Genetic and environmental contributions to co-occurring physical health conditions in autism spectrum condition and attention-deficit/hyperactivity disorder

Table 1 Prevalence of autism/ADHD and physical health conditions in the total sample and subsamples by sex/zygosity

Full sample (N)	Total		MZF		DZF		MZM		DZM		DZOS		Unknown		Sample for twin model analysis^a
	32,250		4,934		5,184		4,600		5,976		11,010		546		20,694
	N	%	N	%	N	%	N	%	N	%	N	%	N	%	%	95% CI
Clinical autism	534	1.7	33	0.7	60	1.2	85	1.8	151	2.5	189	1.7	16	2.9	1.6	1.4, 1.8
Subclinical autism	1,251	3.9	96	1.9	157	3.0	211	4.6	328	5.5	434	3.9	25	4.6	4.0	3.7, 4.3
Clinical ADHD	1,427	4.4	117	2.4	169	3.3	240	5.2	369	6.2	501	4.6	31	5.7	4.3	4.0, 4.7
Subclinical ADHD	3,607	11.2	340	6.9	490	9.5	602	13.1	886	14.8	1,214	11.0	75	13.7	11.3	10.9, 11.8
Neurological disorders
Epilepsy	392	1.2	57	1.2	56	1.1	51	1.1	92	1.5	128	1.2	8	1.5	1.2	1.1, 1.4
Migraine	522	1.6	81	1.6	106	2.0	58	1.3	102	1.7	171	1.6	4	0.7	1.7	1.5, 1.9
Other headache	267	0.8	55	1.1	50	1.0	26	0.6	33	0.6	100	0.9	3	0.5	0.8	0.7, 0.9
Mixed headache	730	2.3	126	2.6	144	2.8	80	1.7	127	2.1	247	2.2	6	1.1	2.3	2.1, 2.5
Immunological disorders
Allergic rhinitis	1,920	6.0	244	4.9	234	4.5	301	6.5	445	7.4	670	6.1	26	4.8	5.9	5.6, 6.3
Asthma	4,317	13.4	514	10.4	695	13.4	598	13.0	960	16.1	1,476	13.4	74	13.6	13.4	12.8, 13.9
Atopic dermatitis	1,647	5.1	242	4.9	261	5.0	205	4.5	341	5.7	565	5.1	33	6.0	5.1	4.7, 5.4
Specific allergy	643	2.0	90	1.8	83	1.6	107	2.3	122	2.0	234	2.1	7	1.3	1.9	1.7, 2.2
Coeliac disease	362	1.1	72	1.5	73	1.4	29	0.6	52	0.9	131	1.2	5	0.9	1.1	0.9, 1.3
Gastrointestinal disorders
Constipation	2,035	6.3	271	5.5	345	6.7	258	5.6	400	6.7	728	6.7	33	6.0	6.2	5.8, 6.5
Functional diarrhea	187	0.6	31	0.6	35	0.7	24	0.5	39	0.7	54	0.5	4	0.7	0.6	0.5, 0.7
Irritable bowel syndrome	127	0.4	30	0.6	25	0.5	7	0.2	11	0.2	53	0.5	1	0.2	0.4	0.3, 0.4
Mixed FGIDs	2,283	7.1	320	6.5	390	7.5	283	6.2	431	7.2	821	7.5	38	7.0	6.9	6.5, 7.3

The physical health conditions in this study did not include the data from primary care health services
ADHD, attention-deficit/hyperactivity disorder; DZF, dizygotic female; DZM, dizygotic male; DZOS, dizygotic opposite sex; FGIDs, functional gastrointestinal disorders; MZF, monozygotic female; MZM, monozygotic male
^aMZ and same-sex DZ twins

ISSN: 2040-2392