Impact of diabetes on long-term mortality after presentation with acute myocardial infarction

Long-term mortality after acute myocardial infarction among individuals with and without diabetes: A systematic review and meta-analysis of studies in the post-reperfusion era

AIMS

To conduct a systematic review and meta-analysis with the aim of providing robust estimates of the association between diabetes and long-term (≥1 year) mortality after acute myocardial infarction (AMI).

MATERIAL AND METHODS

Medline, Embase and Web of Science databases were searched (January 1985 to July 2016) for terms related to long-term mortality, diabetes and AMI. Two authors independently abstracted the data. Hazard ratios (HRs) comparing mortality in people with and without diabetes were pooled across studies using Bayesian random-effects meta-analysis.

RESULTS

A total of 10 randomized controlled trials and 56 cohort studies, including 714 780 patients, reported an estimated total of 202 411 deaths over the median (range) follow-up of 2.0 (1-20) years. The risk of death over time was significantly higher among those with diabetes compared with those without (unadjusted HR 1.82, 95% credible interval [CrI] 1.73-1.91). Mortality remained higher in the analysis restricted to 23/64 cohorts reporting data adjusted for confounders (adjusted HR 1.48, 95% CrI 1.43-1.53). The excess long-term mortality in diabetes was evident irrespective of the phenotype and modern treatment of AMI, and persisted in early survivors (unadjusted HR 1.82, 95% CrI 1.70-1.95).

CONCLUSIONS

Despite medical advances, individuals with diabetes have a 50% greater long-term mortality compared with those without. Further research to understand the determinants of this excess risk are important for public health, given the predicted rise in global diabetes prevalence.

Cardiovascular risk in pulmonary alveolar proteinosis

We hypothesized that cardiovascular events and/or indices of cardiac dysfunction may be increased in pulmonary alveolar proteinosis (PAP). Systemic and pulmonary arterial hypertension, arrhythmias, pulmonary embolism, stroke and ischemic heart attack were reported. Patients underwent serum anti-GM-CSF antibodies, disease severity score (DSS), Doppler transthoracic echocardiograph, glucose, thyroid hormones, lipids, troponin and pro-Brain natriuretic peptide (BNP) examination. Thirteen patients (8 female) were studied, median age of 47. Pro-BNP inversely related to DLCO% and TLC%; troponin directly related to DSS, age, P(A-a)O2, left atrium-, left ventricle-end-diastole diameter and BMI. On multiple regression analysis DSS was the only parameter significantly and strongly related with troponin (R(2) = 0.776, p = 0.007). No cardiovascular event was reported during follow-up. In PAP cardiovascular risk indices relate to lung disease severity. Therefore, PAP patients could be at increased risk for cardiovascular events. Quantitation of its magnitude and potential links to lungs' physiologic derangement will be addressed in future studies.

Coronary plaque quantification and composition in asymptomatic patients with type II diabetes mellitus

OBJECTIVE

The aim of this study was to characterize the extent and morphology of coronary lesions in asymptomatic patients with type II diabetes mellitus.

METHODS

We enrolled 102 asymptomatic patients with type II diabetes mellitus and 97 patients without diabetes as controls. All individuals had no history of ischemic heart disease. They underwent multidetector computed tomography (MDCT). Plaque density and plaque volume were calculated using specific software on axial images. Arterial remodeling was evaluated with semiquantitative assessment on image reconstructions.

RESULTS

MDCT angiography revealed the presence of 124 coronary plaques in 46 patients with type II diabetes mellitus and 59 plaques in 21 controls (P<0.01). Diabetic patients had a significantly higher proportion of lesions with impaired adaptive remodeling (56.5 versus 35.6%, P<0.01), as compared with nondiabetic individuals. The volume of fibrofatty component was 0.1 cm (0.01-0.72) in diabetic patients and 0.08 cm (0.01-0.33) in controls (P=0.14). The calcium volume was 0.082 cm (0-0.558) in diabetic patients and 0.12 cm (0-0.669) in controls (P=0.21). Plaques with fibrofatty components had a significantly higher density in the diabetic cohort (58.76  ±  9.55  Hounsfield Units), as compared with the control group (47.31  ±  5.42 Hounsfield Units, P<0.001). Plaque density correlated with the duration of type II diabetes mellitus (r=0.37, P=0.044), but was independent of age, sex, hypertension and metabolic profile. In the control group, plaque density was independent of any covariate.

CONCLUSION

Coronary plaques in type II diabetes mellitus show a tendency to develop impaired adaptive remodeling and to have a higher tissue density.