Prospective assessment of metabolic control in diabetes mellitus: the complications question.
Explore the source record for details and available documents.
Adult↗
Biomedical subjects
S M Haffner
Publications and source records attributed to S M Haffner.
Increased insulin concentrations in nondiabetic offspring of diabetic parents.
Insulin resistance is thought by many to be the primary defect that results in non-insulin-dependent diabetes mellitus (NIDDM). An implication of this theory is that prediabetic persons have higher serum insulin levels than normal subjects. We assessed serum insulin concentrations in a cohort of 1497 nondiabetic Mexican Americans, a population at high risk for NIDDM, according to whether their parents or siblings had diabetes. It was assumed that prediabetic persons would be more likely to have strong family histories of diabetes. We found a stepwise increase in fasting insulin levels in nondiabetics with neither, one, or both parents with diabetes (69.8, 77.8, and 94.6 pmol per liter, respectively; P = 0.002). Similar results were observed for insulin sum (the total of insulin concentrations in the fasting state and at 30, 60, and 120 minutes after a 75-g oral glucose load). The differences in insulin sums according to family history remained statistically significant in analyses of covariance, which controlled for variations in body-mass index, body-fat distribution, and level of blood glucose. Subjects without diabetes who had a diabetic sibling had higher fasting concentrations of insulin than subjects without a diabetic sibling (83.2 vs. 69.6 pmol per liter), but the difference was not statistically significant. We conclude that prediabetic persons, who would be expected to be more numerous in kindreds with progressively stronger family histories of diabetes, have hyperinsulinemia. This supports the insulin-resistance hypothesis.
Adult↗
The relationship of sex hormones to hyperinsulinemia and hyperglycemia.
Mexican-Americans, a high-risk population for non-insulin-dependent diabetes mellitus (NIDDM), have been previously reported to have decreased levels of sex-hormone-binding globulin (SHBG). We measured total testosterone, total estradiol and SHBG, glucose and insulin in premenopausal women (58 Mexican-Americans and 38 non-Hispanic whites) as part of the San Antonio Heart Study, a population-based study of cardiovascular risk factors. Although total estradiol and total testosterone were, in general, not correlated with metabolic variables, SHBG was negatively correlated with glucose and insulin. After adjustment for body mass index (BMI), ratio of waist-to-hip circumference (WHR) and ratio of subscapular-to-triceps skinfold (Centrality Index), SHBG was still significantly correlated with insulin concentrations (P less than .001). Since Mexican-Americans were previously reported to be more hyperinsulinemic than non-Hispanic whites, we examined the effect of adjusting for SHBG on insulin levels in this small population. While unadjusted insulin concentrations in Mexican-Americans were higher than in non-Hispanic whites (354 microU/mL v 236 microU/mL, respectively, P = .009), adjustment for BMI, WHR, and centrality index reduced the ethnic difference in insulin levels considerably (P = .014). However, only after adjusting for SHBG as well, did the ethnic difference in insulin levels became nonsignificant. Our data suggest that alterations in sex hormones and SHBG in particular may be related to the hyperinsulinemia and the high rates of NIDDM in Mexican-Americans.
Adult↗
Hyperinsulinemia, upper body adiposity, and cardiovascular risk factors in non-diabetics.
Previous studies have suggested that hyperinsulinemia and upper body adiposity are each separately associated with elevated BP and triglyceride (TG) levels, and with lower high density lipoprotein (HDL) cholesterol levels. The joint effect of hyperinsulinemia and upper body adiposity on lipids, lipoproteins, and BP, however, has not been previously studied. We hypothesized that the effect of body fat distribution on cardiovascular risk factors might be mediated through hyperinsulinemia. We measured BP, lipids and lipoproteins, HDL subfractions, and insulin and glucose concentrations as part of the San Antonio Heart Study, a population-based study of diabetes and cardiovascular risk factors. Insulinemia and glycemia were assessed as the sum of the fasting, half-hour, one-hour, and two-hour insulin and glucose levels, respectively, measured during a standardized oral glucose tolerance test. Individuals who had diabetes according to National Diabetes Data Group criteria were excluded from the analyses. In univariate analyses, both hyperinsulinemia and waist-to-hip ratio (WHR), a measure of upper body adiposity, were positively associated with TG and negatively associated with total HDL and HDL2 cholesterol levels. However, when the effects of glycemia and insulinemia were controlled for by analysis of variance, WHR was no longer significantly related to TG levels. By contrast, WHR continued to be inversely related to total HDL and HDL2 cholesterol even after adjustment for glycemia and insulinemia. Hyperinsulinemia was only weakly related to HDL cholesterol. These results suggest that insulinemia and glycemia might mediate the effects of upper body adiposity on TG, although not on HDL and HDL2 cholesterol. Hyperinsulinemia was also positively associated with diastolic and systolic BP in men.
