Comparing coronary artery cross-sectional area among asymptomatic South Asian, White, and Black participants: the MASALA and CARDIA studies

BACKGROUND

South Asian individuals have high risk of atherosclerotic cardiovascular disease (ASCVD). Some investigators suggest smaller coronary artery size may be partially responsible.

METHODS

We compared the left anterior descending (LAD) artery cross-sectional area (CSA) (lumen and arterial wall) among South Asians in the Mediators of Atherosclerosis in South Asians Living in America (MASALA) study with White and Black participants in the Coronary Artery Risk Development in Young Adults (CARDIA) study, adjusting for BMI, height, and other ASCVD risk factors. We used thin-slice non-contrast cardiac computed tomography to measure LAD CSA. We used linear regression models to determine whether race/ethnicity was associated with LAD CSA after adjusting for demographic factors, BMI, height, coronary artery calcium (CAC), and traditional cardiovascular risk factors.

RESULTS

Our sample included 3,353 participants: 513 self-identified as South Asian (44.4% women), 1286 as Black (59.6% women), and 1554 as White (53.5% women). After adjusting for age, BMI, height, there was no difference in LAD CSA between South Asian men and women compared to White men and women, respectively. After full adjustment for CVD risk factors, LAD CSA values were: South Asian women (19.9 mm2, 95% CI [18.8 - 20.9]) and men (22.3 mm2, 95% CI [21.4 - 23.2]; White women (20.0 mm2, 95% CI [19.4-20.5]) and men (23.6 mm2, 95% CI [23.0-24.2]); and Black women (21.6 mm2, 95% CI [21.0 - 22.2]) and men (26.0 mm2, 95% CI [25.3 - 26.7]). Height, BMI, hypertension, CAC, and age were positively associated with LAD CSA; current and former cigarette use were inversely associated.

CONCLUSIONS

South Asian men and women have similar LAD CSA to White men and women, and smaller LAD CSA compared to Black men and women, respectively, after accounting for differences in body size. Future studies should determine whether LAD CSA is associated with future ASCVD events.

Examining if the relationship between BMI and incident type 2 diabetes among middle-older aged adults varies by race/ethnicity: evidence from the Multi-Ethnic Study of Atherosclerosis (MESA)

AIMS

Disparities persist on the prevalence of undiagnosed type 2 diabetes in racial/ethnic minorities in the USA. This study evaluated the association between BMI and incident type 2 diabetes risk by racial/ethnic group, to determine whether BMI and presence of type 2 diabetes risk factors may help clinicians better target type 2 diabetes screening.

METHODS

This prospective cohort analysis included 5659 adults free of type 2 diabetes at baseline from the Multi-Ethnic Study of Atherosclerosis (MESA), a population-based cohort (2000-2011). BMI was measured at baseline and time-updated at subsequent visits. Incident type 2 diabetes was defined as fasting glucose ≥ 7.0 mmol/l, or use of any diabetes medications.

RESULTS

The mean (sd) age was 62 (10) years and 42% of participants were white, 26% African American, 20% Hispanic and 12% Chinese American. During follow-up, 696 (12%) new type 2 diabetes cases were observed. In age- and sex-adjusted models, in the presence of one or more type 2 diabetes risk factors (the most common scenario), a 10% risk of incident type 2 diabetes was observed at a BMI of 21.7 kg/m² [95% confidence interval (CI) 20.1 to 22.8] in Chinese Americans, 23.8 kg/m² (22.7 to 24.9) in Hispanics, 24.7 kg/m² (23.7 to 25.6) in African Americans and 26.2 kg/m² (25.1 to 26.9) in white participants.

CONCLUSIONS

This study supports including BMI and presence of type 2 diabetes risk factors as action points for clinicians to prioritize which adults aged ≥ 45 years should be screened. The application of race/ethnicity-specific BMI thresholds may reduce the disparity of undiagnosed type 2 diabetes observed in minority groups.

Isolated HbA1c identifies a different subgroup of individuals with type 2 diabetes compared to fasting or post-challenge glucose in Asian Indians: The CARRS and MASALA studies

AIMS

Guidelines recommend hemoglobin A1c (HbA1c) as a diagnostic test for type 2 diabetes, but its accuracy may differ in certain ethnic groups.

