Study of Childhood and Congenital Myotonic Dystrophy

Here is a recent study of issues with congenital and childhood myotonic dystrophy. It seems pretty comprehensive and has a lot of good information. The summary is below followed by the link to the full study. The study does not also provide information on the link to autism or autism spectrum disorders that many of the children have. The study does not go into depth on the adult form of the disease that follows as the children age and go through puberty. But a good basic review.

“In neonates and children, DM1 predominantly affects muscle strength, cognition, respiratory, central nervous and gastrointestinal systems. Sleep disorders are often under recognized yet a significant morbidity. No effective disease modifying treatment is currently available and neonates and children with DM1 may experience severe physical and intellectual disability, which may be life limiting in the most severe forms. Management is currently supportive, incorporating regular surveillance and treatment of manifestations. Novel therapies, which target the gene and the pathogenic mechanism of abnormal splicing are emerging. Genetic counseling is critical in this autosomal dominant genetic disease with variable penetrance and potential maternal anticipation,as is assisting with family planning and undertakingcascade testing to instigate health surveillance in affected family members.”

BELOW click on hyperlink for full study in PDF form.

Childhood Myotonic dystrophy 2015

Males are worse off in Myotonic Dystrophy

A new study shows that males seem to be worse off on a number of factors when they have myotonic dystrophy. Social economic ($$$$) money issues as well as from a health standpoint they do not do as well as females. The full study can be seen here Gender and Myotonic Dystrophy

 

SUMMARY

Our study revealed the multidimensional influence of gender in DM1. First, maternal inheritance was associated with longer repeat expansions and more severe phenotype, as previously reported [5, 6]. This has been attributed to marked DNA instability in the female germ cell lineage allowing additional triplets insertion during oogenesis [43]. Such instability also results to an anticipation in case of maternal inheritance, a phenomenon corresponding to earlier onset and more severe symptoms observed in successive generations [10]. Surprisingly, and in contrast to the general assumptions, we observed that fathers transmitted up to 9% of neonatalonset (mild or severe) forms and 50% of infantile forms, especially those with lower cognitive impairment. Another unexpected observation was that only a minority of overall DM1 patients(37%) had maternal inheritance, which is most unusual for an autosomal dominant inherited disease. It probably results from increased miscarriage and perinatal lethality observed in female DM1 transmitters.

The second gender difference implied an unequal prevalence of several DM1 signs and symptoms in men and women. These differences could not be accounted for overall quantitative male-to-female disproportion in our study population (considered in all statistical analysis),or for the age and genotype differences between the two groups. Men tended to have more obvious classical DM1 symptoms, combining cognitive impairment, marked myotonia,cardiac and respiratory involvement whereas women had more extra-muscular and lateonset manifestations, less suggestive of DM1, such as cataracts, obesity, dysthyroidism, G Isymptoms and sphincter dysfunction. The most poorly symptomatic patients were women,implicating occasional hidden DM1 transmissions by undiagnosed female mutation carriers.

In practice, the sex-related differential risks of developing specific manifestations may require sex-orientated care management, which should be specifically adapted for men (at higher risk of mechanical ventilation, respiratory failure or cardiac conduction defects,which could provide more frequent hospitalization and increased mortality according PMSI database) as well as for women (at higher risk of thyroidism, obesity, sphincter dysfunction,and cataracts). This gender disproportion suggests that women could be more carefulwith their own health. This is underlined by FDM-S survey showing a similar number ofannual routine visits to the cardiologist and pneumonologist for both genders, despite male have more cardiac and respiratory involvement, which should prompt more regular medical care. Altogether, the results highlight the importance of a greater awareness about preventive medical care in DM1 male individuals.

