Hypertension and overweight associated with hyperinsulinaemia and glucose tolerance: a longitudinal study of the Finnish and Dutch cohorts of the Seven Countries Study

Prevalence and determinants of hypertension among older adults: A comparative analysis of the 6th and 8th national health surveys of Bangladesh

BACKGROUND

Hypertension is a major public health concern in low-and middle-income countries. A nationwide Health, Population, and Nutrition Sector Development Program in Bangladesh has been shown to be effective in resource-poor settings. This article aims to investigate whether the prevalence and determinants of adult hypertension changed from 2011 to 2018.

METHODS

The determinants of adult hypertension were assessed in 2011 and 2018 data of Bangladesh Demographic and Health surveys. These two surveys included both men and women over the age of 34 years and measured their blood pressure, weight, height, and other covariates. For both surveys, we estimated the age-standard prevalence of hypertension and relative, attributable and mediated risk of determinants of hypertension using hierarchical mixed-effects sequential Poisson regression models.

RESULTS

The prevalence of adult hypertension increased by 10.9% from 29.5% in 2011 to 40.4% in 2018. The nationwide awareness program on the Health, Population and Nutrition Sector changed the risks associated with hypertension determinants over the years. During 2011, Socio-economic status (SES) was a major distal determinant of adult hypertension, explaining 21% of population-attributable risk (ART). However, other factors accounted for 90% of risk, mainly by excessive body weight (51%) and awareness of hypertension (39%). In contrast, SES only explained 16% of ART risk, with 97% of the risk mediated by excessive body weight (55%) and awareness of hypertension (41%).

CONCLUSION

The study results highlight that hypertension among older adult was significantly increased over the six-year period. Specially, the socio-economic status, awareness of hypertension and excessive body weight were the significant determinants. Being awareness of hypertension and excessive body weight changed the causal pathways of socio-economic status. The results also highlight the value of studying the effect of non-communicable disease awareness programs to enhance our comprehension of factors influencing health.

Metabolic syndrome; Definition, Pathogenesis, Elements, and the Effects of medicinal plants on it's elements

Introduction

Metabolic syndrome (MetS) is a cluster of metabolic risk factors that include central obesity, hypertension, insulin resistance, and atherogenic dyslipidemia and is strongly associated with a greater risk for developing cardiovascular disease and type 2 diabetes mellitus.

Methods

A literature search was conducted using the words metabolic syndrome, definition and pathogenesis in Scopus, and PubMed. The search also extended to cover medicinal plants and their role as a potential treatment of the metabolic syndrome. The search based on studies published in the English language from 1st of January 2000 to 30th of May 2021. The abstracts and the articles were then screened. Articles were scanned and read; further relevant references in the reference lists are also included.

Results

Both lifestyle factors and genetic factors are involved in the pathogenesis of the metabolic syndrome. Recently, MetS have gained significant attention due to the high prevalence of obesity worldwide. Diagnosis of patients with MetS is important to improve the outcomes of the disease by employing lifestyle and risk factors modifications. Currently, there is a rising interest in medicinal plants and their extracts because the medicinal plants have minimal side effects. Here we review the history, definitions, pathogenesis, management of metabolic syndrome and summarize the beneficial effects of some medicinal plants and their extracts on MetS.

Conclusion

Further research and clinical studies are needed to establish whether medicinal plants can be safely given as potential therapy for metabolic syndrome and whether this can be beneficial in low resources setting countries.

Paroxysmal Hypertension Induced by an Insulinoma

Insulinoma is a rare, usually benign, pancreatic neuroendocrine tumor. The clinical features of an insulinoma are fasting hypoglycemia with neuroglycopenic symptoms including confusion and unusual behavior, while hypertension is usually not associated with the disease. We herein report a patient with insulinoma who manifested paroxysmal hypertension and neuroglycopenic symptoms. The possible etiology of hypertension induced by an insulinoma is catecholamine release in response to hypoglycemia, which may cause acute hypertension through activation of the sympatho-adrenal system. This case implies that sustained hyperinsulinemia due to insulinoma can be functionally linked to the induction of paroxysmal hypertension.

