Background Many studies have evaluated the prevalence of intellectual disability (ID) by focusing on different ages during childhood and adolescence. Although the prevalence of ID is higher in older age groups, how cumulative prevalence increases, and what level it reaches before adulthood, remains unclear.Method We used Care Register for Health Care to retrieve information on individuals born in 1996-2007 with any of the inclusion diagnoses of ID (F7 group and/or aetiological diagnoses) for the period 1996 to 2013. The cumulative prevalence was calculated as percentages for every age based on Finnish population data.Results The registration of new diagnoses of ID continued steadily throughout the developmental years. The cumulative prevalence reached 1.19% by age 17.5 among those born in 1996. Later-born age groups appeared to receive their first ID diagnoses earlier in childhood. Those born in 1999 reached a cumulative prevalence of 1.21% already by age 14.5. Of all those with ID, 67% had an F7 diagnosis only, 42% had an aetiological diagnosis only and 9% had both diagnoses.Conclusions Cumulative prevalence of ID by year, until the age of 18, will provide a better estimate and understanding of the prevalence of ID than a point prevalence at any one point during the developmental years.

BACKGROUND:In the national study of multiple registers in 2000, the average prevalence of intellectual disability (ID) was 0.70%, with marked differences by age group (range 0.38-0.96%) - what are these differences in detail, and can they be understood?METHOD:This study was based on two national health registers and six social benefit registers. Prevalence of ID was calculated by 1-year age cohorts.RESULTS:The multiple register prevalence of ID increased steadily from 0.20% in the first life year to 0.74% (male: 0.90%, female: 0.58%) at 10 years. For boys, the rate fell to 0.71% at 11 years. For both sexes, a steady increase was noted in the distribution up to 40 years (male: 0.84%, female: 0.73%), followed by a sharper increase to the maximum prevalence (male: 1.19% at 48 years, female: 1.05% at 50 years). At the pension age of 66 years, a sudden drop to 0.49% occurred for men and women. Different registers gave very different age distributions.CONCLUSIONS:By examining the data by 1-year age cohorts, and by understanding the role of each register, it could be deduced that a proportion of cases in younger age groups is lacking, and a remarkable proportion of elderly ID persons is missing from the pooled data. The findings were more difficult to interpret, if the data were grouped into bigger age groups.

To determine whether exposure to prenatal ultrasound increases non‐right‐handedness in boys.

Anti-myelin basic protein (MBP) antibodies in pediatric-onset MS and controls were characterized. Serum samples were obtained from 94 children with MS and 106 controls. Paired CSF and serum were obtained from 25 children with MS at time of their initial episode of acute demyelinating syndrome (ADS). Complementary assays were applied across samples to evaluate the presence, and the physical binding properties, of anti-MBP antibodies. While the prevalence and titers of serum anti-MBP antibodies against both immature and mature forms of MBP were similar in children with MS and in controls, binding characteristics and formal Surface Plasmon Resonance (SPR) studies indicated surprisingly high binding affinities of all pediatric anti-MBP antibodies. Serum levels of anti-MBP antibodies correlated significantly with their CSF levels, and their presence in children with MS was associated with significantly increased risk of an acute disseminated encephalomyelitis-like initial clinical presentation. While antibodies to both immature and mature forms of MBP can be present as part of the normal pediatric humoral repertoire, these anti-myelin antibodies are of surprisingly high affinity, can access the CNS during inflammation, and have the capacity to modulate disease expression. Our findings identify an immune mechanism that could contribute to the observed heterogeneity in spectrum of clinical presentations in early-onset MS.

Based on a meta-analysis by Torloni et al(2008), we hypothesise that ultrasound exposure decreases the head circumference and height of newborns. The effects of ultrasound on head circumference and birth height were studied in the Helsinki Ultrasound Trial with 7773 subjects. We used intention-to-treat method and further linear regression analysis with covariates. We excluded subjects whose height or head circumference were in either of the 1% extremes of the distribution. The linear regression results are presented in the attached table with raw and adjusted models of the measures. For height only 3 estimates are shown. Our results support the hypothesis that ultrasound exposure decreases head circumference, but not birth height. Mother's smoking had the largest independent effect on both of the measures. The result confirms the known association of maternal smoking and reduced birth size.

