Blood pressure, haemorrhagic stroke, and ischaemic stroke: the Korean national prospective occupational cohort study

Abstract
The Korean National Health System for public servants and teachers provides medical expenses and biennial multiphasic health examinations at which blood pressure is measured in the seated position by trained staff using a standard mercury sphygmomanometer (fifth Korotkoff sound used for diastolic pressure) or an electronic manometer.5 We grouped mean blood pressures for individuals between 1986 and 1996 according to the joint national committee on prevention, detection, and treatment of high blood pressure categories of normal, stages 1, 2, and 3 (table). We included deaths attributed to ICD-10 (international classification of diseases, 10th revision) codes of I60-I69 for all strokes, I61 for haemorrhagic stroke, and I63 and I67.8 for ischaemic strokes between 1991 and 2000 in these analyses. We categorised non-fatal strokes using data on the use of medical care and found an accuracy of 83.4% and 85.7% for ischaemic stroke and haemorrhagic stroke.