Citric Acid Aerosol
Cessation Aid*
fed
E. Rose,
We tested
Ph.D.;
and
the ability
Carol
As a Potential
S. Hickman,
M.A
the
brand,
tracheal
sensations
produced
by cigarette
satisfy smokers’ desire for cigarettes.
Fifteen
smoke and to
smokers rated
puffs)
than
control
better
than
the low tar and nicotine
puffs from
acid aerosol,
brands
their
of a citric
Smoking
brand
own
low tar and nicotine
acid aerosol
of cigarette,
cigarette,
of nicotine,
effects
ted visual,
olfactory
and taste
jects
the citric
acid aerosol
rated
citric
a
were
and air. To focus on tracheal
and pharmacologic
perceptions
to simulate
cues across
more
we equa-
conditions.
similar
cal advice
to discontinue
smoking,
one
the
survey
of comparable
editorial
literature
has
see page
comment,
shown
that
approximately
gain,
irritability,
and
these
anxiety,
difficulty
withdrawal
nicotine
craving
sleep
reduce
craving
for cigarettes
symptoms
replacement
for cigarettes
(eg,
does
can
be
proare
of the
nicotine,
not
satisfy
of
alleviated
of
by
gum),
abated
approach
to weaning
that has received
substitute
that
aspects
of
often
report
respiratory
state
from
cigarettes
little attention
thus far is to offer a safe
provides
some
of the
key
sensory
smoking.
Specifically,
enjoying
the distinctive
tract
accompanying
smoke.5
When
not enjoy
low
quently
smokers
we
tar
that
casually
ask
and nicotine
such
cigarettes
cigarette
smokers
sensations
in the
each
inhalation
of
smokers
why they do
cigarettes,
they
frelack
sufficient
“taste.”
Further
questioning,
as well as simply
having
them
hold
smoke
in the mouth
without
inhaling,
usually
reveals
that “taste”
is not important
to most smokers.
Instead,
sensations,
the
5From
Department
the
label
“taste”
seems
primarily
an impact
of Psychiatry
to encompass
other
perceived
in the traand
Biobehavioral
these
salient
that
as much
the
in smOke
by
faction
after
nicotine.
In this
stimuli
of
(IY) or nasally,
as comparable
respiratory
of
we hypoth-
sensations
in mediating
we investigated
do
amounts
Therefore,
accompanying
smoking
satisfaction.
the role of sensory
temporarily
respiratory
airways.
caused
a dramatic
attempting
rates.
tracheal
in smoke.89
each puff are critical
In a previous
study,
cues
cessation
intravenously
smokers
delivered
in smokers
increase
administered
esized
substantially.
One
results
are
some
nicotine
chewing
not appear
to be
The
acid in a fine mist
in part by the nicotine
in smoke,57
they
signals
of the subsequent
pharmacologic
of nicotine.
The
pharmacologic
effects
weight
Although
harshness.
citric
own
acid aerosol
Because
963
disturbances,
and
delivering
of citric
duced
excellent
effects
70 percent
concentrating.3
strength
a nebulizer
to or
Subjects’
chea.6
smokers
attempting
to quit fail within
the first year.’
Smokers
attempting
to quit often experience
unpleasant abstinence
symptoms
including
craving
for cigarettes,
puffs
that
suggest
nicotine
For
although
cigarette.
block of
a
equal
and may thereby
best
medi-
despite
frequent
and
best,
(after
also rated
to quit
tried to quit smoking.’
Unfortunately,
cessation
clinics
rated
satisfying
of air. It was
might
heart
milhave
of smoking
were
and more
puffs
own
a desire
to reduce
their
risk of cancer,
disease,
and chronic
obstructive
lung disease,
lions of cigarette
smokers
in the United
States
efforts
desirable,
Sub-
to their
In
more
anesthetizing
smokers’
Blockade
of respiratory
sensations
decline
in subjects’
reported
satis-
inhaling
smoke
containing
a fixed
dose
of
‘#{176}
study
we
explored
the
converse
that presentation
of smoking-related
tions
might
satisfy
smokers
even
possibility,
respiratory
sensain the absence
of
nicotine.
