Diabetes in a Caribbean population: epidemiological profile and implications

To examine the distribution and impact of diabetes, glycaemic status, and related factors, in a predominantly black adult Caribbean population.

The study included 4709 people, or 84% of a simple random sample of Barbadian-born citizens aged 40-84 years, examined between 1988 and 1992 and re-assessed 4 years later. Diabetes was evaluated according to physician-diagnosis and glycosylated haemoglobin (GHb). Associations were assessed by logistic regression analyses, cumulative mortality by product-limit methods and death-rate ratios by Cox proportional hazards regression.

Among the 4314 black participants, the prevalence of known diabetes, predominantly type 2, was 9.1% at 40-49 years of age and increased to 24.0% at 70-79 years. The overall prevalence was 17.5%, while it was 12.5% in mixed (black/ white; n = 184) and 6.0% in white/other participants (n = 133), only 0.3% had younger-onset. Additionally, 2% had GHb >10% (>2 SD over the mean) without diabetes history. Sulphonylureas were the most frequent treatment, while insulin use was infrequent. In black participants, diabetes was positively associated with age (OR = 1.03 per year; 95% CI : 1.02-1.04), diabetes family history (OR = 2.85, 95% CI : 2.39-3.40), hypertension (OR = 1.71, 95% CI : 1.42-2.05), obesity (BMI > or = 25 kg/m(2); OR = 1.74, 95% CI : 1.44-2.10), and high waist-hip ratio (WHR > or = 0.92; OR = 1.29, 95% CI : 1.09-1.53). Ocular co-morbidities were increased among people with diabetes, as was 4-year-mortality (death rate ratio = 1.42, 95% CI : 1.10-1.83). There was a 9% increase in mortality for each 1% increase in GHb (death rate ratio = 1.09, 95% CI : 1.04-1.15).

A markedly high prevalence of diabetes existed in the adult black population, affecting almost one in five people and increasing morbidity and mortality. Prevention strategies are urgently needed to reduce the adverse implications of diabetes in this and similar populations.