diabetic patients.

Correlations between aortic stiffness and parasympathetic autonomic function in healthy volunteers

Cardiovascular autonomic dysfunction and alterations in vascular elasticity are known complications of several disorders, including diabetes mellitus, hypertension, hypercholesterolemia, aging, and chronic kidney disease. The current study was designed to test whether a relationship existed between pulse wave velocity (PWV), augmentation index (AIx), aortic elastic properties, and cardiovascular autonomic function in healthy volunteers. The study comprised 25 healthy volunteers, whose aortic strain, distensibility, and stiffness index were measured by echocardiography, whereas PWV and AIx were evaluated by Arteriograph (TensioMed, Budapest, Hungary) in all cases. Autonomic function was assessed by means of 5 standard cardiovascular reflex tests. We found that heart rate response to deep breathing, as the most reproducible cardiovascular reflex test to characterize parasympathetic function, showed low to moderate correlations with PWV (r = -0.431, p = 0.032), aortic strain (r = 0.594, p = 0.002), distensibility (r = 0.407, p = 0.043), and stiffness index (r = -0.453, p = 0.023). Valsalva ratio and autonomic neuropathy score (ANS) correlated with PWV (r = -0.557, p = 0.004 and r = -0.421, p = 0.036, respectively) and AIx (r = -0.461, p = 0.020 and r = -0.385, p = 0.057, respectively), while ANS correlated with even aortic stiffness index (r = -0.457, p = 0.022). Cardiovascular reflex tests mainly characterizing sympathetic function had no correlation with aortic stiffness parameters (p = NS for all correlations). Correlations exist between parameters characterizing aortic elasticity and parasympathetic autonomic function, as shown by standard cardiovascular reflex tests in healthy volunteers.

Pulsatile stress in middle-aged patients with type 1 or type 2 diabetes compared with nondiabetic control subjects

OBJECTIVE

Arterial pulse pressure is considered to be an independent cardiovascular risk factor. We compared pulse pressure during an active orthostatic test in middle-aged patients with type 1 diabetes and with type 2 diabetes and corresponding nondiabetic control subjects.

RESEARCH DESIGN AND METHODS

Forty patients with type 1 diabetes (mean age 50 years, diabetes duration 23 years, and BMI 23.0 kg/m2) were compared with 40 nonhypertensive patients with type 2 diabetes (respectively, 50 years, 8 years, and 29.7 kg/m2). Patients taking antihypertensive agents or with renal insufficiency were excluded. All patients were evaluated with a continuous noninvasive arterial blood pressure monitoring (Finapres) in standing (1 min), squatting (1 min), and again standing position (1 min). Patients with type 1 or type 2 diabetes were compared with two groups of 40 age-, sex- and BMI-matched healthy subjects.

RESULTS

Patients with type 1 diabetes and patients with type 2 diabetes showed significantly higher pulse pressure, heart rate, and double product of pulse pressure and heart rate (PP×HR) (type 1: 5,263 vs. 4,121 mmHg/min, P=0.0004; type 2: 5,359 vs. 4,321 mmHg, P=0.0023) levels than corresponding control subjects. There were no significant differences between patients with type 1 diabetes and type 2 diabetes regarding pulse pressure (59 vs. 58 mmHg), heart rate (89 vs. 88/min), and PP×HR (5,263 vs. 5,359 mmHg/min).

CONCLUSIONS

Patients with type 1 diabetes have increased levels of peripheral PP, an indirect marker of arterial stiffness, and PP×HR, an index of pulsatile stress, comparable to those of nonhypertensive patients with type 2 diabetes at similar mean age of 50 years.

Circadian blood pressure variability in type 1 diabetes subjects and their nondiabetic siblings - influence of erythrocyte electron transfer

BACKGROUND

Normotensive non-diabetic relatives of type 1 diabetes (T1D) patients have an abnormal blood pressure response to exercise testing that is associated with indices of metabolic syndrome and increased oxidative stress. The primary aim of this study was to investigate the circadian variability of blood pressure and the ambulatory arterial stiffness index (AASI) in healthy siblings of T1D patients vs healthy control subjects who had no first-degree relative with T1D. Secondary aims of the study were to explore the influence of both cardiovascular autonomic function and erythrocyte electron transfer activity as oxidative marker on the ambulatory blood pressure profile.

METHODS

Twenty-four hour ambulatory blood pressure monitoring (ABPM) was undertaken in 25 controls, 20 T1D patients and 20 siblings. In addition to laboratory examination (including homeostasis model assessment of insulin sensitivity) and clinical testing of autonomic function, we measured the rate of oxidant-induced erythrocyte electron transfer to extracellular ferricyanide (RBC vfcy).

RESULTS

Systolic blood pressure (SBP) midline-estimating statistic of rhythm and pulse pressure were higher in T1D patients and correlated positively with diabetes duration and RBC vfcy; autonomic dysfunction was associated with diastolic BP ecphasia and increased AASI. Siblings had higher BMI, lower insulin sensitivity, larger SBP amplitude, and higher AASI than controls. Daytime SBP was positively, independently associated with BMI and RBC vfcy. Among non-diabetic people, there was a significant correlation between AASI and fasting plasma glucose.

CONCLUSIONS

Siblings of T1D patients exhibited a cluster of sub-clinical metabolic abnormalities associated with consensual perturbations in BP variability. Moreover, our findings support, in a clinical setting, the proposed role of transplasma membrane electron transport systems in vascular pathobiology.

Changes in pulse pressure, heart rate and the pulse pressure x heart rate product during squatting in Type 1 diabetes according to age

AIMS

We assessed changes in pulse pressure and heart rate during a squatting test, as indirect markers of arterial stiffness and cardiovascular autonomic neuropathy, respectively, according to age and sex in patients with Type 1 diabetes mellitus.

METHODS

We evaluated 160 diabetic patients, divided into four groups of 20 men and 20 women according to age (G1, 20-30 years old; G2, 31-40 years old; G3, 41-50 years old; and G4, 51-60 years old), and 160 non-diabetic matched control subjects. Each subject underwent a 3 min posture test (standing-squatting-standing) with continuous measurement of arterial blood pressure and heart rate by a Finapres device. Overall values throughout the test, baseline levels in initial standing position and squatting-induced changes in pulse pressure, heart rate and the pulse pressure x heart rate product were compared between diabetic patients and healthy control subjects.

RESULTS

In the standing position, a greater increase in pulse pressure and lower reduction in heart rate with age led to a significantly higher pulse pressure x heart rate product in diabetic patients compared with control subjects. In the squatting position, a more marked pulse pressure increase in the absence of appropriate reduction in heart rate resulted in a greater rise in the pulse pressure x heart rate product in diabetic patients than in healthy subjects. No major differences were noted between the sexes, with the exception of a stronger relationship between pulse pressure and age in the female population with diabetes. Squatting-derived indices of cardiovascular autonomic neuropathy were also noted with increasing age in diabetic patients.

CONCLUSIONS

The marked increase in the pulse pressure x heart rate product ('pulsatile stress') according to age, combined with cardiovascular autonomic neuropathy, may contribute to the higher cardiovascular risk of patients with Type 1 diabetes.