AIMS

To determine the prevalence and risk factors for stroke in patients with Type 2 diabetes mellitus (T2DM) and the age-specific prevalence odds ratios (POR) in comparison with the general population in Taiwan.

METHODS

A total of 16 994 T2DM patients were randomly selected for telephone interview from a group covered by the National Health Insurance programme. Lifetime prevalence of stroke was calculated and various risk factors were analysed. Age-specific POR was calculated using previously reported prevalence of stroke in the general population from a nationwide survey across Taiwan. Standardized prevalence and POR were also calculated using the 2000-2025 population of the World Health Organization.

RESULTS

A total of 12 531 cases (73.7%) were successfully interviewed. Stroke prevalence was 7.5%. In multivariate logistic regression, independent predictors were: increasing age, male gender, lower body mass index, ex-smokers, hyperlipidaemia, systolic pressure (or diastolic pressure when systolic pressure was not adjusted), education level below high school, and living in eastern or southern Taiwan. When compared with the general population, POR for stroke in the age groups < 45, 45-54, 55-64 and > or = 65 years were 82.29 (9.60, 705.57), 5.43 (2.33, 12.68), 3.73 (2.20, 6.33) and 2.14 (1.59, 2.89), respectively. The age-standardized prevalence of stroke was 2.3% in the diabetic patients and 0.6% in the general population.

CONCLUSIONS

Stroke prevalence in Taiwanese T2DM is 7.5%. Diabetic patients have a higher risk of stroke than the general population, but the relative risk attenuates with age. Besides conventional atherosclerotic risk factors, stroke patients in Taiwan are characterized by lower body mass index, lower education level and residence in southern or eastern Taiwan. The negative association between body mass index and stroke in Taiwanese T2DM is in contrast to the generally accepted concept that obesity is a major risk factor as seen in most western countries.