Biomedical subjects

J S Viikari

Publications and source records attributed to J S Viikari.

At least 19 recordsLinked to original sources

PubMed2001

Reduced myocardial flow reserve relates to increased carotid intima-media thickness in healthy young men.

Increased carotid artery wall thickness and lipoprotein oxidation are key early events in atherosclerosis. To test the hypothesis that reduced myocardial flow reserve is a marker of subclinical atherosclerosis, we examined the relationships between flow reserve and carotid artery intima-media thickness (IMT) in young men free from coronary heart disease. Basal and dipyridamole stimulated coronary blood flow was measured using positron emission tomography (PET) in 55 healthy men aged 36+/-4 years. Myocardial flow reserve was calculated as the ratio of stimulated flow to basal flow. The mean carotid artery IMT was measured using high-resolution ultrasound. Oxidised LDL was measured as baseline LDL diene conjugation. Myocardial flow reserve decreased across the quartiles of increasing IMT (P=0.006), and was 5.2+/-1.9 in the lowest quartile for IMT and 3.7+/-1.2 in the highest (P=0.04, I vs. IV quartile). In univariate analysis, oxidised LDL correlated inversely with flow reserve (r=-0.35, P=0.01) and directly with IMT (r=0.51, P<0.001). The association between flow reserve and IMT remained significant (P< or =0.01) in multivariate regression model including age, blood pressure, left ventricular mass, ox-LDL, total cholesterol, HDL-cholesterol and triglycerides as covariates. These data support the concept that reduced myocardial flow reserve reflects subclinical atherosclerosis in asymptomatic subjects, and suggest that increased lipoprotein oxidation is directly related to early structural and functional atherosclerotic vascular changes.

Adult↗

PubMed2001

Diabetic complications are associated with liver enzyme activities in people with type 1 diabetes.

This study was performed to clarify if diabetic complications are associated with liver enzyme activities in type 1 diabetic outpatients. Elevated activities of serum aminotransferases are a common sign of liver disease and are observed more frequently among people with diabetes than in the general population. Many studies have shown an association between specific diabetic complications and disturbances in various tissues, such as diabetic nephropathy and cardiovascular diseases, but only limited data are available on the possible association between diabetic complications and liver function. We studied 28 patients with type 1 diabetes. Mean age was 43.4+/-9.5 (S.D.), and duration of diabetes 25.2+/-9.7. Limited joint mobility (LJM) was assessed by the Rosenbloom's method. Background and proliferative retinopathy, and peripheral symmetrical polyneuropathy were also assessed. Activities of alanine amino transferase (ALT), gamma-glutamyl transferase (GGT) and alkaline phosphatase (ALP) in serum were determined. The metabolic control of the diabetes was evaluated by the glycosylated haemoglobin A(1c) (HbA(1c)) level and lipid values were also measured. ALT activity was associated with LJM (P<0.01) and with neuropathy (P<0.01). Association between GGT activity and LJM (P<0.01) and neuropathy (P<0.01) were also found. GGT activity was also associated with the severity of retinopathy (P<0.01). None of these associations was explained by confounding effects of diabetes duration, age, body mass index (BMI), HbA(1c) or alcohol consumption. In conclusion, diabetic complications such as LJM, retinopathy and neuropathy are associated with liver enzyme activities independent of alcohol consumption, BMI and metabolic control of diabetes.

Adult↗

PubMed2001

Biochemical markers of type III and I collagen: association with retinopathy and neuropathy in type 1 diabetic subjects.

