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|Fetal alcohol syndrome|
|Classification and external resources|
Baby with fetal alcohol syndrome.
|Fetal alcohol syndrome|
|Classification and external resources|
Baby with fetal alcohol syndrome.
Fetal alcohol syndrome (FAS) is a pattern of mental and physical defects that can develop in a fetus in association with high levels of alcohol consumption during pregnancy. Alcohol crosses the placental barrier and can stunt fetal growth or weight, create distinctive facial stigmata, damage neurons and brain structures, which can result in psychological or behavioral problems, and cause other physical damage.  The main effect of FAS is permanent central nervous system damage, especially to the brain. Developing brain cells and structures can be malformed or have development interrupted by prenatal alcohol exposure; this can create an array of primary cognitive and functional disabilities (including poor memory, attention deficits, impulsive behavior, and poor cause-effect reasoning) as well as secondary disabilities (for example, predispositions to mental health problems and drug addiction). Alcohol exposure presents a risk of fetal brain damage at any point during a pregnancy, since brain development is ongoing throughout pregnancy.
As of 1987, fetal alcohol exposure was the leading known cause of intellectual disability in the Western world. In the United States and Europe, the FAS prevalence rate is estimated to be between 0.2-2 in every 1000 live births. FAS should not be confused with Fetal Alcohol Spectrum Disorders (FASD), a condition which describes a continuum of permanent birth defects caused by maternal consumption of alcohol during pregnancy, which includes FAS, as well as other disorders, and which affects about 1% of live births in the US (i.e., about 10 cases per 1000 live births). The lifetime medical and social costs of FAS are estimated to be as high as US$800,000 per child born with the disorder. Surveys found that in the United States, 10–15% of pregnant women report having recently drunk alcohol, and up to 30% drink alcohol at some point during pregnancy. The current recommendation of the Surgeon General of the United States, the British Department of Health and the Australian Government National Health and Medical Research Council is to drink no alcohol at all during pregnancy.
Growth deficiency is defined as below average height, weight or both due to prenatal alcohol exposure, and can be assessed at any point in the lifespan. Growth measurements must be adjusted for parental height, gestational age (for a premature infant), and other postnatal insults (e.g., poor nutrition), although birth height and weight are the preferred measurements. Deficiencies are documented H191 when height or weight falls at or below the 10th percentile of standardized growth charts appropriate to the patient's population.
The CDC and Canadian guidelines use the 10th percentile as a cut-off to determine growth deficiency. The "4-Digit Diagnostic Code" allows for mid-range gradations in growth deficiency (between the 3rd and 10th percentiles) and severe growth deficiency at or below the 3rd percentile. Growth deficiency (at severe, moderate, or mild levels) contributes to diagnoses of FAS and PFAS (Partial Fetal Alcohol Syndrome), but not ARND (Alcohol-Related Neurodevelopmental Disorder) or static encephalopathy.
Growth deficiency is ranked as follows by the "4-Digit Diagnostic Code:"
Several characteristic craniofacial abnormalities are often visible in individuals with FAS. The presence of FAS facial features indicates brain damage, though brain damage may also exist in their absence. FAS facial features (and most other visible, but non-diagnostic, deformities) are believed to be caused mainly during the 10th and 20th week of gestation.
Refinements in diagnostic criteria since 1975 have yielded three distinctive and diagnostically significant facial features known to result from prenatal alcohol exposure and distinguishes FAS from other disorders with partially overlapping characteristics. The three FAS facial features are:
Measurement of FAS facial features uses criteria developed by the University of Washington. The lip and philtrum are measured by a trained physician with the Lip-Philtrum Guide, a 5-point Likert Scale with representative photographs of lip and philtrum combinations ranging from normal (ranked 1) to severe (ranked 5). Palpebral fissure length (PFL) is measured in millimeters with either calipers or a clear ruler and then compared to a PFL growth chart, also developed by the University of Washington.
