Confirming glycemic status in the Diabetes Prevention Program: implications for diagnosing diabetes in high risk adults.

AIMS: To examine the ability of fasting plasma glucose (FPG) and/or 2-h glucose to confirm diabetes and to determine the proportion of participants with HbA1c ≥6.5%. METHODS: Diabetes confirmation rates were calculated after a single elevated FPG and/or 2-h glucose on an oral glucose tolerance test (OGTT) using a confirmatory OGTT performed within 6 weeks. RESULTS: 772 (24%) participants had elevated FPG or 2-h glucose on an OGTT that triggered a confirmation visit. There were 101 triggers on FPG alone, 574 on 2-h glucose alone, and 97 on both. Only 47% of participants who triggered had confirmed diabetes. While the confirmation rate for FPG was higher than that for 2-h glucose, the larger number of 2-h glucose triggers resulted in 87% of confirmed cases triggering on 2-h glucose. Confirmation rates increased to 75% among persons with FPG ≥126 mg/dl and HbA1c ≥6.5%. CONCLUSIONS: Only half of the persons with elevated FPG and IGT were subsequently confirmed to have diabetes. At current diagnostic levels, more persons trigger on 2-h glucose than on FPG, but fewer of these persons have their diagnoses confirmed. In individuals with FPG ≥126 mg/dl and HbA1c ≥6.5%, the confirmation rate was increased.

Metabolic syndrome and left ventricular hypertrophy in the prediction of cardiovascular events: the Strong Heart Study.

BACKGROUND AND AIMS: Metabolic syndrome (MetS) is associated with increased prevalence of echocardiographic LV hypertrophy (LVH), a potent predictor of cardiovascular (CV) outcome. Whether MetS increases risk of CV events independently of presence of LVH has never been investigated. It is also unclear whether LVH predicts CV risk both in the presence and absence of MetS. METHODS AND RESULTS: Participants in the 2nd Strong Heart Study examination without prevalent coronary heart disease, congestive heart failure or renal insufficiency (plasma creatinine >2.5mg/dL) were studied (n=2758; 1746 women). MetS was defined by WHO criteria. Echocardiographic LV hypertrophy was defined using population-specific cut-point value for LV mass index (>47.3g/m(2.7)). After controlling for age, sex, LDL-cholesterol, smoking, plasma creatinine, diabetes, hypertension and obesity, participants with MetS had greater probability of LVH than those without MetS (OR=1.55 [1.18-2.04], p<0.002). Adjusted hazard of composite fatal and non-fatal CV events was greater when LVH was present, in participants without (HR=2.03 [1.33-3.08]) or with MetS (HR=1.64 [1.31-2.04], both p<0.0001), with similar adjusted population attributable risk (12% and 14%). After adjustment for LVH, risk of incident CV events remained 1.47-fold greater in MetS (p<0.003), an effect, however, that was not confirmed when diabetic participants were excluded. CONCLUSION: LVH is a strong predictor of composite 8-year fatal and non-fatal CV events either in the presence or in the absence of MetS and accounts for a substantial portion of the high CV risk associated with MetS.

Ankle brachial index combined with Framingham Risk Score to predict cardiovascular events and mortality: a meta-analysis.

