Maladaptive behaviours and symptoms of dementia in adults with Down's syndrome compared with adults with intellectual disability of other aetiologies

Dementia commonly occurs in elderly people with intellectual disability, especially those with Down's syndrome. The non-cognitive symptoms of dementia can be of greater significance to individuals and carers than the cognitive changes caused by this condition. It is not known whether there are differences between people with Down's syndrome and those with intellectual disability of other causes with regard to the prevalence of such symptoms. The present study was undertaken to draw a comparison between a group with Down's syndrome and dementia ( n = 19), and a group with intellectual disability of other causes and dementia ( n = 26). Maladaptive behaviours and psychiatric symptomatology were assessed in both groups. The group with Down's syndrome had a higher prevalence of low mood, restlessness/excessive overactivity, disturbed sleep, being excessively uncooperative and auditory hallucinations. Aggression occurred with greater frequency in those subjects with intellectual disability of other causes. These findings are of epidemiological importance in terms of service planning and understanding psychiatric presentation.     

Thyroid replacement therapy in Down's syndrome with hypothyroidism.

Three elderly subjects with Down's syndrome and biochemical evidence of hypothyroidism were investigated before and after four months of thyroid replacement treatment. The patients' appearance was demonstrated by photographs and the biochemical thyroid values and the intellectual performance were assessed. The appearance before treatment varied from a florid myxoedematous appearance to a state without features indicating myxoedema. Thyroid replacement therapy was given in usual dose and the biochemical response was similar to that seen in normal subjects. The intellectual performance improved little or not at all. The characteristic discomfort usually associated with hypothyroidism was very pronounced in one case and disappeared totally during treatment. It is concluded that the diagnosis of hypothyroidism in elderly subjects with Down's syndrome can be very difficult when based on appearance and history alone and biochemical thyroid tests are often necessary. The patients should be treated with replacement therapy just as other patients suffering from hypothyroidism.     

Down's syndrome: intellectual and behavioural functioning during adulthood

ABSTRACT. Previous cross–sectional studies of Down's syndrome have suggested thatdeficits in cognitive and neurological functioning after the age of 35 years are symptomatic of Alzheimer's disease. It has been claimed that this pattern corresponds to post-mortem neuropathological findings of Alzheimer's disease in all Down's syndrome patients who die aged over 35 years. In the present study of Down's syndrome patients aged between 19 and 49 years, results showed that, for those over 35 years, intellectual deterioration had occurred in less than a third. No relationship was found between chronological age and the level of self care skills or the presence of disturbed behaviour. Results are discussed in terms of the interpretation of the existing neuropathological literature, the methodology of future studies and clinicaldecisions regarding hospitalized patients with Down's syndrome.     

Ageing and mental health problems in people with intellectual disability

PURPOSE OF REVIEW: Increasing numbers of people with intellectual disability are now living well into old age. This paper will review the recent literature pertaining to the mental health of older people with intellectual disability. RECENT FINDINGS: Overall, the prevalence of mental health problems is high in adults of all ages with intellectual disability. A major epidemiological study did not report sufficient detail to examine the effect of ageing on specific disorders or the differential effects of ageing and early mortality in people with Down's syndrome. At least a third of people with Down's syndrome can expect to develop Alzheimer's disease in middle age whilst for other people with intellectual disability, Alzheimer's disease is probably no more common than in the general population. Diagnosis and management of dementia is complicated by the high rates of comorbid physical and mental health problems. SUMMARY: Overall, mental health problems in older people with intellectual disability are similar to younger people with intellectual disability, however there are more cases of dementia and physical health problems. Further research is needed to improve our understanding of the effects of ageing on the mental health and care needs of older people with intellectual disability.     