These distinctive facial features in a patient do strongly correlate to brain damage. Sterling Clarren of the University of Washington's Fetal Alcohol and Drug Unit told a conference in 2002:
“I have never seen anybody with this whole face who doesn't have some brain damage. In fact in studies, as the face is more FAS-like, the brain is more likely to be abnormal. The only face that you would want to counsel people or predict the future about is the full FAS face. But the risk of brain damage increases as the eyes get smaller, as the philtrum gets flatter, and the lip gets thinner. The risk goes up but not the diagnosis.“
“At one-month gestation, the top end of your body is a brain, and at the very front end of that early brain, there is tissue that has been brain tissue. It stops being brain and gets ready to be your face ... Your eyeball is also brain tissue. It's an extension of the second part of the brain. It started as brain and "popped out." So if you are going to look at parts of the brain from alcohol damage, or any kind of damage during pregnancy, eye malformations and midline facial malformations are going to be very actively related to the brain across syndromes ... and they certainly are with FAS.“
Central nervous system (CNS) damage is the primary feature of any Fetal Alcohol Spectrum Disorder (FASD) diagnosis. Prenatal exposure to alcohol — which is classified as a teratogen — can damage the brain across a continuum of gross to subtle impairments, depending on the amount, timing, and frequency of the exposure as well as genetic predispositions of the fetus and mother. While functional abnormalities are the behavioral and cognitive expressions of the FAS disability, CNS damage can be assessed in three areas: structural, neurological, and functional impairments.
All four diagnostic systems allow for assessment of CNS damage in these areas, but criteria vary. The IOM system requires structural or neurological impairment for a diagnosis of FAS. The "4-Digit Diagnostic Code" and CDC guidelines state that functional anomalies must measure at two standard deviations or worse in three or more functional domains for a diagnosis of FAS. The "4-Digit Diagnostic Code" further elaborates the degree of CNS damage according to four ranks:
Structural abnormalities of the brain are observable, physical damage to the brain or brain structures caused by prenatal alcohol exposure. Structural impairments may include microcephaly (small head size) of two or more standard deviations below the average, or other abnormalities in brain structure (e.g., agenesis of the corpus callosum, cerebellar hypoplasia).
Microcephaly is determined by comparing head circumference (often called occipitofrontal circumference, or OFC) to appropriate OFC growth charts. Other structural impairments must be observed through medical imaging techniques by a trained physician. Because imaging procedures are expensive and relatively inaccessible to most patients, diagnosis of FAS is not frequently made via structural impairments, except for microcephaly.
During the first trimester of pregnancy, alcohol interferes with the migration and organization of brain cells, which can create structural deformities or deficits within the brain. During the third trimester, damage can be caused to the hippocampus, which plays a role in memory, learning, emotion, and encoding visual and auditory information, all of which can create neurological and functional CNS impairments as well.
As of 2002, there were 25 reports of autopsies on infants known to have FAS. The first was in 1973, on an infant who died shortly after birth. The examination revealed extensive brain damage, including microcephaly, migration anomalies, callosal dysgenesis, and a massive neuroglial, leptomeningeal heterotopia covering the left hemisphere.
In 1977, Dr. Clarren described a second infant whose mother was a binge drinker. The infant died ten days after birth. The autopsy showed severe hydrocephalus, abnormal neuronal migration, and a small corpus callosum (which connects the two brain hemispheres) and cerebellum. FAS has also been linked to brainstem and cerebellar changes, agenesis of the corpus callosum and anterior commissure, neuronal migration errors, absent olfactory bulbs, meningomyelocele, and porencephaly.
When structural impairments are not observable or do not exist, neurological impairments are assessed. In the context of FAS, neurological impairments are caused by prenatal alcohol exposure which causes general neurological damage to the central nervous system (CNS) and the peripheral nervous system (PNS). A determination of a neurological problem must be made by a trained physician, and must not be due to a postnatal insult, such as a high fever, concussion, traumatic brain injury, etc.
All four diagnostic systems show virtual agreement on their criteria for CNS damage at the neurological level, and evidence of a CNS neurological impairment due to prenatal alcohol exposure will result in a diagnosis of FAS, and functional impairments are highly likely.
