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Biomedical subjects

J Paries

Publications and source records attributed to J Paries.

At least 19 recordsLinked to original sources
PubMed2005

Fas/Fas-Ligand pathway is impaired in patients with type 2 diabetes. Influence of hypertension and insulin resistance.

OBJECTIVES: In type 2 diabetic patients with no cardiac history or symptoms, 1) to evaluate whether the soluble forms of Fas (sFas) and Fas-ligand (sFasL), involved in apoptosis, may be markers of silent coronary disease or related to hypertension or microangiopathic complications; 2) to examine the effect of short-term glycemic control on sFas and sFasL. METHODS: (1) sFas and sFasL were measured with the ELISA method in 44 asymptomatic diabetic patients, 33 with hypertension, and with a normal myocardial scintigraphy (n=14), with silent myocardial ischemia (SMI) and without (n=15) or with (n=15) significant coronary stenoses; and in 14 controls; (2) sFas and sFasL were measured in 15 poorly controlled diabetic patients before and after 7 days of CSII treatment. RESULTS: (1) sFas and sFasL differed in the four groups of patients (p=0.003 each). sFas was significantly higher in the patients with SMI without (p=0.035) and with coronary stenoses (p=0.002) than in the control group. sFasL was lower in the three groups of diabetic patients (p<0.05 each) than in control group. In the diabetic population, sFas correlated positively with hypertension (p=0.021), and sFasL negatively with hypertension (p=0.027) and HOMA index in the non-insulin treated patients (p=0.049); (2) sFas did not differ before or after CSII, and there was a marginal decrease in sFasL. CONCLUSION: Fas-mediated apoptosis is involved in type 2 diabetes and might be associated with hypertension and/or its vascular consequences. sFasL might be affected by insulin resistance. sFas and sFasL are not effective markers of SMI.

Adult↗
PubMed2005

High prevalence and severity of cardiac autonomic neuropathy in Vietnamese diabetic patients.

AIMS: Malnutrition is frequent in Vietnamese people and may influence cardiac autonomic neuropathy (CAN). The aim of the present study was to investigate cardiac autonomic function in healthy subjects living in Vietnam and the prevalence of CAN in Vietnamese diabetic patients. METHODS: One hundred and five diabetic patients (BMI = 19.8 +/- 0.3 kg/m(2)), 50 Type 1 and 55 Type 2, living in Hué (Vietnam) were selected and compared with 60 non-diabetic healthy Vietnamese controls (BMI = 20.8 +/- 0.2 kg/m(2)) and also European controls. CAN function was evaluated by five standardized tests: three tests for heart rate variations (HRV) which depend mainly on parasympathetic activity, and two tests for blood pressure (BP) response which depend mainly on sympathetic activity. RESULTS: With age taken into account, 41 of the 60 Vietnamese controls had at least mild CAN, as defined by one abnormal test for HRV when compared with the European control series, and 11 of them had two or three abnormal tests. Among the Vietnamese control men, those with abnormal HRV had lower BMI than those without (P = 0.036). Seven Vietnamese controls had postural hypotension and 16 had an abnormal BP response to the handgrip test. Compared with the Vietnamese controls, 71 diabetic patients (67.6%), 40 Type 1 and 31 Type 2, had at least mild CAN, 37 of them had two or three abnormal HRV tests, and 56 diabetic patients (53.3%) had an abnormal BP response to the sympathetic tests. Abnormal HRV were associated with significantly lower BMI, waist and hip circumferences, longer diabetes duration and higher fasting blood glucose. In the logistic regression analyses, abnormal HRV were associated significantly with duration of diabetes and BMI in patients with Type 2 diabetes. CONCLUSIONS: Cardiac autonomic dysfunction is frequent in normal Vietnamese subjects. CAN appears to be a more frequent complication of diabetes in Vietnam than in Western countries and diabetic parasympathetic dysfunction is frequently associated with sympathetic disorders. This confirms the deleterious effect a poor nutritional state has on cardiac autonomic function.