Daytime behaviour problems and maternal stress in children with Down's syndrome, their siblings, and non-intellectually disabled and other intellectually disabled peers

The present study investigates the occurrence of daytime behaviour problems and mammal stress in a group of children with Down's syndrome (DS) compared with a group of their non-intellectually disabled siblings, a group of non-intellectually disabled children from the general population and a group of children with an intellectual disability other than Down's syndrome. The Aberrant Behavior Checklist (ABC) and the Malaise Inventory were completed by the mothers. Associations between daytime behaviour problems and maternal stress were also explored. Overall, the children with DS and the children with other intellectual disabilities showed significantly higher rates of behavioural disturbance on all five of the ABC subscales (Irritability, Lethargy, Stereotypies, Hyperactivity and Inappropriate Speech) and on the Total ABC score. However, the children with other intellectual disabilities also showed significantly higher scores than the children with DS on four of the ABC subscales: Irritability, Lethargy, Stereotypies and Hyperactivity, as well as the Total ABC score. The siblings and children from the general population showed very similar behaviour scores. A number of significant age and sex differences were found in the occurrence of daytime behaviour problems. Maternal stress was significantly higher in the group with other forms of intellectual disability than the other three groups, and a number of significant associations were found between parental ratings of daytime behaviour problems and maternal stress in all four samples. The implications of the findings are discussed, including the need for early assessment to minimize adverse effects on the child's development and on family life.     

Speech dysfluency and manual specialization in Down's syndrome

ABSTRACT. The relationship between speech dysfluency and manual lateralisation was studied in 31 adults with Down's syndrome. Analysis of speech samples from videotapes indicated that frequency of dysfluency ranged from normal to very severe; 42% of the subjects were stutterers. Manual lateralization was measured by the demonstrated use of five objects (pencil, comb, toothbrush, ball and scissors); 61% of the subjects had a clear right-hand preference, 13% a left-hand preference, and the remaining subjects (39%) were mixed-handed. Increased dysfluency was associated with increased non-right-handedness, and this finding could not be explained by reference to either generalized linguistic or intellectual deficits. Results suggest individual variation in the speech motor control system in adults with Down's syndrome which may be associated with anomalous cerebral dominance.     

Cognitive functioning of juveniles with Down syndrome and other forms of mental retardation

The performance of juvenile Down syndrome individuals and two groups of oligophrenes was compared in several cognitive tests. All three groups of subjects were of the same CA, the Down's and one group of mentally retarded non-Down's had an average MA of 62, the other group an MA of 86 months. Though the group with the highest mental age usually outperformed the other two, significant differences were rare. It is concluded that at this age Down's and mentally retarded with different etiologies generally have rather similar cognitive abilities and that the intellectual deterioration of Down's, which at a later age inevitably leads to Alzheimer's disease, indeed starts only at a later CA.     

Fragile-X syndrome, Down's syndrome and autism: awareness and knowledge amongst special educators

Fragile-X syndrome is the commonest cause of inherited intellectual disability. There is good evidence for a behavioural phenotype. This has implications for school staff using standard educational techniques. Similarly, autism is known to create particular educational requirements. The present study examined the awareness and knowledge of fragile-X syndrome, Down's syndrome and autism amongst staff in special and mainstream education. One hundred and two special school staff and 40 mainstream school staff completed questionnaires. Most staff offered a variety of features 'typical' of Down's syndrome and autism. In contrast, staff knew less about fragile-X syndrome. Specific knowledge about the learning styles of these children was very poor, but was associated with having taught an affected child. Mainstream and special school staff offered similar levels of knowledge for all three conditions. Staff did not demonstrate a sufficiently specialized knowledge of fragile-X syndrome to ensure that the special educational needs of these children were being met fully.     

