(for nonmedical reasons) and (4) illicit drugs.
Response options for each, on a five-point scale,
range from never to daily or almost daily. Used
online, the screening tool tallies the responses to
generate a score indicating the patient’s level of
risk for each type of substance and the
recommended level of intervention. It also
provides additional resources to help
practitioners intervene appropriately.^43
Laboratory Tests ..........................................................................................................
One approach to screening is to examine
laboratory values of urine, hair, blood, sweat,
saliva or carbon monoxide* to determine the
presence of nicotine,^45 alcohol^46 or other drugs.^47
Laboratory tests also can be used to look for
biological symptoms of chronic substance use.^48
For example, to assess heavy alcohol use,
doctors can look for elevated levels of the blood
proteins gamma-glutamyl transferase (GGT) or
carbohydrate-deficient transferrin (CDT).† The
size of red blood cells also increases with
prolonged heavy alcohol use.^49 The validity of
testing for these markers as a means of
identifying risky alcohol use is limited by the
fact that they are not necessarily unique to risky
drinkers.^50 For instance, increased GGT also
- Carbon monoxide breathalyzer tests used to detect
smoking.
† Heavy drinkers are defined in this context as
individuals who consume four or more drinks per
day. CDT is less accurate at determining heavy
drinking in women and adolescent populations.
can be caused by nonalcoholic liver disease. At
the same time, looking for biological markers is
more objective than using a patient’s self-
reports,^51 as it is not subject to patients’ or
examiners’ biases.Unlike tests for other diseases such as diabetes
and hypertension which can be diagnosed using
blood sugar or blood pressure measurements,
there is not a conclusive test that physicians can
conduct to determine with certainty the presence
of the disease of addiction.^52 With few
exceptions,‡ laboratory tests for nicotine, alcohol
and other drugs generally inform health care
providers of whether patients recently§ have
been using these substances rather than being
indicators of chronic use or addiction.^53Individuals, groups and organizations may be
hesitant to agree to laboratory tests for substance
use for legal, financial or personal reasons.^54
Widespread use of these tests is costly^55 and, as
with any other biological testing, the possibility‡ A liver function test that indicates an elevated level
of GGT and a complete blood count that indicates
that the red blood cells have a greater than normal
mean corpuscular volume (MCV) are evidence of
chronic heavy alcohol use.
§ With regard to smoking, high levels of nicotine or
cotinine indicate active tobacco use or use of nicotine
replacement therapy (NRT); moderate concentrations
indicate a smoker who has not had tobacco or
nicotine for two to three weeks; lower levels may
indicate a non-smoker who has been exposed to
environmental tobacco smoke; and very low to non-
detectible concentrations are found in non-smokers
who have not been exposed to environmental tobacco
smoke or a smoker who has not used tobacco or
nicotine for several weeks. An alcohol test called the
EtG can detect alcohol up to 80 hours after very
extensive drinking episodes; however, in 2006, the
Substance Abuse and Mental Health Services
Administration (SAMHSA) released an advisory
saying that the EtG test was not appropriate for
assessing alcohol use because it is highly sensitive
and unable to distinguish between alcohol absorbed
into the body from actual consumption and from
exposure to many common commercial and
household products that contain alcohol. Laboratory
tests can capture instances of other drug use for days
or weeks after use, depending on the drug.Implementing screening and brief intervention
would be a revolution in 21st century medical
practice. It would help reduce billions of
dollars annually in lost productivity, injury and
social costs associated with risky behaviors. It
would also encourage those with chronic
conditions to get the treatment they need. But
medical practices are unlikely to take action
without pressure from others who would
benefit. The question is, when will society
demand this change?^44--John C. Higgins-Biddle, PhD
Assistant Professor (Retired)
Community Medicine and Health Care
University of Connecticut Health Center