AIMS: Connective tissue alterations may contribute to the development of diabetic long-term complications in eyes, kidneys and peripheral nerves. Collagen deposition may be increased in micro- and macrovascular disease in diabetic subjects. We tested whether biochemical markers of type III and I collagen metabolism are associated with retinopathy and neuropathy in Type 1 diabetes. METHODS: A total of 28 patients, mean age 43.4 +/- 9.5 (sd) and duration of diabetes 25.2 +/- 9.7 years, were studied. Stereoscopic colour fundus photographs were taken for assessment of retinopathy which was classified as no, background or proliferative. Concentrations of aminoterminal propeptide of type III procollagen (PIIINP), carboxyterminal propeptide of type I procollagen (PICP) and carboxyterminal cross-linked telopeptide of type I collagen (ICTP) in serum and urinary excretion of cross-linked N-telopeptides of type I collagen (NTX) and deoxypyridinoline crosslinks (DPyr) into urine were measured. RESULTS: Average serum PIIINP was higher in subjects with proliferative (3.2 +/- 1.1 microg/l) than without proliferative retinopathy (2.5 +/- 0.6 microg/l) (P = 0.03). Average serum PICP was higher in subjects without retinopathy (181.7 +/- 19.5 microg/l) than in subjects with background retinopathy (132.1 +/- 42.7 microg/l) (P = 0.02). Concentrations of other collagen markers were not different in subjects with or without retinopathy. No association between collagen markers and neuropathy was found. CONCLUSIONS: The increased synthesis of type III collagen, reflecting deposition of matrix and basement membrane connective tissue, may be involved in the pathogenesis of proliferative retinopathy in Type 1 diabetic subjects. On the other hand, we observed decreased synthesis of Type I collagen, which can result in weakened vascular integrity in subjects with retinopathy.

Adult↗

PubMed2000

Two loci on chromosomes 2 and X for premature coronary heart disease identified in early- and late-settlement populations of Finland.

Coronary heart disease (CHD) is a complex disorder constituting a major health problem in Western societies. To assess the genetic background of CHD, we performed a genomewide linkage scan in two study samples from the genetically isolated population of Finland. An initial study sample consisted of family material from the northeastern part of Finland, settled by a small number of founders approximately 300 years ago. A second study sample originated from the southwestern region of Finland, settled approximately 2,000 years ago. Families were ascertained through probands exhibiting premature CHD, defined as >50% stenosis of at least two coronary arteries at a young age, as verified by coronary angiography. Both study samples and the pooled data set provided evidence for linkage in two chromosomal regions. A region on chromosome 2q21.1-22 yielded two-point LOD scores of 3.2, 1.9, and 3.7, in the affected sib-pair (ASP) analyses of the northeastern, southwestern, and pooled study samples. The corresponding multipoint maximum-likelihood scores (MLSs) for these three study samples were 2.4, 1.3, and 3.0. In addition, a region on chromosome Xq23-26 resulted in two-point LOD scores of 1.9, 3.5, and 2.9 and in multipoint MLSs of 3.4, 3.1, and 2.5, respectively. In conclusion, this study identifies two loci likely to contribute to premature CHD: one on chromosome 2q21.1-22 and another on chromosome Xq23-26.

Age of Onset↗

PubMed2000

Comparison of autonomic withdrawal in men with obstructive sleep apnea syndrome, systemic hypertension, and neither condition.

Obstructive sleep apnea syndrome is characterized by obesity, nocturnal breathing abnormalities, arterial hypertension, and an increased number of cardiovascular events. Sympathetic activity is increased during nocturnal apneic episodes, which may mediate the cardiovascular complications of sleep apnea. We studied 15 male subjects with obstructive sleep apnea syndrome and associated hypertension, 54 subjects with mild to moderate essential hypertension, and 25 healthy normotensive men. Cardiovascular autonomic control was assessed using frequency domain measures of heart rate variability (HRV) during a controlled breathing test and during orthostatic maneuver. Compared with normotensive and hypertensive groups, total power and low- and high-frequency components of HRV during controlled breathing were significantly (analysis of variance, p<0.0001) lower in the obstructive sleep apnea syndrome. During the orthostatic maneuver, the change in total power of HRV was different between the 3 groups (analysis of variance, p = 0.004). The total power of HRV tended to increase in the normotensive (4.11+/-12.29 ms2) and in hypertensive (2.31+/-12.65 ms2) groups, but decreased (1.13+/-1.23 ms2) in the hypertensive group with obstructive sleep apnea syndrome. According to multivariate regression analysis, age and sleep apnea were the major independent determinants of HRV. This study found that an abnormal response to autonomic nervous tests characterizes hypertension in overweight subjects with obstructive sleep apnea syndrome. This could be due to autonomic withdrawal or supersaturation of the end-organ receptors by excessive and prolonged sympathetic stimulation. Our results also show the reduced response of orthostatic maneuver and controlled breathing in the hypertensive group compared with the normotensive group.