The relationship between the effect of setting a goal on standing broad jump performance and behaviour regulation ability in children with intellectual disability

The objectives of the present study were to investigate the differences in standing broad jump performance between two task conditions (with and without goal) and to clarify the relation of verbal behaviour regulation to this difference in children with intellectual disability. The subjects were 30 children with intellectual disability with an average age of 16.2 years. In the without-goal condition, subjects were instructed to jump as far as possible. In the with-goal condition, on the other hand, subjects were given a goal set 20 cm away from the distance of the first trial in the without-goal condition and instructed to jump for the goal. Verbal behaviour regulation ability was measured by three tasks on Garfield's motor impersistence test: keeping eyes closed, protruding tongue with eyes open and keeping mouth open. The mean performance of the with-goal condition was 108 cm, while that of the without-goal condition was 102 cm. The difference between these results was significant, thus indicating the effectiveness of setting a goal to improve jumping performance. Among three independent variables (chronological age, IQ and behaviour regulation score), only the behaviour regulation score was found to be significantly related to the condition difference. It was more effective to demonstrate the goal when the behaviour regulation abilities of the children were lower, but giving the children a goal was not effective for subjects with Down's syndrome. Children with Down's syndrome were considered to have a deficiency in the motor ability itself, not in the system for expressing the motor ability.     

Abnormal serum immunoglobulin levels in Down's syndrome patients.

Serum immunoglobulin levels were measured in 20 patients with Down's syndrome and 16 mentally retarded cerebral palsy control patients. Significant elevation of IgG and IgD levels were found in the Down's syndrome as compared with the control patients. Serum IgD level in Down's syndrome individuals significantly decreased with increasing age. Serum IgA level was significantly elevated in older Down's syndrome patients but showed no change in younger Down's syndrome patients. Serum IgM and IgE levels were slightly elevated in Down's syndrome patients, but these differences were not significant. The elevated immunoglobulin levels in Down's syndrome individuals seem to be a response to increased frequency of infection.     

Underestimating the educability of Down's syndrome children: examination of methodological problems in recent literature.

For many years, the educational capabilities of Down's syndrome persons have been underestimated because a large number of studies purporting to give an accurate picture of Down's syndrome persons' developmental capabilities have had serious methodological flaws. A close examination of that literature, coupled with a look at findings from two current early education projects for Down's syndrome children, revealed that psychometrically defined educability is far more common in Down's syndrome persons than a cursory review of the literature would lead to believe.     

Comparative coherence studies in healthy volunteers and Down's syndrome patients from childhood to adult age.

Within the scope of the Munich Pediatric Longitudinal Study, EEG coherence was studied in 212 Down's syndrome patients and 342 healthy controls aged from 6 months up to 30 years. The digitalized EEG records were subjected to spectral analysis. Frequency band-related coherences were calculated to reveal age-specific differences in the functional relationship between two brain areas in Down's syndrome patients and controls. The results show that in the "eyes-open" state the intra-hemispheric coherence in the alpha band was significantly lower (P less than 0.05) in the Down's syndrome patients than in the controls whereas that in the delta bands it was generally higher. The intra-hemispheric coherence in the "eyes-closed" state was generally higher in the Down's syndrome groups than in the controls; however, significant differences could be detected only in some age groups. The age-specific development of coherence in the inter-hemispheric parieto-occipital region was almost identical in Down's syndrome children as in controls, both with open and closed eyes. The most distinct differences were found in the fronto-central inter-hemispheric coherence (P less than 0.01), while the coherence deficiencies in the Down's syndrome group became more prominent with increasing age from school age onwards. These electrophysiological results are compared with the results of neuropathological and neurophysiological studies of other authors. It can be suggested that there are correlations with a significantly small number of dendritic spines in Down's syndrome patients, which was determined in neuropathological examinations. A neuronal model of interpretation is presented which explains the increasing developmental deficit with age in Down's syndrome children.     

Decline in cerebral glucose utilisation and cognitive function with aging in Down''s syndrome.

