Lipodystrophy in patients with juvenile dermatomyositis--evaluation of clinical and metabolic abnormalities

OBJECTIVE

Lipodystrophy and associated metabolic abnormalities are being increasingly recognized as complications of juvenile dermatomyositis (JDM). We investigated the prevalence of lipodystrophy and the extent of metabolic abnormalities related to lipoatrophic diabetes mellitus in patients with JDM.

METHODS

Twenty patients with JDM were evaluated for evidence of lipodystrophy and associated lipoatrophic diabetes mellitus. All patients underwent clinical assessment, laboratory investigations, and metabolic studies (oral glucose tolerance test, lipid studies, insulin antibodies).

RESULTS

We found clinical evidence of lipodystrophy and lipoatrophic diabetes mellitus in 4 of 20 patients with JDM and metabolic abnormalities known to be associated with lipodystrophy in another 8 patients. The 20 patients with JDM were categorized as follows: Group 1 (Patients 1-4) consisted of patients with lipodystrophy and either diabetes mellitus (2 patients) or impaired glucose tolerance (2 patients); Group 2 (Patients 5-12): no lipodystrophy but abnormal glucose and/or lipid studies; Group 3 (Patients 13-20): no lipodystrophy and no abnormalities of glucose and lipid studies.

CONCLUSION

We found 25% of patients with JDM have lipodystrophy, and 50% present with hypertriglyceridemia and insulin resistance. Screening for metabolic abnormalities in JDM should be included in routine followup because of the effect of lipodystrophy on longterm prognosis.

Polynesians: prone to obesity and Type 2 diabetes mellitus but not hyperinsulinaemia

AIMS

To compare the extent of hyperinsulinaemia among New Zealand Europeans and Polynesians (an ethnic group at high risk of Type 2 diabetes mellitus).

METHODS

A cross-sectional survey from randomly selected households was conducted in inner urban South Auckland. Subjects were either European, Maori or Pacific Islands Polynesians aged 40-79 years and were screened for diabetes using a random blood glucose. Those with an elevated result, and 20% randomly selected from those with a normal screening result, were invited to a 75-g glucose tolerance test. WHO criteria (1998) for diabetes were used.

RESULTS

In those aged 40-59 years, total prevalence of diabetes was 7.5 (6.2-9.0)% in Europeans but 21.1 (16.6-25.6)% among Maori and 25.0 (19.8-30.1)% among Pacific peoples; obesity (body mass index >or= 31.0 kg/m2) was present in 26% Europeans, 63% Maori and 69% Pacific peoples. Non-diabetic Polynesians were relatively hyperglycaemic and hyperinsulinaemic. After adjusting for the degree of obesity, Polynesians had similar insulin levels to Europeans.

CONCLUSIONS

These findings indicate that Polynesians are not intrinsically insulin resistant as a group, a prerequisite found in most other ethnic groups at high risk of Type 2 diabetes mellitus. The high prevalence of Type 2 diabetes in Polynesians could be the result of their high prevalence of obesity.

Relationship of the metabolic syndrome and obesity to polycystic ovary syndrome: a controlled, population-based study

OBJECTIVE

Although hyperinsulinemia seems to be an essential feature of polycystic ovary syndrome, the frequency of gynecologic disorders related to polycystic ovary syndrome at a population level in women with evident metabolic syndrome is not known.

STUDY DESIGN

We conducted a cross-sectional, population-based study. Participants (N = 204) were recruited from a random sample of women in 5 age groups (range, 35-54 years) living in a defined area. Metabolic syndrome was considered to be present if 3 of the following 8 criteria were fulfilled: (1) first-degree relative with type II diabetes, (2) body mass index > or = 30 kg/m2, (3) waist/hip ratio > or = 0.88, (4) blood pressure > or = 160/95 mm Hg or drug treatment for hypertension, (5) fasting serum triglyceride level > or = 1.70 mmol/L, (6) high-density lipoprotein cholesterol value < 1.20 mmol/L, (7) abnormal glucose metabolism, and (8) fasting insulin value > or = 13.0 mU/L. The frequency of metabolic syndrome was 106 (19.5%) of 543 cases. The control group consisted of 62 overweight women without central obesity or metabolic syndrome and 53 healthy lean women (body mass index < 27 kg/m2.

RESULTS

The group with metabolic syndrome differed from the other women according to most of the selection criteria and also had the highest free testosterone concentration. However, there were no differences between the groups regarding parity, infertility problems, or obstetric outcome. However, oligomenorrhea appeared to be more common in women with metabolic syndrome, especially in those with more severe symptoms (46.2%), than in obese (25.4%) and lean (15.1%) control subjects. Polycystic-like ovaries were detected by vaginal ultrasonography with similar frequency (13.1%, 15.3%, and 13.2% in women with metabolic syndrome, obese women, and lean women, respectively).

CONCLUSIONS

Surprisingly few women with metabolic syndrome had symptoms suggestive of polycystic ovary syndrome, in comparison with obese and lean women. Our results suggest that at the population level polycystic ovary syndrome only accounts for a distinct subgroup of a much wider problem, metabolic syndrome.

Mutations in the small heterodimer partner gene are associated with mild obesity in Japanese subjects

Mutations in several genes encoding transcription factors of the hepatocyte nuclear factor (HNF) cascade are associated with maturity-onset diabetes of the young (MODY), a monogenic form of early-onset diabetes mellitus. The ability of the orphan nuclear receptor small heterodimer partner (SHP, NR0B2) to modulate the transcriptional activity of MODY1 protein, the nuclear receptor HNF-4alpha, suggested SHP as a candidate MODY gene. We screened 173 unrelated Japanese subjects with early-onset diabetes for mutations in this gene and found five different mutations (H53fsdel10, L98fsdel9insAC, R34X, A195S, and R213C) in 6 subjects as well as one apparent polymorphism (R216H), all present in the heterozygous state. Interestingly, all of the subjects with the mutations were mildly or moderately obese at onset of diabetes, and analysis of the lineages of these individuals indicated that the SHP mutations were associated with obesity rather than with diabetes. Therefore, an additional group of 101 unrelated nondiabetic subjects with early-onset obesity was screened for mutations in the SHP gene. Two of the previously observed mutations (R34X and A195S) and two additional mutations (R57W and G189E) were identified in 6 subjects, whereas no mutations were identified in 116 young nondiabetic lean controls (P = 0.0094). Functional studies of the mutant proteins show that the mutations result in the loss of SHP activity. These results suggest that genetic variation in the SHP gene contributes to increased body weight and reveal a pathway leading to this common metabolic disorder in Japanese.

Metabolic disorders in vertigo, tinnitus, and hearing loss

Vertigo, tinnitus, and hearing loss are common complaints among populations of industrial countries, especially in persons older than 40 years. Numerous agents are known to incite vertigo, tinnitus, and hearing loss, among them hyperinsulinemia, diabetes mellitus, and hyperlipidemia. In this study, we proposed to assess the occurrence of hyperinsulinemia, diabetes mellitus, and hyperlipidemia in patients suffering from vertigo, tinnitus, or hearing loss of unknown origin. Results of various tests in 48 patients were compared to those in 31 control subjects. Assessments of body mass index, blood pressure, and laryngological, audiometric, and electronystagmographic parameters were performed in all study participants. An oral glucose tolerance test was used to evaluate insulin levels, and lipoprotein phenotyping served to determine cholesterol, triglyceride, and lipoprotein levels. Patients were found to be significantly more overweight (on the basis of body mass index) than were the control subjects. Hypertension was more common among patients than controls, but the difference was significant only between the men in the two groups. Disturbances of glucose metabolism were found in 27.1% of patients but in only 9.7% of controls. Diabetes mellitus was not present in any controls but was identified in four patients. Hyperinsulinemia was almost twice as common in patients as in controls. Only the occurrence of hyperlipoproteinemia seemed not to differ between patients and control subjects. We conclude that such disturbances of glucose metabolism as diabetes mellitus and hyperinsulinemia may be responsible for inner ear diseases, whereas the role of disturbances of lipid metabolism remains vague.

Plasma insulin and all-cause, cardiovascular, and noncardiovascular mortality: the 22-year follow-up results of the Helsinki Policemen Study

OBJECTIVE

To investigate the association of plasma insulin with all-cause, cardiovascular, and noncardiovascular mortality.

RESEARCH DESIGN AND METHODS

We studied 22-year mortality data from the Helsinki Policemen Study The study population comprised 970 men, 34-64 years of age, who were free of coronary heart disease, other cardiovascular disease, and diabetes. Area under the insulin response curve (AUC insulin) during an oral glucose tolerance test was used to reflect plasma insulin levels.

RESULTS

During the follow-up period, 276 men died: 130 from cardiovascular and 146 from noncardiovascular causes. The hazard ratio (HR) for hyperinsulinemia (highest AUC insulin quintile vs. combined lower quintiles) with regard to all-cause mortality adjusting for age, was 1.94 (95% CI 1.20-3.13) during the first 10 years of the follow-up period and 1.51 (1.15-1.97) during the entire 22 years; adjusting for other risk factors, the HR was 1.88 (1.08-3.30) and 1.37 (1.00-1.87) during 10 and 22 years, respectively The corresponding HRs for cardiovascular mortality during 10 and 22 years were 2.67 (1.35-5.29) and 1.73 (1.19-2.53), respectively, for age-adjusted and 2.30 (1.03-5.12) and 1.39 (0.90-2.15), respectively, for multiple-adjusted HRs. A U-shaped association was observed between insulin and noncardiovascular mortality, multiple-adjusted HRs for lowest and highest versus middle AUC insulin quintiles were 1.85 (1.20-2.86) and 1.43 (0.91-2.24), respectively

CONCLUSIONS

Hyperinsulinemia was associated with increased all-cause and cardiovascular mortality in Helsinki policemen independent of other risk factors, although these associations weakened with the lengthening of the follow-up period. The association of insulin with noncardiovascular mortality was U-shaped.

