Background: Chronic Obstructive Pulmonary Disease (COPD) poses a substantial burden to Hong Kong. Smoking is the single most important risk factor for COPD. Intensive smoking cessation in COPD patients slows disease progression. Community pharmacy based smoking cessation in healthy smokers could forestall COPD onset. Each of these programs has been proven effective and cost-effective worldwide. Currently there are smoking cessation clinics in Hong Kong. But community pharmacy-based smoking cessation services are not available. The present study firstly attempts to identify the disease burden of COPD; secondly, to investigate if community pharmacy-based smoking cessation services are applicable in Hong Kong; finally, to examine if establishing the services would be cost effective in reducing the burden of COPD. Methods: A series of data analysis of mortality, morbidity and cost of hospitalization (length of stay × standard daily ward cost) was conducted to understand the burden of COPD in Hong Kong. Cost effectiveness analysis based on a Markov model evaluated smoking cessation strategies against usual care: (1) minimal counseling in smoking cessation clinics (MiniC) for COPD patients; (2) intensive counseling with pharmacotherapy in smoking cessation clinics (IC_pharm) for COPD patients; (3) community pharmacist-assisted service (CPA) for healthy smokers; (4) combination of CPA and MiniC (CPA+MiniC); (5) combination of CPA and IC_pharm (CPA+IC_Pharm). The Markov model was constructed by sex, smoking status and COPD severity to calculate the lifetime cost of COPD, cost of smoking cessation programs and QALYs. Both effectiveness and cost were discounted at 3%. Incremental cost effectiveness ratios (ICERs), i.e. cost per one QALY gain, served as the decision making rule. One way sensitivity analysis, threshold analysis and probabilistic sensitivity analysis were performed to explore the uncertainty around the parameters. Results: The overall age adjusted mortality of COPD increased from 28.8 per 100 000 in 1981 to 30.14 per 100 000 in 2008. Numbers of people aged 65+ with known COPD was projected to be over 100 000 by 2036. There were 3.8 and 7.8 years of life lost (YLL) and 3.6 and 5.6 QALYs lost due to COPD for male and female smokers respectively. Medical costs of hospitalization were estimated to be over HK$ one billion (US$132 million) in 2008. Seventy one COPD cases could be avoided in the simulated cohort by CPA. If the threshold value was HK$247 332 for one QALY gain, CPA was more cost effective than IC_Pharm, with an ICER of HK$47 717. CPA+MiniC dominated CPA. CPA+IC_Pharm was more cost effective than CPA+MiniC (ICER, HK$36 000). The probability of CPA+ IC_pharm being the most cost effective strategy was approaching 0.8 if one QALY was worth HK$96 000, and it was associated with the maximum expected QALYs if societal value for one QALY was no less than HK$80 000. Conclusion: The model-based economic evaluation demonstrated that CPA+IC_Pharm would be the most cost-effective smoking cessation strategy. Community pharmacy based (CPA) smoking cessation services could be applicable and should be proposed in Hong Kong to reduce the burden of smoking related diseases. / published_or_final_version / Public Health / Doctoral / Doctor of Philosophy