METHODS

The prevalence of type 2 diabetes by HbA1c, fasting glucose, and 2 h glucose was compared in 3016 participants from Chennai and Delhi, India from the CARRS-2 Study to 757 Indians in the U.S. from the MASALA Study. Type 2 diabetes was defined as fasting glucose ≥ 7.0 mmol/L, 2-h glucose ≥ 11.1 mmol/L, or HbA1c ≥ 6.5%. Isolated HbA1c diabetes was defined as HbA1c ≥ 6.5% with fasting glucose < 7.0 mmol/L and 2 h glucose < 11.1 mmol/L.

RESULTS

The age, sex, and BMI adjusted prevalence of diabetes by isolated HbA1c was 2.9% (95% CI: 2.2-4.0), 3.1% (95% CI: 2.3-4.1), and 0.8% (95% CI: 0.4-1.8) in CARRS-Chennai, CARRS-Delhi, and MASALA, respectively. The proportion of diabetes diagnosed by isolated HbA1c was 19.4%, 26.8%, and 10.8% in CARRS-Chennai, CARRS-Delhi, and MASALA respectively. In CARRS-2, individuals with type 2 diabetes by isolated HbA1c milder cardio-metabolic risk than those diagnosed by fasting or 2-h measures.

CONCLUSIONS

In Asian Indians, the use of HbA1c for type 2 diabetes diagnosis could result in a higher prevalence. HbA1c may identify a subset of individuals with milder glucose intolerance.

Preliminary evidence supports circulating microRNAs as prognostic biomarkers for type 2 diabetes

Background

Circulating microRNAs are emerging as potential prognostic biomarkers for the development of type 2 diabetes. However, microRNAs are also associated with complications from impaired glucose metabolism (e.g. endothelial cell function). Prior studies have not evaluated for associations between trajectories of circulating microRNAs with trajectories of fasting blood glucose over time and the responses to behavioral interventions to reduce risk. This study performed longitudinal assessment of microRNAs and fasting blood glucose and identified relationships between microRNAs and behavioral risk reduction interventions.

Methods

MicroRNAs (n = 353) were measured in subsets (n = 10, n = 8) of participants from previously completed clinical trials that studied behavioral risk reduction interventions. Fasting blood glucose trajectories were associated with changes in 45 microRNAs over 12 months.

Results

Following a 3‐month physical activity and dietary intervention compared with baseline, 13 microRNAs were differentially expressed. Seven microRNAs (i.e. miR‐106b, miR‐20b, miR‐363, miR‐486, miR‐532, miR‐92a and miR‐93) were commonly identified between the two analyses.

Conclusions

Further studies are needed to determine which microRNAs are prognostic biomarkers of risk for type 2 diabetes versus consequences of impaired glucose metabolism. Additional future directions of this research are to differentiate whether microRNAs are prognostic and/or diagnostic biomarkers for risk for type 2 diabetes and predictive biomarkers of responses to risk reduction interventions.

Circulating cellular adhesion molecules and risk of diabetes: the Multi-Ethnic Study of Atherosclerosis (MESA)

AIMS

To test the hypothesis that soluble cellular adhesion molecules would be positively and independently associated with risk of diabetes.

METHODS

Soluble levels of six cellular adhesion molecules (ICAM-1, E-selectin, VCAM-1, E-cadherin, L-selectin and P-selectin) were measured in participants in the Multi-Ethnic Study of Atherosclerosis, a prospective cohort study. Participants were then followed for up to 10 years to ascertain incident diabetes.

RESULTS

Sample sizes ranged from 826 to 2185. After adjusting for age, sex, race/ethnicity, BMI and fasting glucose or HbA1c , four cellular adhesion molecules (ICAM-1, E-selectin, VCAM-1 and E-cadherin) were positively associated with incident diabetes and there was a statistically significant trend across quartiles. Comparing the incidence of diabetes in the highest and lowest quartiles of each cellular adhesion molecule, the magnitude of association was largest for E-selectin (hazard ratio 2.49; 95% CI 1.26-4.93) and ICAM-1 (hazard ratio 1.76; 95% CI 1.22-2.55) in fully adjusted models. Tests of effect modification by racial/ethnic group and sex were not statistically significant for any of the cellular adhesion molecules (P > 0.05).

CONCLUSIONS

The finding of significant associations between multiple cellular adhesion molecules and incident diabetes may lend further support to the hypothesis that microvascular endothelial dysfunction contributes to risk of diabetes.

Endogenous sex steroid hormones and glucose in a South-Asian population without diabetes: the Metabolic Syndrome and Atherosclerosis in South-Asians Living in America pilot study

AIMS

To examine the associations between endogenous sex steroid hormones (oestradiol, testosterone and sex hormone-binding globulin) with diabetes risk in a South-Asian population living in the USA.