Glucose and insulin abnormalities relate to functional capacity in patients with congestive heart failure

AIMS

In addition to diabetes mellitus, less severe abnormalities of glucose and insulin metabolism may be related to functional status in patients with heart failure. We examined the relationship of hyperglycaemia (> or =6.1 mmol. l(-1)) and hyperinsulinaemia (> or =11.2 mU. l(-1)) to functional status and cardiac function in patients with heart failure.

METHODS AND RESULTS

Fasting plasma glucose and insulin levels were obtained in 663 heart failure patients. The average left ventricular ejection fraction was 0.28+/-0.07, 63% were in New York Heart Association Functional Class (NYHA-FC) I/II and 37% were in NYHA-FC III/IV. Twenty seven percent had diabetes mellitus, but an additional 8% had undiagnosed diabetes mellitus (glucose > or =7 mmol. l(-1)) and 9% had glucose levels between 6.1 and 7 mmol. l(-1), so that a total of 43% (287) of patients had elevated glucose levels (> or =6.1 mmol. l(-1)). In general, more diabetic patients had NYHA-FC III/IV symptoms, shorter 6 min walk distances, but similar left ventricular ejection fractions compared to non-diabetic patients. The non-diabetic patients in NYHA-FC III/IV had higher glucose and insulin levels than patients in NYHA-FC I/II (6.3+/-0.2 vs 5.6+/-0.1 mmol. l(-1), P<0.001 and 19.6+/-2.3 vs 10. 2+/-0.6 mU. l(-1), P<0.001). Non-diabetic patients with elevated glucose levels had shorter 6 min walk distances compared to those with normal glucose levels (368.2+/-8 m vs 389.+/-4 m, P=0.02), however, left ventricular ejection fraction was similar.

CONCLUSION

Glucose abnormalities are extremely common in heart failure patients (43% of patients). Diabetes mellitus and hyperglycaemia or hyperlinsulinaemia in non-diabetic patients were related to worse symptomatic status but not worsening left ventricular ejection fraction compared to patients with normal glucose and insulin levels.

Hypertriglyceridemic waist: A marker of the atherogenic metabolic triad (hyperinsulinemia; hyperapolipoprotein B; small, dense LDL) in men?

BACKGROUND

The present study tested the hypothesis that simple variables, such as waist circumference and fasting plasma triglyceride (TG) concentrations, could be used as screening tools for the identification of men characterized by a metabolic triad of nontraditional risk factors (elevated insulin and apolipoprotein [apo] B and small, dense LDL particles).

METHODS AND RESULTS

Results of the metabolic study (study 1) conducted on 185 healthy men indicate that a large proportion (>80%) of men with waist circumference values >/=90 cm and with elevated TG levels (>/=2.0 mmol/L) were characterized by the atherogenic metabolic triad. Validation of the model in an angiographic study (study 2) on a sample of 287 men with and without coronary artery disease (CAD) revealed that only men with both elevated waist and TG levels were at increased risk of CAD (odds ratio of 3.6, P<0.03) compared with men with low waist and TG levels.

CONCLUSIONS

It is suggested that the simultaneous measurement and interpretation of waist circumference and fasting TG could be used as inexpensive screening tools to identify men characterized by the atherogenic metabolic triad (hyperinsulinemia, elevated apo B, small, dense LDL) and at high risk for CAD.

Hyperinsulinemia and abdominal obesity are more prevalent in non-diabetic subjects with family history of type 2 diabetes

BACKGROUND

This study was undertaken in order to identify the relationships between family history of type 2 diabetes and cardiovascular risk factors in non-diabetic Mexican individuals.

METHODS

The design was a cross-sectional, population-based study stratified by age and sex. Participants consisted of 189 non-diabetic volunteers 30-64 years of age, both males and non-pregnant females randomly selected from a middle income neighborhood in Durango, Mexico and distributed into two groups, with and without family history of type 2 diabetes mellitus. Hypertensive subjects were excluded. Body mass index (BMI) and waist-to-hip ratio (WHR) were assessed. Hematocrit, both fasting and 2-h post 75-g glucose load insulin, and glucose levels, lipid profile, serum albumin, and proteinuria were measured.

RESULTS

Ninety-four (49.7%) individuals with family history of type 2 diabetes, and 95 (50.3%) in the control group were included. The prevalence of obesity was greater among women with family history of diabetes, 39 (73.6%) vs. 27 (50.0%) of the control group, p = 0.02. Adiposity tended to be centrally distributed in 86 subjects, of whom 22 (25. 6%) males and 54 (62.8%) females were in the group with family history of diabetes and four (4.6%) males and six (7.0%) females in the control group, p <0.000. Multivariate logistic regression analysis showed a strong relationship between family history of type 2 diabetes with both abdominal obesity (odds ratio [OR] 4.2, CI 95% 1.9-10.1, p <0.05) and fasting hyperinsulinemia (OR 3.1, CI 95% 1. 4-11.2, p <0.05).

CONCLUSION

In the absence of additional risk factors such as diabetes and hypertension, there is a strong relationship between family history of diabetes with hyperinsulinemia and abdominal obesity in middle-aged Mexican individuals.

Abdominal adiposity and clustering of multiple metabolic syndrome in White, Black and Hispanic americans

PURPOSE

The aim of this study was to evaluate the association of abdominal adiposity assessed by waist circumference (WC) with clustering of multiple metabolic syndromes (MMS) in White, Black and Hispanic Americans. MMS was defined as the occurrence of two or more of either hypertension, type 2 diabetes mellitus, dyslipidemia, hypertriglyceridemia or hyperinsulinemia.

METHODS

The number of MMS and fasting insulin (a surrogate measure of MMS) were each used as dependent variables in gender-specific multiple linear regression models, adjusting for age, smoking and alcohol intake. The contribution of WC to interethnic differences in clustering of MMS and fasting insulin concentration was assessed in gender-specific linear regression models. The risk of MMS due to large waist was estimated by comparing odds ratio for men with WC >/= 102 cm with those with WC < 102, and women with WC >/= 88 cm with women with WC < 88 cm in the logistic regression model adjusting for age, smoking and alcohol intake.

RESULTS

WC was positively and independently associated with clustering of MMS and increased fasting insulin concentration adjusting for age, smoking and alcohol intake in the three ethnic groups (p < 0.01). Black ethnicity was associated with clustering of MMS and fasting insulin concentration (p < 0.01). Hispanic ethnicity was also associated with clustering of MMS in men and associated with fasting insulin concentration in both men and women (p < 0.01). In both men and women, the risk of MMS clustering was strongly associated with increased WC in all ethnic groups independent of BMI.

CONCLUSION

WC appears to be a marker for multiple metabolic syndromes in these ethnic groups. The results of this investigation lend support to the view that waist measurement should be considered as a clinical variable for assessing the risk of cardiovascular diseases.

Microalbuminuria in never-treated hypertensives: lack of relationship to hyperinsulinemia and genetic predisposition to hypertension

We evaluated the relationship of microalbuminuria to hyperinsulinemia and family history of hypertension in 92 never-treated essential hypertensives (mean 24-h blood pressure >140 or 90 mm Hg), with positive (F+) or negative (F-) family history of hypertension: 31 had microalbuminuria (MA+) (urinary albumin excretion [UAE], 30 to 300 mg/24 h) and 61 had normal (<30 mg/24 h) UAE (MA-). Glucose and insulin values before and 30, 60, 90, and 120 min after an oral glucose load were measured together with an index of peripheral insulin activity (10(4)/ insulin x glucose values at glucose peak). Subjects with and without microalbuminuria did not differ with regard to age, sex, body mass index, and 24-h heart rate, whereas 24-h, daytime, and nighttime systolic and diastolic blood pressure were significantly higher in MA+ than MA- patients. The prevalence of positive family history of hypertension was similar between MA+ and MA-, as were fasting and stimulated glucose and insulin values and the index of peripheral insulin activity. Subdividing the patients on the basis of family history of hypertension (59 F+, 33 F-) UAE was not significantly different between F+ and F-. UAE did not correlate with glucose and insulin parameters. From our results, in never-treated hypertensives, microalbuminuria is associated with higher blood pressure values, but is related neither to genetic predisposition to hypertension, nor to hyperinsulinemia; therefore, impaired insulin sensitivity and microalbuminuria are two components of the hypertensive syndrome, largely independent of each other.

Birth weight and the metabolic syndrome: thrifty phenotype or thrifty genotype?

BACKGROUND

Inverse correlations have been reported between birth weight and the Metabolic Syndrome (abdominal obesity, insulin resistance, hyperinsulinemia, glucose intolerance, dyslipidemia, and hypertension). These correlations are thought to reflect primarily nutritional inadequacies during fetal and early life. We explored familial influences on these correlations.

METHODS

Using birth weight data on 602 subjects from 65 pedigrees, we partitioned phenotypic correlations into familial and non-familial. The former are usually regarded as reflecting primarily genetic influences, although they may also reflect environmental influences that are shared by family members, and the latter reflect random environmental influences.

RESULTS

A consistent pattern of positive familial and inverse non-familial correlations were observed. The strongest familial correlations were between birth weight and fasting insulin (r = 0.58, p = 0.002), leptin (r = 0.48, p = 0.021), split proinsulin (r=0.51, p = 0.090), and heart rate (r = 0.39, p = 0.037). An inverse familial correlation was observed with HDL cholesterol (r = -0.28, p = 0.018). Non-familial correlations were weaker and only two-- subscapular-to-triceps skinfold ratio and fasting insulin--were statistically significant.

CONCLUSION

Since the familial and non-familial correlations were in opposite directions, we attribute the former to the pleiotropic effects of genes. Specifically, we conclude that genes that increase birth weight also worsen the Metabolic Syndrome in adult life. Since the inverse correlations reported in the literature reflect mainly cohorts born in the early part of the 20th century, improved maternal nutrition since then may have allowed the expression of genetic influences in our participants, all of whom were born after 1950.

