In search of risk factors for chronic pain in adolescents: a case–control study of childhood and parental associations

Figures & data

Table 1 Individual history of prior FPS: total number of FPS reported by cases and controls

	Cases (N = 45)	Controls (N = 56)
	N (%)	N (%)
Reporting no FPS	13 (28.9)	45 (80.4)
Reporting 1 FPS	17 (37.8)	6 (10.7)
Reporting 2 FPS	5 (11.1)	4 (7.1)
Reporting 3 FPS	8 (17.8)	1 (1.8)
Reporting 4 FPS	2 (4.4)	0 (0)

Abbreviation: FPS, functional pain syndromes.

Table 2 Individual history of prior FPS: specific FPS reported by cases and controls

	Cases (N = 45)	Controls (N = 56)	P-value	OR	95% CI
	N (%)	N (%)
GP	8 (17.8)	4 (7.1)	0.18	2.8	0.8–10.0
Migraine	10 (22.2)	2 (3.6)	0.01	7.7	1.6–37.3
Non-migraine headaches	13 (28.9)	1 (1.8)	<0.001	22.3	2.8–178.9
RAP	11 (24.4)	3 (5.4)	0.01	5.7	1.5–22.0
RLS	10 (22.2)	3 (5.4)	0.03	5.1	1.3–19.7
Other	7 (14.9)	4 (7.1)	0.34	2.28	0.6–8.3

Abbreviations: CI, confidence interval; FPS, functional pain syndromes; GP, growing pains; OR, odds ratio; RAP, recurrent abdominal pain; RLS, restless legs syndrome.

Table 3 Parental history of functional pain syndromes

	Cases (N = 45)	Controls (N = 56)	P-value	OR	95% CI
	N (%)	N (%)
GP	7 (15.6)	5 (8.9)	0.48	1.9	0.6–6.4
Migraine	23 (51.1)	15 (27.3)	0.03	2.8	1.2–6.4
Non-migraine headaches	9 (20.0)	10 (18.2)	1.00	1.1	0.4–3.1
RAP	18 (40.0)	6 (10.9)	0.00	5.4	1.9–15.4
RLS	12 (26.7)	4 (7.3)	0.02	4.6	1.4–15.6
Fibromyalgia	1 (2.2)	2 (3.6)	1.00†	0.6	0.1–6.9
Other	7 (15.6)	7 (12.7)	0.91	1.3	0.4–3.9

Note:

† Fisher’s exact test.

Abbreviations: CI, confidence interval; GP, growing pains; OR, odds ratio; RAP, recurrent abdominal pain; RLS, restless legs syndrome.

Table 4 Associations in (early) childhood with chronic pain in adolescents

	Cases (N = 45)	Controls (N = 56)	P-value	OR	95% CI
	N (%)	N (%)
Academic level (below average)	15 (33.3)	8 (14.3)	0.04	3.0	1.1–7.9
Birth weight (low [<2.5 grams])	4 (9.1)	3 (6.4)	0.71†	1.5	0.3–7.0
Prematurity	6 (13.3)	4 (7.1)	0.33†	2.0	0.5–7.6
Hospitalization	23 (52.3)	22 (39.3)	0.27	1.7	0.8–3.8
Serious injury	10 (22.2)	3 (5.4)	0.03	5.1	1.3–19.7
Adversity	21 (46.7)	13 (23.2)	0.02	2.9	1.2–6.8
Acute pain	24 (53.3)	26 (46.4)	0.62	1.3	0.6–2.9
Living away from home	5 (11.1)	5 (8.9)	0.75†	1.3	0.4–4.7
Use of medication	28 (66.7)	5 (9.8)	<0.001	18.4	6.0–56.6
Using the computer (>2.5 hours a day)	13 (31.0)	11 (21.2)	0.40	1.7	0.7–4.3
Watching TV (>2.5 hours a week)	9 (21.4)	3 (5.8)	0.05	4.5	1.1–17.7
Playing instrument (>5 hours a week)	2 (4.8)	7 (13.5)	0.18†	0.3	0.1–1.6
Prolonged fatigue	20 (44.4)	6 (10.7)	<0.001	6.7	2.4–18.7
Low iron	11 (24.4)	4 (7.3)	0.04	4.1	1.2–14.0
Low vitamin D	6 (13.3)	1 (1.8)	0.04†	8.3	1.0–71.8
Hypermobility	3 (7.1)	4 (7.7)	1.00†	0.9	0.2–4.4
Physical exercise (>2.5 hours a week)	26 (61.9)	38 (73.1)	0.35	0.6	0.3–1.4

Note:

† Fisher’s exact test.

Abbreviations: CI, confidence interval; OR, odds ratio.

Table 5 Variables in the multivariate model for statistical prediction of chronic pain in adolescents

	P-value	OR	95% CI
Individual history of
Migraine	0.03	7.8	1.3–48.4
Non-migraine headaches	0.01	18.3	2.0–170.0
RAP	0.01	8.2	1.7–40.0
Parental history of
RAP	0.02	5.1	1.4–18.8
Depression	0.02	4.4	1.3–14.9

Abbreviations: CI, confidence interval; OR, odds ratio; RAP, recurrent abdominal pain.