Blood pressure levels, risk factors and antihypertensive treatments: lessons from the SHEAF study.

objectivesThe SHEAF study (Self measurement of blood pressure at Home in the Elderly: Assessment and Follow-up) is a 3-year prospective cohort study of French elderly (> or =60 years) hypertensive patients designed to assess whether home blood pressure (HBP) measurement provides additional prognostic information over office blood pressure (OBP) in terms of cardiovascular mortality and morbidity. The objective of the present work is to describe the baseline data of the population enrolled in the SHEAF study with special emphasis on blood pressure control in treated hypertensives.

methodsDuring the 2-week initial inclusion phase, baseline demographics, cardiovascular risk factors, antihypertensive treatments as well as office and home blood pressure were recorded. Baseline OBP was assessed using a mercury sphygmomanometer (three consecutive measurements during two visits performed 2 weeks apart). HBP was performed over a 4-day period (three consecutive measurements in the morning and in the evening).

resultsA total of 4939 (95%) of the 5211 patients included in the SHEAF study were treated with at least one antihypertensive drug. Their ages ranged from 60 to 99 years (mean age 70 +/- 7 years); 49% were men, 12% had a previous history of coronary artery disease, 14% diabetes and 43% a treated dyslipidaemia. A total of 45% of the treated patients received a single antihypertensive drug, 34% two drugs, 21% three drugs or more. Overall 23% of treated hypertensives were normalised at the doctor's office (systolic BP <140 mm Hg and diastolic BP <90 mm Hg) and 27% at home (home systolic BP <135 mm Hg and home diastolic BP <85 mm Hg). Poor blood pressure control was associated with age, an increasing presence of diabetes and prescription of several antihypertensives. The proportion of subjects with controlled blood pressure decrease with age from 26% (60-69 years) to 21% (> or =80 years). Blood pressure control of diabetic patients was particularly poor as only 19% had an OBP <140/90 mm Hg and 6% a blood pressure <130/85 mm Hg. The percentage of patients with controlled OBP decreased from 26% when receiving a single antihypertensive drug to 11% when receiving four antihypertensives or more.

conclusionIn the SHEAF study, less than one-third of the patients had an OBP adequately controlled thus confirming previous studies performed in younger populations. Presence of associated cardiovascular risk factors including diabetes did not give rise to a better blood pressure control. When blood pressure control was assessed using HBP measurement similar results were found. As the beneficial effect of antihypertensive treatment has been particularly well established in the elderly, the data of this study underlines the need for a closer and more rigorous management of elderly hypertensives.