1. Nicotine and smoking: insights from the Health Survey for England
Martin Jarvis
CRUK Health Behaviour Unit
University College London

2. Why the HSE?
General Household Survey is official source for national prevalence and has excellent coverage of socio-economic factors associated with smoking. So why bother with HSE?
Crucial added ingredient is cotinine, a quantitative measure of recent smoke inhalation

3. The nicotine model: scope and caveats
Nicotine does not drive smoking behaviour in a simple way to the exclusion of other influences
Nicotine-seeking modulated by individual, family, social and societal influences
Understanding how nicotine intakes vary with these factors is the aim
Implications especially for
Product modification and harm reduction
Cessation treatments

4. Issues to consider…..… Person Product Population Passive smoking
Reliability of self-report
Preferred dose
Consumption
Occasional smoking
Product
Population
Passive smoking

5. Cotinine as a measure of nicotine intake and dependence
Main metabolite of nicotine, with t ½ ~16-20 hours
Quantitative measure of nicotine intake
Spot sample may give reasonable indication of steady state – hence of usual daily intake
Conversion factor: saliva cotinine 100ng/ml = ~6.7mg nicotine per day. Individual variation in nicotine metabolism, but estimates should be reasonably accurate when averaged across groups
Cotinine is a good indicator of the extent of nicotine dependence

6. What has cotinine got to offer?
Objective check on prevalence and cessation
Objective characterisation of extent of recent nicotine use
Indicator of extent of nicotine dependence
Measuring dependence in relation to:
Smoking history
Occasional smoking
Socio-economic status
Product smoked

7. Health Survey for England
Representative sample nationally aged 16+
Home interview + nurse visit to take biological measurements
Data collected on demographics, smoking history at interview, saliva cotinine (gas chromatography) at nurse visit
Sample with cotinine:
, smokers 2,689
, smokers 2,195

8. Self-reported smoking habits and cotinine concentrations
Reported nonsmokers- no passive
exposure
Reported nonsmokers- exposed to
Passive smoking
Self-reported smokers
Health Survey for England 1998 & 2001 combined

9. Accuracy of self-reported smoking status by age in population surveys
Never smokers
Ex-smokers
% smoking by cotinine (>14ng/ml)
16-24
7.3
20.2
25-34
1.5
9.6
35-44
1.6
6.3
45-54
0.8
4.2
55-64
0.5
4.0
65+
1.1
3.0
All ages
2.0
4.9
Self-report: no smoking, no use of nicotine replacement products
HSE 1998 & 2001 combined

10. How accurate are claims of quitting in population surveys?
Reported time
since quitting n
% smoking
by cotinine
Mean cotinine
(ng/ml)
< 6 months 89
15.7
136
6-12 months
150
24.7
172
1-2 years
152
17.8
204
2-5 years
465
7.7
111
5-9 years
662
7.1
162
10-19 years
1316
3.8
183
20+ years
2073
1.5
135
All quitters
6407
4.9
160
HSE 1998 & 2001 combined

11. Nicotine intake and questionnaire indicators of dependence

12. Relation of nicotine intake to time to first cigarette in smokers
Fine-grained and continuous relationship.
Distinction between those who light up within 5 min and those who wait for 5-15 min
HSE 1998 & 2001 combined

13. Relation of nicotine intake to time to first cigarette in smokers
Relationship of cotinine to time to first cigarette is largely independent of cigarette consumption
HSE 1998 & 2001 combined

14. Cotinine by questionnaire measure of dependence
Dependence scale:
Time to first cigarette (1-6)
Perceived difficulty of abstaining for a whole day (0-3)
Cigarette consumption (0-3)
HSE 1998 & 2001 combined

15. Variation in nicotine intake by cigarette consumption

16. Relation of cotinine to cigarette consumption in smokers
On average, cotinine increases linearly with consumption only up to cigarettes a day
HSE 1998 & 2001 combined

17. Wide variation in preferred nicotine intake between smokers
Although on average nicotine intake increases with cigarette consumption, at any level of consumption there is extremely wide variation in intake between smokers
Health Survey for England 1998 & 2001

18. Cigarette consumption and nicotine intake: do light or occasional smokers take in less per cigarette?
On average, smokers take in about 1 mg nicotine per cigarette
Lighter smokers take in more per cigarette than do heavier
Little evidence for take-it-or–leave-it smokers.
Based on equivalence 100 ng/ml
saliva cotinine = 6.7mg nicotine per day
(Benowitz)
HSE 1998 & 2001 combined

19. Product smoked and nicotine intake

20. Low yield cigarettes and smoke intake
Nicotine intake is largely independent of machine-smoked nicotine delivery
Since tar and nicotine are highly correlated in smoke, tar exposure is unlikely to differ between smokers of low- and high-yield cigarettes
HSE 1998 & 2001 combined

21. Low yield cigarettes and smoke intake. .
Nicotine yields have declined by 40% since 1980, but have smokers’ intakes reduced? . .
British Regional Heart Study baseline

22. Low yield cigarettes and smoke intake. .
On average, nicotine intakes in middle-aged men have shown no decline as tar/nicotine yields have declined by 40%
Consistent with complete compensation for nicotine
Indicates effective product modification will need to satisfy nicotine needs while reducing toxin exposure . .
British Regional Heart Study baseline , men aged 40-59
1990s data from HSE, age-matched to BRHS

23. Socio-economic variation in nicotine intake

24. Cotinine in smokers by socio-economic status
There is a marked gradient in nicotine intake by socio-economic status
Smokers in the most deprived category take in on average about one-third more nicotine
HSE 1998 & 2001 combined

25. Cotinine and dependence in smokers
The socio-economic gradient in nicotine intake among smokers is independent of the product smoked – seen both in smokers of manufactured cigarettes and own-rollers
HSE 1998 & 2001 combined

26. Variation in nicotine intake across populations

27. National differences in nicotine dependence among smokers
At any level of socio-economic deprivation, Scottish smokers have higher nicotine intakes than English smokers
Scottish Health Survey 1995, 1998
Health Survey for England 1996, 1998

28. Passive smoking: effects of partner smoking
Dose-response relationship between partner’s smoking and cotinine in nonsmoking adults
On average, dose is about 0.7% of active smokers

29. National differences in nicotine dependence among smokers
At any level of socio-economic deprivation, Scottish smokers have higher nicotine intakes than English smokers
Scottish Health Survey 1995, 1998
Health Survey for England 1996, 1998

30. Passive smoking: effects on children
Similar dose-response in children with smoking parents
Exposure in children is higher than in adults with smoking partner

31. Passive smoking and deprivation
In both adults and children, extent of exposure varies by socio-economic status

32. 10 reasons why I love the HSE
Large and representative sample
Household sampling frame
Excellent coverage of demographics
Smoking module as in GHS
Brand choice question
Time to first cigarette question
Cotinine – quantitative measure of smoke intake
Time series
Data can be combined across years
Comparison with SHS possible

33. Conclusions
Application of cotinine in smoking studies gives the opportunity for new insights into the nature and determinants of nicotine dependence
Cross-sectional studies can yield much information, but longitudinal studies are also needed to understand smoking careers
Lack of cotinine-based surveys in many countries hampers understanding
Better understanding of the contours of nicotine dependence important for developing more effective cessation treatments and for harm reduction
Policies that ignore or misunderstand the dynamics of nicotine seeking are highly likely to fail