[Diabetes as primary or associated cause of death in the state of 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.

[Increase in mortality associated with the presence of diabetes mellitus in Japanese-Brazilians]

OBJECTIVE

As part of a study involving Japanese migrants, living in a developed city in the state of S. Paulo, Southeastern Brazil, a four-year experience of mortality among diabetic and non-diabetic subjects is described and their respective death rates are compared. In 1993, a cohort of 530 Japanese-Brazilians (236 issei or 1st generation and 294 nisei or 2nd generation) of both sexes, aged 40 from to 79 years old, were identified.

RESEARCH DESIGN AND METHOD

At that time, 91 (17%) were classified as non-insulin-dependent diabetic subjects (NIDDM), 90 (17%) with impaired glucose tolerance (IGT) and 349 (66%) as normal, according to WHO criteria. In 1996, families were questioned with a view detecting the deaths which had occurred among the subjects previously studied. This information, in addition to that from death certificates was used to record the date and the causes of death. Mortality rates for all causes and for specific causes (circulatory and renal diseases) were obtained for the three groups of subjects, by glucose tolerance status. Proportional hazard regression models were used to compare the mortality rates, adjusted for several covariables (gender, age, generation, hypertension, dyslipidemia, obesity and serum creatinine).

RESULTS AND CONCLUSIONS

Crude mortality rate ratios for all causes and specific causes, for NIDDM, and normal subjects were 2.95 (95% CI: 1.10-7.62) and 4.57 (95% CI: 1.31-16.48), respectively. No difference was observed between the crude mortality rate ratio for IGT and normal subjects. After simultaneous adjustments for the covariates, higher mortality rates for specific causes were observed among NIDDM than in the normal subjects (mortality rates ratio: 3.86; 95% CI: 1.11-13.38). These results in Japanese-Brazilians are consistent with previous reports of increased mortality in other diabetic subjects, thus confirming the adverse effect of this metabolic disturbance on mortality among diabetic subjects.

[Comparison of 5 methods to estimate the prevalence of diabetes mellitus in population-based studies]

To aid in the search for more practical and reliable methods for use in population-based studies of diabetes mellitus, this article compares five ways of estimating prevalence rates. The analysis was performed on secondary data from a cross-sectional study of a cluster sample of the adult population in nine state capitals in Brazil. The original study was carried out from 1986 to 1988. The 21,846 participants were classified as diabetic or not diabetic by five different methods: household questionnaires administered to the entire sample population (M1); individual questionnaires administered to the selected population (M2); measurement of fasting glucose levels in capillary blood, with levels > or = 120 mg/dL as the cutoff (M3); individual questionnaire and fasting capillary blood glucose > or = 120 mg/dL (M4); and individual questionnaire plus fasting capillary blood glucose > or = 120 mg/dL and capillary glucose 2 hours after oral glucose loading > or = 200 mg/dL (M5). Agreement between the methods was determined by comparison of the rates obtained and use of the kappa coefficient. The age-adjusted prevalence rates of diabetes varied according to the method used. Values obtained with M1 were lower than those indicated by M2; M3 values were higher than M2 values, except in the age group 60-69 years; and with M5 the rates were higher than with M4, except among persons 30-39 years old. With regard to the age-adjusted rates found by the various methods, M1 detected 84% of the M2 estimate, M2 detected 91% of the M3, M3 detected 70% of the M4, and M4 detected 86% of the M5. Previously diagnosed diabetes cases accounted for 64% and 55% of the totals estimated by M4 and M5, respectively. Kappa values were at least 0.70 for M1 compared against M2, M1 against M4, M2 against M4, and M3 against M4. Based on the results of this study, it was concluded that the questionnaires used in M1 and M2 constituted appropriate methods for detecting previously diagnosed cases of diabetes mellitus, and their use is recommended for the purposes of health services planning or evaluation. Fasting glucose measurement (M3) as the sole method did not show a significant advantage over the individual questionnaire (M2). Of the combined or multiple methods, fasting glucose together with the individual questionnaire (M4) was efficient in comparison to M5, which incorporated measurement of blood glucose 2 hours after oral glucose ingestion.

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.