Objectives: Menthol is an organic compound synthesized or naturally obtained from peppermint or other mint oils and once added to cigarettes, is believed to have caused extra adverse health consequences (Kolawole S. Okuyemi 2004) compared with non-menthol cigarettes. This review has multi-purposes: First, to review and summarize the causes of African Americans’ high preference over menthol cigarettes; Second, to review smoking cessation studies and determine the association between menthol cigarettes and reduced quitting rates for African American smokers; Third, to gather information of evidence-based interventions for menthol cigarette smoking cessation. Methods: This article reviewed 16 journal articles through PubMed search using the following key words: menthol cigarette, smoking cessation, African American. And only one Chinese article was found by searching the key word “薄荷?” in CNKI Chinese database. Further search was done by using Google search engine and got 11 electronic articles or webpages for this topic. According to the objectives of this article, 3 journal papers were reviewed for examining the causes of African American smokers’ high preference over menthol cigarettes; 8 journal papers were reviewed for determining the association between menthol cigarettes and reduced quitting rates for African American smokers. In this section, the inclusion criteria include: age (18-65); gender (male, female); study design (cohort, cross-sectional, RCT). At last, 5 journal papers and 5 electronic resources including news were reviewed to gain an up-to-date insight for possible interventions of menthol cigarette smoking. Results: The leading causes for African American smokers’ high preference over menthol cigarettes include: like the minty/cool flavor; perceive menthol cigarette as having medicinal effects; menthol smokers’ influences from one’s social network; tobacco companies’ tailored marketing strategies. Overall, there were lower quitting rates for menthol cigarette smokers compared to non-menthol cigarette smokers at least among African American smokers. For menthol cigarettes and smoking cessation among African American smokers, 4 studies got significant results. For menthol cigarette and non-menthol cigarette smoking cessation among African American smokers: study 1 (TABLE 2), 6 weeks abstinence rate 28.3% vs. 41.5%, p=0.006; study 2 (TABLE 2), 4 weeks abstinence OR=0.32, 95% CI [0.16, 0.62], p<0.05, 6 months abstinence OR=0.48, 95% CI [0.25, 0.9], p<0.05; study 3 (TABLE 2), 6 months abstinence OR=0.23, 95% CI [0.17, 0.31], p<0.05. Study 4 (TABLE 2) compared African menthol cigarette smokers to Whites non-menthol cigarette smokers, OR=0.72, 95% CI [0.53, 0.97], p=0.031. For another 4 studies, they got non-significant results but still revealed such an association. Conclusions: Causes for African American smokers’ high preference over menthol cigarettes were identified as: tailored marketing strategies; physical properties of menthol cigarette (taste, smell); and demographic/social/psychological/cultural/attitudinal causes. There were significantly lower quitting rates for menthol cigarette smokers compared to non-menthol cigarette smokers at least among African American smokers. For menthol cigarette smoking cessation interventions, whether or not a ban on menthol would be implemented or not, comprehensive programs that include educational program, clinical menthol cigarette smoking cessation aids, taxation for price control, and smoke free and related regulations are needed. At last, China should learn experiences from the US regarding analysis of preference and possible clinical, educational, and policy interventions for menthol cigarette smoking cessation and prevention. / published_or_final_version / Medicine / Master / Master of Public Health

Background: Although perception predicts behaviours in general, it is less clear whether perceived peer smoking prevalence is associated with smoking among children. Although the harmful effects of smoking and secondhand smoke (SHS) exposure on health are well documented, little is known about the influence of SHS exposure on smoking behaviours, and the effects of smoking on perceived health. Objectives: This thesis aims to investigate the associations of (1) overestimation of peer smoking prevalence and smoking initiation, (2) self-rated health (SRH) with smoking and SHS exposure, and (3) SHS exposure at home with smoking initiation, tobacco addiction and smoking cessation, among an under-studied population of Chinese children in Hong Kong. Methods: A prospective study among primary school students (n = 2171) was conducted in 2006 (baseline) and followed up in 2008. A cross-sectional study on youth smoking (n = 36225) was conducted in 2003/4. Self-administered, anonymous questionnaires were used to collect information on socio-demographic characteristics, smoking status of the subjects, parents, siblings and other family members and SHS exposure at home and outside home. Other detailed information on smoking perceptions and behaviours were recorded among adolescents using standard questions adapted from the Global Youth Tobacco Survey. Self-reported smoking and SHS exposure were validated using hair nicotine tests. Logistic and linear regressions were used to yield adjusted odds ratio (AOR) and β-coefficients for poor SRH, smoking initiation, tobacco addiction and smoking cessation adjusting for socio-demographic characteristics and school clustering effects. Mediation of SHS exposure at home on the associations of smoking family with smoking initiation, tobacco addiction and smoking cessation were evaluated using standard mediation procedures. Results: Experimental smoking, ex-smoking and current smoking were associated with higher AORs for poor SRH than never-smoking among adolescents. Similarly, SHS exposure among never-smoking adolescents was linked to poor SRH. Overestimation of peer smoking prevalence significantly predicted smoking initiation (AOR: 1.79, 95% CI 1.03-3.13) among primary school students after 2 years, although SHS exposure did not predict overestimation. Living in smoking families and SHS exposure at home were significantly associated with smoking initiation and tobacco addiction, and hindered smoking cessation among adolescents (All p<0.05). The association between smoking family and child smoking was mediated by SHS exposure at home. Conclusions: This study provided the first evidence that overestimation of peer smoking predicted smoking initiation among young children, and smoking was associated with poor SRH among Chinese adolescents. The significant associations of SHS exposure at home with smoking behaviours should stimulate further investigations into the underlying psychosocial and physiological mechanisms. Future prospective studies with more comprehensive measurements of smoking and SHS exposure are warranted to confirm these results. Evidence-based interventions to correct misperceptions and promote smokefree homes are needed to protect children from smoking and exposure to SHS. / published_or_final_version / Community Medicine / Doctoral / Doctor of Philosophy

