Orthostatic hypotension predicts vascular death in older diabetic patients

Diastolic orthostatic hypotension measured 1 min after standing up (OH-D1), and systolic OH measured 3 min after standing up (OH-S3) increase vascular mortality risk among older adults. We hypothesized that the risk is especially high among diabetic patients. The orthostatic test was carried out in a standard way by a trained nurse in 868 subjects (79% of a representative population sample) and 98 of them were diabetic treated with oral hypoglycemic agents or insulin. OH-D1 occurred in 9 (9%) diabetic patients and in 43 (6%) other subjects of the cohort (Chi-Square; P = 0.157), and OH-S3, correspondingly, in 28 (29%) and 140 (18%) (P = 0.014). Absent patellar vibration sense, absent patellar reflex and resting heart rate was higher, and cardioacceleration early after active standing up was lower in the diabetic patients. According to Cox Proportional Hazards modelling, after adjustment for other baseline variables (age, sex, history of myocardial infarction, current smoking, chest pain and systolic blood pressure), the hazard ratio of vascular death as regards OH-D1 was 3.69 (95% confidence intervals 1.54-8.84), and that as regards OH-S3 was 2.70 (1.16-6.29). Among the persons free of diabetes treated with oral hypoglycaemic agents or insulin (N = 770), survival for vascular death did not differ in regard to presence and absence of OH-D1 and OH-S3. Our results suggest that diabetes patients with orthostatic hypotension carry a high risk of vascular death. Diabetic neuropathy is a plausible explanation to our findings.