Introduction
The health-care scenario has undergone remarkable changes during the past 50 years. Take the case of IHD, for example.
Treatment of established IHD involves the life-long medication, investigations, hospitalization, and operations such as coronary angioplasty and coronary artery bypass surgery. All these facilities come at a high price.
Over the past half a century or so, it has been proved beyond doubt that if we address the key risk factors for IHD, we can drastically bring down the number of new patients who present with IHD. The health care system registries of Europe and the US stand as testimony to the success of the preventive approach. We have in our possession facts and figures which indicate the risk of heart attack and death in people who have received certain forms of treatment, versus those who have not. Therefore, the modern clinical approach is less subjective and more objective.
Risk Stratification
It has been found that person with only one risk factor for CVD is far less likely to have an event such as a heart attack than one who has multiple risk factors. Several protocols have been proposed to assess an individual’s risk, of which the one that has been published by the European Society of Cardiology has been shown below. This is the Systemic COronary Risk Estimation (SCORE) system (1).
Very high risk:
These are the subjects having documented CVD, T2DM or T1DM with one or more CV risk factors or target organ damage. SCORE >= 10%
High risk:
These are the patients with markedly raised isolated risk factors such as familial dyslipidemia, very high blood pressure levels, T2DM or T1DM without CV risk factors or target organ damage, moderate chronic kidney disease (eGFR 30-59 mL/min/1.73 m2). SCORE 5-10%.
Moderate risk:
These are the patients who are physically inactive, have abdominal obesity, have a family history of IHD, belong to a deprived social class, or have high triglycerides, high hsCRP, or low HDL(c) levels. SCORE < 5% and >= 1%.
Low risk:
These subjects do not have any of the qualifiers mentioned in the categories described above. SCORE <1%.
The total CVD risk is the sum total of the risk caused by each of the risk factors. The patients who have established CVD are classified under the very high risk category. For all the rest, there are computer algorithms or charts to delineate the risk.
The good news is that the subjects with the highest risk tend to derive the most benefit from intensive treatment.
Drawbacks of the Risk Assessment System
We started the discussion with the history of a man in this mid 20s who came for a consultation.
While we have discussed the risk scoring system, it is recognised that it under-estimates the risk in young persons, those with a sedentary life style, those with an abdominal obesity, ethnic minorities, those with pre-clinical atherosclerosis, and those who have diabetes mellitus or impaired glucose tolerance. People having low levels of high density lipoprotein cholesterol, high triglycerides, increased apolipoprotein B, increased lipoprotein a, and increased fibrinogen are also under-estimated by this system. But this is all that our medical science can give at the present moment.
Women have the same susceptibility to have heart attacks as men, but they tend to have them a decade or so later.
We in India use the risk calculators that were developed in Europe and the US. Till now, there are no widely accepted risk calculators for the Indian patients. It is known that Indians have an earlier onset of IHD, and the disease is more severe than the western people at the time of presentation.
Suggested reading:
European Society of Cardiology, European Association of Cardiovascular Prevention & Rehabilitation. HeartScore. [Online]
http://www.heartscore.org/Pages/welcome.aspx
