Elizabeth Selvin

Diabetes mellitus, fasting blood glucose concentration, and risk of vascular disease: a collaborative meta-analysis of 102 prospective studies

Summary Background Uncertainties persist about the magnitude of associations of diabetes mellitus and fasting glucose concentration with risk of coronary heart disease and major stroke subtypes. We aimed to quantify these associations for a wide range of circumstances. Methods We undertook a meta-analysis of individual records of diabetes, fasting blood glucose concentration, and other risk factors in people without initial vascular disease from studies in the Emerging Risk Factors Collaboration. We combined within-study regressions that were adjusted for age, sex, smoking, systolic blood pressure, and body-mass index to calculate hazard ratios (HRs) for vascular disease. Findings Analyses included data for 698 782 people (52 765 non-fatal or fatal vascular outcomes; 8·49 million person-years at risk) from 102 prospective studies. Adjusted HRs with diabetes were: 2·00 (95% CI 1·83–2·19) for coronary heart disease; 2·27 (1·95–2·65) for ischaemic stroke; 1·56 (1·19–2·05) for haemorrhagic stroke; 1·84 (1·59–2·13) for unclassified stroke; and 1·73 (1·51–1·98) for the aggregate of other vascular deaths. HRs did not change appreciably after further adjustment for lipid, inflammatory, or renal markers. HRs for coronary heart disease were higher in women than in men, at 40–59 years than at 70 years and older, and with fatal than with non-fatal disease. At an adult population-wide prevalence of 10%, diabetes was estimated to account for 11% (10–12%) of vascular deaths. Fasting blood glucose concentration was non-linearly related to vascular risk, with no significant associations between 3·90 mmol/L and 5·59 mmol/L. Compared with fasting blood glucose concentrations of 3·90–5·59 mmol/L, HRs for coronary heart disease were: 1·07 (0·97–1·18) for lower than 3·90 mmol/L; 1·11 (1·04–1·18) for 5·60–6·09 mmol/L; and 1·17 (1·08–1·26) for 6·10–6·99 mmol/L. In people without a history of diabetes, information about fasting blood glucose concentration or impaired fasting glucose status did not significantly improve metrics of vascular disease prediction when added to information about several conventional risk factors. Interpretation Diabetes confers about a two-fold excess risk for a wide range of vascular diseases, independently from other conventional risk factors. In people without diabetes, fasting blood glucose concentration is modestly and non-linearly associated with risk of vascular disease. Funding British Heart Foundation, UK Medical Research Council, and Pfizer.BACKGROUND Uncertainties persist about the magnitude of associations of diabetes mellitus and fasting glucose concentration with risk of coronary heart disease and major stroke subtypes. We aimed to quantify these associations for a wide range of circumstances. METHODS We undertook a meta-analysis of individual records of diabetes, fasting blood glucose concentration, and other risk factors in people without initial vascular disease from studies in the Emerging Risk Factors Collaboration. We combined within-study regressions that were adjusted for age, sex, smoking, systolic blood pressure, and body-mass index to calculate hazard ratios (HRs) for vascular disease. FINDINGS Analyses included data for 698 782 people (52 765 non-fatal or fatal vascular outcomes; 8.49 million person-years at risk) from 102 prospective studies. Adjusted HRs with diabetes were: 2.00 (95% CI 1.83-2.19) for coronary heart disease; 2.27 (1.95-2.65) for ischaemic stroke; 1.56 (1.19-2.05) for haemorrhagic stroke; 1.84 (1.59-2.13) for unclassified stroke; and 1.73 (1.51-1.98) for the aggregate of other vascular deaths. HRs did not change appreciably after further adjustment for lipid, inflammatory, or renal markers. HRs for coronary heart disease were higher in women than in men, at 40-59 years than at 70 years and older, and with fatal than with non-fatal disease. At an adult population-wide prevalence of 10%, diabetes was estimated to account for 11% (10-12%) of vascular deaths. Fasting blood glucose concentration was non-linearly related to vascular risk, with no significant associations between 3.90 mmol/L and 5.59 mmol/L. Compared with fasting blood glucose concentrations of 3.90-5.59 mmol/L, HRs for coronary heart disease were: 1.07 (0.97-1.18) for lower than 3.90 mmol/L; 1.11 (1.04-1.18) for 5.60-6.09 mmol/L; and 1.17 (1.08-1.26) for 6.10-6.99 mmol/L. In people without a history of diabetes, information about fasting blood glucose concentration or impaired fasting glucose status did not significantly improve metrics of vascular disease prediction when added to information about several conventional risk factors. INTERPRETATION Diabetes confers about a two-fold excess risk for a wide range of vascular diseases, independently from other conventional risk factors. In people without diabetes, fasting blood glucose concentration is modestly and non-linearly associated with risk of vascular disease. FUNDING British Heart Foundation, UK Medical Research Council, and Pfizer.

