Please note: In 2003, the CTF updated its Grades of Recommendations to include an "I Recommendation" for situations where insufficient evidence exists to allow a recommendation to be made. (Formerly, these situations were captured under a "C Recommendation".) This change is not retroactive, and all "C Recommendations" made prior to 2003 have not been reevaluated in light of the new "I" recommendation grade. For a discussion of these recommendation grades, please link to the 2003 article in the Canadian Medical Association Journal here.
Primary Prevention of Fetal Alcohol SyndromePrepared by David R. Offord, MD, FRCPC, Department of Psychiatry, McMaster University, and Deborah L. Craig, MPH, Health Care Consultant, Halifax, Nova Scotia
Objective
To make recommendations for screening and counselling pregnant Canadian
women about alcohol consumption and the fetal alcohol syndrome (FAS).
This is an update of previous Canadian Task Force recommendations.
Burden of Suffering
Fetal Alcohol Syndrome (FAS) refers to a constellation of congenital
and functional anomalies occurring in children born to alcohol-abusing
women. FAS is now one of the leading causes of mental retardation.
It has been estimated that 50% of FAS victims are mentally retarded and
another 30% suffer borderline mental retardation. The term "possible
fetal alcohol effects" (FAE) has been introduced to indicate that alcohol
is being considered as one of the possible causes of a patient's birth
defects, but there are not sufficient features for a firm diagnosis of
FAS or strong evidence of an alternative diagnosis. Although the
precise incidence of FAS and FAE in Canada are not known, the incidence
of FAS is estimated to be between 1 and 2 per 1,000 live births in the
general population. The incidence of FAS is markedly increased in
the native population and in poor, inner-city neighbourhoods, as well as
rural, remote villages.
Options
Laboratory tests for excess drinking are not available. Screening tests
are the Michigan Alcoholism Screening Test, (MAST), the CAGE test, the
World Health Organization tests, the T-ACE test, the Ten Question Drinking
History (TQDH) and careful history taking. No treatment options exist for
FAS. Prevention strategies are case finding with education, counselling
and treatment for women who are identified as being at risk.
Outcomes
Sensitivities and specificities for each of the tests. FAS is a constellation
of birth anomalies that includes mental retardation, spontaneous abortion,
and many other features. Treatment outcomes include a reduction in the
number of children born with FAS and the severity of FAS. Possible fetal
alcohol effects (FAE) is considered a lesser form of FAS.
Evidence
MEDLINE was searched for 1988 - 1993 using the MeSH terms fetal alcohol
syndrome.
Values
The 13-member Task Force of experts in family medicine, geriatric medicine,
pediatrics, psychiatry and epidemiology used an evidence-based method for
evaluating the effectiveness of preventive health care interventions. Recommendations
were not based on cost-effectiveness of options. Patient preferences were
not discussed.
Background papers providing critical appraisal of the evidence and tentative recommendations prepared by the chapter author were pre-circulated to the members. Evidence for this topic was presented and deliberated upon in 1- to 2-day meetings, 2 to 3 times per year from January 1993 to March 1994. Consensus was reached on final recommendations.
Benefits, Harms, and Costs
MAST (a 25-question instrument that is time consuming to administer),
CAGE, and the World Health Organization instruments have not been tested
using pregnant women. A 2-question instrument ("Have you ever had a drinking
problem?" and "When was your last drink?") has a sensitivity of 92% to
detect alcoholism. T-ACE (a 4-question instrument) accurately identified
69% of the risk drinkers in a cohort of 971 pregnant women. The TQDH (Ten
Question Drinking History) questionnaire has been shown to be reliable
when used by obstetrical staff. Overall a positive result almost always
identifies a problem drinker, while negative results may not be accurate.
Because no treatment exists for FAS and FAE, interventions must be targeted to reduce drinking in pregnant women. 4 cohort studies show that reduced drinking reduces the rates for FAS and FAE. One showed that of 85 pregnant women, 65% were able to reduce their alcohol consumption by 50% after counselling. Of the total sample, the rate of FAS was 24% and of FAE was 26%. For the women who did not reduce their drinking, 89% of infants had 1 feature of FAE compared with 40% for those who reduced their drinking. In 2 studies of supportive counselling, 67% and 76% of drinkers reduced their drinking.
Clinicians are failing to diagnose alcoholism in at least three of four alcohol-abusing patients. Reasons include bias regarding their own abuse, inadequate training for the task, poor awareness of the problem and its consequences, time restrictions, disinterest and denial.
Warning labels on alcohol products have not been evaluated for their effect on reducing drinking behaviour.
Recommendations
Recommendation grade [A, B, C, D, E] and level of evidence
[I, II-1, II-2, II-3, III] are indicated after each recommendation. Citations
in support of individual recommendations are identified in the guideline
text.
Abstinence from drinking for all pregnant women is the official policy of both Canadian and U.S. medical organizations. In addition, the U.S. Preventive Services Task Force recommended in 1989 that all persons who use alcohol, especially pregnant women, should be encouraged to limit their consumption.
Sponsors
The Canadian Task Force on Preventive Health
Care developed this guideline with funding from Health Canada.
Selected References
Source Document
Offord D.R. & Craig D.L. Primary prevention of fetal alcohol syndrome.
In: Canadian Task Force on the Periodic Health Examination. Canadian
Guide to Clinical Preventive Health Care. Ottawa: Health Canada,
1994; 52-61.
Other