Autonomic Nervous System↗

PubMed2000

Increased arterial intima-media thickness and in vivo LDL oxidation in young men with borderline hypertension.

We used borderline hypertension as a model for prehypertension to examine the early influences of elevated blood pressure on subclinical atherosclerosis, lipoprotein oxidation, and cardiac adaptation. Healthy men (age 37+/-4 years) were classified prospectively into 2 groups on the basis of having either borderline hypertension (systolic 130 to 140 mm Hg or diastolic 85 to 89 mm Hg, n=16) or normal (<130/85 mm Hg, n=22) blood pressure values during the previous 2 years. The groups were matched for age, body size, and serum cholesterol levels. High-resolution ultrasound was used to measure intima-media thickness (IMT) of the carotid and brachial arteries, cardiac dimensions, and brachial artery endothelial function. Baseline low-density lipoprotein (LDL)-diene conjugation was measured as an estimate of in vivo LDL oxidation (ox-LDL). Compared with normotensive controls, men with borderline hypertension had higher IMT of the carotid artery (0.58+/-0.06 versus 0.75+/-0.07 mm, P<0.001) and IMT of the brachial artery (0.45+/-0.05 versus 0.57+/-0.07 mm, P<0.001), and increased levels of ox-LDL (29+/-9 versus 47+/-17 mol/L, P<0.001), but similar endothelial function. Left ventricular mass was similar in both groups, but there were significant differences in left ventricular geometry. In multivariate analyses, the predictors of carotid IMT were 24-hour systolic blood pressure (P<0.001) and ox-LDL (P=0.10). The current study demonstrates evidence of increased subclinical atherosclerosis and ox-LDL in borderline hypertension. These results are consistent with the idea that enhanced ox-LDL may be one of the pathophysiological events related to development of atherosclerosis in men with borderline elevated blood pressure.

Adult↗

PubMed2000

Cardiovascular risk factors of young adults in relation to parental socioeconomic status: the Cardiovascular Risk in Young Finns Study.

The socioeconomic status (SES) of the family influences the cardiovascular risk status of children and adolescents; however, it is not as well known whether parental SES has any effect on the risk factor profile of young adults. The aim of the present study was to investigate the relations of different aspects of parental SES, namely occupation, education, income and living area, to the common cardiovascular risk factors of their offspring (n = 919) aged 18, 21 and 24 years as a part of the Cardiovascular Risk in Young Finns Study in 1986. Subjects from farming families and rural areas had the highest serum total and low-density lipoprotein cholesterol values, and the lowest diastolic blood pressure compared with subjects from other occupational groups and subjects from urban regions. The diet of young adults from farming families and from rural areas contained more saturated fatty acids and less monounsaturated and polyunsaturated fatty acids. In addition, the body mass index was lower in subjects from urban regions compared with rural regions, and physical inactivity was less common in the urban group. Subjects with the highest parental occupational status smoked less compared with those with the lowest status. Parental education related inversely to physical inactivity and directly to dietary polyunsaturated fatty acids. The income level of the family associated positively with frequent inebriation by alcoholic beverages and inversely with the percentage of dietary energy from fat. In conclusion, there were modest inverse associations between different indicators of the SES of parents and some of the traditional risk factors of their offspring in young adulthood, which may contribute to the future risk of cardiovascular diseases.

Adolescent↗

PubMed1999

Constantly low HDL-cholesterol concentration relates to endothelial dysfunction and increased in vivo LDL-oxidation in healthy young men.

To test the hypothesis that low HDL-C concentration interferes with vascular endothelial function and lipoprotein oxidation, we measured endothelium-dependent flow mediated dilatation (FMD, %) of the brachial artery in young men (n=20) classified prospectively into two groups on basis of having either low or high HDL-C concentration over the past 2 years. As an estimate of in vivo low-density lipoprotein oxidation (ox-LDL), we measured LDL diene conjugation. FMD was present in the group with high HDL-C concentration, but impaired in the group with low HDL-C (5.5+/-3.2 vs 0.2+/-1.2%, P<0. 001). The group with high HDL-C level had significantly lower levels of ox-LDL compared to low HDL-C group (18.0+/-1.8 vs 22.9+/-4.4, P</=0.01). In all subjects, FMD correlated with HDL-C (r=0.59, P=0. 006), HDL(2)-C (r=0.62, P=0.004) and ox-LDL (r=-0.56, P=0.013) but not with HDL(3)-C (r=0.16, P=0.52). We conclude that constantly low HDL-C concentration is related with endothelial dysfunction and increased oxidative stress in healthy young men, consistent with the idea that HDL particles may protect endothelium and inhibit the oxidation of LDL. These findings may offer insight into increased atherosclerosis associated with low HDL-C levels.