Introduction: Due to the high prevalence of smoking in China, exposure to second hand smoke (SHS) is a serious public health issue. However, school-aged children’s behavioral responses to SHS exposure and the associated factors are unclear. Aims: This study aims to (a) identify the sources and settings of SHS exposure among school-aged sick children and their mothers in Guangzhou, China; (b) describe the behavioral responses of those children and mothers when exposed to SHS; and (c) examine the personal and environmental factors associated with children’s responses to SHS exposure. Methods: Qualitative and quantitative methods were combined in this study. Forty-five in-depth individual interviews were conducted to investigate sick school-aged children and their mothers’ understanding of and responses to SHS. A pilot survey was used to assess the validity and reliability of the questionnaire and the feasibility of the study. A cross-sectional survey was conducted with the children and their mothers at three hospitals in Guangzhou in 2012. All sick children who were aged 6 to 12 years, able to communicate in Mandarin Chinese, and not acutely or severely ill, along with their nonsmoking mothers, were invited to join this study. Results: A total of 339 pairs of sick children and their mothers were included in the data analysis. Of these pairs, 169 (49.9%) lived with smokers. All sick children and their mothers experienced high-level SHS and third hand smoke (THS) exposure inside or outside the home. Those living with nonsmokers were also at risk of household SHS and THS exposure from guests. Most of the sick school-aged children were unaware of the dangers of SHS and THS, while the mothers had a better understanding of SHS and THS. The majority of children would adopt self-protective behaviors when exposed to SHS. The regression model for children’s behavioral responses to SHS exposure by family smokers found two significant factors: amount of social support and family smoke-free policy. Five factors were associated with children’s behavioral responses to SHS exposure by guest smokers, including boys, living with smokers, amount of social support, family members informed of the dangers of smoking, and fathers protecting children from SHS. The amount of social support, and fathers protecting children from SHS were also associated with children’s behavioral responses to SHS exposure by stranger smokers. Conclusions: To our knowledge, this is the first study to describe self-protective behavioral responses to SHS exposure among sick school-aged children in mainland China and the personal and environmental factors associated with these responses. Boys, living with smokers, and a partial smoke-free policy at home were negatively related to children’s responses to SHS exposure; however, more information about smoking, fathers’ protection from SHS, and information about the harms of smoking by family members were associated with greater self-protection among sick school-aged children. Therefore, multiple-direction interventions should be considered for children’s health promotion about smoking and SHS. / published_or_final_version / Nursing Studies / Master / Master of Philosophy

Background: Cognitive deficit is prominent in schizophrenia patients. We investigated the decision-making ability among schizophrenia patients and healthy controls based on their performance in the Iowa Gambling Task (IGT), a laboratory task developed for measuring individuals’ decision-making ability. We hypothesized that deficits in IGT performance in schizophrenia patients could be specifically ameliorated by smoking tobacco. In order to test this hypothesis, we compared smoking and non-smoking schizophrenia patients with healthy subjects, on their IGT performance. Method: Ten smokers with schizophrenia, 9 non-smokers with schizophrenia, 16 non-psychiatric non-smokers and 7 non-psychiatric smokers were administered the computerized version of IGT. The Fagerstrom Test for Nicotine Dependence (FTND) was used to assess the degree of smoking dependence of subjects and to group the smokers and non-smokers. Results: Subjects with schizophrenia performed significantly worse than non-psychiatric controls on IGT. Moreover, smokers with schizophrenia performed significantly better than non-smokers in the task. Furthermore, when comparing IGT performance of all the 4 groups, non-psychiatric non-smokers performed significantly better than psychiatric smokers in the IGT. Conclusions: Similar to the results of previous research, schizophrenia patients performed worse than controls in the IGT, suggesting impairments in risk/ reward decision-making. Cigarette smoking may partially ameliorate schizophrenia patients’ performance deficits on neurological tasks, including the IGT. These findings on schizophrenia patients are clinically important since it is believed that the ability to make timely and correct decisions can result in good treatment compliance and coping strategies thus facilitates recovery. Last but not least, further research is needed to explain how smoking tobacco facilitates cognitive functioning in schizophrenia patients. / published_or_final_version / Psychological Medicine / Master / Master of Psychological Medicine