To reproduce
the tracheal
cues
associated
with cigarette
smoke,
we used a fine aerosol
containing
a mildly
irritating
solution
of citric acid. Citric
acid has
no known
might
smoke.
cues,
toxic
we
sensory
and
the
we
pilot
tracheal
wanted
work
have
otherwise
evaluations
Our goals
discriminate
interfered
made
suggested
perception
to focus on
blocked
subjects’
taste
citric acid has a distinctive
sitivities;
could
effects,
simulate
Because
and olfactory
lemon
flavor
with
by the
that
it
of cigarette
the tracheal
the
sen-
that
unbiased
subjects.
were twofold:
(1) to test smokers’
ability
to
between
puffs of citric
acid aerosol
and
cigarette
smoke,
and
inhalations
of each
craving
for cigarettes.
(2) to assess
substance
the ability
to quench
of a set of
smokers’
Sciences,
the
Neuropsychiatric
Institute,
School of Medicine,
University
of
California,
Los Angeles,
and Veterans
Administration
Medical
Center West Los Angeles, Brentwood
Division,
Los Angeles.
This work
was supported
by grant
DA 02665 from the National
Institute
on Drug Abuse and by the Medical
Research
Service
of the
Veterans
Administration.
Manuscript
received
February
9; revision
accepted
April
16.
Reprint
requests:
Dr Rose,
VA Medical
Center,
Brentwood
691/
B1SIN,
Los Angeles
90073
AND
MATERIALS
METHODS
Subjects
Fifteen
smokers
newspaper
(seven
men,
eight
women)
were
recruited
offering $8/hour fur participation. The mean age of subjects
was 35 years (range, 22 to 58), and on
average they had been smoking for 17 years (range, 3 to 40). Subjects’
through
advertisements
CHEST
Downloaded From: http://journal.publications.chestnet.org/pdfaccess.ashx?url=/data/journals/chest/21570/ on 06/15/2017
I 92 / 6 I DECEMBER,
1987
1005
mean
daily
cigarette
consumption
was 27 cigarettes/day
45) of nonmenthol
brands,
with
analysis)
(range,
0.7
of 1.0 mg
Fagerstrom
ence;
Tolerance
the
mean
moderate
7 (range,
of dependence
reported
not allergic
was
would
Subjects
completed
of nicotine
corresponding
of smoking
or heart
be used
10 to
(by FFC
4 to U),
ailments
which
(range,
delivery
an index
typical
no respiratory
to lidocaine
nicotine
to 1.3 mg).
Questionnaire,
score
degree
Subjects
a mean
the
and
same
mouths.
consisted
satisfaction
test.
satisfaction
test began
to abstain
and
four
scales
ranging
(Bennett
each
Model
nebulizer
that
U S-i)
(>10
)
excessive
nected
would
to
the
the
placed
the
to avoid
distal
puffed
was
end
they
total)
much”).
Subjects
that
the
(1) citric
to settle
drawn
into
of the tube
of
by the
tube
droplets
causing
in the tube
on the mouthpiece
their
for
con-
mouths.
provided
A
a draw
their
types
described
not told
the exact
brands
eliminate
would
the
aerosol.
In
cigarette,
care
was
in the filter,
which
extremely
to the
small
same
into
presented
of puffs,
through
puffing
proce-
the reservoir
sensitivities
were
respiratory
the
all
exhaling.
were
three
nature
times,
every
45 seconds
one puff of each type; the
were determined
using
blocks
after
of puffs
each
of the puffs
(64 puffs
set of 16 puffs.
to be presented
or
be included.
visual
cues
were
taken
puffs
an opaque
and
Sixteen
breaks
distinctive
any
types
screen,
Before
associated
from
and subjects
each
with
the
a mouthpiece
were
blindfolded
set of 16 puffs,
taste
and
also blunted
by having subjects rinse
for 90 seconds at a time, with a 2 percent
and by occluding
their
nostrils
with
swimmers’
the only cues on which subjects
based their ratings
and
the
possible systemic effects of nicotine or other smoke components.
