Determinants of successful glycemic control among participants in the BARI 2D trial: a post-hoc analysis.

OBJECTIVE: The BARI 2D trial compared insulin provision (IP) versus insulin sensitization (IS) for the primary outcome of total mortality in participants with T2DM and cardiovascular disease (CVD). In this analysis we examine baseline characteristics that are associated with successful long-term glycemic control. RESEARCH DESIGN AND METHODS: In a 2×2 factorial design, 2368 participants were randomized to either IP or IS therapy, and to either prompt revascularization with medical therapy or medical therapy alone. Successful long-term glycemic control (success) was defined by simultaneously meeting 1) a mean HbA1c level of <7.0% after each participant's third year of follow-up period, and 2) adherence with medications only from the assigned glycemic treatment arm during >80% of the BARI 2D follow-up. The association between baseline variables and success was determined using unadjusted and adjusted logistic regression models. RESULTS: 1917 participants (962 IP and 955 IS participants) had sufficiently long follow-up and data for this analysis. Among these IP and IS participants, 235 and 335 participants met both criteria of success, respectively (p<0.001). Those not on insulin at entry had higher odds of success (OR 2.25; CI 1.79-2.82) when treated with IS versus IP medications, irrespective of baseline HbA1c levels. Younger age, shorter duration of T2DM, and lower HbA1c at baseline were also each independently associated with higher success when treated with IS versus IP medications. CONCLUSION: Patients similar to those in the BARI 2D trial may have a higher chance of achieving success with IS versus IP medications if they are younger, have shorter duration of T2DM, have lower HbA1c levels, have moderate or strenuous physically activity, and are not on insulin. In contrast, increasing age, longer duration of T2DM, higher HbA1c, and insulin therapy are associated with increased chance of success if treated with IP medications.

Favorable effects of insulin sensitizers pertinent to peripheral arterial disease in type 2 diabetes: results from the Bypass Angioplasty Revascularization Investigation 2 Diabetes (BARI 2D) trial.

OBJECTIVE: The aim of this manuscript was to report the risk of incident peripheral arterial disease (PAD) in a large randomized clinical trial that enrolled participants with stable coronary artery disease and type 2 diabetes and compare the risk between assigned treatment arms. RESEARCH DESIGN AND METHODS: The Bypass Angioplasty Revascularization Investigation 2 Diabetes (BARI 2D) trial randomly assigned participants to insulin sensitization (IS) therapy versus insulin-providing (IP) therapy for glycemic control. Results showed similar 5-year mortality in the two glycemic treatment arms. In secondary analyses reported here, we examine the effects of treatment assignment on the incidence of PAD. A total of 1,479 BARI 2D participants with normal ankle-brachial index (ABI) (0.91-1.30) were eligible for analysis. The following PAD-related outcomes are evaluated in this article: new low ABI≤0.9, a lower-extremity revascularization, lower-extremity amputation, and a composite of the three outcomes. RESULTS: During an average 4.6 years of follow-up, 303 participants experienced one or more of the outcomes listed above. Incidence of the composite outcome was significantly lower among participants assigned to IS therapy than those assigned to IP therapy (16.9 vs. 24.1%; P<0.001). The difference was significant in time-to-event analysis (hazard ratio 0.66 [95% CI 0.51-0.83], P<0.001) and remained significant after adjustment for in-trial HbA1c (0.76 [0.59-0.96], P=0.02). CONCLUSIONS: In participants with type 2 diabetes who are free from PAD, a glycemic control strategy of insulin sensitization may be the preferred therapeutic strategy to reduce the incidence of PAD and subsequent outcomes.

Ankle-brachial index and cardiovascular outcomes in the Bypass Angioplasty Revascularization Investigation 2 Diabetes trial.

