Table 1 Summary of studies published between 2000–2011 exploring psychiatric comorbidity in asperger syndrome and high functioning autism

DEPRESSION

Green et al., 2000 [6]

Comparison between AS and CD.

20 AS (13.75) Range: 11-19

20 CD (14.47) Range: 11-19

ICD-10

Asperger showed higher rates of depression than controls. Chronic unhappiness and loneliness were more commonly associated with AS.

Kim et al., 2000 [7]

Follow-up to clinic series.

19 AS 40 HFARange: 9-14

1751 CG Range: 9-14

OCHS-R

17% had clinically relevant depression scores. Depression correlated with anxiousness and externalizing behavior.

Barnhill, 2001 [8]

Descriptive study of depressive symptoms.

33 AS Range: 12-17

None

CDI

54% reported depressive symptoms, with a significant positive relationship between depression symptoms and ability attribution for social failure.

Hedley et al., 2006 [9]

Relationship between social comparison processes and depressive symptoms.

36 AS (12.9 ± 1.94) Range: 10-16

None

SCS CDI

Participants who perceived themselves as being more dissimal to others reported higher depressive symptoms.

Meyer et al., 2006 [10]

Cross-selectional study about depression in AS.

31 AS (10.1 ± 1.9)

33 CG (10.2 ± 1.9)

BASC-SRP BASC-PRS

The children themselves reported greater symptoms of anxiety and depression.

Whitehouse et al., 2009 [11]

Relationship between loneliness and depressive symptoms in AS

35 AS (14.2 ± 0.8)

35 CG (14.4 ± 0.10)

CES-DC

Around two thirds (n = 23) of the adolescent with AS self-reported significantly higher levels of depressive symptoms than control group.

Lugnegård et al., 2011 [12]

Evaluation of psychiatric comorbidity

54 AS (27.0 ± 3.9)

None

SCID

70% had experienced at least one episode of major depression, and 27 of these (50% of the total group) had recurrent major depressions.

BIPOLAR

Munesue et al., 2008 [13]

Study of mood disorders in consecutive outpatients.

44 HFA Range: 13-39

None

DSM-IV

Sixteen patients (36.4%) were diagnosed with mood disorder. Among these bipolar disorder accounted for 75% of cases.

Hofvander et al., 2009 [14]

Evaluation of psychiatric and psychosocial problems in ASD with normal IQ

5AD 67 AS 50 PDD-NOS Range: 16-60

None

DSM-IV

In the AS subgroup the most common life-time comorbid condition was mood disorder (n = 65, 53%). Criteria for a bipolar disorder (BP) were met by 10 subjects (8%), five of whom had bipolar I subtype and two bipolar II, while three were coded as unknown subtypes.

Lugnegård et al., 2011 [12]

Evaluation of psychiatric comorbidity

54 AS (27.0 ± 3.9)

None

SCID

Five participants (9% of total group) met criteria for bipolar II disorder, whereas none met criteria for bipolar I disorder.

ANXIETY

Green et al., 2000 [6]

Comparison between AS and CD.

20 AS(13.75) Range: 11-19

20 CD (14.47) Range: 11-19

ICD-10

Asperger showed more symptoms of general anxiety and OCD than CD

Gillott et al., 2001 [15]

Measures of anxiety and social worries.

15 HFA Range: 8-12

30 CG Range: 8-12

SCAS SWQ

HFA group showed higher rates of anxiety than in typically developing or language impaired children. 7 of 15 children with HFA were at or above clinical mean score.

Burnette et al., 2005 [16]

Relations between the weak central coherence hypothesis, theory of mind skills, and social-emotional functioning.

23 HFA (11. 25 ± 1.57)

20 CG (11.00 ± 1.32)

BASC-SRP SASC-R

Autistic subjects self-reported significantly more social anxiety symptoms

Pfeiffer et al., 2005 [17]

Relationships between sensory modulation and symptoms of affective disorders.

50 AS Range: 6-17

None

MASC

Significant correlation was found between sensory defensiveness and anxiety in children with AS

Russell and Sofronoff, 2005 [18]

Examination of anxiety and social worries in AS.

65 AS Range: 10-13

261 CG Range: 10-13

SCAS SWQ

AS self-reported levels of anxiety symptoms significantly higher than control group

Meyer et al., 2006 [10]

Cross-selectional study about anxiety in AS.

31 AS (10.1 ± 1.9)

33 CG (10.2 ± 1.9)

BASC-SRP BASC-PRS

AS self-reported high social anxiety levels correlating with their social perception, understanding and experience.

Sukhodolsky et al., 2008 [19]

Study of the frequency of anxiety symptoms in PDD.

171 ASD (8.2 ± 2.6)

None

CASI

73 (43%) had a pathological scores for at least one anxiety disorder. Higher levels of anxiety were associated with higher IQ, functional language use, and stereotyped behaviors.