The cerebral metabolic rate for glucose (CMRglc) was measured with positron emission tomography and [18F]2-fluoro-2-deoxy-D-glucose in 14 healthy subjects with Down's syndrome, 19 to 33 years old, and in six healthy Down's syndrome subjects over 35 years, two of whom were demented. Dementia was diagnosed from a history of mental deterioration, disorientation and hallucinations. All Down's syndrome subjects were trisomy 21 karyotype. CMRglc also was examined in 15 healthy men aged 20-35 years and in 20 healthy men aged 45-64 years. All subjects were at rest with eyes covered and ears plugged. Mean hemispheric CMRglc in the older Down's syndrome subjects was significantly less, by 23%, than in the young Down's syndrome group; statistically significant decreases in regional metabolism (rCMRglc) also were present in all lobar regions. Comparison of the younger control group with the older control group showed no difference in CMRglc or any rCMRglc (p greater than 0.05). Assessment of language, visuospatial ability, attention and memory showed significant reductions in test scores of the old as compared with the young Down's syndrome subjects. These results show that significant age differences in CMRglc and rCMRglc occur in Down's syndrome but not in healthy controls, and that, although only some older Down's syndrome subjects are demented, significant age reductions in neuropsychologic variables occur in all of them.     

Abnormal pinna type and hearing loss correlations in Down's syndrome

ABSTRACT. Significant hearing loss and external pinna malformations are two of the most common defects evident in Down's syndrome. The external and middle ears are linked embryologically, both arising from the first and second branchial arches. Evidence indicates that the majority of hearing loss in Down's syndrome is conductive in nature, originating from malformations of the middle ear ossicles and/or the eustachian tube. Recent studies also have indicated that hearing loss is a contributing factor to the IQ and learning deficits that afflict most individuals with Down's syndrome. Therefore, an early, external diagnostic feature for predicting conductive hearing loss would be desirable. In the current study, people with Down's syndrome, people with non-Down's mental retardation and control subjects were examined in a clinical environment for the presence of hearing loss and pinna defects. It was found that 90% of the Down's syndrome population had significant hearing loss, compared to slightly more than 50% in the non-Down's group and no hearing loss in the controls. Also, the majority of hearing loss among individuals with Down's syndrome was conductive, while all hearing loss in the non-Down's group was sensorineural The Down's syndrome population exhibited nearly 3.5 pinna defects per ear, with malformations of the helix being very evident. The non-Down's population exhibited 2.5 pinna defects per ear, with concha defects being the most common.     

MRI volumes of the hippocampus and amygdala in adults with Down's syndrome with and without dementia

OBJECTIVE: This study sought to determine whether volumes of the hippocampus and amygdala are disproportionately smaller in subjects with Down's syndrome than in normal comparison subjects and whether volume reduction is greater in Down's syndrome subjects with dementia. METHOD: The subjects were 25 adults with Down's syndrome (eight with dementia) and 25 cognitively normal adults who were individually matched on age, sex, and race. Magnetic resonance imaging measures included volumes of the hippocampus, amygdala, and total brain. Nineteen of the Down's syndrome subjects had follow-up scans (interscan interval = 9-41 months). RESULTS: Nondemented Down's syndrome subjects had significantly smaller volumes of the hippocampus, but not the amygdala, than their comparison subjects, even when total brain volume was controlled for. Volumes of both the hippocampus and the amygdala were smaller in the demented Down's syndrome subjects than in their comparison subjects, even when total brain volume was controlled for. Age was not correlated with volume of the hippocampus or amygdala among the nondemented Down's syndrome subjects and the comparison subjects; age was correlated with volume of the amygdala, but not the hippocampus, among the Down's syndrome subjects with dementia. Changes in volume over time were not statistically significant for either the demented or the nondemented subjects. CONCLUSIONS: Hippocampal volume, while disproportionately small for brain size in individuals with Down's syndrome, remains fairly constant through the fifth decade of life in those without dementia. All subjects over age 50 who had Down's syndrome demonstrated volume reduction in the hippocampus as well as clinical signs of dementia. Dementia was also associated with volume reductions in the amygdala that exceeded reductions in total brain volume.     

Effect of preconditioning visual stimulus duration on visual-evoked responses to a subsequent test flash in Down's syndrome and nonretarded individuals.