Brain and Behavior Indicators in Myotonic Dystrophy (Autistic)

A new study from France gives some additional information for children that have myotonic Dystrophy. While not as comprehensive and the studies done in Sweden this gives good basic information on the condition. This information is very help to set up IEP goals and to know what issues for parents and professionals to expect. The study did not specifically mention Autism but many of the items described would be considered autistic in the USA
CONCLUSION: Children and adolescents with childhood DM1 have frequent diagnosis on the DSM-IV axis 1 with internalizing disorders being the most common type of disorder. They also have borderline low intelligence and frequent impairments in attention and visual-spatial construction abilities.

Behavior and learning info – summary from Netherlands

Summary of the lecture delivered at the yearly meeting organised in October 1995 by the “Werkgroep Dystrophia Myotonica” for patients and other people involved in myotonic dystrophy. This lecture was prepared by S. Umans, J Steyaert and D. Willekens of Stichting Klinische Genetica Limburg, Maastricht and Centrum voor Menselijke Erfelijkheid, U.Z. Gasthuisberg, Leuven.

INTRODUCTION

The authors distinguish different types of myotonic dystrophy. Depending on the age when muscle complaints and other associated symptoms make their first appearance, they distinguish:

1) The mild type: often cataract is found at a relative young age without occurrence of other complaints.

2) The adult type affected with myotonia at adolescent age and having increasing muscle dystrophy between the age of 20 and 40 years.

3) With the juvenile type the patient as a child already has muscle-complaints and besides has learning- and speech-defects.

4) The early infantile type distinguishes itself from the juvenile type by the presence of light symptoms from birth on. These children show similarly to the congenital type feeding problems during their first year of life, in a lighter degree than the congenital type: Development difficulties (motor development, language, speech and learning difficulties at school).

5) The congenital type: the baby clearly suffers from serious muscle-weakness, as demonstrated by lack of foetal movements, problems with swallowing and respiratory problems at birth.

DESIGN OF THE RESEARCH PROGRAMME

Among adults having the adult type of myotonic dystrophy several studies were performed regarding intelligence and occurrence of depressions. The results prove that a number of persons with myotonic dystrophy have a lower IQ than expected. On the other hand up till now little literature is available dealing with the early infantile and the juvenile type and concerning the cognitive functioning and the possible emotional difficulties.

Therefore in Leuven and Maastricht in the centres for clinical genetics a research programme was started which probes for possible behaviour, learning and emotional difficulties within a group of children and adolescents having the congenital type, the early-infantile type and the juvenile type of myotonic dystrophy.

SUBJECTS

Up till now 8 girls and 7 boys between 7 and 18 years of age, were examined. Eleven of them were in their families the first known patients suffering from myotonic dystrophy; all of them were referred to the centre for clinical genetics because of a great variety of clinical problems. The remaining 4 children were their siblings and they themselves had some type of myotonic dystrophy.

Of these 15 children 3 had the congenital type, 5 had the early-infantile type and 7 had the juvenile type.

Within the group of the early infantile type the learning difficulties often were the first signal that alarmed the parents, thus causing diagnosis of myotonic dystrophy being made during the first years in the elementary school.

The intelligence was examined by the IQ-tests WISC-R or WAIS depending on their age. These intelligence tests examine the VIQ (Verbal Intelligence Quotient, this is the intelligence for which the language is needed) and the PIQ (Performance Intelligence Quotient, thinking with use of spatial insight without need of language). It is important to know that the average IQ of the population is 100.

Possible behaviour difficulties were investigated with the CBCL (Child Behaviour CheckList); this checklist was completed by the parents. It is a checklist with several items dealing with behaviour difficulties; the degree of occurrence is counted.

Possible occurrence of depression was examined in the older children by self-report questionnaires.

Children older than 12 years of age were asked to complete the Adolescent Temperament Questionnaire. This questionnaire produces a profile of and a rough idea on the temperament.

To investigate the occurrence of certain psychiatric problems typically related to children, their parents were interviewed with the help of a structured child-psychiatric interview: the Amsterdam Child-psychiatric Interview for Children and Adolescents (ADIKA), a Dutch version of the American DICA-questionnaire.