Prevalence of and Risk Factors for Peripheral Arterial Disease in the United States Results From the National Health and Nutrition Examination Survey, 1999–2000

Background—Peripheral arterial disease (PAD) is associated with significant morbidity and mortality and is an important marker of subclinical coronary heart disease. However, estimates of PAD prevalence in the general US population have varied widely. Methods and Results—We analyzed data from 2174 participants aged 40 years and older from the 1999–2000 National Health and Nutrition Examination Survey. PAD was defined as an ankle-brachial index <0.90 in either leg. The prevalence of PAD among adults aged 40 years and over in the United States was 4.3% (95% CI 3.1% to 5.5%), which corresponds to ≈5 million individuals (95% CI 4 to 7 million). Among those aged 70 years or over, the prevalence was 14.5% (95% CI 10.8% to 18.2%). In age- and gender-adjusted logistic regression analyses, black race/ethnicity (OR 2.83, 95% CI 1.48 to 5.42) current smoking (OR 4.46, 95% CI 2.25 to 8.84), diabetes (OR 2.71, 95% CI 1.03 to 7.12), hypertension (OR 1.75, 95% CI 0.97 to 3.13), hypercholesterolemia (OR 1.68, 95% CI 1.09 to 2.57), and low kidney function (OR 2.00, 95% CI 1.08 to 3.70) were positively associated with prevalent PAD. More than 95% of persons with PAD had 1 or more cardiovascular disease risk factors. Elevated fibrinogen and C-reactive protein levels were also associated with PAD. Conclusions—This study provides nationally representative prevalence estimates of PAD in the United States, revealing that PAD affects more than 5 million adults. PAD prevalence increases dramatically with age and disproportionately affects blacks. The vast majority of individuals with PAD have 1 or more cardiovascular disease risk factors that should be targeted for therapy.

Type 2 diabetes, glucose homeostasis and incident atrial fibrillation: the Atherosclerosis Risk in Communities study

Background Type 2 diabetes has been inconsistently associated with the risk of atrial fibrillation (AF) in previous studies that have frequently been beset by methodological challenges. Design Prospective cohort study. Setting The Atherosclerosis Risk in Communities (ARIC) study. Participants Detailed medical histories were obtained from 13 025 participants. Individuals were categorised as having no diabetes, pre-diabetes or diabetes based on the 2010 American Diabetes Association criteria at study baseline (1990–2). Main outcome measures Diagnoses of incident AF were obtained to the end of 2007. Associations between type 2 diabetes and markers of glucose homeostasis and the incidence of AF were estimated using Cox proportional hazards models after adjusting for possible confounders. Results Type 2 diabetes was associated with a significant increase in the risk of AF (HR 1.35, 95% CI 1.14 to 1.60) after adjustment for confounders. There was no indication that individuals with pre-diabetes or those with undiagnosed diabetes were at increased risk of AF compared with those without diabetes. A positive linear association was observed between HbA1c and the risk of AF in those with and without diabetes (HR 1.13, 95% CI 1.07 to 1.20) and HR 1.05, 95% CI 0.96 to 1.15 per 1% point increase, respectively). There was no association between fasting glucose or insulin in those without diabetes, but a significant association with fasting glucose was found in those with the condition. The results were similar in white subjects and African-Americans. Conclusions Diabetes, HbA1c level and poor glycaemic control are independently associated with an increased risk of AF, but the underlying mechanisms governing the relationship are unknown and warrant further investigation.

