Nicotine Dependence: Comparing Menthol and Non-Menthol
Cigarette Smokers
Qiang Li, MS
Andrew Hyland, PhD
Gary Giovino, MS, PhD
Joseph Bauer, PhD
Michael Cummings, PhD, MPH
Roswell Park Cancer Institute
2005 NCTH Meeting
Chicago, IL
May, 2005
For more info: [email protected]
Menthol in Cigarettes
• Menthol is the chief constituent of peppermint oil.
• Menthol can be applied to tobacco in three different ways: – Adding it directly to the tobacco
– Adding it to the cigarette filter
– Adding it to the cigarette packaging
• Approximately 90% of all cigarettes contain a very small amount of menthol
Menthol in Cigarettes • Menthol cigarettes contain from
0.3% to 0.7% of the tobacco weight in menthol
• A heavily menthol cigarette would have around 1% menthol.
• Menthol cigarettes account for one-fourth of the U.S. market
• Non-menthol cigarettes may contain subliminal levels (0.01-0.03%)
How Menthol in Cigarettes Might Boost Dependence?
Menthol in cigarettes
Breath holding
Airway anesthetic effects
Airway “cooling” effects
Absorption enhancement
Possible central nervous system effects
Altered puff parameter Increased
nicotineintake and
dependence
Study Objectives
• To describe the use rate of menthol cigarettes between 1988 and 2001 in a cohort of smokers
• To examine who is using menthol cigarettes
• To examine if menthol in cigarettes is associated with increased nicotine dependence
Data Source – COMMIT Study
• Community Intervention Trial for Smoking Cessation (COMMIT)
• Funded by NCI, conducted between 1988 and 1993
• A match-pair, randomized trial of 22 small to medium communities in 10 states/provinces
• ~1,000 smokers from each community identified surveyed in 1988 and followed until 1993
Data Source – COMMIT Study
• In 1988, over 10,000 heavy smokers (25+ cpd) and more than 10,000 light to moderate smokers (<25 cpd) completed a 20 minute tobacco use telephone survey.
• In 1993, over 13,000 members of this cohort were re-interviewed to assess the quit rate in each community
2001 Follow-up Survey
• With NCI funding, we tried to re-interview all the U.S. participants who completed a 1993 survey in the summer of 2001 (n=13,544).
• 7,329 subjects were tracked and completed the telephone interview.• Subjects included in this analysis were 4,488 continuous smokers
between 1988 and 1993 who finished all the three surveys, reported whether their current cigarette brand was menthol or not both in 1988, 1993 and 2001.
Outcome Variables
• Smoking cessation by 2001 – Cessation was defined as “a person who had not
smoked in the six months before the survey”
• Change of amount smoked daily from 1988 to 2001
• Change of time to first cigarette after waking
Predictor Variable
• Use of menthol cigarettes in 1988 and 1993 among continuous smokers between 1988 and 1993. It was divided into 4 categories:– Menthol in both years (M-M) (N=973)– Non-menthol in both years (N-N) (N=3,183)– Menthol in 1988 and non-menthol in 1993 (M-N)
(N=180)– Non-menthol in 1988 and menthol in 1993 (N-M)
(N=152)
Control Variables
• Gender
• Age at baseline
• Race/ethnicity
• Education
• Cigarettes smoked per day in 1993
• Time to first cigarette in the morning in 1988
• History of past serious quit attempts
• Age started smoking • Desire to stop smoking • Frequency of alcohol
consumption in 1988• Use a non-cigarette
tobacco product in 1988
• Pricing tier of cigarette smoked in 1988
• The presence of another smoker in the household in 1988
Analysis
• Logistic regression models were used to examine factors associated with use of menthol cigarettes
• Logistic regression and linear regression techniques were used to examine if use of menthol cigarettes between 1988 and 1993 was associated with change of nicotine dependence between 1993 and 2001
• Data were weighted to age, gender, race, and community to control for sttrition
