Mortality and smoking in Hong Kong: case-control study of all adult deaths in 1998

Is Tobacco Use Associated With Risk of Recurrence and Mortality Among People With TB?: A Systematic Review and Meta-Analysis

BACKGROUND

Associations between tobacco use and poor TB treatment outcomes are well documented. However, for important outcomes such as TB recurrence or relapse and mortality during treatment, as well as for associations with smokeless tobacco (ST), the evidence is not summarized systematically.

RESEARCH QUESTION

Is tobacco use associated with risk of poor treatment outcomes among people with TB?

STUDY DESIGN AND METHODS

The MEDLINE, Embase, and Cumulative Index of Nursing and Allied Health Literature databases were searched on November 22, 2021. Epidemiologic studies reporting associations between tobacco use and at least one TB treatment outcome were eligible. Independent double-screening, extractions, and quality assessments were undertaken. Random effects meta-analyses were conducted for the two primary review outcomes (TB recurrence or relapse and mortality during treatment), and heterogeneity was explored using subgroups. Other outcomes were synthesized narratively.

RESULTS

Our searches identified 1,249 records, of which 28 were included in the meta-analyses. Based on 15 studies, higher risk of TB recurrence or relapse was found with ever using tobacco vs never using tobacco (risk ratio [RR], 1.78; 95% CI, 1.31-2.43; I2 = 85%), current tobacco use vs no tobacco use (RR, 1.95; 95% CI, 1.59-2.40; I2 = 72%), and former tobacco use vs never using tobacco (RR, 1.84; 95% CI, 1.21-2.80; I2 = 4%); heterogeneity arose from differences in study quality, design, and participant characteristics. Thirty-eight studies were identified for mortality, of which 13 reported mortality during treatment. Ever tobacco use (RR, 1.55; 95% CI, 1.32-1.81; I2 = 0%) and current tobacco use (RR, 1.51; 95% CI, 1.09-2.10; I2 = 87%) significantly increased the likelihood of mortality during treatment among people with TB compared with never using tobacco and not currently using tobacco, respectively; heterogeneity was explained largely by differences in study design. Almost all studies in the meta-analyses scored high or moderate on quality assessments. Narrative synthesis showed that tobacco use was a risk factor for other unfavorable TB treatment outcomes, as previously documented. Evidence on ST was limited, but identified studies suggested an increased risk for poor outcomes with its use compared with not using it.

INTERPRETATION

Tobacco use significantly increases the risk of TB recurrence or relapse and mortality during treatment among people with TB, highlighting the need to address tobacco use to improve TB outcomes.

TRIAL REGISTRY

PROSPERO; No.: CRD42017060821; URL: https://www.crd.york.ac.uk/prospero/.

Tobacco control in China

Chinese men consume around 40% of the world's cigarettes, causing a substantial and growing burden of tobacco-attributed death and disease. In 2005, the Chinese Government ratified the WHO Framework Convention on Tobacco Control, and tobacco control measures have since increased nationwide. To assess tobacco control progress, obstacles, and opportunities, this Review describes the long-term evolution of cigarette consumption and the associated disease burden in mainland China, and the implementation of five important tobacco control strategies advocated by WHO. These strategies covered tobacco taxation; package warnings; advertising, promotion, and sponsorship bans; public smoking bans; and cessation services. Although only 2% of women in China now smoke, half of all adult men smoke cigarettes. By the 2010s, smoking accounted for about a fifth of all adult male deaths, and this proportion is rising, following a trajectory similar to that seen in the USA 40 years earlier. The self-regulating national tobacco monopoly and its influence on policy, the country's relatively low tobacco tax, and its weak package warnings and enforcement of other tobacco control strategies all highlight challenges in tobacco control. However, these challenges can also provide opportunities to discourage smoking initiation in young women and encourage cessation in men, assisting China's long march towards better health.

Comparative evaluation of the efficacy of nicotine chewing gum and nicotine patches as nicotine replacement therapy using salivary cotinine levels as a biochemical validation measure

Background

Nicotine replacement therapy (NRT) and habit cessation counseling are considered the mainstay treatment for high nicotine dependence smokers. However, adherence to NRT is very poor. Among the NRTs, nicotine gums and nicotine patches are the most widely available. This study mainly evaluates the efficacy of nicotine gum and nicotine patches as NRT using salivary cotinine levels as a biochemical validation measure.

