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Biomedical subjects

S M Haffner

Publications and source records attributed to S M Haffner.

At least 181 records · Page 10Linked to original sources
PubMed1994

Is there a sex difference in the association of plasma insulin level and insulin sensitivity with serum lipids and lipoproteins?

Previous studies on the relationship between the plasma insulin level, insulin sensitivity (SI), serum lipids, and lipoproteins have been performed predominantly in men. Therefore, we investigated whether there is a sex difference in the association of insulin level during an oral glucose tolerance test and SI with lipids and lipoproteins among normoglycemic men and women aged 53 to 61 years. SI was determined by the minimal model from the frequently sampled intravenous glucose tolerance test (IVGTT). There were no correlations between total cholesterol or low-density lipoprotein (LDL) cholesterol and insulin level or SI. High-density lipoprotein (HDL) cholesterol correlated inversely with fasting insulin (r = -.26, P < .05 in men; r = -.29, P < .01 in women) and 2-hour insulin (r = -.31, P < .01 in men; r = -.39, P < .001 in women) and positively with SI (r = .28, P = .05 in men; r = .43, P < .001 in women). Total and very-low-density lipoprotein (VLDL) triglycerides correlated positively with fasting insulin (r = .43, P < .001 in men; r = .42, P < .001 in women) and 2-hour insulin (r = .50, P < .001 in men; r = .31, P < .01 in women) and inversely with (r = -.49, P < .001 in men; r = -.40, P < .001 in women). In multiple regression analyses including age, body mass index (BMI), waist to hip ratio, 2-hour glucose, fasting or 2-hour insulin, and SI, only BMI was associated with HDL cholesterol level in men.(ABSTRACT TRUNCATED AT 250 WORDS)

Female↗
PubMed1994

Decreased testosterone and dehydroepiandrosterone sulfate concentrations are associated with increased insulin and glucose concentrations in nondiabetic men.

Although many studies indicate that increased androgenicity is associated with insulin resistance and hyperinsulinemia in both premenopausal and postmenopausal women, relatively few data are available on this relationship in men. We examined the association of sex hormone-binding globulin (SHBG), total and free testosterone, dehydroepiandrosterone sulfate (DHEA-SO4), and estradiol to glucose and insulin concentrations before and during an oral glucose tolerance test in 178 men from the San Antonio Heart Study, a population-based study of diabetes and cardiovascular disease. Total and free testosterone and DHEA-SO4 were significantly inversely associated with insulin concentrations. Free testosterone and DHEA-SO4 were also significantly inversely correlated with glucose concentrations. SHBG was weakly positively associated with glucose concentrations. Estradiol was not related to glucose or insulin concentrations. After adjustment for age, obesity, and body fat distribution, insulin concentrations remained significantly inversely correlated with free testosterone (r = -.23), total testosterone (r = -.21), and DHEA-SO4 (r = -.21; all P < .01). In conclusion, we observed that increased testosterone and DHEA-SO4 are associated with lower insulin concentrations in men. This is in striking contrast to women, where increased androgenicity is associated with insulin resistance and hyperinsulinemia.

Adult↗
PubMed1994

Lack of association between sex hormones and Lp(a) concentrations in American and Finnish men.

Sex hormones may play a role in the determination of cardiovascular disease. Recently lipoprotein(a) (Lp[a]) has been recognized as a risk factor for coronary heart disease. Estrogens and anabolic steroids have been reported to alter Lp(a) levels, yet no data are available on the association between in vivo concentrations of sex hormones and Lp(a) concentrations. We examined the possible associations of sex hormone-binding globulin, total and free testosterone, estradiol, and dehydroepiandrosterone sulfate to Lp(a) concentrations in men in two population-based studies (San Antonio Heart Study [n = 178] and a Finnish study on the association between insulin resistance and atherosclerosis [n = 87]). In neither study were sex hormones significantly related to Lp(a) concentrations. In addition, Lp(a) was significantly related to apolipoprotein(a) molecular weight (which was measured in the Finnish study only). These results were unchanged when Lp(a) concentrations were adjusted for apolipoprotein(a) molecular weight (a strong correlate of Lp[a] concentrations). We conclude that in vivo concentrations of sex hormones are unlikely to be associated with Lp(a) concentrations in men.