Acanthosis nigricans, hyperinsulinaemia and risk factors for cardiovascular disease

We examined the association between acanthosis nigricans, hyperinsulinaemia and other risk factors for cardiovascular disease in patients from the United Arab Emirates. Height, weight and sitting blood pressure were recorded in 122 patients with acanthosis nigricans, and blood samples were obtained for measuring fasting cholesterol, high-density lipoprotein cholesterol, triglyceride and uric acid levels. In addition, a glucose tolerance test was performed and blood was sampled for insulin and glucose. Our results indicate that the patients with acanthosis nigricans had a high prevalence of abnormal glucose tolerance and hyperinsulinaemia. In addition, euglycaemic patients with hyperinsulinaemia had a cluster of risk factors for cardiovascular disease.

Risk stratification in hypertension: new insights from the Framingham Study

Five decades of epidemiologic research have established that blood pressure elevation is a common and powerful contributor to all of the major cardiovascular diseases, including coronary disease, stroke, peripheral artery disease, renal disease, and heart failure. The common variety of hypertension designated benign essential hypertension was not shown to be either benign or essential. Although clinicians favor the diagnosis and treatment of hypertension in terms of diastolic blood pressure elevation and categoric cut points, epidemiologic data show a more important influence of systolic blood pressure, and a continuous, graded influence of blood pressure even within what is regarded as the normotensive range. An important revelation in epidemiologic hypertension research is that hypertension usually occurs in conjunction with other metabolically linked risk factors; therefore, less than 20% occurs in isolation. The other risk factors that tend to accompany hypertension include glucose intolerance, obesity, left ventricular hypertrophy, and dislipidemia (elevated total, LDL, and small dense LDL cholesterol levels, raised triglyceride, and reduced HDL cholesterol levels). Clusters of three or more of these additional risk factors occur at four times the rate expected by chance. This clustering is attributed to an insulin resistance syndrome promoted by abdominal obesity. The amount of risk factor clustering accompanying elevated blood pressure was observed to increase with weight gain. Based on Framingham Study data the prevalence of insulin resistance syndrome in the general population could be as high as 22% in men and 27% in women. Risk of coronary disease, the most common and most lethal sequel to hypertension, increased stepwise with the extent of risk factor clustering. Among persons with hypertension, about 40% of coronary events in men and 68% in women are attributable to the presence of two or more additional risk factors. Only 14% of coronary events in hypertensive men and 5% of those in hypertensive women occurred in the absence of additional risk factors. Other important features of risk stratification of hypertension are the presence of an elevated heart rate and left ventricular hypertrophy, and an elevated fibrinogen that often accompany hypertension. Recent population-based data reported suggest that elevated renin accompanying hypertension may independently enhance the risk of coronary events. Because clustering of other major risk factors with hypertension is the rule, the prudent physician should routinely screen for the presence of these other factors. Multivariate risk assessment profiles are now available for coronary disease, stroke, peripheral artery disease, and heart failure, to enable physicians to pool all the relevant risk factor information so as to arrive at a composite risk estimate. Hypertensive patients are more appropriately targeted for therapy by such risk stratification and the goal of the therapy should be to improve the multivariate risk profile.

Osteoporosis in older adults with non-insulin-dependent diabetes mellitus: is it sex related?

OBJECTIVE

To assess the association of non-insulin-dependent diabetes mellitus (NIDDM) with bone mineral density (BMD) and its effect on bone turnover.

METHODS

BMD (measured by osteo C.T. of the lumbar spine) and bone resorption (deoxypyridinoline) and formation (alkaline phosphatase bone isoenzyme) markers were measured in 40 female postmenopausal patients with NIDDM and in 40 non-diabetic females of the same age. The same investigations were carried out in 20 males with NIDDM and in 20 normal non-diabetic males.

RESULTS

Women with diabetes had significantly (p < 0.01) higher BMD levels than women with normal glucose tolerance. Diabetic females were also significantly overweight (p < 0.001) and had a longer duration after menopause (p < 0.02). Bone resorption markers and bone formation markers were significantly (p < 0.001) higher in the control group compared with the diabetic group. Men with diabetes had BMD levels similar to those men with normal glucose tolerance. Also there was no significant difference on comparing bone resorption and formation markers in the group of diabetic men to the control male group.

CONCLUSION

Older women with NIDDM had better BMD than normal women. No difference in bone density by diabetic status were observed in men. That sex difference may be explained by the obesity and the greater androgenecity reported in women with hyperglycemic and hyperinsulinemic conditions.

What is the significance of macrosomia?

This commentary/review briefly considers the diverse criteria recommended for classification of overweight infants. Macrosomia continues to be a vexing problem for both obstetricians and pediatricians. Among the various techniques possible for use in assessing body composition, none are more practical than body weight relative to gestational age. The criteria for normative data from large populations are reviewed. The stringent definition, i.e., exceeding +2 SD of an appropriate normative population, is reaffirmed. Using these criteria, infants of diabetic mothers showed a significant relationship of body weight to fetal hyperinsulinemia.

Women relatives of Hispanic patients with type 2 diabetes are more prone to exhibit metabolic disturbances

Hyperinsulinemia and impaired insulin action are familial and predictive of Type 2 diabetes onset. Since high levels of insulin are characteristic of our general (venezuelan)hispanic population, the purpose of this investigation was to identify early metabolic defects in a group of healthy first degree relatives of Type 2 diabetic patients. We studied 46 (29 women and 17 men; ages ranging 18-66 y) first degree relatives of Type 2 diabetic patients comparing them with 22 (12 women and 10 men; ages ranging 22-60 y) subjects who had no family history of diabetes. All subjects underwent resting blood pressure and anthropometric measurements; a 75 g oral glucose tolerance test with determination of glucose and insulin and a fasting lipid profile. The relatives of Type 2 diabetic patients had higher tricipital (TC) and subscapular (SC) skinfolds, and elevated DBP in relation to the control group. The skinfolds elevation was more evident in women, while in men the elevation in DBP predominates. None of the relatives had glucose intolerance, however, the glucose-stimulated insulin response was elevated at all points in men as well as in women. No difference was observed in the HOMA values for IR and beta cell function, or in the delta I30/delta G30 ratio. The lipid profile showed a marked elevation in TG levels in men as well as in women, with low HDL-C values in men. No other lipid abnormalities were observed. Correlation analysis revealed strong association between BMI and WHR with skinfolds and several parameters of the carbohydrate metabolism in women, but not in men. IR in women was possitively associated with skinfolds, SBP and lipid parameters and beta cell function with VLDL-C. Adult relatives of Type 2 diabetic venezuelan patients from hispanic origin had, early in their lives, several parameters of the metabolic syndrome as hyperinsulinemia, obesity, dyslipidemia and high blood pressure. These alterations were more prominent in women, group in which the association among BMI, WHR and IR were statistically significant respect to SBP, DBP, basal insulin, insulin/glucose ratio, TG and HDL-C.

Hyperinsulinemia and related atherosclerotic risk factors in the population at cardiovascular risk: a community-based study

BACKGROUND

A population-based study was conducted in Taiwan to investigate the prevalence of insulin resistance and high serum insulin concentrations and their relationships with potential atherosclerotic risk factors.

METHODS

We studied 2165 subjects, ages >35, from a community cohort.

RESULTS

The distributions of fasting insulin were skewed to the right, with higher concentrations in women than in men. As age increased, insulin increased in women, but decreased in men. As fasting insulin concentrations increased, postloading insulin, glucose, blood pressure, body mass index, waist-to-hip ratio, total cholesterol, triglycerides, LDL-cholesterol, apoprotein B, plasminogen activator inhibitor 1, tissue plasminogen activator, and fibrinogen increased, but lipoprotein(a), HDL-cholesterol, and apoprotein A1 decreased. Multiple logistic regression showed that obesity, high LDL-cholesterol, and low HDL-cholesterol were significant predictors of hyperinsulinemic status.

CONCLUSION

The study subjects with insulin resistance syndrome and related risk factors may be at risk for atherosclerosis, thrombosis, and other coronary heart diseases.

Hypertension and related risk factors in type 2 diabetes mellitus

METHODS

The correlation between hypertension and related risk factors has been studied in 733 type 2 diabetic patients. Hypertension was more frequent in women (65.35%) than in men (50.35%) (p < 0.0001).

RESULTS

Hypertensive patients showed older age (p < 0.0001) and greater Body Mass Index (BMI) (p < 0.03) than normotensive. In the diabetic group on diet only basal insulinaemia was higher (p < 0.05) in hypertensive than in normotensive diabetic men, but not in women. Such a difference, was not seen in patients of both sexes treated with oral hypoglycaemic agents; besides there was no difference in fasting C-peptide levels between hypertensive and normotensive insulin treated patients. In both sexes hypertension was independently correlated with age, BMI, increased urinary albumin excretion, triglycerides. The strongest correlation was with the family history of hypertension. On the contrary there was no correlation between hypertension and waisthip ratio.

CONCLUSIONS

In conclusion, the association between hypertension and type 2 diabetes depends on various risk factors, but a relationship with insulin levels is not surely demonstrable.