Materials and Methods

A cross-sectional study was conducted on 72 known smokers who were willing to receive nicotine replacement therapy for cessation of smoking habits. The sample was divided into two groups: Group 1 tobacco smokers were offered nicotine chewing gum, and group 2 tobacco smokers were offered nicotine patches. Both groups received treatment for 12 weeks. At baseline and at the end of the trial period, the saliva samples were analyzed for cotinine levels using an enzyme-linked immunosorbent assay (ELISA). The severity of smoking was assessed using the Fagerstrom Test for Nicotine Dependence (FTND).

Results

The quit rate was higher in the nicotine patch group compared with the nicotine gum group. On comparison of week one vs week twelve in the nicotine group nicotine gum group showed (CI: 18.10 to 13.83) and in the patch group (CI: 7.754 to 6.56) with P < 0.001. The pre- and post-cotinine estimation was significantly reduced for nicotine patches compared with nicotine gums, and patient compliance also yielded better results for nicotine patches.

Conclusion

This study depicts that nicotine patches were better adhered to in comparison with nicotine gums, and salivary cotinine level is an effective biochemical validation measure.

A comprehensive economic assessment of the health effects of tobacco use and implications for tobacco control in Bangladesh

BACKGROUND

Despite modest progress in reducing tobacco use, tobacco remains one of the major risk factors for non-communicable diseases in Bangladesh.

METHODS

Using disease-specific, prevalence-based, cost-of-illness approach, this research estimated the economic costs of tobacco use and exposure to secondhand smoke based on data collected from a nationally representative survey of 10 119 households in 2018.

RESULTS

The study estimated that 1.5 million adults were suffering from tobacco-attributable diseases and 61 000 children were suffering from diseases due to exposure to secondhand smoke in Bangladesh in 2018. Tobacco use caused 125 718 deaths in that year, accounting for 13.5% of all-cause deaths. The total economic cost was 305.6 billion Bangladeshi taka (BDT) (equivalent to 1.4% of gross domestic product or US$3.61 billion), including direct costs (private and public health expenditures) of BDT83.9 billion and indirect costs (productivity loss due to morbidity and premature mortality) of BDT221.7 billion. The total economic cost of tobacco more than doubled since 2004.

CONCLUSION

Tobacco use imposes a significant and increasing disease and financial burden on society. The enormous tobacco-attributable healthcare costs and productivity loss underscore the need to strengthen the implementation of tobacco control policies to curb the epidemic.

Understanding longevity in Hong Kong: a comparative study with long-living, high-income countries

BACKGROUND

Since 2013, Hong Kong has sustained the world's highest life expectancy at birth-a key indicator of population health. The reasons behind this achievement remain poorly understood but are of great relevance to both rapidly developing and high-income regions. Here, we aim to compare factors behind Hong Kong's survival advantage over long-living, high-income countries.

METHODS

Life expectancy data from 1960-2020 were obtained for 18 high-income countries in the Organisation for Economic Co-operation and Development from the Human Mortality Database and for Hong Kong from Hong Kong's Census and Statistics Department. Causes of death data from 1950-2016 were obtained from WHO's Mortality Database. We used truncated cross-sectional average length of life (TCAL) to identify the contributions to survival differences based on 263 million deaths overall. As smoking is the leading cause of premature death, we also compared smoking-attributable mortality between Hong Kong and the high-income countries.

FINDINGS

From 1979-2016, Hong Kong accumulated a substantial survival advantage over high-income countries, with a difference of 1·86 years (95% CI 1·83-1·89) for males and 2·50 years (2·47-2·53) for females. As mortality from infectious diseases declined, the main contributors to Hong Kong's survival advantage were lower mortality from cardiovascular diseases for both males (TCAL difference 1·22 years, 95% CI 1·21-1·23) and females (1·19 years, 1·18-1·21), cancer for females (0·47 years, 0·45-0·48), and transport accidents for males (0·27 years, 0·27-0·28). Among high-income populations, Hong Kong recorded the lowest cardiovascular mortality and one of the lowest cancer mortalities in women. These findings were underpinned by the lowest absolute smoking-attributable mortality in high-income regions (39·7 per 100 000 in 2016, 95% CI 34·4-45·0). Reduced smoking-attributable mortality contributed to 50·5% (0·94 years, 0·93-0·95) of Hong Kong's survival advantage over males in high-income countries and 34·8% (0·87 years, 0·87-0·88) of it in females.