CONTEXT: Prediction models to identify healthy individuals at high risk of cardiovascular disease have limited accuracy. A low ankle brachial index (ABI) is an indicator of atherosclerosis and has the potential to improve prediction. OBJECTIVE: To determine if the ABI provides information on the risk of cardiovascular events and mortality independently of the Framingham risk score (FRS) and can improve risk prediction. DATA SOURCES: Relevant studies were identified. A search of MEDLINE (1950 to February 2008) and EMBASE (1980 to February 2008) was conducted using common text words for the term ankle brachial index combined with text words and Medical Subject Headings to capture prospective cohort designs. Review of reference lists and conference proceedings, and correspondence with experts was conducted to identify additional published and unpublished studies. STUDY SELECTION: Studies were included if participants were derived from a general population, ABI was measured at baseline, and individuals were followed up to detect total and cardiovascular mortality. DATA EXTRACTION: Prespecified data on individuals in each selected study were extracted into a combined data set and an individual participant data meta-analysis was conducted on individuals who had no previous history of coronary heart disease. RESULTS: Sixteen population cohort studies fulfilling the inclusion criteria were included. During 480,325 person-years of follow-up of 24,955 men and 23,339 women, the risk of death by ABI had a reverse J-shaped distribution with a normal (low risk) ABI of 1.11 to 1.40. The 10-year cardiovascular mortality in men with a low ABI (< or = 0.90) was 18.7% (95% confidence interval [CI], 13.3%-24.1%) and with normal ABI (1.11-1.40) was 4.4% (95% CI, 3.2%-5.7%) (hazard ratio [HR], 4.2; 95% CI, 3.3-5.4). Corresponding mortalities in women were 12.6% (95% CI, 6.2%-19.0%) and 4.1% (95% CI, 2.2%-6.1%) (HR, 3.5; 95% CI, 2.4-5.1). The HRs remained elevated after adjusting for FRS (2.9 [95% CI, 2.3-3.7] for men vs 3.0 [95% CI, 2.0-4.4] for women). A low ABI (< or = 0.90) was associated with approximately twice the 10-year total mortality, cardiovascular mortality, and major coronary event rate compared with the overall rate in each FRS category. Inclusion of the ABI in cardiovascular risk stratification using the FRS would result in reclassification of the risk category and modification of treatment recommendations in approximately 19% of men and 36% of women. CONCLUSION: Measurement of the ABI may improve the accuracy of cardiovascular risk prediction beyond the FRS.

Assessing the impact of different imputation methods on serial measures of renal function: the Strong Heart Study.

Missing data are a common problem in epidemiologic studies. This study had two aims: (a) to determine which method for imputing missing renal function data provides estimates closest to those made with complete data and (b) to determine which measure of renal function better estimates cardiovascular disease (CVD) risk. For these analyses, a subset of Strong Heart Study participants with complete data for renal function was identified. Data were randomly dropped from this complete set at three rates: 30, 45, and 60%. Five common techniques for handling missing data were compared: imputation using the mean, adjacent value (AV), single imputation, multiple imputation, and listwise deletion. Differences between the imputed sets and the complete set were determined for each method. Imputation methods were used to fill in missing values for serum creatinine (Scr) in one model and estimated glomerular filtration rate (eGFR) in another. For both Scr and eGFR, the AV method provided the most favorable results in predicting CVD risk, regardless of the rate of missing data.

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.

Diabetes mellitus and impaired fasting glucose in Alaska Eskimos: the Genetics of Coronary Artery Disease in Alaska Natives (GOCADAN) study.

AIMS/HYPOTHESIS: We aimed to: (1) define the prevalence of type 2 diabetes and IFG in Eskimos in Norton Sound, Alaska; (2) determine correlates of prevalent diabetes in this population; and (3) compare the prevalence of diabetes in the Genetics of Coronary Artery Disease in Alaska Natives (GOCADAN) Study with other samples of Eskimos, Inuit, American Indians and US blacks, whites and Mexican Americans. METHODS: The GOCADAN Study enrolled 1,214 participants >or=18 years who were members of extended pedigrees from the Norton Sound region of Alaska. Diagnosed type 2 diabetes was based on reported use of insulin or hypoglycaemic medications and a medication inventory. Fasting glucose measurements were obtained to ascertain IFG status and undiagnosed diabetes according to American Diabetes Association (ADA) criteria. OGTTs were performed to ascertain diabetes according to the World Health Organization (WHO) definition. We used logistic regression analysis to model factors that were significantly associated with odds of prevalent ADA diabetes. RESULTS: The prevalences of ADA diabetes and IFG were 3.8% (5.0% of women; 2.2% of men) and 15.6% (13.9% of women; 17.7% of men), respectively. In the subset of 787 participants who took the OGTT, the prevalences of ADA and WHO diabetes were 5.1 and 6.9%, respectively. The adjusted odds of ADA diabetes was 2.8 times higher in participants meeting Adult Treatment Panel III criteria for abdominal obesity than in those who did not. The statistically significant sex-related difference in diabetes prevalence did not persist in multivariable analyses. CONCLUSIONS/INTERPRETATION: Alaska Eskimos have a low prevalence of type 2 diabetes. The high prevalence of IFG indicates that diabetes may become increasingly problematic in this population. Abdominal obesity in women may help explain why diabetes prevalence differs according to sex.