Adipose Tissue↗
Excess incidence of treatment of end-stage renal disease in Mexican Americans.
Mexican Americans are the second largest minority group in the United States (8.73 million people according to the 1980 US census) and are known to have an excess prevalence of obesity and non-insulin-dependent diabetes mellitus, but similar or lower rates of hypertension when compared with non-Hispanic whites. To our knowledge, no data are available on incidence of end-stage renal disease in this population. Using a data base from the Texas Kidney Health Program, a division of the Texas Department of Health, and the 1980 US census for the state of Texas, the authors calculated age-adjusted incidence of treatment of end-stage renal disease in Mexican Americans, non-Hispanic whites, and blacks for the years 1978-1984. Mexican Americans and blacks have an excess of treatment of end-stage renal disease (all etiologies combined) compared with non-Hispanic whites (incidence ratios of 3 and 4, respectively). For diabetes-related end-stage renal disease, Mexican Americans have an incidence ratio of 6, while blacks have an incidence ratio of 4 compared with non-Hispanic whites. For Mexican Americans, this excess is higher than would be expected on the basis of their underlying prevalence of diabetes. The incidence of hypertensive end-stage renal disease in Mexican Americans was 2.5 times higher than in non-Hispanic whites, which is higher than expected given the lack of excess in their underlying prevalence of hypertension. The high prevalence of diabetes in Mexican Americans explains some, but not all, of the excess of treatment of end-stage renal disease in this population.
Adult↗
Effects of acculturation and socioeconomic status on obesity and diabetes in Mexican Americans. The San Antonio Heart Study.
The authors hypothesized that increased socioeconomic status and acculturation of Mexican Americans to mainstream US society would be accompanied by a progressive lessening of obesity and non-insulin-dependent diabetes mellitus. This hypothesis was tested in 1979-1982 in the San Antonio Heart Study, a population-based study of 1,288 Mexican Americans and 929 non-Hispanic whites, aged 25-64 years, randomly selected from three San Antonio neighborhoods: a low-income barrio, a middle-income transitional neighborhood, and a high-income suburb. Socioeconomic status was assessed by the Duncan Socioeconomic Index, a global measure of socioeconomic status based on occupational prestige. Acculturation was assessed by three scales which measure functional integration with mainstream society, value placed on preserving Mexican cultural origin, and attitude toward traditional family structure and sex-role organization. In Mexican-American men, increased acculturation was accompanied by a statistically significant, linear decline in both obesity and diabetes, while socioeconomic status had no significant effect on either outcome. In Mexican-American women, on the other hand, increased acculturation and increased socioeconomic status were accompanied by statistically significant, linear declines in both outcomes. However, the effects of acculturation on obesity and diabetes prevalence in women were stronger than the effects of socioeconomic status. In women, obesity also appeared to be a more important mediator of the relation between socioeconomic status and diabetes than of the relation between acculturation and diabetes. The results of this study suggest that culturally mediated factors exert a more pervasive influence on obesity and diabetes in Mexican Americans than do socioeconomically mediated factors. The influence of socioeconomic status in women, however, cannot be ignored, particularly with regard to obesity.
Acculturation↗
Do anthropometric differences between Mexican Americans and non-Hispanic whites explain ethnic differences in metabolic variables?
Explore the source record for details and available documents.
Adipose Tissue↗
Diabetic retinopathy in Mexican Americans and non-Hispanic whites.
Mexican Americans (MAs) have a threefold greater prevalence of non-insulin-dependent diabetes mellitus (NIDDM) than non-Hispanic Whites (NHWs). Because MA diabetic subjects have greater hyperglycemia and an earlier age of onset than NHW diabetic subjects, we postulated that diabetic MAs might also have more severe diabetic retinopathy. Stereoscopic retinal photographs of the seven standard fields of each eye were taken in 257 MAs and 56 NHWs with NIDDM. The photographs were read by the University of Wisconsin Fundus Photographic Reading Center and graded with standardized criteria. The MAs had a nonsignificantly increased risk of retinopathy relative to the NHWs [odds ratio (OR) = 1.71; 95% confidence interval (Cl) = (0.93, 3.17)]. The risk of severe retinopathy (proliferative or preproliferative) relative to background or no retinopathy was significantly greater in MAs than in NHWs [OR = 2.37; 95% Cl = (1.04, 5.39)]. After control by logistic regression for duration of disease, severity of hyperglycemia, age, and systolic blood pressure, MAs still had an increased risk of severe retinopathy relative to NHWs [OR = 3.18; 95% Cl = (1.32, 7.66)]. Severe retinopathy was related to duration of disease, hyperglycemia, and insulin therapy in both ethnic groups. Previously diagnosed MA diabetic subjects also had an increased prevalence of any retinopathy [OR = 2.39; 95% Cl = (1.63, 3.50)] and severe retinopathy [OR = 3.21; 95% Cl = (2.24, 4.59)] relative to previously diagnosed White diabetic subjects (n = 896) from Wisconsin.(ABSTRACT TRUNCATED AT 250 WORDS)
Adult↗
A saturated fat/cholesterol avoidance scale: sex and ethnic differences in a biethnic population.