• SUDAAN 8.0.2 was used to control for clustering effects
Baseline Characteristics of the Study Subjects (N=4,488)
49% 51%
36%33%
18%13%
80%
10%6%
3%
14%
22%
45%
19%
4%
16%
37%
44%
0%
25%
50%
75%
100%
Male
Female
25-3
435
-44
45-5
455
+W
hite
Black
Hispan
ic
Other
<12 1213
-15
16+ <5
5-14
15-2
425
+
Per
cent
(%
)
Gender Age (years) Race Education (years) Amount smoked (Cigarettes/day)
Flow Chart of Mentholated Cigarette Use from 1988 to 2001 among COMMIT Cohort
1988 1993 2001 # %Non-menthol Non-menthol Non-menthol 2228 37.10%Non-menthol Non-menthol Menthol 48 0.80%Non-menthol Non-menthol Quit 878 14.62%Non-menthol Menthol Non-menthol 23 0.38%Non-menthol Menthol Menthol 79 1.32%Non-menthol Menthol Quit 49 0.82%Non-menthol Quit Non-menthol 200 3.33%Non-menthol Quit Menthol 13 0.22%Non-menthol Quit Quit 973 16.20%
Menthol Non-menthol Non-menthol 100 1.67%Menthol Non-menthol Menthol 22 0.37%Menthol Non-menthol Quit 54 0.90%Menthol Menthol Non-menthol 76 1.27%Menthol Menthol Menthol 624 10.39%Menthol Menthol Quit 270 4.50%Menthol Quit Non-menthol 16 0.27%Menthol Quit Menthol 55 0.92%Menthol Quit Quit 298 4.96%
25%, 25%, and 24% of the smokers in 1988, 1993 and 2001 smoked menthol cigarettes, respectively
15% of the menthol cigarette smokers and 5% of the non-menthol cigarette smokers in 1988 switched brands by 1993
12% of the menthol cigarette smokers and 3% of the non-menthol cigarette smokers in 1993 switched brands by 2001
26% and 42% of the non-menthol cigarette smokers in 1988 quitted by 1993 and 2001, respectively
24% and 41% of the menthol cigarette smokers in 1988 quitted by 1993 and 2001, respectively
40% of the ever menthol cigarette smokers in 1988 or 1993 quitted by 2001
42% of the ever non-menthol cigarette smokers in 1988 or 1993 quitted by 2001
In 1993, Female, Younger People, African Americans, and More Educated Smokers Were More Likely to Smoke Mentholated
Cigarettes
22%
31%27%
22%28%
22%27%
32%*
19%*25%*
29%
64%*
29%*28%*28%*
0%
20%
40%
60%
80%
Overa
llM
ale
Female
25-34
35-44
45-54
55+W
hiteBlac
k
Hispan
ic
Other <12 12
13-15
16+
Perc
ent s
mok
ing
men
thol
ated
toba
cco
(%)
.
Overal l Gender Age (years) Race Educati on (years)
*: p<0.05 compared to the first category, logistic regression model controlled for gender, age, race, education, amount smoked
in 1993, time to first cigarette after waking in 1988, number of past quit attempts, age started smoking, desire to quit in 1988,
frequency of alcohol consumption in 1988, use non-cigarette tobacco products in 1988, pricing tier in 1988 and number of
other smokers in the household. Data come from the 1993 COMMIT survey (n=4,488)
Female, African American, and Less Dependent Non-menthol Cigarette Smokers Were More Likely to Switch to Menthol Cigarettes between
1988 and 1993
5% 4% 4%6%
7%
5%6%
4%5%
4% 5% 5%6%*
17%*
7%*
0.00%
5.00%
10.00%
15.00%
20.00%
25.00%
Overa
llM
ale
Female
White
Black
Hispan
ic
Other <12 12
13-15
16+ <1010-
3031-
6061+
Perc
ent s
witc
hing
men
thol
ated
cig
aret
tes
(%)
.
Overall Gender Race Education (years) Time to first cigarette after waking (min)
*: p<0.05 compared to the first category, logistic regression model controlled for gender, age, race, education, amount smoked
in 1993, time to first cigarette after waking in 1988, number of past quit attempts, age started smoking, desire to quit in 1988,
frequency of alcohol consumption in 1988, use non-cigarette tobacco products in 1988, pricing tier in 1988 and number of
other smokers in the household. Data come from the 1988 and 1993 COMMIT survey (n=6,521)
Younger, African American Menthol Cigarette Smokers Were Less Likely to Switch to Non-menthol Cigarettes between 1988 and 1993
16%17%
15%
18%17%
19%
14%15%
18%16% 16% 15%
14%
5%*
22%*
0%
10%
20%
30%
Overa
llM
ale
Female
White
Black
Hispan
ic
Other
25-34
35-44
45-54
55+ <1010-
3031-
6061+
Perc
ent s
witc
hing
pla
in c
igar
ette
s (%
) .
