Autism Spectrum disorder

Transcription

1 Autism Spectrum disorder Lance Lambert, DDS A.S.D Epidemiology Autism Spectrum Disorder manifests in early childhood and is characterized by abnormal social interactions, poor communication skills, and restricted repetitive and stereotyped behaviors, interests and activities. Reported rates have been rising in many countries for the past 2 decades; how much is actual increase and how much reflects changes in diagnostic definitions and practices? 1 in 88 (11.3:1000) children in US have been found to be affected, this is an average, in some communities it is lower 4.8:1000, and in some nearly twice that 21.2:1000. CDC reports a 23% rise in prevalence from 2006 to 2008 this suggests that 400,000 people in the US have ASD International Sex Worldwide prevalence is estimated to be per 10,000 Korea prevalence is reported at 2.64% Studies in Japan report much higher rates, but it is unclear if that is due to more careful evaluations or other perhaps environmental factors Again varies with region studied, in the US; 1 in 54 boys 1 in 252 girls Overall 4.6:1 boys more than girls Utah 2.7:1 Alabama 4.6:1 1

2 Etiology Etiology, Again The etiology of autism is unknown. Hypotheses include; genetic abnormalities Obstetric complications Exposure to toxins Pre and perinatal infections It is NOT linked to immunizations, as numerous studies have demonstrated. It is not linked to faulty parenting, (this was the original theory proposed in 1940 s when the disorder was first described.) Unknown! Obstetric complications Many individuals with ASD had untoward events in prenatal and perinatal periods. Which came first, obstetric complications or autism? Infection, A higher percentage of children born to women who contracted rubella during pregnancy have ASD. Prenatal exposure to medicines. E.g. valproic acid study in Denmark showed a 5 fold increase in ASD S.S.R.I. especially first trimester exposure may increase risk of ASD Neural anomalies Familial and Genetic Factors Neuroanatomic and neuroimaging studies reveal abnormalities in several regions of the brain MRI studies suggest evidence for differences in neuroanatomy and connectivity. Some of the regional differences correlate with the severity of specific symptoms Strong evidence to support familial factors influencing the risk for ASD. Risk for a second child with ASD is >18.7% Risk for 3 rd child with ASD is >50% Girls born to a family with a child with ASD is 2.8 times more likely to develop the condition,. Parental age Twin studies have demonstrated a moderate degree of genetic heritability. 33% of identical twins are concordant for autism, fraternal twins have the same risk as the siblings. A focused neurogenetic study of children with ASD yields a genetic disorder in two fifths of the children. Epidemiologic studies have shown that autism risk increases with advancing age of either parent Mothers > times greater risk (than years ) Fathers > times greater risk (than men <29 years ) Fragile X is associated with ASD 2

3 Toxic exposure This has been a popular hypothesis for the cause of Autism. A causative role has not been demonstrated One study has reported an association between exposure to organochlorine pesticides and autism How does it present? Developmental regression Developmental regression Absence of protocdeclarative pointing Abnormal reactions to environmental stimuli Abnormal social interactions Absence of symbolic play Repetitive and stereotyped behavior 13-48% of people with autism have apparently normal development until age months. They lose verbal and nonverbal communication skills It is unclear if they have an innate vulnerability Or precipitated by some environmental event. Most likely to be coincidental with other events Absence of protocdeclarative pointing Protocdeclarative pointing is the use of the index finger to indicate an item of interest to another person. Toddlers typically learn to use it to communicate their concern for an object to others The absence of this behavior is predictive of a later diagnosis of ASD Abnormal reactions to environmental stimuli Toddlers with ASD are much more interested in geometric patterns than normal development children Toddlers who prefer dynamic geometric patterns to participating in physical activities such as dance should be evaluated for ASD Parents of ASD children report unusual response to environmental stimuli, including excessive reaction or unexpected lack of reaction to sensory input. Children with ASD may display exaggerated response or rage to everyday sensory stimuli, such as bright lights or touching. 3

