Atypical presentation of acute and chronic coronary artery disease in diabetics

Table 1 Studies on silent myocardial ischemia as a mode of atypical presentation in diabetics

Ref.	Study population	Study type/country	Silent ischemia%	Conclusion
Arenja et al[36]	1621 pts in the derivation cohort + 338 pts in the validation cohort	Derivation cohort/ Switzerland	23.3%- 28.5% in DM and 21.5% in non-DM	DM is an independent predictor for the presence of SMI (OR = 1.5; 95%CI: 1.1-1.9, P = 0.004). In the validation cohort, the prevalence of SMI = 26.3% (n = 89), while the prevalencea in diabetics (35.8%) vs non-diabetics was 24% (P = 0.049)
Sheikh et al[37]	200 subjects, 31 diabetics vs 169 non-diabetics	A cross-sectional study/Pakistan	(19%) diabetics vs (13%) non-diabetics	No significant difference in the frequency of SMI in diabetics vs non-diabetics
Peña et al[38]	220 asymptomatic NIDDM patients	A prospective, observational, analytical study /Havana	29.10%	Type 2 diabetics with ischemia had ↑ levels of total cholesterol, LDL and triglycerides. HDL levels were significantly reducedb. The association of ↓ HDL with ↑ triglycerides was a strong indicator of SMI in NIDDM patients
Ruano Pérez et al[39]	56 asymptomatic diabetics	retrospective study	46.40%	Moderate-severe ischemia in 10.7%, necrosis with ischemia in 5.4% and necrosis in 7.1%, diabetic nephropathy was the only factor related to an abnormal SPECT (P = 0.043)
Blanchet Deverly et al[40]	147 NIDDM patients	cross-sectional study /France	23.10%	Multivariate logistic-regression analyses, the adjusted OR of SMI significantly ↑ in patients with a history of cardiovascular disease (4.36, 95%CI: 1.36-13.96, P = 0.01) and LVH (2.46, 95%CI: 1.03-5.86, P = 0.04)
Mbaye et al[41]	79 diabetics	Prospective/France	67.10%	Predominance of motion abnormalities in the anterior territory (83%). Cardiovascular risk factors associated with positivity of the test were microalbuminuria (P = 0.0001), inactivity (P = 0.0001), dyslipidemia (P = 0.0002), arterial hypertension (P = 0.001), smoking (0.003) and male sex (P = 0.004)
Bansal et al42]	1123 NIDDM patients	Prospective/Detection of Ischemia in Asymptomatic Diabetics ( DIAD) /United States and Canada (DIAD) study	21%-24% in the intermediate high risk group 19%-23% in the low risk group	Cardiac event ratesa in intermediate/high-risk. The annual cardiac event rate was ≤ 1% in all risk groups. In intermediate-/high-risk participants randomized to screening vs no screening, 4.8-yr cardiac event rates were similar (2.5%-4.8% vs 3.1%-3.7%)
Agarwal et al[43]	77 NIDDM	Prospective study/India	28.90%	The prevalence of SMI similar in males and females. Serum LDL levels > 140 mg % had a significant correlation with the prevalence of silent CAD (P = 0.04). The difference in CCA-IMT values was found to be statistically significant between the silent CAD and non-CAD groups (P = 0.019)
Ugur-Altun et al[44]	90 asymptomatic NIDDM patients	Prospective/Turkey	4%	Diabetics with SMI had ↑ fibrinogen level (372 ± 51 mg/dL vs 307 ± 71 mg/dL, P = 0.04), had b total exercise time and peak workload (375 ± 30 s vs 474 ± 115 s, P = 0.04; 7.3 ± 0.5 vs 8.9 ± 1.9, P = 0.04, respectively)
Chico et al[47]	353 NIDDM asymptomatic Caucasians	Prospective/Spain	8.50%	SMI patients were older, had ↑ prevalence of autonomic neuropathy, microalbuminuria, hypertension, and dyslipidemia than those without
Wackers et al[48]	1123 NIDDM patients	Prospective/United States	20%	Predictors for abnormal tests: abnormal Valsalva, male sex and diabetes duration (5.2). Traditional cardiac risk factors or inflammatory and prothrombotic markers were not predictive. Ischemic adenosine-induced ST-segment depression with normal perfusion in women
