Table I.

Trials assessing or comparing revascularization methods (PCI or CABG) with each other or with medical treatment in patients with CHD, focusing on those with DM

Name of the study	Aim of the study	Number of patients	Type of study	Results
POLISH STEMI registry (10)	To investigate the impact of DM on mortality in STEMI patients treated with primary angioplasty	7,193 patients with ACS; 877 (12.2%) with DM	Registry analysis with prospectively collected data	Fewer primary PCI procedures with stenting (p<0.0001) and higher mortalityrate in patients with DM vs. patients without DM (adjusted HR=1.23; 95% CI 1.04-1.46, p=0.013) DM independently associated with impaired epicardial reperfusion (OR=1.33; 95% CI 1.07-1.64, p=0.009)
BARI (12–14)	CABG vs. PTCA in patients with multivessel CHD	1,829; 353 with DM	RCT	5-year survival rates higher in the CABG group (80.6% vs. 65.5%, p=0.003). Lower 5-year cardiac mortality rates (5.8% vs. 20.6%, p=0.0003) in DM patients. Similar 5-year survival rates in the 2 groups in patients without DM. Similar angina rates in the 2 groups, but higher revascularization rates in the PTCA group (76.8% vs. 20.3%, p<0.001) at 10-year follow-up. Higher survival rates in the CABG group (57.8% vs. 45.5%, p=0.025) at 10 years of DM
CABRI (15, 16)	PTCA vs. CABG in patients with symptomatic multivessel CHD	1,054; 125 (11.9%) with DM	RCT	PTCA group: higher mortality rates in diabetic vs. non-diabetic patients (22.6% vs. 9.4%, p=0.001) CABG group: similar mortality rates in diabetic and non-diabetic patients
Barsness et al. (18)	PTCA or CABG in patients with multivessel CHD	3,220; 24% with DM	Observational	Lower survival rates in patients with DM vs. those without (p<0.0001). No significant differential effect of diabetes on outcome between the PTCA and the CABG group
Carson et al. (19)	Patients undergoing CABG	146,786; 28.4% with DM	Cohort study	Higher 30-day mortality in diabetic vs. non-diabetic patients (3.7% vs. 2.7%; adjusted HR 1.23; 95% CI 1.15-1.32, p=0.002). Stroke, renal failure and infections more frequent in patients with DM
Portuguese Registry on ACS (24)	CABG (N=267) vs. PCI (N=3,948) or no PCI (N=8,773) in patients with ACS	12,988	Retrospective analysis of a nationwide database in Portugal	Very low in-hospital mortality (1.1%) in the CABG group
MASS II (26, 27)	Medical treatment vs. CABG vs. PCI in stable multivessel CHD patients	611, 190 with DM	RCT	Similar rates of cardiac death, STEMI and revascularization in PCI and medical therapy groups and lower rates in the CABG group
RITA I (28)	PTCA vs. CABG in patients with CHD	1,011	RCT	Trend toward lower mortality in the PTCA vs. the CABG group
RITA II (29)	PTCA vs. medical treatment in patients with CHD	1,018	RCT	Greater symptomatic improvement in the PTCA group
Steno-2 (31)	Intensified multifactorial intervention vs. conventional treatment in patients with DM and micro-albuminuria	160	Randomised, prospective, open, parallel trial	Lower risk of CVD (HR 0.47; 95% CI 0.24-0.73), nephropathy (HR 0.39; 95% CI 0.17-0.87), retinopathy (HR 0.42; 95% CI 0.21-0.86) and autonomic neuropathy (HR 0.37; 95% CI 0.18-0.79) with intensive treatment
BARI 2D (33, 34)	Insulin sensitization vs. insulin and intensive medical therapy with prompt coronary revascularization or at a later date in patients with DM and stable CHD	2,368	RCT	Similar 5-year cardiac mortality rates between revascularization plus intensive medical therapy and intensive medical therapy alone or between insulin sensitization and insulin provision. The MI (10.0% vs. 17.6%, p=0.003), all-cause death or MI (21.1% vs. 29.2%, p=0.01) and cardiac death or MI (p=0.03) less frequent in the revascularization plus intensive medical therapy vs. the intensive medical therapy group
Tarantini etal. (38)	PCI (using exclusively DES) vs. CABG in diabetic patients with multivessel CHD	220	Retrospective with prospectively collected data	Higher prevalence of 3-vessel disease (p<0.001), LAD involvement (p<0.001), presence of total occlusions (p=0.04) and collateral circulation (p<0.001) in the CABG group. No difference in MACCE between the 2 groups at 2-year follow-up
DESIRE (40)	PCI with DES	2,084 (28.9% with DM and 40.7% with ACS)	Prospective, non-randomized single-centre registry	0.7% STEMI and 1.6% in-stent thrombosis
Tamburino etal. (41)	Complete vs. incomplete revascularization with PCI using DES in patients with multivessel CHD	508	Retrospective with prospectively collected data	Lower HR for cardiac death, MI or repeat revascularization (0.43; 95% CI 0.29-0.63, p<0.0001), cardiac death (0.37; 95% CI 0.15-0.92, p=0.03), cardiac death or MI (0.34; 95% CI 0.16-0.75, p=0.008) and any repeat revascularization (0.45; 95% CI 0.29-0.69, p=0.0003) with complete revascularization
Qiao et al. (42)	CABG vs. DES-PCI in DM patients with multivessel CHD	645	Non-randomized	Similar total mortality in the 2 groups. Lower rate of major adverse CVD events in the CABG group (HR 0.15; 95% CI 0.06-0.37, p<0.001) mainly due to less repeat revascularization (HR 0.02, 95% CI 0.01-0.13, p<0.001)

ACS – acute coronary syndrome, BARI – Bypass Angioplasty Revascularization Investigation, BARI 2D – BARI 2 Diabetes, CABG – coronary artery bypass grafting, CABRI – Coronary Angioplasty versus Bypass Revascularization Investigation, CHD – coronary heart disease, CI – confidence interval, DES – drug-eluting stents, DESIRE – Drug-Eluting Stents in the Real World, DM – diabetes mellitus, EAST – Emory Angioplasty versus Surgery Trial, HR – hazard ratio, IMA – internal mammary artery, LAD – left anterior descending, MACCE – major adverse cardiac and cerebrovascular events, MASS – Medicine, Angioplasty or Surgery Study, MI – myocardial infarction, OR – odds ratio, PCI – percutaneous coronary intervention, PTCA – percutaneous transluminal coronary angioplasty, RCT – randomized control trial, RITA – Randomized Intervention Treatment of Angina, STEMI – ST-elevation myocardial infarction