Adult↗
PubMed2004

Detecting silent coronary stenoses and stratifying cardiac risk in patients with diabetes: ECG stress test or exercise myocardial scintigraphy?

AIMS: To determine whether performing a myocardial scintigraphy immediately after a maximal electrocardiogram (ECG) stress test is effective in detecting silent coronary stenoses and predicting cardiovascular events. METHODS: Asymptomatic patients (n = 262) aged 57.6 +/- 8.8 years, with diabetes for 12.0 years (5-39) [median (range)] and no history of a cardiac event, underwent a maximal ECG stress test followed by a myocardial scintigraphy. The patients with an abnormal ECG stress test or abnormal imaging underwent a coronary angiography. Cardiac events were assessed in 250 (95.4%) patients followed for 37.8 months (3-101). RESULTS: The ECG stress test was abnormal in 54 patients. Among them, 18 had coronary stenoses and seven had a cardiac event. Despite a normal ECG stress test, the myocardial scintigraphy was abnormal in 42 additional patients, including 16 patients with coronary stenoses. Four of these 42 patients experienced a cardiac event. Follow-up showed a poor prognosis in subjects who were abnormal on the two tests. Univariate predictors of the 15 cardiac events were the ECG stress test [odds ratio (OR) 3.9, 95% confidence interval (CI) 1.3, 11.4, P = 0.008], myocardial scintigraphy (OR 3.8, 95% CI 1.3, 11.0, P = 0.009), coronary stenoses (OR 26.6, 95% CI 7.6, 90.7, P < 0.001), and peripheral or carotid occlusive arterial disease (OR 9.5, 95% CI 2.1, 42.5, P < 0.001). CONCLUSIONS: In the asymptomatic patients with diabetes, combining a myocardial scintigraphy with a maximal ECG stress test is effective in detecting more patients with coronary stenoses and predicting cardiovascular events. However, the ECG stress test has a good negative predictive value for cardiac events (97%), is cheaper, and should therefore be proposed first.

Cardiovascular Diseases↗
PubMed2003

Are silent coronary stenoses predictable in diabetic patients and predictive of cardiovascular events?

OBJECTIVES: We have previously shown that silent coronary stenoses (CS) were predictors of subsequent major cardiac events in diabetic patients with silent myocardial ischemia (SMI). The aim of this study was to determine their correlates and their prognostic value for other cardiovascular events. METHODS: 362 asymptomatic diabetic patients, without prior myocardial infarction, with > or =1 additional risk factor and a normal resting electrocardiogram underwent a myocardial scintigraphy to detect SMI. The patients with SMI subsequently underwent a coronary angiography to detect CS. A total of 345 (95.3%) patients were followed up for 41 +/- 24 months with regard to the occurrence of stroke, gangrene or a peripheral revascularization procedure, exercise occurrence of angina, and nonfatal arrhythmia. RESULTS: 121 patients had SMI and 44 had CS. The univariate correlates of CS were age > 65 years (Odds Ratio 2.1 [CI 95%: 1.1-4.0]; p=0.021), male gender (OR 3.1 [1.5-6.3]; p=0.001), smoking (OR 2.8 [1.4-5.6]; p=0.004), > or =2 risk factors (OR 2.1 [1.09-4.09]; p=0.024) and peripheral arterial disease (OR 3.2 [1.2-8.7]; p=0.018). Logistic regression showed that age > 65 years (p=0.034), male gender (p=0.001) and > or =2 risk factors (p=0.013) were independently associated with the presence of CS. The univariate predictors of the 16 minor events were peripheral arterial disease (OR 8.8 [2.7-28.5]; p<0.001), CS (OR 4.9 [1.7-14.2]; p=0.002), SMI (OR 3.7, [1.3-10.5]; p=0.009) and smoking (OR 3.2 [1.1-9.2]; p=0.024). In the multivariate analysis, arterial occlusive disease (p<0.001), smoking (p<0.036) and CS (p=0.044) were independent predictors of events. CONCLUSION: Silent CS predict major cardiac events but also other cardiovascular events and are more common in diabetic patients > 65 years-old, of male gender and with > or =2 risk factors.