Diabetes Mellitus, Fasting Glucose, and Risk of Cause-Specific Death

BACKGROUND The extent to which diabetes mellitus or hyperglycemia is related to risk of death from cancer or other nonvascular conditions is uncertain. METHODS We calculated hazard ratios for cause-specific death, according to baseline diabetes status or fasting glucose level, from individual-participant data on 123,205 deaths among 820,900 people in 97 prospective studies. RESULTS After adjustment for age, sex, smoking status, and body-mass index, hazard ratios among persons with diabetes as compared with persons without diabetes were as follows: 1.80 (95% confidence interval [CI], 1.71 to 1.90) for death from any cause, 1.25 (95% CI, 1.19 to 1.31) for death from cancer, 2.32 (95% CI, 2.11 to 2.56) for death from vascular causes, and 1.73 (95% CI, 1.62 to 1.85) for death from other causes. Diabetes (vs. no diabetes) was moderately associated with death from cancers of the liver, pancreas, ovary, colorectum, lung, bladder, and breast. Aside from cancer and vascular disease, diabetes (vs. no diabetes) was also associated with death from renal disease, liver disease, pneumonia and other infectious diseases, mental disorders, nonhepatic digestive diseases, external causes, intentional self-harm, nervous-system disorders, and chronic obstructive pulmonary disease. Hazard ratios were appreciably reduced after further adjustment for glycemia measures, but not after adjustment for systolic blood pressure, lipid levels, inflammation or renal markers. Fasting glucose levels exceeding 100 mg per deciliter (5.6 mmol per liter), but not levels of 70 to 100 mg per deciliter (3.9 to 5.6 mmol per liter), were associated with death. A 50-year-old with diabetes died, on average, 6 years earlier than a counterpart without diabetes, with about 40% of the difference in survival attributable to excess nonvascular deaths. CONCLUSIONS In addition to vascular disease, diabetes is associated with substantial premature death from several cancers, infectious diseases, external causes, intentional self-harm, and degenerative disorders, independent of several major risk factors. (Funded by the British Heart Foundation and others.).

Systematic Review: Comparative Effectiveness and Safety of Oral Medications for Type 2 Diabetes Mellitus

