The Prevalence of Isolated Systolic Hypertension in Patients 60 Years of Age and Over Attending Australian General Practitioners

Aims: To determine the prevalence of isolated systolic hypertension (ISH) in patients 60 years of age and over attending general practitioners, and the proportion of patients in whom blood pressure (BP) remains within the ISH range when measured on three successive occasions and when using home BP monitoring. Methods: BP was measured in 38 832 patients. Patients categorized as having ISH were reviewed after one week. Patients who had BPs in the ISH range at the second visit were provided with a home BP monitor and attended again in one week's time for further clinic blood pressure measurements. Results: 8.6% of all patients were classified as having ISH and 31.4% as having borderline ISH at the first clinic visit. ISH was twice as prevalent in patients receiving antihypertensive therapy (12.4%) than in those not on antihypertensive therapy (6.2%). Of the patients initially categorized as having ISH, and who attended all three clinic visits and completed the home BP monitoring, 52.3% were confirmed as having ISH, 34.0% fell into the borderline ISH range and only 7.0% had a normal BP reading at the third clinic visit. The use of home BP monitoring produced similar results. Conclusion: ISH is present on first screening in approximately 8% of elderly Australian patients. This prevalence falls by about 50% when BP is measured on two further occasions, with most patients subsequently falling into the borderline ISH range. Home BP monitoring does not reduce the percentage of patients classified as having ISH on the basis of three clinic measurements.