JSNA Review of Autism in Essex

Transcription

1 JSNA Review of Autism in Essex Executive Summary: 1. The estimates presented here are approximate and based on prevalence rates of autism in the population published nationally (UK) and applied to latest population estimates in Essex. There are no precise headcounts of local diagnosis of prevalence. 2. Essex County Council s Adult Autism Strategy was published in July The appendix from the Strategy: Data and Evidence is re-presented here for information. This includes data on the number of children with a SEN (Special Education Needs) statement indicating autism. 3. The diagnosis of people with autism, described as a spectrum remains controversial. There is an international debate currently on-going about a need to re-classify autism from a diagnosis of deficit to one of ability in socialisation. The discussion and proposal, known as DSM-5 (Diagnostic and Statistical Manual) is presented in section Finally there is a summary on the latest Literature Review of autism research and prevalence across different countries. 1. Introduction Autism Spectrum Disorders (ASD) are developmental disabilities characterized by difficulties with social interactions, impairment in verbal and/or nonverbal communication, and the development of repetitive or highly-specialized interests. The pathology underlying the condition is based in the brain, although the precise disease mechanism behind ASD is not conclusive. ASDs are typically diagnosed in early childhood with functional impairment persisting throughout life. The main symptoms of ASD are particular social and language problems. Often, but not always, children with ASDs will have delays developing spoken language. The specialized interests that develop in persons with ASD can be quite varied. In young children this can first appear as constant lining up of, rather than playing with, toys or obsessive watching and re-watching of segments of a particular video/dvd. Older, verbal children with ASD may show a strong tendency to talk, regardless of the setting or context, about particular topics of interest. There is no physiological test that can diagnose ASD. There are no definitive biologic signs or symptoms of ASD and it is diagnosed only based on careful observation/assessment of behaviour and knowledge of the individual s developmental history. Much of the rapid increase in cases of ASD may be due to better diagnosis, wider awareness and broader definitions of autism. Autism used to be diagnosed only in children with severe language and social problems and repetitive behaviors, but researchers have expanded the criteria for diagnosis to also include a wider spectrum of developmental conditions. These include Asperger Syndrome, Pervasive Developmental Disability Not Otherwise Specified (PDD-NOS), Rett s Syndrome, and Childhood Disintegrative Disorder.

2 2. Prevalence Studies: There is broad consensus among research papers on ASD that the overall prevalence of autism in the UK population is around 1%. Due to the spectrum nature of the condition, larger estimates of unknown (or undiagnosed) rates are also published by studies. Variations in prevalence are also reported across gender, race, social class, rural/urban populations and across countries by research studies over the past decade. There are also reports of an increasing prevalence over time, although it is not conclusive - if this is a real trend, or due to increased awareness and better diagnosis. 3. Estimates of autism in children and adult: To establish an approximate number of people with autism in Essex, three recent UK studies have been used to calculate the overall numbers. 1. Prevalence of disorders of the autism spectrum in a population cohort of children in South Thames: the Special Needs and Autism Project (SNAP) The Lancet, Volume 368, Issue 9531, July 2006, Pages Gillian Baird, FRCPCH, Emily Simonoff, MD, Andrew Pickles, PhD, Susie Chandler, PhD, Tom Loucas, PhD, David Meldrum, FRACP, Tony Charman, PhD Findings: The prevalence of childhood autism was 38 9 per (95% CI ) and that of other ASDs was 77 2 per ( ), making the total prevalence of all ASDs per ( ). A narrower definition of childhood autism, which combined clinical consensus with instrument criteria for past and current presentation, provided a prevalence of 24 8 per ( ). 2. Prevalence of autism-spectrum conditions: UK school-based population study The British Journal of Psychiatry (2009) 194: doi: /bjp.bp Simon Baron Cohen, University of Cambridge, Autism Research Centre, Department of Psychiatry, Douglas House, 18b Trumpington Road, Cambridge CB2 8AH, UK. sb205@cam.ac.uk Results The prevalence estimates generated from the SEN register and diagnosis survey were 94 per and 99 per respectively. The ratio of known:unknown cases is about 3:2 (following statistical weighting procedures). Taken together, we estimate the prevalence to be 157 per , including previously undiagnosed cases.