METHODS

We used data from the Metabolic Syndrome and Atherosclerosis in South-Asians Living in America pilot study. The analytical sample included 60 women and 45 men of Asian Indian origin living in the San Francisco Bay Area, who were free from diabetes and cardiovascular disease and did not use exogenous sex steroids. Sex steroid hormone levels were assessed by validated conventional radioimmunoassays, and visceral and hepatic adiposity were assessed by computed tomography. We used multivariable regression to examine the association between endogenous sex steroid hormone levels (log-transformed) and fasting glucose and 2-h glucose levels in a series of sex-stratified models adjusted for age, waist circumference, visceral and hepatic adiposity, and insulin resistance.

RESULTS

In age-adjusted models, lower levels of sex hormone-binding globulin (β = -0.18, 95% CI -0.30, -0.06) and higher levels of free testosterone (β = 0.14, 95% CI 0.02, 0.26) were associated with elevated fasting glucose levels in South-Asian women, whereas lower levels of sex hormone-binding globulin (β = -0.14, 95% CI -0.26, -0.02) and lower levels of total testosterone (β = -0.12, 95% CI -0.24, 0.00) were associated with elevated fasting glucose levels in South-Asian men. Adjustment for waist circumference, visceral adiposity and insulin resistance attenuated most of these associations, while adjustment for hepatic adiposity strengthened some of the observed associations. Similar results were found for 2-h glucose levels.

CONCLUSIONS

Results were consistent with previous research, which suggests that endogenous sex steroid hormones are a risk factor for diabetes across multiple race/ethnic groups. Additional studies are needed to determine whether visceral fat is a mediator or confounder of associations between sex steroid hormone and glucose levels.

Acculturation and Subclinical Atherosclerosis among U.S. South Asians: Findings from the MASALA study

OBJECTIVE

Longer duration of residence among immigrants to the United States, a proxy measure of acculturation, has been associated with higher subclinical atherosclerosis. South Asian immigrants are the second fastest growing immigrant group in the U.S. but little is known about the effects of acculturation with atherosclerosis in this high cardiovascular risk population.

METHODS

We conducted a cross-sectional analysis using data from a community-based cohort called the Mediators of Atherosclerosis in South Asians Living in America (MASALA) study. Participants (n=900) were between ages of 40-84 years and had no existing cardiovascular disease. We developed a multi-dimensional measure of acculturation in South Asians, called traditional cultural beliefs, and measured other proxy measures of acculturation to determine whether they were associated with higher levels of subclinical atherosclerosis after controlling for socioeconomic, behavior/lifestyle, and cardiovascular risk factors.

RESULTS

Mean duration of residence in the U.S. was 27±11 years and tertiles of strength of traditional cultural beliefs were examined. Longer duration of U.S. residence was associated with higher levels of coronary artery calcium even after adjustment for covariates and lifestyle mediators. The novel measure of strength of traditional cultural beliefs was associated with lower common carotid intima media thickness among those with moderate traditional beliefs only.

CONCLUSIONS

These findings support the need for better conceptualization and measurement of how migration influences cultural beliefs and practices, and their subsequent influence on health behaviors and cardiovascular disease risk.

Changes in procoagulants track longitudinally with insulin resistance: findings from the coronary artery risk development in young adults (CARDIA) study

AIMS

To examine the association between changes in procoagulants (fibrinogen factors VII and VIII and von Willebrand factor) and the risk of insulin resistance.

METHODS

Using data from the Coronary Artery Risk Development in Young Adults study, we followed 2398 black and white adults without diabetes, aged 25-37 years at year 7, to year 20. Levels of fibrinogen factors VII and VIII and von Willebrand factor were divided in tertiles (low/middle/high) at years 7 and 20 and four groups reflecting changes were defined: 'low' (low at years 7 and 20), 'stable' (low/middle at years 7 and 20, but not both low at years 7 and 20), 'high' (high at year 7 and low/middle at year 20; or low/middle at year 7 and high at year 20) and 'highest' (high at years 7 and 20). Linear regression models were used to evaluate 13-year changes (year 20-year 7) in fibrinogen level and factors VII, VIII and von Willebrand change groups in relation to insulin resistance measures.