Falcone et al[50]	618 patients with CAD	Prospective/Italy	58%	SMI during exercise seen in 58% of diabetics and 64% of nondiabetics. Both diabetics and non-diabetics with exertional SMI had ↑ heart rate values (P < 0.01), SBP (P < 0.01), rate-pressure product (P < 0.001), work load (P < 0.01) and maximum ST depression at peak exercise (P < 0.05)
Coisne et al [51]	49 diabetics and 63 non-diabetics	Prospective/France	9%	Significant CAD detected in 9% of asymptomatic diabetics. Dynamic left ventricular obstruction observed in 59% of the diabetic population and in only 22% in the non-diabetic population
Sukhija et al[53]	30 diabetics/30 non diabetics	Prospective/India	46.70%	Diabetics had ↑ heart rate and a greater number of supraventricular and ventricular ectopics, aprevalence of multi-vessel involvement and diffuse disease compared to controls. 50% of diabetics and none of the controls had autonomic dysfunction. Autonomic dysfunction was present in 85.7% of diabetics with SMI vs 18.7% of diabetics without SMI (P = 0.001)
May et al[54]	240 diabetics	Prospective/Denmark	13.50%	Frequency of SMI did not differ significantly between diabetics and non-diabetics. Systolic blood pressure was predictive of SMI in diabetes
Tamez-Pérez et al[55]	60 NIDDM patients	Prospective/ Spain	17%	In a 2-yr follow-up, 4 diabetics developed symptomatic angina pectoris
Ahluwalia et al[56]	20 male diabetics	Prospective/India	50%	On exercise testing in diabetics, SMI was detected in 64% of the patients with 3 vessel disease, 50% of the patients with 2 vessel disease and 20% of the patients with one-vessel disease vs 18% of non-diabetic patients with three-vessel disease (P < 0.05) and in none of the patients with two- or one-vessel disease
Tanaka et al[61]	92 NIDDM patients	Prospective / Japan	38%	Diabetics with positive treadmill test were smokers, and had hypertension and ↑ triglyceride level compared to treadmill negative diabetics
Nesto et al[62]	30 diabetics with peripheral vascular disease	Prospective /United States	57%	57% had thallium abnormalities, with reversible thallium defects compatible with ischemia in 47% and evidence of prior, clinical SMI in 37%. Thallium abnormalities were seen more frequently in diabetics with concomitant hypertension and cigarette smoking (P = 0.001)
Koistinen et al[63]	136 diabetic subjects	Controlled study/ Finland	29%	Coronary angiography of 34 diabetics; 12 had significant coronary artery narrowing; seven had unimportant atherosclerosis; 15 had patent coronary arteries
Theron et al[64]	52 IDDM and 87 NIDDM subjects	Prospective /South Africa	See conclusion	No statistically significant relationship between any parameter and the presence of autonomic neuropathy. Atypical infarctions not limited to subjects with autonomic neuropathy, the incidence mucha than the general population
Touze et al[65]	50 black African diabetics	Prospective /Africa	10%	SMI was ↓ among black African diabetics compared with white diabetics. The coronary lesions were mostly limited. Proximal narrowing and one-vessel disease mostly encountered-

^aIncrease/higher;

^bDecreased/lower. CAD: Coronary artery disease; IDDM: Insulin dependent diabetes mellitus; NIDDM: Non-insulin dependent diabetes mellitus; MI: Myocardial infarction; HDL: High density lipoprotein; LDL: Low density lipoprotein; SMI: Silent myocardial ischemia/infarction; CCA-IMT: Common carotid artery intimal medial thickness