Is insulin or its precursor independently associated with hypertension? An epidemiological study in Japanese-Brazilians.

Japanese individuals living outside Japan are more susceptible to chronic diseases included in the insulin resistance syndrome. Hyperinsulinemia and hypertension are associated, but large studies adjusting for confounders are still required. The present evaluated if insulin (I) or proinsulin (PI) was associated with hypertension after adjustment for other risk factors, in first (n=238) and second (n=292) generation Japanese-Brazilians, aged 40 to 79 years, living in a developed city in Brazil. Blood pressure (BP) was measured by random-zero sphygmomanometry. People with mean systolic/diastolic BP >140/90 mm Hg or taking antihypertensive drugs were considered hypertensive. Diagnosis of diabetes was based on results of an oral glucose tolerance test using WHO criteria. I and PI after fasting and 2 hours after glucose load were determined by specific immunofluorimetric assays. The first generation was older than the second (65.6+/-9.2 versus 53.6+/-8.4 years, P<.01) and male/female ratios were 1.14 and 0.87, respectively. The age-adjusted prevalence of hypertension was 29.2% with no difference between sexes or generations. Higher body mass index (25.2+/-4.3 versus 23.8+/-3.3 kg/m2), waist-to-hip ratio (0.939+/-0.067 versus 0.919+/-0.073), plasma glucose (6.3+/-2.3 versus 5.6+/-1.8 mmol/L), cholesterol (5.74+/-1.19 versus 5.48+/-1.08 mmol/L), and creatinine (74+/-26 versus 83+/-36 micromol/L) were found among the hypertensives (P<.05). Univariate analyses showed associations of obesity, diabetes, and dyslipidemia with hypertension. Logistic regression analyses demonstrated that 2-hour I (OR, 1.22; 95% CI, 1.02 to 1.46) and fasting PI (OR, 1.14; 95% CI, 1.00 to 1.31) remained significantly associated with hypertension, after adjustment for age, sex, generation, family history of hypertension, smoking habits, waist-to-hip ratio, serum creatinine, glucose intolerance, and dyslipidemia. Japanese-Brazilians have a higher prevalence of hypertension than the general population in Brazil. High levels of 2-hour I, seen in hypertensives, may be interpreted as independent risk factors for hypertension in this population. Our findings suggest that fasting PI should be useful, in addition to insulin, to assess risk factors for hypertension in epidemiological studies.

Disturbances of glucose and lipid metabolism in first and second generation Japanese-Brazilians. Japanese-Brazilian Diabetes Study Group.

Increased prevalence of self-reported NIDDM in Japanese-Brazilians was reported when compared to Japan. This study aimed at determining the prevalence of NIDDM and IGT in Japanese-Brazilians living in the city of Bauru, São Paulo, Brazil. The impact of western environment on the frequency of obesity, dyslipidemia and hypertension was investigated. All Issei (first generation; n = 238) and a random sample of Nisei (second generation; n = 292), aged 40-79 years, were selected for clinical examination and OGTT (WHO criteria). Age-adjusted prevalence of NIDDM did not differ between men and women for Issei (12.4 vs. 11.6%, respectively), but it became different for Nisei (21.7 vs. 11.4%, P < 0.03) due to an increased rate among men. Increased IGT prevalence was also observed between Issei and Nisei men (8.5 vs. 19.3%, P < 0.03). Issei women had a higher IGT rate than Issei men (27. 3 vs. 8.5%, P < 0.0005). Body mass index (BMI) was higher in the second generation (24.1 +/- 3.6 vs. 23.3 +/- 3.1 kg/m2, P < 0.00005) and also the frequency of obesity, defined as BMI > 25 kg/m2. Comparison of waist/hip ratio by gender showed that only among women, Nisei had lower ratio than Issei (0.90 vs. 0.88, P < 0.05). Nisei had a lower total and LDL-cholesterol than Issei but triglyceride and HDL-cholesterol did not differ. Nisei women (younger than the Issei) had lower triglyceride and total cholesterol. This pattern was not seen between the two generations of men. Considering the mean blood pressure values, Issei and Nisei groups with normal glucose tolerance were not hypertensive. Systolic blood pressure was lower in Nisei and the inverse was found concerning diastolic levels. NIDDM prevalence in Japanese-Brazilians is higher than in Japan and in the general Brazilian population. Besides environment, genetic factors may confer susceptibility to NIDDM when they are exposed to a western environment. Before developing glucose intolerance, disturbances of lipid profile and blood pressure could be detected. Nisei may be more affected due to a longer exposure to an unfavorable environment and these changes seem to occur earlier among men than women.

Self-reported prevalence of non-insulin-dependent diabetes mellitus in the 1st (Issei) and 2nd (Nisei) generation of Japanese-Brazilians over 40 years of age.