Adult↗

PubMed1999

Importance of storing emergency serum samples for uncovering murder with insulin.

A case of a previously healthy 48-year-old man murdered by exogenous insulin administration is reported. The patient was delivered unconscious to the emergency unit. Initially, treatment with hyperbaric oxygen was commenced because decompression sickness was suspected. However, the treatment was aborted as the patient was found to be hypoglycaemic (nadir serum glucose 0.3 mmol/l) and treatment and diagnostics of hypoglycaemia commenced. Brain damage due to hypoglycaemia was severe, and the patient remained in a vegetative state for 2 months before he died of multiorgan failure. Serum samples drawn at admittance were stored frozen, whereby it was possible to show retrospectively, that while the concentration of insulin in serum was high (75 mU/l, increasing further to over 240 mU/l in the next few hours) concentration of C-peptide was low (below detection limit of 0.1 nmol/l) at the hypoglycaemic stage. It was concluded that the patient had received exogenous insulin somehow, and the police was informed. Circumstantial evidence obtained during ensuing criminal investigation was considered by the court to prove the patient's wife (a nurse) guilty of murder. The availability of stored frozen serum samples drawn at the early stage of hospitalization helped to uncover the crime involved in our case.

Blood Glucose↗

PubMed1999

The effect of four different antihypertensive medications on cardiovascular regulation in hypertensive sleep apneic patients--assessment by spectral analysis of heart rate and blood pressure variability.

OBJECTIVE: To study the effect of antihypertensive medications on autonomic nervous system in patients with hypertension and sleep apnea syndrome using frequency domain measures of heart rate and blood pressure variabilities. METHODS: The beta-receptor blocking agent atenolol (50 mg), the calcium antagonist isradipine SRO (2.5 mg), the diuretic hydrochlorothiazide (25 mg) and the ACE inhibitor spirapril (6 mg) once daily were given in a double-blind crossover schedule for 8 weeks. Cardiovascular autonomic control was assessed using frequency domain measures of heart rate variability during the spontaneous and controlled breathing tests. During orthostatic maneuver and cold pressor test the blood pressure variability analysis also was performed. RESULTS: In general, the responses of heart rate and blood pressure variabilities were abnormal in the patients with arterial hypertension and sleep apnea syndrome compared to reference data. Of the four drugs, only atenolol effected heart rate and blood pressure variabilities as it shifted the autonomic regulation to the vagal direction. Other antihypertensive drugs did not change any parameter of heart rate or blood pressure variabilities. CONCLUSION: The short-term treatment with atenolol in patients with arterial hypertension and sleep apnea syndrome is associated with normalization of autonomic nervous control judged by heart rate and blood pressure variability. Thus, beta-receptor blockade may have adjunctive beneficial effects beyond blood pressure reduction in these patients. However, the long-term effects of blood pressure reduction on autonomic nervous control remain to be studied.

Adrenergic beta-Antagonists↗

PubMed1999

HMG CoA reductase inhibitors are related to improved systemic endothelial function in coronary artery disease.

