Journal Club
Alcohol and Health: Current Evidence
November-December 2005
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Featured Article
Combining the AUDIT questionnaire
and biochemical markers to assess
alcohol use and risk of alcohol withdrawal
in medical inpatients
Dolman JM, et al. Alcohol Alcohol. 2005;40(6):515–519.
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Study Objective
To examine whether the AUDIT* and/or
blood testing could…
• predict risk of alcohol withdrawal in
medical inpatients
*Alcohol Use Disorders Identification Test
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Study Design
• Screening with the AUDIT and blood testing
(GGT, AST, ALT, MCV)*
• 874 medical inpatients (aged 16 or older)
screened
• Incident alcohol withdrawal assessed
prospectively during hospitalization in 98
patients with a positive AUDIT score (>=8)
*Gamma glutamyltransferase, aspartate aminotransferase, alanine aminotransferase, and
mean corpuscular volume
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Assessing Validity of an
Article about Prognosis
• Are the results valid?
• What are the results?
• How can I apply the results to
patient care?
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Are the Results Valid?
• Was the sample representative?
• Were the subjects sufficiently homogeneous with
respect to prognostic risk?
• Was follow-up sufficiently complete?
• Were objective and unbiased outcome criteria
used?
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Was the sample representative?
• 267 of 1243 admissions were excluded because of
incomplete AUDIT questionnaires and lab results.
– This likely biased the sample though it is not clear in what
direction.
– So, whether the study sample was representative of all
admissions is unknown.
• Those who were confused or transferred quickly were
excluded.
• The screened sample included 874 medical inpatients,
aged 16 or older.
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Was the sample representative? (cont.)
• The sample that was monitored for withdrawal
development included only the 98 subjects
(11%) with a positive AUDIT (>=8).
– Therefore, the sample does not represent
people with an AUDIT <8 who might
develop withdrawal.
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Were the subjects sufficiently homogeneous
with respect to prognostic risk?
 Subjects were likely sufficiently homogeneous with
respect to withdrawal risk because...
 all were eligible for the study from the time of
admission.
 However, time of last drink was not reported. If
highly variable, it might have led to a heterogeneous
sample with respect to withdrawal risk.
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Was follow-up
sufficiently complete?
•
All subjects were followed through the period
of risk of developing alcohol withdrawal.
– However, the authors did not provide
details on whether any subjects were lost
to follow-up.
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Were objective and unbiased
outcome criteria used?
• Subjects with an AUDIT score of >=8 (a
positive test for an alcohol use disorder)
were monitored with the CIWA-Ar, an
objective outcome measure.
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What are the Results?
• How likely are the outcomes over time?
• How precise are the estimates of
likelihood?
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How likely are the outcomes
over time?
 Of the 98 subjects with positive AUDITs, 17 (17%)
experienced clinically significant withdrawal symptoms.
• All patients with withdrawal had positive AUDITs
(>=8; sensitivity 100%).
– However, those with AUDIT<8 were not monitored for
withdrawal using the objective outcome measure,
raising the possibility of overestimated sensitivity.
• All but 1 patient with withdrawal had abnormal blood
test results.
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How likely are the outcomes
over time? (cont.)
• Most patients without withdrawal had normal
AUDIT scores (specificity 91%).
• Although a positive AUDIT score plus any 2
abnormal blood tests had a sensitivity of 94%
and a specificity of 98%...
– fewer than half of patients with this
combination had withdrawal.
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How precise are the estimates
of likelihood?
• The authors did not provide measures
of precision.
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How Can I Apply the Results to
Patient Care?
• Were the study patients and their
management similar to those in my practice?
• Was the follow-up sufficiently long?
• Can I use the results in the management of
patients in my practice?
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Were the study patients similar
to those in my practice?
• Study patients may have been representative
of those on medicine services in general
hospitals.
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Was the follow-up
sufficiently long?
• The patients were followed until the CIWA-Ar
score was <11 for 12 hours.
– This is likely long enough that no cases of late
withdrawal were missed.
– However, longer follow-up would have reduced the
likelihood of missing any cases (e.g., 24 hours CIWAAr <8).
• The authors do not report any loss to follow-up.
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Can I use the results in the
management of patients in my practice?
Limitations to this study:
• Researchers monitored alcohol withdrawal only in
subjects with AUDIT >=8 so the study cannot draw
conclusions about those with AUDIT<8.
• A substantial number of patients were excluded because
of incomplete AUDITs or blood tests, likely biasing the
sample.
• Follow-up may not have been long enough.
• The number of patients with symptomatic withdrawal is
too small to draw firm conclusions.
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Can I use the results in the management
of patients in my practice? (cont.)
• Nonetheless, given that the AUDIT identifies
alcohol dependence, it is not surprising that it can
also predict who will have alcohol withdrawal.
• But, most patients with dependence will not have
significant withdrawal symptoms.
• Adding blood tests improves detection of those at
risk of withdrawal but may predict only 50%, at
best, of withdrawal cases.
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Can I use the results in the management
of patients in my practice? (cont.)
• Therefore, alcohol screening in the hospital is
mainly useful for…
– ruling out risk of withdrawal and
– identifying patients who might be ready for
alcohol-dependence treatment.
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