Page 34 - Physical activity in recipients of solid organ transplantation - Edwin J. van Adrichem

Chapter 2
aerobic exercise potentially leads to oxidative stress.
PA to generate the maximal positive e

e optimal frequency and intensity of
ect in RTR is unknown. For the general population,
it is stated that, in order to generate health bene
44

ts from PA, some PA is better than none,
and more is better than some.
is indicates that every improvement in PA results in a
certain amount of bene t.
For the interpretation of the results of this study, a number of limitations should be
taken into account. First, because of the observational design, this study cannot discern
causality and can only provide direction for further studies. Second, measurements of PA
and cardiac biomarkers were only available at baseline.

erefore, changes over time in
either of the variables could not be accounted for.

ird, the exclusion of patients with
overt heart failure from the original study may limit the extrapolation of these data to the
entire population of RTR. Lastly, although the questionnaires employed to assess PA are
validated and used extensively, bias towards socially desirable answers may still have led to
an overestimation of PA. Major strengths of this study are the availability of data on PA,
cardiac markers to assess cardiovascular health, mortality in a large sample of RTR, and it
is the

rst study to link data on PA, cardiac markers, and mortality in a population of RTR.
In conclusion, the cardiac biomarkers MR-proANP, NT-proBNP, and Hs-TnT are
strongly associated with both CV- and all-cause mortality in RTR. Nevertheless, the
association between PA and CV and all-cause mortality was independent of these markers.
Pre-existent cardiac damage, as measured by cardiac markers, did have a signi

cant
mediation e
32.

ect on the association, implicating cardiac damage as intermediate step of the
causal pathway. Increasing PA levels or maintaining high levels of PA, therefore, appear to
be of the utmost importance in all RTR.