Risk factors for hypertension in a population-based sample of postmenopausal women in Kolkata, West Bengal, India

Hypertension is a major public health problem worldwide. However, limited information is available regarding the risk factors for hypertension in postmenopausal women, particularly in urban populations in developing countries such as India. To investigate whether adiposity measures, serum lipids and lipoproteins as well as fasting plasma glucose can predict the risk of hypertension in a population based sample of postmenopausal women in Kolkata, India, we conducted a cross-sectional study of 415 postmenopausal women (aged 40 to 85), selected by cluster sampling from 12 wards of Kolkata. After multivariate adjustment, apolipoprotein B (apo B) and waist circumference (WC) showed the strongest association with hypertension. The risk of hypertension in the highest tertile compared with the lowest tertile was 2.57 (95% confidence interval = 1.00-6.61) for apo B and 2.55 (95% confidence interval = 1.07-6.06) for WC. Apo B and WC were the strongest risk factors for predicting hypertension among postmenopausal women in Kolkata.

An unusual cause of reversible axonal neuropathy and hypertension in a 10-year-old girl

A 10-year-old girl, who was referred with refractory epilepsy, had 1.5 years of episodic abnormal behavior. On examination, she also had hypertension and peripheral neuropathy. Hypoglycemia with correspondingly high insulin levels was documented during a confusional episode. MRI of the abdomen revealed an islet cell tumor in the body of the pancreas. One year after tumor excision, both the neuropathy and hypertension showed remarkable improvement. A final diagnosis of insulinoma with hypoglycemic axonal neuropathy and hypertension (reversed with tumor excision) was made. Insulinoma is the commonest cause of hyperinsulinemic hypoglycemia in adults, but is rare in childhood. To our knowledge, distal symmetrical motor-sensory axonal neuropathy has been described in only 40 patients, and hypertension has not been reported with insulinoma.

Matsuda-DeFronzo insulin sensitivity index is a better predictor than HOMA-IR of hypertension in Japanese: the Tanno-Sobetsu study

Here we examined whether the Matsuda-DeFronzo insulin sensitivity index (ISI-M) is more efficient than the homeostasis model assessment of insulin resistance (HOMA-IR) for assessing risk of hypertension. Cross-sectional and longitudinal analyses were conducted using normotensive subjects who were selected among 1399 subjects in the Tanno-Sobetsu cohort. In the cross-sectional analysis (n=740), blood pressure (BP) level was correlated with HOMA-IR and with ISI-M, but correlation coefficients indicate a tighter correlation with ISI-M. Multiple linear regression analysis adjusted by age, sex, body mass index (BMI) and serum triglyceride level (TG) showed contribution of ISI-M and fasting plasma glucose, but not of HOMA-IR. In the longitudinal analysis (n=607), 241 subjects (39.7%) developed hypertension during a 10-year follow-up period, and multiple logistic regression indicated that age, TG, systolic BP and ISI-M, but not HOMA-IR, were associated with development of hypertension. In subjects <60 years old, odds ratio of new-onset hypertension was higher in the low ISI-M group (ISI-M, less than the median) than in the high ISI-M group for any tertile of BMI. In conclusion, ISI-M is a better predictor of hypertension than is HOMA-IR. Non-hepatic IR may be a determinant, which is independent of TG, BP level and BMI, of the development of hypertension.