The prevalence and morbidity associated with type 2 diabetes mellitus continue to increase in the United States and elsewhere (1, 2). Several studies of the treatment of type 2 diabetes suggest that improved glycemic control reduces microvascular risks (37). In contrast, the effects of treatment on macrovascular risk are more controversial (3, 4, 8, 9), and the comparative effects of oral diabetes agents on clinical outcomes are even less certain. As newer oral agents, such as thiazolidinediones and meglitinides, are increasingly marketed, clinicians and patients must decide whether they prefer these generally more costly medications over older agents, such as sulfonylureas and metformin. Systematic reviews and meta-analyses of oral diabetes agents have attempted to fill this gap (1019), but few have compared all agents with one another (18, 19). The few investigations that have compared all oral agents focused narrowly on individual outcomes, such as hemoglobin A1c level (18) or serum lipid levels (19). No systematic review has summarized all available head-to-head comparisons with regard to the full range of intermediate end points (including hemoglobin A1c level, lipid levels, and body weight) and other clinically important outcomes, such as adverse effects and macrovascular risks. Therefore, the Agency for Healthcare Research and Quality commissioned a systematic review to summarize the comparative benefits and harms of oral agents that are used to treat type 2 diabetes. Methods Data Sources and Selection We searched MEDLINE, EMBASE, and the Cochrane Central Register of Controlled Trials from inception to January 2006 for original articles. We also searched these databases until November 2005 for systematic reviews. We reviewed reference lists of related reviews and original data articles, hand-searched recent issues of 15 medical journals, invited experts to provide additional citations, reviewed selected medications from the U.S. Food and Drug Administration (FDA) Web site, and reviewed unpublished data from several pharmaceutical companies and public registries of clinical trials. Our search strategy for the bibliographic databases combined terms for type 2 diabetes and oral diabetes agents and was limited to English-language articles and studies in adults. The search for systematic reviews was similar but included terms for study design as well. We selected studies that included original data on adults with type 2 diabetes and assessed benefits or harms of FDA-approved oral diabetes agents that were available in the United States as of January 2006. To facilitate head-to-head comparisons of drug classes, we included drugs not on the U.S. market if members of their class were in use and had not been banned (voglibose, gliclazide, and glibenclamide). We also included studies of combinations of therapies that are commonly used, such as combinations of metformin, second-generation sulfonylureas, and thiazolidinediones. We excluded studies that evaluated combinations of 3 oral diabetes agents, and we also excluded first-generation sulfonylureas, because few clinicians prescribe these medications. We sought studies that reported on major clinical outcomes (for example, all-cause mortality, cardiovascular morbidity and mortality, and microvascular outcomes) or any of the following intermediate end points or adverse events: hemoglobin A1c level, body weight, systolic and diastolic blood pressure, high-density lipoprotein (HDL) cholesterol level, low-density lipoprotein (LDL) cholesterol level, triglyceride level, hypoglycemia, gastrointestinal problems, congestive heart failure, edema or hypervolemia, lactic acidosis, elevated aminotransferase levels, liver failure, anemia, leukopenia, thrombocytopenia, allergic reactions requiring hospitalization or causing death, and other serious adverse events. For intermediate end points, we included only randomized, controlled trials, which were abundant. For major clinical end points and adverse events, we considered observational studies as well as trials, because fewer randomized trials assessed these end points. We excluded studies that followed patients for less than 3 months (the conventional threshold for determining effects on hemoglobin A1c) or had fewer than 40 patients. Figure 1 shows the search and selection process, and the full technical report (available at effectivehealthcare.ahrq.gov/repFiles/OralFullReport.pdf) provides a more detailed description of the study methods (20). Figure 1. Study flow diagram. Data Extraction and Quality Assessment One investigator used standardized forms to abstract data about study samples, interventions, designs, and outcomes, and a second investigator confirmed the abstracted data. Two investigators independently applied the Jadad scale to assess some aspects of the quality of randomized trials (21). We considered observational studies and nonrandomized trials to provide weaker evidence than randomized trials, and we did not use a standardized scoring system to assess their quality (22). We used the GRADE (Grading of Recommendations Assessment, Development and Evaluation) working group definitions to grade the overall strength of the evidence as high, moderate, low, very low, or insufficient (23). Data Synthesis and Analysis We first performed a qualitative synthesis based on scientific rigor and type of end point. In general, we described the UKPDS (United Kingdom Prospective Diabetes Study) separately, because this large randomized, controlled trial differed from other trials in design, end points, and duration. When data were sufficient (that is, obtained from at least 2 randomized, controlled trials) and studies were relatively homogeneous in sample characteristics, study duration, and drug dose, we conducted meta-analyses for the following intermediate outcomes and adverse effects: hemoglobin A1c level, weight, systolic blood pressure, LDL cholesterol level, HDL cholesterol level, triglyceride level, and hypoglycemia. For trials with more than 1 dosing group, we chose the dose that was most comparable with other trials and most clinically relevant. We combined drugs into drug classes only when similar results were found across individual drugs. We could not perform formal meta-analyses for microvascular or macrovascular outcomes, mortality, and adverse events other than hypoglycemia because of methodological diversity among the trials or insufficient numbers of trials. We used a random-effects model with the DerSimonian and Laird formula to derive pooled estimates (posttreatment weighted mean differences for intermediate outcomes and posttreatment absolute risk differences for adverse events) (24). We tested for heterogeneity among the trials by using a chi-square test with set to 0.10 or less and an I 2 statistic greater than 50% (25). If heterogeneity was found, we conducted meta-regression analyses by using study-level characteristics of double-blinding, study duration, and dose ratio (calculated as the dose given in the study divided by the maximum approved dose of drug). The full report contains data on indirect comparisons, in which 2 interventions are compared through their relative effect against a common comparator (20). We tested for publication bias by using the tests of Begg and Mazumdar (26) and Egger and colleagues (27). All statistical analyses were done by using STATA Intercooled, version 8.0 (Stata, College Station, Texas). Role of the Funding Source The Agency for Healthcare Research and Quality suggested the initial questions and provided copyright release for this manuscript but did not participate in the literature search, data analysis, or interpretation of the results. Results Comparative Effectiveness of Oral Diabetes Agents in Reducing the Risk for Microvascular and Macrovascular Outcomes and Death We found no definitive evidence about the comparative effectiveness of oral diabetes agents on all-cause mortality, cardiovascular mortality or morbidity, peripheral arterial disease, neuropathy, retinopathy, or nephropathy (Table 1). For each head-to-head comparison on specific outcomes, the number of randomized trials (3 trials) and the absolute number of events were small (20). The few observational studies were limited in quantity, consistency, and adjustment for key confounders. Table 1. Evidence of the Comparative Effectiveness of Oral Diabetes Medications on Mortality, Microvascular and Macrovascular Outcomes, and Intermediate End Points Since our review, 2 high-profile comparative randomized trials with about 4 years of follow-up have been published, providing data on cardiovascular outcomes (28, 29). In ADOPT (A Diabetes Outcome Progression Trial) (28), the incidence of cardiovascular events was lower with glyburide than with rosiglitazone or metformin (1.8%, 3.4%, and 3.2%, respectively; P< 0.05). This effect was mainly driven by fewer congestive heart failure events and a lower rate of nonfatal myocardial infarction events in the glyburide group. Loss to follow-up was high (40%) and was disproportionate among the groups and therefore may account for some differences among groups. The interim analysis of the RECORD (Rosiglitazone Evaluated for Cardiac Outcomes and Regulation of Glycaemia in Diabetes) study reported that rosiglitazone plus metformin or a sulfonylurea compared with metformin plus a sulfonylurea had a hazard ratio of 1.08 (95% CI, 0.89 to 1.31) for the primary end point of hospitalization or death from cardiovascular disease (29). The hazard ratio was driven by more congestive heart failure in the rosiglitazone plus metformin or sulfonylurea group than in the control group of metformin plus sulfonylurea (absolute risk, 1.7% vs. 0.8%, respectively). In KaplanMeier curves, the risk for hospitalization or death from myocardial infarction was slightly lower in the control group than in the rosiglitazone group, but the difference was not statistically significant. A limitation of