Avoidance of saturated fat and cholesterol by 1,210 Mexican Americans and 866 non-Hispanic whites was assessed as part of a population-based survey of diabetes and cardiovascular risk factors. Participants ranged in age from 25 to 64 years and resided in three socioeconomically distinct neighborhoods of San Antonio, TX: low income, middle income, and upper income. A scale was constructed to assess the degree to which individuals avoided six dietary sources of saturated fat and cholesterol. Women of both ethnic groups were found to avoid saturated fat and cholesterol to a greater degree than men, scoring higher on five of the six components of the scale. Saturated fat/cholesterol avoidance increased significantly with increased socioeconomic status in both ethnic groups. Although there were no ethnic differences in overall saturated fat/cholesterol avoidance, more non-Hispanic whites recognized milk, eggs, and visible fat on meat as food sources to avoid. The scale described in this paper provides useful information about the specific food components recognized as dietary sources of saturated fat and cholesterol and helps identify those population groups that would benefit from nutrition education programs. Because of its simplicity and ease of administration, the scale may be a useful tool in epidemiological research.
Adult↗
The dyslipoproteinemia of anabolic steroid therapy: increase in hepatic triglyceride lipase precedes the decrease in high density lipoprotein2 cholesterol.
Administration of the androgenic anabolic steroid, stanozolol, is associated with decreased high density lipoprotein (HDL) cholesterol (primarily due to decreased HDL2 cholesterol) and increased levels of postheparin plasma hepatic triglyceride lipase (HTGL) activity. Since HTGL appears to play a role in HDL metabolism, we examined the temporal relationship between these changes. HDL cholesterol remained stable during the first two days of stanozolol administration, but decreased 14% (P less than .01) by the third day and 39% (P less than .01) by the seventh day of stanozolol. HDL2 cholesterol paralleled the total HDL cholesterol level and remained stable for the first two days, but decreased 22% (P less than .01) after three days and 71% (P less than .01) after seven days of stanozolol. In contrast, HTGL increased 62% (P less than .001) during the first day, 161% (P less than .001) with two days, 230% (P less than .001) with three days of stanozolol administration, and remained elevated thereafter. Thus, during stanozolol administration HTGL increased dramatically and clearly before any change in HDL or HDL2 cholesterol.
Adult↗
Coronary risk factors and clinical gallbladder disease: an approach to the prevention of gallstones?
We examined the relationship of "coronary" risk factors to clinical gallbladder disease prevalence in a cross-sectional survey. Persons with hypercholesterolemia, hypertriglyceridemia, or low high-density-lipoprotein cholesterol levels had elevated risks for clinical gallbladder disease. Smokers of 20 pack-years or more and infrequent users of alcohol had increased risks, as did persons with hypertension or diabetes mellitus. After adjusting for age, body mass index, ethnicity, and the coronary variables, relationships persisted for diabetes in women (OR = 1.8) and frequent alcohol use in men (OR = 0.3). The proportion of gallbladder disease related to all coronary risk factors was estimated to be 52 per cent.
Adult↗
Do upper-body and centralized adiposity measure different aspects of regional body-fat distribution? Relationship to non-insulin-dependent diabetes mellitus, lipids, and lipoproteins.
