A study on prescriptions contributing to the risk of high anticholinergic burden in adults with intellectual disabilities: retrospective record linkage study.

BACKGROUND: People with intellectual disabilities may face a disproportionate risk of experiencing high anticholinergic burden, and its negative sequalae, from a range of medications, and at younger ages than the general population, but there has been little previous study. Our aim was to determine the source of anticholinergic burden from prescribed medication. METHODS: Retrospective matched observational study using record linkage. Adults with (n = 4,305), and without (n = 12,915), intellectual disabilities matched by age-, sex- and neighbourhood deprivation. The main outcome measure was the prescription of long-term (approximately 12 months use) anticholinergic medications overall (classified according to the Anticholinergic Risk Scale [ARS]), by drug class, individual drugs, and polypharmacy. RESULTS: Adults with n = 1,654 (38.4%), and without n = 3,047 (23.6%), intellectual disabilities were prescribed medications long-term with anticholinergic effects. Of those on such drugs, adults with intellectual disabilities were most likely to be on central nervous system (62.6%), gastrointestinal (46.7%), and cardiovascular (28.4%) medications. They were prescribed more central nervous system, gynaecological/urinary tract, musculoskeletal, and respiratory medications, and less cardiovascular, infection, and endocrine medications than their matched comparators. Regardless of age, sex, or neighbourhood deprivation, adults with intellectual disabilities had greater odds of being prescribed antipsychotics (OR = 5.37 [4.40-6.57], p < 0.001), antiepileptics (OR = 2.57 [2.22-2.99], p < 0.001), and anxiolytics/hypnotics (OR = 1.28 [1.06-1.56], p = 0.012). Compared to the general population, adults with intellectual disabilities were more likely to be exposed to overall anticholinergic polypharmacy (OR = 1.48 [1.33-1.66], p < 0.001), and to psychotropic polypharmacy (OR = 2.79 [2.41-3.23], p < 0.001). CONCLUSIONS: Adults with intellectual disabilities are exposed to a greater risk of having very high anticholinergic burden through polypharmacy from several classes of medications, which may be prescribed by several different prescribers. There is a need for evidence-based recommendations specifically about people with intellectual disabilities with multiple physical and mental ill-health conditions to optimise medication use, reduce inappropriate prescribing and adverse anticholinergic effects.

Umbrella systematic review of systematic reviews and meta-analyses on comorbid physical conditions in people with autism spectrum disorder.

BACKGROUND: Comorbid physical conditions may be more common in people with autism spectrum disorder (ASD) than other people. AIMS: To identify what is and what is not known about comorbid physical conditions in people with ASD. METHOD: We undertook an umbrella systematic review of systematic reviews and meta-analyses on comorbid physical conditions in people with ASD. Five databases were searched. There were strict inclusion/exclusion criteria. We undertook double reviewing for eligibility, systematic data extraction and quality assessment. Prospective PROSPERO registration: CRD42015020896. RESULTS: In total, 24 of 5552 retrieved articles were included, 15 on children, 1 on adults, and 8 both on children and adults. Although the quality of included reviews was good, most reported several limitations in the studies they included and considerable heterogeneity. Comorbid physical conditions are common, and some are more prevalent than in the general population: sleep problems, epilepsy, sensory impairments, atopy, autoimmune disorders and obesity. Asthma is not. However, there are substantial gaps in the evidence base. Fewer studies have been undertaken on other conditions and some findings are inconsistent. CONCLUSIONS: Comorbid physical conditions occur more commonly in people with ASD, but the evidence base is slim and more research is needed. Some comorbidities compound care if clinicians are unaware, for example sensory impairments, given the communication needs of people with ASD. Others, such as obesity, can lead to an array of other conditions, disadvantages and early mortality. It is essential that potentially modifiable physical conditions are identified to ensure people with ASD achieve their best outcomes. Heightening clinicians' awareness is important to aid in assessments and differential diagnoses, and to improve healthcare.

Antipsychotic and antidepressant prescribing for 704 297 children and young people with and without intellectual disabilities: record linkage study.