RESULTS

Homeostasis model assessment of insulin resistance (year 20) and changes in log homeostasis model assessment of insulin resistance (year 20-year 7) were significantly associated with the 13-year increase in fibrinogen (P < 0.001). Compared with participants in the low group, those in the high group had significantly higher levels of homeostasis model assessment of insulin resistance (year 20) and changes in homeostasis model assessment of insulin resistance (year 20-year 7) for fibrinogen factor VII and von Willebrand factor (P < 0.017). No significant associations were observed between fibrinogen VIII and insulin resistance measures.

CONCLUSIONS

An increase in fibrinogen level and persistently high levels of factor VII and von Willebrand factor are significantly associated with increased risk of insulin resistance. These findings provide new insight into the mechanisms to explain the heightened risk for thrombosis in adults with insulin resistance/diabetes.

Dietary patterns, insulin sensitivity and inflammation in older adults

Background/Objectives

Several studies have linked dietary patterns to insulin sensitivity and systemic inflammation, which affect risk of multiple chronic diseases. The purpose of this study was to investigate the dietary patterns of a cohort of older adults, and examine relationships of dietary patterns with markers of insulin sensitivity and systemic inflammation.

Subjects/Methods

The Health, Aging and Body Composition (Health ABC) Study is a prospective cohort study of 3075 older adults. In Health ABC, multiple indicators of glucose metabolism and systemic inflammation were assessed. Food intake was estimated with a modified Block food frequency questionnaire (FFQ). In this study, dietary patterns of 1751 participants with complete data were derived by cluster analysis.

Results

Six clusters were identified, including a ‘Healthy foods’ cluster, characterized by higher intake of lowfat dairy products, fruit, whole grains, poultry, fish and vegetables. In the main analysis, the ‘Healthy foods’ cluster had significantly lower fasting insulin and HOMA-IR than the ‘Breakfast cereal’ and ‘High-fat dairy products’ clusters, and lower fasting glucose than the ‘High-fat dairy products’ cluster (P ≤ 0.05). No differences were found in 2-hour glucose. With respect to inflammation, the ‘Healthy foods’ cluster had lower IL-6 than the ‘Sweets and desserts’ and ‘High-fat dairy products’ clusters, and no differences were seen in CRP or TNF-α.

Conclusions

A dietary pattern high in lowfat dairy products, fruit, whole grains, poultry, fish and vegetables may be associated with greater insulin sensitivity and lower systemic inflammation in older adults.

Dietary fat and cholesterol and risk of cardiovascular disease in older adults: the Health ABC Study

BACKGROUND AND AIMS

Although dietary fats and cholesterol have previously been associated with risk of cardiovascular disease (CVD) in middle-aged populations, less is known among older adults. The purpose of this study was to determine the association between dietary fats, cholesterol, and eggs and CVD risk among community-dwelling adults aged 70-79 in the Health, Aging and Body Composition Study.

METHODS AND RESULTS

Diet was assessed using an interviewer-administered 108-item food frequency questionnaire (n=1941). CVD events were defined as a confirmed myocardial infarction, coronary death, or stroke. Relative rates of CVD over 9 years of follow-up were estimated using Cox proportional hazards models. During follow-up, there were 203 incident cases of CVD. There were no significant associations between dietary fats and CVD risk. Dietary cholesterol (HR (95% CI): 1.47 (0.93, 2.32) for the upper vs. lower tertile; P for trend, 0.10) and egg consumption (HR (95% CI): 1.68 (1.12, 2.51) for 3+/week vs. <1/week; P for trend, 0.01) were associated with increased CVD risk. However, in sub-group analyses, dietary cholesterol and egg consumption were associated with increased CVD risk only among older adults with type 2 diabetes (HR (95% CI): 3.66 (1.09, 12.29) and 5.02 (1.63, 15.52), respectively, for the upper vs. lower tertile/group).

CONCLUSIONS

Dietary cholesterol and egg consumption were associated with increased CVD risk among older, community-dwelling adults with type 2 diabetes. Further research on the biological mechanism(s) for the increased CVD risk with higher dietary cholesterol and frequent egg consumption among older adults with diabetes is warranted.

Plasma F2-isoprostane level and cognitive function over eight years in non-demented older adults: Findings from the Health ABC Study

F2-isoprostanes (F2-IsoP) are reportedly increased in dementia patients, and are considered a reliable biomarker of oxidation. However, few studies have examined the predictive value of peripheral F2-IsoP levels in non-demented older adults. This study assesses the association between plasma F2-IsoP and change in cognitive function in non-demented elderly over eight years. Plasma F2-IsoP was measured by gas chromatography-mass spectrometry in a biracial cohort of 726 elderly men and women. Digit Symbol Substitution test and the Modified Mini-Mental State Exam were administered over time. No association was found between F2-IsoP tertile and baseline or change (slope) in cognitive function over eight years. Plasma F2-IsoP is not a valuable biomarker in predicting cognitive change over years in non-demented older adults.