Both central and upper-body adiposity are associated with high rates of type II non-insulin-dependent diabetes mellitus (NIDDM), high triglyceride levels, and low high-density lipoprotein (HDL) cholesterol levels. Previous data have also suggested that central and upper-body adiposity are relatively uncorrelated and hence may measure different aspects of regional body fat distribution. We assessed body mass index (BMI), the ratio of subscapular-to-triceps skinfold (STR), the ratio of waist-to-hip circumference (WHR), lipids, lipoproteins, and glucose tolerance in 738 Mexican Americans (ages 25-64 yr), who participated in the San Antonio Heart Study, a population-based study of diabetes and cardiovascular risk factors. NIDDM was diagnosed according to National Diabetes Data Group criteria. In general, STR and WHR were associated with high NIDDM rates, low HDL cholesterol levels, and high triglyceride levels, although WHR was somewhat more predictive of these than STR. In females, BMI, WHR, and STR all made independent contributions to prediction of NIDDM and HDL cholesterol; in males, WHR and STR both made independent contributions to prediction of triglyceride levels. This suggests that both indices may measure different aspects of body-fat distribution. Investigators should consider measuring both of these indicators of body-fat distribution in studies of diabetes and other cardiovascular risk factors, although if only a single measure is feasible, WHR appears to be preferable.
Adipose Tissue↗
Hyperinsulinemia as a possible etiology for the high prevalence of non insulin dependent diabetes in Mexican Americans.
The prevalence of non-insulin dependent diabetes mellitus (NIDDM) is higher in Mexican Americans (MAs) than in non-Hispanic whites (NHWs) even after adjustment for the former's greater overall and more centralized adiposity. We previously have shown that MAs are more hyperinsulinemic than NHWs even after adjustment for body mass index (BMI), waist-to-hip ratio (WHR), subscapular-to-triceps skinfold ratio, and glucose tolerance. We now confirm these findings in much larger population (n = 1,182). Since hepatic extraction of insulin may be decreased with upper body adiposity, we also measured fasting and 2-hour C-peptides in a subset of subjects (n = 70). C-peptide concentrations were higher in MAs than in NHWs indicating that MAs have higher insulin secretion. We examined whether the increased insulin concentrations in MAs may be associated with a bimodal distribution of insulin concentrations in which the second or higher mode might represent pre-diabetics. No evidence of bimodality, however, was apparent. The effect of overall adiposity (BMI) and upper body adiposity was similar in both Mexican Americans (a high risk population for NIDDM) and non-Hispanic whites (a low risk population for NIDDM). These data indicate that, like other populations at high risk for NIDDM such as Pima Indians in the U.S. Southwest and Micronesians in the South Pacific, Mexican Americans have more hyperinsulinemia than can be accounted for by their adiposity and body fat distribution. Prolonged insulin secretion (secondary to increased insulin resistance), is one possible explanation for this phenomenon which could lead to islet cells decomposition and eventual clinical diabetes.
Adult↗
Hyperinsulinemia in a population at high risk for non-insulin-dependent diabetes mellitus.
The prevalence of non-insulin-dependent diabetes mellitus (NIDDM) is higher in Mexican Americans than in non-Hispanic white Americans, even after adjustment for the former's greater overall and more centralized adiposity. We postulated that this excess risk of NIDDM could be due to resistance to insulin. We performed oral glucose-tolerance tests with measurements of serum insulin concentrations in 225 Mexican Americans and 180 non-Hispanic whites without diabetes as part of the San Antonio Heart Study, a population-based study of risk factors for diabetes. Changes in serum insulin concentrations in response to the glucose challenge were quantified by the area under the serum insulin curve. Overall adiposity was characterized by body-mass index, and regional body-fat distribution by the ratio of subscapular to triceps skinfolds and the ratio of waist to hip circumference. After adjustment for these indicators of adiposity and also for differences in glucose tolerance, Mexican Americans were found to have significantly greater areas under the serum insulin curve than non-Hispanic whites. These data suggest that, like other populations at high risk for NIDDM such as Pima Indians and Micronesians, Mexican Americans have more hyperinsulinemia than can be accounted for by their adiposity.
Adult↗
Relationship of prevalence of non-insulin-dependent diabetes mellitus to Amerindian admixture in the Mexican Americans of San Antonio, Texas.
A genetic and epidemiological survey of non-insulin-dependent diabetes mellitus (NIDDM) was conducted among the Mexican Americans residing in three socioeconomically distinct areas of San Antonio, Texas: a low socioeconomic (SES) traditional area (barrio), a middle SES, ethnically balanced area (transitional), and a high SES, predominantly Anglo area (suburb). Seventeen polymorphic markers were used to relate the prevalences of NIDDM with the extent of Amerindian ancestry of 1,237 Mexican Americans of these three residential areas. While only the RH and haptoglobin loci showed evidence of association with NIDDM, an admixture analysis of the combined allele frequency data revealed a pattern of decreasing NIDDM prevalence with increasing socioeconomic status (as approximated by neighborhood of residence) and a parallel decrease in Amerindian ancestry. The rank-order correlation between NIDDM prevalence and Amerindian admixture is 0.943 (P less than .001) for the crude prevalence rate and 0.829 (P less than .02) for the age-adjusted rate. Nested gene diversity analysis revealed that the heterogeneity of allele frequencies is more pronounced when individuals were classified by their NIDDM disease status as compared to the classification by neighborhood. Estimation of Amerindian ancestry of each individual did not reveal any significant change in the shape of the distributions of individual admixture proportions in diabetics as compared to the controls. Nevertheless, the results suggest that genetic factors partially explain the differences in NIDDM prevalence observed between the Mexican American and Anglo populations in the southwestern United States.