Adult↗
PubMed1994

Hyperinsulinemia predicts multiple atherogenic changes in lipoproteins in elderly subjects.

Several studies have shown that hyperinsulinemia and insulin resistance are associated with high triglyceride and low high-density lipoprotein (HDL) cholesterol levels. However, previous studies have been cross-sectional, and thus the presence of hyperinsulinemia or insulin resistance could be a consequence of the underlying lipid disorder instead of its cause. Therefore, we examined the relation of fasting insulin level measured in a cross-sectional study in nondiabetic subjects 65 to 74 years old (n = 881) to the risk of developing lipid disorders 3.5 years later. The incidence of the following lipid abnormalities was calculated: hypertriglyceridemia (n = 49/732, incident cases/subjects free of the particular disorder at baseline), high low-density lipoprotein (LDL) cholesterol level (n = 43/696), low HDL cholesterol level (n = 33/708), high apolipoprotein (apo) B level (n = 72/699), low apoAI level (n = 47/711), low serum LDL cholesterol/serum apoB ratio (n = 55/685), and low serum HDL cholesterol/serum apoAI ratio (n = 48/707). Baseline insulin level was not significantly associated with the development of high LDL cholesterol or low HDL cholesterol levels. Baseline insulin was associated with the development of hypertriglyceridemia (odds ratio [OR], 1.64; 95% confidence interval [CI], 1.12 to 2.40; P = .011), high apoB (OR, 1.54; 95% CI, 1.13 to 2.10; P = .006), low apoAI (OR, 1.72; 95% CI, 1.22 to 2.42; P = .002), low LDL cholesterol/apoB ratio (OR, 1.99; 95% CI, 1.36 to 2.90; P < .001), and low HDL cholesterol/apoAI ratio (OR, 1.93; 95% CI, 1.34 to 2.79; P < .001).(ABSTRACT TRUNCATED AT 250 WORDS)

Aged↗
PubMed1994

Insulin sensitivity is not an independent determinant of plasma plasminogen activator inhibitor-1 activity.

It recently has been hypothesized that increased plasma plasminogen activator inhibitor-1 (PAI-1) activity could be a possible link between insulin resistance and coronary heart disease. However, it is not known whether insulin sensitivity per se is a determinant of plasma PAI-1 activity or whether other intermediates could explain this association. We investigated the relationship between plasma PAI-1 activity and insulin sensitivity, obesity, distribution of body fat, blood pressure, plasma insulin concentration, and serum lipid levels in normoglycemic men (n = 61) and women (n = 77) 53 to 61 years old who participated in a previous population-based study. Insulin sensitivity was estimated by the minimal model from a frequently sampled intravenous glucose tolerance test. In univariate analyses, PAI-1 correlated positively with body mass index, waist-to-hip ratio (WHR), fasting and 2-hour insulin levels, and triglyceride level in both men and women. Furthermore, in women PAI-1 correlated inversely with high-density lipoprotein (HDL) cholesterol level. There was an inverse relationship between PAI-1 and insulin sensitivity (r = -.39, P < .01 in men; r = -.38, P < .001 in women). In multivariate analyses in men, insulin sensitivity failed to show any significant association with PAI-1. In contrast, triglyceride level and body mass index were independently associated with PAI-1. Also in women, insulin sensitivity was not independently associated with PAI-1. In women, WHR and HDL cholesterol concentration or WHR and 2-hour insulin concentration were independently related to PAI-1.(ABSTRACT TRUNCATED AT 250 WORDS)

Blood Glucose↗
PubMed1994

Evaluation of two insulin assays in insulin resistance syndrome (syndrome X).