3 Among children, the overall rate of per 10,000 population for the Baird et al study, and 94 or 99 per 10,000 population for the Baron-Cohen et al. study are broadly in line with a 1% prevalence among children. Among adults, a study by Brugha et.al. for the NHS Information Centre also reveals a 1% overall population, however, a much higher prevalence (of 1.8%) for males than female (at 0.2%) see table 1A. This study did not find any significant differences in autism when split into broad age groups to be fairly consistent at 1% across all ages, with a slightly higher rate for younger age groups see Table 1B. 3. Autism Spectrum Disorders in adults living in households throughout England Report from the Adult Psychiatric Morbidity Survey 2007 Published by The NHS Information Centre for health and social care. This publication is available on the Internet at Brugha T, McManus S, Meltzer H, Smith J, Scott FJ, Purdon S, Harris J, Bankart J

4 4. Extract from Adult Autism Strategy (July 2013) Essex County Council: Autism in Essex data and evidence Existing database systems do not give us accurate or consistent figures for numbers of people with autism in Essex or within our services. The prevalence of autism within the adult population is estimated to be 1% of the adult population in England, with the rate among men (1.8%) higher than that among women (0.2%) 1 (Health & Social Care Information Centre). Based on this, the number of people in Essex who are likely to have autism is set out below: Population aged predicted to have autistic spectrum disorder Essex: Total population 8,411 8,735 9,154 Colchester Chelmsford Basildon Braintree Tendring Epping Forest Castle Point Harlow Rochford Uttlesford Brentwood Maldon 1,145 1,033 1, ,238 1,053 1, ,336 1,090 1, Within the autism population, 45% are estimated to be high functioning ie they have an IQ above This will include many with Asperger s Syndrome. Population aged estimated to have high functioning autism Essex: Total population Colchester Chelmsford Basildon Braintree Tendring Epping Forest Castle Point Harlow Rochford Uttlesford Brentwood Maldon Health & Social Care Information Centre 2 Source: v6.0; accessed November Baird et al (2006) as cited in Knapp, The Economic Consequences of Autism in the UK (2007); 4 Source: calculated from adult autism population estimates obtained from PANSI.

5 Where adults with autism qualify for support from social care, they are most likely to be supported within learning disability services. However the presence of autism is not normally recorded on our database. Research has found that within the adult learning disabled population, the likely prevalence of autism is between 20% and 30% - and within specialised learning disability services is more likely to lie at the upper end of that range 5. People with moderate to severe learning disabilities in Essex 6 The number of people aged 18+ predicted to have moderate to severe learning disabilities 2013 Total likely to have autism (30%) Total known to adult social care (LD 18+) Essex Colchester Basildon Chelmsford Tendring Braintree Epping Forest Castle Point Rochford Harlow Uttlesford Brentwood Maldon Emerson, Baines The estimated prevalence of autism among adults with learning disabilities in England (IHAL / LDO, 2010) 6 Sources: Total Population PANSI; Autism estimated according to Emerson, Baines prevalence estimate (higher range); Total known to social care Essex County Council (Feb 2012).

6 People with learning disability known to adult social care services in Essex by age plus likely prevalence of autism 7 Colchester Tendring Braintree Basildon Total Aged Aged Aged Aged 65+ LD Autism est. LD Autism est. LD Autism est. LD Autism est. LD Autism est. Essex Chelmsford Epping Forest Castle Point Brentwood Harlow Rochford Maldon Uttlesford Source: Essex County Council (Feb 2012); Autism prevalence calculated in line with Emerson, Baines at upper level (30%)

7 This strategy is concerned with adults. However Schools, Children & Families have more extensive information about children and young people with autism in their special educational needs database. It is worth looking at this, particularly as these are not dependent on estimates of prevalence. Young people with severe or complex needs may be more likely to require adult services in adulthood. Numbers of children with a statement of special educational needs with autism as the main category of need (January 2013) 8 Total Essex 885 Mid 260 North East 253 South 229 West 143 Tendring 136 Basildon 118 Colchester 117 Chelmsford 116 Braintree 112 Epping Forest 68 Brentwood 48 Uttlesford 42 Harlow 33 Castle Point 32 Maldon 32 Rochford 31 8 Source: School Census (PLASC), January 2013

8 Autism and mental health People with autism have been shown to be more prone to mental health problems although research differs on whether they are more vulnerable than people with learning disability and no study has established definitive prevalence rates in adults with autism. Affective disorders such as depression and anxiety are the most common psychiatric disorders. Rates of depression and anxiety have also been found to be higher among close relatives of people with autism. A systematic review of follow-up studies from childhood to adulthood (Howlin, 2000) concluded that depression, often associated with severe anxiety is the most common psychiatric disorder in adults with high functioning autism. 9 There are significant overlaps between the presentation of adults with autism, particularly high functioning autism, and the presentation of adults with psychosis. Similarities between symptoms can complicate the picture and lead to misdiagnosis. This means it is possible that some long term users of mental health services who have been diagnosed with psychosis might be more appropriately supported in the context of a diagnosis of Asperger s Syndrome. 10 A recent study in North Wales for the Welsh Assembly Government estimated that 1.4% of cases open to Adult Mental Health services are likely to have autism and almost half of these will not be formally diagnosed. Furthermore the probability of receiving a service from Adult Mental Health is approximately five times greater for adults with autism than in the normal population. The study suggested that this is likely to be an under-estimate of the true prevalence of autism within the AMH caseload for a number of reasons including lack of diagnosis and poor recognition Tsakanikos et al Psychopathology in adults with autism and intellectual disability (2005) 10 Jackson et al Mental health services for adults with autism spectrum disorders in North Wales (2011) summarising evidence on autism and mental health. 11 Jackson et al (2011)

