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Research found that 37.65% of adults with diabetes had silent myocardial ischemia, with poor glycemic control, smoking, and long disease duration as key predictors.

A recent study published in Cureus revealed that over one-third of adults with diabetes harbored silent myocardial ischemia (SMI), with poor glycemic control, smoking, and diabetes duration exceeding 10 years emerging as key predictors.

“The current study revealed that 37.65% of asymptomatic individuals with diabetes had SMI, highlighting a significant hidden cardiovascular burden,” wrote study author Hafiz Abdul Manan, MBBS, London Northwest University Healthcare, and coauthors.

Despite its prognostic importance, SMI frequently remains undiagnosed in patients with diabetes due to a lack of symptom perception, particularly in those with autonomic neuropathy.

“Among the evaluated risk factors, poor glycemic control, as indicated by an HbA1c greater than 7%, was the strongest predictor of SMI (OR 3.21; 95% CI, 1.59–6.49; P=0.001), consistent with prior studies linking chronic hyperglycemia to endothelial dysfunction, oxidative stress, and accelerated atherosclerosis,” the authors reported.

Study Design & SMI Prevalence

The cross-sectional study included 162 outpatients with diabetes from Jinnah Hospital, Lahore. Participants were aged 40 years and older with a minimum diabetes duration of 5 years and no history of overt coronary artery disease. Each participant underwent a comprehensive evaluation including medical history, physical examination, laboratory testing, resting electrocardiogram (ECG), exercise stress testing, and myocardial perfusion imaging.

Researchers were primarily interested in two outcomes: the rate of undetected SMI in the cohort as well as independent predictors of SMI.

Independent Predictors of SMI

Multivariable logistic regression identified several independent predictors of SMI:

• Poor glycemic control: (HbA1c >7%) (OR: 3.21; 95% CI: 1.59-6.49; P=0.001)
• Smoking: (OR: 2.67; 95% CI: 1.32-5.41; P=0.006)
• Diabetes duration greater than 10 years: (OR: 2.34; 95% CI: 1.22-4.48; P=0.010)
• Dyslipidemia: (OR: 2.15; 95% CI: 1.18-3.93; P=0.012)
• Hypertension: (OR: 1.89; 95% CI: 1.02-3.51; P=0.041)
• Advancing age: OR 1.05 per year (95% CI, 1.01–1.09; P=0.003)

Notably, SMI prevalence increased sharply in patients older than 55 years.

A predictive model combining these factors achieved an area under the curve of 0.781, with 76.1% sensitivity and 70.3% specificity.

Recommendations

“We recommend repeated cardiovascular screening at regular intervals (eg, annually or biennially) for these high-risk individuals,” the researchers wrote, “as early detection of SMI through noninvasive diagnostic methods (such as stress ECG and myocardial perfusion imaging) can lead to timely interventions and significantly reduce the risk of unfavorable cardiac events.”