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.

Effects of glycaemic control on cardiovascular disease in diabetic American Indians: the Strong Heart Study.

AIMS: Diabetes increases the risk of cardiovascular disease (CVD). Only part of this excess risk is explained by diabetes-associated hypertension, obesity, and lipid disorders. Poor glycaemic control may help explain the residual CVD risk. The aim of this study was to determine whether variations in glycaemic control are associated with CVD risk in diabetic individuals. METHODS: We examined longitudinal data from the Strong Heart Study, a population-based study of CVD and its risk factors among American Indians (a population with a high prevalence of diabetes). Diabetes was defined using the 1998 World Health Organization criteria: fasting plasma glucose >/= 126 mg/dl or 2-h plasma glucose >/= 200 mg/dl. American Diabetes Association guidelines for glycaemic control were used: good, A(1c) < 7%; fair, 7-7.9%; and poor, >/= 8%. The analysis was based on data from diabetic individuals with no CVD at baseline. RESULTS: During 9 years of follow-up, 494 of the 2011 diabetic participants developed CVD. Although Cox multivariate regression modelling showed dose-response effects of glycaemic control on overall CVD and coronary heart disease (CHD) incidence, the relationships were weakened when adjusted for confounding variables. Kaplan-Meier analysis, however, showed that diabetic individuals with poor baseline glycaemic control had significantly increased proportions of overall CVD and CHD (P = 0.001) during the 9 years of follow-up, compared with those who had good or fair control. CONCLUSIONS: These findings highlight the importance of risk factors, such as high blood pressure and dyslipidaemia, in increasing CVD risk in those with diabetes.

Widespread musculoskeletal pain and the progression of disability in older disabled women.

BACKGROUND: Widespread musculoskeletal pain is a poorly understood but common problem in older adults. Little is known about the progression of disability related to this condition. OBJECTIVE: To determine whether widespread musculoskeletal pain increases the risk for worsening disability in older women with disabilities. DESIGN: Prospective cohort study. SETTING: The Women's Health and Aging Study. PARTICIPANTS: 1002 community-dwelling women 65 years of age or older with disability. MEASUREMENTS: Widespread musculoskeletal pain was defined as pain in the upper and lower extremities and axial pain with moderate or severe pain in at least one of the three regions. Worsening disability was defined as progression from no or mild difficulty to severe difficulty or inability to perform activities of daily living (ADLs), walk one-quarter mile, or lift 10 lbs. RESULTS: At baseline, 24% of participants had widespread pain and 25% had no pain or only mild pain in a single site. Women with widespread pain were 2.5 to 3.5 times more likely to have severe difficulty with ADLs, walking, or lifting at baseline compared with women who had no or mild pain. In women without severe difficulty initially, widespread pain nearly doubled the risk for progression to severe difficulty in each of the tasks, after adjustment for age, body mass index, comorbid illness, and other confounders. CONCLUSION: Widespread musculoskeletal pain is frequent among community-dwelling older women with disability and appears to predict the progression of disability. Efforts to better understand the cause of this pain and its treatment might reduce the overall burden of disability.

Type 2 diabetes in older well-functioning people: who is undiagnosed? Data from the Health, Aging, and Body Composition study.