INTERPRETATION

Hong Kong's leading longevity is the result of fewer diseases of poverty while suppressing the diseases of affluence. A unique combination of economic prosperity and low levels of smoking with development contributed to this achievement. As such, it offers a framework that could be replicated through deliberate policies in developing and developed populations globally.

FUNDING

Early Career Scheme (RGC ECS Grant #27602415), Research Grants Council, University Grants Committee of Hong Kong.

The methodology for assessing smoking-attributed mortality based on All Causes of Death Surveillance in Tianjin, China, 2010-2015

INTRODUCTION

The All Causes of Death Surveillance (ACDS) system was used to measure smoking-attributed mortality by inserting questions on smoking on death certificates. Smoking status information of the deceased has been routinely collected in death certificates since 2010. We describe a death registry-based case-control study using smoking and cause-of-death data for the period 2010-15.

METHODS

From 2010, three questions about the smoking status of the deceased were inserted in a revised death certificate: 1) Smoking status (current smoker, quit smoking, never smoker); 2) Number of cigarettes per day smoked; and 3) Number of years of smoking. A data-accuracy survey of 1788 telephone interviews of the family of the deceased was also conducted. Smoking habits (current/ex-smoker vs non-smoker) were compared in study cases (persons who died of lung cancer and other diseases known to be caused by smoking) and the controls (never smokers). Multivariate logistic regression analysis was conducted to estimate relative risks, RR (odds ratios) for smoking-attributed mortality, for lung cancer and all causes of death related to smoking, adjusted for 5-year interval age groups, education, marital status, and year of death.

RESULTS

During the study period (2010-15), the annual crude death reporting rates ranged from 6.5‰ to 7.0‰. The reporting rates of smoking status, smoking history and the number of cigarettes smoked daily were 95.5%, 98.6% and 98.6%, respectively. Compared to never smokers, the RR of ever smoking in males was 1.38 (95% CI: 1.33-1.43) for all causes of smoking-related deaths and 3.07 (95% CI: 2.91-3.24) for lung cancer, while in females the values were 1.46 (95% CI: 1.39-1.54) for all causes of smoking-related deaths and 4.07 (95% CI: 3.81-4.35) for lung cancer. The results in Tianjin are in accord with published results from previous studies.

CONCLUSIONS

Levels and trends in smoking attributed mortality can be measured at low cost by using the stable, complete and effective ACDS system in Tianjin.

Smoking counts: experience of implementing questions on smoking on official death certification systems

We describe our experience in several settings, following a suggestion in 1983 to add questions on the smoking status of the deceased on the UK death certificate as an effective way to monitor the evolution of the smoking epidemic. In South Africa in 1997 and in Tianjin Municipality, China, in 2010, questions about the smoking habits of the deceased were inserted on the official death certificates. In both places a system now exists to routinely collect information on smoking status in relation to causes of death. Results from two million South African and 300 000 Chinese deceased individuals have been reported, and the sample size in both places continues to grow. An unsuccessful attempt was made in 2008 to insert smoking questions on the Australian death notification forms but comments and concerns from the registrars of births, marriages and deaths have international applicability. In both China and South Africa, inserting questions on smoking on the death notification forms was not a trivial task-in each it required, as a minimum, significant commitment from several government agencies. Benefits, however, include a better local understanding of the smoking epidemic and allowing for planning and monitoring of tobacco control programmes. Documenting the varied experiences of collecting information on smoking on death notification forms is useful to those wishing to introduce such questions in their own settings. This is pertinent especially at a time when vital registration systems are being improved, with an aim to monitoring sustainable development goals.

