Wave 1: 1988-91
The original Southall and Brent baseline studies were conducted between 1989 and 1991, at a time when the majority of first generation South Asian and African Caribbean people who had migrated to the UK were entering middle age. The studies have shown that different ethnic groups experience different risks of cardiovascular disease and diabetes and explored the reasons for this.
The baseline studies were the first to report the high prevalence of high fasting blood glucose, high fasting insulin (together termed insulin resistance), diabetes and abdominal obesity in British South Asians – these findings were common to Hindus, Sikhs and Muslim participants.
These studies also suggested that these may be important factors in high rates of coronary heart disease and stroke in South Asian people.
African Caribbean participants also tended to have high fasting blood glucose and had more diabetes and hypertension (high blood pressure) than European participants, but they had lower levels of fasting insulin than South Asians. They also had less abdominal obesity suggesting that the causes of diabetes in African Caribbeans might be different from those in South Asians. This might also explain why coronary heart disease mortality in African Caribbean people is low, despite the high prevalence of diabetes and hypertension. We also showed that the high risk of stroke in people of African Caribbean ethnicity may be explained by the excess of diabetes and hypertension, at least in women.