Lead, Cadmium, Smoking, and Increased Risk of Peripheral Arterial Disease

Background— Lead and cadmium exposure may promote atherosclerosis, although the cardiovascular effects of chronic low-dose exposure are largely unknown. The objective of the present study was to evaluate the association between blood levels of lead and cadmium and peripheral arterial disease. Methods and Results— We analyzed data from 2125 participants who were ≥ 40 years of age in the 1999 to 2000 National Health and Nutrition Examination Survey (NHANES). Peripheral arterial disease was defined as an ankle brachial index <0.9 in at least 1 leg. Lead and cadmium levels were measured by atomic absorption spectrometry. After adjustment for demographic and cardiovascular risk factors, the ORs of peripheral arterial disease comparing quartiles 2 to 4 of lead with the lowest quartile were 1.63 (95% CI, 0.51 to 5.15), 1.92 (95% CI, 0.62 to 9.47), and 2.88 (95% CI, 0.87 to 9.47), respectively (P for trend=0.02). The corresponding ORs for cadmium were 1.07 (95% CI, 0.44 to 2.60), 1.30 (95% CI, 0.69 to 2.44), and 2.82 (95% CI, 1.36 to 5.85), respectively (P for trend=0.01). The OR of peripheral arterial disease for current smokers compared with never smokers was 4.13. Adjustment for lead reduced this OR to 3.38, and adjustment for cadmium reduced it to 1.84. Conclusions— Blood lead and cadmium, at levels well below current safety standards, were associated with an increased prevalence of peripheral arterial disease in the general US population. Cadmium may partially mediate the effect of smoking on peripheral arterial disease.

