Heart rate and heart rate variability in patients with chronic inflammatory joint disease: the role of pain duration and the insular cortex

Table 1 Characteristics of participants

	Controls	CIJD	p
Sample size, n	22	22
Gender (m/f)	6/16	6/16
Age (years), mean (SD)	50.9 (±10.6)	51.3 (±10.2)	0.896
Smoking (yes/no/earlier)	17/2/3	14/3/5	0.609
Education^a (median)	3	2	0.550
Chronic inflammatory joint diseases:
Rheumatoid arthritis; n	n.a.	9	n.a.
Ankylosing spondylitis; n	n.a.	9	n.a.
Psoriatic arthropathy; n	n.a.	3	n.a.
CREST syndrome^b; n	n.a.	1	n.a.
Pain duration (years), median (min./max.)	n.a.	10 (1/44)	n.a.
Pain intensity, median (min./max.)^c	n.a.	3.5 (0/7)	n.a.

^aThe level of education was classified according to the achieved academic degree: 0 = no degree, 1 = secondary school, 2 = middle school, 3 = High school diploma, 4 = university/ college
^bCREST Calcinosis, Raynaud’s phenomenon, esophageal motility abnormalities, sclerodactyly and telangiectasia
^c11-NRS 11-point numerical rating scale (0 = no pain to 10 = worst pain imaginable), on the day of testing under usual medication
SD Standard deviation, CIJD patients with chronic inflammatory joint diseases, n.a. Not applicable

ISSN: 1471-2474