BACKGROUND: Psychotropics are overprescribed for adults with intellectual disabilities; there are few studies in children and young people. AIMS: To investigate antipsychotic and antidepressant prescribing in children and young people with and without intellectual disabilities, and prescribing trends. METHOD: Scotland's annual Pupil Census, which identifies pupils with and without intellectual disabilities, was record-linked to the Prescribing Information System. Antidepressant and antipsychotic data were extracted. Logistic regression was used to analyse prescribing between 2010 and 2013. RESULTS: Of the 704 297 pupils, 16 142 (2.29%) had a record of intellectual disabilities. Antipsychotic and antidepressant use increased over time, and was higher in older pupils; antipsychotic use was higher in boys, and antidepressant use was higher in girls. Overall, antipsychotics were prescribed to 281 (1.74%) pupils with intellectual disabilities and 802 (0.12%) without (adjusted odds ratio 16.85, 95% CI 15.29-18.56). The higher use among those with intellectual disabilities fell each year (adjusted odds ratio 20.19 in 2010 v. 14.24 in 2013). Overall, 191 (1.18%) pupils with intellectual disabilities and 4561 (0.66%) without were prescribed antidepressants (adjusted odds ratio 2.28, 95% CI 2.03-2.56). The difference decreased each year (adjusted odds ratio 3.10 in 2010 v. 2.02 in 2013). CONCLUSIONS: Significantly more pupils with intellectual disabilities are prescribed antipsychotics and antidepressants than are other pupils. Prescribing overall increased over time, but less so for pupils with intellectual disabilities; either they are not receiving the same treatment advances as other pupils, or possible overprescribing in the past is changing. More longitudinal data are required.

Changes over time in the management of long-term conditions in primary health care for adults with intellectual disabilities, and the healthcare inequality gap.

BACKGROUND: Quality of primary healthcare impacts on health outcomes. This study aimed to quantify trends in good practice and the healthcare inequalities gap. METHOD: Indicators of best-practice management of long-term conditions and health promotion were extracted from primary healthcare records on 721 adults with intellectual disabilities in 2007-2010, and 3638 in 2014. They were compared over time, and with the general population in 2014, using Fisher's Exact test and ordinal regression. RESULTS: Management improved for adults with intellectual disabilities over time (OR = 5.32; CI = 2.69-10.55), but not for the general population (OR = 0.74; CI = 0.34-1.64). However, it remained poorer, but to a lesser extent, compared with the general population (OR = 0.38; CI = 0.20-0.73 in 2014, and OR = 0.05; CI = 0.02-0.12 in 2007-2010). In 2014, health care was comparable to the general population on 49/78 (62.8%) indicators. CONCLUSIONS: The extent of the healthcare inequality gap reduced over this period, but remaining inequalities highlight that further action is still necessary.

The experiences of therapists providing psychological treatment for adults with depression and intellectual disabilities as part of a randomised controlled trial.

BACKGROUND: Health professionals were trained to deliver adapted psychological interventions for depression to people with learning disabilities and depression alongside a supporter. Exploring the delivery of psychological interventions can help increase access to therapy. METHOD: Twenty-seven participants took part in six focus groups, and the data were subject to a Framework Analysis. RESULTS: The structure and focus of the manualised therapies, and the use of specific techniques were perceived as key to service-user engagement. Supporters' involvement was valued by therapists if they had a good relationship and regular contact with the individual they supported. Regular clinical supervision was regarded as vital in understanding their role, assessing progress and delivering the interventions. CONCLUSIONS: The findings highlight that health professionals can embrace a focussed therapeutic role and increase access to psychological therapies for people with intellectual disabilities.

Neurodevelopmental multimorbidity and educational outcomes of Scottish schoolchildren: A population-based record linkage cohort study.