High blood pressure and obesity increase the risk of abnormal glucose tolerance in young adult african americans

Higher prevalence of both hypertension and obesity in African Americans is associated with a disproportionately greater burden of cardiovascular diseases in this ethnic group. The purpose of this study was to examine whether there is an interaction between hypertension and obesity that significantly increases the expression of metabolic risk factors for cardiovascular disease. Four groups of young adult African Americans were recruited based on their weight and blood pressure (BP). The effects of weight and BP on metabolic risk factors were analyzed based on data obtained from 484 patients. Results demonstrated that high BP and obesity were independently associated with increased odds of abnormal glucose tolerance, 1.8- and 2.2-fold, respectively. The coexistence of both high BP and obesity further increased the odds of abnormal glucose tolerance 4-fold. In addition, the geometric mean of homeostasis model assessment, an estimate of insulin resistance, increased by 18% with high BP, 60% with obesity, and 90% with the presence of both high BP and obesity. Although no statistically significant interaction between high BP and obesity was detected, the relationships of both high BP and obesity with metabolic risk factors were clearly additive.

Correlation of abdominal fat accumulation and stiffness of the abdominal aorta in obese children

AIM

To evaluate abdominal adipose tissue accumulation in obese children by ultrasound measurement and compare with the elastic properties of the abdominal aorta.

CHILDREN AND METHODS

A total of 56 obese children and a control group of 30 non-obese children had an ultrasound examination for measurements of thickness of visceral, preperitoneal, and subcutaneous fat as well as abdominal aorta stiffness parameters. Anthropometric measurements and metabolic risk profile were assessed by physical examination and blood tests.

RESULTS

Abdominal aorta stiffness parameters were all significantly higher in the obese children than in the controls. Among the adipose tissue compartments, visceral fat thickness was the strongest correlate of abdominal aorta stiffness parameters. Similarly, the correlation between visceral abdominal adipose tissue and fasting insulin levels, HOMA score, and pulse pressure also approached significance.

CONCLUSIONS

This study suggests that abdominal adipose tissue accumulation is closely associated with cardiovascular risk factors in obese children, and among abdominal adipose tissue compartments, visceral fat thickness was strongly correlated with the elastic properties of the abdominal aorta.

The association of intensity and overall level of physical activity energy expenditure with a marker of insulin resistance

AIMS/HYPOTHESIS

Physical activity is important in preventing insulin resistance, but it is unclear which dimension of activity confers this benefit. We examined the association of overall level and intensity of physical activity with fasting insulin level, a marker of insulin resistance.

METHODS

This was a cross-sectional analysis of the Medical Research Council Ely population-based cohort study (2000--2002). Physical activity energy expenditure (PAEE) in kJ kg(-1) min(-1) was measured by heart rate monitoring with individual calibration over a period of 4 days. The percentage of time spent above 1.5, 1.75 and 2 times resting heart rate (RHR) represented all light-to-vigorous, moderate-to-vigorous and vigorous activity, respectively.

RESULTS

Data from a total of 643 non-diabetic individuals (319 men, 324 women) aged 50 to 75 years were analysed. In multivariate linear regression analyses, adjusting for age, sex and body fat percentage, PAEE was significantly associated with fasting insulin (pmol/l) (beta = -0.875, p = 0.006). Time (% of total) spent above 1.75 x RHR and also time spent above 2 x RHR were both significantly associated with fasting insulin (beta = -0.0109, p = 0.007 and beta = -0.0365, p = 0.001 respectively), after adjusting for PAEE, age, sex and body fat percentage. Time spent above 1.5 x RHR was not significantly associated with fasting insulin in a similar model (beta = -0.0026, p = 0.137).

CONCLUSIONS/INTERPRETATION

The association between PAEE and fasting insulin level, a marker of insulin resistance, may be attributable to the time spent in moderate-to-vigorous and vigorous activity, but not to time spent in light-intensity physical activity.

