Random Prescriptions of Aspirin for primary prevention of heart disease may put patients at bleeding risk unless individualized- Hence Individualized, NOT Random Prescription of Aspirin the Need of the Hour- Dr Ashok Seth
The New AHA/ACC guidelines are out and indeed they spell a change in prescription patterns when it comes to Aspirin. I would like to start by saying that before we accept American guidelines on their face value we must remember that the trials were done on Caucasians and other communities in USA but not in India.
Talking about Aspirin, in particular, the reason aspirin is so commonly presented even after 170 years of its discovery is due to its universal availability and also it is the cheapest drug proven to prevent Trans ischemic attacks, strokes, unstable angina and myocardial infarctions. These cerebrovascular and cardiovascular events are the biggest cause of morbidity and mortality across the world.
The issue is that, because it is cheap and easily available over the counter –it is often misused and overprescribed. We must remember that it also has a harmful side effect. We know for long about the bleeding risk from aspirin- it causes gastric erosions and ulcers leading to GI bleed, it can cause intracranial bleeds, which may be life-threatening or less serious bleed like bruising, epistaxis and haematomas after trauma.
The over-prescription and/or inappropriate prescription of aspirin for primary prevention in those who have not been proven to have coronary artery disease, strokes or heart attacks have been on the unproven assumption of its proven benefits in secondary prevention of vascular events. What we need to realize is that -just because it’s cheap and easily available, its risks may outweigh the benefits for primary prevention.
Over the last five years, an increasing number of trials for primary prevention have been done. Two landmark trials were published last year ARRIVE and ASCEND. These trials looked at moderate risk population and diabetics, who were not known to have a vascular disease but had a high chance of having a heart attack/stroke/ unstable angina in the coming years. These trials found that the bleeding risks of Aspirin outweighed any marginal benefits if any of preventing vascular events. Thus, the net result of it to the patient was either no benefit or even harm.
The recommendations that we see have come out based on these trials. Having said that it doesn’t mean that aspirin is useless, it also doesn’t mean that aspirin is categorically harmful.
All it means that Aspirin functions in a narrow risk vs benefit ratio. In patients at high risk for vascular events but with low bleeding risk, the benefits would outweigh the risk. On the other hand, any patient at low risk of vascular events but who has a high bleeding risk (like elderly, previous GI bleeds, patients on NSAID etc.), the risk outweighs the benefits. In summary, an inappropriate prescription of Aspirin in a population at low risk for coronary artery disease is not beneficial. Further, for moderate and high-risk population, if it is in a person with high bleeding events, it could be harmful yet for a person with low risk for bleeding events it could be beneficial.
I want to emphasize that lifestyle modification like exercise, diet, losing weight, better control of diabetes and guidelines based statin use have a greater safety profile and have greater proof of benefits with fewer risks.
Thus to summarize, for primary prevention of vascular events, the emphasis is on (a) lifestyle modification followed by (b) guideline directed statin use and (c) individually tailored Aspirin therapy.
Lets understand with an example- if I have a person who is a smoker, has a family history of CVD and is obese, diabetic but is 42 years and therefore is a low bleeding risk, I perhaps would use aspirin because he has a high risk of an MI but is at a low bleeding risk. But if he is 80 years old with the same risk factor profile then I may not be using Aspirin, unless, coronary artery disease was demonstrated and documented.
That’s why tailoring to the needs is very important. The issue is a WARNING- that don’t use Aspirin unnecessarily and inappropriately for primary prevention in intermediate risk population who are at high bleeding risk and in low-risk population, it is of no benefit anyway.
But in the Indian context, there is a bigger dilemma; Indians are a high-risk population at 2.5 times the risk of developing CAD & MI compared to western countries even when equated for risk factor profiles. We well know the risks of metabolic syndrome X amongst Indians. India is the ‘heart attack capital’ of the world; it is possible that the risk versus benefit ratio of Aspirin could be towards benefit in the high-risk India population keeping in mind that it is a cheap drug for prevention of vascular events in high-risk population.
Thus, it is imperative that we have trials on Indians for the primary prevention and maybe we can show risk vs. benefit in a favourable manner in the Indian population. A low-cost preventive strategy in Indians could decrease the burden of heart attacks and strokes and its subsequent financial burden on patients and healthcare.
To conclude: For primary prevention with Aspirin in India –
- Firstly, we should use Aspirin judiciously and safely tailoring it to patients needs and not randomly.
- Secondly, we need to keep in mind that Indians are at a high-risk coronary artery disease than the western population and therefore should have a lower threshold for use of Aspirin and in those with a moderate risk of CAD and stroke especially if they have a low bleeding risk.
- Thirdly, individualize it to the patient.
As far as secondary prevention is concerned, the benefits of Aspirin are well proven and outweigh the risk largely.
Finally, a doctor should keep in mind that these drug therapies in the guideline are not in lieu of the lifestyle modifications, weight reduction and good eating habits, better control of diabetes, not smoking, control of BP and regular exercise. These perhaps are the most effective and cheapest therapy for prevention of heart attacks and strokes with greatest demonstrated benefits and no side effects.
The author, Dr Ashok Seth is a leading Cardiologist and the current Chairman of Fortis Escorts Heart Institute, New Delhi as well as Head, Cardiology Council of Fortis Group of Hospitals. His contributions in the field of Cardiology, especially Interventional Cardiology have been recognized extensively in India as well as across the world.