4 Abnormal social interactions High pain threshold Individuals with ASD may lack a display of appropriate interaction with family members Difficulties in social interactions are common May have problems making friends and understanding social intentions of other children May instead show attachments to objects not normally considered child oriented. They may want to have friends but drives others away with their behaviors. They may exhibit inappropriate friendliness, or lack of awareness of personal space. Absence of typical response to pain or physical injury may be noted If injured may display no change in behavior Sometimes parents report they are unaware of injuries until they observe the injury. (keep this in mind with dental implications) Sometimes the parent needs to ask the child if something is wrong when the child s mood changes. Language Absence of symbolic play Speech abnormalities are common Language delays Pronominal reversals are common such as saying you instead of saying I Echolalia Highly predictive of later diagnosis of autism Screening of symbolic play is a key component of routine assessment of well babies Absence of normal pretend play indicates the need for referral Odd play, may take the form of interest in parts of an object instead of the functional use of the object. i.e. child may enjoy repeatedly spinning the wheel of a toy car, instead of moving the entire car on the ground in a functional manner Body movement Self injurious behaviors Clumsiness awkward walk and abnormal motor movements are characteristic of ASD Common abnormal motor movements include hand flapping, this usually occurs when the child is happy or excited (might want to check with parents) May occur in combination with movement of the entire body, such as bouncing, and rotating. Often display motor tics Stereotyped movements: purposeless, repetitive, patterned motions, postures and sounds. Picking at skin Self biting Head punching and slapping Head banging Body punching and sapping Poking the eye, anus, and other body parts Lip chewing Removal of hair and nails Teeth grinding and chomping 4

5 Management of ASD Behavioral and related treatments have proven most effective for managing the challenges of Autism, they do not cure the disorder, rather they help the patients and their families maximize their potential, and minimize the problematic behaviors. There are many unproven dietary and medical treatments that you will encounter, we will try to understand the proposed rational for them, and evidence that that might help if there is any. Diet Food sensitivities Challenge is that many autistic children are very picky eaters, resulting in very limited and often un healthy diets A balanced diet rich in vegetables, fruits, protein and certain fats is important for good health. Avoiding pesticides is probably good advice for any one, maybe more so for these children, as they may be more sensitive to them. Many children with Autism have food sensitivities, and they have a higher than average incidence of G.I. issues. Allergies: incremental removal of foods from the diet and observation. Recurrence of symptoms when re-introduced. Patients with G.I. symptoms often have worse behavior issues. Avoiding artificial coloring, excessive sugar intake. Gluten free, Casein free A popular diet for a variety of people, not just Autistic children Most studies did not find significant improvement for the majority of children. Assuming that the diet is adequate, it is unlikely to harm a child, but is difficult to follow and expensive. Vitamin and Mineral supplements Most Americans consume less than optimal diets. An improved diet will benefit anyone Supplements are not well regulated, and excessive consumption of fat soluble vitamins can be dangerous. (A, D, E, K) 5

6 Dental management Control the environment Behavior management Pharmacologic management Prevention Know you patient Understand Use the parents for resource Ask same questions you would for developmentally delayed patients What level do they function at? Often will describe as an age Language skills, are they verbal? Receptive Language vs. Expressive How do they act with the physician? They may respond in a very exaggerated way to what you perceive as benign stimuli. They may be insensitive to pain as well. They may be fascinated by media (often very adept with computers and smart phones etc.) Understand Management tips The usually do best with routine New places people and experiences often make them very anxious, which usually makes their Autistic behaviors more extreme. Transitions are often very difficult for them. They may be very intelligent, and understand everything, but have difficulty expressing themselves, sometimes this leads to frustration, which may lead to increased Autistic behaviors. Listen to the parents. May require desensitization visits Usually respond well to being in the same room with the same assistant for each visit. They may go into sensory overload Noises Quiet room Away from busy area Sights May dim room lights Smells 6

7 More tips Often respond well to swaddling. Weighted blankets (X-ray aprons work) May need bite block or molt Watching a movie or cartoon may be helpful. Headphones with music may help. Headphones that muffle sound may help. Often very sensitive to taste and textures. Often require unflavored prophy paste May mix pumice with patients own tooth paste to give them a familiar flavor. May respond better to firm pressure than gentle touch Patients may find it soothing if you count out loud to them while you treat them. Explaining what steps you are doing before they get to leave may help first we count your teeth, then you can leave. Using media to your advantage Pharmacologic management Many Autistic patients are quite media savvy, take advantage of this If you have a web sight, a virtual tour link may be very helpful. A video of a patient having a dental procedure is frequently very helpful. A social story book is useful. Baseline cooperation What drugs are they on? What has been tried in the past? What are you doing? How stimulating? How long? Health issues? Prevention Work on oral hygiene Use fluoride Diet Hurdles Odd diets Eating habits Pouching food Goals 7