Bosentan: a review of its use in pulmonary arterial hypertension and systemic sclerosis

Bosentan (Tracleer), an orally administered dual endothelin (ET)(A) and ET(B) receptor antagonist, is indicated in the treatment of pulmonary arterial hypertension (PAH). The efficacy of oral bosentan 125 mg twice daily in improving exercise capacity has been demonstrated in well designed trials in adult patients with idiopathic PAH or PAH associated with connective tissue disease or congenital systemic-to-pulmonary shunts, and in other trials in patients with idiopathic PAH or PAH associated with congenital heart disease or HIV infection. The beneficial effects of first-line bosentan treatment may be maintained for up to 1 year in patients with idiopathic PAH or PAH associated with connective tissue disease. Despite the potential for treatment-related teratogenicity and hepatotoxicity, long-term data indicate that bosentan is generally well tolerated at the approved dosages. Although well designed trials are required to establish the efficacy of bosentan versus or in combination with other specific PAH therapies, especially sildenafil, the convenient oral administration and lack of serious injection-related adverse effects may render bosentan preferable to other PAH therapies. Preliminary data indicate that bosentan may be effective in pediatric PAH patients, although randomized trials are required. Furthermore, bosentan may be a useful option for the prevention of digital ulcer development in patients with systemic sclerosis. Thus, in accordance with current clinical guidelines, bosentan is a convenient, effective, and generally well tolerated agent for use in the first-line treatment of class III PAH or second-line treatment of class IV PAH.

Longitudinal analyses among overweight, insulin resistance, and cardiovascular risk factors in children

OBJECTIVE

It has been questioned whether insulin resistance or obesity is the central abnormality contributing to the cardiovascular risk factors dyslipidemia and hypertension in obesity.

RESEARCH METHODS AND PROCEDURES

We studied weight status [SD score (SDS)-BMI], lipids (triglycerides, low-density lipoprotein- and high-density lipoprotein-cholesterol), blood pressure, and insulin resistance index [as homeostasis model assessment (HOMA) model] over a 1-year period in 229 obese white children (median age 12 years).

RESULTS

Any degree of decrease in HOMA was associated with significant decreases in triglycerides (p < 0.001), systolic blood pressure (p < 0.001), and diastolic blood pressure (p < 0.001), whereas the children with different changes in HOMA did not differ significantly in their weight changes. Only the children in the highest quartile of weight reduction (decrease in SDS-BMI > 0.5) demonstrated a significant decrease in systolic blood pressure (p < 0.001), diastolic blood pressure (p < 0.001), and triglycerides (p = 0.012), and an increase in high-density lipoprotein-cholesterol (p = 0.023), whereas with a lower degree of weight loss, there were no significant changes in cardiovascular risk factors. In contrast with a lower degree of weight loss, a reduction of >0.5 SDS-BMI was associated with a significant decrease in HOMA (p < 0.001).

DISCUSSION

Because blood pressure and triglycerides decreased with any degree of decrease in HOMA, independently of changes in weight status, these findings support the hypothesis that insulin resistance is the central abnormality contributing to these cardiovascular risk factors. Therefore, improving insulin resistance seems more important than reducing overweight to prevent or treat hypertension and dyslipidemia in obese children.

A retrospective cohort study on obesity and hypertension risk among Korean adults

A retrospective cohort of adult Korean males and females was conducted to evaluate the influence of obesity on the development of hypertension and to determine the level of the body mass index at which the risk of hypertension significantly increases. The subjects of this study were 1,467 men and 944 women aged 20 to 75 yr who were normotensive at the time of their initial examinations from 1990 to 1991, who had a follow-up examination at least 1 yr after their initial examinations, or whose blood pressure status could be confirmed by reviewing their medical records until June 2000. During an average follow-up period of 6.2 yr, 234 new cases of hypertension were identified. An analysis using the Cox proportional hazards model showed that the risk of developing hypertension increased with increasing age, body mass index, and amount of daily alcohol consumption in men; and with increasing age and body mass index in women. Comparing men and women whose body mass indices were smaller than 23 kg/m(2), the relative risks of hyper-tension were 2.56 times greater in men and 3.17 times greater in women, whose body mass indices were greater than 27 kg/m(2). Our study confirmed that obesity is a strong risk factor for hypertension among Korean adults. In addition, high alcohol consumption may be a significant risk factor for men.