Aged↗
PubMed2002

Laparoscopic ultrasonography is a complement to cholangiography for the detection of choledocholithiasis at laparoscopic cholecystectomy.

BACKGROUND: Intraoperative cholangiography and laparoscopic ultrasonography are both used in the detection of common bile duct stones at laparoscopic cholecystectomy. The aim of this prospective study was to determine whether laparoscopic ultrasonography has an alternative or a complementary role with respect to cholangiography in achieving this end. METHODS: The biliary trees of 900 patients undergoing laparoscopic cholecystectomy were examined routinely by the two methods. The diagnostic power of each investigation and of the two techniques in combination was evaluated. The statistical non-random concordance between the two methods was also determined. RESULTS: Laparoscopic ultrasonography was performed in all 900 patients. Cholangiography was performed in 762 (85 per cent). The mean (range) duration was 9.8 (4-21) min for laparoscopic ultrasonography and 17.6 (7-42) min for cholangiography. For the detection of common bile duct stones, with a kappa coefficient of 0.57 (95 per cent confidence interval (c.i.) 0.43 to 0.71), the non-random concordance between the two methods was considered to be fair to good. The sensitivity of laparoscopic ultrasonography was 0.80 (95 per cent c.i. 0.65 to 0.91) and its specificity was 0.99 (95 per cent c.i. 0.98 to 1.00). The respective values for cholangiography were 0.75 (95 per cent c.i. 0.59 to 0.87) and 0.99 (95 per cent c.i. 0.98 to 1.00). The examinations combined had a sensitivity of 0.95 (95 per cent c.i. 0.86 to 0.99) and a specificity of 0.98 (95 per cent c.i. 0.96 to 1.00). CONCLUSION: Laparoscopic ultrasonography and intraoperative cholangiography are complementary, as the combination of both methods maximizes the intraoperative detection of choledocholithiasis.

Adult↗
PubMed2001

Treatment of reflex sympathetic dystrophy with pamidronate: 29 cases.

OBJECTIVE: To evaluate the efficacy of treatment with pamidronate in reflex sympathetic dystrophy (RSD) refractory to previous treatment. METHODS: We studied the response (disappearance of pain and functional improvement) to pamidronate (60 mg/day for 3 days) in 29 patients with RSD refractory to previous treatment for at least 14 days. RESULTS: On day 45, complete pain disappearance was observed in 86.2% of patients and functional improvement in 70%. The mean delay until the pain disappeared was 20+/-14 days and the delay until functional improvement was observed was 29+/-18 days. The mean delay of functional improvement was shorter in patients with post-traumatic RSD. Multivariate analysis did not reveal any factor predictive of response to treatment. Six (20.7%) patients suffered from side-effects (fever, diarrhoea). CONCLUSION: Pamidronate appeared to be effective in the treatment of refractory RSD; however, these results need to be confirmed by a controlled placebo study.

Adult↗
PubMed2001

Predictive value of cardiac autonomic neuropathy in diabetic patients with or without silent myocardial ischemia.

OBJECTIVE: The aim of this study was to determine the predictive value of silent myocardial ischemia (SMI) and cardiac autonomic neuropathy (CAN) in asymptomatic diabetic patients. RESEARCH DESIGN AND METHODS: We recruited 120 diabetic patients with no history of myocardial infarction or angina, a normal 12-lead electrocardiogram (ECG), and two or more additional risk factors. SMI assessment was carried out by means of an ECG stress test, a thallium-201 myocardial scintigraphy with dipyridamole, and 48-h ECG monitoring. CAN was searched for by standardized tests evaluating heart rate variations. Accurate follow-up information for 3-7 years (mean 4.5) was obtained in 107 patients. RESULTS: There was evidence of SMI in 33 patients (30.7%). CAN was detected in 33 of the 75 patients (38.9%) who were tested, and a major cardiac event occurred in 11 of them. Among these 75 patients, the proportion of major cardiac events in the SMI+ patients was not significantly higher than that in the SMI- patients (6 of 25 vs. 5 of 50 patients), whereas it was significantly higher in the CAN+ patients than in the CAN- patients (8 of 33 vs. 3 of 42 patients; P = 0.04), with a relative risk of 4.16 (95% CI 1.01-17.19) and was the highest in the patients with both SMI and CAN (5 of 10 patients). After adjusting for SMI, there was a significant association between CAN and major cardiac events (P = 0.04). CONCLUSIONS: In asymptomatic diabetic patients, CAN appears to be a better predictor of major cardiac events than SMI. The risk linked to CAN appears to be independent of SMI and is the highest when CAN is associated with SMI.

