Abstract:
The objective of this study is to evaluate the
effect of exercise on cardiac autonomic function as measured
by short-term heart rate variability (HRV) in females
suffering from rheumatoid arthritis (RA). Females with confirmed
RA were randomly assigned to an exercise group
(RAE) and a sedentary group (RAC). RAE was required to
train under supervision two to three times per week, for
3 months. Three techniques (time domain, frequency domain
and Poincaré plot analyses) were used to measure
HRV at baseline and study completion. At baseline, RAC
(n018) had a significantly higher variability compared to
RAE (n019) for most HRV indicators. At study completion,
the variables showing significant changes (p00.01 to 0.05)
favoured RAE in all instances. Wilcoxon signed rank tests
were performed to assess changes within groups from start
to end. RAE showed significant improvement for most of
the standing variables, including measurements of combined
autonomic influence, e.g. SDRR (p00.002) and variables
indicating only vagal influence, e.g. pNN50 (p00.014).
RAC mostly deteriorated with emphasis on variables measuring
vagal influence (RMSSD, pNN50, SD1 and HF
(ms2)). Study results indicated that 12 weeks of exercise
intervention had a positive effect on cardiac autonomic function as measured by short-term HRV, in females with RA. Several of the standing variables indicated improved
vagal influence on the heart rate. Exercise can thus potentially
be used as an instrument to improve cardiac health in a
patient group known for increased cardiac morbidity.