RESEARCH-RESULTS

INTELLIGENCE

The IQ’s of the subjects were between 50 and 95, with an average figure of 80. This figure is clearly below 100, the average IQ in the population. No clear difference could be established between the verbal and the performance part of the intelligence. The difference in disadvantage of the performance IQ, as found in some studies on adult patients with myotonic dystrophy, was not again found in this study of a small group of children.

Observations during the tests showed with 10 out of the 15 subjects concentration difficulties and a brief space of attention-time. In some children also other cognitive deficits were found ( among others: defects in spatial analytical thinking, wrong thinking-strategy etc.)

CHILD BEHAVIOUR CHECKLIST CBCL

The CBCL showed behaviour difficulties in the so-called clinical range in 5 out of 15 children. Particularly withdrawal, social problems and attention-deficits were often found through this checklist. Four of these children present a child-psychiatric disorder.

With children with problems in accordance with the CBCL the internalising complaints (fearful, reserved, depressive) dominate the externalising complaints (hyperactive, oppositional, aggressive).

DEPRESSION-SCALE

Two children showed depressive complaints on the depression-scale. Both these 2 children as some others, had to face several problems during their school-career: Low results from the beginning of the elementary school, being bullied and transfer to special education. These events represent important psychosocial stress factors, which can cause depressive complaints.

TEMPERAMENT-CHECKLIST

The results on the Adolescent Temperament Questionnaire were varying and showed no specific profile.

CHILD-PSYCHIATRIC INTERVIEW

The child-psychiatric interview showed with 9 out of the 15 subjects child-psychiatric problems. This figure is substantially higher than the figure found in the population.

Five children had Attention Deficit and Hyperactivity Disorder (ADHD). This is a disorder with the symptoms: concentration and impulsivity deficit and hyperactivity. In the whole group parents often mentioned impulsive behaviour and attention deficits, even in children who did not meet all the criteria for Attention Deficit and Hyperactivity Disorder.

Two children had a separation-anxiety disorder (difficulties with loosening themselves from their parents, which manifests itself in unruly behaviour at moments of separation and continuing concern about and fear of loosing their parents or that they will be harmed.

One child had a general anxiety disorder (extreme concern, afraid of making mistakes and fear connected with events in the future and past)

One child had an adjustment disorder with depressive mood, which is a result of poor performance at school and being bullied.

CONCLUSION

For the time being it is premature to jump to conclusions based on this research in this small group. The results of the assessment of the intelligence confirm earlier research in adults with the adult type of myotonic dystrophy. This research showed that several persons with myotonic dystrophy have a lower IQ than the population- mean. Besides, some children with myotonic dystrophy have attention deficits which interfere in their functioning at school.

Striking in this pilot study is the frequent occurrence of child-psychiatric disorders. It must be mentioned that these results were obtained by means of structured interviews. At the same time most children were in their families the first known patients having myotonic dystrophy, which means that within the group there were lots of physical problems. Within this context we should interpret these results.

It has to be stated that these findings should be checked within a larger group of children and the findings should be compared with a group of children suffering from another chronic disease before we can get more decisive conclusions.

Myotonic Dystrophy Behavior and Learning Issues with Children

MYOTONIC  DYSTROPHY: BEHAVIOUR AND LEARNING DIFFICULTIES WITH CHILDREN

 

Summary of the lecture delivered at the yearly meeting organised in October 1995 by the “Werkgroep Dystrophia Myotonica” for patients and other people involved in myotonic dystrophy. This lecture was prepared by S. Umans, J Steyaert and D. Willekens of Stichting Klinische Genetica Limburg, Maastricht and Centrum voor Menselijke Erfelijkheid, U.Z. Gasthuisberg, Leuven.

INTRODUCTION

The authors distinguish different types of myotonic dystrophy. Depending on the age when muscle complaints and other associated symptoms make their first appearance, they distinguish:

 

1) The mild type: often cataract is found at a relative young age without occurrence of other complaints.