Adult↗
PubMed2001

Lower-limb vascularization in diabetic patients. Assessment by thallium-201 scanning coupled with exercise myocardial scintigraphy.

OBJECTIVE: To investigate, by thallium-201 scanning, circulation in the muscles of the lower limb (LL) in diabetic patients without clinical peripheral vascular disease but with a high cardiovascular risk profile. RESEARCH DESIGN AND METHODS: A total of 80 diabetic patients (76 patients with type 2 diabetes, mean age 57.3 years, duration of diabetes 13.0 +/- 7.5 years) with more than one additional cardiovascular risk factor but no claudication were investigated. After stress testing, 1.5 MBq/kg thallium-201 was administered to perform myocardial single-photon emission computed tomography followed by LL scanning. Muscle blood flow was considered abnormal if the asymmetry in thallium-201 uptake between the two buttocks and/or thighs and/or calves was > 10%. RESULTS: Muscle perfusion defects were found in 42% of the patients, mainly in the calves. These defects correlated with retinopathy (P = 0.042) and the HbA1c level (P = 0.044). In patients with defects in the buttock and/or thigh, the prevalence of nephropathy and retinopathy was higher than in those with isolated defects in the calf (P = 0.032 and 0.023, respectively). CONCLUSIONS: This study suggests that LL scanning coupled with myocardial scintigraphy is a convenient method of investigating peripheral muscle circulation. Proximal perfusion defects in patients without clinical arterial disease are associated with increased prevalence of retinopathy and nephropathy and, therefore, may be due to microvascular disease of LL muscle. Distal defects may indicate silent macrovascular disease of the LL.

Adult↗
PubMed2001

[Relationship between vasosympathetic activity and insulin resistance in normotensive and mildly hypertensive obese patients].

Several studies have well demonstrated that obesity is associated with changes in cardiovascular vagosympathetic activity. The aim of the present work was to evaluate this activity in normotensive and in mildly hypertensive obese patients, and to correlate this activity with clinical and biological indexes of insulin resistance. Heart rate (HR) and systolic blood pressure (sBP) were examined by spectral analysis in 70 normotensive obese patients (group 1), 32 mildly hypertensive obese patients (group 2), and 21 controls. The high frequency peak of HR variations at a controlled breathing rate (vagal activity) was significantly reduced in both groups (p < 0.001). The mid frequency peak of sBP in the standing position (sympathetic activity) was similar in both groups and in the control group. In groups 1 and 2, the high frequency peak correlated negatively with age (p = 0.005 and 0.034 respectively). In group 1, the mid frequency peak correlated positively with fat mass, fasting plasma insulin and triglyceride levels, and insulin resistance index (p < or = 0.03). In group 2, the mid frequency peak correlated positively with fasting insulin and insulin resistance index (p = 0.006 and 0.007 respectively). This study shows that, in obese patients: 1. cardiac vagal activity is reduced in normotensive and mildly hypertensive subjects; 2. vascular sympathetic activity is unchanged in means but may be increased as a consequence of adiposity, hyperinsulinemia and insulin resistance, and this increase is likely to be involved in the increase of blood pressure.

Adult↗
PubMed2000

Effects of isoflurane on bacterial growth.