In the satisfaction test, which was presented 60 minutes
after
the
completion
for eliminating
Also,
sensations
accompanying
of the discrimination
feedback
from
test,
visual,
inhalation
we used
taste,
the
same
and olfactory
the same four types of puffs were studied;
procedures
modalities.
subjects
were
not
5’
I
4.
1
ri
0
LOWCITRIC
TAR&
NICOTINE
CIGARETTE
AIR
ACID
IU)
2’
OWN
BRAND
61
I
4,
3,
fl
CITRIC
ACID
CIGARETTE
5,
w
LOW
TAR a
NICOTINE
BRAND
6
z
to create
an
according
were
squares.11
15-minute
1
I
I-.
C,
tube.
to the
acid
of air was injected
with
solution,
Thus,
z
4
2
presented
volume
Latin
mouths
C,
4
U)
delivery
the
6’
I-
3
smoke
of air were
lidocaine
noseplugs.
5
-J
nicotine
to
own
different
6
>.
and
holes
were
olfactory
solution
pharynx
tar
activated
tar
from
reservoir
of the citric
any of the ventilation
given
protruding
nebulizer
a Teflon
were
puffs
the
limit
of the four
their
To
tar
analysis;
of large
low
the Teflon
blocking
that a 35-mI
were
when
air into
in the
Puffs
with
generated
but
with
or the low
drawn
were not connected
to
Puffs
except
the
into
tank
puffs
associated
from
digram-balanced
puffs
(3) a low
aqueous
number
was allowed
aerosol
test:
dure,
these
air
brands
were
in blocks of four, with each block containing
pseudorandom
sequences
of puff delivery
inhalation.
aerosol
impact
subjects
at the
subjects
an ultrasonic
The
To reduce
When
much
to 9 (“very
a 15 percent
the aerosol
tube,
and
test
rated
of cigarette;
by a flow of compressed
seconds.
filter
at all”)
aerosol,
for 15 seconds.
preferentially
harshness,
two to three
cigarette
during
cues
puffs
quantity.
and
own
volumes
tube.
subjects
and 1 mg tar by FTC
acid
the
of cigarette,
the discrimination
acts of pulling
as a reservoir.
that
Subjects
brands
containing
was conveyed
served
during
of citric
acid was activated
it was.
we presented
0.1 mg nicotine
puff
for how
brand
0 (“not
preferred
for the
test,
of puff
a
instructed
the discrimination
customary
“harsh”
by
and
AM
were
discrimination
types
consent,
of puffs
cigarette
To deliver
before
followed
at 10
Subjects
PM.
the
from
informed
(4) air, as a control
citric
how
(2) subjects’
and nicotine
In
of several
and
types
aerosol;
at 1
it was to their
it felt,
obtaining
fullowing
acid
each
“similar”
10-point
After
period.
test
test began
lunch
for 30 minutes
lunch
to rate
“strong”
using
after
smoking
it, how
of a discrimination
discrimination
The
the
asked
“liked”
how
from
during
were
tube
subjects’
puff
and injected
nebulizer
is necessary
procedure
from
35-mi
a syringe
auditory
taken
The
with
presenting
Procedure
of a cigarette.
of smoke
cigarette,
ultrasonic
reservoir
and were
their
The
to that
puffs
nicotine
cigarettes
to a
populations.’
to numb
similar
To present
depend-
disease,
resistance
U)
U)
Ui
z
I
:1
I
3’
U)
4
2’
I
1#{149}
AIR
LOW
TAR &
NICOTINE
CIGARETTE
FIGuRE
cigarette,
1006
CITRIC
OWN
ACID
BRAND
scales
LOW
TAR &
NICOTINE
CITRIC
OWN
ACID
BRAND
CIGARETTE
1. Ratings of puffs from subjects’
and air. Rating
AIR
ranged
own brands
of cigarette,
from 0 to 9; bars denote
citric
SEM.
acid
aerosol,
a low
A Potential
Downloaded From: http://journal.publications.chestnet.org/pdfaccess.ashx?url=/data/journals/chest/21570/ on 06/15/2017
tar and
Smoking
nicotine
Cessation
Aid (Rose,
Hickman)
told
the
exact
brands
nature
would
consecutively,
types.
puffs
interpuff
by
or that
of a given
type
of ten
puffs
within
blocks
was 45 seconds,
preceded
each
block.
their
were
blocks
interval
of 10 minutes
to be presented
Ten puffs
followed
The
period
of the
be included.
own
presented
of the
other
Subjects
three
and a rest
rinsed
their
mouths with lidocaine
solution immediately
before each block of
puffs. To assess the degree of satisfaction produced by the different
types
of puffs,
subjects
each
set of puffs
on a 10-point
much
they
puffs.