OBJECTIVE: To assess, in an older population, the prevalence of diagnosed and undiagnosed diabetes, the number needed to screen (NNTS) to identify one individual with undiagnosed diabetes, and factors associated with undiagnosed diabetes. RESEARCH DESIGN AND METHODS: Socioeconomic and health-related factors were assessed at the baseline examination of the Health, Aging, and Body Composition (Health ABC) Study, a cohort of 3,075 well-functioning people aged 70-79 years living in Memphis, Tennessee and Pittsburgh, Pennsylvania (42% blacks and 48% men). Diabetes was defined according to the 1985 World Health Organization criteria (fasting glucose > or =7.8 mmol/l or 2-h glucose > or =11.1 mmol/l) and the 1997 American Diabetes Association criteria (fasting glucose > or =7.0 mmol/l). RESULTS: The prevalence of diagnosed and undiagnosed diabetes was 15.6 and 8.0%, respectively, among all participants (NNTS 10.6), 13.9 and 9.1% among white men (NNTS 9.5), 7.8 and 7.4% among white women (NNTS 12.4), 22.7 and 9.1% among black men (NNTS 8.5), and 21.6 and 6.2% among black women (NNTS 12.6). In multivariate analyses, compared with individuals without diabetes, individuals with undiagnosed diabetes were more likely to be men and were more likely to have a history of hypertension, higher BMI, and larger waist circumference. NNTS was lowest in men (9.1), individuals with hypertension (8.7), individuals in the highest BMI quartile (6.9), and individuals in the largest waist circumference quartile (6.8). CONCLUSIONS: In approximately one-third of all older people with diabetes, the condition remains undiagnosed. Screening for diabetes may be more efficient among men and individuals with hypertension, high BMI, and large waist circumference.

The relation of markers of inflammation to the development of glucose disorders in the elderly: the Cardiovascular Health Study.

Several studies suggest that inflammation plays a role in the pathogenesis of some glucose disorders in adults. We tested this hypothesis in a longitudinal cohort study of older individuals who had normal fasting glucose (FG) values at baseline. We compared the baseline levels of six inflammatory markers in participants who had developed glucose disorders at follow-up with those of participants whose FG remained normal at follow-up. Participants were members of the Cardiovascular Health Study, a prospective study of risk factors for cardiovascular disease in adults > or =65 years. All 5,888 participants had baseline testing, including FG and markers of inflammation: white blood cell and platelet counts and albumin, fibrinogen, C-reactive protein (CRP), and factor VIIIc levels. At 3-4 years of follow-up, 4,481 (84.5%) of those who were alive had FG levels retested. Participants who developed diabetes (n = 45) had higher median levels of CRP at baseline than those who remained normoglycemic. On multivariate analysis, those with elevated CRP levels (75th percentile [2.86 mg/l] vs. 25th percentile [0.82 mg/l]) were 2.03 times (95% confidence intervals, 1.44-2.86) more likely to have diabetes on follow-up. Adjustment for confounders and other inflammatory markers did not appreciably change this finding. There was no relationship between the development of diabetes and other markers of inflammation. Inflammation, as measured by CRP levels, is associated with the development of diabetes in the elderly. Understanding the role of inflammation in the pathogenesis of glucose disorders in this age-group may lead to better classification and treatment of glucose disorders among them.

Prevalence and clinical implications of American Diabetes Association-defined diabetes and other categories of glucose dysregulation in older adults: the health, aging and body composition study.

