Hypertension is the most important risk factor for cardiovascular diseases (CVD), accounting for approximately 45% of global CVD morbidity and mortality.1 Evidence suggests striking differences in blood pressure (BP) and hypertension prevalence between ethnic groups. West African descent adults living in Europe and North America, whether they come directly from Africa or indirectly from the Caribbean, generally have higher BP levels and a higher prevalence of hypertension than European descent populations (henceforth, white individuals), with this being seen at all ages in North America and only from adulthood in the UK.2 ,3 Chinese-origin people also have slightly higher BP and prevalence of hypertension than white individuals.4 ,5 The evidence is mixed when it comes to the South-Asian descent populations (ie, Indian, Pakistani, Bangladeshi and Sri Lankan people). In a systematic review in the UK, BP levels among South-Asian individuals were generally similar to that of the UK general population, but there were stark differences among the South-Asian subgroups, with slightly higher BP in Indian individuals, slightly lower BP in Pakistani individuals, and much lower BP in Bangladeshi individuals.6 Studies in The Netherlands7 and Canada,5 ,8 however, show a higher hypertension prevalence in South-Asian than in white individuals. In the Ontario Health Survey, the age-standardised hypertension prevalence among South-Asian individuals was 30.1% compared with 20.7% among white Canadian people.8 South-Asian were still more likely than white Canadian individuals to have hypertension even after adjustment for age, sex and body mass index.

While hypertension remains the most important risk factor for CVD, its contribution to the ethnic differences in CVD outcomes is still sometimes puzzling. In the UK, although the BP levels are similar or lower in the South-Asian relative to the general population, they have a higher mortality from stroke and …