What is the odds ratio of a myocardial infarction in individuals with hypertension compared to those without hypertension?

Odds Ratio of Myocardial Infarction in Individuals with Hypertension

Individuals with hypertension have approximately 5.4 to 9.5 times higher odds of experiencing a myocardial infarction compared to those without hypertension. 1

Evidence Overview

The relationship between hypertension and myocardial infarction (MI) is well-established in cardiovascular literature. According to the most recent evidence from the American Heart Association published in Hypertension (2023), hypertension significantly increases the risk of myocardial infarction:

• In case-control studies, the odds of myocardial infarction were 5.4-9.5 times higher among individuals with hypertension alone compared to normotensive individuals 1
• A meta-analysis showed that individuals with hypertension had 9.30 times (95% CI 3.89-22.23) higher odds of myocardial infarction compared to normotensive individuals 1
• The Argentine FRICAS study found an adjusted odds ratio of 2.58 (95% CI 2.08-3.19) for acute myocardial infarction due to hypertension 2

Risk Stratification by Hypertension Severity

The risk of myocardial infarction increases with the severity of hypertension:

• For moderate hypertension (highest systolic <200 mmHg): OR 2.42 (95% CI 1.88-3.11) 2
• For severe hypertension (highest systolic >200 mmHg): OR 4.12 (95% CI 2.87-5.89) 2
• For diastolic values <120 mmHg: OR 2.48 (95% CI 1.90-3.24) 2
• For diastolic values >120 mmHg: OR 4.12 (95% CI 2.83-5.99) 2

Blood Pressure Control and MI Risk

The quality of blood pressure control significantly impacts the risk of myocardial infarction:

• Patients with most recent systolic BP ≤140 mmHg: OR 2.59 (95% CI 1.96-3.41) 2
• Patients with most recent systolic BP >140 mmHg: OR 3.42 (95% CI 2.40-4.87) 2
• Patients with most recent diastolic BP ≤90 mmHg: OR 2.48 (95% CI 1.91-3.22) 2
• Patients with most recent diastolic BP >90 mmHg: OR 3.72 (95% CI 2.33-5.96) 2

This demonstrates that even with controlled hypertension, there remains a residual risk of myocardial infarction, though it is lower than with uncontrolled hypertension.

Combined Risk Factors

The risk of myocardial infarction increases substantially when hypertension coexists with other cardiovascular risk factors:

• In smokers without hypertension: OR 2.28 2
• In smokers with hypertension: OR 7.51 2

Sex and Demographic Differences

Hypertension has differential impacts on MI risk based on sex and other demographic factors:

• Women with hypertension have higher rates (69.1%) compared to men (63.4%) in STEMI patients 1
• Hypertension prevalence is approximately double among individuals >75 years versus those <45 years of age in ACS patients 1

Clinical Implications

The high odds ratio of myocardial infarction in hypertensive individuals underscores the importance of:

1. Early detection and aggressive management of hypertension
2. Targeting blood pressure levels below 140/90 mmHg to reduce MI risk
3. Addressing concurrent cardiovascular risk factors, particularly smoking
4. Recognizing that even well-controlled hypertension carries residual risk for MI

The evidence clearly demonstrates that hypertension is not just a risk factor but a major driver of myocardial infarction risk, with odds ratios ranging from approximately 2.5 to 9.5 depending on severity, control, and coexisting risk factors.