Correlation between blood pressure variability and subclinical target organ damage in patients with essential hypertension.

High blood pressure (BP) variability is associated with the increased risk of cardiovascular and renal damage together with increased cardiovascular mortality. The aim of our study was to investigate the relationship between BP variability and subclinical target organ damage (TOD) in patients with controlled essential hypertension. One hundred patients with controlled essential hypertension were randomly selected from outpatient clinic of Beni-Suef University hospital. All patients were subjected to full history taking, physical examination, three separate office BP measurements for assessment of long-term BP variability, ambulatory BP monitoring for short-term variability, and finally different investigations for subclinical TOD. We had 73 patients with subclinical TOD. Long-term visit-to-visit variability was evaluated by measuring SD (standard deviation) and CV (coefficient of variance) of systolic and diastolic BP. None of the parameters of long-term BP variability were significantly higher among patients with TOD compared with those without TOD. For short-term variability evaluated by ambulatory BP monitoring, average real variability (ARV) was the only parameter that had a significant consistent association with TOD in contrast to SD and CV. Finally, Daytime systolic ARV, nighttime diastolic ARV, and age were independent predictors of TOD (P values = 0.014, 0.018, 0.047, and 0.02, respectively). We concluded that ARV could be an appropriate index of BP variability and a more useful predictor of TOD in contrast to other parameters of BP variability.