This study examined the effects of a smoking cessation program using vouchers as reinforcers with individuals with traumatic brain injury and a history of substance abuse. The intervention was conducted at a residential facility that houses individuals with Traumatic Brain Injury (TBI). Vouchers were delivered contingent on reductions of carbon monoxide (CO) samples of 5 ppm or less across a shaping phase, and an abstinence induction phase. A standard pay phase was added at the end of the study to examine the effects of a standardized reinforcement scale with the abstinence criterion set at 8 ppm or less. Reductions in CO were not robust in the shaping and abstinence induction phase. The standard pay schedule showed some improvements in CO levels with less variability for two of the three participants.

The thesis investigated nicotine levels and their effects on hypertensive subjects and whether aspirin could be used in the treatment of hypertension to bring about not only an anti thrombotic effect but reduce the systemic blood pressure especially in those individuals who smoke cigarettes. The study, which also audits the use of aspirin, was conducted in Kuwait and so provides an insight of hypertensive patients very rarely considered in the literature The thesis begins in Chapter One with an extensive literature review which analyses the properties and problems that nicotine causes and its ability to cause hypertensive changes along with its multitude of other events. The physiological and pathological problems caused by nicotine are reviewed on the basis of its chemistry and pharmacological properties using a worldwide perspective rather than just focus on Kuwait. The second Chapter uses extensive analysis of the literature to determine the pharmacological properties of aspirin and its use in cardiovascular disease. The pharmacokinetics and therapeutic effects are presented with emphasis to its inhibitory effects on platelet activation which is central to the development of serious cardiovascular consequences such as stroke and myocardial infarction. The third Chapter returns to consider the literature in detail and why nicotine has specific effects on the cardiovascular system in terms of receptor stimulation and how aspirin may be able to reduce nicotine's cardiovascular effects and concludes with the Aims and Objectives of the thesis. The fourth Chapter investigates urinary nicotine levels in smokers from cigarettes available in Kuwait to indicate the actual levels which could be achieved by smokers in this study. This established that the levels would cause pharmacological effects demonstrating also the effects of passive smoking. The number of cigarettes smoked per day has an unpredictable effect on metabolism and urinary output of nicotine. The fifth Chapter is the major investigational section of the thesis and considers if aspirin ability to reduce cardiovascular effects, may be useful in terms of diastolic blood pressure and lipid levels in the 4 blood. The effects were suggestive that aspirin did reduce the blood pressure in hypertensive subjects but was not universal and was limited to those suffering from mild - moderate hypertension. It was determined that aspirin should be sued at the earliest age possible in these patients. The sixth Chapter involved a large scale trial of the effectiveness of aspirin treatment in hypertensive patients over a one year period in Kuwait. This used ambulatory blood pressure measurements to determine the effectiveness of daytime and nightime changes in blood pressure in patients with and without aspirin treatment. The overall conclusion was a reduced relative risk of suffering cardiovascular events in mild to moderate hypertension when aspirin (75mg/day) was administered. Specifically in smokers, aspirin lowers the systolic daytime BP and diastolic nightime BP. To support this work a comprehensive audit is provided of the use of the current use of aspirin in Kuwait hospitals.

This dissertation presents three papers applying health economics to the study of risky behaviors. The first uses data from the 1979 National Longitudinal Survey of Youth to examine the relationship between adverse events and risky behaviors among adolescents. Substance use responses to experiencing either of two adverse events--violent crime victimization or death of a non-family member one felt close to--explain 6.7 percent of first cigarette use, and 14.3 percent of first use of illegal drugs other than marijuana. Analyses of exercise, a positive coping mechanism, find shock-responses consistent with a coping-response, but not with rational, time-inconsistent, or non-rational drivers considered here. I conclude that distressing events lead to risky behaviors, with a coping response contributing to this effect.

published_or_final_version / Medical Sciences / Master / Master of Medical Sciences

published_or_final_version / Medical Sciences / Master / Master of Medical Sciences