Recent data suggest that proinsulin is associated with cardiovascular risk factors in nondiabetic and diabetic subjects. Since most conventional insulin assays cross-react with proinsulin, it has been suggested that the associations of insulin concentrations with dyslipidemia and hypertension could actually reflect associations with proinsulin. We examined these associations by using both a conventional immunoreactive insulin assay and a specific Linco insulin assay that does not cross-react with proinsulin in 623 nondiabetic and in 180 non-insulin-dependent diabetic subjects who participated in the San Antonio Heart Study, a population-based study of diabetes and cardiovascular disease. Both the immunoreactive insulin assay and the specific Linco insulin assay were equally correlated with cardiovascular risk factors in nondiabetic subjects. Insulin concentrations were moderately correlated with high triglyceride and low high-density lipoprotein cholesterol levels and were weakly correlated with increased blood pressure. In diabetic subjects there were only weak associations between insulin and cardiovascular risk factors using either assay. We conclude that the association of insulin concentrations with cardiovascular risk factors is not a function of using insulin assays that cross-react with proinsulin and that for epidemiological studies of cardiovascular risk factors, conventional immunoreactive insulin assays are as good as the newer specific insulin assays.

Adult↗
PubMed1994

Disproportionately increased proinsulin levels are associated with the insulin resistance syndrome.

Recent data suggest that proinsulin may be associated with increased cardiovascular risk factors in both diabetic and nondiabetic subjects. We examined the relation of insulin, proinsulin, and the fasting proinsulin/insulin ratio to a number of metabolic disorders believed to be related to the insulin resistance syndrome (low high density lipoprotein cholesterol and high triglyceride levels, hypertension, and impaired glucose tolerance). Proinsulin was measured by a RIA, and insulin was measured by a Linco RIA that does not cross-react with proinsulin. The increased fasting proinsulin/insulin ratio was significantly associated with hypertension, low high density lipoprotein cholesterol and high triglyceride levels, and impaired glucose tolerance in 423 nondiabetic subjects. The fasting proinsulin/insulin ratio increased significantly with the number of metabolic disorders (zero, 0.060; one, 0.086; two, 0.098; three, 0.177; four, 0.182; P < 0.001). The increased proinsulin/insulin ratio was also associated with a greater number of metabolic disorders in diabetic subjects. Our results show that particularly nondiabetic individuals with the insulin resistance syndrome not only have hyperinsulinemia as a marker of insulin resistance, but also show an increase in proinsulin relative to insulin, which may reflect relative beta-cell failure or malfunction.

Anthropometry↗
PubMed1994

Proinsulin and specific insulin concentration in high- and low-risk populations for NIDDM.

Hyperinsulinemia and insulin resistance have been implicated as risk factors for the development of non-insulin-dependent diabetes mellitus (NIDDM). Recent data suggest that proinsulin may comprise a large proportion of immunoreactive insulin in subjects with NIDDM and possibly in those with impaired glucose tolerance (IGT) as well. Increased proinsulin concentrations are thought to be an early indicator of a failing pancreas. We examined proinsulin, insulin (using an assay that does not display appreciable cross-reactivity with proinsulin), and the fasting proinsulin:insulin ratio in 206 nondiabetic Mexican-American (a high-risk population for NIDDM) and 123 nondiabetic non-Hispanic white (a low-risk population for NIDDM) participants in the San Antonio Heart Study, a population-based study of diabetes and cardiovascular disease. Mexican-Americans had significantly higher fasting and 2-h proinsulin and insulin levels but similar fasting proinsulin:insulin ratios compared with non-Hispanic whites. After statistical adjustment for age, body mass index, waist-to-hip ratio, and glucose tolerance status, Mexican-Americans continued to have higher fasting and 2-h insulin and fasting and 2-h proinsulin concentrations but similar proinsulin:insulin ratios compared with non-Hispanic whites. The fasting proinsulin:insulin ratio was higher in 85 subjects with NIDDM compared with subjects with IGT or normal glucose tolerance (0.31, 0.09, and 0.07, respectively). Thus, nondiabetic subjects from a high-risk population for NIDDM are hyperinsulinemic (using an assay that does not cross-react with proinsulin) and, further, do not secrete more proinsulin relative to insulin itself than do nondiabetic subjects from a low-risk population.