Impaired glucose tolerance and impaired fasting glucose--a review of diagnosis, clinical implications and management

The diagnostic categories of impaired glucose tolerance (IGT) and impaired fasting glucose (IFG) were stablished in an effort to identify populations at risk for developing type 2 diabetes mellitus (T2DM). Both IGT and IFG are associated with increased risk of developing T2DM, but recent analyses found that the thresholds of risk vary among different populations and an even lower diagnostic threshold of IFG may be appropriate. IGT has been linked with an increased risk of cardiovascular events and some analyses have demonstrated an increased mortality risk compared with patients with normal glucose tolerance. In contrast, a continuum of increased risk of microvascular manifestations of T2DM has been demonstrated with IFG but an association of IFG with cardiovascular events has not been well established. Although both IGT and IFG are associated with resistance to insulin and increased insulin secretion, they do not identify the identical patient populations and are not equivalent in predicting development of T2DM or cardiovascular events. IFG and IGT have been associated with other features of insulin resistance, including dyslipidaemia, hypertension, abdominal obesity, microalbuminuria, endothelial dysfunction, and markers of inflammation and hypercoagulability, traits collectively referred to as the metabolic syndrome. Analyses of combinations of these components have also been associated with progression to T2DM, cardiovascular disease and increased mortality. The foundation of treatment for IGT, IFG, and the metabolic syndrome is lifestyle modification, including both dietary change and routine exercise. To date, several clinical trials have found that lifestyle modification is the most efficacious strategy to prevent progression to T2DM. Alternative treatments include pharmacotherapy with metformin or acarbose, both of which have been demonstrated to decrease the development of T2DM. Ongoing clinical trials are evaluating newer pharmacotherapies, including angiotensin converting enzyme inhibitors, angiotensin receptor antagonists, metglitinides and thiazolidinediones, to prevent both T2DM and cardiovascular events. In combination with lifestyle modification, these therapies offer hope for effective prevention of T2DM and its consequences in high-risk patients.

Hypertension and insulin disorders

Insulin resistance and/or compensatory hyperinsulinemia are associated with hypertension, obesity, dyslipidemia, and glucose intolerance. Insulin resistance and hyperinsulinemia are considered to increase blood pressure through sympathetic nervous system activation, renin-angiotensin system stimulation, and vascular smooth muscle cell proliferation. Leptin, magnesium ions, nitric oxide, endothelin, peroxisome proliferator-activated receptor gamma, and tumor necrosis factor-alpha also modulate blood pressure. Decreasing insulin resistance by lifestyle modification including diet, weight loss, and physical exercise has been shown to reduce blood pressure. Angiotensin-converting enzyme inhibitors have a beneficial effect on insulin resistance. On the other hand, the angiotensin II antagonist, losartan, does not affect insulin sensitivity. The selective alpha1-blockers have a favorable metabolic profile producing increases in insulin sensitivity. A short-acting type calcium channel blocker seems to decrease insulin sensitivity. On the other hand, long-acting type calcium channel blockers improve insulin sensitivity. Thiazide diuretics and most of the beta-blockers decrease insulin sensitivity. Vasodilatory beta-blockers have been reported to improve insulin sensitivity. Use of low-dose diuretics avoids the adverse effects seen with conventional doses.

Hypertension, insulin, and proinsulin in participants with impaired glucose tolerance