Breast and Cervical Cancer Screening: Sociodemographic Predictors Among White, Black, and Hispanic Women

OBJECTIVES We evaluated the relationship between breast and cervical cancer screening and a variety of variables across race/ethnicity groups. METHODS Using logistic regression models, we analyzed data from the 1998 National Health Interview Survey to assess the relative importance of the independent variables in predicting use of cancer screening services. RESULTS Having a usual source of care was the most important predictor of cancer screening use for all race/ethnicity groups. Health insurance was associated with an increased likelihood of cancer screening. Smoking was associated with a decreased likelihood of cancer screening. CONCLUSIONS Regardless of race/ethnicity, most women follow mammography and cervical cancer screening guidelines. The identification of specific factors associated with adherence to cancer screening guidelines may help inform screening campaigns.

Androgens and Diabetes in Men: Results from the Third National Health and Nutrition Examination Survey (NHANES III)

OBJECTIVE—Low levels of androgens in men may play a role in the development of diabetes; however, few studies have examined the association between androgen concentration and diabetes in men in the general population. The objective of this study is to test the hypothesis that low normal levels of total, free, and bioavailable testosterone are associated with prevalent diabetes in men. RESEARCH DESIGN AND METHODS—The study sample included 1,413 adult men aged ≥20 years who participated in the morning session of the first phase of the Third National Health and Nutrition Examination Survey, a cross-sectional survey of the civilian, noninstitutionalized population of the U.S. Bioavailable and free testosterone levels were calculated from serum total testosterone, sex hormone–binding globulin, and albumin concentrations. RESULTS—In multivariable models adjusted for age, race/ethnicity, and adiposity, men in the first tertile (lowest) of free testosterone level were four times more likely to have prevalent diabetes compared with men in the third tertile (odds ratio 4.12 [95% CI 1.25–13.55]). Similarly, men in the first tertile of bioavailable testosterone also were approximately four times as likely to have prevalent diabetes compared wth men in the third tertile (3.93 [1.39–11.13]). These associations persisted even after excluding men with clinically abnormal testosterone concentrations defined as total testosterone <3.25 ng/ml or free testosterone <0.07 ng/ml. No clear association was observed for total testosterone after multivariable adjustment (P for trend across tertiles = 0.27). CONCLUSIONS—Low free and bioavailable testosterone concentrations in the normal range were associated with diabetes, independent of adiposity. These data suggest that low androgen levels may be a risk factor for diabetes in men.

Cardiovascular Outcomes in Trials of Oral Diabetes Medications: A Systematic Review