Diabetes Mellitus, Type 2↗
PubMed1994

Insulin resistance, body fat distribution, and sex hormones in men.

Although many studies have suggested that increased androgenicity is associated with insulin resistance and hyperinsulinemia in both pre- and postmenopausal women, relatively few data are available on this relationship in men. We examined the association of body mass index (BMI), waist-to-hip ratio (WHR), sex hormone-binding globulin (SHBG), total and free testosterone, dehydroepiandrosterone sulfate (DHEA-SO4), and estradiol with insulin concentrations and whole-body glucose disposal in 87 men from a population-based study in Kuopio, Finland. BMI was significantly correlated with fasting insulin (r = 0.46), total whole-body glucose disposal (r = -0.30), glucose oxidation (r = -0.21), and nonoxidative glucose disposal (r = -0.25). WHR also was significantly associated with fasting insulin (r = 0.61), total whole-body glucose disposal (r = -0.54), glucose oxidation (r = -0.23), and nonoxidative whole-body glucose disposal (r = -0.50). SHBG and total and free testosterone were significantly associated with insulin concentrations and total and nonoxidative glucose disposal but not with glucose oxidation. DHEA-SO4 and estradiol were not associated with insulin, glucose concentrations, or whole-body glucose disposal in univariate analysis. In multivariate analysis, total whole-body glucose disposal was associated negatively with WHR and positively associated with total testosterone and SHBG; nonoxidative whole-body glucose disposal was associated negatively with WHR and positively associated with total and free testosterone. Glucose oxidation was significantly associated only with WHR. In conclusion, higher WHR and lower testosterone were strongly associated with a decrease in total and nonoxidative whole-body glucose disposal in men.

Adipose Tissue↗
PubMed1994

Microalbuminuria precedes the development of NIDDM.

Several studies have indicated that insulin resistance, elevated blood pressure (BP), and dyslipidemia precede the onset of non-insulin-dependent diabetes mellitus (NIDDM). Little data, however, exist on the presence of renal disease in prediabetic subjects. We measured albumin excretion in a cross-sectional population study in subjects 65-74 years of age living in eastern Finland in relation to the risk of developing diabetes 3.5 years later. The prevalence of microalbuminuria (urinary albumin-to-urinary creatinine ratio > or = 2 mg/mmol) was 1.3-, 1.8-, and 2.0-fold higher among subjects with impaired glucose tolerance (n = 242), newly diagnosed NIDDM subjects (n = 92), and previously diagnosed NIDDM subjects (n = 136), respectively, compared with subjects with normal glucose tolerance (n = 826). Nondiabetic subjects with microalbuminuria had multiple abnormalities in cardiovascular risk factors including elevated BP, high triglyceride concentration, high insulin concentration, and a low high-density lipoprotein cholesterol concentration, a cluster of risk factors typical for prediabetic individuals. The relationship between microalbuminuria and the incidence of NIDDM over the 3.5-year follow-up was studied in 891 subjects who were free of diabetes at baseline. Converters to diabetes (n = 69) had a higher prevalence of hypertension (68.1 vs. 54.4%, P < 0.05) and a higher prevalence of microalbuminuria (43.5 vs. 30.4%, P < 0.05) than nonconverters (n = 822). In logistic regression analysis, microalbuminuria predicted the development of NIDDM independently of BP level.(ABSTRACT TRUNCATED AT 250 WORDS)

Age Factors↗
PubMed1994

Effects of NIDDM on lipoprotein(a) concentration and apolipoprotein(a) size.