The association of insulin resistance and hyperinsulinemia to blood pressure has remained controversial. We examined the association of insulinemia to hypertension and blood pressure using baseline measurements for participants of the Diabetes Prevention Program (DPP). The DPP is a multicenter randomized controlled trial of 3819 participants with impaired glucose tolerance, and is designed to evaluate interventions for the delay or prevention of type 2 diabetes. The relationship between hypertension and insulinemia is described overall and by ethnicity. The effects of demographics (age and gender), adiposity, and glucose on the relationship are also presented. Asian Americans and African Americans had a similarly high prevalence of hypertension as did whites; American Indians had a lower prevalence of hypertension. Among participants not on antihypertensive medications, systolic blood pressure was significantly (but weakly) correlated with fasting insulin (r=0.12), homeostasis model assessment of insulin resistance (HOMA IR; r=0.13), and fasting proinsulin (r=0.10) when adjusted for age and gender (all, P<0.001). Systolic blood pressure showed similar correlations to fasting insulin in each ethnic group. After further adjustment for body mass index, the association of fasting insulin to systolic and diastolic blood pressures weakened considerably but remained significant (systolic: r=0.06, P=0.002; DBP: r=0.06, P<0.001). We conclude that a weak but significant association between insulin, (and proinsulin and HOMA IR) and blood pressure exists but is largely explained by overall adiposity. This association is similar among ethnicities, with the possible exception of Hispanics. The relation between insulin concentrations and blood pressure explains relatively little of the ethnic differences in hypertensive prevalence.

Hyperinsulinemia for the development of hypertension: data from the Hawaii-Los Angeles-Hiroshima Study

The present study was to assess the association of metabolic factors including hyperinsulinemia, with the development of hypertension in Japanese-Americans. One hundred forty normotensive (<140/90 mmHg) subjects aged 40 to 69 years old from the Hawaii-Los Angeles-Hiroshima study were followed for 15 years. Patients with cardiovascular disease were excluded. Body mass index (BMI), blood pressure (BP), serum total cholesterol (TC), triglycerides (TG), uric acid (UA), and glucose and insulin responses at baseline, 1 h, and 2 h after a glucose load were analyzed. Seventeen subjects became hypertensive (systolic BP > or = 160 mmHg, diastolic BP > or = 95 mmHg, or received drug treatment) during follow-up. Age- and sex-adjusted BMI, BP, serum UA, TG, insulin, and changes in fasting glucose during follow-up were higher in subjects who later became hypertensive than in those who did not. There was no difference in the change in BMI. Age- and sex-adjusted relative risks for the development of hypertension by quartiles of BMI, serum UA, TG, and the sum of insulin values (sigmainsulin) during a glucose load were highest in highest quartile of the distribution. When age, sex, systolic BP, BMI, serum UA, TC, TG, fasting glucose, sigmainsulin, and the change in BMI were used in a proportional hazard analysis, hyperinsulinemia, hyperuricemia, and systolic BP were found to be significant risk factors for hypertension. In conclusion, hyperinsulinemia, as well as obesity, hyperuricemia, and hypertriglyceridemia were associated with hypertension in Japanese-Americans. Hyperinsulinemia and hyperuricemia were independent predictors of the development of hypertension.

Antihypertensive drugs as predictors of type 2 diabetes among subjects with impaired glucose tolerance

AIMS

to examine the incidence rate of progression to Type 2 diabetes and baseline prognostic risk factors, focusing on hypertension and antihypertensive medication, in a cohort (n=207) with impaired glucose tolerance (IGT).

METHODS

after 2 and 4.6 (1. 9-6.4) years new cases of diabetes were diagnosed by the oral glucose tolerance test (OGTT). Hypertension (BP 160/95 or antihypertensive medication) was included in multiple regression analyses to assess the effect of risk factors on the development of diabetes.

RESULTS

diabetes developed in 32 subjects (19%), an incidence of 41/1000 (95% CI 28-57/1000) person-years. In univariate analyses, progression to diabetes was associated with a high (>9.0 mmol/l) 2-h OGTT value (P=0.008), a high fasting insulin (>12.0 mU/l) level (P=0.000), a high triglyceride (>/=1.3 mmol/l) level (P=0.028), a high BMI (>/=28.0 kg/m(2)) (P=0.013) and hypertension (P=0.003). The risk for the development of diabetes was not increased in hypertensive subjects without antihypertensive medication compared with normotensive subjects (OR 0.8, 95% CI 0.3-2. 6). However, it was increased in subjects with on medication, especially diuretics alone or in combination with other drugs. Hypertensive subjects on diuretics had higher levels of fasting insulin and triglycerides and higher BMIs at baseline than normotensive subjects. After adjustment for 2-h OGTT, fasting insulin, triglycerides and BMI, the OR for diabetes was 7.7 (95% CI 2.1-28.2) in hypertensive subjects using diuretics alone or in combination with other drugs and 2.6 (95% CI 1.0-6.7) in those using other drugs compared with normotensive subjects. The OR of diabetes corresponding to a one-unit increase in the 2-h OGTT concentration was 2.5 (95% CI 1.6-4.0) in the whole cohort.