Neurological problems are expressed as either hard signs, or diagnosable disorders, such as epilepsy or other seizure disorders, or soft signs. Soft signs are broader, nonspecific neurological impairments, or symptoms, such as impaired fine motor skills, neurosensory hearing loss, poor gait, clumsiness, poor eye-hand coordination. Many soft signs have norm-referenced criteria, while others are determined through clinical judgment. "Clinical judgment" is only as good as the clinician, and soft signs should be assessed by either a pediatric neurologist, a pediatric neuropsychologist, or both. Those affected have mild retardation.
When structural or neurological impairments are not observed, all four diagnostic systems allow CNS damage due to prenatal alcohol exposure to be assessed in terms of functional impairments. Functional impairments are deficits, problems, delays, or abnormalities due to prenatal alcohol exposure (rather than hereditary causes or postnatal insults) in observable and measurable domains related to daily functioning, often referred to as developmental disabilities. There is no consensus on a specific pattern of functional impairments due to prenatal alcohol exposure and only CDC guidelines label developmental delays as such, so criteria vary somewhat across diagnostic systems.
The four diagnostic systems list various CNS domains that can qualify for functional impairment that can determine an FAS diagnosis:
Other conditions may commonly co-occur with FAS, stemming from prenatal alcohol exposure. However, these conditions are considered Alcohol-Related Birth Defects and not diagnostic criteria for FAS.
Prenatal alcohol exposure is the cause of fetal alcohol syndrome. A study of over 400,000 American women, all of whom had consumed alcohol during pregnancy, concluded that consumption of 15 drinks or more per week was associated with a reduction in birth weight. Though consumption of less than 15 drinks per week was not proven to cause FAS-related effects, the study authors recommend limiting consumption to no more than one standard drink per day. Also, threshold values are based upon group averages, and it is not appropriate to conclude that exposure below this threshold is necessarily ‘safe’ because of the significant individual variations in alcohol pharmacokinetics.
An analysis of seven medical research studies involving over 130,000 pregnancies found that consuming two to 14 drinks per week did not significantly increase the risk of giving birth to a child with either malformations or fetal alcohol syndrome. Pregnant women who consume approximately 144 grams of pure alcohol per day have a 30-33% chance of having a baby with FAS.
A number of studies have shown that light drinking (1-2 drinks/week) during pregnancy does not appear to pose a risk to the fetus. A study of pregnancies in eight European countries found that consuming no more than one drink per day did not appear to have any effect on fetal growth.
A follow-up of children at 18 months of age found that those from women who drank during pregnancy, even two drinks per day, scored higher in several areas of development, though in a different study, as little as one drink per day resulted in poorer spelling and reading abilities at age 6 and a linear dose-response relationship was seen between prenatal alcohol exposure and poorer arithmetic scores at the same age.
Despite intense research efforts, it has not been possible to identify a single clearcut mechanism for development of FAS or FASD. On the contrary, clinical and animal studies have identified a broad spectrum of pathways through which maternal alcohol can negatively affect the outcome of a pregnancy. Clear conclusions with universal validity are difficult to draw, since different ethnic groups show considerable genetic polymorphism for the hepatic enzymes responsible for ethanol detoxification.
Generally, fetal tissues have far less antioxidant protection than adult tissues as they express no significant quantities ADH or ALDH, and far less antioxidant enzymes like SOD, glutathion transferases or glutathion peroxidases.
Several diagnostic systems have been developed in North America:
Fetal alcohol syndrome is the only expression of FASD that has garnered consensus among experts to become an official ICD-9 and ICD-10 diagnosis. To make this diagnosis (or determine any FASD condition), a multi-disciplinary evaluation is necessary to assess each of the four key features for assessment. Generally, a trained physician will determine growth deficiency and FAS facial features. While a qualified physician may also assess central nervous system structural abnormalities and/or neurological problems, usually central nervous system damage is determined through psychological assessment. A pediatric neuropsychologist may assess all areas of functioning, including intellectual, language processing, and sensorimotor. Prenatal alcohol exposure risk may be assessed by a qualified physician or psychologist.