ESTIMATING AND FORECASTING THE SMOKING-ATTRIBUTABLE MORTALITY FRACTION FOR BOTH GENDERS JOINTLY IN OVER 60 COUNTRIES

Smoking is one of the leading preventable threats to human health and a major risk factor for lung cancer, upper aero-digestive cancer, and chronic obstructive pulmonary disease. Estimating and forecasting the smoking attributable fraction (SAF) of mortality can yield insights into smoking epidemics and also provide a basis for more accurate mortality and life expectancy projection. Peto et al. (1992) proposed a method to estimate the SAF using the lung cancer mortality rate as an indicator of exposure to smoking in the population of interest. Here we use the same method to estimate the all-age SAF (ASAF) for both genders for over 60 countries. We document a strong and cross-nationally consistent pattern of the evolution of the SAF over time. We use this as the basis for a new Bayesian hierarchical model to project future male and female ASAF from over 60 countries simultaneously. This gives forecasts as well as predictive distributions that can be used to find uncertainty intervals for any quantity of interest. We assess the model using out-of-sample predictive validation, and find that it provides good forecasts and well calibrated forecast intervals, comparing favorably with other methods.

Combined nicotine patch with gum versus nicotine patch alone in smoking cessation in Hong Kong primary care clinics: a randomised controlled trial

BACKGROUND

The prevalence of daily cigarette smoking has dropped to 10% in Hong Kong (HK) in 2017, however, smoking still kills 5700 persons per year. Studies suggest that abstinence rates are higher with combined NRT than single NRT, although local data on safety and benefits of combined NRT are lacking. The aim of this study is to compare the effectiveness of combined NRT with single NRT among HK Chinese.

METHODS

This is a one-year, two-arm, parallel randomised trial. Five hundred sixty smokers, who smoked ≥10 cigarettes/day for ≥1 year, were randomized to combined and single NRT. Combined NRT group received counseling and nicotine patch & gum. Single NRT group received counselling and nicotine patch. Primary outcome was abstinence rate measured as self-reported 7-day point prevalence with CO validated at 52 weeks. Secondary outcomes included smoking abstinence rates at 4, 12, & 26 weeks. Crude odds ratio and p-value were reported from logistic regression without adjustment; for trend analysis, adjusted odds ratio (AOR) and p-value were reported from Generalized Estimating Equation (GEE) (controlling for time). All AORs were adjusted for age, sex, baseline CO and clusters.

RESULTS

Abstinence rates at 4, 12, 26 and 52 weeks were all higher in the combined NRT group (35.8, 21.9, 16.8, 20.1%) compared with the single NRT group (28, 16.8, 11.2, 14.3%). At 4 weeks, combined NRT group was more likely to quit smoking (OR 1.43, 95% CI, 1.00 to 2.05) than the single NRT group. From GEE analysis, combined NRT group had a significantly higher abstinence rate (23.6%) than the single NRT group (17.6%) across repeated measures at all-time points. Combined NRT group was more likely to quit smoking (OR 1.43, 95% CI, 1.15 to 1.77). No significant difference in the side effect profile was detected between groups.

CONCLUSIONS

Smokers given 8 weeks of combined NRT were more likely to quit smoking at 4, 12, 26 and 52 weeks compared with single NRT. Combined NRT was as well tolerated as single NRT and it should be further promoted in our community.

TRIAL REGISTRATION

NCT03836560 from ClinicalTrial.gov , 9 Feb 2019.

Economic Costs Attributable to Smoking in Hong Kong in 2011: A Possible Increase From 1998

BACKGROUND

Reduction in smoking prevalence does not necessarily reduce the costs of smoking as evidence shows in developed countries. We provide up-to-date estimates for direct and indirect costs attributable to smoking in Hong Kong in 2011 and compare with our 1998 estimates.

METHODS

We took a societal perspective to include lives and life years lost, health care costs and time lost from work in the costing. We followed guidelines on estimating costs of active smoking for those aged 35 years or above (35+) and costs due to second-hand smoking (SHS) exposure for 35+, infants aged 12 months and under and children aged 15 and below. All costs are in US dollars.

