Effects of fasting and/or postprandial glucose on heart rate recovery in patients with coronary heart disease

Determinants and prognostic value of cardiovascular autonomic function in coronary artery disease patients with and without type 2 diabetes

OBJECTIVE Cardiovascular autonomic dysfunction is a common finding among patients with coronary artery disease (CAD) and type 2 diabetes (T2D). The reasons and prognostic value of autonomic dysfunction in CAD patients with T2D are not well known. RESEARCH DESIGN AND METHODS We examined the association between heart rate recovery (HRR), 24-h heart rate (HR) variability (SD of normal R-R interval [SDNN]), and HR turbulence (HRT), and echocardiographic parameters, metabolic, inflammatory, and coronary risk variables, exercise capacity, and the presence of T2D among 1,060 patients with CAD (mean age 67 ± 8 years; 69% males; 50% patients with T2D). Second, we investigated how autonomic function predicts a composite end point of cardiovascular death, acute coronary event, stroke, and hospitalization for heart failure during a 2-year follow-up. RESULTS In multiple linear regression model, exercise capacity was a strong predictor of HRR (R = 0.34, P < 0.001), SDNN (R = 0.33, P < 0.001), and HRT (R = 0.13, P = 0.001). In univariate analyses, a composite end point was predicted by reduced HRR (hazard ratio 1.7 [95% CI 1.1-2.6]; P = 0.020), reduced SDNN (2.0 [95% CI 1.2-3.1]; P = 0.005), and blunted HRT (2.1 [1.3-3.4]; P = 0.003) only in patients with T2D. After multivariate adjustment, none of the autonomic markers predicted the end point, but high-sensitivity C-reactive protein (hs-CRP) remained an independent predictor. CONCLUSIONS Cardiovascular autonomic function in CAD patients is associated with several variables, including exercise capacity. Autonomic dysfunction predicts short-term cardiovascular events among CAD patients with T2D, but it is not as strong an independent predictor as hs-CRP.

Development of coronary heart disease and ischemic stroke in relation to fasting and 2-hour plasma glucose levels in the normal range

Background

Individuals who had normoglycemia but whose 2-hour plasma glucose (2hPG) concentrations did not return to the fasting plasma glucose (FPG) levels during an oral glucose tolerance test (OGTT) have been shown to have increased cardiovascular mortality. This is further investigated regarding to the first events of coronary heart disease (CHD) and ischemic stroke (IS).

Method

Data from 9 Finnish and Swedish cohorts comprising 3743 men and 3916 women aged 25 to 90 years who had FPG < 6.1 mmol/l and 2hPG < 7.8 mmol/l and free of CVD at enrolment were analyzed. Hazard ratios (HRs) for first CHD and IS events were estimated for the individuals with 2hPG > FPG (Group II) compared with those having 2hPG ≤ FPG (Group I).

Results

A total of 466 (115) CHD and 235 (106) IS events occurred in men (women) during a median follow-up of 16.4 years. Individuals in Group II were older and had greater body mass index, blood pressure, 2hPG and fasting insulin than those in Group I in both sexes. Multivariate adjusted HRs (95% confidence intervals) for incidence of CHD, IS, and composite CVD events (CHD + IS) in men were 1.13 (0.93-1.37), 1.40 (1.06-1.85) and 1.20 (1.01-1.42) in the Group II as compared with those in the Group I. The corresponding HRs in women were 1.33 (0.83-2.13), 0.94 (0.59-1.51) and 1.11 (0.79-1.54), respectively.

Conclusion

Within normoglycemic range individuals whose 2hPG did not return to their FPG levels during an OGTT had increased risk of CHD and IS.