Table 1.

Changes in Heart Rate Variability Parameters

Variable	Group	Baseline	Distention	Post-meal
%HFa	Controls	49 ± 18	38 ± 18	36 ± 14
	IBS	52 ± 19	42 ± 17	39 ± 16
LF/HF a,b	Controls	1.5 ± 1.1	2.8 ± 2.8	2.8 ± 2.0
	IBS	1.7 ± 2.0	2.0 ± 1.7c	2.6 ± 2.3

^aP < 0.01, period effect by the linear mixed model across the 3 periods.

^bP < 0.05, group × period interaction.

^cP < 0.05, group × period interaction between the baseline and distention periods.

HF, high frequency; LF, low frequency.

Data are shown as mean ± SD.