Alcohol intake is determined by interview of the biological mother or other family members knowledgeable of the mother's alcohol use during the pregnancy, prenatal health records, and review of available birth records, court records, chemical dependency treatment records, or other reliable sources. Exposure level is assessed as Confirmed Exposure, Unknown Exposure, and Confirmed Absence of Exposure by the IOM, CDC and Canadian diagnostic systems. The "4-Digit Diagnostic Code" further distinguishes confirmed exposure as High Risk and Some Risk:
Amount, frequency, and timing of prenatal alcohol use can dramatically impact the other three key features of FAS. While consensus exists that alcohol is a teratogen, there is no clear consensus as to what level of exposure is toxic. The CDC guidelines are silent on these elements diagnostically. The IOM and Canadian guidelines explore this further, acknowledging the importance of significant alcohol exposure from regular or heavy episodic alcohol consumption in determining, but offer no standard for diagnosis. Canadian guidelines discuss this lack of clarity and parenthetically point out that "heavy alcohol use" is defined by the National Institute on Alcohol Abuse and Alcoholism as five or more drinks per episode on five or more days during a 30 day period.
"The 4-Digit Diagnostic Code" ranking system distinguishes between levels of prenatal alcohol exposure as High Risk and Some Risk. It operationalizes high risk exposure as a blood alcohol concentration (BAC) greater than 100 mg/dL delivered at least weekly in early pregnancy. This BAC level is typically reached by a 55 kg woman drinking six to eight beers in one sitting.
For many adopted or adult patients and children in foster care, records or other reliable sources may not be available for review. Reporting alcohol use during pregnancy can also be stigmatizing to birth mothers, especially if alcohol use is ongoing. In these cases, all diagnostic systems use an unknown prenatal alcohol exposure designation. A diagnosis of FAS is still possible with an unknown exposure level if other key features of FASD are present at clinical levels.
The CDC reviewed nine syndromes that have overlapping features with FAS; however, none of these syndromes include all three FAS facial features, and none are the result of prenatal alcohol exposure:
The only certain way to prevent FAS is to simply avoid drinking alcohol during pregnancy. In the United States, the Surgeon General recommended in 1981, and again in 2005, that women abstain from alcohol use while pregnant or while planning a pregnancy, the latter to avoid damage in the earliest stages of a pregnancy, as the woman may not be aware that she has conceived. In the United States, federal legislation has required that warning labels be placed on all alcoholic beverage containers since 1988 under the Alcoholic Beverage Labeling Act.
There is no cure for FAS, because the CNS damage creates a permanent disability, but treatment is possible. Because CNS damage, symptoms, secondary disabilities, and needs vary widely by individual, there is no one treatment type that works for everyone.
Traditional behavioral interventions are predicated on learning theory, which is the basis for many parenting and professional strategies and interventions. Along with ordinary parenting styles, such strategies are frequently used by default for treating those with FAS, as the diagnoses Oppositional Defiance Disorder (ODD), Conduct Disorder, Reactive Attachment Disorder (RAD), etc. often overlap with FAS (along with ADHD), and these are sometimes thought to benefit from behavioral interventions. Frequently, a patient's poor academic achievement results in special education services, which also utilizes principles of learning theory, behavior modification, and outcome-based education.
Because the "learning system" of a patient with FAS is damaged, however, behavioral interventions are not always successful, or not successful in the long run, especially because overlapping disorders frequently stem from or are exacerbated by FAS. Kohn (1999) suggests that a rewards-punishment system in general may work somewhat in the short term but is unsuccessful in the long term because that approach fails to consider content (i.e., things "worth" learning), community (i.e., safe, cooperative learning environments), and choice (i.e., making choices versus following directions). While these elements are important to consider when working with FAS and have some usefulness in treatment, they are not alone sufficient to promote better outcomes. Kohn's minority challenge to behavioral interventions does illustrate the importance of factors beyond learning theory when trying to promote improved outcomes for FAS, and supports a more multi-model approach that can be found in varying degrees within the advocacy model and neurobehavioral approach.
