Page 24 - Physical activity in recipients of solid organ transplantation - Edwin J. van Adrichem

Chapter 2
Abstract
Background and objectives
Design, setting, participants, and measurements
Mortality was recorded until May 2009.
Results
Low levels of physical activity (PA) in renal transplant recipients (RTR) are strongly
associated with an increased risk of cardiovascular and all-cause mortality. Potentially, these
associations are partly explained by pre-existing cardiac damage. We investigated whether
the associations are in

uenced by markers of ventricular wall strain and cardiac ischemia.

is study is a post-hoc analysis of data from 540 RTR (age 51 ± 12 years, 54% male) who
were included between 2001 and 2003. PA was assessed with questionnaires resulting in
metabolic equivalents of task minutes per day (MET-min/d). Cardiac markers mid-
regional pro-atrial natriuretic peptide (MR-proANP), N-terminal-pro brain natriuretic
peptide (NT-proBNP), and high sensitive troponin T (Hs-TnT) were determined.

e average MET-min/d was 117.1[26.5; 294.3], and 52% of RTR complied with PA
guidelines. Cardiac markers were inversely associated with PA level. During follow-up after
6.9[6.2-7.2] years, 117 (22%) patients had deceased with 63 deaths being cardiovascular in
origin. In Cox regression analyses, MR-proANP (HR=1.62[1.42; 1.83]), NT-proBNP
(HR=1.51[1.36; 1.68]), and Hs-TnT (HR=1.36[1.21; 1.53]) were associated with
cardiovascular mortality. Similar associations were ascertained for all-cause mortality.
Lower PA levels were strongly associated with cardiovascular and all-cause mortality and
the associations were independent of potential confounders including cardiac markers
(HR=0.87[0.79; 0.95] and 0.92[0.86; 0.98], respectively).
mediated ranging from 21% to 33%.
Conclusion
cardiac markers and a lower mortality risk.

e markers were signi

cant
mediators of the association between PA and cardiovascular mortality with proportions
In RTR, low PA and high levels of MR-proANP, NT-proBNP,
associated with increased mortality.

e cardiac markers had a signi
and Hs-TnT are strongly

cant mediation e

ect
on the association between PA and outcome, implicating pre-existing cardiac damage as
intermediate step of the causal pathway. RTR with high levels of PA had lower levels of
22.