Clustering of impaired glucose tolerance, hyperinsulinemia and dyslipidemia in young north Indian patients with coronary heart disease: a preliminary case-control study

Metabolic insulin resistance syndrome is a critical factor in the pathogenesis of atherosclerosis and coronary heart disease in Indians. In a preliminary case-control study, 44 young patients (age < 40 years) with coronary heart disease (angina, myocardial infarction), not previously diagnosed to have diabetes mellitus, were recruited seven days to six weeks after the cardiac event (group I), and compared to 20 healthy subjects (group II). After recording history and anthropometric data, they were subjected to oral glucose tolerance test. Each group was divided into A and B subgroups according to the magnitude of impaired glucose tolerance. Hypertension was recorded in 11 (25%) patients in group I, while all the subjects in group II were normotensive (p < 0.05). Groups IB and IIB, consisting of subjects with impaired glucose tolerance displayed significantly high post-load blood glucose values. After excluding patients with the family history of diabetes mellitus, there were 13 (39%) and 3 (17%) patients with impaired glucose tolerance in groups I and II, respectively. Total cholesterol and low-density lipoprotein cholesterol levels were higher in group I as compared to group II (p < 0.01). Group IB showed highest mean values of total cholesterol, triglycerides, low-density lipoprotein cholesterol and lowest level of high-density lipoprotein cholesterol as compared to other subgroups. Serum insulin levels at 30 and 90 minutes were significantly higher in group I (p < 0.05). Group IB and IIB showed higher insulin values at 90 minutes when compared to group IA (p < 0.05) and IIA (p < 0.05). Elevated serum insulin values at 90 minutes during oral glucose tolerance test could differentiate among both groups and subgroups, except IB versus IIB. The study demonstrates significantly high prevalence of hypertension, obesity, impaired glucose tolerance, hyperinsulinemia and dyslipidemia, suggesting fully developed metabolic insulin resistance syndrome in young north Indian patients with manifest coronary heart disease.

Persistent hyperinsulinaemic hypoglycaemia of infancy (nesidioblastosis): a report from Kuwait

We report nine Bedouin children from Kuwait with persistent hyperinsulinaemic hypoglycaemia (PHHI) seen over a 13-year period in two regional hospitals. The incidence of PHHI in this inbred community is high (1:20,000); five of them came from two families. All the children presented with seizures associated with severe and recurrent hypoglycaemia, eight presenting in the neonatal period and one at the age of 2 months. One child died soon after birth. All the others received diazoxide initially, which achieved remission in one while two siblings remain dependent on the drug. Long-acting somatostatin analogue (octreotide) was successfully used in one child. Four children underwent pancreatectomy, two showed diffuse and two had localized nesidioblastosis. Two children achieved normal neurodevelopmental milestones, four suffered mental retardation of varying degrees and three died. Early diagnosis and prompt treatment are essential to avoid the neurological damage associated with hypoglycaemia. In some cases, this condition is due to an autosomal recessive pattern of inheritance and it is therefore important to offer genetic counselling to families with one or more affected siblings.

Performance of a predictive model to identify undiagnosed diabetes in a health care setting

OBJECTIVE

To develop a predictive model to identify individuals with an increased risk for undiagnosed diabetes, allowing for the availability of information within the health care system.

RESEARCH DESIGN AND METHODS

A sample of participants from the Rotterdam Study (n = 1,016), aged 55-75 years, not known to have diabetes completed a questionnaire on diabetes-related symptoms and risk factors and underwent a glucose tolerance test. Predictive models were developed using stepwise logistic regression analyses with the absence or presence of newly diagnosed diabetes as the dependent variable and various items with a plausible connection to diabetes as the independent variables. The models were evaluated in another Dutch population-based study, the Hoorn Study (n = 2,364), in which the participants were aged 50-74 years. Performances of the predictive models were compared by using receiver-operator characteristics (ROC) curves.

RESULTS

We developed three predictive models (PMs), PM1 contained information routinely collected by the general practitioner, while PM2 also contained variables obtainable by additional questions. The third predictive model, PM3, included variables that had to be obtained from a physical examination. These latter variables did not have additive predictive value, resulting in a PM3 similar to PM2. The area under the ROC curve was higher for PM2 than for PM1, but the 95% Cls overlapped (0.74 [0.70-0.78] and 0.68 [0.64-0.72], respectively).

CONCLUSIONS

Using only information normally present in the files of a general practitioner, a predictive model was developed that performed similarly to one supplemented by information obtained from additional questions. The simplicity of PM1 makes it easy to implement in the current health care setting.

Prevalence of the metabolic syndrome in drug-treated hypertensive patients and control subjects

OBJECTIVES

To determine the prevalence of the metabolic abnormalities associated with hypertension and to define the predictors of the metabolic syndrome by different definitions in random population-based samples.

DESIGN

A cross-sectional epidemiological study of hypertensive patients and controls.

SETTING

The participating study subjects visited the research laboratory of the Department of Internal Medicine, University of Oulu, Oulu, Finland.

SUBJECTS

Six hundred treated male and female hypertensives aged 40-59 years and 600 age- and sex-matched controls were randomly selected by age stratification from population registers.

MAIN OUTCOME MEASURES

A wide range of laboratory analyses were conducted. After fasting blood had been drawn, the subjects were given a 75 g glucose load except previously known insulin-treated diabetics. Both 1 h and 2 h glucose and insulin concentrations were determined. During the same visit, a standardized health questionnaire covering the past medical history, current and former medication use, physical activity, smoking habits, alcohol consumption and family history was completed. Ten different definitions of the metabolic syndrome were applied to achieve a wide perspective of the prevalence of the different combinations.

RESULTS

The prevalence of the metabolic syndrome in different samples varied depending on the definition from 0.8 to 35.3%, being lowest in the control men and women and highest in the hypertensive men. Three-quarters of a random, middle-aged, urban population show at least one cardiovascular risk factor and 91.3% of all the hypertensive subjects show at least one cardiovascular risk factor in addition to hypertension itself. The independent predictors of the metabolic syndrome were waist circumference, uric acid, total cholesterol and gamma-glutamyl transpeptidase in logistic analysis after adjustment for age, measure of obesity and gender.

CONCLUSIONS

This cross-sectional, epidemiological study shows that the magnitude of the prevalence rates of the metabolic syndrome is at the same level in various populations, being less than one-third in population-based samples in spite of the different definitions. The cluster of several cardiovascular risk factors, especially in the hypertensives, leads to an increased relative risk of cardiovascular diseases.

Weight gain and the risk of developing insulin resistance syndrome

OBJECTIVE

Obesity and weight gain have been associated independently with hypertension, hyperinsulinemia, and dyslipidemia; however, prior research has not looked at the relation between weight gain from early adulthood to middle age and the development of this cluster of risk factors, known as insulin resistance syndrome.

RESEARCH DESIGN AND METHODS

The association between weight gain over 30 years (defined as the difference between measured weight in middle age and participant recall of their weight at age 20) and the odds of developing insulin resistance syndrome at middle age was examined in a population-based sample of 2,272 eastern Finnish men.

RESULTS

Each 5% increase in weight over the reported weight at age 20 was associated with nearly a 20% greater risk of insulin resistance syndrome by middle age, after adjustment for age and height. Moreover, there was a strong graded association between categories of weight gain and risk of insulin resistance syndrome. Men with weight increases of 10-19%, 20-29%, or > or =30% since age 20 were 3.0, 4.7, or 10.6 times more likely to have insulin resistance syndrome, respectively, by middle age, compared with men within 10% of their weight at age 20. Adjustments for age, height, physical activity, smoking, education, and parental history of diabetes did not alter these findings.

CONCLUSIONS

The odds of having developed the hemodynamic and metabolic abnormalities that characterize insulin resistance syndrome by middle adulthood were increasingly higher the greater the weight gain over the preceding 30 years. This study adds to the literature identifying deleterious effects of weight gain from young to middle adulthood.

Effects of gastroplasty on body weight and related biological abnormalities in morbid obesity

Obesity is a prevalent metabolic disorder associated with high morbidity and mortality rates. Medical treatment rarely succeeds, and bariatric surgery has been proposed as an alternative therapy. The purpose of this non-controlled retrospective study was to evaluate time-course changes in body weight in severely obese patients who underwent vertical ring gastroplasty or adjustable silicone gastric banding, and to assess the prevalence and potential reversibility of several of the biological abnormalities associated with morbid obesity. From an initial cohort comprising 658 patients, regular body weight measurements and biological data were obtained in 505 patients [419 females, 86 males; age 36 +/- 11 years; body mass index 42.7 +/- 6.9 kg/m2; (mean +/- SD)] with a mean follow-up of 26 +/- 14 months. Mean weight loss was 32 +/- 16 kg. Most weight reduction occurred within the first 6 months, followed by near-stabilisation or even slight weight regain. Most biological parameters were obtained before surgery and after at least 6 months of follow-up. The high prevalence and severity of metabolic disturbances associated with the insulin resistance syndrome (hyperglycaemia, hyperinsulinaemia, decreased HDL cholesterol, hypertriglyceridaemia, elevated fibrinogen levels and hyperuricaemia) before gastroplasty were significantly decreased after weight loss. No major biological deficiencies were observed following gastroplasty, except low iron serum levels. It is concluded that marked weight loss associated with gastroplasty involved a remarkable reduction in the prevalence and severity of several biological abnormalities classically considered as cardiovascular risk factors.

Hyperinsulinemia predicts coronary heart disease risk in healthy middle-aged men: the 22-year follow-up results of the Helsinki Policemen Study

BACKGROUND

The Helsinki Policemen Study is one of the first prospective epidemiological studies demonstrating an association of hyperinsulinemia to the risk of coronary heart disease (CHD). The aim of the present study was to investigate the predictive value of hyperinsulinemia with regard to CHD risk during a 22-year follow-up of the Helsinki Policemen Study population.

METHODS AND RESULTS

The study was based on a cohort of 970 men who were 34 to 64 years of age and free of CHD, other cardiovascular disease, and diabetes. Risk factor measurements at baseline examination included an oral glucose tolerance test (OGTT) with blood glucose and plasma insulin measurements at 0, 1, and 2 hours. Area under the plasma insulin response curve (AUC insulin) during OGTT was used as a composite variable reflecting plasma insulin levels. During the 22-year follow-up, 164 men had a major CHD event (CHD death or nonfatal myocardial infarction). Age-adjusted hazard ratios for a major CHD event comparing men in the highest AUC insulin quintile with those in the combined 4 lower quintiles during 5-, 10-, 15-, and 22-year follow-up periods were 3.29 (95% CI, 1.56 to 6.91), 2.72 (95% CI, 1.67 to 4.42), 2.14 (95% CI, 1.43 to 3.21), and 1.61 (95% CI, 1.14 to 2.27), respectively. Further adjustment for other risk factors attenuated these hazard ratios to 2.36 (95% CI, 1.00 to 5.57), 2.29 (95% CI, 1.31 to 4.02), 1.76 (95% CI, 1.09 to 2.82), and 1.32 (95% CI, 0.89 to 1.97), respectively.