Diabetes in Japanese-Brazilians--influence of the acculturation process

Epidemiologic studies of migrant populations provide very promising clues towards understanding the roles of genetics and environmental factors in the etiology of diabetes mellitus. Populations of Japanese ancestry are of particular interest due to marked differences in prevalence rates of non-insulin dependent diabetes (NIDDM) when comparing those living in Japan with those who migrated to western countries. Brazil offers very favorable conditions of the study of diabetes in the Japanese origin population. Presently, Brazil has the largest population of Japanese ancestry outside Japan. A cross-sectional study comparing first (Issei) and second (Nisei) generations of Japanese-Brazilians living in the city of Bauru, in the industrialized state of São Paulo, southeast of Brazil, was carried out between May and November 1993. The study sample consisted of all first generation (127 men and 111 women) and a random sample of second generation (136 men and 156 women) aged 40-79 years. Results show that: 1--The prevalence of diabetes in Japanese Brazilians (12.8 and 16.2% for first and second generations) are higher than the rates reported for Japan at comparable age-groups. 2--Comparing generations, the age-adjusted prevalence of diabetes was higher in the second generation only for men (men: 12.4 vs. 21.7%; women: 11.6 vs. 11.4%). 3--Obesity was more prevalent in the second generation among men (Men: 34.6 vs. 45.7% women, 39.6 vs. 40.8%).

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.

[Prevalence of dental caries in children from 0 to 6 years old attending nursery: the influence of socioeconomic factors]

Oral health condition in samples of children from zero to six years old, examined in day nurseries for children from Bauru and S. Paulo County (Brazil) by the caries indicator in primary dentition-dmfs, is assessed. The first group did not receive oral health care where any as the second group received the standard oral care provided by the institution. Variables related to way of life and their relationship to the presence of caries were evaluated. Multiple regression analysis showed a statistically significant association of age and frequency of dental visits with the prevalence of dental caries (p < 0.05). The data also showed that 23.3% of the children from Bauru, and 9.3% of those from S. Paulo were free of caries, numbers that are very far from the 50% proposed by WHO for the year 2000. The overall prevalence of dental caries was greater for the Bauru group than for the S. Paulo group; however, statistical significance was only found in the 3-4 age-group (p < 0.05). Sex differences in the occurrence of dental caries were not statistically significant.

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.

The prevalence of diabetes in Rio de Janeiro, Brazil. The Cooperative Group for the Study of Diabetes Prevalence in Rio De Janeiro

OBJECTIVE

To assess the prevalence of diabetes and impaired glucose tolerance (IGT) in the adult population of Rio de Janeiro, a two-stage cross-sectional survey was carried out in a random sample of 2,051 individuals aged 30-69 years from Rio de Janeiro city in Brazil.

RESEARCH DESIGN AND METHODS

Subjects were first screened by fasting capillary glycemia (FCG). All individuals who screened positive (FCG > 5.6 mmol/l) and every sixth consecutive person who screened negative (FCG < 5.6 mmol/l) were subjected to a 75-g glucose load. Diagnoses of diabetes and IGT were based on World Health Organization criteria.

RESULTS

Results from every sixth individual who screened negative were extrapolated to all individuals who screened negative after adjustment for some potential bias in the subsample. Age-adjusted prevalence rates for diabetes and IGT were 7.1 and 9.0%, respectively. The rates were higher (P < 0.01) among women than among men (8.7 vs. 5.2% for diabetes and 11.7 vs. 5.8% for IGT), among obese individuals than among nonobese individuals (7.9 vs. 6.2% for diabetes and 11.4 vs. 7.3% for IGT), and among those with family history of diabetes than among those without family history of diabetes (12.4 vs. 4.8% for diabetes and 13.8 vs. 6.7% for IGT). The rates for diabetes and IGT increased with age, being 1.7 and 4.5%, respectively, for the age-group of 30-39 years, 3.9 and 8.5% for the age-group of 40-49 years, 13.6 and 13% for the age-group of 50-59 years, and 17.3 and 15.3% for the age-group of 60-69 years (P < 0.01). The prevalence of diabetes was higher among individuals with low educational levels than among those with high educational levels (7.3 vs 4.2%). For IGT, the rates increased from the group with intermediate level of education (8.3%) to the low- (11.3%) and high-education group (12.6%). Differences in the rates for whites and non-whites (6.9 vs. 7.1% for diabetes and 8.8 vs. 9.6% for IGT) were not statistically significant. Among those with confirmed diabetes in the survey, 27.6% did not know of their diabetic condition. Among previously diagnosed diabetes (self-reported diabetes), 19.5% were not being treated, 31.8% were on diet only, 40.7% were on oral hypoglycemic drugs, and 8.0% were on insulin. Self-reported prevalence of diabetes was 0.1% for the population < 30 years of age, 4.3% for the 30-69 year old age-group, and 16.6% for those > 70 years of age.