BACKGROUND A wide variety of oral diabetes medications are currently available for the treatment of type 2 diabetes mellitus, but it is unclear how these agents compare with respect to long-term cardiovascular risk. Our objective was to systematically examine the peer-reviewed literature on the cardiovascular risk associated with oral agents (second-generation sulfonylureas, biguanides, thiazolidinediones, and meglitinides) for treating adults with type 2 diabetes. METHODS We searched MEDLINE, EMBASE, and the Cochrane Central Register of Controlled Trials, from inception through January 19, 2006. Forty publications of controlled trials that reported information on cardiovascular events (primarily myocardial infarction and stroke) met our inclusion criteria. Using standardized protocols, 2 reviewers serially abstracted data from each article. Trials were first described qualitatively. For comparisons with 4 or more independent trials, results were pooled quantitatively using the Mantel-Haenszel method. Results are presented as odds ratios (ORs) and corresponding 95% confidence intervals (CIs). RESULTS Treatment with metformin hydrochloride was associated with a decreased risk of cardiovascular mortality (pooled OR, 0.74; 95% CI, 0.62-0.89) compared with any other oral diabetes agent or placebo; the results for cardiovascular morbidity and all-cause mortality were similar but not statistically significant. No other significant associations of oral diabetes agents with fatal or nonfatal cardiovascular disease or all-cause mortality were observed. When compared with any other agent or placebo, rosiglitazone was the only diabetes agent associated with an increased risk of cardiovascular morbidity or mortality, but this result was not statistically significant (OR, 1.68; 95% CI, 0.92-3.06). CONCLUSIONS Meta-analysis suggested that, compared with other oral diabetes agents and placebo, metformin was moderately protective and rosiglitazone possibly harmful, but lack of power prohibited firmer conclusions. Larger, long-term studies taken to hard end points and better reporting of cardiovascular events in short-term studies will be required to draw firm conclusions about major clinical benefits and risks related to oral diabetes agents.

Risk implications of the new CKD Epidemiology Collaboration (CKD-EPI) equation compared with the MDRD Study equation for estimated GFR: the Atherosclerosis Risk in Communities (ARIC) Study.

BACKGROUND The Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI) recently published an equation for estimated glomerular filtration rate (eGFR) using the same variables (serum creatinine level, age, sex, and race) as the Modification of Diet in Renal Disease (MDRD) Study equation. Although the CKD-EPI equation estimates GFR more precisely compared with the MDRD Study equation, whether this equation improves risk prediction is unknown. STUDY DESIGN Prospective cohort study, the Atherosclerosis Risk in Communities (ARIC) Study. SETTING & PARTICIPANTS 13,905 middle-aged participants without a history of cardiovascular disease with median follow-up of 16.9 years. PREDICTOR eGFR. OUTCOMES & MEASUREMENTS We compared the association of eGFR in categories (>or=120, 90-119, 60-89, 30-59, and <30 mL/min/1.73 m(2)) using the CKD-EPI and MDRD Study equations with risk of incident end-stage renal disease, all-cause mortality, coronary heart disease, and stroke. RESULTS The median value for eGFR(CKD-EPI) was higher than that for eGFR(MDRD) (97.6 vs 88.8 mL/min/1.73 m(2); P < 0.001). The CKD-EPI equation reclassified 44.9% (n = 3,079) and 43.5% (n = 151) of participants with eGFR(MDRD) of 60-89 and 30-59 mL/min/1.73 m(2), respectively, upward to a higher eGFR category, but reclassified no one with eGFR(MDRD) of 90-119 or <30 mL/min/1.73 m(2), decreasing the prevalence of CKD stages 3-5 from 2.7% to 1.6%. Participants with eGFR(MDRD) of 30-59 mL/min/1.73 m(2) who were reclassified upward had lower risk compared with those who were not reclassified (end-stage renal disease incidence rate ratio, 0.10 [95% CI, 0.03-0.33]; all-cause mortality, 0.30 [95% CI, 0.19-0.48]; coronary heart disease, 0.36 [95% CI, 0.21-0.61]; and stroke, 0.50 [95% CI, 0.24-1.02]). Similar results were observed for participants with eGFR(MDRD) of 60-89 mL/min/1.73 m(2). More frequent reclassification of younger, female, and white participants explained some of these trends. Net reclassification improvement in participants with eGFR < 120 mL/min/1.73 m(2) was positive for all outcomes (P < 0.001). LIMITATIONS Limited number of cases with eGFR < 60 mL/min/1.73 m(2) and no measurement of albuminuria. CONCLUSIONS The CKD-EPI equation more appropriately categorized individuals with respect to long-term clinical risk compared with the MDRD Study equation, suggesting improved clinical usefulness in this middle-aged population.