2) The adult type affected with myotonia at adolescent age and having increasing muscle dystrophy between the age of 20 and 40 years.

3) With the juvenile type the patient as a child already has muscle-complaints and besides has learning- and speech-defects.

4) The early infantile type distinguishes itself from the juvenile type by the presence of light symptoms from birth on. These children show similarly to the congenital type feeding problems during their first year of life, in a lighter degree than the congenital type: Development difficulties (motor development, language, speech and learning difficulties at school).

5) The congenital type: the baby clearly suffers from serious muscle-weakness, as demonstrated by lack of foetal movements, problems with swallowing and respiratory problems at birth.

 

DESIGN OF THE RESEARCH PROGRAMME

 

Among adults having the adult type of myotonic dystrophy several studies were performed regarding intelligence and occurrence of depressions. The results prove that a number of persons with myotonic dystrophy have a lower IQ than expected. On the other hand up till now little literature is available dealing with the early infantile and the juvenile type and concerning the cognitive functioning and the possible emotional difficulties.

Therefore in Leuven and Maastricht in the centres for clinical genetics a research programme was started which probes for possible behaviour, learning and emotional difficulties within a group of children and adolescents having the congenital type, the early-infantile type and the juvenile type of myotonic dystrophy.

 

SUBJECTS

Up till now 8 girls and 7 boys between 7 and 18 years of age, were examined. Eleven of them were in their families the first known patients suffering from myotonic dystrophy; all of them were referred to the centre for clinical genetics because of a great variety of clinical problems. The remaining 4 children were their siblings and they themselves had some type of myotonic dystrophy.

Of these 15 children 3 had the congenital type, 5 had the early-infantile type and 7 had the juvenile type.

Within the group of the early infantile type the learning difficulties often were the first signal that alarmed the parents, thus causing diagnosis of myotonic dystrophy being made during the first years in the elementary school.

The intelligence was examined by the IQ-tests WISC-R or WAIS depending on their age. These intelligence tests examine the VIQ (Verbal Intelligence Quotient, this is the intelligence for which the language is needed) and the PIQ (Performance Intelligence Quotient, thinking with use of spatial insight without need of language). It is important to know that the average IQ of the population is 100.

Possible behaviour difficulties were investigated with the CBCL (Child Behaviour CheckList); this checklist was completed by the parents. It is a checklist with several items dealing with behaviour difficulties; the degree of occurrence is counted.

Possible occurrence of depression was examined in the older children by self-report questionnaires..

Children older than 12 years of age were asked to complete the Adolescent Temperament Questionnaire. This questionnaire produces a profile of and a rough idea on the temperament.

To investigate the occurrence of certain psychiatric problems typically related to children, their parents were interviewed with the help of a structured child-psychiatric interview: the Amsterdam Child-psychiatric Interview for Children and Adolescents (ADIKA), a Dutch version of the American DICA-questionnaire.

 

RESEARCH-RESULTS

 

INTELLIGENCE

 

The IQ’s of the subjects were between 50 and 95, with an average figure of 80. This figure is clearly below 100, the average IQ in the population. No clear difference could be established between the verbal and the performance part of the intelligence. The difference in disadvantage of the performance IQ, as found in some studies on adult patients with myotonic dystrophy, was not again found in this study of a small group of children.

 

Observations during the tests showed with 10 out of the 15 subjects concentration difficulties and a brief space of attention-time. In some children also other cognitive deficits were found ( among others: defects in spatial analytical thinking, wrong thinking-strategy etc.)

 

CHILD BEHAVIOUR CHECKLIST CBCL

 

The CBCL showed behaviour difficulties in the so-called clinical range in 5 out of 15 children.  Particularly withdrawal, social problems and attention-deficits were often found through this checklist. Four of these children present a child-psychiatric disorder.

With children with problems in accordance with the CBCL the internalising complaints (fearful, reserved, depressive) dominate the externalising complaints (hyperactive, oppositional, aggressive).