CONCLUSIONS

The numbers found for Rio de Janeiro are similar to those for more developed countries and lead us to conclude that the impact of diabetes on public health is the same as in those countries where this disease is considered an important health problem.

The ROC curve in the evaluation of fasting capillary blood glucose as a screening test for diabetes and IGT

OBJECTIVE

To assess the performance of different cutoff points of fasting capillary glycemia (FCG) in the diagnosis of diabetes and impaired glucose tolerance (IGT) using the receiver operating characteristics (ROC) curve approach.

RESEARCH DESIGN AND METHODS

This study included a sample of 4,019 subjects without a previous history of diabetes who were recruited for a confirmatory 2-h post-glucose challenge capillary glycemia from a larger sample of 21,847 individuals screened with FCG. The sensitivity and the specificity of FCG as a screening test were analyzed in the cutoff range 3.9-8.9 mmol/l, and the corresponding ROC curves were plotted to assess the performance of the test.

RESULTS

The screening test performance was better for diabetes than for IGT in the full range of cutoff points studied. Sensitivities ranged between 37.9 and 97.1% for diabetes and 1.8 and 94.4% for IGT; the areas under the ROC curves were 0.91 +/- 0.01 and 0.75 +/- 0.01, respectively. The cutoffs showing the best equilibrium between sensitivity and specificity approached 5.6 and 5.0 mmol/l for diabetes and IGT, respectively. Factors such as age, color, and family history of diabetes can affect the screening test performance.

CONCLUSIONS

ROC curves can provide useful information toward improving the usefulness of FCG as a screening test for abnormalities of glucose tolerance.

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.

Population-based incidence of IDDM in the state of São Paulo, Brazil

OBJECTIVE

To study the incidence of IDDM among children, infants to 14 yr of age, in the state of São Paulo, Brazil, 1987-1991.

RESEARCH DESIGN AND METHODS

A prospective population-based register was established, using physician reports of newly diagnosed IDDM patients < 15 yr of age as the primary source of case identification and school surveys as the main secondary source. Data were collected according to the methods recommended by the Diabetes Epidemiology Research International group.

RESULTS

Case ascertainment was estimated at 95.0, 92.8, and 98.8% complete for each of the three cities studied. The average annual IDDM incidence was 7.6/100,000 inhabitants (95% confidence interval, 5.6-9.7). We found a higher incidence rate in girls than boys.

CONCLUSIONS

The incidence of childhood IDDM in a tropical region in South America (São Paulo, Brazil) is in the middle incidence range observed in developed countries throughout the world. Increased incidence of IDDM in girls compared with boys will be tested by the ongoing Brazilian incidence study being developed in 18 other centers across the country.

Multicenter study of the prevalence of diabetes mellitus and impaired glucose tolerance in the urban Brazilian population aged 30-69 yr. The Brazilian Cooperative Group on the Study of Diabetes Prevalence

OBJECTIVE

To assess the prevalence of diabetes and IGT in the urban adult Brazilian population.

RESEARCH DESIGN AND METHODS

We used a two-stage, multicenter, cross-sectional survey in a random sample of 21,847 individuals aged 30-69 yr from nine large cities. Subjects were first screened by FCG. All positive screenees (FCG > or = 5.6 mM/L) and every sixth consecutive negative screenee were administered a 75 g OGTT and classified as diabetic, IGT, or normal (nondiabetic) according to WHO recommendations. OGTT findings from the negative screenees were extrapolated to all negative screenees after adjustments for potential biases.