CONCLUSIONS

the rate of progression from IGT to Type 2 diabetes in this population was similar to that seen in other studies among Caucasian populations. The use of antihypertensive medication, especially diuretics, and a high 2-h OGTT level were significant predictors of subsequent deterioration to diabetes.

Beta-blocking agents in patients with insulin resistance: effects of vasodilating beta-blockers

Essential hypertension is--at least in many subjects--associated with a decrease in insulin sensitivity, while glycaemic control is (still) normal. It seems that in hypertensive patients, two major functions of insulin are impaired: there is insulin resistance of peripheral glucose uptake (primarily skeletal muscle) and insulin resistance of insulin-stimulated vasodilation. In view of some retrospective data and meta-analyses, which showed a less than expected reduction in coronary events (coronary paradox), the metabolic side effects of the antihypertensive treatment have received more attention. Many groups have shown that conventional antihypertensive treatment, both with beta-blockers and/or diuretics, decreases insulin sensitivity by various mechanisms. While low-dose diuretics seem to be free of these metabolic effects, there is no evidence for this in the beta-adrenergic blockers. However, recent metabolic studies evaluated the effects of vasodilating beta-blockers, such as dilevalol, carvedilol and celiprolol, on insulin sensitivity and the atherogenic risk factors. None of them decreased insulin sensitivity, as has been described for the beta-blockers with and without beta1 selectivity. This supports the idea that peripheral vascular resistance and peripheral blood flow play a central role in mediating the metabolic side effects of the beta-blocking agents, as the vasodilating action (either via beta2 stimulation or alpha1-blockade) seems to more than offset the detrimental effects of the blockade of beta (or beta1) receptors. Further studies are needed to elucidate the relevance of the radical scavenging properties of these agents and their connection to their metabolic effects. Therefore, the beneficial characteristics of these newer beta-adrenoreceptor blockers suggest that the vasodilating beta-blocking agents could be advantageous for hypertensive patients with insulin resistance or type 2 diabetes.

An indirect estimate of the incidence of non-insulin-dependent diabetes mellitus

Our goal was to estimate non-insulin-dependent diabetes mellitus incidence in the Netherlands in the absence of equivocal empirical data. Incidence can be expressed as a function of age, sex, prevalence, and mortality. We obtained prevalence data from a study that pooled existing prevalence estimates. We calculated diabetes-related mortality using relative risks on all-cause mortality. Sensitivity for the rate of excess mortality was determined using the 95% confidence intervals (95% CI) of the relative risks. The estimated incidence increases exponentially with age, with a doubling time of 10 years for men and 9 years for women. The rate increases from 8.1 per 10,000 (95% CI = 7.7-8.8) for men ages 40-44 years and 7.0 (95% CI = 6.8-8.0) for women to 79.7 per 10,000 (95% CI = 69.5-90.9) for men ages 75-79 years and 85.8 (95% CI = 80.6-91.0) for women. When empirical estimates of incidence are largely lacking, the methodology described offers a useful alternative, in particular for the assessment of potential intervention effects.

Blood pressure in relation to obesity, insulin and the hypothalamic-pituitary-adrenal axis in Swedish men

OBJECTIVE

Some studies have shown a clustering of obesity, insulin and hypertension. The present study was performed to further characterize these associations.