GROUP
 TEST

NO.

 
 SEX
 SIBLINGS
 PRESENT

AGE
 AGE AT

ONSET
 AGE AT

DIAGNOSIS
 CTG

REPEAT

SIZE (kb)
 AFFECTED

PARENT
 CTG REPEAT

SIZE PARENT

(kb)
 
Congenital
 1
 male
   
 10
 0
 4
 3
 mother
 unknown
 
Myotonic
 2
 female
   
 16
 0
 3
 3.6
 mother
 1
 
Dystrophy
 3
 female
 1
 18
 0
 7
 3.5
 mother
 0.5
 
 
 4
 female
   
 7
 3
 7
 1.6
 mother
 unknown
 
Infantile
 5
 male
 2
 9
 1
 7
 2.2
 mother
 0.35
 
Myotonic
 6
 female
 2
 10
 2
 8
 2.1
 mother
 0.35
 
Dystrophy
 7
 male
   
 11
 1
 8
 1.2
 father
 0.7
 
 
 8
 female
   
 17
 1
 3
 1.5
 mother
 1.4
 
 
 9
 female
 3
 11
 6
 9
 2.6
 mother
 0.3
 
 
 10
 female
 4
 12
 6
 3
 1.9
 father
 2.4
 
Juvenile
 11
 male
   
 12
 7
 4
 1
 father
 0.5
 
Myotonic
 12
 female
 1
 14
 6
 4
 2
 mother
 0.5
 
Dystrophy
 13
 male
 3
 14
 7
 11
 1.5
 mother
 0.3
 
 
 14
 male
   
 16
 7
 15
 1.8
 mother
 0.4
 
 
 15
 male
 4
 16
 9
 12
 1.9
 father
 2.4
 

 

DEPRESSION-SCALE

 

Two children showed depressive complaints on the depression-scale. Both these 2 children as some others, had to face several problems during their school-career: Low results from the beginning of the elementary school, being bullied and transfer to special education. These events represent important psychosocial stress factors, which can cause depressive complaints.

 

TEMPERAMENT-CHECKLIST

The results on the Adolescent Temperament Questionnaire were varying and showed no specific profile.

 

CHILD-PSYCHIATRIC INTERVIEW

The child-psychiatric interview showed with 9 out of the 15 subjects child-psychiatric problems. This figure is substantially higher than the figure found in the population.

Five children had Attention Deficit and Hyperactivity Disorder (ADHD). This is a disorder with the symptoms: concentration and impulsivity deficit and hyperactivity. In the whole group parents often mentioned impulsive behaviour and attention deficits, even in children who did not meet all the criteria for Attention Deficit and Hyperactivity Disorder.

Two children had a separation-anxiety disorder (difficulties with loosening themselves from their parents, which manifests itself in unruly behaviour at moments of separation and continuing concern about and fear of loosing their parents or that they will be harmed.

One child had a general anxiety disorder (extreme concern, afraid of making mistakes and fear connected with events in the future and past)

One child had an adjustment disorder with depressive mood, which is a result of poor performance at school and being bullied.

 

CONCLUSION

For the time being it is premature to jump to conclusions based on this research in this small group. The results of the assessment of the intelligence confirm earlier research in  adults with the adult type of myotonic dystrophy. This research showed that several persons with myotonic dystrophy have a lower IQ  than the population- mean. Besides, some children with myotonic dystrophy have attention deficits which interfere in their functioning at school.

Striking in this pilot study is the frequent occurrence of child-psychiatric disorders. It must be mentioned that these results were obtained by means of structured interviews. At the same time most children were in their families the first known patients having myotonic dystrophy, which means that within the group there were lots of physical problems. Within this context we should interpret these results.

It has to be stated that these findings should be checked within a larger group of children and the findings should be compared with a group of children suffering from another chronic disease before we can get more decisive conclusions.