Anaesthetic agents have been implicated in the development of postoperative pneumonia, but the direct effect of volatile anaesthetics on bacterial growth has given contradictory results. The effects of isoflurane on the growth of Staphylococcus aureus and Escherichia coli were investigated under conditions similar to those of clinical practice, using standardized microbiological methods. An open anaesthetic circuit was adjusted to the normal ventilatory settings of an adult patient. A spray, installed on the inspiratory side of the circuit, ensured the delivery of isoflurane at 1.5 minimal alveolar concentration. The bacterial strains studied were both wild-type and reference strains. Bacterial inoculums were prepared to obtain a bacterial exponential growth of 10(3) colony-forming units per mL in 10 mL of nutritive broth. Each strain was studied with and without exposure to isoflurane and measured by the usual criteria of bacterial growth, and by bacterial regrowth after exposure to isoflurane. Under experimental conditions close to clinical practice, exposure to isoflurane did not alter bacterial growth of S. aureus and E. coli, or their bacterial regrowth when isoflurane exposure is over.

Anesthesia, Inhalation↗
PubMed1999

Haemodynamic response to an isometric exercise test in obese patients: influence of autonomic dysfunction.

OBJECTIVE: To investigate blood pressure (BP) and heart rate (HR) responses to an isometric exercise test in obese non diabetic patients and to correlate the results with vagal function and plasma insulin concentration. SUBJECTS: 63 obese patients, 36 of whom had abnormal cardiac parasympathetic control (PS+), and 35 healthy control subjects. METHODS: Analysis of HR variations during three standardized tests: deep-breathing, lying-to-standing and Valsalva. Isometric contraction (handgrip) for 5 min. RESULTS: In the PS+ obese patients, resting HR and body mass index (BMI) were significantly higher than in the PS- subjects and there was a trend to higher plasma insulin concentrations. Age-matched comparison showed that during the handgrip test, the increase in HR at the first minute was significantly higher in the PS- obese patients than in the controls. The increase in BP was significantly lower in the PS+ obese patients than in age-and-BMI-matched PS- obese patients. CONCLUSION: These data suggest that 1) there is an increase in cardiac vagal tone in PS- obese patients, since the early increase in HR at 1 min of the handgrip test, results from the withdrawal of vagal tone; 2) BP response to an isometric contraction is impaired in PS+ obese patients due to a lower sympathetic activation; 3) high plasma insulin concentrations may also contribute to limiting the BP response; and 4) autonomic disorders may account for alterations in the haemodynamic changes during exercise.

Adolescent↗
PubMed1999

Determinants of echocardiographically measured left ventricular mass in diabetic patients with or without silent myocardial ischaemia.

Left ventricular hypertrophy (LVH) is a recognized independent risk factor for cardiovascular morbidity and mortality. The purpose of this study was to assess the determinants of left ventricular mass index (LVMI), according to the presence or absence of silent myocardial ischaemia (SMI), in diabetic patients with at least two additional risk factors but with no known coronary artery disease. Eighty diabetic patients (14 Type 1 and 66 Type 2) were studied, and LVMI was measured echocardiographically. Three non-invasive tests (the ECG stress test, thallium-201 myocardial scintigraphy with intravenous dipyridamole infusion, and ambulatory 48-h ECG monitoring) were performed on all patients. Forty-five percent of patients had LVH (LVMI > or = 110 g/m2 in men and > or = 106 g/m2 in women). Twenty-six patients (37%) had SMI assessed on at least one of the non-invasive tests, 7 of whom had significant coronary stenoses on angiography. LVMI was significantly higher in patients with coronary stenoses on angiography than in those with SMI but without coronary stenoses or in those without SMI (p < 0.05), and was correlated with systolic blood pressure. In patients free of SMI, LVMI correlated with creatininemia. In patients with SMI and normal coronary arteries on angiography, LVMI correlated with the waist/hip girth ratio, the log urinary albumin excretion rate and the red blood cell filtration index (a rigidity index). This study suggests that LVH is very frequent in diabetic patients and that the main factor contributing to the increase of LVMI differs according to the presence or absence of SMI and coronary stenoses: volume load in patients free of SMI, microcirculatory disorders in those with SMI but with normal coronary arteries, and blood pressure in those with coronary stenoses.

Analysis of Variance↗
PubMed1999

[Insulin resistance and alteration of cardiac vagal activity in obese patients].