SUBJECTS AND METHODS

In a population of 51-year-old men (n=284), measurements of systolic and diastolic blood pressure were analyzed in relation to general obesity (body mass index) and central obesity (waist: hip circumference ratio and abdominal sagittal diameter), and to the fasting insulin and insulin: glucose ratio as an approximation of insulin sensitivity. The regulation of diurnal cortisol secretion was examined in repeated salivary samples.

RESULTS

Linear regression analysis showed that all three parameters of obesity were significantly and strongly related to both systolic and diastolic blood pressure, more powerfully than insulin, glucose and insulin sensitivity (insulin: glucose ratio). Stepwise multiple regression showed that only central obesity, measured as the abdominal sagittal diameter, remained significantly (P< 0.001), and independently of insulin and insulin sensitivity, associated with both systolic and diastolic blood pressure (beta=7.5 and 4.2, respectively). A diurnal cortisol curve with normal rhythm was associated with lower than average blood pressures (P< 0.001) but not with insulin levels or the heart rate. In contrast, a flattened diurnal cortisol curve, indicating perturbations in the activity of the hypothalamic-pituitary-adrenal axis, was directly related to blood pressures, heart rate and insulin (P<0.001), and has previously been found to be strongly associated with abdominal obesity.

CONCLUSIONS

These findings suggest that general and central obesity is independently related to blood pressure, and that insulin may account for only part of this association. The activity of the hypothalamic-pituitary-adrenal axis is apparently important for blood pressure regulation, suggesting that mechanisms of the central nervous system have an impact.

High prevalence of abnormal glucose tolerance and metabolic disturbances in first degree relatives of NIDDM patients. A study in Catalonia, a mediterranean community

Our study aimed to analyse clinical and metabolic characteristics of first degree relatives of patients with non-insulin-dependent diabetes mellitus (NIDDM) in Catalonia. Two hundred and five subjects (39.8 +/- 14.2 year-old, 61% women) were included in the study. An oral glucose tolerance test (OGTT) was performed, obtaining basal plasma glucose and insulin, in order to calculate, %B (HOMA beta cell function) and %S (HOMA insulin sensitivity). A 30.7% of subjects showed an abnormal glucose tolerance, either as impaired glucose tolerance (IGT) (20.5%) or as NIDDM (10.2%). Glycaemia after the OGTT (120 min) was independently determined by fasting glycaemia and age (R2 = 0.50; P < 0.001). As expected, subjects with normal glucose tolerance (NGT) were significantly younger than IGT and NIDDM subjects. The relatives with IGT and NIDDM display more features of syndrome-X when compared to NGT. Likewise, NGT relatives were less insulin sensitive and their basal insulin levels were higher when compared with a control group of subjects without familial history of NIDDM (log %S, 3.6 +/- 0.4 vs. 3.9 +/- 0.4; P = 0.000; log-insulin 2.4 +/- 0.4 vs. 2.1 +/- 0.6 mU/l; P < 0.02). In comparison with the general population, of any age group, NIDDM and IGT were more common in those subjects with a family history of NIDDM. Interestingly, the rates, of abnormal glucose tolerance in the 55-64 and > 64 year groups in the general population were similar to those seen in relatives two decades younger. Our study not only confirms a high prevalence of impaired glucose tolerance (IGT and NIDDM) in subjects with a family history of NIDDM, but also that these abnormalities can be detected at a very early age. Globally, this piece of information corroborates that special attention and precocious detection programs should be addressed to relatives of NIDDM patients.

Epidemiology of non-insulin-dependent diabetes mellitus and its macrovascular complications. A basis for the development of cost-effective programs

Non-insulin-dependent diabetes mellitus is a major health problem in developed countries. The descriptive epidemiology of this disease and its cardiovascular complications are reviewed, and insulin resistance is identified as a common risk factor for both of them. The requirements for cost-effective programs to modify insulin resistance to prevent this disorder and its cardiovascular complications are discussed.