Inhibitors of 3-hydroxy-3-methylglutaryl coenzyme A (HMG CoA) reductase (statins) may enhance vascular endothelial function independent of their cholesterol lowering effect. To test this hypothesis, we surveyed two groups of patients (age 55+/-7, mean+/-SD) with coronary artery disease that were matched for age, blood pressure and serum lipid levels. Group 1 comprised 23 men without lipid-lowering medication and Group 2 included 22 patients with ongoing HMG CoA reductase inhibitor medication. Flow-mediated (endothelium-dependent) arterial dilatation (FMD) and nitrate-mediated (smooth muscle dependent) dilatation (NMD) were measured in the brachial artery using high resolution ultrasound. FMD was considerably higher in group 2 (4.3+/-2.6 vs. 2.6+/-2.8%; P<0.05). In multivariate regression model, statin use was the only significant (P<0.05) predictor of FMD. In all subjects, FMD correlated with statin dose (P<0.05 for trend). NMD was non-significantly higher in group 2 (11.4+/-5.0 vs. 9.0+/-4.2%, P=0. 08). We conclude that patients with established coronary artery disease on HMG CoA reductase inhibitor therapy have better vascular endothelial function than similar patients without the medication. These data provide further support for the idea that HMG CoA reductase inhibitors enhance endothelial function independent of their lipid-lowering effects. This may suggest that these drugs could be beneficial in secondary prevention of coronary artery disease regardless of the serum cholesterol concentration.

Adult↗

PubMed1999

Reproducibility of abnormal heart rate variability indices: the case of hypertensive sleep apnoea syndrome.

Before heart rate variability can be used as an investigational tool in the clinical setting, its reproducibility must be known. We studied heart rate variability four times during 44 weeks in 15 hypertensive patients with sleep apnoea syndrome. Time and frequency domain analytical approaches were used during the spontaneous and controlled breathing tests, orthostatic manoeuvre and the cold pressor test. Alterations in resting heart rate were taken into account using the coefficient of component variance. In general, the response of heart rate variability was abnormal and variability was reduced in the hypertensive patients with sleep apnoea syndrome compared with reference data. Time domain measures of heart rate variability demonstrated generally better reproducibility over four recordings than frequency domain measures in these hypertensive patients with sleep apnoea syndrome. On the other hand, the reproducibility of frequency domain measures depended on the specific conditions: during orthostatic manoeuvre and cold pressor test the best reproducibility was found using normalized units. In the reference data set, there were no significant differences between the two heart rate variability recordings during any of the autonomic nervous function tests. In this follow-up study we found that simple procedures such as the controlled breathing test show good reproducibility. More complex tests such as the orthostatic manoeuvre require special attention in order to obtain acceptable reproducibility of heart rate variability measurements. Quantitatively minor changes in the variability indices when the overall variability is reduced exert major effects on the results. Therefore we suggest that reproducibility data obtained in healthy volunteers are not valid for the interpretation of data in patients with damaged cardiovascular autonomic control.

Adult↗

PubMed1999

Associations of education with cardiovascular risk factors in young adults: the Cardiovascular Risk in Young Finns Study.

BACKGROUND: Low educational level is associated with an increased risk of coronary heart disease. The aim of the present study was to examine the relationships between education and common cardiovascular risk factors in young adults. METHODS: Trends in conventional risk factors of young adults aged 21, 24, 27 and 30 years in 1992 (n = 443) were examined across the educational groups as part of a 12-year follow-up study, the Cardiovascular Risk in Young Finns Study. Education was determined as participants' own educational level and as parental years of schooling. RESULTS: In males, subject's own education was related inversely and independently of parental school years to serum total and low density lipoprotein (LDL) cholesterol concentration, smoking and body mass index. In females, participant's own educational level associated inversely with smoking and physical inactivity. Parental school years was associated inversely and independently of one's own educational level with serum total and LDL cholesterol values and waist-hip ratio in females. In both genders, parental education was a stronger determinant of diet (butter use) than one's own educational level. CONCLUSIONS: The least educated young adults have adopted a more adverse lifestyle than the more educated. The risk factor profile in young adulthood, especially in females, is still affected by parental education. The influences of one's own and parental educational level on vascular risk profile should be taken into consideration when planning public health campaigns among young adults.

Adolescent↗

PubMed1999

Large-artery elastic properties in young men : relationships to serum lipoproteins and oxidized low-density lipoproteins.