We investigated the effects of non-insulin-dependent diabetes mellitus (NIDDM) on lipoprotein(a) (Lp[a]) and apolipoprotein(a) (apo[a]) in a population of Mexican-Americans. In plasma samples from 536 subjects, we measured Lp(a) concentrations, and we estimated apo(a) isoform sizes following immunostaining of plasma proteins resolved using sodium dodecyl sulfate electrophoresis. We identified 81 diabetic subjects who had 108 distinct apo(a) isoform bands. We then identified 81 nondiabetic subjects from the remainder who were closely matched for apo(a) phenotype (i.e., number and size of apo(a) isoform bands). As expected, the diabetic group had higher levels of glucose and insulin (both fasted and 2 h after glucose challenge) and triglycerides, and lower levels of high-density lipoprotein (HDL) cholesterol when compared with the matching nondiabetic group. Moreover, the diabetic group also had significantly lower Lp(a) concentrations than the nondiabetic subjects (10.6 vs. 13.6 mg/dl, P = 0.045) using a paired Student's t test. To detect the effects of diabetes on apo(a) size, we identified by pedigree analysis the nondiabetic family members who possessed alleles identical to those in the diabetic group. When we compared the average sizes for each allele, we found that apo(a) isoforms averaged 4.1 kDa larger in diabetic subjects than the genetically identical apo(a) measured in nondiabetic subjects (P = 0.044, n = 36 alleles). In summary, we have detected significant effects of NIDDM both on Lp(a) concentrations and on apo(a) size.

Apolipoproteins↗
PubMed1994

Greater effect of diabetes on LDL size in women than in men.

OBJECTIVE: Coronary heart disease (CHD) is increased two- to fourfold in subjects with NIDDM compared with normoglycemic subjects. This excess risk is only partially explained by conventional risk factors. We studied the effect of non-insulin-dependent diabetes mellitus (NIDDM) on the size of low-density lipoproteins (LDL). RESEARCH DESIGN AND METHODS: We examined the effect of NIDDM on LDL size and subclass pattern B (LDL size < 253.5 A) in 95 diabetic subjects and 371 nondiabetic subjects from the San Antonio Heart Study, a population-based study of diabetes and cardiovascular disease. RESULTS: LDL size (A) was significantly lower in diabetic subjects (men: 252.2 +/- 1.8; women: 254.7 +/- 1.3) than in nondiabetic subjects (men: 256.1 +/- 0.8; women: 259.7 +/- 0.7) (P = 0.007). After the use of analysis of covariance to adjust for triglyceride and high-density lipoprotein cholesterol, LDL size was still significantly lower in diabetic women than in nondiabetic women. In men, however, diabetes was no longer significantly associated with LDL size after similar adjustments. Fasting glucose was more strongly correlated with LDL size in women (r = -0.30) than in men (r = -0.18). CONCLUSIONS: We conclude that LDL size is significantly lower in diabetic subjects of both sexes than in nondiabetic subjects, but that diabetic dyslipidemia accounts for the association in diabetic men. The stronger association between LDL size and diabetes in women than in men may partially explain the greater relative risk of CHD observed in women with NIDDM in some studies.

Adult↗
PubMed1994

Clinical characteristics of type II diabetic subjects consuming high versus low carbohydrate diets in Mexico City and San Antonio, Texas.