Prevalence and correlates of diabetes in South asian indians in the United States: findings from the metabolic syndrome and atherosclerosis in South asians living in america study and the multi-ethnic study of atherosclerosis

BACKGROUND

Individuals from South Asia have high diabetes prevalence despite low body weight. We compared the prevalence of diabetes among South Asian Indians with other U.S. ethnic groups and explored correlates of diabetes.

METHODS

This was a cross-sectional study of 150 South Asian Indians (ages 45-79) in California, using similar methods to the Multi-Ethnic Study of Atherosclerosis (MESA). Type 2 diabetes was classified by fasting plasma glucose (FPG) >or=126 mg/dL, 2-h postchallenge glucose >or=200 mg/dL, or use of hypoglycemic medication.

RESULTS

A total of 29% of Asian Indians had diabetes, 37% had prediabetes, and 34% had normal glucose tolerance. After full adjustment for covariates, Indians still had significantly higher odds of diabetes compared to whites and Latinos, but not significantly different from African Americans and Chinese Americans in MESA: Indians [odds ratio (OR), 1.0], whites [OR, 0.29; 95% confidence interval (CI), 0.17-0.49], Latinos (OR, 0.59; CI, 0.34-1.00) African Americans (OR, 0.77; CI 0.45-1.32), Chinese Americans (OR, 0.78, CI, 0.45-1.32). Variables associated with prediabetes or diabetes among Indians included hypertension, fatty liver, visceral adiposity, microalbuminuria, carotid intima media thickness, and stronger traditional Indian beliefs.

CONCLUSIONS

Indian immigrants may be more likely to have diabetes than other U.S. ethnic groups, and cultural factors may play a role, suggesting that this is a promising area of research.

Urinary incontinence and pelvic floor dysfunction in Asian-American women

OBJECTIVE

The objective of the study was to describe the prevalence, risk factors, and impact of urinary incontinence and other pelvic floor disorders among Asian-American women.

STUDY DESIGN

This was a population-based cohort study of older women randomly selected from age and race strata.

RESULTS

Weekly urinary incontinence was reported by 65 of 345 Asian women (18%), with stress and urge incontinence being approximately equally common. In multivariate analysis, higher body mass index (greater than 25 kg/m2) was associated with both stress incontinence (odds ratio 4.90, 95% confidence interval 1.76 to 13.68) and urge incontinence (odds ratio 2.49, 95% confidence interval 1.01 to 6.16) in Asians. Hysterectomy was a significant risk factor for stress incontinence (odds ratio 2.79, 95% confidence interval 1.03 to 7.54). Only 34% of Asian women with weekly urinary incontinence reported ever having sought treatment. Pelvic floor exercises were the most common form of treatment, being used by 29% of Asian women with weekly incontinence. Asians were less likely then white women to report anal incontinence (21% versus 29%, P = .007), although this difference became nonsignificant after adjusting for differences in risk factors.

CONCLUSION

Asian women share some risk factors for stress and urge urinary incontinence with white women. Urinary incontinence is associated with anal incontinence among Asian women.

PPAR-gamma Pro12Ala genotype and risk of cognitive decline in elders

BACKGROUND

The Pro12Ala polymorphism of peroxisome proliferator-activated receptor-gamma (PPAR-gamma) has been associated with decreased risk of diabetes and obesity, both disorders linked to cognitive impairment. We tested whether this polymorphism is associated with cognition.

METHODS

Two thousand nine hundred sixty-one participants (mean age, 74.1; 41% Black; 52% women) were administered the Modified Mini-Mental State Examination (3MS) and Digit Symbol Substitution Test (DSST) at baseline and 4 year follow-up. Test scores were adjusted for age, sex, education, cerebrovascular disease, depression and APOE genotype and additionally for race. We determined the association between Ala allele and development of cognitive decline (3MS decline of > or = 5 points).

RESULTS

At baseline, unadjusted scores on both cognitive tests were higher for Ala carriers compared to non-carriers (3MS, 94.2 versus 92.5, p<0.001; DSST, 40.2 versus 34.5, p<0.001). Similarly, follow-up scores were higher for Ala carriers. Multivariable adjustment led to similar results; additional adjustment for race attenuated the baseline 3MS results. After 4 years, 17.5% of Ala carriers developed cognitive decline compared to 25% among non-carriers (unadjusted OR=0.61; 95%CI, 0.46-0.82; adjusted OR=0.75; 95%CI, 0.55-1.02). Further adjustment for metabolic variables including fasting blood glucose and lipid level did not change the results.