Many books and handouts on FAS recommend a developmental approach, based on developmental psychology, even though most do not specify it as such and provide little theoretical background. Optimal human development generally occurs in identifiable stages (e.g., Jean Piaget's theory of cognitive development, Erik Erikson's stages of psychosocial development, John Bowlby's attachment framework, and other developmental stage theories). FAS interferes with normal development, which may cause stages to be delayed, skipped, or immaturely developed. Over time, an unaffected child can negotiate the increasing demands of life by progressing through stages of development normally, but not so for a child with FAS.
By knowing what developmental stages and tasks children follow, treatment and interventions for FAS can be tailored to helping a patient meet developmental tasks and demands successfully. If a patient is delayed in the adaptive behavior domain, for instance, then interventions would be recommended to target specific delays through additional education and practice (e.g., practiced instruction on tying shoelaces), giving reminders, or making accommodations (e.g., using slip-on shoes) to support the desired functioning level. This approach is an advance over behavioral interventions, because it takes the patient's developmental context into account while developing interventions.
The advocacy model takes the point of view that someone is needed to actively mediate between the environment and the person with FAS. Advocacy activities are conducted by an advocate (for example, a family member, friend, or case manager) and fall into three basic categories. An advocate for FAS: (1) interprets FAS and the disabilities that arise from it and explains it to the environment in which the patient operates, (2) engenders change or accommodation on behalf of the patient, and (3) assists the patient in developing and reaching attainable goals.
An understanding of the developmental framework would presumably inform and enhance the advocacy model, but advocacy also implies interventions at a systems level as well, such as educating schools, social workers, and so forth on best practices for FAS. However, several organizations devoted to FAS also use the advocacy model at a community practice level as well.
The neurobehavioral approach focuses on the neurological underpinnings from which behaviors and cognitive processes arise. It is an integrative perspective that acknowledges and encourages a multi-modal array of treatment interventions that draw from all FAS treatment approaches. The neurobehavioral approach is a serious attempt at shifting single-perspective treatment approaches into a new, coherent paradigm that addresses the complexities of problem behaviors and cognitions emanating from the CNS damage of FAS.
The neurobehavioral approach's main proponent is Diane Malbin, MSW, a recognized speaker and trainer in the FASD field, who first articulated the approach with respect to FASD and characterizes it as "Trying differently rather than trying harder." The idea to try differently refers to trying different perspectives and intervention options based on effects of the CNS damage and particular needs of the patient, rather than trying harder at implementing behavioral-based interventions that have consistently failed over time to produce improved outcomes for a patient. This approach also encourages more strength-based interventions, which allow a patient to develop positive outcomes by promoting success linked to the patient's strengths and interests.
Treating FAS at the public health and public policy levels promotes FAS prevention and diversion of public resources to assist those with FAS. It is related to the advocacy model but promoted at a systems level (rather than with the individual or family), such as developing community education and supports, state or province level prevention efforts (e.g., screening for maternal alcohol use during OB/GYN or prenatal medical care visits), or national awareness programs. Several organizations and state agencies in the U.S. are dedicated to this type of intervention.
The primary disabilities of FAS are the functional difficulties with which the child is born as a result of CNS damage due to prenatal alcohol exposure. Often, primary disabilities are mistaken as behavior problems, but the underlying CNS damage is the originating source of a functional difficulty, rather than a mental health condition, which is considered a secondary disability.
The exact mechanisms for functional problems of primary disabilities are not always fully understood, but animal studies have begun to shed light on some correlates between functional problems and brain structures damaged by prenatal alcohol exposure. Representative examples include:
Functional difficulties may result from CNS damage in more than one domain, but common functional difficulties by domain include: Note that this is not an exhaustive list of difficulties.
The secondary disabilities of FAS are those that arise later in life secondary to CNS damage. These disabilities often emerge over time due to a mismatch between the primary disabilities and environmental expectations; secondary disabilities can be ameliorated with early interventions and appropriate supportive services.