Kuusikko et al., 2008 [20]

Association between AS/HFA and social anxiety symptoms.

54 HFA/AS (11.2 ± 2.2)

305 CG (12.2 ± 2.2)

SPAI-C SASC-R CBCL

Adolescents with HFA/AS suffered from more symptoms of social anxiety than the community sample on all measures.

Lugnegård et al., 2011 [12]

Evaluation of psychiatric comorbidity

54 AS (27.0 ± 3.9)

None

SCID

56% met criteria for at least one anxiety disorder, and 11 of these fulfilled diagnostic criteria for two or more anxiety disorder diagnoses. 22% had social anxiety disorder, 22% had generalized anxiety disorder, 13% had panic disorder, 15% had agoraphobia and 7% had OCD.

OCD

Russell et al., 2005 [21]

Study of Obsessive Repetitive behaviours in AS and OCD groups.

40 AS/HFA (27.9 ± 8.5)

45 OCD (36.6 ± 11.5)

Y-BOCS

The two groups had similar frequencies of obsessive-compulsive symptoms. Somatic obsession and repeating rituals were more common in the OCD group.

South et al., 2005 [22]

Study of the four repetitive behavior categories, comparing AS/HFA and CG.

19 AS (14.10±3.47), 21 HFA (14.28±3.02)

21 CG (13.34 ± 3.28)

RBI, YSII

The CG showed lower scores than AS/HFA for all four repetitive behavior categories: Object Use; Motor Movements; Rigid Routines and Circumscribed Interests.

Zandt et al., 2007 [23]

Study of the types of ripetitive behaviours in ASD.

19 ASD (10.97 ± 2.42)

17 OCD (12.30 ± 2.17), 18 TD (11.942.94)

RBQ, CY-BOCS

Children with ASD reported more compulsions and obsessions than typically developing children. Consideration of the type of compulsions and obsessions in each disorder suggests that the compulsions in ASD tended to be less sophisticated.

Ruta et al., 2009 [24]

Examination of the occurrence and characteristic features of obsessive–compulsive behaviours.

18 AS (10.61 ± 1.91)

20 OCD (11.65 ± 1.69), 22 TD (10.68 ± 2.01)

CY-BOCS

The AS group displayed slightly higher frequencies of Saving/Hoarding and Ordering clusters compared to OCD group.

Mack et al., 2010 [25]

Clinical characteristics and symptoms severity in patients with OCD + AS/HFA; OCD + TS or OCD alone.

12AS/HFA + OCD Range:12-18

12 OCD + TS Range: 9–17, 12 OCD Range: 9-17

Y-BOCS

Children with ASD may experience a similar level of impairment, equally distressing, time consuming and contributing to a similar level of interference in functioning from obsessive/compulsive symptoms as compared to children with TS plus OCD and children with OCD only.

Lai et al., 2011 [26]

Behavioral Comparison of Male and Female Adults with High Functioning Autism Disorders.

68 AS/HFA Range: 18-45

None

BAI, BDI, OCI-R

A significant proportion of adults with AS/HFA showed clinically significant anxiety, depression, or obsessive-compulsive symptoms. Overall male and female adults with ASC were not different on these symptoms.

ADHD

Holtman et al., 2005 [27]

Study of the frequency of ADHD-like symptoms in AS/HFA

104 AS/HFA Range: 3.4-20.2

None

CBCL

Sixty-five percent of the subjects scored above the clinical cut-off on the attention problems scale

Tani et al., 2006 [28]

Exploration of childhood ADHD problems retrospectively

20 AS (27.2 ± 7.3)

10 TD (26.5 ± 8.1)

WURS

AS group displayed higher scores as indicated from self- and parents-report.

Simonoff et al., 2008 [29]

Assessment of psychiatric disorders in ASD

112 ASD (11.5) Range: 10–13.9

None

DSM-IV

70.8% of ASD children had at least one current psychiatric disorder. The most common comorbidities were social anxiety (29.2%), ADHD (28.1%), and oppositional defiant disorder (28.1%).

Mattila et al., 2010 [30]

Community- and clinic-based study exploring comorbid psychiatry in AS/HFA

50 AS/HFA (12.7 ± 1.5)

None

K-SADS-PL CGAS

One or more comorbid psychiatric disorders were diagnosed in 74% of the cases. The most common disorders were behavioural (44%), anxiety (42%) and tic disorders (26%).

Mukaddes et al., 2010 [31]

Comparison the rate and type of psychiatric comorbidity in children and adolescents HFA/AS

30 AS, 30 HFA

None

K-SADS-PL

The rate of comorbid psychiatric disorders was very high in both groups. The most common disorder in both groups was attention deficit hyperactivity disorder. The AS group displayed greater comorbidity with depressive disorders and ADHD.