We have previously shown that alterations of vagal control of heart rate variations are found in more than half of non diabetic obese subjects (Int J Obes 1995) and are associated with a more severe insulin resistance in noninsulin dependent diabetic patients (Metabolism 1998). The aim of this study was to examine whether parasympathetic alterations are also associated with a more severe insulin resistance in non diabetic obese subjects. 245 obese subjects (BMI = 34.2 +/- 0.4 kg/m2) aged 38.6 +/- 0.8 years, with a normal oral glucose tolerance test were included. Parasympathetic activity was evaluated by heart rate variations during three standardised tests: Valsalva, deep-breathing and active lying-to-standing, with age being taken into account. The Valsalva maneuver was abnormal in 17.5%, the deep-breathing test in 18% and the lying-to-standing test in 30.3% of the cases. One hundred and thirty subjects (52.1%) had at least one abnormal test. Compared with those with three normal tests, the obese subjects with parasympathetic alterations had very similar BMI and blood pressure, but significantly higher values of heart rate (75.5 +/- 1.4 vs 71.3 +/- 1.1 beats/min, p = 0.02), fasting blood glucose (5.0 +/- 0.1 vs 4.8 +/- 0.1 mmol/L, p = 0.03) and plasma insulin (98 +/- 6 vs 82 +/- 4 pmol/L, p = 0.03). In the whole series of obese subjects, heart rate variations during the deep-breathing and lying-to-standing tests correlated negatively with blood glucose (p = 0.001 and p = 0.03 respectively), and during the deep-breathing test they correlated negatively with the waist/hip ratio (p = 0.004). This data suggests that cardiac parasympathetic alterations should take part in the insulin-resistance syndrome and might account for the poor cardiovascular prognosis linked to this syndrome.

Adult↗
PubMed1998

Influence of parasympathetic dysfunction and hyperinsulinemia on the hemodynamic response to an isometric exercise in non-insulin-dependent diabetic patients.

The handgrip test has long been used as a test for investigating cardiac autonomic neuropathy in diabetic patients. However, the factors involved in the hemodynamic response to the handgrip test have not been thoroughly studied. The aim of this study was to investigate blood pressure (BP) and heart rate (HR) responses to an isometric test in non-insulin-dependent diabetics (NIDDs) and to correlate the results with vagal function evaluated by three standardized tests and with plasma insulin levels. Fifty-five NIDDs, 35 of whom had one to three abnormal parasympathetic tests (PS+), were compared with 10 healthy control subjects. Fasting and postprandial plasma insulin levels were significantly higher in the PS+ than in the PS- patients. Resting HR correlated significantly with log fasting and postprandial insulin. In PS+ NIDDs, resting HR was significantly higher than in PS- patients. Age-matched comparisons also showed that resting systolic BP was significantly higher in PS+ patients than in controls. In PS- patients, the mean acceleration of HR was significantly higher than in the control group from the second to the fifth minute, and the BP response was also higher than in controls. These data suggest that (1) sympathetic response to an isometric exercise is increased in PS- NIDDs; (2) cardiac parasympathetic dysfunction is associated with a more severe insulin resistance; and (3) the subsequent higher plasma insulin level may contribute to the increase in resting HR and BP through sympathetic activation while limiting the hemodynamic response to an isometric exercise through its vasodilative effect.

Blood Pressure↗
PubMed1997

Hyperinsulinemia and hypofibrinolysis: effects of short-term optimized glycemic control with continuous insulin infusion in type II diabetic patients.