Desire
using
“wanted”
a 10-point
sequence
scale.
puff
desire
reductions
to rate
scale.
Additionally,
a cigarette,
and
the
other
was presented
in craving
so much
produced
“satisfaction”
subjects
again
used
each
was
how
set of
reported
to randomize
except
the
subjects’
own
last,
because
it was expected
that
it might
have obscured
subsequent
conditions.
by any
and
to those
acid
low
less
to
the
for citric
tar and nicotine
strong
(p<Z.01)
acid
after
rated
after
ratings,
squares were
all conditions
for
for a cigarette
their
before
like
Latin
blocks
this condition
reduce
asked
a cigarette
for
of
brands;
were
the discrimination
jects’ own brands
Each
subject’s
ratings
were
averaged
across
the
of a given
type.
Planned
t tests
were
for each rating
variable
(liking,
similarity,
strength,
harshness)
to compare
the ratings
of the citric
acid aerosol
with each of the other
three
types of puffs
(Fig 1). Ratings
of similarity
to subjects’
own brands
were
significantly
than
greater
for either
cigarette
rated
as more
citric
acid
Subjects
aerosol
puffs
However,
similar
more
low tar and
less
than
strength
comparable
strength;
was rated
air and
aerosol
nicotine
own
puffs
of air (p<
(p<
subjects’
own
harshness
low tar and
nicotine
was the
citric
cigarette
from
were
than
of the
and harshness
of results
than
and
brands
brand)
puffs
than
to those of subjects’
p = .08 for harshness).
significantly
stronger
the
citric
own
nicotine
puffs
(p<01).
Ratings
of strength
what different
pattern
acid
low tar and
subjects’
(to their
significantly
of the
that
the
or the
aerosol
(p< .001).
also reported
liking
significantly
in
for
air (p<.0O1)
(p<.05).
showed
the other
of citric
acid
.01) and
.05)
but
brands
acid
those
of the
acid
own brands
(p>.2
for
The citric acid aerosol
and harsher
than both
cigarette
citric
were
significantly
for air (,p< .01) and
low tar and
nicotine
for subjects’
satisfaction
higher
were
comparable
cigarette
(p>
for
to
.8), but
own brands
was highwas also assessed
by
acid
puffs,
cigarette
craving
was
significantly
from
subjects’
own
brands
than
(p<.O5).
more
by citric
(,p< .05). The trend
for cigarette
craving
after
to be lower than after the low tar and nicotine
was not significant
(p>.2).
acid
citric acid
cigarette
DISCUSSION
Our
ated
with
results
show
with cigarette
a citric acid
the tracheal
some of the
that
the
smoke
aerosol.
with
smoking.
This
fact
that
subjects
generally
acid
can
this
better
than
conclusion
associ-
be simulated
simulation
acid,
desire
is supported
reported
control
puffs
and
nicotine
cigarette
(presented
quences).
Moreover,
after receiving
citric
sidual
sensations
of
impact
of smoke
is suffIcient
to reproduce
subjective
pleasure
and satisfaction
associ-
ated
citric
tracheal
inhalation
Moreover,
by the
liking
puffs
of air or the
of
low tar
in random
sea block of puffs of
reported
satisfaction
was higher
for a cigarette
was lower than after
and recontrol
9
(p<.OO1
for all
8
0
z
7
>
ratings
and
5
I-
for similarity,
replicated
test
was
puffs
puffs from subjects’
liking,
and strength
liking,
the
results
period.
