Background:
PR prolongation (pPR, ≥200 ms) is associated with atrial fibrillation (AF). AF leads
to macro- and microembolic embolization which may lead to cognitive dysfunction. The
aim of this study was to investigate the association between cognitive function and
PR interval in individuals with normal (nPR) and pPR intervals and in AF patients.
Methods:
The LIFE-Adult-Study is a population-based cohort study, which has recently completed
the baseline examination of 10.000 randomly selected participants from Leipzig. In
this cross-sectional analysis, individuals ≥40 years with available ECG and cognitive
function data (Verbal Fluency Test „Animals“, Trail-Making-Test/TMT A and B) were
included. Individuals with atrio-ventricular conduction decelerating medication and
psychotropic medication were excluded.
Results:
The study population comprised 4.017 individuals (59 ± 12 years, 49% males) with complete
ECG and cognitive function data. There were 55 AF patients (1.4%) and 142 (3.5%) with
pPR.
No difference was found in verbal fluency among individuals with nPR, pPR and AF (mean
24 ± 6 vs. 24 ± 7 vs. 21 ± 8, p = 0.131 respectively). However, compared to nPR, individuals
with pPR and AF demonstrated worse performance (longer time needed) in the TMT-A (mean
35 ± 14 vs. 41 ± 18 vs. 44 ± 13 s, p < 0.001) and the TMT-B (85 ± 44 vs. 94 ± 46 vs.
107 ± 38 s, p < 0.001).
On univariable linear regression analyses, TMT-A (B = 5.346, 95%CI 2.841 – 7.850,
p < 0.001) and TMT-B (B = 9.648, 95%CI 2.171 – 17.125, p = 0.011) were associated
with pPR. However, after adjustment for age and gender, the results were not significant.
Similar, TMT-A (B = 8.636, 95%CI 4.601 – 12.672, p < 0.001) and TMT-B (B = 23.821,
95%CI 11.192 – 36.450, p < 0.001) were associated with AF only in univariable analysis.
Conclusions:
There is no significant association of pPR and AF with cognitive function in healthy
individuals. Further longitudinal studies are needed to analyze the impact of pPR
and AF on cognitive function in the long-run.