BACKGROUND: Neurodevelopmental conditions commonly coexist in children, but compared to adults, childhood multimorbidity attracts less attention in research and clinical practice. We previously reported that children treated for attention deficit hyperactivity disorder (ADHD) and depression have more school absences and exclusions, additional support needs, poorer attainment, and increased unemployment. They are also more likely to have coexisting conditions, including autism and intellectual disability. We investigated prevalence of neurodevelopmental multimorbidity (≥2 conditions) among Scottish schoolchildren and their educational outcomes compared to peers. METHODS AND FINDINGS: We retrospectively linked 6 Scotland-wide databases to analyse 766,244 children (390,290 [50.9%] boys; 375,954 [49.1%] girls) aged 4 to 19 years (mean = 10.9) attending Scottish schools between 2009 and 2013. Children were distributed across all deprivation quintiles (most to least deprived: 22.7%, 20.1%, 19.3%, 19.5%, 18.4%). The majority (96.2%) were white ethnicity. We ascertained autism spectrum disorder (ASD) and intellectual disabilities from records of additional support needs and ADHD and depression through relevant encashed prescriptions. We identified neurodevelopmental multimorbidity (≥2 of these conditions) in 4,789 (0.6%) children, with ASD and intellectual disability the most common combination. On adjusting for sociodemographic (sex, age, ethnicity, deprivation) and maternity (maternal age, maternal smoking, sex-gestation-specific birth weight centile, gestational age, 5-minute Apgar score, mode of delivery, parity) factors, multimorbidity was associated with increased school absenteeism and exclusion, unemployment, and poorer exam attainment. Significant dose relationships were evident between number of conditions (0, 1, ≥2) and the last 3 outcomes. Compared to children with no conditions, children with 1 condition, and children with 2 or more conditions, had more absenteeism (1 condition adjusted incidence rate ratio [IRR] 1.28, 95% CI 1.27-1.30, p < 0.001 and 2 or more conditions adjusted IRR 1.23, 95% CI 1.20-1.28, p < 0.001), greater exclusion (adjusted IRR 2.37, 95% CI 2.25-2.48, p < 0.001 and adjusted IRR 3.04, 95% CI 2.74-3.38, p < 0.001), poorer attainment (adjusted odds ratio [OR] 3.92, 95% CI 3.63-4.23, p < 0.001 and adjusted OR 12.07, 95% CI 9.15-15.94, p < 0.001), and increased unemployment (adjusted OR 1.57, 95% CI 1.49-1.66, p < 0.001 and adjusted OR 2.11, 95% CI 1.83-2.45, p < 0.001). Associations remained after further adjustment for comorbid physical conditions and additional support needs. Coexisting depression was the strongest driver of absenteeism and coexisting ADHD the strongest driver of exclusion. Absence of formal primary care diagnoses was a limitation since ascertaining depression and ADHD from prescriptions omitted affected children receiving alternative or no treatment and some antidepressants can be prescribed for other indications. CONCLUSIONS: Structuring clinical practice and training around single conditions may disadvantage children with neurodevelopmental multimorbidity, who we observed had significantly poorer educational outcomes compared to children with 1 condition and no conditions.

The relative influence of intellectual disabilities and autism on sensory impairments and physical disability: A whole-country cohort of 5.3 million children and adults.

BACKGROUND: Intellectual disabilities and autism are lifelong and often co-occur. Little is known on their extent of independent association with sensory impairments and physical disability. METHODS: For Scotland's population, logistic regressions investigated age-gender-adjusted odds ratios (OR) of associations, independently, of intellectual disabilities and autism with sensory impairments and physical disability. RESULTS: 1,548,819 children/youth, and 3,746,584 adults. In children/youth, the effect size of intellectual disabilities and autism, respectively, was as follows: blindness (OR = 30.12; OR = 2.63), deafness (OR = 13.98; OR = 2.31), and physical disability (OR = 43.72; OR = 5.62). For adults, the effect size of intellectual disabilities and autism, respectively, was as follows: blindness (OR = 16.89; OR = 3.29), deafness (OR = 7.47; OR = 2.36), and physical disability (OR = 6.04; OR = 3.16). CONCLUSIONS: Intellectual disabilities have greater association with the population burden of sensory impairments/physical disability, but autism is also associated regardless of overlap with intellectual disabilities. These may impact further on communication limitations due to autism and intellectual disabilities, increasing complexity of assessments/management of other health conditions. Clinicians need to be aware of these important issues.

Trends and variations in per capita expenditure on adult intellectual disabilities health and social care across Scotland, and by urban/rural class.

BACKGROUND: Following the global financial crisis in 2007/08, the UK implemented an austerity programme which may impact on services. Scotland comprises both densely populated urban conurbations and highly dispersed remote rural and island communities. METHOD: Expenditure data were extracted from Scottish Government statistics. Per capita expenditure was calculated using adjusted Scotland's 2011 census data. RESULTS: There was a 3.41% decrease in real term expenditure on adult intellectual disabilities services between 2012/13 and 2014/15 (>£32 million). In 2014/15, per capita expenditure on adult intellectual disabilities health care ranged from £1,211 to £17,595; social care from £21,147 to £83,831; and combined health and social care expenditures from £37,703 to £85,929. Per capita expenditure on combined health and social care was greater in rural areas, with more on intellectual disabilities social care, though less on health care. CONCLUSIONS: Scottish expenditure on adult intellectual disabilities services has not kept abreast of rising living costs. It varies considerably across the country: a postcode lottery.