CONCLUSIONS

Hyperinsulinemia predicted CHD risk in Helsinki policemen over the 22-year follow-up, and to a large extent independently of other CHD risk factors, but its predictive value diminished with lengthening follow-up time.

Fetal growth and hyperinsulinaemia in adult life

To explore the relation between reduced fetal growth and impaired glucose tolerance in adult life, an oral glucose tolerance test (75 g glucose) was carried out on 218 men and women, now aged around 50 years, who had been measured in detail at birth. Measurements of plasma concentrations of glucose and insulin were made at 0, 30, and 120 min. Fasting plasma concentrations of proinsulin and 32-33 split proinsulin were also measured. People in the highest category of birthweight tended to have the lowest plasma concentrations of insulin as adults at both 0 and 120 min, though both these relations were weak. Plasma insulin concentrations in adult life were more strongly related to abdominal circumference at birth than to birthweight. After adjusting for sex and body mass index, mean insulin concentrations at 0 min fell from 50 pmol l-1 to 46 pmol l-1 (p = 0.04) and at 120 min from 235 pmol l-1 to 144 pmol l-1 (p = 0.003) between people whose abdominal circumference at birth had been less than 11.5 in and those who abdominal circumference had been greater than 13 in. Plasma glucose concentrations at 120 min also fell with increasing abdominal circumference at birth. Because abdominal circumference at birth is an indicator of the growth of the liver in fetal life, one interpretation of these findings is that the sensitivity of the liver to insulin is permanently reduced if the intrauterine development of this organ is impaired.

Neonatal morbidities in gestational diabetes mellitus

The currently accepted definition of gestational diabetes mellitus (GDM) is rather broad. One might expect that fetal and neonatal complications that may occur in GDM pregnancy would be similar to those in pregestational diabetic pregnancy. Comparative evaluation of reported data on morbidity in GDM are often hampered by confounding variables (maternal age, parity, obesity) as well as the influence of factors such as ethnic origin, diagnostic criteria, and intervention during pregnancy. Recent observations indicate that GDM may be associated with increased incidence of fetal malformation and perinatal mortality. Such poor outcome is likely confined to a subset of GDM patients in whom diabetes was present but unrecognized before pregnancy. The most frequent and significant morbidity is fetal macrosomia, which in turn is associated with increased risk of birth injuries and asphyxia. In a nationwide study in Sweden (1991-1993) of a large series (n = 3.322) of treated GDM pregnancies, perinatal mortality rate was not increased; but the rate of preeclampsia was doubled, and the rate of emergency cesarean section was 1.6 times higher than in the background population. The rates of fetal macrosomia (> or = 4,500 g), asphyxia, and transient tachypnea were two to three times higher than normal Erb's palsy was 0.7 and 5% in vaginally delivered infants weighing < 4,500 and > or = 4,500 g, respectively. There is a clear need to define the various levels of glucose intolerance in the mother that may have an adverse effect on the offspring. Of equal importance is to standardize and systematize the criteria used to assess the significance of any such impact.

Insulin resistance, hyperinsulinemia, and hypertriglyceridemia in patients with coronary artery disease independent of obesity

Insulin resistance and hyperinsulinemia both in normal persons and those with non-insulin dependent diabetes mellitus (NIDDM) (type 2 diabetes) appears to be related to obesity. It seems also that insulin plays a role in modulating the obesity-related factors (eg, hyperinsulinemia, hyperglycemia, hypertension, hypertriglyceridemia, hypercholesterolemia, low concentrations of high-density lipoprotein cholesterol) and takes its place among the many risk factors for coronary artery disease (CAD) associated with obesity. Insulin resistance and hyperinsulinemia could play the same role in pathogenesis of CAD independently of obesity. The authors determined blood glucose and immunoreactive insulin and plasma triglyceride concentrations in the fasting state at 60 and 120 minutes after a glucose load of 75 g in 68 patients (54 men, 14 women) with angiographic evidence of CAD and in 65 healthy volunteers matched to the patients for age, gender, and body mass index (43 men and 22 women). Patients with CAD and the healthy volunteers were categorized as obese (body mass index > or = 26 kg/m2) and nonobese (body mass index < 26 kg/m2). Four groups of subjects were analyzed: Group A included 40 healthy (28 men and 12 women) nonobese volunteers; group B, 25 healthy (15 men and 10 women) obese volunteers; group C, 39 (30 men and 9 women) nonobese patients with CAD; and group D, 29 (24 men and 5 women) obese patients with CAD. Fasting and postchallenged 60- and 120-minute glucose values were similar in groups A and C. However, significantly higher insulin values (mU/L) were observed in group C than in group A during fasting (12.2+/-6.2 vs 91+/-3, p<0.05), and postchallenged at 60 minutes (103.1+/-53.2 vs 71.9+/-64.3, p<0.01) and 120 minutes (57.9+/-41.2 vs 44.9 +/-41.3, p<0.01). Fasting glucose and insulin values were similar in groups B and D. However, significantly higher glucose (mg/dL) and insulin values were observed in group D than in group B postchallenged at 60 and 120 minutes: glucose at 60 minutes (188.7 +/-45.1 vs 154.2+/-37.5, p<0.05); insulin at 60 minutes (127.5+/-98.5 vs 112.1+/-81.1, p<0.05); glucose at 120 minutes (124.2+/-46.1 vs 99.5+/-28.9, p<0.05); insulin at 120 minutes (86.1+/-57.6 vs 62.8+/-27.9, p<0.05). The glucose and insulin values during 60- and 120-minute fasting as well as postchallenged were similar in groups B and C. Significantly higher plasma triglyceride concentrations were observed in group C than in group A (149.0+/-64.1 vs 114.6+/-46.6, p<0.01) and in group D compared with group B (229.4+/-104.7 vs 144.9+/-65.1, p<0.001). Plasma triglyceride concentrations were similar in groups B and C. The authors conclude that patients with documented CAD are insulin resistant independently of obesity.

Hyperinsulinaemia in hypertensive subjects: validity of a test for the detection of insulin resistance in clinical practice

OBJECTIVES

To determine the prevalence of hyperinsulinaemia in non-diabetic hypertensive subjects and to investigate the validity of a simple test for the detection of insulin resistance/hyperinsulinaemia. The test consisted of five markers: (1) obesity (body-mass index, BMI > or =30 kg/m2); (2) central adiposity (waist-to-hip ratio, WHR > or =1.00 in men and > or =0.88 in women); (3) hypertriglyceridaemia (> or =1.70 mmol/l); (4) low high-density lipoprotein (HDL) cholesterol (<1.00 mmol/l in men and <1.20 mmol/l in women); and (5) impaired glucose tolerance according to the WHO criteria. The test was defined to be positive for subjects who had simultaneously at least two of the five markers.

DESIGN AND SETTING

A community-based screening programme for hypertension carried out at Pieksämäki District Health Centre, and the Community Health Centre of the City of Tampere, Finland.

SUBJECTS

The 161 hypertensives who were detected by screening all subjects aged 36, 41, 46 and 51 years (n = 1148) in Pieksämäki town, and a randomly selected normotensive control group of 177 men and women aged 40 and 45 years in the City of Tampere.

MAIN OUTCOME MEASURES

Hyperinsulinaemia defined by using two different cut-off points of the fasting plasma insulin (> or =13.0 mU/l and > or =18.0 mU/l).

RESULTS

Hyperinsulinaemia > or =13.0 mU/l was present in 45% of hypertensive men and in 25% of hypertensive women. The sex difference was statistically significant (P < 0.01). The corresponding rates of hyperinsulinaemia > or =18.0 mU/l were 18% and 16%. The sensitivity of the test for hyperinsulinaemia > or =13.0 mU/l was 77% and specificity 73% in men, and 100% and 70% in women. The corresponding figures for hyperinsulinaemia > or =18.0 mU/l were 94% and 60% in men, and 100% and 63% in women.

CONCLUSION

Our results suggest that hyperinsulinaemia/insulin resistance in hypertensives becomes identifiable by using simple measurements of BMI, WHR, serum triglycerides and HDL cholesterol as well as the oral glucose tolerance test as means.

Obesity type and clustering of insulin resistance-associated cardiovascular risk factors in middle-aged men and women

OBJECTIVE

To examine different clusterings of the insulin resistance-associated cardiovascular risk factors with respect to different types of obesity.

DESIGN

A screening programme for obesity (body mass index; BMI> or =30 kg/m2) and abdominal adiposity (waist-to-hip ratio; WHR > or = 1.00 in men and > or = 0.88 in women).

SETTINGS

Pieksämäki District Health Centre and the Community Health Centre of the City of Tampere, Finland.

SUBJECTS

All volunteers were either aged 36, 41, 46 or 51 y (n=1148) and living in the town of Pieksämäki, with a control population of 162 subjects in the City of Tampere.

MAIN OUTCOME MEASURES

Different clusterings of: 1) hypertension (a systolic blood pressure > or = 160 mmHg and/or a diastolic blood pressure > or = 95 mmHg or concurrent drug treatment for hypertension); 2) hypertriglyceridaemia > or = 1.70 mmol/l; 3) a low level of high-density-lipoprotein (HDL) cholesterol; < 1.00 mmol/l in men, < 1.20 mmol/l in women; 4) abnormal glucose metabolism (impaired glucose tolerance or non-insulin-dependent diabetes) and 5) hyperinsulinaemia with a fasting plasma insulin > or = 13.0 mU/l.

