Predictors of post-infectious chronic fatigue syndrome in adolescents

Figures & data

Figure 1. Flow sheet of youth with IM.

Table 1. Sociodemographic characteristics of the CFS and control groups.

	CFS (N = 39)	Control (N = 50)
Sociodemographic variables	M (SD)	M (SD)
Age	16.08 (1.40)	16.10 (1.50)
	N (%)	N (%)
Gender
Male	4 (10.3%)	13 (26.0%)
Female	35 (89.7%)	37 (74.0%)
Ethnic group
Caucasian	34 (87.2%)	47 (94.0%)
African-American	3 (7.7%)	1 (2.0%)
Latino	0 (0.0%)	1 (2.0%)
Other	2 (5.1%)	1 (2.0%)
SES^a
Unskilled laborers	1 (2.6%)	1 (2.0%)
Machine operators	9 (23.1%)	7 (14.0%)
Skilled craftsmen	13 (33.3%)	20 (40.0%)
Minor professional	9 (23.1%)	12 (24.0%)
Professional	5 (12.8%)	6 (12.0%)

^aBased on the parents' occupation.

Table 2. Simple logistic regression results predicting diagnosis.

	Without controlling for ASC					Controlling for ASC
Predictor baseline variables	b	SE	Wald χ^2	p-Value	OR	b	SE	Wald χ^2	p-Value	OR
Autonomic symptoms
ASC	.14	.03	22.23	.00	1.15
Perceived stress
Perceived stress score	.10	.03	9.81	.00	1.10	.06	.04	2.35	.12	1.06
Life events
Life events score	.60	.17	13.14	.00	1.83	.34	.20	2.89	.09	1.41
Family stress
Any family stress around or prior to mono onset?	.00	.00	2.79	.09	1.00	.00	.00	2.08	.15	1.00
If yes, is it still continuing?	.00	.00	1.68	.19	1.00	.00	.00	.34	.56	1.00
Since mono, has there been stress in your family?	.00	.00	2.73	.10	1.00	.00	.00	2.06	.15	1.00
If yes, is it still continuing?	.00	.00	3.18	.07	1.00	.00	.00	.51	.47	1.00
Difficulty functioning/attending school
Since mono, how many days have you spent in bed?	.08	.03	5.98	.01	1.08	.10	.05	4.85	.03	1.11
Since mono, how many days of school have you missed?	.09	.04	5.89	.01	1.09	.08	.05	2.68	.10	1.09
Hard time attending school regularly?	.00	.00	.03	.86	1.00	.00	.00	2.04	.15	1.00
Difficulties with concentrating, learning or remembering?	.63	.43	2.07	.15	1.87	.48	.54	.80	.37	1.62
Psychiatric diagnosis
Did participant receive at least one current diagnosis	1.39	.45	9.28	.00	4.00	.95	.55	2.98	.08	2.60
Total number of current diagnoses received	.68	.30	5.13	.02	1.97	.34	.34	.97	.32	1.41

Table 3. Likelihood-ratio-based forward selection step-wise logistic regression predicting diagnosis.

Step	Variables	b	SE	Wald χ^2	p-Value	OR
Step 1
	ASC	.18	.04	18.93	.00	1.20
Step 2
	ASC	.21	.05	17.58	.00	1.24
	Any family stress around or prior to mono onset?	.00	.00	0.05	.82	1.00
Step 3
	ASC	.25	.07	14.56	.00	1.29
	Any family stress around or prior to mono onset?	.00	.00	0.11	.74	1.00
	Since mono, how many days have you spent in bed	.14	.07	3.89	.05	1.15

Note: −2 Log likelihood for step 1 was 58.50, χ²(1) = 34.85, p = .00, for step 2, Δχ²(1) = 10.96, p = .00, for step 3, Δχ²(1) = 6.73, p = .01.