Visual-evoked responses to a visual test flash preceded by three different durations of a visual conditioning flash having the same intensity and form were recorded from 8 Down's syndrome subjects and 9 nonretarded CA-matched control subjects. Both groups showed a significant decrease in visual-evoked response perimeters to the test flash as the duration of the visual conditioning flash increased from 1 to 100 msec. For the 1000-msec condition, perimeters of Down's syndrome subjects showed a significant increase, and this was significantly greater than the nonretarded group. These results suggest that Down's syndrome individuals have deficits in their neural processing of sensory information.?23Author     

Life span changes in the averaged evoked responses of Down's syndrome and nonretarded persons.

Visual, auditory, and somatosensory evoked responses were recorded from six age groups of Down's syndrome persons and age and sex-matched nonretarded individuals ranging in age from 5 to 62 years and assigned to groups on the basis of observable signs of development and aging. Results indicated that, regardless of stimulus modality, the amplitude of late wave components was dramatically larger for Down's syndrome than for the nonretarded subjects. Where obvious amplitude reduction occurred with maturation and aging among nonretarded subjects, amplitude changes were generally absent among Down's syndrome subjects. The findings for Down's syndrome persons were discussed in terms of deficits in central inhibition and abnormalities in neuronal excitability to different levels of stimulus intensity.     

Performance of persons with Down's syndrome on two projective techniques.

A comparison was made of the Rorschach responses and the Human Figure Drawings of a group of 21 Down's syndrome subjects and the responses of a group of 21 other mentally retarded persons (non-Down's syndrome group). Statistically significant differences on the Rorschach were indicative of a better differentiated visual perceptual ability in the Down's syndrome group. The traditional stereotype of the person with Down's syndrome as having a better self-concept and being more affectionate and cooperative was supported by the Rorschach results. This was not substantiated by the Human Figure Drawings, in which the non-Down's syndrome group performed significantly better than the Down's syndrome group.     

Neuroanatomy of Down's syndrome: a high-resolution MRI study

OBJECTIVE: Down's syndrome, the most common genetic cause of mental retardation, results in characteristic physical and neuropsychological findings, including mental retardation and deficits in language and memory. This study was undertaken to confirm previously reported abnormalities of regional brain volumes in Down's syndrome by using high-resolution magnetic resonance imaging (MRI), determine whether these volumetric abnormalities are present from childhood, and consider the relationship between neuroanatomic abnormalities and the cognitive profile of Down's syndrome. METHOD: Sixteen children and young adults with Down's syndrome (age range=5-23 years) were matched for age and gender with 15 normal comparison subjects. High-resolution MRI scans were quantitatively analyzed for measures of overall and regional brain volumes and by tissue composition. RESULTS: Consistent with prior imaging studies, subjects with Down's syndrome had smaller overall brain volumes, with disproportionately smaller cerebellar volumes and relatively larger subcortical gray matter volumes. Also noted was relative preservation of parietal lobe gray and temporal lobe white matter in subjects with Down's syndrome versus comparison subjects. No abnormalities in pattern of brain asymmetry were noted in Down's syndrome subjects. CONCLUSIONS: The results largely confirm findings of previous studies with respect to overall patterns of brain volumes in Down's syndrome and also provide new evidence for abnormal volumes of specific regional tissue components. The presence of these abnormalities from an early age suggests that fetal or early postnatal developmental differences may underlie the observed pattern of neuroanatomic abnormalities and contribute to the specific cognitive and developmental deficits seen in individuals with Down's syndrome.     

Assessment of counseling practices at the birth of a child with Down's syndrome.

An attempt was made to analyze 414 parents' perceptions of their experiences at the birth of their child with Down's syndrome. The interpretation of the results and the parents' comments suggest that the counseling of parents with a newborn Down's syndrome child demands tact, truthfulness, and empathetic guidance. The parents should be informed of the child's condition in a kind and sensitive manner as soon as the diagnosis of Down's syndrome has been made. Appropriate terminology should be employed, and both parents should be present when the physician tells them of their misfortune. Unconditional recommendations of institutionalization of the child with Down's syndrome should be practices of the past. The professionals' thoughtful considerations and mature counsel should assist constructively in shaping the child's future.