The initial hypothesis was whether prenatal ultrasound increases nonright-handedness. The association was tested on the Helsinki Ultrasound Trial Data, that consists of birth records collected in 1985–1987. (Saari-Kemppainen et al, Lancet 1990,336 : 387–91) Handedness was assessed by a questionnaire in the year 2000 with 4174 acceptable answers (54%). The first approach was the case-control setting. The intention-to-treat approach was followed by an extended per-protocol analysis, where excluded groups were also analyzed, to clarify potential confounder phenomena. The exploratory phase consisted of a trimesterwise probe of the associations with handedness. Trimester 2 was divided into 3 separate equally sized time window groups. Two additional variables were added to models. Testing was done with logistic regression using Stata statistical package. Intention-to-treat: For boys and girls together odds ratio was 1.16 (0.98–1.37). Per-protocol analysis: no significance, odd ratio was 1.25 (0.84–1.87) The excluded groups had significantly lower prevalence for nonright-handedness. Timing effects with trimesterwise indicators were tested in models and results are tabulated here: The unexpected results were the lower incidence of nonright-handedness in trimesters 1 and 3, for girls and boys, respectively, and the effect of smoking cessation of mother on handedness. Conflicting results in previous studies may be explained by how much trimesters 1 and 3 are involved in analysis, depending on the applied study policy and timing of extra scans. Our study did not necessarily make a distinction between ultrasound effects and confounders, but has the timing effect and its sex specificity. Trimester change may change the direction of the association. In conclusion, despite of the significant sex specific effects, their underlying causes remain unknown, so far. Thus the original hypothesis could not be confirmed.

The mental health, adaptive behaviour and intellectual abilities of people with Down syndrome (n=129) were evaluated in a population-based survey of social and health care records. Females had better cognitive abilities and speech production compared with males. Males had more behavioural problems than females. Behaviour suggestive of attention deficit hyperactivity disorder was often seen in childhood. Depression was diagnosed mainly in adults with mild to moderate intellectual disability. Autistic behaviour was most common in individuals with profound intellectual disability. Elderly people often showed decline of adaptive behaviour associated with Alzheimer's disease. Case descriptions are presented to illustrate the multitude of mental health and behavioural issues seen from childhood to old age in this population.

Background: Children with intellectual disability (ID) have a higher risk for psychiatric disturbance than their peers with normal intelligence, but research data on risk factors are insufficient and partially conflicting.Methods: The subjects comprised 75 children with ID aged 6-13 years. Data were obtained from case files and the following four questionnaires completed by their parents or other carers: Developmental Behaviour Checklist, American Association of Mental Deficiency (AAMD) Adaptive Behavior Scale, a questionnaire on additional disabilities, and a questionnaire on family characteristics and child development.Results: The risk of psychopathology was most significantly increased by moderate ID, limitations in adaptive behaviour, impaired language development, poor socialization, living with one biological parent, and low socio-economic status of the family.Conclusions: The risk of psychopathology in children with ID is increased by factors related to family characteristics and child development. Identifying these factors will help diagnose and possibly prevent psychiatric disorders in these children.

Forty-nine people with intellectual disability (ID) were examined for their sleep by using clinical examination, sleep diaries, actigraphy, polysomnography and multiple sleep latency test. The patients had sleep difficulties, difficult-to-treat seizures, behavioural problems and heavy multi-drug therapy. There were 30 males and 19 females with the age range from 4 to 64 years. All subjects suffered from some type of sleep disorder. Sleep apnoea was the most common sleep disorder (N=22), followed by insomnia (N=12) and restless legs syndrome/periodic limb movements (N=10). Eight of ten patients with Down syndrome had sleep apnoea. Sleep disorders appear to be underdiagnosed in ID people with intractable seizures and behavioural difficulties. After appropriate therapy the patients did better and their drug regimen could be reduced.

Structured checklists have been used to supplement psychiatric assessment of children with normal intelligence, but for children with intellectual disability, only a few checklists exist. We evaluated the Child Behavior Checklist (CBCL) in the assessment of psychopathology in Finnish children with intellectual disability. The CBCL was completed by parents or other carers of 90 children aged 6–13 years. Of the 118 CBCL problem items, the lowest scores were for ‘Suicidal talks’ and ‘Alcohol, drugs’, and the highest score for ‘Acts too young’. Total Problem, Internalizing, and Externalizing scores were highest among children with moderate intellectual disability and lowest among those with profound intellectual disability. Externalizing scores were significantly higher among children with mild or moderate intellectual disability than among those with severe or profound intellectual disability. Compared with the original normative samples, Total Problem scores were higher in the present study. With a T-score cut-off point of 60, the rated frequency of psychiatric disorders was 43%. We conclude that, despite certain limitations, the CBCL can be used in the assessment of psychopathology among children with mild intellectual disability but is less reliable for those with moderate, severe, or profound intellectual disability.

We investigated the integrity of striatal dopaminergic system in seven patients with dopa-responsive dystonia (DRD). Dopamine transporter function ([11C]CFT) and D1 ([11C]NNC 756) and D2 receptors ([11C]raclopride) were studied in same patients using positron emission tomography. Compared to age-adjusted control values the dopamine D2 receptor availability was increased in DRD. The mean age-adjusted [11C]raclopride uptake was 116% of the control mean in the putamen (p = 0.004) and 114% in the caudate nucleus (p = 0.007). The mean [11C]NNC 756 uptake was not different between DRD patients and controls, the age-adjusted uptake in DRD being 93% of mean control value in the putamen (p = 0.20) and 95% in the caudate nucleus (p = 0.40).