RESULTS

The prevalence of a cluster consisting of dyslipidaemia (hypertriglyceridaemia and/or low HDL-cholesterol) and insulin resistance (abnormal glucose metabolism and/or hyperinsulinaemia) was found to be 4% in the control subjects, 18% in the abdominal adipose subjects (WHR > or = 1.00 in men and > or = 0.88 in women with a BMI < 30 kg/m2), 28% in the 'pure' obese subjects (BMI> or = 30 kg/m2 with WHR < 1.00 in men and < 0.88 in women), and 46% in the central obese subjects (subjects showing both 'pure' obesity and abdominal adiposity). The prevalence rates of the other clusterings of abnormalities varied similarly according to the type of obesity.

CONCLUSION

Clusterings of insulin resistance-associated abnormalities were related to the type of obesity in both middle-aged men and middle-aged women.

Obesity induced by neonatal monosodium glutamate treatment in spontaneously hypertensive rats: an animal model of multiple risk factors

The present study was designed to develop an animal model of multiple risk factors, including obesity, hypertension, non-insulin-dependent diabetes mellitus, and hyperlipidemia. Hypothalamic obesity was induced by neonatal monosodium glutamate (MSG) treatment in spontaneously hypertensive rats (SHR). Female newborn SHR were treated intraperitoneally with 2 or 4 mg/kg body weight of MSG for 5 days. Obesity developed in SHR treated with 4 mg/kg of MSG but not in SHR treated with 2 mg/kg of MSG. Obese SHR had impaired glucose tolerance, hyperinsulinemia, and hypertriglyceridemia. However, the severity of hypertension was attenuated in obese SHR as compared with control SHR. The degree of obesity was closely related to the metabolic abnormalities, but inversely correlated with the blood pressure level. Macrovascular changes were investigated in obese SHR at 14 months of age. Intimal thickening was accelerated in the carotid artery of obese SHR as compared with that of nonobese SHR. Aortic contents of DNA and total cholesterol were significantly increased in obese SHR. SHR associated with MSG-induced obesity showed major manifestations of metabolic syndrome X. This animal model may be useful to study the clustering of risk factors for the development of macrovascular diseases.

Study of genetic prediabetic south Indian subjects. Importance of hyperinsulinemia and beta-cell dysfunction

OBJECTIVE

To study 1) whether abdominal adiposity was present in adult offspring of two NIDDM parents, 2) whether abdominal adiposity was associated with the development of glucose intolerance, and 3) the association of pancreatic beta-cell function with impaired glucose tolerance (IGT) and NIDDM in these groups.

RESEARCH DESIGN AND METHODS

One hundred offspring whose parents both had NIDDM were studied (60 men, 40 women, mean age 34 +/- 6.9 years, BMI 27.4 +/- 4.1 kg/m2). None had a history of glucose intolerance. Nondiabetic control subjects with no family history of diabetes were also studied for comparison (21 men, 19 women, age 36 +/- 10.3 years, BMI 26 +/- 3.7 kg/m2). A standard oral glucose tolerance test was done for all, and plasma glucose, C-peptide, and insulin responses were measured. Abdominal fat measurements at L4-L5 were made using a computed axial tomography scan. Subcutaneous fat (SF), visceral fat (VF), and total fat (TF) areas were measured and VF/SF ratio was calculated. An index of insulin secretion (delta I/G) was derived as the ratio of incremental insulin at 30 min divided by 30-min plasma glucose.

RESULTS

IGT was detected in 32 offspring and diabetes in 21 offspring. Diabetic men had a higher TF area than the other groups. SF, VF, and VF/SF ratios were similar in control men and in offspring with normal glucose tolerance (NGT), IGT, or diabetes. Among control subjects, women had significantly lower VF than men. Female offspring had higher VF than the control subjects, but intragroup variations were absent. Fasting insulin and all C-peptide responses were higher in NGT compared with control subjects (P < 0.02). The 2-h insulin and C-peptide responses were higher in IGT subjects (P < 0.005). In diabetic subjects, the insulin-to-glucose ratio, C-peptide-to-glucose ratio, and delta I/G were significantly low compared with all other groups (P < 0.005). Multiple logistic regression analysis showed that the area of insulin response had a positive association and delta I/G had a negative association with diabetes, while age, sex, BMI, waist-to-hip ratio, abdominal fat areas, fasting and 2-h insulin, area of insulin, and the C-peptide measurements did not show independent associations. Two-hour insulin showed a positive association with IGT, while increasing area of insulin showed a negative association.

CONCLUSIONS

Visceral adiposity seemed to precede glucose intolerance only in women, but it had no independent association with IGT or NIDDM. Insulin resistance, indicated by higher plasma insulin response, and insulin secretory defect, indicated by low delta I/G at 30 min, were associated with diabetes. beta-cell defect was not independently associated with IGT. Increased abdominal visceral adiposity does not appear to be a prerequisite for development of IGT or diabetes in Asian Indians with a strong genetic predisposition for diabetes.

Association between features of the insulin resistance syndrome and Alzheimer's disease independently of apolipoprotein E4 phenotype: cross sectional population based study

OBJECTIVE

To determine the association between features of the insulin resistance syndrome and Alzheimer's disease.

DESIGN

Cross sectional population based study.

SUBJECTS

980 people aged 69 to 78 (349 men, 631 women).

SETTING

Population of Kuopio, eastern Finland.

MAIN OUTCOME MEASURES

Presence of features of the insulin resistance syndrome and diagnosis of Alzheimer's disease by detailed neurological and neuropsychological evaluation.

RESULTS

46 (4.7%) subjects were classified as having probable or possible Alzheimer's disease. In univariate analyses, apolipoprotein E4 phenotype (odds ratio; 95% confidence interval 3.24: 1.77 to 5.92), age (1.16; 1.05 to 1.29), low level of education (0.82; 0.72 to 0.93), low total cholesterol concentration (0.77; 0.59 to 1.00), high systolic blood pressure (1.01; 1.00 to 1.03), high fasting and 2 hour plasma glucose concentrations (1.11; 1.01 to 1.23 and 1.08; 1.03 to 1.13, respectively), high fasting and 2 hour insulin concentrations (1.05; 1.02 to 1.08 and 1.003; 1.00 to 1.01, respectively), and abnormal glucose tolerance (1.86; 1.23 to 2.80) were significantly associated with Alzheimer's disease. In multivariate analysis including apolipoprotein E4 phenotype, age, education, systolic blood pressure, total cholesterol concentration, fasting glucose concentration, and insulin concentration, apolipoprotein E4 phenotype, age, education, total cholesterol, and insulin were significantly associated with Alzheimer's disease. In 532 non-diabetic subjects without the e4 allele hyperinsulinaemia was associated with an increased risk for Alzheimer's disease (prevalence of disease 7.5% v 1.4% in normoinsulinaemic subjects, P = 0.0004). In contrast, in the 228 with the e4 allele hyperinsulinaemia had no effect on the risk of disease (7.0% v 7.1%, respectively).

CONCLUSION

Features of the insulin resistance syndrome are associated with Alzheimer's disease independently of apolipoprotein E4 phenotype.

[Lipid metabolic disorders in obesity: their epidemiology, physiopathology and clinico-therapeutic implications]

The centralization of body fat, particularly in abdominal or visceral depots, is associated with qualitative and quantitative lipid abnormalities. Examples of these qualitative alterations include changes in low density lipoprotein composition, namely an increased number of small or dense low density lipoprotein particles, which seem to be prone to increased lipid oxidation. Oxidative modification of low density lipoproteins is involved in atherosclerotic development of the arterial wall. Alterations of lipid composition often arise in a context of insulin resistance with hyperinsulinism. Genetic features, such as apolipoprotein E polymorphism, also play a significant role in lipoprotein metabolism. The principle treatment of obesity and associated dyslipidemia is to reduce energy intake through diet. Moderate exercise is effective, especially in patients with insulin resistance. Drug therapy is considered primarily for patients who refuse to make behavioral changes.

[Insulin resistance and essential hypertension in Vietnamese subjects]

Several epidemiological and experimental studies suggest that essential arterial hypertension is associated with hyperinsulinism and insulin resistance in obese subjects and also in subjects with normal body weight. Undernutrition remains frequent in adult Vietnamese people and mean body mass index is around 18.5 kg/m2 in Vietnam. The aim of this study was to look for insulin resistance in hypertensive Vietnamese subjects, despite a markedly lower BMI in Vietnam than in occidental countries. One hundred and eight hypertensive patients (51 men and 57 women) over 40 years (mean = 65.4 years) were compared with 36 healthy subjects (23 men and 13 women) over 40 years (mean = 63.8 years). Hypertensive patients had significantly higher BMI (20.5 +/- 0.3 (SEM) kg/m2 vs 18.4 +/- 0.4 kg/m2; p < 0.01), thicker triceps skinfold (1.26 +/- 0.07 cm vs 0.71 +/- 0.07 cm; p < 0.001) and not significantly different waist/hip ratio (0.88 +/- 0.01 vs 0.85 +/- 0.01). Blood glucose at fasting and 2 hours after 75 g glucose taken orally were similar in hypertensive and normotensive subjects. Plasma insulin at fasting and 2 hours after glucose were significantly higher in hypertensive patients (44.4 +/- 5.1 pmol/L vs 21.6 +/- 3.2 pmol/L; p < 0.05 and 271.1 +/- 21.6 pmol/L vs 139.1 +/- 15.2 pmol/L; p < 0.001). Thus, despite under-nutrition, hypertensive Vietnamese patients have a moderate but significant increase in BMI and fat mass without predominant abdominal localization, and a state of insulin-resistance, compared with normotensive healthy subjects.