CONCLUSIONS

The PPAR-gamma Ala12 allele carriers may have less risk of developing cognitive decline.

Glycemia and cognitive function in older adults using glucose-lowering drugs

OBJECTIVES

In experimental studies, both high and low levels of plasma glucose are associated with cognitive impairment. In populations, less is known about the relationship between glycemia and cognitive function, especially in persons using glucose-lowering drugs.

DESIGN

A cross-sectional study of 378 high-functioning black and white men and women aged 70 to 79 participating in the Health, Aging, and Body Composition Study (Health ABC) who used glucose-lowering medications. Glycemic measures included fasting plasma glucose (FPG) and glycosylated hemoglobin (HbA1c). Cognitive function was assessed using the Modified Mini-Mental State Examination (3MS) and the Digit Symbol Substitution Test (DSS) at the same examination visit in which the glycemic measures were determined.

SETTING

Memphis, Tennessee and Pittsburgh, Pennsylvania.

RESULTS

We observed an "inverted-U" relationship (p =.0025 for 3MS, p=.0277 for DSS) between FPG (range 47 - 366 mg/dl) and performance on these two tests. The fasting plasma glucose levels associated with the highest score on the 3MS was 180 mg/dl and 135 mg/dl for the DSS. There was a monotonic inverse relationship between HbA1c and performance on 3MS and DSS without evidence of a threshold effect.

CONCLUSION

Our findings suggest that older adults who are treated for diabetes may experience a small degree of cognitive impairment within the recommended fasting glucose levels, yet measures of long-term glycemic control support tight glycemic control. Given the high prevalence of diabetes and the common use of glucose-lowering drugs in older adults, further studies are needed to elucidate these relationships.

Low subcutaneous thigh fat is a risk factor for unfavourable glucose and lipid levels, independently of high abdominal fat. The Health ABC Study

AIMS

We investigated whether low subcutaneous thigh fat is an independent risk factor for unfavourable glucose and lipid levels, and whether these associations differ between sexes, and between white and black adults. Our secondary aim was to investigate which body composition characteristics (lean tissue, fat tissue) are reflected by anthropometric measures (waist and thigh circumference).

METHODS

Anthropometric measurements and computed tomography of the abdomen and of the thigh were performed for all participants of the Health, Aging and Body Composition Study, who were aged 70-79 years. Fasting glucose, triglycerides and HDL-cholesterol, and 2-h postload glucose were determined.

RESULTS

After excluding those already diagnosed with diabetes or dyslipidaemia, we analysed data from 2,106 participants. After adjustment for abdominal subcutaneous and visceral fat, and intermuscular thigh fat, larger thigh subcutaneous fat area was statistically significantly associated with lower ln-transformed triglycerides [standardised beta (95% CI) -0.12 (-0.20 to -0.04) in men and -0.13 (-0.21 to -0.05) in women] and higher ln-HDL-cholesterol [0.10 (0.02 to 0.19) and 0.09 (0.01 to 0.18), respectively]. The associations with lower glucose levels were strong in men [-0.11 (-0.20 to -0.02) for fasting and -0.14 (-0.23 to -0.05) for postload glucose], but not statistically significant in women [-0.02 (-0.10 to 0.07) and -0.04 (-0.13 to 0.05), respectively]. There were no differences in the associations between white and black persons. Waist circumference was more strongly associated with abdominal subcutaneous fat, and this association became stronger with increasing BMI, whereas the association with visceral fat became weaker. Thigh circumference was equally dependent on thigh fat and thigh muscle in men, whereas in women the fat component was the main contributor.

CONCLUSION

Larger subcutaneous thigh fat is independently associated with more favourable glucose (in men) and lipid levels (in both sexes) after accounting for abdominal fat depots, which are associated with unfavourable glucose and lipid levels. Anthropometric measures reflect different fat depots at different levels of BMI at the abdomen, and reflect both fat and lean tissue at the thigh. These results emphasise the importance of accurate measures of regional body composition when investigating potential health risks.

Urinary incontinence in elderly women: findings from the Health, Aging, and Body Composition Study

OBJECTIVE

To estimate the prevalence of and risk factors for stress and urge incontinence in a biracial sample of well-functioning older women.