OBJECTIVE: To compare the clinical status of type II diabetic subjects identified in two population-based surveys, one performed in Mexico City, Mexico and the other in San Antonio, Texas. RESEARCH DESIGN AND METHODS: In a low income area of Mexico City, 3,517 age-eligible (35-64 years of age) individuals were randomly selected of whom 3,319 were interviewed at home and 2,198 were examined in a clinic (response rates 62.5%). In San Antonio, 2,357 similarly aged low-income Mexican Americans were randomly selected of whom 2,076 were interviewed at home and 1,511 were examined (response rate 64.1%). Oral glucose tolerance tests were performed at both sites and diabetes was diagnosed according to the World Health Organization (WHO) criteria. In Mexico City, 288 type II diabetic individuals were identified, and 255 were identified in San Antonio. The following variables were measured: height, weight, subscapular and triceps skinfolds, waist-to-hip circumference ratios (WHR), systolic and diastolic blood pressure (random 0 sphygmomanometer), fasting and 2-h postglucose load glucose and insulin concentrations, and fasting total-cholesterol, HDL-cholesterol, and triglyceride (TG) levels. A food frequency questionnaire was used to estimate total calories and the percentage of calories derived from protein, fat, and carbohydrate. Only type II diabetic patients were included in the analyses. Age-adjustment was performed by analysis of covariance for continuous variables and by the Mantel-Haenszel procedure for discrete variables. RESULTS: The mean age, the percentage newly diagnosed cases, and the percentage of males were similar in both sites. The percentage of diabetic patients treated with oral agents was significantly higher in Mexico City (56.9 vs. 72.7% in San Antonio and Mexico City, respectively, P < 0.001), whereas the percentage treated with insulin was significantly higher in San Antonio (18.8 vs. 2.1% for San Antonio and Mexico City, respectively, P < 0.001). A significant difference was observed in the percentage of calories derived from carbohydrate (61.7-63.2 vs. 47.1-47.5% for Mexico City and San Antonio, respectively, P < 0.001) and fat (18.4-20.0 and 30.1-33.0% for Mexico City and San Antonio, respectively, P < 0.001). Body mass index (BMI) was higher in San Antonio (27.6-30.4 vs. 30.2-32.9% for Mexico City and San Antonio, respectively, P < 0.05). Total serum cholesterol was similar at both sites. HDL cholesterol, however, was lower in Mexico City, both in newly and in previously diagnosed patients (30.5-35.8 vs. 39.6-43.3 mg/dl in Mexico City and San Antonio, respectively, P < 0.001). TG levels were higher in Mexico City patients (187-249 vs. 167-179 mg/dl in Mexico City and San Antonio, respectively, P < 0.001). The association between diabetes and the anthropometric and metabolic variables was similar in Mexico City and San Antonio with the following exceptions: Diabetes in Mexico City was associated with less of an elevation in BMI, WHR, and fasting insulin concentration and less of a reduction in the 2-h postoral glucose load insulin concentration compared with diabetes in San Antonio. In addition, although diabetes was associated with a lower HDL in San Antonio subjects, no association appeared between diabetes and HDL in Mexico City subjects. CONCLUSIONS: Diabetic subjects in Mexico City were more likely to be treated with oral agents and less likely to be treated with insulin compared with San Antonio patients. Previously diagnosed diabetic subjects in San Antonio had higher BMIs than diabetic subjects in Mexico City. Diabetic subjects in Mexico City ate less fat but more carbohydrate than those in San Antonio. TG levels were higher and HDL-cholesterol levels were lower in Mexico City diabetic subjects compared with those in San Antonio. San Antonio diabetic subjects had lower HDL levels than nondiabetic subjects but, in Mexico City, HDL levels were similar in diabetic subjects and nondiabetic subjects...

Adult↗
PubMed1994

Increased risk of non-insulin-dependent diabetes mellitus in elderly hypertensive subjects.

BACKGROUND: In several studies hypertension has been shown to be associated with an increased incidence of non-insulin-dependent diabetes mellitus (NIDDM). This may be due to hypertension itself or to the deleterious effects of some antihypertensive agents on glucose tolerance and insulin sensitivity. METHODS: We examined the 3.5-year incidence of diabetes mellitus in relation to hypertension and antihypertensive medication in a population-based study of elderly subjects (n = 805) aged 65-74 years in Kuopio, Finland. RESULTS: Of the subjects studied, 60% had hypertension at baseline and 50% of the hypertensive subjects were on drug therapy at baseline. Hypertensive subjects had a significantly higher incidence of NIDDM than non-hypertensive subjects. However, after adjustment for age, body mass index, waist: hip ratio, sex, and fasting glucose and insulin levels, the increased risk of NIDDM in hypertensive subjects was no longer statistically significant. Subjects with high blood pressure (> or = 160/95 mmHg) at the baseline examination who were not taking beta-blockers or diuretic medication had a 1.56-fold increased risk of developing NIDDM, whereas subjects with hypertension who were taking those agents had a 1.88-fold risk of developing NIDDM compared with subjects with normal blood pressure. The risk of developing NIDDM was accompanied by elevated fasting insulin levels. After adjustment for age, sex, body mass index, waist:hip ratio, and fasting glucose and insulin levels, hypertensive subjects taking diuretics or beta-blockers, or both, still had a 1.56-fold increased risk of developing NIDDM relative to normotensive subjects. Hypertensive subjects taking diuretics or beta-blockers, or both, had a significantly higher incidence of NIDDM than hypertensive subjects not on pharmacological therapy. However, after adjustment for 2-h glucose and insulin concentrations, the incidence of NIDDM did not differ between the hypertensive subjects. CONCLUSION: The data presented suggest that the increased risk of NIDDM in hypertensive subjects taking beta-blockers or diuretics, or both, is explained at least partly by metabolic disturbances related to drug therapy.

