Effect of Losartan on Ambulatory Blood Pressure in Hypertensives

Objective To investigate the effect of losartan on ambulatory blood pressure(ABP) in hypertensives. Method 20 cases essential hypertension(EH) were treated with losartan(50mg qd,at 7:00am) for 24 weeks. The ABP measured before and after treatment. The BP decreased at the end of the dose interval(trough) to the most large BP descreased in the dose interval(peak) served as the ratio of trough∶peak(T∶P) of the drugs. Results (1)Losartan had hypotensive effect with the efficacy of 85.0%. (2)T∶P ratio of losartan was 78.6±15.4 for SBP and 76.2±14.7 for DBP. Smoothness index of SBP, DBP and MBP was 1.23±0 32,1.36±0 41 and 1.32±0 38, respectively.(3)In hypertensives with nighttime BP higher than normal(120/80 mmHg). Losartan was significantly decreased nighttime BP(SBP from 143±9 to 116±11 mmHg,\%P\%0 01,DBP from 89±10 to 74±7mmHg,\%P\%0 01). In hypertensives with normal nighttime BP,losartan didn't decrease BP further(\%P\%0 05).(4)The 24 h average decreased extent of SBPand DBP after treatment was positively correlated to SBP and DBP before treatment ( r =0 803 and 0 797,respectively, \%P\%0 01). Conclusion The main advantage of losartan is to decrease steadily 24 h BP and inhibit the elevation of morning BP significantly, no danger of excessive decrease of BP in nighttime.