PREVALENCE OF DIABETES IN ELDERLY PATIENTS REQUIRING PERMANENT CARDIAC-PACEMAKER INSERTION

Diabetes mellitus increases the rate of atrioventricular block after a myocardial infarction; right bundle branch block is more common than expected in the diabetic outpatient population. We decided to assess w hether diabetic subjects were more likely to need permanent cardiac pa cemaker insertion. Data from patients in Leicestershire who had underg one permanent cardiac pacemaker insertion during a 4-year period were analysed. The capture-recapture technique was used: Hospital Activity Analysis data as capture, ward admission book and case note confirmati on as recapture. Diabetes coding accuracy was confirmed from the centr al register and from an analysis of 100 sets of case notes. The number of these patients with diabetes was then recorded. Data for the refer ence population was obtained using a survey of a market town in Leices tershire. There were 688 patients, most (79%) aged over 65 years. Our analysis was performed on this group. Of this age group undergoing pac emaker insertion, 11.1% was diabetic. In the same age group, 8.3% of t he controls were diabetic: a relative risk of 1.34 (P<0.01, 95% confid ence interval 1.25-1.44). This relative risk is likely to be an undere stimate. The aetiology of this excess risk is uncertain; it is most li kely due to ischaemic heart disease, but microangiopathy or increased cholinergic sensitivity may play a role.