METHODS

We performed a cross-sectional analysis of 1,584 white and black women, aged 70-79 years, enrolled in a longitudinal cohort study. Participants were asked about incontinence, medical problems, and demographic and reproductive characteristics and underwent physical measurements. Using multivariable logistic regression, we compared women reporting at least weekly incontinence with those without incontinence.

RESULTS

Overall, 21% reported incontinence at least weekly. Of these, 42% reported predominantly urge incontinence, and 40% reported stress. Nearly twice as many white women as black women reported weekly incontinence (27% versus 14%, P <.001). Factors associated with urge incontinence included white race (odds ratio [OR] 3.1, 95% confidence interval [CI] 2.0-4.8), diabetes treated with insulin (OR 3.5, 95% CI 1.6-7.9), depressive symptoms (OR 2.7, 95% CI 1.4-5.3), current oral estrogen use (OR 1.7, 95% CI 1.1-2.6), arthritis (OR 1.7, 95% CI 1.1-2.6), and decreased physical performance (OR 1.6 per point on 0-4 scale, 95% CI 1.1-2.3). Factors associated with stress incontinence were chronic obstructive pulmonary disease (OR 5.6, 95% CI 1.3-23.2), white race (OR 4.1, 95% CI 2.5-6.7), current oral estrogen use (OR 2.0, 95% CI 1.3-3.1), arthritis (OR 1.6, 95% CI 1.0-2.4), and high body mass index (OR 1.3 per 5 kg/m2, 95% CI 1.1-1.6).

CONCLUSION

Urinary incontinence is highly prevalent, even in well-functioning older women, whites in particular. Many risk factors differ for stress and urge incontinence, suggesting differing etiologies and prevention strategies.

Diabetes, impaired fasting glucose, and development of cognitive impairment in older women

OBJECTIVE

To investigate the association between diabetes and impaired fasting glucose (IFG) and cognition and risk of developing both dementia and mild cognitive impairment (MCI) in older women.

METHODS

The authors analyzed data from a 4-year randomized trial of raloxifene among 7,027 osteoporotic postmenopausal women (mean age, 66.3 years) at 178 sites. Diabetes was defined by history, fasting blood glucose > or =7.0 mmol/L (> or =126 mg/dL), or use of hypoglycemic agents; IFG was defined as fasting glucose <7.0 mmol/L but >6.11 mmol/L (110 mg/dL); all others were considered to have normal glucose (NG). The main outcome was baseline and 4-year change on five standardized cognitive tests (z scores with lower scores indicating worse performance) and risk of developing clinically significant impairment (dementia, mild cognitive impairment, or very low cognitive score).

RESULTS

A total of 267 (3.8%) women had diabetes and 297 (4.2%) had IFG. Women with IFG had worse baseline cognitive scores compared to women with NG but better scores than diabetics (age-adjusted composite z score based on five tests: NG 0.40, 95% CI 0.30 to 0.49; IFG 0.14, 95% CI -0.36 to 0.64; diabetics -0.78, 95% CI -1.23 to -0.33; p < 0.001). There was greater 4-year decline among diabetics (age and treatment-adjusted composite z score: NG -0.05, 95% CI -0.16 to 0.05; IFG 0.11, 95% CI -0.53 to 0.75; diabetics -1.00, 95% CI -1.50 to -0.50; p = 0.001). Further adjustment for education, race, and depression led to similar results. Risk of developing cognitive impairment among women with IFG or diabetes was increased by almost twofold (age and treatment-adjusted OR = 1.64; 95% CI 1.03 to 2.61 for IFG; OR = 1.79; 95% CI 1.14 to 2.81 for diabetics).

CONCLUSIONS

Diabetic as well as pre-diabetic women have impaired cognitive performance and greater risk of developing cognitive impairment.

