#98 Is Diabetes a Coronary Heart Disease Equivalent?
CLINICAL QUESTION
Do patients with diabetes have the same risk of cardiovascular (CV) events as patients with existing coronary heart disease (CHD)?
BOTTOM LINE
Though diabetes does confer an increased risk of CV events, it is not automatically equivalent to having experienced a myocardial infarction (MI) (and thus does not always warrant aggressive pharmacotherapy). CV risk should be predicted, and therapy guided, by taking into account individual risk factors.
Reading Tools for Practice Article can earn you MainPro+ Credits
Join NowAlready a CFPCLearn Member? Log in
EVIDENCE
Meta-analysis1 of 13 observational studies (45,108 patients):
- Compared with patients with previous MI, diabetic patients have half the risk of CHD.
- Odds ratio 0.56 (95% confidence interval 0.53-0.60).
- After adjusting for some cardiac risk factors, socioeconomic status, and CV drugs:
- Diabetics had lower risk of MI or coronary death (hazard ratio 0.63 in men and 0.54 in women) than patients with prior MI.
- Limitations: No adjustment for most traditional risk factors (blood pressure, smoking status, etc.), which would have likely attenuated the association in diabetics further.
- Diabetes: 1.70 (1.66-1.74);
- Diabetes duration >10 years: 2.7 (2.6-2.8);
- Prior CHD: 2.76 (2.69-2.85);
- Both diabetes and prior CHD: 3.91 (3.78-4.05).
- North American guidelines4,5 no longer equate diabetes to existing CHD.
- Canadian cholesterol guidelines4 classify diabetics with ≥1 of the following as high-risk patients who may benefit from a statin:
- Age ≥40 years;
- Age ≥30 years and duration of diabetes >15 years; or
- Microvascular disease (nephropathy, neuropathy, retinopathy).
- The observational study6 that originally generated the concept of diabetes-CHD equivalence had multiple limitations, including selection bias and being very underpowered.
- Presence of diabetes approximately doubles the risk of CV events:3,7
- Associated risk further increased by longer duration of diabetes,3,8 increasing HbA1c,9 and traditional cardiac risk factors.10
- Most studies were completed in White individuals, and the applicability of this evidence to high-risk ethnic populations is unclear.
Latest Tools for Practice
#364 Facing the Evidence in Acne, Part II: Oral Antibiotics
How effective are oral antibiotics in treating acne of at least mild-moderate severity?
#363 Making a difference in indifference? Medications for apathy in dementia
In patients with dementia, how safe and effective are stimulants, antidepressants, and antipsychotics for treating apathy?
#362 Facing the Evidence in Acne, Part I: Oral contraceptives and spironolactone in females
How effective are combined oral contraceptives (COC) and spironolactone for treating acne of at least mild-moderate severity in females?