RESULTS

The overall rates were 7.6 and 7.8% for diabetes and IGT, respectively. Men (7.5%) and women (7.6%) had similar rates of diabetes. Similar rates resulted with whites (7.8%) and nonwhites (7.3%). Diabetes prevalence increased from 2.7% in the 30-39-yr age-group to 17.4% in the 60-69-yr age-group. Diabetes was more prevalent among less educated people, but this difference disappeared after adjusting for age. Family history of diabetes was associated with a twofold increase in diabetes prevalence (12.5 vs. 5.8%); the same increase occurred with obesity (11.6 vs. 5.2%). Undiagnosed diabetes accounted for 46% of the total prevalence. Among previously diagnosed cases, 22.3% were not under treatment, 7.9% were on insulin, 40.7% were on oral agents, and 29.1% were on dietary treatment only. Self-reported diabetes prevalence was 0.1, 3.2, and 11.6% in the age groups < 30, 30-69, and > 70 yr, respectively.

CONCLUSIONS

The prevalence of diabetes in Brazil is comparable with that of more developed countries, where it is considered a major health problem.

Blood pressure in four remote populations in the INTERSALT Study

Four remote population samples (Yanomamo and Xingu Indians of Brazil and rural populations in Kenya and Papua New Guinea) had the lowest average blood pressures among all 52 populations studied in INTERSALT, an international cooperative investigation of electrolytes and blood pressure. Average systolic blood pressure was 103 versus 120 mm Hg in the remaining INTERSALT centers; diastolic blood pressure in these four population samples averaged 63 versus 74 mm Hg in the 48 other centers. There was little or no upward slope of blood pressure with age; hypertension was present in only 5% of the rural Kenyan sample and virtually absent in the other three centers. Also in marked contrast with the rest of the centers was level of daily salt intake, as estimated by 24-hour urinary sodium excretion. Median salt intake ranged from under 1 g to 3 g daily versus more than 9 g in the rest of INTERSALT populations. Average body weight was also low in these four centers, with no or low average alcohol intake, again unlike the other centers. The association within these four centers between the above variables and blood pressure was low, possibly reflecting their limited variability. While several other INTERSALT centers also had low average body weight or low prevalence of alcohol drinking, when this was accompanied by much higher salt intake (7-12 g salt or 120-210 mmol sodium daily), hypertension prevalence ranged from 8% to 19%. These findings confirm previous reports that in populations with a low salt intake, there is little or no hypertension or rise of blood pressure with age.(ABSTRACT TRUNCATED AT 250 WORDS)

Coffee consumption, diet, and lipids

Recent reports suggest that coffee consumption is associated with increased serum cholesterol and triglyceride concentrations. The authors examined the association between serum lipids and coffee consumption and other caffeinated beverages as part of a population-based study of 1,228 women and 923 men, aged 25-64 years, in San Antonio, Texas, studied between October 1979 and November 1982. The study confirmed a positive relationship between coffee consumption and both total and low density lipoprotein cholesterol in both sexes which persisted after adjustment for age, ethnicity, obesity, cigarette smoking, and alcohol consumption. Neither tea nor cola consumption was associated with changes in serum lipids, suggesting that caffeine alone does not exert a direct effect on lipid levels. The possibility was examined that the coffee-cholesterol relationship might be due to a more atherogenic diet consumed by heavy coffee drinkers. In men, per cent calories from both total and saturated fat and dietary cholesterol intake increased with increased coffee consumption. Similar trends were not observed in women, however. The positive relationship between coffee and cholesterol may therefore be due to confounding effects of other aspects of the diet.

Prevalence, detection, and control of hypertension in a biethnic community. The San Antonio Heart Study

A survey was carried out on a random sample of 1,288 Mexican Americans and 929 Anglos living in three socially distinct neighborhoods in San Antonio, Texas. Hypertension was defined as diastolic blood pressure greater than or equal to 95 mmHg or currently taking antihypertensive medication. Overall age-adjusted prevalence rates of hypertension were similar for Mexican-American and Anglo men (10.0 and 9.8%, respectively); for women, the Mexican-American rate was slightly lower than that for Anglos (7.8 and 9.7%, respectively). After adjustment for obesity differences, Mexican Americans have a tendency toward lower hypertension rates than Anglos of the same socioeconomic level. Only among women was a decline in the prevalence of hypertension with increasing socioeconomic status observed. Mexican Americans have a higher proportion of newly diagnosed hypertension, and, among previously diagnosed cases, a lower proportion are on antihypertensive medication than Anglos. The rates of hypertension control found in this survey are among the highest reported in the United States at the community level. Despite this, Mexican Americans still lag somewhat behind Anglos of the same socioeconomic level in awareness, treatment, and degree of hypertension control, suggesting the possibility of sociocultural barriers to adequate medical care.

