Assessment of drug efficacy using home self-blood pressure measurement: the SMART study. Self Measurement for the Assessment of the Response to Trandolapril.
The SMART study (Self Measurement for the Assessment of the Response to Trandolapril) was a large scale trial conducted by general practitioners in order to assess the informative value of home self-measured blood pressure (BP) for the evaluation of therapeutic intervention. After a 2-week wash-out period, patients with office diastolic blood pressure (DBP) between 95 and 120 mm Hg received trandolapril, 2 mg once daily for 4 weeks. Four days of self-recorded BP were performed both at the end of the wash-out period and at the end of the treatment period with an automatic printerequipped device using the oscillometric method (A&D UA 751). Every day, a series of three consecutive measurements was planned in the morning before drug intake and repeated in the evening. A total of 1710 patients (946 men, 764 women) aged 56 +/- 11 entered the study. In the 816 patients who correctly performed self-measured blood pressure (SMBP) during both periods and followed the protocol schedule, office BP (SBP/DBP) decreased from 166.4 +/- 15/101.4 +/- 6 mm Hg to 144.7 +/- 14/86.1 +/- 8 mm Hg while SMBP decreased from 153 +/- 18/94 +/- 10 mm Hg to 139 +/- 16/85 +/- 10 mm Hg. A weak correlation was found between the two methods with regard to systolic (r = 0.47, P < 0.0001) and diastolic (r = 0.36, P < 0.0001) BP lowering. Individual response to therapy varied between the two methods: 633 patients (77.6%) exhibited at least a 10 mm Hg office DBP decrease while 493 (60.4%) presented at least a 6 mm Hg self measured DBP decrease in the evening; 65% of patients were considered as responders with both methods. The 24-h therapeutic coverage was assessed by the morning to evening BP decrease ratio (M/E ratio) which represents the ratio of the trough effect to the 12-h post dosing efficacy. Both population and individual M/E ratios ranged between 73% and 86% thus confirming the long duration of action of trandolapril.


CONCLUSIONS
(1) discrepancies between office and self-measured BP evaluation of therapeutic response have been pointed out: agreement between the two methods is obtained in only 65% of patients, mainly due to intra-individual BP variability and recording conditions; and (2) self-measured BP could be a potential tool to explore the 24-h therapeutic coverage.
Zannad
F
F
Hôpital Central, Nancy, France.
Vaur
L
L
Dutrey-Dupagne
C
C
Genès
N
N
Chatellier
G
G
Elkik
F
F
Ménard
J
J
D000293:Adolescent; D000328:Adult; D000368:Aged; D000806:Angiotensin-Converting Enzyme Inhibitors / Q000627:therapeutic use*; D000959:Antihypertensive Agents / Q000627:therapeutic use*; D001795:Blood Pressure Determination; D005260:Female; D006801:Humans; D006973:Hypertension / Q000188:drug therapy*; D007211:Indoles / Q000627:therapeutic use*; D008297:Male; D008875:Middle Aged
D000806:Angiotensin-Converting Enzyme Inhibitors; D000959:Antihypertensive Agents; D007211:Indoles; C052035:trandolapril