Adrenergic beta-Antagonists↗
PubMed1994

Predictors of weight change in a bi-ethnic population. The San Antonio Heart Study.

To study demographic, anthropometric and metabolic determinants of weight change, we divided a random sample of 1493 Mexican Americans and non-Hispanic whites into two groups: weight gainers and weight losers. This classification was based on the weight change during the eight-year follow-up of participants of the San Antonio Heart Study, a population-based longitudinal study of diabetes and cardiovascular disease. Men gained significantly less weight and lost more weight than women. The average gains for weight gainers were 6.1 kg and 6.8 kg for men and women respectively; and the average losses for weight losers were 4.4 and 3.4 kg for men and women respectively. There was no ethnic difference in either category of weight change. Weight gainers were significantly younger and leaner than weight losers. Fasting insulin was the only independent metabolic predictor of weight change and only among the most obese tertile of the population: the higher the baseline levels of fasting insulin, the less the likelihood of gaining and the greater the likelihood of losing weight. Our results support the hypothesis that insulin resistance is part of a negative feedback mechanism that attenuates further weight gain among the obese.

Adult↗
PubMed1993

Is microalbuminuria part of the prediabetic state? The Mexico City Diabetes Study.

Microalbuminuria is associated with increased cardiovascular mortality in both diabetic and non-diabetic subjects. A number of studies have indicated that insulin resistance, increased blood pressure and dyslipidaemia precede the onset of clinical diabetes. We examined various correlates of microalbuminuria in 1,298 non-diabetic subjects who participated in the Mexico City Diabetes Study, a population-based study of diabetes and cardiovascular risk factors. Both parental history of diabetes and impaired glucose tolerance were significantly associated with microalbuminuria. These results were not explained by differences in age or blood pressure between subjects with or without a parental history of diabetes or impaired glucose tolerance. In addition, subjects with microalbuminuria had increased 2-h insulin and triglyceride concentrations, a higher prevalence of hypertension, and decreased high density lipoprotein cholesterol concentrations relative to subjects without microalbuminuria. These results that microalbuminuria may be a feature of the prediabetic state.

Albuminuria↗
PubMed1993

The association of obesity and glucose and insulin concentrations with bone density in premenopausal and postmenopausal women.

Obese subjects have increased bone density relative to non-obese subjects, yet this relationship is not fully understood. We examined whether alterations in glucose or insulin concentrations might explain the effect of obesity on bone density in 317 women from the San Antonio Heart Study, a population-based study of diabetes. We measured fasting and 2-hour plasma glucose and fasting and 2-hour serum insulin levels. Bone density was assessed by a Hologic dual-photon absorptiometer. Lumbar spine and femoral neck density were positively correlated with body mass index (BMI). Femoral neck density also was positively correlated with fasting insulin level in younger women after adjustment for age (r = .214, P < .01). After further adjustment for BMI, femoral neck density was not significantly correlated with fasting insulin level (P = .08). The magnitude of the estimated femoral neck density difference for a 32.2-microU/mL decrease in fasting insulin level (the difference in insulin concentrations between nondiabetics and diabetics) was 0.13 g/cm2. Adjustment for glucose and insulin concentrations does not explain the association between bone density and obesity.

Adult↗