Evidence of bimodality of two hour plasma glucose concentrations in Mexican Americans: results from the San Antonio Heart study

Evidence for bimodality in the distribution of two hour post oral glucose challenge plasma glucose concentrations has come previously primarily from native American and Pacific Island populations having high non-insulin dependent diabetes mellitus (NIDDM) prevalence. Because the National Diabetes Data Group (NDDG) criteria for diagnosing NIDDM rely in part upon the assumption of bimodality, it is important to determine the generality of this phenomenon. We looked for bimodality among Mexican Americans in San Antonio, a population having greater than 50% Caucasian admixture. By fitting both a single normal distribution model and a mixture model of two normal distributions, for each age decade, we found that the mixture model was preferred to the single normal model (p less than 0.001) and that this model fit the data well. The proportion in the upper component (hyperglycemics) increased with each successive age decade. The minimum misclassification cutpoints decreased with age, but all were higher than the 200 mg/dl cutpoint recommended by the NDDG. Use of the NDDG cutpoint, however, improved sensitivity with only a minimal deterioration of specificity. Our findings further generalize the bimodality phenomenon and support the NDDG criteria.

Sex difference in the effects of sociocultural status on diabetes and cardiovascular risk factors in Mexican Americans. The San Antonio Heart Study

The authors postulated that as Mexican Americans became more affluent and/or acculturated to "mainstream" United States life-style they would progressively lose their "obesity-related" pattern of cardiovascular risk factors which were defined as: obesity, diabetes, hypertriglyceridemia and low levels of high density lipoprotein cholesterol. This hypothesis was tested in 1979-1982 in the San Antonio Heart Study, a population-based study on 1,288 Mexican Americans and 929 Anglos living in three San Antonio neighborhoods: a low-income barrio, a middle-income transitional neighborhood, and a high-income suburb. The study population comprised 25-65-year-old men and nonpregnant women. In Mexican American women, all of the "obesity-related" risk factors fell sharply with rising socioeconomic status. In Mexican American men, by contrast, diabetes was the only "obesity-related" risk factor which fell with rising socioeconomic status. Moreover, it fell less steeply, there being an approximately twofold difference in diabetes prevalence between the barrio and the suburbs in men compared to a fourfold difference in women. Also, total and low density lipoprotein cholesterol rose with rising socioeconomic status in Mexican American men, but not in Mexican American women. "Obesity-related" risk factors were generally higher in Mexican Americans of both sexes than in their Anglo neighbors who were of similar socioeconomic status. These results suggest that cultural factors exert a stronger influence on diabetes and cardiovascular risk factors in Mexican Americans than do purely socioeconomic factors.

Evaluation of three potential screening tests for diabetes mellitus in a biethnic population

We tested the ability of three potential screening tests for diabetes (fasting plasma glucose value greater than or equal to 140 mg/dl, 1-h postglucose (PG) load value greater than or equal to 200 mg/dl, and 2-h PG value greater than or equal to 200 mg/dl) to detect non-insulin-dependent diabetes in 130 diabetic Mexican Americans (MAs) and 50 diabetic Anglo Americans (AA) using the National Diabetes Data Group criteria as the standard. The sensitivity of the fasting plasma glucose (FPG) cutpoint in detecting diabetes was low in both AAs (36.0%) and MAs (59.3%) and was related to the age-adjusted prevalence rates of diabetes in the two ethnic groups (AAs, 4.9%; MAs, 10.9%). The 2-h PG load cutpoint had good sensitivity (greater than 93%) and specificity (greater than 99%) in both ethnic groups. The ethnic difference in the sensitivity of the FPG cutpoint appeared to be related to the greater hyperglycemia of diabetic MAs compared with diabetic AAs. Nearly 30% of diabetic MAs had FPG values greater than or equal to 200 mg/dl as contrasted with only 10% of diabetic AAs. The difference in severity of hyperglycemia between the ethnic groups appears to be unrelated to ethnic differences in adiposity, pharmacologic treatment, or delay in diagnosis, although longer disease duration in MAs may explain part of the difference.