The immigration of Japanese people to Brazil began in 1908 with two major waves, from 1925 to 1940 and from 1952 to the 1960s. Brazil has the largest population (about 1,288,000) of Japanese origin outside Japan with varying age groups. A mortality study revealed that diabetes as an underlying cause of death was higher in the first-generation Japanese than in Japan (3.4 vs. 1.9 per 100,000 for men, and 7.2 vs. 1.9 for women). The self-reported prevalences of known diabetes in subjects aged 40 years or older were obtained by questionnaires from three sources. In six Japanese cultural associations in Säo Paulo city, the prevalences were 9.7% and 6.9% for the first generation (mean age 61.5 years) and for the second generation (mean age 40.0 years), respectively. Age-adjusted prevalences, according to the Brazilian population in the 1980 national census, were 6.9% and 8.1% for the first and second generations. According to a study carried out as a part of a socioeconomic census of the Japanese population in Brazil, the prevalences of diabetes were 7.4% and 5.2%, and the age-adjusted prevalences were 5.3% and 5.8% in the first and second generations, respectively. Another study carried out for employees of a bank, owned by Japanese-Brazilian community members, revealed crude prevalences of diabetes in the first and second generations of 7.1% and 4.2%, and age-adjusted prevalences of 7.3% and 8.2%, respectively. These data indicate an increased prevalence of diabetes in this population compared to Japan, suggesting the importance of environmental factors in the pathogenesis of diabetes.

Proinsulin and insulin levels according to glucose tolerance among Japanese-Brazilians, aged 40-79 years. Japanese-Brazilian Diabetes Study Group.

This study of the Japanese-Brazilians living in Bauru, Sao Paulo, Brazil, aimed at determining the prevalence of DM in the first (Issei) and second (Nisei) generations, according to WHO criteria. Insulin and proinsulin were determined by new immunofluorimetric assays (IMFA), that measure true insulin and intact proinsulin, at fasting and 2 h after glucose load. The data showed a very scattered distribution, so only medians are shown and no statistical testing applied. There was a tendency for higher proinsulin levels in the diabetic groups. The highest fasting proinsulin levels were seen in the diabetic patients, either obese or non-obese. The post-load insulin levels were higher in diabetic and IGT individuals, compared to normals. Both generations showed a distinct behaviour for the obese and non-obese groups, and no major differences were observed between generations. This population seems to be sensitive to environmental changes, since the obese groups showed the higher levels of proinsulin and insulin. In the evaluation of the role of the environmental factors in the pathogenesis of DM, proinsulin and insulin levels could act as early markers of pancreatic dysfunctions.

Insulin resistance in septic rats--a study by the euglycemic clamp technique.

Male Wistar rats weighing 250 +/- 30g were made septic by cecum ligation and perforation. Peripheral and hepatic sensitivity to insulin was assessed by the euglycemic glucose clamp technique with simultaneous [3H]glucose infusion. Hepatic glucose output was not suppressed by the insulin infusion in the septic rats in contrast with the controls. Glucose utilization by the peripheral tissues was not significantly different between the septic and control rats. Counterregulatory hormone levels were higher in the septic group. Our data suggest that the liver is the site of insulin resistance in the septic state.

[Diabetes as primary or associated cause of death in the state of São Paulo, Brazil, 1992]. / Diabetes como causa básica ou associada de morte no estado de São Paulo, Brazil, 1992.

INTRODUCTION: Analysis of mortality data are usually performed with reference to the underlying cause of death. The importance of diabetes as a cause of death is always underestimated, because diabetics generally die from chronic complications of the disease, these being considered as the underlying cause of the death. To attenuate this problem, mortality data should be analyzed on the basis of all the causes listed on the death certificate. Frequency of references to diabetes on death certificates and the principal associated causes were evaluated as a contribution to the solution of this problem. METHODOLOGY: Specific death rates and proportional mortality by diabetes, as underlying or associated cause, were calculated on the basis of information derived from death certificates by the ACME program (Automated Classification of Medical Entities), for the State of S. Paulo, in 1992. RESULTS AND CONCLUSIONS: Of a total of 202,141 deaths, diabetes was mentioned in 13,786 (6.8%) and as being the underlying cause in 5,305(2.6%). The proportion was higher for women than men (10.1 vs. 4.6% as mentioned, and 6.1 vs 2.9% as underlying cause). Among deaths with a mention of diabetes on the certificate, the main underlying causes were: diabetes (38.5%), cardiovascular (37.2%) and respiratory (8.5%) diseases, and neoplasias (4.8%). When diabetes was the underlying cause, the main associated causes were: cardiovascular (42.2%), respiratory (10.7%) and genitourinary (10.1%) diseases. When diabetes was an associated cause, the main underlying causes were: cardiovascular (60.5%) and respiratory (13.8%) diseases, and neoplasias (7.9%). In spite of the limitation of the data from death certificates, it is possible to observe the importance of diabetes as cause of death, reflecting its magnitude as a health problem. Also, the analysis by multiple causes of deaths gives an idea of the morbidity profile associated with diabetes at the time of death, showing the importance of the group of cardiovascular diseases.

Variation in glucose tolerance with ambient temperature.

Ambient temperature may affect venous glucose concentration after glucose tolerance tests. We analysed 1030 standardised 75 g tests. Although mean fasting values did not differ, post-load values did: adjusted mean 2 h glucose concentration was 1.03 mmol/L lower at lower (5-14 degrees C) than at higher (25-31 degrees C) temperatures (p < 0.001). The occurrence of abnormal glucose tolerance doubled on warmer days. The diagnostic accuracy of the glucose tolerance test showed clinically significant temperature-associated variation. These variations, if confirmed, call for temperature standardisation during glucose tolerance testing and/or alternative strategies for use when standardisation is not feasible.