Evidence of Declining Nicotine Dependency in New Callers to a National Quitline

Achieving the tobacco endgame: evidence on the hardening hypothesis from repeated cross-sectional studies in New Zealand 2008-2014

INTRODUCTION

The hardening hypothesis proposes that as smoking prevalence declines the proportion of 'hardcore' or 'hardened' smokers will increase. The possible constructs of hardening include reduced motivation to quit, increased levels of addiction, increased levels of disadvantage and reduced quit rates among continuing smokers. Most previous studies have investigated only a single facet of the hypothesis. We used data from a national population monitor to test the hypothesis using measures across all four hardening constructs.

METHODS

We analysed data from a biennial population-based survey of New Zealand adults (aged 15 years+) from 2008 to 2014. Data were collected through face-to-face computer-assisted personal interviews.

RESULTS

During a period of reducing smoking prevalence, there were no statistically significant changes in indicators of hardening including the proportion of smokers who were unmotivated to quit, unable to quit despite repeated attempts or receiving state benefits or on a low income. Quit rates did not change significantly over the study period. For 2014 versus 2008, the OR for recent (within last 1-12 months) quitting was 1.14 (95% CI 0.53 to 2.46) and for sustained (within previous 13-24 months) quitting was 1.88 (95% CI 0.78 to 4.54).

CONCLUSIONS

This study provides evidence that robust tobacco control strategies that result in substantial declines in smoking prevalence are not accompanied by the hypothesised increase in 'hardcore' or 'hardened' smokers who are more addicted and less motivated and able to quit. The findings suggest that there is no need for substantial change in approach to achieve New Zealand's Smokefree 2025 goal on the grounds that the smoker population is becoming increasingly hardened.

Examining the significance of urban-rural context in tobacco quitline use: does rurality matter?

OBJECTIVES

The purpose of this study was to examine the importance of urban-rural context as a determinant of call rates to smoking cessation lines.

METHODS

This study used individual level New Zealand Quitline call data from 2005 to 2009, and 2006 New Zealand Census data on smoking to calculate Quitline call rates for smokers. Negative binomial regression examined the relationship between call rates and a sevenfold urban-rural classification, controlling for age, sex, ethnicity and deprivation.

RESULTS

We found a significant urban-rural gradient in the rate of smokers calling Quitline. Rates were highest among smokers in main-urban areas [0.09 (95 % confidence interval (CI) = 0.089, 0.091)] decreasing with successive urban-rural classifications to the lowest rate in rural/remote areas [0.036 (95 % CI = 0.03, 0.04)]. This association was not confounded by age, sex, ethnicity or deprivation.

CONCLUSIONS

Smokers in rural areas are less likely to use the New Zealand Quitline, even after controlling for confounding factors. This suggests that the national quitline is less effective in reaching rural smokers and more attention to the promotion of smoking cessation in rural communities is needed.

The hardening hypothesis: is the ability to quit decreasing due to increasing nicotine dependence? A review and commentary

The "hardening hypothesis" states tobacco control activities have mostly influenced those smokers who found it easier to quit and, thus, remaining smokers are those who are less likely to stop smoking. This paper first describes a conceptual model for hardening. Then the paper describes important methodological distinctions (quit attempts vs. ability to remain abstinent as indicators, measures of hardening per se vs. measures of causes of hardening, and dependence measures that do vs. do not include cigarettes per day (cigs/day).) After this commentary, the paper reviews data from prior reviews and new searches for studies on one type of hardening: the decreasing ability to quit due to increasing nicotine dependence. Overall, all four studies of the general population of smokers found no evidence of decreased ability to quit; however, both secondary analyses of treatment-seeking smokers found quit rates were decreasing over time. Cigs/day and time-to-first cigarette measures of dependence did not increase over time; however, two studies found that DSM-defined dependence appeared to be increasing over time. Although these data suggest hardening may be occurring in treatment seekers but not in the general population of smokers, this conclusion may be premature given the small number of data sets and indirect measures of quit success and dependence in the data sets. Future studies should include questions about quit attempts, ability to abstain, treatment use, and multi-item dependence measures.