Risk Factors for Coronary Artery Disease in Indians

A case control study was carried out to study the emerging risk factors for coronary artery disease in Indians.

The diagnosis of coronary artery disease was based on correlation of clinical, biochemical, electrocardiography, echocardiography, treadmill testing and coronary arteriography findings. The study comprised 100 cases of coronary artery disease (acute coronary syndrome and chronic coronary artery disease) and 100 controls in two tertiary care service hospitals. The subjects were evaluated for total plasma homocysteine, insulin, C-reactive protein (CRP), lipoprotein fibrinogen and anti-chlamydial anti-bodies.

Male to female ratio was 10:1 in study group with similar predominance of males in controls. Mean age of the cases was 47 years (range 25-59 years) and that of controls was 43 years (range 23-56 years). 64% cases had acute coronary syndrome and 34% had chronic coronary artery disease. In the coronary artery disease population, 76% cases had hyperhomocyteinemia, 9% hyperinsulinaemia, 11% abnormal CRP values, 23% abnormal lipoprotein (a) levels, 40% IgG anti-chlamydial anti-bodies and only 11% had Ig M anti-chlamydial antibodies. In the control population, 72% had hyperhomocystinaemia and 6% hyperinsulinaemia while 23% and 9% controls had IgG and IgM anti chlamydial antibodies respectively. In control group 19% cases had abnormal lipoprotein(a) levels and only 2% had abnormal C reactive protein values. Significant correlation of CAD was seen with CRP values and Ig G anti-chlamydial antibodies. Both the study group and controls had higher homocysteine levels than that observed in some Indian and Western studies.

High C reactive protein levels and Ig G anti-chlamydial antibodies are associated with coronary artery disease in Indians. Insulin, lipoprotein A, fibrinogen, lgM anti-chlamydial antibodies and higher levels of total plasma homocysteine have no significant association with coronary artery disease.