Ethnic differences in risks of adverse reactions to drugs used in cardiovascular medicine

Some ethnic groups may be more susceptible to adverse drug reactions, finds a study published online in the British Medical Journal.

Adverse drug reactions (ADRs) are an important cause of ill health and death. Several factors including genetic make up, age, sex, and even diet, can all alter a patient's susceptibility to ADRs. But it is not known to what extent susceptibility to ADRs might depend on ethnic group, whether as a result of genetic or cultural factors.

Researchers searched the scientific literature and identified 24 studies that included data for adverse reactions to cardiovascular drugs for at least two ethnic groups. Differences in study quality were assessed to identify and minimise bias.

They found that the risk of angio-oedema (swelling) with blood pressure lowering drugs was three times greater in black patients than non-black patients. The risk of cough was also nearly three times higher in East Asian patients compared with white patients.

For clot-busting therapy, the risk of bleeding increased 1.5-fold in black compared with non-black patients.

Some ethnic groups may be more susceptible to adverse reactions during treatment with cardiovascular drugs, say the authors. These findings may help doctors present more accurate and relevant data to their patients when prescribing cardiovascular therapy. However, differences in study quality and inconsistent reporting of harms mean that these results need to be interpreted cautiously, they add.

Future studies must report both adverse reactions and racial and ethnic classifications more fully, if we are to discover how they are linked, they conclude.