9 Economic consequences of autism Research carried out for the Foundation for People with Learning Disabilities in 2007 on the economic consequences of autism in the UK 12 estimated that the average annual costs for adults with an ASD and a learning disability range from 36,507 to 97,863. It was estimated that average annual costs for adults with a high functioning ASD range from 32,681 to 87,299. These estimates include about 59% service costs 13 with the remainder accounted for by lost employment (for both the person and their family) and family expenses. The same research estimated that 79% of adults with high functioning autism live in private residences with parents or relatives; 5% live in Supporting People accommodation; 16% in residential care and none in hospital. Adults with autism and a learning disability were less likely to live in their own home the research estimated that 31% live in private residences; 2% in their own home; 2% in a private home with a partner; 7% in Supporting People accommodation; 52% in residential care and 6% in hospital. For an adult with high functioning autism the annual cost of living in a private household (with or without family) was estimated to be 32,681, of which almost 20,000 was attributable to the cost of lost employment for the individual. Costs for high functioning adults in supported living settings or care homes were estimated to be much higher ( 84,703 and 87,299 respectively) and a much higher proportion of this was attributable to the cost of accommodation and support staff. For adults with autism and a learning disability, the mean annual costs excluding benefits but including lost employment were calculated to be 36,507 for those living in private households; 87,652 for those living in Supporting People settings; 88,937 for those living in residential care and 97,863 for those living long term in hospital. For people living in private households, the largest service cost elements are associated with day care, respite services and adult education. For people in Supporting People settings and residential care, the accommodation itself is the largest cost element. 12 Martin Knapp et al The Economic Consequences of Autism in the UK (Foundation for People with Learning Disabilities, 2007). 13 The research took into account health, social care, education, housing and leisure costs but only where they related to an individual s autism.

10 5. Some current discussion around classification of autism: There are currently debate among professionals and communities affected by ASD on how to classify the type and degree of autism within the spectrum. As recently as 18 May 2013, The American Psychiatric Association (APA) has revised its diagnostic manual, known as the Diagnostic and Statistical Manual (DSM-5). This updates the DSM-IV Classification which is more in line with current classification in the UK. Although the DSM is influential, the main set of criteria used in the UK is the World Health Organisation s International Classification of Diseases (ICD), so there will be no immediate changes to the way that autism and Asperger syndrome are diagnosed in this country. The ICD will be updated in The main difference between DSM-IV and DSM-5 is the move away from a purely clinical-model approach to diagnosis (for example, by behaviour traits) to a more social-model approach, on the ability to function, thus assessing individuals by: 1. Deficits in social-emotional reciprocity 2. Deficits in nonverbal communicative behaviors used for social interaction 3. Deficits in developing, maintaining, and understanding relationships." So while DSM-5 s attempt to re-classify degrees of autism by degrees of function, this is controversial as the criteria is seen by some as imperfect (there are overlaps) and it cuts through traditional understanding of the difference between, say High Functioning Autism and Asperger Syndrome. For more discussion on the reclassification of ASD: AS-diagnostic-criteria.aspx