Using data on history of diabetes, fasting glucose (FG) and the oral glucose tolerance test (OGTT), the authors contrasted cardiovascular disease (CVD) risk factors (body mass index, blood pressure, lipids and glycated hemoglobin) in 3052 African-American and White adults aged 70-79 in mutually exclusive categories of diagnosed diabetes, undiagnosed diabetes defined by the American Diabetes Association (ADA), isolated post-challenge hyperglycemia (IPH; FG < 126 mg/dL and 2 h post-OGTT > or = 200 mg/dL), impaired fasting glucose (IFG; FG > or = 110 but < 126 mg/dL), and individuals who were non-diabetic by both ADA and World Health Organization (WHO) criteria (FG < 126 mg/dL and 2 h post-challenge glucose < 200 mg/dL). The prevalence of diagnosed diabetes, undiagnosed ADA diabetes and IPH were 15.2, 3.8 and 4.7%, respectively, with more diagnosed and undiagnosed ADA diabetes in African-Americans than Whites. Compared to mean glycated hemoglobin (HbA(1c)) among ADA/WHO non-diabetic individuals (6.0%), HbA(1c) was substantially higher in the diagnosed diabetes and undiagnosed ADA diabetes groups (8.0% and 7.7%), but not in the IPH group (6.3%). The diagnosed and undiagnosed ADA diabetic groups had worse CVD risk factor profiles than the ADA/WHO non-diabetic group. IPH subjects had elevated levels of some CVD risk factors, but differences were more modest than those for the diabetic groups. Among people with IPH, those who also had IFG had worse CVD profiles than those with IPH alone. Although the OGTT may identify additional adults with more CVD risk factors than normals, these differences appear to be clustered among those who also have IFG.

Age 85+ years accelerates large-fiber peripheral nerve dysfunction and diabetes contributes even in the oldest-old: the Women's Health and Aging Study.

BACKGROUND: Both diabetes mellitus and advancing age are associated with peripheral nerve dysfunction (PND). However, the independent and potentially synergistic effects of these factors in old age are poorly described, especially among the oldest-old and among people with an existing disability. METHODS: A total of 894 women aged 65+ years participating in the Women's Health and Aging Study received a baseline home interview and clinical examination during which PND was evaluated by the Vibratron II. Age and diabetes were examined in relation to the level of PND (normal, mild, moderate, or severe). Height, alcohol consumption, smoking, report of neurologic symptoms, and diabetes duration were examined as potential confounders. RESULTS: Eighteen percent of the sample reported diabetes, 42% had normal nerve function, and 23.9%, 14.5%, and 19.5% had mild, moderate, and severe PND, respectively. Women aged 85+ years had 6.5, 7.5, and 13.3 times the odds of mild, moderate, and severe PND relative to women aged 65-74 years, adjusted for diabetes and height. Women who reported diabetes had 1.8, 2.4, and 1.6 times the risk of mild, moderate, and severe PND relative to those who did not, adjusted for age and height. No interaction between age and diabetes was observed. CONCLUSIONS: Age is strongly associated with decrements in large-fiber peripheral nerve function in disabled women aged 65+ years, with greatly accelerated risk among those aged 85+ years. Despite the overwhelmingly strong effects of advancing age on PND in this cohort, diabetes remains a significant correlate of PND. Future studies may determine whether prevention or control of diabetes is effective in reducing the occurrence of PND in old age and whether a reduction in PND will translate into reduced disability in this age group.

Independent effects of peripheral nerve dysfunction on lower-extremity physical function in old age: the Women's Health and Aging Study.

OBJECTIVE: To determine the role of peripheral nerve dysfunction (PND) in the disablement pathway. RESEARCH DESIGN AND METHODS: Vibration perception threshold (VPT) was measured in 894 women aged > or = 65 years, and those with normal peripheral nerve function and with mild, moderate, and severe PND were identified. Lower-extremity impairments included quadriceps strength (kilograms) and three progressively difficult balance tasks (able/unable). Functional limitations included rising from a chair (able/unable) and usual pace and fast-paced walking speeds (meters/second). Level of PND was related to impairments and functional limitations in linear and logistic regression models that controlled for potentially confounding factors, including reported diabetes. RESULTS: Level of PND was associated with impaired balance (adjusted odds ratios: 2.21, 1.95, and 3.02 for mild, moderate, and severe PND, respectively, relative to normal, P < 0.05). PND was also associated with decrements in both usual and fast-paced walking speeds (-0.08, -0.08, and -0.15 m/s for usual pace and -0.13, -0.12, and -0.24 m/s for fast-paced walking speed for women with mild, moderate, and severe PND, respectively; P < 0.01 for all). Reported diabetes was not associated with these outcomes in the presence of PND. Some, but not all, of the association between PND and functional limitations was explained by the relationship between PND and impairments. CONCLUSIONS: PND is significantly associated with both lower-extremity impairments and functional limitations in older women, and PND appears to have independent effects on functional limitations. The independent effect of diabetes on these outcomes may be limited when PND is considered. Further research is needed to determine if PND is causally related to disability in old age.

