Baseline demographics, clinical characteristics, ECG findings and randomized antihypertensive treatment in patients without and with incident LBBB
Clinical characteristic
No new LBBB (n = 8,271)
Incident LBBB (n = 295)
P
Adjusted P*
Female gender (%)
53.6
46.8
0.025
n/a
Age, years
67 ± 7
69 ± 6
< 0.001
n/a
Race, % white
92.2
93.9
0.32
0.63
Height (cm)
167.6 ± 9.4
168.5 ± 9.7
0.152
0.152
Weight (kg)
78.9 ± 14.9
80.9 ± 15.3
0.071
< 0.005
Body mass index, kg/m2
28.0 ± 4.8
28.4 ± 4.9
0.12
< 0.05
Obesity (> 35 kg/m2), %
0.50
0.64
0.18
0.14
Systolic BP, mmHg
175 ± 14
173 ± 14
0.205
< 0.005
Diastolic BP, mmHg
98 ± 9
96 ± 9
< 0.001
< 0.01
Pulse pressure, mmHg
77 ± 16
78 ± 15
0.237
0.190
Heart rate, beats/min
70 ± 13
71 ± 13
0.043
0.164
Serum creatinine, μmol/L
86.7 ± 20.2
89.4 ± 19.1
< 0.05
0.519
Serum glucose, mmol/L
6.01 ± 2.18
6.27 ± 2.22
0.053
0.106
Framingham risk score
22.3 ± 9.4
25.1 ± 9.6
< 0.001
0.150
Sokolow–Lyon voltage, mm
30.0 ± 10.5
30.8 ± 10.7
0.17
0.717
**Cornell product, mm × ms
2,654 ± 764
3,530 ± 1,225
< 0.001
< 0.001
Cornell voltage, mm
26.5 ± 7.5
34.7 ± 12.2
< 0.001
< 0.001
QRS duration, ms
97.2
113.7
< 0.001
< 0.001
Randomized to losartan, (%)
50
50
0.26
0.26
Adjusted for sex and age;
sex-adjusted; BP: blood pressure; n/a: not applicable
Declarations
Acknowledgments
The authors thank the 945 clinical investigators who participated in the LIFE study.
Author contributions
CNB, ZL and PMO contributed to the conception and design of this LIFE sub-study. CNB, ZL and PMO performed the statistical analyses. ZL wrote the first draft of the manuscript. All authors contributed to manuscript revision, read and approved the submitted version.
Conflicts of interest
Sverre E. Kjeldsen has received lecture honoraria within the past 3 years from Getz Pharma, Merck Healthcare KGaA, Sanofi-Aventis and Vector-Intas. The other authors declare that they have no conflicts of interest.
Ethical approval
Ethical committees for all participating clinical centers approved the LIFE study. The study was performed in accordance with the Declaration of Helsinki. The study was chaired by an academic steering committee, and it was overseen by an independent data and safety monitoring board.
Consent to participate
Written informed consent to participate in the study was obtained from all participants.
Consent to publication
Not applicable.
Availability of data and materials
The data that support the findings of this study are available from the corresponding author (PMO) upon dire need.
Funding
Merck & Co., Inc. supported the LIFE study with an unrestricted grant from 1993. Merck had a non-voting member of the Steering Committee, which designed the study and wrote the protocol. Merck did monitoring, and accumulated data in a Merck database until study end in 2002. Merck provided the study steering committee with free access to blinded data until 2002 and then un-blinded data after the database was cleared for queries and frozen. The steering committee including a committee statistician validated independently the main outcomes. The steering committee has always been free to analyze and interpret the data, make decisions to publish and write the papers. Merck has not had any formal role after 2002 except for sporadically providing expert statistical assistance.
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