11 6. Literature Review: The following literature review gives a summary of research on prevalence and epidemiology from across the world. a) Research Countries: The predominant countries looking into the prevalence of ASD is the USA 1,3,10,11,13,15,16,17,21,30, 32, 34, 35,36 4,6,8,18,24,33,37,38, 39,40,41. and the UK The review also includes papers from Japan 2,5 Serbia 7 France 9 Denmark Taiwan 19, The Netherlands 20 South Korea 23,29, Australia 28 and a collection of International collaborative studies 14,22,27 12,28, 31 b) Prevalence: Increase in prevalence 1,2,3,10,16,17 cannot just be due to better diagnosis alone 7. Environmental effect is a suggested cause 23 in research with concordant twins and siblings 1,10, 12, 31 Prevalence of ASD varies quite dramatically from study to study (dependent on definitions, sampling, age, etc.) however, prevalence at 1% (or close to 1%) 7,12,33,37,38,39 of the population is confirmed by several independent studies. A UK based study 40 looked across research papers on prevalence and concluded that large variations in rates (61%) can be explained by diagnostics and/or measurement methods. However, it is interesting to note that an American study 36 based on Special Education Data found that areas with the highest prevalence seem to be levelling-off while areas with lower prevalence are still catching up. In terms of undiagnosed cases, a South Korean study 29 suggest that the figure could be as high as two out of three cases of ASD remain undiagnosed, while the rate in a UK study 38 suggests a lower rate of two out of every five cases. i. Prevalence by Sex: Generally, prevalence is found to be higher in boys / males 17,19,22,23,26,27,33,35, however an American research found severity is greater in girls / women 10, although another study suggested perhaps better compensation displayed by girls with lower severity or less RSB (repetitive stereotyped behaviour) 21,22. ii. Prevalence by Ethnicity: In terms of variations between ethnic groups, a study in American found prevalence highest in the White ethnic group, and lowest in Hispanic 11, 35 although another study suggested this could be due to better 12 awareness and access to pediatric developmental services among the White population in its study 13. iii. Prevalence by Social Class: A conclusion by an international collaborative study 14 suggested lower prevalence found in middle and lower income communities/countries is likely to be correlated to lower awareness of ASD. To test this hypothesis, a Swedish study 25 confirmed that when properly measured (in a universal healthcare system widely available and accessed in Sweden) they found the opposite to be true: more accurate measures across the entire population found higher prevalence in lower Socio Economic Status (SES) group and manual occupations. An ASD diagnosis was found to be more prevalent in lower SES after accounting for factors such as parental education, parental ages, migration status and maternal smoking during pregnancy. It concluded that studies which found greater prevalence in higher SES may be underestimating the burden in lower income groups. A UK based study 33 found prevalence higher among men without educational qualification and those living in rented social housing, although it did not propose possible cause or effect.

12 c) Co-morbidity with ASD: A diagnosis of ASD is often found with other conditions such as Learning Disability and psychotic illness 4, Allergy 5, Downs Syndrome 6. For example, children with ASD and Down Syndrome display significant behavioural problems than other DS children who show no significant autism symptoms. A French studied the linked between ASD and Epilepsy 9 while a UK study looked at babies born extremely preterm (not more than 26 weeks gestational age) who screened positive for ASD and with sensory (hearing and/or visual) impairment 24. An American study 35 concluded that the comorbidity could be masking a higher rate of un-diagnosed prevalence of ASD. While the debate about measuring morbidity continues, there is research that supports the new DSM-V reclassification 7 which is based on an individual s abilities to be independent rather than a measure of their conditions of debility. d) Geographic distribution: A UK study found higher prevalence in rural area although findings are not conclusive and at odds with other research 8. A French study 9 of two separate areas on standard age and diagnostic measures show remarkably similar results while a Dutch study 20 found large variations between areas within The Netherlands and suggested that areas with high prevalent of information-technology use could be a factor. Comparative studies at rates between countries show huge variations 28. e) Foetal development: A UK study proposed that mental health problems of the child s mother could be a variable factor 15 while a US study found a doubling of ASD prevalence with older mothers (40+) 26 A biological review of ASD by an international team suggests the Extreme Male Brain (EMB) as the typical systemizing male brain developed as an effect of higher levels of foetal testosterone (ft) 27. An American study 34 looked at possible relationships between perinatal risk factors such as preterm, very preterm, low and very low birth-weight, multiple-births, caesarean delivery, breech presentation and IVF. Although various pregnancy factors have been found to be associated with ASDs, the contribution of many of these factors to the recently observed ASD increase is likely to be minimal. f) Vaccination: An American study found a positive and statistically significant relationship between autism and childhood vaccination uptake across the US population. The study controlled for two variables only: family income and ethnicity and found that a 1% increase in vaccination was associated with an additional 680 children having autism or SLI (Speech/Language Impairment). However, conclusions of the study included caveats that the research is based on statistical association and suggested mercury, now removed from vaccination, or other culprits could be the cause 32. In the UK, a study 41 in parental perception regarding the onset or cause of autism showed a clear trigger date of August 1997 when the MMR (measles, mumps and rubella) vaccine was more likely to be cited as a cause. g) Recommendations: Not all research studies offered recommendations. However, some that did include: early diagnosis and treatment is shown to be effective 1 longitudinal studies to be conducted to determine if increasing prevalence is real or due to increased awareness, different definitions and measurements 2

13 more specific targeting needed in communities with lower awareness of ASD symptoms 15 medication management and better training of professionals produce effective outcomes 3 there are benefits of focussing attention on youths with an ASD to ensure continuity of care as they leave school 30.