"Getting into it": People with intellectual disabilities' experiences and views of Behavioural Activation and Guided Self-Help for depression.

BACKGROUND: No studies have explored the acceptability of Behavioural Activation and Guided Self-Help interventions for depression with people who have intellectual disabilities. METHOD: Twenty-five participants were purposively sampled from participants taking part in a trial comparing Behavioural Activation with a Guided Self-Help intervention. A framework analysis was used to analyse interviews covering participants' expectations and views of therapy. RESULTS: Participants were largely positive about both interventions. However, they identified specific aspects of each intervention which they had found helpful. All participants valued the therapeutic relationship. The participants also had a number of criticisms and suggestions for improving the therapies. A common concern was the time-limited nature of the interventions and a wish for longer-term help. Overall, both sets of participants felt the interventions had relevance for their wider lives. CONCLUSIONS: The participants reported having positive engagement with the therapies but expressed a wish for longer-term supportive relationships.

Supporting people with intellectual disabilities in psychological therapies for depression: A qualitative analysis of supporters' experiences.

BACKGROUND: Clinicians recommend including carers or others in a supporting role in the therapy as an important adaptation of psychological therapies for people with intellectual disabilities. This nested qualitative study from a larger trial explored supporters' experiences of supporting people with intellectual disabilities receiving behavioural activation or guided self-help therapies for depression. METHOD: Twenty-one purposively sampled supporters were interviewed. The semi-structured interviews were subject to framework analysis, covering expectations of therapy, views of therapy sessions, relationships with therapist and participant, and perceived changes. RESULTS: Supporters were positive about both therapies and reported both therapy-specific and nonspecific therapeutic factors that had significant positive impacts on people's lives. Most supporters reported their involvement contributed to the interventions' effectiveness, and helped establish closer relationships to the people they were supporting. CONCLUSIONS: The presence of supporters within psychological therapies for people with intellectual disabilities can be an effective adaptation to therapies for this population.

Incidence of unipolar and bipolar depression, and mania in adults with intellectual disabilities: prospective cohort study.

BACKGROUND: Incidence and determinants of affective disorders among adults with intellectual disabilities are unknown.AimsTo investigate affective disorder incidence, and determinants of unipolar depression, compared with general population reports. METHOD: Prospective cohort study measuring mental ill health of adults with mild to profound intellectual disabilities living within a defined community, over 2 years. RESULTS: There was 70% cohort retention (n = 651). Despite high mood stabiliser use (22.4%), 2-year incident mania at 1.1% is higher than the general population; 0.3% for first episode (standardised incident ratio (SIR) = 41.5, or 52.7 excluding Down syndrome). For any bipolar episode the SIR was 2.0 (or 2.5 excluding Down syndrome). Depression incidence at 7.2% is similar to the general population (SIR = 1.2), suggesting more enduring/undertreatment given the higher prevalence. Problem behaviours (odds ratio (OR) = 2.3) and life events (OR = 1.3) predict incident unipolar depression. CONCLUSIONS: Depression needs improved treatment. Mania has received remarkably little attention in this population, despite high prevalence and incidence (similar to schizophrenia), and given the importance of clinician awareness for accurate differential diagnosis from attention-deficit hyperactivity disorder and problem behaviours.Declaration of interestNone.

Brain-stem serotonin transporter availability in maternal uniparental disomy and deletion Prader-Willi syndrome.

Prader-Willi syndrome (PWS) is a rare condition because of the deletion of paternal chromosomal material (del PWS), or a maternal uniparental disomy (mUPD PWS), at 15q11-13. Affective psychosis is more prevalent in mUPD PWS. We investigated the relationship between the two PWS genetic variants and brain-stem serotonin transporter (5-HTT) availability in adult humans. Mean brain-stem 5-HTT availability determined by [123I]-beta-CIT single photon emission tomography was lower in eight adults with mUPD PWS compared with nine adults with del PWS (mean difference -0.93, t = -2.85, P = 0.014). Our findings confirm an association between PWS genotype and brain-stem 5-HTT availability, implicating a maternally expressed/paternally imprinted gene, that is likely to account for the difference in psychiatric phenotypes between the PWS variants. Declaration of interest None.

Hospital admissions for physical health conditions for people with intellectual disabilities: Systematic review.