Hyperinsulinemia and acanthosis nigricans in African Americans

Compared with the US white, non-Hispanic population, the African-American population has a nearly two-fold higher prevalence of noninsulin-dependent diabetes mellitus (NIDDM). Obesity, which usually precedes NIDDM, is associated with the skin lesion acanthosis nigricans in African Americans. This study was undertaken to determine what the relationship of acanthosis nigricans was to hyperinsulinemia, a major risk factor for NIDDM. Eighty-nine African-American subjects with acanthosis nigricans and 25 others without the skin lesion were evaluated using oral glucose tolerance testing and responsiveness to insulin. Noninsulin-dependent diabetes mellitus was present in 19 of the subjects with acanthosis nigricans. The prevalence of NIDDM in this group increased with increasing age, reaching 50% among those in their 40s. Fasting plasma insulin concentration was in direct proportion to the severity of the acanthosis nigricans involvement of the neck. These data suggest that among African Americans, this skin lesion is a marker for hyperinsulinemia and insulin resistance. Furthermore, the presence of acanthosis nigricans identifies a subset with a much higher prevalence of NIDDM than is present in African Americans in the general population.

High saturated fat and low starch and fibre are associated with hyperinsulinaemia in a non-diabetic population: the San Luis Valley Diabetes Study

A geographically based sample of 1069 Hispanic and non-Hispanic white persons aged 20-74 years, living in southern Colorado and who tested normal on an oral glucose tolerance test (World Health Organization criteria) were evaluated to determine associations of dietary factors with fasting serum insulin concentrations. Subjects were seen for up to three visits from 1984 to 1992. A 24-h diet recall and fasting insulin concentrations were collected at all visits. In longitudinal data analysis, lower age, female gender, Hispanic ethnicity, higher body mass index, higher waist circumference, and no vigorous activity were significantly related to higher fasting insulin concentrations. High total and saturated fat intake were associated with higher fasting insulin concentrations after adjusting for age, sex, ethnicity, body mass index, waist circumference, total energy intake and physical activity. Dietary fibre and starch intake were inversely associated with fasting insulin concentrations. No associations with fasting insulin concentrations were observed for monounsaturated fat, polyunsaturated fat, sucrose, glucose and fructose intake. Associations were similar in men and women and for active and inactive subjects, though associations of fibre and starch intake with insulin concentrations were strongest in lean subjects. These findings support animal studies and a limited number of human population studies which have suggested that increased saturated and total fat intake and decreased fibre and starch intake increase fasting insulin concentrations and may also increase insulin resistance. These findings, which relate habitual macronutrient consumption to hyperinsulinaemia in a large population, may have implications for studies attempting primary prevention of non-insulin-dependent diabetes mellitus.

[Prevalence of glucose intolerance, diabetes mellitus, and high serum insulin levels in a Japanese urban population]

An epidemiological study was conducted to investigate the prevalence of diabetes mellitus, glucose intolerance and hyperinsulinemia in an urban population. Twelve thousand two hundred people aged 30 to 79 were randomly selected from residents of S-city in Osaka Prefecture and were urged to attend a cardiovascular examination at the National Cardiovascular Center. In 1992 and 1993, among 5,284 people who received the examination, 75 g oral glucose tolerance tests (OGTT) were performed and plasma glucose and serum insulin concentrations were determined for 2,147 subjects, who participated in the morning course of examination and who were fasting. The prevalence of diabetes and hyperinsulinemia (fasting serum insulin level > or = 15 microU/ml) was higher in older than in the younger generation, and was higher in men than in women. The prevalence of diabetes in those aged 40 and over in S-city was 7.3% in men and 5.6% in women, 17.2% of men and 10.7% of women had impaired glucose tolerance, and 7.5% of men and 5.2% of women had hyperinsulinemia. A comparison of prevalences of diabetes was performed between 4 populations, one being our urban population and others being 3 rural populations where population-based surveys had been accomplished with OGTT but without a screening as ours was with regard to detecting diabetes. The prevalence of diabetes in our urban population did not appear to be higher than in the other 3 rural populations. From a questionnaire survey of responders and non-responders to OGTT, it was considered that the degree of selection bias in this study was small, if any.

Hyperinsulinemia in patients with coronary heart disease in absence of overt risk factors

The objective of the study was to determine if male subjects with coronary atherosclerotic heart disease (CHD) without major CHD risk factors have hyperinsulinemia and related metabolic changes. Previous studies suggested that hyperinsulinemia is a CHD risk factor, but they did not entirely exclude concurrent metabolic abnormalities. A prospective, comparative, cross-sectional study in a tertiary care teaching hospital in Mexico City was conducted in 15 men who had suffered myocardial infarction 6 to 24 months before and had significant coronary occlusion on angiography. Control group was formed by 15 age-matched healthy men. None had hypertension, obesity, diabetes, gout, glucose intolerance or hyperlipidemia. Body mass index (BMI), waist/hip ratio (WHR), blood pressure (BP); oral glucose tolerance test (OGTT) with measurement of serum glucose, insulin and C-peptide every 30 min for 2 h, fasting serum cholesterol, triglycerides and uric acid, areas under curve (AUC) of glucose and insulin, insulin/glucose ratio and insulin sensitivity index were calculated. BMI, WHR and BP were similar in both groups. Fasting and post-load serum glucose and insulin concentrations were significantly higher in CHD than in control group (p < 0.01); fasting glucose 5.9 +/- 0.6 vs. 4.8 +/- 0.7 nmol/1, 2-h glucose 8.3 +/- 0.6 vs. 7.3 +/- 0.9 mmol/l, fasting insulin 17.5 +/- 1.2 vs. 15.3 +/- 1.7 pmol/l, 2 h insulin 448 +/- 108 vs. 282 +/- 87 pmol/l in CHD and control group, respectively. AUC of glucose, AUC of insulin, insulin/glucose ratio, post load C-peptide, serum cholesterol, triglycerides and uric acid levels were also significantly higher in CHD than in healthy controls. Insulin sensitivity index was significantly lower in patients with CHD (27.7 +/- 8.3) than in healthy control subjects (73.9 +/- 18) (p < 0.001). Patients with CHD have hyperinsulinemia and subtle metabolic abnormalities related with insulin resistance even in absence of overt risk factors.

Lipoprotein(a) and cardiovascular risk in adult Mexicans

A cross-epidemiologic study concerning cardiovascular risk factors in a random sample population of Mexico City was carried out in 1991 and 1992. Lipoprotein(a) (Lp(a)) levels in 404 men and 311 women aged 20-90 years were determined by enzyme-linked immunoassay on fasting plasma. Men and women showed similar age-adjusted Lp(a) values. For the whole population the median Lp(a) was 6.9 mg/dL and the prevalence of high Lp(a) (> 30 mg/dL) was 14%. Small positive correlations between Lp(a) and plasma cholesterol (rs = 0.16) and low density lipoprotein cholesterol (LDL-C) (rs = 0.21), and a negative one with insulin (rs = -0.13) were found. In a multiple regression analysis, insulin and LDL-C were the variables that best explained the variation of Lp(a) in our sample. Our data show that Lp(a) in our population is similar to that found in other populations. An association of Lp(a) with myocardial infarction was observed (high Lp(a) was seen in 33% of atherosclerotic individuals versus 14% in healthy subjects) but did not reach statistical significance.

Prevalence of hyperinsulinemia in young, nonobese Japanese men

OBJECTIVE

To clarify the prevalence of hyperinsulinemic subjects among young, nonobese, Japanese men, and to evaluate characteristics, in particular, of sympathetic nerve system activity and lipid fractions in hyperinsulinemic subjects.

METHODS

Norepinephrine, plasma insulin, and lipid fractions were measured in 512 normotensive, 124 borderline hypertensive (BHT) and 88 established hypertensive (EHT) subjects, matched for age and body mass index, after they had fasted overnight.

RESULTS

Hyperinsulinemia defined as mean fasting plasma insulin + 2SD in normotensives or more was found in 8% of all subjects (normotensive and hypertensive subjects, P = 0.018), 6% of normotensives, 10% of BHT (P = 0.28, versus normotensives), 18% of EHT (P = 0.005, versus normotensives), and 12% of hypertensives (P = 0.019, versus normotensives). The hyperinsulinemic (fasting insulin > or = mean + 2SD in normotensive) subjects had higher plasma norepinephrine levels in all blood pressure groups than did nonhyperinsulinemic (< mean + 2SD) subjects (normotensives P < 0.05, BHT P < 0.01, and EHT P < 0.05). Hyperinsulinemic normotensives had higher blood pressure levels than did nonhyperinsulinemic ones (P < 0.05); however, blood pressure levels in hyperinsulinemic BHT and EHT were similar to those in nonhyperinsulinemic subjects. Triglyceride in BHT and EHT was greater than that in normotensives (P < 0.05), and that in hyperinsulinemic subjects was greater than that in nonhyperinsulinemic subjects (P < 0.05). On the other hand, high-density lipoprotein cholesterol in hyperinsulinemic BHT and EHT was significantly lower than that in nonhyperinsulinemic BHT (P < 0.05) and EHT (P < 0.01).

CONCLUSION

These results demonstrated that the prevalence of hyperinsulinemia among the present sample of young, nonobese, Japanese men was 12% and that the prevalence increased with blood pressure elevation. Furthermore, hypertriglyceridemia and sympathetic nerve hyperactivity appear to be related to hyperinsulinemia and the emergence of hypertension.