Citric
acid
more similar
to subjects’
liked
Citric
acid
and harsher
acid
were rated
significantly
harsh
(p<.OO1)
than citric
the extent
to which
subjects
still “wanted”
a cigarette
after receiving
a set of puffs (Fig 2). After receiving
a set
w
generally
(j)<.Ol).
stronger
the
were
test
mean
.001)
from
6
discrimination
rated significantly
(p<
puffs
U
Satisfaction
harshness
than
reported
satisfaction
est (p<Ol).
Smoking
a someratings,
comparisons).
The
cigarette
and less
of satisfaction
citric
by puffs
puff
.2). However,
lower
than
after
a set of air inhalations
However,
desire
for a cigarette
was suppressed
test
four
puffs
conducted
(p>
puffs.
Ratings
of citric
RESULTS
Discrimination
test.
Ratings
of similarity
to subratings
of liking were comparable
more
aerosol
than
were
than
strength,
and
of the
prior
aerosol
was
own brands
control
puffs
of air
was also rated significantly
air puffs (p<.001).
However,
rated
significantly
lower
4
C.)
z
4
w
3
2’
111
1’
than
own brands
in terms
of similarity,
(,p<.01).
Harshness
ratings
of citric
acid and subjects’
own brands
were comparable
The low tar and nicotine
cigarette
received
higher
ratings
in this portion
of the experiment
w
4
C,
(p> .1).
slightly
than in
AIR
LOW TAR
& NICOTINE
CIGARETTE
CITRIC
ACID
AEROSOl.
OWN
BRAND
FIGURE
2. Reported
desire for cigarettes
after receiving
sets of puffs
from subjects’
own brands
of cigarette,
citric acid aerosol,
a low tar
and nicotine
cigarette,
and air. The scale for “How
much do you want
a cigarette
right now?”
ranged
from 0 to 9; bars denote
SEM.
CHEST
Downloaded From: http://journal.publications.chestnet.org/pdfaccess.ashx?url=/data/journals/chest/21570/ on 06/15/2017
/ 92 I 6 I DECEMBER.
1987
1007
presentations
of air.
Two factors
probably
account
for the higher
similarity
and liking
for subjects’
own brands
rette.
First,
the tracheobronchial
sensations
rette
smoke
were
only
imperfectly
citric acid aerosol.
It is likely that
particles
were
larger
than
those
leading
to greater
penetration
could have
deposition
into the
increased
ratings
of
of cigaof ciga-
simulated
by
the citric acid
of cigarette
in the
pharynx
smaller
bronchioles.
the relative
harshness
aerosol
smoke,
and
factor
of subjects’
the citric
been
have
could
own brands
acid aerosol.
sensed
effects
evidence
that
by
been
of the
However,
that ratings
affected
using
that
for higher
desired
there
is no convincing
of individual
puffs would
effects
airways.
acid provided
tute for subjects’
own
which
it did simulate
The
importance
smokers
has
brands
cigarette
not
been
on cigarettes.
widely
For
substi-
of cigarette,
the extent
smoke
was impressive.
simulation
awareness
of this factor may
of promising
new strategies
liance
an imperfect
of tracheal
to
example,
to
an
development
smokers’
addition
their
of the
to using
citric
of the characteristics
in our laboratory
ascorbic
acid
effective.
It is not
1008
intake
of many noxious
particulate
phase
of
acid
aerosols
of cigarette
suggest
that
and
tartaric
acid,
gases
smoke.
to simulate
also
and
In
some
prove
known
whether
the
pleasure
Hall
Pharmacological
Md:
Department
conditioned
responses
are
S. The
NA,
ed.
ton,
DC:
smokers
smoking
JR, Hatsukami
DK,
Effect of nicotine
London:
WS.
1984;
R. Smoking
Tavistock
Sensory
Harbor
JE,
attributes
Rose
nicotine
preference
Krasnegor
Washing-
83:82-87
of cigarette
report
JE,
In:
process.
and
pharmacology.
1982
Laboratory,
7 Herskovic
Md:
1979:158-85
psychology
Publications,
eds. Banbury
FG,
eds.
Bethesda,
syndrome.
Office,
and
SM,
Hall
Pickens RW, Krahn
D, Maim
S.
on the tobacco withdrawal
syn-
Psychopharmacology
Stepney
in smoking
duration
1985:102-09
as a dependence
A.
H,
J,
cessation.
Printing
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