RESULTS

We estimated that 6154 deaths among 35+ in Hong Kong in 2011 were attributable to active smoking, an increase of 10% from 1998. Besides, 672 deaths were attributable to SHS exposure, that is, 10% of the total 6826 smoking-attributable deaths. The estimate of productive life lost due to deaths from active smoking by those aged under 65 years in 2011 was $166 million, an increase of about 4% over the estimate in 1998. Our conservative estimate of the annual tobacco-related disease cost in 2011 was $716 million which accounted for 0.3% of GDP. If we added the value of attributable lives lost, the annual cost would be $4.7 billion.

CONCLUSION

Despite the reduction in smoking prevalence, smoking-attributable disease still imposes a substantial economic burden on Hong Kong society. These findings support more stringent and effective tobacco control legislation, policies, and measures.

IMPLICATIONS

Current evidence shows reduction in smoking prevalence does not necessarily reduce the economic costs of smoking. Most studies in developed countries employed a societal perspective, including costs of productivity loss and indirect costs, but not all studies estimated costs associated with second-hand smoking (SHS). The present study estimated the total costs of smoking in Hong Kong including direct and indirect costs attributable to active smoking and to SHS exposure. Our study confirms the pattern of smoking epidemic in developed countries, forewarns the increasing economic burdens from tobacco, and provides East Asian countries with a prediction of their own future costs.

Smoking and Mortality in Tianjin, China: A Death Registry-Based Case-Control Study, 2010-2014

INTRODUCTION

We conducted a mortality case-control study to assess the risks of all-cause and major causes of death attributable to smoking in Tianjin from 2010 through 2014. The death registry-based study used data from The Tianjin All Causes of Death Surveillance System, which collects information routinely on smoking of the deceased in the death certificate of Tianjin Centers for Disease Control and Prevention.

METHODS

Cases (n = 154,086) and controls (n = 25,476) were deaths at 35 to 79 years from smoking-related and nonsmoking-related causes, respectively. Mortality rate ratios (RRs) for ever smokers versus never smokers, with adjustment for sex, 5-year age group, education, marital status, and year of death, and smoking-attributed fractions were calculated.

RESULTS

The RRs in men were 1.38 (95% confidence interval [CI], 1.33-1.43) for all causes and 3.07 (95% CI, 2.91-3.24) for lung cancer, and in women were 1.46 (95% CI, 1.39-1.54) and 4.07 (95% CI, 3.81-4.35). The smoking-attributed fractions for all causes and for lung cancer in men were 15.4% and 50.2%, respectively, and in women were 7.3% and 32.7%, respectively. Smoking annually caused an average of 3,756 (9.4%) deaths, mostly from lung cancer in men (47.4%) and women (66.9%). Women who started smoking before 30 had a higher RR (1.79; 95% CI, 1.63-1.97) than men who did so (1.48; 95% CI, 1.41-1.56).

CONCLUSION

Lung cancer was the main cause of smoking-induced deaths in both sexes. Tobacco use is a major cause of premature deaths in men aged 35 to 79 years. Young women must be urged to not start smoking because they could have greater risk of all-cause and lung cancer deaths than men do.

Mortality reduction from quitting smoking in Hong Kong: population-wide proportional mortality study

BACKGROUND

The effects of smoking cessation might be different in different populations. Proportional mortality studies of all deaths, relating the certified cause to retrospectively determined smoking habits, have helped assess the hazards of smoking in Hong Kong, and further analyses can help assess the effects of prolonged cessation (although not of recent cessation, as life-threatening disease can itself cause cessation, particularly in old age).

METHODS

The LIMOR study sought the certified causes of all deaths in 1998, and interviewed 81% of families at death registries to determine the decedent's smoking history. Cases were deaths from pre-defined diseases of interest (N = 15 356); controls were deaths from pre-defined non-smoking-related diseases (N = 5023). Case vs control odds ratios for ex-smokers vs smokers were calculated by age-, sex- and education-standardized logistic regression. These are described as mortality rate ratios (RRs), with a group-specific confidence interval (CI).