Measures of arterial elasticity have been proposed as surrogate markers for asymptomatic atherosclerosis. We investigated the relations of serum lipoproteins, oxidized low-density lipoprotein (ox-LDL), and familial hypercholesterolemia (FH) to arterial elasticity among young men. As a marker of arterial elasticity we measured compliance in the thoracic aorta by using magnetic resonance imaging and in the common carotid artery by using ultrasound. LDL diene conjugation was used as a marker of ox-LDL. In study I, 25 healthy men (aged 29 to 39) were classified into 2 extreme groups according to previously measured high-density lipoprotein cholesterol to total cholesterol ratio (HDL-C/TC ratio). In study II, the healthy men were used as controls for 10 age matched asymptomatic patients with FH. In healthy men, the group with low HDL-C/TC ratio had decreased carotid artery compliance (2. 3+/-0.4% versus 1.9+/-0.5%/10 mm Hg, P=0.034). In univariate analysis, the compliance of the carotid artery associated with ox-LDL (r =-0.49, P=0.016) and HDL-C/TC ratio (r=0.41, P=0.040). In multivariate regression analyses, ox-LDL was the only independent determinant for compliance of the carotid artery (P=0.016). Aortic elasticity was not related to standard lipid variables, but the compliance of the ascending aorta associated with ox-LDL (r=-0.44, P=0.030). In FH patients, arterial elasticity was similar to that in controls. We conclude that elasticity of the common carotid artery is affected by serum lipid profile in young men. The current study demonstrates for the first time an in vivo association between ox-LDL and arterial elasticity suggesting that oxidative modification of LDL may play a role in the alteration of arterial wall elastic properties.

Adult↗

PubMed1998

Linkage of familial combined hyperlipidaemia to chromosome 1q21-q23.

More than half of the patients with angiographically confirmed premature coronary heart disease (CHD) have a familial lipoprotein disorder. Familial combined hyperlipidaemia (FCHL) represents the most common genetic dyslipidemia with a prevalence of 1.0-2.0%. FCHL is estimated to cause 10-20% of premature CHD and is characterized by elevated levels of cholesterol, triglycerides, or both. Attempts to characterize genes predisposing to FCHL have been hampered by its equivocal phenotype definition, unknown mode of inheritance and genetic heterogeneity. In order to minimize genetic heterogeneity, we chose 31 extended FCHL families from the isolated Finnish population that fulfilled strictly defined criteria for the phenotype status. We performed linkage analyses with markers from ten chromosomal regions that contain lipid-metabolism candidate genes. One marker, D1S104, adjacent to the apolipoprotein A-II (APOA2) gene on chromosome 1, revealed a lod score of Z = 3.50 assuming a dominant mode of inheritance. Multipoint analysis combining information from D1S104 and the neighbouring marker D1S1677 resulted in a lod score of 5.93. Physical positioning of known genes in the area (APOA2 and three selectin genes) outside the linked region suggests a novel locus for FCHL on 1q21-q23. A second paper in this issue (Castellani et al.) reports the identification of a mouse combined hyperlipidaemia locus in the syntenic region of the mouse genome, thus further implicating a gene in this region in the aetiology of FCHL.

Adult↗

PubMed1998

Glucose intolerance in familial combined hyperlipidaemia. EUFAM study group.

BACKGROUND: Familial combined hyperlipidaemia (FCHL) is a common hereditary disorder. Hypertriglyceridaemia is associated with glucose intolerance and insulin resistance. METHODS: To study glucose tolerance in FCHL patients with different lipid phenotypes [hypercholesterolaemia (IIA), mixed hyperlipidaemia (IIB), hypertriglyceridaemia (IV)], we investigated 253 family members and 92 spouses arising from 33 well-defined Finnish FCHL pedigrees. RESULTS: In oral glucose tolerance tests the affected family members had higher values for glucose area under the curve than did non-affected family members [673+/-127 min mmolL(-1), 754+/-145 min mmol L(-1), 846+/-180 min mmol L(-1) and 838+/-183 min mmol L(-1) for phenotypes normal, IIA, IIB and IV respectively; P < 0.001 after adjustment for body mass index, waist circumference and age]. Impaired glucose tolerance and diabetes were more common among affected than non-affected family members (prevalences of normal glucose tolerance 94.0%, 80.0%, 54.3% and 58.5% for phenotypes normal, IIA, IIB and IV). CONCLUSION: Affected FCHL family members were more glucose intolerant than non-affected family members. In men, this disturbance was not related to lipid phenotype nor was it explained by obesity.