A defect in the fibrinolytic system results from an increase in type 1 plasminogen activator inhibitor (PAI-1) in diabetes. It can be considered an independent risk factor for the development of cardiovascular disease. In obese and type II diabetic patients, plasma PAI-1 level correlates with fasting insulinemia. However, during the euglycemic clamp, acute hyperinsulinemia does not increase PAI-1 production. The present study was undertaken to investigate the effect of optimized glycemic control by continuous subcutaneous insulin infusion (CSII) on the hypofibrinolytic state for 14 days in 16 type II diabetic patients with poor metabolic control despite maximal oral antidiabetic treatment. Plasma PAI-1 activity levels decreased from 13.38 +/- 2.85 IU/mL to 6.77 +/- 1.81 IU/mL (P = .002) during CSII, along with a concurrent improvement in insulin sensitivity (index obtained by basal glycemia-nadir glycemia/basal glycemia) during the insulin sensitivity test (0.121 +/- 0.03 v 0.057 +/- 0.02, P = .02). These results suggest that insulin resistance rather than hyperinsulinism may be involved in the hypofibrinolytic state in type II diabetic patients. The positive correlation between the changes in triglycerides and in PAI-1 activity (r = .589, P = .026) strongly suggests a role for triglycerides in the impairment of fibrinolysis, which could be a link between insulin resistance and hypofibrinolysis.

Blood Glucose↗
PubMed1997

[Alteration of cardiovascular vagosympathetic control evaluated by spectral analysis of variations of heart rate and blood pressure in obesity].

Several studies suggest alterations of parasympathetic and sympathetic control in obesity. We have already shown that more than 40% of non diabetic obese subjects have alterations of parasympathetic control of heart rate (HR) variations. The present study aimed to investigate parasympathetic and sympathetic cardiovascular control by using spectral analysis. Sixty-two non diabetic obese subjects were compared to 38 sex-matched healthy controls. Spectral analysis was performed by Anapres system and identified two particular peaks: the one of high frequency (0.20-0.25 Hz) for heart rate variations during controlled breathing which depends on parasympathetic activity, the other of low frequency (around 0.10 Hz) for systolic BP variations in the standing position which mainly depend on sympathetic activity. In control subjects the amplitude of the high frequency peak (r = -0.556, p < 0.0001) but not the amplitude of the low frequency peak correlated negatively with age. In the obese subjects both the high and low frequency peaks correlated negatively with age (r = -0.249; p = 0.05 and r = -0.289, p = 0.036 respectively) and did not correlate with body mass index. The high frequency peak was significantly lower than in controls (4.80 +/- 3.37 (SD) vs 8.38 +/- 4.14; p < 0.0001). In the 25 obese subjects over 40 years the low frequency peak was also significantly lower than in controls (10.00 +/- 3.10 vs 11.95 +/- 4.25; p < 0.05). This study suggests that 1) age must be taken into account when interpreting the cardiovascular parameters under vagosympathetic control; 2) in non diabetic obese subjects vagal activity is decreased and in those over 40 years sympathetic activity is also decreased.

Adolescent↗
PubMed1997

Silent myocardial ischaemia and left ventricle hypertrophy in diabetic patients.

The purpose of this study was to evaluate the ability of three noninvasive techniques to detect silent myocardial ischaemia and analyse the factors associated with this condition, particularly left ventricular hypertrophy, in diabetic patients. An ECG stress test, a thallium-201 myocardial scintigraphy with dipyridamole intravenous infusion, ambulatory 48 h ECG monitoring and an echocardiographic study were performed in 92 diabetic patients without cardiac symptoms but with > or = 2 additional cardiovascular risk factors. At least one of these tests was positive in 28 patients (30.4%), suggesting silent myocardial ischaemia. Twenty-four of these patients had a coronary angiography which showed significant coronary stenosis in only 9 cases. An accurate echocardiographic tracing was obtained in 79 patients, particularly in 7 of the 9 with coronary stenosis. Left ventricular hypertrophy was detected in 34 patients, 6 of whom had coronary stenosis. In patients with left ventricular hypertrophy, the positive predictive values of myocardial scintigraphy and the ECG stress test were respectively 50% and 100%, as compared to only 33% and 11% in those without hypertrophy. In summary, coronary stenoses were found in < 10% of asymptomatic diabetic patients with > or = 2 cardiovascular risk factors, but more frequently in individuals with left ventricular hypertrophy. Thus, silent myocardial ischaemia should be searched for first in diabetic patients with hypertrophy, for which the stress test was the most accurate detection method in this study.

Adult↗