Overall Gender Race Age at baseline Time to first cigarette after waking (min)
*: p<0.05 compared to the first category, logistic regression model controlled for gender, age, race, education, amount smoked
in 1993, time to first cigarette after waking in 1988, number of past quit attempts, age started smoking, desire to quit in 1988,
frequency of alcohol consumption in 1988, use non-cigarette tobacco products in 1988, pricing tier in 1988 and number of
other smokers in the household. Data come from the 1988 and 1993 COMMIT survey (n=1,153)
By 2001, Quit Rates Were Similar among Smokers with Different Smoking Patterns of Menthol Cigarettes between 1988 and 1993
28%31% 31%
27%27%
32%29% 28%
31%
42%
36%
24%
0%
10%
20%
30%
40%
50%
N-N (N=3,183) N-M (N=152) M-N (N=180) M-M (N=973)
Raw
qui
t rat
e (%
)
Overall White African American
Note: N-P: 88 non-menthol, 93 non-menthol. N-M: 88 non-menthol, 93 menthol. M-N: 88 menthol, 93 non-menthol. M-M: 88 menthol, 93 menthol.
Odds Ratio for quitting in 2001 by use of mentholated cigarettes between 1988 and 1993
1.0 1.0 1.0 1.01.11.11.1
1.01.11.0
3.3
1.8
0.0
0.5
1.0
1.5
2.0
2.5
3.0
3.5
4.0
N-N N-M M-N M-M
Use of mentholated cigarettes between 1988 and 1993
Odd
s R
atio
Overall Whites African Americans
No statistically significant difference was detected in logistic regression controlled for for gender, age, race, education, amount
smoked in 1993, time to first cigarette after waking in 1988, number of past quit attempts, age started smoking, desire to quit in
1988, frequency of alcohol consumption in 1988, use non-cigarette tobacco products in 1988, pricing tier in 1988 and number of
other smokers in the household. Data come from COMMIT data between 1988 and 2001 (n=4,488)
No Consistent Pattern Was Found on the Change of Amount Smoked between 1993 and 2001 by Use of Mentholated Cigarettes between
1988 and 1993
-1.5 -1.8-1.0
-1.4 -1.5
-0.4
-3
2.2
-2.7-2.5* -2.3*
-4.8*
-6
-4
-2
0
2
4
N-N N-M M-N M-M
Use of mentholated cigarettes between 1988 and 1993
CP
D01
-CP
D93
Overall Whites African Americans
*: p<0.05 compared to N-N, linear regression model controlled for gender, age, race, education, amount smoked
in 1993, time to first cigarette after waking in 1988, number of past quit attempts, age started smoking, desire to quit in 1988,
frequency of alcohol consumption in 1988, use non-cigarette tobacco products in 1988, pricing tier in 1988 and number of
other smokers in the household. Data come from COMMIT data between 1988 and 2001 (n=3,216)
% Decreased Time to First Cigarette in the Morning from 1988 to 2001 by Use of Mentholated or Non-menthol Cigarettes in 1988 and 1993
No statistically significant difference was detected in logistic regression controlled for for gender, age, race, education, amount smoked in 1993, time to first cigarette after waking in 1988, number of past quit attempts, age started smoking, desire to quit in 1988, frequency of alcohol consumption in 1988, use non-cigarette tobacco products in 1988, pricing tier in 1988 and number of
other smokers in the household. Data come from COMMIT data between 1988 and 2001 (n=3,216)
25%27%
23%25%25%
34%
22%
26%
33%
14%
0%
21%
0%
10%
20%
30%
40%
N-N N-M M-N M-M
Use of mentholated cigarettes between 1988 and 1993
%
Overall Whites African Americans
Discussion
• In this study, no consistent pattern was found when examining the association between use of menthol cigarettes and indicators of nicotine dependence.
• This finding is consistent with our previous study using COMMIT data between 1988 and 1993.
• Menthol switchers could compensate their smoking by reducing consumption to maintain the same nicotine level, which would possibly explain the results
• Further studies are needed to confirm the findings and reconcile the conflict between theories and actual findings
Conclusion
• About a quarter of smokers in this sample smoked menthol cigarettes
• A majority of African Americans smoked menthol cigarettes
• Other factors associated with use of menthol cigarettes include female gender, higher education, and younger age
• No consistent pattern was found between use of menthol cigarettes and nicotine dependence