The Southall and Brent baseline studies were cross-sectional studies conducted between 1989 and 1991, at a time when the majority of first generation South Asian and African Caribbean migrants to the UK were entering middle age. The studies have generated a number of hypotheses regarding the causes of ethnic group differences in cardiovascular risk factors and the pathogenesis of cardiovascular disease.
The baseline studies were the first to report the high prevalence of the insulin resistance or cardiometabolic syndrome in association with a striking tendency to central obesity in British South Asian migrants- these findings were common to Hindus, Sikhs and Muslims. These results suggested that insulin resistance is the underlying cause of their increased susceptibility to coronary heart disease and stroke (1,2).
African Caribbeans, on the other hand, were as dysglycaemic but less hyperinsulinaemic than South Asians. They were not centrally obese suggesting that the causes of diabetes in African Caribbeans may be different from those in South Asians and this might also explain why coronary heart disease mortality in African Caribbeans is low, despite the high prevalence of diabetes and hypertension (1,2). Their more favourable lipid profiles were thought to be related to body fat distribution (5).
Resting and ambulatory blood pressure recordings in a subgroup of Europeans and African Caribbeans, demonstrated that resting blood pressures were substantially higher in the African Caribbeans and that this may be enough to explain excess stroke mortality in African Caribbean women, but not in men. Smaller declines in nocturnal blood pressure may contribute to the excess of hypertensive target organ damage in African Caribbeans (3).
A presentation about some of these findings:Baseline findings presentation