Adult↗
A comparison of three indicators for identifying Mexican Americans in epidemiologic research. Methodological findings from the San Antonio Heart Study.
Because the issue of how to empirically identify Mexican Americans in health-related research is still unresolved, the authors compared the performance of three indicators for identifying Mexican Americans across five distinct population subgroups: men and women in two age strata, and residents in low, middle, and high socioeconomic neighborhoods. Individual surname had the lowest sensitivity, specificity, and predictive values in the pooled population sample and varied the most widely on these parameters across population subgroups. Parental surnames, which are available on vital statistics and could easily be added to other health records used in secondary analyses, offered a significant improvement over individual surname in classifying persons as Mexican American. The San Antonio Heart Study (SAHS) algorithm, a nine-item indicator which uses parental surnames, birthplace of both parents, self-declared ethnic identity, and ethnic background of grandparents, had the highest sensitivity, specificity, and predictive values and varied the least on these parameters across different sex, age, and socioeconomic status population subgroups. The performance of all indicators was lower at the higher socioeconomic status levels. The findings suggest that it may be useful to use parental surnames as an indicator for Mexican-American ethnicity in research involving vital statistics and to add parental surnames to other health records frequently used in secondary analyses. Since the SAHS algorithm can be adapted for use with non-Mexican origin Hispanic subgroups, it may be a useful indicator for Mexican-American (or other Hispanic) ethnicity in survey research.
Adult↗
Employment status and women's protection against coronary heart disease. Findings from the San Antonio Heart Study.
This study examined whether currently employed women are at increased risk of coronary heart disease relative to full-time homemakers. Subjects were 1,041 Mexican-American and non-Hispanic white women aged 25-64 years, residing in households randomly selected from three socioculturally distinct neighborhoods in San Antonio, Texas. No statistically significant differences between employed women and homemakers were found for obesity, total serum cholesterol, low density lipoprotein cholesterol, systolic and diastolic blood pressures, or cigarette smoking. Highly significant differences favoring employed women over homemakers were found for both Mexican Americans and non-Hispanic whites in high density lipoprotein (HDL) cholesterol, ratio of HDL cholesterol to total cholesterol, and triglycerides. These differences were not explained by obesity, exercise, cigarette smoking, alcohol consumption, use of exogenous estrogens, and use of oral contraceptives, or by the healthy worker effect, and were observed at all occupational levels. Employed women ate a less atherogenic diet than full-time homemakers, but it is not clear that this nutritional factor could explain the differences in HDL cholesterol and triglycerides found in this study. The magnitude of the employment status difference in HDL cholesterol for both ethnic groups was in a range (3-4 mg/100 ml) associated with protection against coronary heart disease.
Adult↗
The role of behavioral variables and fat patterning in explaining ethnic differences in serum lipids and lipoproteins.
Mexican Americans have been previously reported to have greater adiposity, higher triglyceride levels, and lower high density lipoprotein (HDL) cholesterol levels than Anglos. This study investigated the relationship between behavioral variables (caloric balance, cigarette and alcohol consumption, exercise, postmenopausal estrogen or oral contraceptive use) and fat patterning (central vs. peripheral distribution of adiposity) in the San Antonio Heart Study (1979-1982) (n = 2,102) to explain the ethnic difference in lipids and lipoproteins. Adjustment for caloric balance (as reflected by body mass index) narrowed the ethnic difference in triglyceride and HDL levels for both sexes, while adjustment for smoking widened the ethnic difference. For females, the ethnic difference was also decreased by adjustment for alcohol and estrogen use. However, adjustment for these behavioral variables did not completely eliminate the ethnic difference in lipids and lipoproteins in either sex. Increased central adiposity, more characteristic of Mexican Americans than Anglos, was positively associated with triglycerides and negatively associated with HDL levels, especially in females. Fat patterning made a more important contribution to the prediction of triglyceride and HDL levels than did the other behavioral variables (except for caloric balance) and, in general, eliminated ethnic differences in lipids and lipoproteins. Epidemiologists should consider the use of a centrality index to distinguish different types of adiposity since it is easy and inexpensive to measure.
Adipose Tissue↗