BACKGROUND: Peripheral arterial disease increases cardiovascular risk in many patient populations. The risks associated with an abnormal ankle-brachial index (ABI) in patients with type 2 diabetes and stable coronary artery disease have not been well described with respect to thresholds and types of cardiovascular events. METHODS: We examined 2,368 patients in the BARI 2D trial who underwent ABI assessment at baseline. Death and major cardiovascular events (death, myocardial infarction and stroke) during follow-up (average 4.3 years) were assessed across the ABI spectrum and by categorized ABI: low (≤0.90), normal (0.91-1.3), high (>1.3), or noncompressible. RESULTS: A total of 12,568 person-years were available for mortality analysis. During follow-up, 316 patients died, and 549 had major cardiovascular events. After adjustment for potential confounders, with normal ABI as the referent group, a low ABI conferred an increased risk of death (relative risk [RR] 1.6, CI 1.2-2.2, P = .0005) and major cardiovascular events (RR 1.4, CI 1.1-1.7, P = .004). Patients with a high ABI had similar outcomes as patients with a normal ABI, but risk again increased in patients with a noncompressible ABI with a risk of death (RR 1.9, CI 1.3-2.8, P = .001) and major cardiovascular event (RR 1.5, CI 1.1-2.1, P = .01). CONCLUSIONS: In patients with coronary artery disease and type 2 diabetes, ABI screening and identification of ABI abnormalities including a low ABI (<1.0) or noncompressible artery provide incremental prognostic information.

The prevalence and predictors of an abnormal ankle-brachial index in the Bypass Angioplasty Revascularization Investigation 2 Diabetes (BARI 2D) trial.

OBJECTIVE: To examine ankle-brachial index (ABI) abnormalities in patients with type 2 diabetes and coronary artery disease (CAD). RESEARCH DESIGN AND METHODS: An ABI was obtained in 2,240 patients in the Bypass Angioplasty Revascularization Investigation 2 Diabetes (BARI 2D) Trial. ABIs were classified as: normal, 0.91-1.3; low, ≤ 0.9; high, >1.3; or noncompressible artery (NC). Baseline characteristics were examined according to ABI and by multivariate analysis. RESULTS ABI was normal in 66%, low in 19%, and high in 8% of patients, and 6% of patients had NC. Of the low ABI patients, 68% were asymptomatic. Using normal ABI as referent, low ABI was independently associated with smoking, female sex, black race, hypertension, age, C-reactive protein, diabetes duration, and lower BMI. High ABI was associated with male sex, nonblack race, and higher BMI; and NC artery was associated with diabetes duration, higher BMI, and hypertension. CONCLUSIONS: ABI abnormalities are common and often asymptomatic in patients with type 2 diabetes and CAD.

Association between albuminuria and duration of diabetes and myocardial dysfunction and peripheral arterial disease among patients with stable coronary artery disease in the BARI 2D study.

OBJECTIVE: To evaluate the effect of prior duration of diabetes, glycated hemoglobin level at study entry, and microalbuminuria or macroalbuminuria on the extent and severity of coronary artery disease (CAD) and peripheral arterial disease. PATIENTS AND METHODS: We studied baseline characteristics of the 2368 participants of the BARI 2D (Bypass Angioplasty Revascularization Investigation 2 Diabetes) study, a randomized clinical trial that evaluates treatment efficacy for patients with type 2 diabetes and angiographically documented stable CAD. Patients were enrolled from January 1, 2001, through March 31, 2005. Peripheral arterial disease was ascertained by an ankle-brachial index (ABI) of 0.9 or less, and extent of CAD was measured by presence of multivessel disease, a left ventricular ejection fraction (LVEF) of less than 50%, and myocardial jeopardy index. RESULTS: Duration of diabetes of 20 or more years was associated with increased risk of ABI of 0.9 or less (odds ratio [OR], 1.54; 95% confidence interval [CI], 1.04-2.26), intermittent claudication (OR, 1.61; 95% CI, 1.10-2.35), and LVEF of less than 50% (OR, 2.03; 95% CI, 1.37-3.02). Microalbuminuria was associated with intermittent claudication (OR, 1.53; 95% CI, 1.16-2.02) and ABI of 0.9 or less (OR, 1.31; 95% CI, 0.98-1.75), whereas macroalbuminuria was associated with abnormal ABI, claudication, and LVEF of less than 50%. There was a significant association between diabetes duration and extent of CAD as manifested by number of coronary lesions, but no other significant associations were observed between duration of disease, glycated hemoglobin levels, or albumin-to-creatinine ratio and other manifestations of CAD. CONCLUSION: Duration of diabetes and microalbuminuria or macroalbuminuria are important predictors of severity of peripheral arterial disease and left ventricular dysfunction in a cohort of patients selected for the presence of CAD.