Prevention of type 2 diabetes: data from recent trials

All four main studies of lifestyle intervention on diabetes incidence found a clear benefit for diet and exercise intervention compared with usual care. Although the study populations differed by race and ethnicity, the mean BMI, and the intensity of the lifestyle intervention provided, all investigators found substantial diabetes risk reduction with modest weight loss and increased physical activity. Results of these trials give health care providers useful and heartening information to share with patients at risk for diabetes. The challenge remains to find feasible and cost-efficient methods to identify people at risk and to deliver effective lifestyle interventions. Findings from trials of pharmacologic agents such as metformin, acarbose, and troglitazone are encouraging; however, the ADA recommends that drug therapy should not be used routinely to prevent diabetes until more information regarding the cost-effectiveness of such intervention is known [20]. Results from trials that found a lower incidence of diabetes among those randomly assigned to angiotensin-converting enzyme inhibitors, statins, or hormone therapy are intriguing but must be viewed with caution because they are based on post hoc analyses. Because it is difficult to conduct randomized controlled trials of major operative procedures such as bariatric surgery, observational studies that compare surgical interventions for weight loss with traditional weight-loss management may be the best evidence available. These studies have the potential for healthy-person bias in that people who choose bariatric surgery may have other healthy behaviors that are often difficult to measure and control for; such behaviors could account for their lower incidence of diabetes. Undeniably, the best test to diagnose those at high risk for diabetes is not yet known. New strategies that identify those with pre-diabetes and that overcome the limitations of the current tests, particularly the 2-hour post-challenge glucose test, are needed.

Urinary tract infections in postmenopausal women: effect of hormone therapy and risk factors

OBJECTIVE

To assess the effects of hormone therapy on urinary tract infection frequency and to examine potential risk factors.

METHODS

We used data from the Heart and Estrogen/Progestin Replacement Study, a randomized, blinded trial of the effects of hormone therapy on coronary heart disease events among 2763 postmenopausal women aged 44-79 with established coronary heart disease. Participants were randomly assigned to 0.625 mg of conjugated estrogens plus 2.5 mg of medroxyprogesterone acetate or placebo and followed for a mean of 4.1 years. History of physician-diagnosed urinary tract infections and risk factors were assessed by self-report at baseline and each annual visit.

RESULTS

Urinary tract infection frequency was higher in the group randomized to hormone treatment, although the difference was not statistically significant (odds ratio [OR] 1.16, 95% confidence interval [CI] 0.99, 1.37). Statistically significant risk factors for urinary tract infections in multivariable analysis included: women with diabetes on treatment (insulin OR 1.81, 95% CI 1.40, 2.34), oral medications OR 1.44, 95% CI 1.09, 1.90), poor health (OR 1.34, 95% CI 1.14, 1.57), childbirth (OR 1.38, 95% CI 1.00, 1.90), vaginal itching (OR 1.63, 95% CI 1.07, 2.50), vaginal dryness (OR 1.30, 95% CI 1.04, 1.67), and urge incontinence (OR 1.51, 95% CI 1.30, 1.75). Urinary tract infections in the previous year were strongly associated with a single urinary tract infection (OR 7.00, 95% CI 5.91, 8.29) as well as multiple urinary tract infections (OR 18.51, 95% CI 14.27, 24.02).

CONCLUSIONS

Oral hormone therapy did not reduce frequency of urinary tract infections. Potentially modifiable risk factors in postmenopausal women are different from those in younger women, and include diabetes, vaginal symptoms, and urge incontinence.

Identifying pulmonary tuberculosis in patients with negative sputum smear results

BACKGROUND

Clinicians need to decide whether to begin empiric therapy for patients who are suspected of having tuberculosis (TB) but have negative sputum smear results. Culture results may take weeks, and delaying treatment may allow further transmission of disease.

STUDY OBJECTIVE

To identify the clinical, demographic, and radiographic characteristics that identify smear-negative patients who have TB, and to create a TB prediction rule.

DESIGN

Retrospective chart review.

SETTING

University-affiliated public hospital in San Francisco, CA, between 1993 and 1998.

PATIENTS

Forty-seven patients with TB and 141 control patients who were hospitalized with a suspicion of pulmonary TB; all had negative sputum smear results.

MEASUREMENTS AND RESULTS

Demographic, clinical, and radiographic variables were determined by chart review. In multivariate analysis, a positive tuberculin skin test result (odds ratio [OR], 4.8; 95% confidence interval [CI], 2.0 to 11.9) was independently associated with an increased risk of a positive TB culture finding. A radiographic pattern not typical of pulmonary tuberculosis (OR, 0.3; 95% CI, 0.1 to 0.7) and expectoration with cough (OR, 0.3; 95% CI, 0.1 to 0.6) were predictive of a decreased risk. An interaction between HIV seropositivity and mediastinal lymphadenopathy on the chest radiograph was also associated with a positive TB culture result (OR, 7.2; 95% CI, 1.4 to 36.0). The TB prediction score (TPS) was created with widely ranging likelihood ratios that could affect the posterior probability of TB by 30-fold.

CONCLUSION

The TPS put into context with the overall prevalence of TB in a given area may help clinicians decide if a patient with negative sputum smear results should start empiric antituberculous therapy or wait for culture results. These results need prospective validation.