RESULTS

For the aggregate of all deaths from any of the diseases of interest at ages 35-69 years, the RRs for current smoking, quitting 0-4, 5-9 or 10+ years ago and never-smoking were, respectively, RR = 1 (95% CI 0.86-1.17), 0.91 (0.73-1.14), 0.71 (0.49-1.02), 0.66 (0.50-0.87) and 0.43 (0.37-0.48). Younger age of quitting (25-44 or 45-64) appeared to be associated with greater protection: RR = 0.58 (0.38-0.88) and 0.71 (0.54-0.93), respectively. These patterns were less clear at older ages, particularly for death from emphysema.

CONCLUSIONS

Longer durations of smoking cessation are associated with progressively lower mortality rates from the diseases of interest. For sustainable monitoring of tobacco-attributed mortality, approximate years since last smoked should be recorded during death registration.

Living with Smoker(s) and Smoking Cessation in Chinese Adult Smokers: Cross-Sectional and Prospective Evidence from Hong Kong Population Health Survey

Background: Results on the environmental influence on unassisted quitting are scarce. We investigated the associations of living with smoker(s) with quitting in Chinese adult smokers. Methods: We examined both cross-sectional and prospective data in the Hong Kong Population Health Survey recruited participants in 2003/04, and followed up to 2006. Unconditional logistic regression yielded adjusted odds ratios (AORs) of (i) planning to quit, (ii) ex-smoking (cross-sectional), and quitting (prospective) for living with smoker(s). 1679 ever smokers aged 18+ years at baseline, and 323 of them who were successfully followed-up were included in the cross-sectional, and prospective analysis. Results: At baseline, living with smoker(s) was significantly associated with lower odds of planning to quit in current smokers (AOR 0.41, 95% CI 0.25–0.68), and lower odds of ex-smoking (AOR 0.45, 95% CI 0.34–0.58), particularly if the smoker(s) smoked inside home (AOR 0.35, 95% CI 0.26–0.47). Prospectively, living with smoker(s) non-significantly predicted lower odds of new quitting (AOR 0.48, 95% CI 0.13–1.78). Conclusions: Our study has provided the first evidence in a Chinese general population that living with smoker(s) is an important barrier against smoking cessation. To boost quit rate in nonusers of smoking cessation services, smoking at home should be banned, especially for populations living in crowed urban environments that are typical of economically developed cities in China.

Clinical response of tuberculosis patients, a prospective cohort study

Clinical response means a response to drug intake that can be detected and appreciated by a change in signs and symptoms. The objectives of this study were to assess time to clinical response, the incidence density for clinical response and determinants of clinical response of tuberculosis (TB) patients in the intensive phases of TB treatment. Prospective cohort study design was implemented. The target population for this study was all patients following the directly observed therapy. Baseline data has been collected during the start of the directly observed TB treatment strategy. We have been collected updated data after the seven days of the baseline data collection, then after every seven days updated data has been collected from each pulmonary and extra pulmonary TB patients. Kaplan Meier curve was used to estimate time to clinical response. Incidence density using person days was used to estimate incidence of clinical response. Cox proportional hazard model was used to identify the predictors of clinical responses. A total of 1608 TB patients were included with a response rate at 99.5%. The mean age of the respondents was 24.5 years [standard deviation (SD) 14.34 years]. The incidence density for clinical response was 1429/38529 person days. One fourth of the TB patients showed clinical response at day 14, 25% of at day 21 and 75% o at day 31. Predictors of clinical response for TB patients includes: age (AHR 1.007 [95% CI 1.003-1.011]), type of TB (AOR 2.3[95% CI 2.04-2.59]), Previous history of TB (AHR 0.18 [95% CI 0.11-0 .30]), Intestinal parasitic infection (AOR 0.22[95% CI 0.19-0.26]), hemoglobin (AOR 2.35 [95% CI 2.18-2.54]), weight gain (AOR 1.11 [95% CI 1.05-1.17]), Micronutrient supplementation (AOR 9.71 [95% CI 8.28-11.38]), male sex (AOR 0.87 [95% CI 0.79-0.97]).The clinical responses for extra-pulmonary TB patients were slower than pulmonary TB. Deworming and micronutrient supplementation should be considered as the additional TB treatment strategy for TB patients.