BACKGROUND: People with intellectual disabilities may have inequalities in hospital admissions compared with the general population. The present authors aimed to investigate admissions for physical health conditions in this population. METHODS: The present authors conducted a systematic review, searching six databases using terms on intellectual disabilities and hospital admission. Papers were selected based on pre-defined inclusion/exclusion criteria, data extracted, tabulated and synthesized and quality assessed. PROSPERO registration number: CRD42015020575. RESULTS: Seven of 29,613 papers were included. There were more admissions, and a different pattern of admissions (more medical and dental), for people with intellectual disabilities, but most studies did not take account of higher disease prevalence. Three papers considered admissions for ambulatory care-sensitive conditions, two of which accounted for disease prevalence (asthma, diabetes) and found higher admission rates for people with intellectual disabilities. CONCLUSION: Admissions are common. Asthma and diabetes admission data suggest suboptimal primary health care for people with intellectual disabilities compared with the general population, but evidence is limited.

Early death and causes of death of people with Down syndrome: A systematic review.

BACKGROUND: It is thought that people with Down syndrome die younger than the general population, but that survival rates are improving. METHODS: Five databases were searched for keywords related to intellectual disabilities, Down syndrome and mortality. Strict inclusion criteria were applied. Information from 34 selected studies was tabulated, extracted and synthesized. RESULTS: People with Down syndrome died about 28 years younger than the general population. Congenital heart anomalies, comorbidities, low birthweight, and Black and minority ethnicity influenced earlier age of death, as did younger maternal age and poorer parental education. Congenital heart anomalies and respiratory conditions were the leading causes of death, and more common than in the general population. Survival rates have improved over time, particularly for those with congenital heart anomalies. CONCLUSIONS: People with Down syndrome are living longer but still die younger of different causes than the general population. More robust comparative data are needed, and ethnic differences require further study.

Early death and causes of death of people with intellectual disabilities: A systematic review.

BACKGROUND: Death of people with intellectual disabilities is considered to be earlier than for the general population. METHODS: Databases were searched for key words on intellectual disabilities and death. Strict inclusion/exclusion criteria were used. Information was extracted from selected papers, tabulated and synthesized. Prospero registration number: CRD42015020161. RESULTS: Of 19,111 retrieved articles, 27 met criteria. Death was earlier by 20 years. It has improved in recent decades; however, the same inequality gap with the general population remains. More severe intellectual disabilities, and/or additional comorbidities rendered it shortest. Standardized mortality rates showed a greater inequality for women than men. Respiratory disease and circulatory diseases (with greater congenital and lesser ischaemic disease compared with the general population) were the main causes of death. Cancer was less common, and cancer profile differed from the general population. Some deaths are potentially avoidable. All research is from high-income countries, and cause of death is surprisingly little investigated. CONCLUSIONS: Improved health care, including anticipatory care such as health checks, and initiatives addressing most relevant lifestyle behaviours and health risks are indicated.

Management and prevalence of long-term conditions in primary health care for adults with intellectual disabilities compared with the general population: A population-based cohort study.

BACKGROUND: In the UK, general practitioners/family physicians receive pay for performance on management of long-term conditions, according to best-practice indicators. METHOD: Management of long-term conditions was compared between 721 adults with intellectual disabilities and the general population (n = 764,672). Prevalence of long-term conditions was determined, and associated factors were investigated via logistic regression analyses. RESULTS: Adults with intellectual disabilities received significantly poorer management of all long-term conditions on 38/57 (66.7%) indicators. Achievement was high (75.1%-100%) for only 19.6% of adults with intellectual disabilities, compared with 76.8% of the general population. Adults with intellectual disabilities had higher rates of epilepsy, psychosis, hypothyroidism, asthma, diabetes and heart failure. There were no clear associations with neighbourhood deprivation. CONCLUSIONS: Adults with intellectual disabilities receive poorer care, despite conditions being more prevalent. The imperative now is to find practical, implementable means of supporting the challenges that general practices face in delivering equitable care.

What Effect Does Transition Have on Health and Well-Being in Young People with Intellectual Disabilities? A Systematic Review.