Six main secondary disabilities were identified in a University of Washington research study of 473 subjects diagnosed with FAS, PFAS (partial fetal alcohol syndrome), and ARND (alcohol-related neurodevelopmental disorder):
Malbin (2002) has identified the following areas of interests and talents as strengths that often stand out for those with FASD and should be utilized, like any strength, in treatment planning:
Anecdotal accounts of prohibitions against maternal alcohol use from Biblical, ancient Greek, and ancient Roman sources imply a historical awareness of links between maternal alcohol use and negative child outcomes. In Gaelic Scotland, the mother and nurse were not allowed to consume ale during pregnancy and breastfeeding (Martin Martin).
The earliest recorded observation of possible links between maternal alcohol use and fetal damage was made in 1899 by Dr. William Sullivan, a Liverpool prison physician who noted higher rates of stillbirth for 120 alcoholic female prisoners than their sober female relatives; he suggested the causal agent to be alcohol use. This contradicted the predominating belief at the time that heredity caused intellectual disability, poverty, and criminal behavior, which contemporary studies on the subjects usually concluded. A case study by Henry H. Goddard of the Kallikak family — popular in the early 1900s — represents this earlier perspective, though later researchers have suggested that the Kallikaks almost certainly had FAS. General studies and discussions on alcoholism throughout the mid-1900s were typically based on a heredity argument.
Prior to fetal alcohol syndrome being specifically identified and named in 1973, a few studies had noted differences between the children of mothers who used alcohol during pregnancy or breast-feeding and those who did not, but identified alcohol use as a possible contributing factor rather than heredity.
Fetal Alcohol Syndrome was named in 1973 by two dysmorphologists, Drs. Kenneth Lyons Jones and David Weyhe Smith of the University of Washington Medical School in Seattle, United States. They identified a pattern of "craniofacial, limb, and cardiovascular defects associated with prenatal onset growth deficiency and developmental delay" in eight unrelated children of three ethnic groups, all born to mothers who were alcoholics. The pattern of malformations indicated that the damage was prenatal. News of the discovery shocked some, while others were skeptical of the findings.
Dr. Paul Lemoine of Nantes, France had already published a study in a French medical journal in 1968 about children with distinctive features whose mothers were alcoholics, and in the U.S., Christy Ulleland and colleagues at the University of Washington Medical School had conducted an 18-month study in 1968–1969 documenting the risk of maternal alcohol consumption among the offspring of 11 alcoholic mothers. The Washington and Nantes findings were confirmed by a research group in Gothenburg, Sweden in 1979. Researchers in France, Sweden, and the United States were struck by how similar these children looked, though they were not related, and how they behaved in the same unfocused and hyperactive manner.
Within nine years of the Washington discovery, animal studies, including non-human monkey studies carried out at the University of Washington Primate Center by Dr. Sterling Clarren, had confirmed that alcohol was a teratogen. By 1978, 245 cases of FAS had been reported by medical researchers, and the syndrome began to be described as the most frequent known cause of intellectual disability.
While many syndromes are eponymous, i.e. named after the physician first reporting the association of symptoms, Dr. Smith named FAS after the causal agent of the symptoms. He reasoned that doing so would encourage prevention, believing that if people knew maternal alcohol consumption caused the syndrome, then abstinence during pregnancy would follow from patient education and public awareness. Nobody was aware of the full range of possible birth defects from FAS or its prevalence rate at that time, but admission of alcohol use during pregnancy can feel stigmatizing to birth mothers and complicate diagnostic efforts of a syndrome with its preventable cause in the name.
Over time, as subsequent research and clinical experience suggested that a range of effects (including physical, behavioral, and cognitive) could arise from prenatal alcohol exposure, the term Fetal Alcohol Spectrum Disorder (FASD) was developed to include FAS as well as other conditions resulting from prenatal alcohol exposure. Currently, FAS is the only expression of prenatal alcohol exposure defined by the International Statistical Classification of Diseases and Related Health Problems and assigned ICD-9 and diagnoses.
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