Genotypes and phenotypes for apolipoprotein E and Alzheimer disease in the Honolulu-Asia aging study.

BACKGROUND: The utility of apolipoprotein E (ApoE) type as an indicator of genetic susceptibility to Alzheimer disease (AD) depends on the reliability of typing. Although ApoE protein isoform phenotyping is generally assumed equivalent to genotyping from DNA, phenotype-genotype differences have been reported. METHODS: ApoE genotype and phenotype results were examined for 3564 older (ages 71-93 years) Japanese-American male participants of the Honolulu-Asia Aging Study, an ongoing population-based study of aging and dementia. RESULTS: Both methods demonstrated similar associations of ApoE type with AD: a direct association with ApoE4 and a less dramatic inverse association ApoE2. Advanced age did not appear to influence the ApoE4-AD association. The association with AD among ApoE4 homozygotes [odds ratio (OR) = 14.7] was higher than expected based on an observed OR of 2.0 in heterozygotes. Phenotype-genotype nonconcordance was more frequent for ApoE2 than for ApoE4. The ApoE2 phenotype occurred at a frequency of 7.9% vs a genotype frequency of 4.9%, corresponding to a probability of 56% that an individual with ApoE2 phenotype had the same genotype. CONCLUSIONS: Whereas E4 and E2 phenotypes and genotypes were comparably associated with AD, neither method would be expected to substantially improve the efficiency of case finding in the context of population screening beyond prediction based on age and education. Nonconcordance of phenotype and genotype was substantial for E2 and modest for E4 in this population. The ApoE4-AD association was independent of age.

Gender differences in disability: evidence and underlying reasons.

Women have greater longevity than men and represent a larger proportion of the expanding older population. Several health, disease, behavioral and sociodemographic factors contribute to the higher prevalence of disability in women compared to men. This paper presents a review of methodologic and epidemiologic considerations important to our understanding the gender differences in the prevalence of disability, and discusses underlying causes for these differences. Compared to men, women have a longer duration of life lived with disability, in part due to higher prevalence of non-fatal chronic conditions, constitutional factors such as lower muscle strength and lower bone density, and higher rates of life-style factors such as sedentary behavior and obesity. Several of these factors are modifiable, and provide important targets for researchers, clinicians, and public health practitioners in their efforts to reduce the burden of disability in the older population.

Relation of weight gain and weight loss on subsequent diabetes risk in overweight adults.

STUDY OBJECTIVE: To determine whether long term weight gain and weight loss are associated with subsequent risk of type 2 diabetes in overweight, non-diabetic adults. DESIGN: Prospective cohort. Baseline overweight was defined as BMI>/=27.3 for women and BMI>/=27. 8 for men. Annual weight change (kg/year) over 10 years was calculated using measured weight at subjects' baseline and first follow up examinations. In the 10 years after measurement of weight change, incident cases of diabetes were ascertained by self report, hospital discharge records, and death certificates. SETTING: Community. PARTICIPANTS: 1929 overweight, non-diabetic adults. MAIN RESULTS: Incident diabetes was ascertained in 251 subjects. Age adjusted cumulative incidence increased from 9.6% for BMI<29 to 26. 2% for BMI>/=37. Annual weight change over 10 years was higher in subjects who become diabetic compared with those who did not for all BMI<35. Relative to overweight people with stable weight, each kg of weight gained annually over 10 years was associated with a 49% increase in risk of developing diabetes in the subsequent 10 years. Each kg of weight lost annually over 10 years was associated with a 33% lower risk of diabetes in the subsequent 10 years. CONCLUSIONS: Weight gain was associated with substantially increased risk of diabetes among overweight adults, and even modest weight loss was associated with significantly reduced diabetes risk. Minor weight reductions may have major beneficial effects on subsequent diabetes risk in overweight adults at high risk of developing diabetes.