Adolescent↗

PubMed1998

Coronary flow reserve is reduced in young men with IDDM.

Disturbances of coronary circulation have been reported in diabetic patients with microvascular complications but without obstructive coronary atherosclerosis. The aim of the present study was to investigate coronary flow reserve in young adult patients with IDDM but without microalbuminuria and diabetic autonomic neuropathy. Coronary flow reserve was determined in 12 nonsmoking male patients with IDDM (age 30.0 +/- 6.6 years) and 12 healthy matched volunteers. Groups were similar with respect to blood pressure and serum lipid concentrations, and no subject had a positive family history of coronary heart disease. The patients with IDDM had normal exercise echocardiography and autonomic nervous function tests. Five patients had minimal background retinopathy, and none had microalbuminuria. Positron emission tomography and [15O]H2O were used to measure myocardial blood flow at rest and after dipyridamole administration. The studies were performed during euglycemic hyperinsulinemia (serum insulin approximately 70 mU/l). The baseline myocardial blood flow was similar in patients with IDDM and in control subjects (0.84 +/- 0.18 vs. 0.88 +/- 0.25 ml x g(-1) x min(-1), NS). The myocardial blood flow during hyperemia was 29% lower in patients with IDDM (3.17 +/- 1.57) compared with the control subjects (4.45 +/- 1.37 ml x g(-1) x min(-1), P < 0.05). Consequently, coronary flow reserve (the ratio of flow during hyperemia and at rest) was lower in diabetic patients than in control subjects (3.76 +/- 1.69 vs. 5.31 +/- 1.86, P < 0.05) and the total coronary resistance during hyperemia was higher in diabetic patients (53.7 +/- 31.5) compared with the control subjects (31.4 +/- 11.6 mmHg x min x g x ml(-1), P < 0.05). The coronary flow reserve was similar in diabetic patients with and without mild background retinopathy. No association was found between the coronary flow reserve and serum lipid or HbA1c values in either group. Coronary flow reserve is impaired in young adult males with IDDM and no or minimal microvascular complications and without any evidence of coronary heart disease. This abnormality cannot be explained by standard coronary heart disease risk factors. The results imply early impairment of coronary vascular reactivity in IDDM patients, which may represent an early precursor of future coronary heart disease or may contribute to the pathogenesis of diabetic cardiomyopathy.

Adult↗

PubMed1997

Trends in serum lipid levels during 1980-1992 in children and young adults. The Cardiovascular Risk in Young Finns Study.

To assess secular trends in serum lipid levels in Finnish children and young adults, the authors examined a total of 3,517, 2,769, 2,392, 352, and 880 subjects who had complete data on serum lipids in 1980, 1983, 1986, 1989, and 1992, respectively, in a longitudinal follow-up study. Trend analyses were carried out among subjects aged 15 (n = 1,835) or 18 (n = 1,562) years to exclude the confounding effect of age on the study variables. Data on obesity, physical activity, smoking, and alcohol use were available from each study year, and data on diet were available for the study years 1980, 1986, and 1992. Between 1980 and 1992, mean total cholesterol levels decreased from 4.88 to 4.47 mmol/liter (from 189 to 173 mg/dl), and low density lipoprotein cholesterol levels decreased from 3.06 to 2.85 mmol/liter (from 119 to 110 mg/dl). The mean high density lipoprotein cholesterol levels decreased by 19%, from 1.43 to 1.15 mmol/liter (55.2 to 44.6 mg/dl). During 1986-1992, triglyceride levels increased by 15%, from 0.88 to 1.01 mmol/liter (78.2 to 89.9 mg/dl). During 1980-1992, body mass index values increased from 20.8 to 21.8 kg/m2, parallel to increases in skinfold thickness. In the diet, the ratio of polyunsaturated to saturated fatty acids increased from 0.26 to 0.39. Alcohol and oral contraceptive use became more frequent, and the subjects tended to become less physically active. In conclusion, a change in the lipid profile in Finnish adolescents aged 15 and 18 years and young adults during 1980-1992 was observed, characterized by a decrease in low density lipoprotein cholesterol and high density lipoprotein cholesterol levels and an increase in triglyceride level. Possible determinants for these changes include alterations in diet and a trend toward increased obesity.

Adolescent↗