Comparison of the smoothness index, the trough : peak ratio and the morning : evening ratio in assessing the features of the antihypertensive drug effect.

OBJECTIVE: To provide a direct comparison of the trough : peak ratio (TPR), the morning : evening home blood pressure ratio (MER) and the smoothness index (SI) in assessing the features of the antihypertensive drug effect. PATIENTS AND METHODS: A total of 27 untreated hypertensives were randomized to receive lisinopril 20 mg o.d. or losartan 50 mg o.d. for 5 weeks and were subsequently crossed-over to the alternative treatment for a second 5-week period. Twenty-four hour ambulatory and 5-day home blood pressure were monitored before randomization and at the end of each treatment period. TPR, MER and SI were calculated for each drug for the total study population and for responders only. RESULTS: When all patients were considered, lisinopril provided higher values of TPR [0.63/0.66 for systolic/diastolic blood pressure (SBP/DBP)], MER (1.02/0.77) and SI (1.01/0.87) than losartan (0.35/0.51, 0.60/0.60 and 0.64/0.53, respectively). Analysis of responders only, again showed a clear advantage of lisinopril over losartan in TPR (0.77/0.67 versus 0.44/0.47, respectively) and MER (0.86/0.87 versus 0.48/0.61), whereas there was no difference in SI (1.25/1.13 for lisinopril versus 1.11/1.12 for losartan). CONCLUSIONS: These data suggest that the assessment of the duration of the antihypertensive drug effect provided by the MER is consistent to that by the TPR and that two drugs with different levels of TPR and MER may have the same level of SI. It appears that the SI is not simply a more reliable index of the features of the antihypertensive drug effect, but offers a different type of information complementary to that provided by the TPR and the MER, in regard to the homogeneity and the magnitude but not the duration of the antihypertensive effect.

Reproducibility of home, ambulatory, and clinic blood pressure: implications for the design of trials for the assessment of antihypertensive drug efficacy.

BACKGROUND: The aims of this study were to compare the reproducibility of blood pressure (BP) measured in the clinic (CBP), at home (HBP), and by ambulatory monitoring (ABP), and to assess its implications on the accuracy of antihypertensive drug trials. METHODS: A total of 133 untreated subjects with elevated CBP were assessed with repeated measurements of CBP (five visits within 3 months), HBP (6 workdays within 2 weeks), and ABP (twice, 2 weeks apart). The reproducibility of CBP (one visit), HBP (2 days), and ABP (24 h) was quantified using the SD of differences (SDD) between repeated measurements. The number of subjects required in a comparative trial of two drugs was calculated for each measurement method. RESULTS: We found that HBP provided the lowest SDD values (6.9/4.7 mm Hg, systolic/diastolic, compared with 8.3/5.6 for ABP and 11.0/6.6 for CBP). For a parallel trial aiming to detect a difference in the effect of two drugs of 10 mm Hg systolic BP, 51 subjects would be required when using CBP compared with 29 using ABP and 20 using HBP (73, 53 and 37 subjects, respectively, for the detection of a 5 mm Hg difference in diastolic BP). CONCLUSIONS: The study shows that HBP seems to have superior reproducibility compared with both CBP and ABP. In addition, HBP can improve the accuracy of antihypertensive drug trials, thereby reducing the sample size required.

Differentiation between patients with acute upper gastrointestinal bleeding who need early urgent upper gastrointestinal endoscopy and those who do not. A prospective study.

OBJECTIVE: To differentiate, among patients presented at the emergency department with acute upper gastrointestinal bleeding, those who need early urgent upper gastrointestinal endoscopy from those who do not. METHODS: Seventeen variables for each patient presenting with upper gastrointestinal bleeding were prospectively recorded and considered in a multivariate analysis. We used the presence of active bleeding during early urgent upper gastrointestinal endoscopy within 12 h from admission as the end point. The derived score was validated with data from the next consecutive patients presenting with upper gastrointestinal bleeding. RESULTS: Among 190 consecutive patients (mean age 63.7 +/- 16 years; 64.7% men), active bleeding was observed in 51 patients (26.8%). Four variables were identified as independent predictors (P < 0.05) of active bleeding in early urgent upper gastrointestinal endoscopy and were used for the derivation of the following integer-based scoring system: number of points = 6 (fresh blood in nasogastric tube) + 4 (haemodynamic instability) + 4 (haemoglobin < 8 g/dl) + 3 (white blood cell count > 12 000/microl). The validation study consisted of 110 patients (71 men; mean age 66.1 +/- 14 years; 28 patients [25.5%] with active bleeding). In this study, a cut off of < 7 points indicated absence of active bleeding and >/= 11 points indicated presence of active bleeding; this gave a sensitivity of 96%, specificity of 98%, positive predictive value of 96% and negative predictive value of 98%. CONCLUSIONS: Simple clinical and laboratory variables available at presentation can be used to differentiate patients with upper gastrointestinal bleeding who do not need an early urgent upper gastrointestinal endoscopy from those who do.