Subsequent psychiatric disorders in attention deficit and hyperactivity children receiving speech therapy

Table 3 Incidences and hazard ratios of subsequent psychiatric disorders between attention deficit and hyperactivity disorder patients who received speech and language therapy (speech and language therapy cohort) and propensity matched comparison subjects who did not receive speech therapy (non-speech and language therapy cohort as reference group); also stratified by sex, age, and comorbidity

Variable	ADHD children						Adjusted hazard ratio (95%CI)
	Non-ST cohort			ST cohort
	Event	PY	Rate	Event	PY	Rate
Any disorder	701	21677	32.34	531	24622	21.57	0.72 (0.63-0.82)c
Affective disorder	64	32725	1.96	51	32681	1.56	0.76 (0.51-1.14)
Schizophrenia	21	33393	0.63	10	33314	0.30	0.43 (0.17-1.12)
Psychosis	13	33598	0.39	20	33088	0.60	1.63 (0.67-3.92)
Conduct disorders	3	33794	0.09	4	33467	0.12	1.33 (0.30-5.60)
Impulsive disorder	13	33651	0.39	8	33402	0.24	0.64 (0.25-1.64)
Oppositional defiant disorder	76	32600	2.33	60	32600	1.84	0.80 (0.56-1.15)
Emotional disturbances	249	29734	8.37	207	30201	6.85	0.81 (0.67-0.99)a
Personality disorders	3	33764	0.09	4	33442	0.12	1.00 (0.14-7.10)
Anxiety disorders	420	26354	15.94	318	28002	11.36	0.73 (0.67-0.86)c
Adjustment disorder	112	31467	3.56	66	32256	2.05	0.52 (0.36-0.73)c
Sex
Girls	124	4121	30.09	88	5095	17.27	0.70 (0.52-0.96)a
Boys	577	17247	33.45	443	18516	23.93	0.72 (0.63-0.83)c
Age at ADHD diagnosis, years
< 4	112	4934	22.70	94	5287	17.78	1.50 (0.80-2.82)
> 4	589	16561	35.57	437	18437	23.70	0.73 (0.62-0.85)c
Any comorbidities
No	124	4864	25.49	85	4754	17.88	0.70 (0.50-0.99)a
Yes	577	15962	36.15	446	19491	22.88	0.73 (0.63-0.84)c

^aP < 0.05.

^cP < 0.001.

Study and comparison subjects were matched by propensity scores. Rate represents incidence rate (per 1000 person-years). Multivariate Cox model controlled for age, gender, comorbidities, behavioral interventions, and drug used. Any comorbidities included cerebral palsy, autism, hearing loss, delay development, or mental retardation. ADHD: Attention deficit and hyperactivity disorder; ST: Speech and language therapy; PY: Person-years; 95%CI: 95% confidence interval.