Autonomic changes in fibromyalgia: Clinical and electrophysiological study

Peer review under responsibility of Alexandria University Faculty of Medicine.

Available online 14 March 2012

Figures & data

Table 1 The determined cutoff points of the studied autonomic variables of the control group.

Parameters	Upper limit	Lower limit
Supine systolic BP (mmHg)	142.45	87.21
Supine diastolic BP (mmHg)	93.87	55.47
Supine HR (beat/min)	79.63	63.83
Standing systolic BP (mmHg)	131.05	76.29
Standing diastolic BP (mmHg)	83.82	50.18
Standing HR (beat/min)	102.47	75.39
SSR
Latency (s)	1.81	0.85
Amplitude (μV)	142	41.22

BP: blood pressure, HR: heart rate, SSR: sympathetic skin response.

Table 2 Comparison between patients and controls regarding the assessment of autonomic dysfunction of fibromyalgia.

Parameters	Patients		Controls		t	p
Supine systolic BP (mmHg)
Range	90.0–140.0		90.0–140.0		0.262	0.795
Mean ± SD	114.20 ± 13.04		115.33 ± 13.56
Median	110.00		110.00
Supine diastolic BP (mmHg)
Range	60.0–90.0		60.0–90.0		0.023	0.982
Mean ± SD	74.60 ± 8.89		74.67 ± 9.15
Median	80.00		70.00
Supine HR (beat/min)
Range	63.0–85.0		66.0–77.0		0.673	0.505
Mean ± SD	70.52 ± 6.25		71.73 ± 3.95
Median	70.00		70.00
Standing systolic BP (mmHg)
Range	60.0–130.0		70.0–120.0		2.366^*	0.023
Mean ± SD	92.40 ± 15.078		103.67 ± 13.69
Median	90.00		100.00
Standing diastolic BP (mmHg)
Range	50.0–70.0		50.0–80.0		2.648^*	0.012
Mean ± SD	60.0 ± 7.90		67.0 ± 8.41
Median	60.00		65.00
Standing HR (beat/min)
Range	68.0–90.0		80.0–100.0		4.211^*	0.001
Mean ± SD	78.80 ± 7.70		88.93 ± 6.77
Median	77.00		90.00
Tilt table test	Number	%	Number	%
Negative	9	36.0	15	100	–	–
Positive	16	64.0	0	0.0

BP: blood pressure, HR: heart rate, SSR: sympathetic skin response.

* p is significant at 0.05 or less.

Table 3 Comparison between patients and controls regarding the SSR of the hands.

SSR	Patients (25 hands)	Controls (15 hands)	t	p
Latency (s)
Range	0.50–3.63	1.0–1.98	3.929^*	0.001
Mean ± SD	2.21 ± 0.96	1.33 ± 0.24
Median	2.31	1.29
Amplitude (μV)
Range	0.0–110.0	60.0–132.0	6.466^*	0.001
Mean ± SD	28.31 ± 32.62	92.0 ± 25.39
Median	20.00	89.00

SSR: sympathetic skin response.

* p is significant at 0.05 or less.

Table 4 Correlation between the different questionnaires.

Parameters	r	p
MPQ T PRI
• VAS sleep amount	−0.486^*	0.014
• HRSD	0.693^*	0.001
• FIQ	0.546^*	0.005
MPQ PPI-VAS
• HRSD	0.483^*	0.014
MPQ overall pain intensity
• HRSD	0.520^*	0.008
VAS amount of sleep
• HRSD	−0.449^*	0.024
HDRS
• FIQ	0.789^*	0.001

MPQ T PRI: McGill pain questionnaire – total pain rating index, MPQ PPI-VAS: McGill pain questionnaire present pain intensity-visual analogue scale, HRSD: Hamilton Rating Scale for Depression, FIQ: fibromyalgia impact questionnaire.

* p is significant at 0.05 or less.

Table 5 Correlation between autonomic signs and different questionnaires.

Parameters	r	p
Supine systolic BP
• MPQ overall pain intensity	0.406^*	0.044
• HDRS	0.422^*	0.036
Standing systolic BP
• VAS falling sleep	0.413^*	0.040
Standing diastolic BP
• HDRS	0.429^*	0.032

BP: blood pressure, MPQ: McGill pain questionnaire, VAS: visual analogue scale, HRSD: Hamilton Rating Scale for Depression.

* p is significant at 0.05 or less.