The metabolic syndrome: from inherited survival trait to a health care problem

A critical role is proposed for the quantity and quality of dietary carbohydrate in the pathogenesis of the insulin resistance and hyperinsulinaemia which characterise the Metabolic Syndrome. We propose that an insulin-resistant genotype evolved to provide survival and reproductive advantages for the cold-climate, large game hunters of the last Ice Age who consumed a low carbohydrate, high protein diet with periodic starvation. Insulin resistance would have minimised glucose utilisation by muscles thereby facilitating the preferential utilisation of glucose by the brain, foetus and mammary gland. But beginning about 10,000 years ago following the end of the last Ice Age and the development of agriculture, dietary carbohydrate increased and the selection pressure for insulin resistance decreased in some groups. Agriculture began in the Middle East and spread throughout Europe long before it was developed elsewhere. Hence the prevalence of the insulin-resistant genotype decreased in Europeans and other groups exposed to a high carbohydrate intake for sufficiently long. Some geographically isolated groups such as the Pima Indians and Nauruans experienced conditions which further diminished the gene pool diversity and resulted in particularly insulin resistant populations. Traditional carbohydrate foods have a low glycaemic index and produce only modest increases in plasma insulin. However, the constant supply of highly refined high glycaemic index carbohydrate in modern diets, results in postprandial hyperinsulinaemia. The insulin-resistant genotype is now disadvantageous and predisposes to the development of the Metabolic Syndrome.

Diabetes mellitus, impaired glucose tolerance, and hyperinsulinemia in an elderly population. The Rotterdam Study

To estimate the prevalence of glucose intolerance in the elderly, oral glucose tolerance tests were performed as part of the Rotterdam Study, a population-based study in subjects aged 55 years and over. The study population consisted of 2,668 men and 3,950 women. Diabetes mellitus was defined as the use of antidiabetes medication, or a random or post-load serum glucose level of > or = 11.1 mmol/liter. Impaired glucose tolerance was defined as a post-load serum glucose between 7.8 and 11.1 mmol/liter. In men, the frequency of diabetes mellitus ranged from 5.9% in ages < 60 years to 19.8% in ages > 85 years, and in women from 3.8% in ages < 60 years to 18.9% in ages > 85 years; more than half of the subjects with diabetes were newly diagnosed. The prevalence of impaired glucose tolerance ranged from 8.8% and 11.0% in men and women aged < 60 years to 24.3% and 34.7% in men and women aged > 85 years. The prevalence of diabetes mellitus in the total Rotterdam Study population of 7,439 elderly men and women was estimated to be 11.3% (95% confidence interval (CI) 10.5-12.0). Waist/hip ratio, systolic blood pressure, hypertension, and number of cigarettes smoked increased with a worsening of the glucose tolerance from normal, hyperinsulinemia, impaired glucose tolerance to diabetes in both men and women (p < 0.01, adjusted for age). Body mass index was higher in subjects with glucose intolerance, but the frequency of obesity showed a relative decrease with worsening of glucose tolerance. These results show that glucose intolerance, especially impaired glucose tolerance and undetected diabetes mellitus, is common in the elderly. Moreover, not only subjects with diabetes mellitus but also subjects with hyperinsulinemia and impaired glucose tolerance have an increase of cardiovascular risk factors.

[Endocrine tumors of the pancreas at a Mexican institution]

OBJECTIVE

To analyze characteristics of patients with endocrine tumors of the pancreas seen between 1960 and 1992 at the Instituto Nacional de la Nutrición.

MATERIAL & METHODS

The clinical records of 38 patients with endocrine tumors of the pancreas were reviewed. Overall characteristics, diagnostic studies, intraoperative findings, treatment and outcome were analyzed. The archival histological specimens were revised and immunohistochemical stainings were performed in the non-functioning tumors.

RESULTS

Twenty patients had hyperinsulinism, 10 non-functioning tumors, and eight a Zollinger-Ellison syndrome. The mean age of patients with hyperinsulinism was 38 years (8 males and 12 females); 18 were sporadic and two associated with MEN I syndrome. In 16 patients an insulinoma was removed: (6 in the head, 5 in the body, 5 in the tail of the pancreas). A cure was documented in 14 patients with sporadic tumors but not in the two cases associated with MEN I; 15 tumors were benign. Three patients with the Zollinger-Ellison syndrome were males and five females with a mean age of 41 years. Seven tumors were sporadic and one associated with the MEN I syndrome; 70% were located in the gastrinoma triangle. Local excision was performed in five and gastrectomy in three. The cure rate was 60% and malignancy was documented in 40%. Two males and eight females with a mean age of 30 years had non-functioning tumors (9 sporadic and one associated to MEN I). There was a positive immunohistochemistry in 60% of the tumors; 90% were malignant and the cure rate was 10%.

CONCLUSIONS

Insulinoma is the most common endocrine tumor of the pancreas in our hospital. The cure rate for insulinomas, gastrinomas and non-functioning tumors was 90%, 60% and 10% and malignancy was documented in 5%, 40% and 90% respectively.

Insulin resistance and cardiovascular complications in patients with essential hypertension

Hyperinsulinemia or insulin resistance is suggested to play a role in the pathogenesis of hypertension and its target organ diseases. We designed this study to evaluate the role of insulin resistance in cardiac function, cardiac hypertrophy, wall thickness of the common carotid artery, and endothelial function of the brachial artery in essential hypertensive patients without diabetes mellitus. Insulin resistance was evaluated by the constant glucose infusion rate (M value) during the euglycemic-hyperinsulinemic glucose clamp test. In correlation analysis for several indices of glucose metabolism, only M value correlated with left ventricular mass index (LVMI), ratio of peak velocity during atrial contraction to that during early left ventricular filling phase (E/A ratio) and intima-media complex (IMC). In stepwise regression analysis of various risk factors for cardiovascular diseases, only M value and age were dependent factors for LVMI, E/A ratio, and IMC. No indices of glucose metabolism or risk factors for cardiovascular diseases correlated with endothelium-dependent and -independent vasodilation. These results suggest that insulin resistance, but not glucose intolerance and hyperinsulinemia, partly accelerates cardiovascular complications such as left ventricular hypertrophy and wall thickening of the carotid artery in patients with essential hypertension.

Non-insulin-dependent diabetes mellitus (NIDDM) in Korea

The prevalence of diabetes mellitus in Korea has increased tremendously during the past several decades. In addition to the explosive increase of diabetes mellitus, the clinical characteristics of diabetes mellitus in Korea seems to be quite different from those of Western countries. Most patients with non-insulin-dependent diabetes mellitus (NIDDM) are non-obese and many of them lose weight significantly during the course of developing diabetes. The pathogenic mechanism(s) underlying this phenotype is still unclear. A subgroup of patients known as slow onset IDDM exists, but this could not explain the majority of non-obese NIDDM in Korea. In order to examine whether insulin resistance/hyperinsulinaemia is important in the development of NIDDM we conducted the following studies. Fasting plasma glucose and insulin concentration were measured in subjects with normal glucose tolerance, impaired glucose tolerance and diabetes mellitus. The peak plasma insulin level was much lower than that of Pima Indians or Caucasians. We also found that the insulin sensitivity index measured by euglycemic hyperinsulinaemic clamp in the first degree relatives of Korean NIDDM patients was not lower than that in a control group. This data suggests that insulin resistance, or hyperinsulinaemia, does not play a major role in the development of NIDDM in Korea. Taken together with the rarity of obese NIDDM in Korea, it maybe suggested that the insulin secretory capacity of Korean people being smaller than Western people they cannot compensate for the insulin resistance imposed by recent changes in life style.

Risk factors for vascular disease and arteriovenous fistula dysfunction in hemodialysis patients

Vascular access dysfunction is an important cause of morbidity for dialysis patients and a major contributor to hemodialysis cost. Thrombosis is a leading cause of vascular access failure, and usually results from stenotic lesions in the venous outflow system. This study was designed to explore the impact of serum levels of various risk factors for thrombosis and accelerated fibrointimal hyperplasia on progressive stenosis, and the subsequent thrombosis of hemodialysis fistula. A cross-sectional and 2-yr prospective pilot study was performed in 30 nondiabetic hemodialysis patients with primary arteriovenous fistula. Venous dialysis pressure, urea recirculation, color Doppler sonography, and angiography were used to monitor vascular access patency. Eleven patients (37%) developed a progressive stenosis in the venous circuit, which was complicated by thrombosis in three patients. Compared with the patients without fistula dysfunction, these patients had higher serum levels of monocyte chemoattractant protein-1 and interleukin-6, two cytokines that regulate the proliferation of vascular smooth muscle cells, which is the key mechanism in the pathogenesis of fistula stenosis. In addition, they had hyperinsulinemia, hyperlipidemia, and increased plasma levels of two hemostasis-derived risk factors for thrombosis: plasminogen activator inhibitor type 1 and factor VII. Monocyte chemoattractant protein-1, interleukin-6, plasminogen activator inhibitor type 1, factor VII, triglycerides, and the ratios for cholesterol/HDL-cholesterol, apolipoprotein (apo) A-I/ apo C-III, apo A-I/apo B, and glucose/insulin were independent predictors of fistula dysfunction. This study demonstrates the influece of cytokines, hemostasis-derived vascular risk factor, hyperinsullnemia, and abnormallties of lipids and apolipoproteins on primary fistula survival. The assessment of these factors might be useful for the identification of the patients at risk of fistula stenosis and thrombosis.

Do reduced insulin sensitivity and dyslipidemia exist in borderline hypertensive patients?

To evaluate the relationship between insulin resistance, dyslipidemia, and blood pressure (BP), we measured BP, blood glucose, plasma insulin (INS) levels, total cholesterol (T-ch), and triglyceride after an overnight fast in 454 Japanese young, nonobese, nondiabetic factory workers, including 226 normotensive (NT), 120 borderline hypertensive (BHT), and 108 essential hypertensive (EHT) subjects. Age and body mass index were strictly matched among the three groups. Fasting INS and T-ch were greater in BHT > EHT > NT (BHT v NT, P < .05; EHT v NT, P < .05). We also recognized significantly positive correlations between T-ch and mean BP (R = 0.39, P = .021), and between fasting INS and mean BP (r = 0.56, P = .013). These results suggest that insulin resistance and dyslipidemia are associated with hypertension in its early stage.