Association of incident LBBB with clinical endpoints in univariate Cox regression models
Endpoint
No new LBBB, n (%)
Incident LBBB, n (%)
HR (95% CIs)
P
Primary composite endpoint
988 (25.8)
28 (19.7)
2.68 (1.83–3.92)
< 0.001
Stroke
502 (12.9)
6 (4.0)
1.17 (0.52–2.64)
0.700
Myocardial infarction
360 (9.2)
5 (3.3)
1.25 (0.51–3.04)
0.624
CV mortality
364 (9.0)
21 (13.2)
4.33 (2.76–6.80)
< 0.001
Sudden cardiac death
564 (14.6)
7 (4.8)
3.07 (0.96–2.08)
0.080
Hospitalization for heart failure
264 (6.7)
12 (8.4)
4.95 (2.74–8.94)
< 0.001
All-cause mortality
705 (17.7)
34 (21.6)
3.40 (2.40–4.80)
< 0.001
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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