BACKGROUND: Transition to adulthood might be a risk period for poor health in people with intellectual disabilities. However, the present authors could find no synthesis of evidence on health and well-being outcomes during transition in this population. This review aimed to answer this question. METHOD: PRISMA/MOOSE guidelines were followed. Search terms were defined, electronic searches of six databases were conducted, reference lists and key journals were reviewed, and grey literature was searched. Papers were selected based on clear inclusion criteria. Data were extracted from the selected papers, and their quality was systematically reviewed. The review was prospectively registered on PROSPERO: CRD42015016905. RESULTS: A total of 15 985 articles were extracted; of these, 17 met the inclusion criteria. The results of these articles were mixed but suggested the presence of some health and well-being issues in this population during transition to adulthood, including obesity and sexual health issues. CONCLUSION: This review reveals a gap in the literature on transition and health and points to the need for future work in this area.

Month of Conception and Learning Disabilities: A Record-Linkage Study of 801,592 Children.

Learning disabilities have profound, long-lasting health sequelae. Affected children born over the course of 1 year in the United States of America generated an estimated lifetime cost of $51.2 billion. Results from some studies have suggested that autistic spectrum disorder may vary by season of birth, but there have been few studies in which investigators examined whether this is also true of other causes of learning disabilities. We undertook Scotland-wide record linkage of education (annual pupil census) and maternity (Scottish Morbidity Record 02) databases for 801,592 singleton children attending Scottish schools in 2006-2011. We modeled monthly rates using principal sine and cosine transformations of the month number and demonstrated cyclicity in the percentage of children with special educational needs. Rates were highest among children conceived in the first quarter of the year (January-March) and lowest among those conceived in the third (July-September) (8.9% vs 7.6%; P < 0.001). Seasonal variations were specific to autistic spectrum disorder, intellectual disabilities, and learning difficulties (e.g., dyslexia) and were absent for sensory or motor/physical impairments and mental, physical, or communication problems. Seasonality accounted for 11.4% (95% confidence interval: 9.0, 13.7) of all cases. Some biologically plausible causes of this variation, such as infection and maternal vitamin D levels, are potentially amendable to intervention.

Epidemiology of autism in adults across age groups and ability levels.

BACKGROUND: The epidemiology of autism in adults has relied on untested projections using childhood research. AIMS: To derive representative estimates of the prevalence of autism and key associations in adults of all ages and ability levels. METHOD: Comparable clinical diagnostic assessments of 7274 Adult Psychiatric Morbidity Survey participants combined with a population case-register survey of 290 adults with intellectual disability. RESULTS: The combined prevalence of autism in adults of all ages in England was 11/1000 (95% CI 3-19/1000). It was higher in those with moderate to profound intellectual disability (odds ratio (OR) = 63.5, 95% CI 27.4-147.2). Male gender was a strong predictor of autism only in those with no or mild intellectual disability (adjusted OR = 8.5, 95% CI 2.0-34.9; interaction with gender, P = 0.03). CONCLUSIONS: Few adults with autism have intellectual disability; however, autism is more prevalent in this population. Autism measures may miss more women with autism.

Reaction time in adolescence, cumulative allostatic load, and symptoms of anxiety and depression in adulthood: the West of Scotland Twenty-07 Study.

OBJECTIVE: To examine the relation between reaction time in adolescence and subsequent symptoms of anxiety and depression and investigate the mediating role of sociodemographic measures, health behaviors, and allostatic load. METHODS: Participants were 705 members of the West of Scotland Twenty-07 Study. Choice reaction time was measured at age 16. At age 36 years, anxiety and depression were assessed with the 12-item General Health Questionnaire (GHQ) and the Hospital Anxiety and Depression Scale (HADS), and measurements were made of blood pressure, pulse rate, waist-to-hip ratio, and total and high-density lipoprotein cholesterol, C-reactive protein, albumin, and glycosolated hemoglobin from which allostatic load was calculated. RESULTS: In unadjusted models, longer choice reaction time at age 16 years was positively associated with symptoms of anxiety and depression at age 36 years: for a standard deviation increment in choice reaction time, regression coefficients (95% confidence intervals) for logged GHQ score, and square-root-transformed HADS anxiety and depression scores were 0.048 (0.016-0.080), 0.064 (0.009-0.118), and 0.097 (0.032-0.163) respectively. Adjustment for sex, parental social class, GHQ score at age 16 years, health behaviors at age 36 years and allostatic load had little attenuating effect on the association between reaction time and GHQ score, but weakened those between reaction time and the HADS subscales. Part of the effect of reaction time on depression was mediated through allostatic load; this mediating role was of borderline significance after adjustment. CONCLUSIONS: Adolescents with slower processing speed may be at increased risk for anxiety and depression. Cumulative allostatic load may partially mediate the relation between processing speed and depression.