American Diabetes Association diabetes diagnostic criteria, advancing age, and cardiovascular disease risk profiles: results from the Third National Health and Nutrition Examination Survey.

OBJECTIVE: To evaluate age-specific effects on diabetes prevalence estimates resulting from the American Diabetes Association (ADA) recommendation against use of the oral glucose tolerance test (OGTT), we contrasted the prevalence of two mutually exclusive groups: undiagnosed diabetes according to ADA criteria (no report of diabetes and fasting glucose [FG] > or =126 mg/dl) and isolated postchallenge hyperglycemia (IPH) (FG <126 mg/dl and OGTT > or =200 mg/dl), a group designated to have diabetes by World Health Organization (WHO) criteria but not ADA criteria. RESEARCH DESIGN AND METHODS: The weighted age-specific ratios of undiagnosed diabetes:IPH were calculated for 2,844 subjects aged 40-74 years without reported diabetes who had both FG and OGTT. A ratio > 1.0 indicated that the proportion of undiagnosed diabetes was greater than that of IPH. Mean levels of HbA1c and cardiovascular disease (CVD) risk factors were contrasted among people with undiagnosed diabetes and IPH and those without either abnormality ("nondiabetic"). RESULTS: Both undiagnosed diabetes and IPH increased with age, but age-specific undiagnosed diabetes:IPH ratios decreased from 5.49 in the 40-44 age-group to 0.77 in the 70-74 age-group. Regression analysis showed a significant (P = 0.006) negative association between age and these ratios. Mean HbA1c was 7.1% in the undiagnosed diabetes group and differed significantly from that of the IPH and nondiabetic groups (5.6 and 5.3%, respectively). Individuals with undiagnosed diabetes had less favorable triglycerides, BMI, and HDL cholesterol compared with people with IPH. CONCLUSIONS: Compared with WHO criteria, the ADA criteria underestimate glucose abnormalities more with increasing age. However, compared to those with undiagnosed diabetes, individuals with IPH had a mean HbA1c level that is considered in the nondiabetic range, and this group had significantly more favorable levels of several key CVD risk factors. These findings suggest that the ADA criteria, although underestimating the abnormalities of postchallenge hyperglycemia that occur frequently with increasing age, appear to be effective at identifying a group of individuals with both unfavorable CVD risk factor profiles and evidence of long-term exposure to hyperglycemia.

Waist circumference and sagittal diameter reflect total body fat better than visceral fat in older men and women. The Health, Aging and Body Composition Study.

The validity of waist circumference and sagittal diameter as surrogate measures of visceral fat were assessed using preliminary cross-sectional data from the Health, Aging and Body Composition Study, a cohort of 3,075 men and women aged 70-79. Weight, body mass index, waist circumference, waist/thigh ratio, and sagittal diameter were compared by correlation, graphical analysis, and regression to total body fat as measured by dual-energy X-ray absorptiometry (Hologic 4500A), and to visceral fat area as measured by computerized tomography. We included 2,830 persons, 1,439 women and 1,391 men with complete data on all measurements. For both men and women, all measurements were strongly correlated with both total body fat and visceral fat except the waist/thigh ratio. However, waist circumference, sagittal diameter, weight, and body mass index were more closely related to total body fat than to visceral fat area (R2 for the linear regression of waist circumference on total body fat was 0.69 in women and men; R2 for linear regression of waist circumference on visceral fat area was 0.40 in women, and 0.49 in men). These data suggest that the contribution of visceral fat to health risks will be better assessed by directly measuring this fat depot.