Promoting Smoking Cessation Among the Elderly

Purpose: To assess the predictors of smoking cessation and intention to quit among the Chinese elderly smokers. Design: A cross-sectional survey of elderly smokers. Setting: Shamsuipo district, Hong Kong. Subject: A total of 1,318 elderly were interviewed (response rate = 83%). Measures: A structured questionnaire was used for data collection. The questionnaire sought information on the subject's sociodemographic background and smoking habits. The predictors for successful quitting and intention to quit were assessed by chi-square tests and multiple logistic regression. Results: Of the respondents, 20.2% were current smokers, 25.4% were ex-smokers, and 54.4% were never smokers. Of the smoker (current and ex-smokers) respondents, 55.7% (335/601) had successfully quit at the time of enumeration. The predictors of quitting were living with others, receiving assistance for mobility, being nondrinkers, smoking for shorter duration, and smoking more cigarettes per day. Having health problems in the past, smoking for shorter duration, and smoking fewer cigarettes per day were predictors of intention to quit smoking. Conclusion:The study identified several predictors of successful quitting that could help improve the provision of current smoking cessation services. Population-based smoking cessation programs, especially those targeted to elderly, should take these predictors into consideration in the design of interventions.

Brief advice and active referral for smoking cessation services among community smokers: a study protocol for randomized controlled trial

Background

Most smokers do not use smoking cessation (SC) services although it increases successful quits. Passive referral providing SC information to smokers is commonly used in SC studies. Little was known about active referral in the community setting. This study aims to motivate community smokers to quit by brief SC advice using a validated AWARD model (Ask, Warn, Advise, Refer and Do-it-again) that adjunct with active referral of smokers to various SC services in Hong Kong.

Methods/Design

This is a single-blinded, parallel three-armed cluster randomized controlled trial (RCT) with two treatment groups of (1) brief SC advice using the AWARD model, active referral to SC services plus a referral card and a health warning leaflet (active referral group) and (2) brief SC advice using AWARD model and health warning leaflet (brief advice group) and a control group receives general very brief advice with a self-help booklet. A total of 1291 smokers will be recruited from 66 clusters (recruitment sessions) with 22 will be allocated to each of the two intervention and one control groups. SC ambassadors will be trained for delivering the interventions and conducting telephone follow-up. The primary outcomes are self-reported 7-days point prevalence (PP) abstinence at 3 and 6 months follow-up. Intention-to-treat principle and multi-level regressions will be used for data analysis.

Discussion

This is the first RCT on assessing a model combining brief advice and active referral to SC services among community smokers. The results will inform the practices of SC services and intervention studies.

Trial registration

NCT02539875 (ClinicalTrials.gov registry; registered retrospectively on 22 July 2015)

Contrasting male and female trends in tobacco-attributed mortality in China: evidence from successive nationwide prospective cohort studies

BACKGROUND

Chinese men now smoke more than a third of the world's cigarettes, following a large increase in urban then rural usage. Conversely, Chinese women now smoke far less than in previous generations. We assess the oppositely changing effects of tobacco on male and female mortality.

METHODS

Two nationwide prospective studies 15 years apart recruited 220,000 men in about 1991 at ages 40-79 years (first study) and 210,000 men and 300,000 women in about 2006 at ages 35-74 years (second study), with follow-up during 1991-99 (mid-year 1995) and 2006-14 (mid-year 2010), respectively. Cox regression yielded sex-specific adjusted mortality rate ratios (RRs) comparing smokers (including any who had stopped because of illness, but not the other ex-smokers, who are described as having stopped by choice) versus never-smokers.

FINDINGS

Two-thirds of the men smoked; there was little dependence of male smoking prevalence on age, but many smokers had not smoked cigarettes throughout adult life. Comparing men born before and since 1950, in the older generation, the age at which smoking had started was later and, particularly in rural areas, lifelong exclusive cigarette use was less common than in the younger generation. Comparing male mortality RRs in the first study (mid-year 1995) versus those in the second study (mid-year 2010), the proportional excess risk among smokers (RR-1) approximately doubled over this 15-year period (urban: RR 1·32 [95% CI 1·24-1·41] vs 1·65 [1·53-1·79]; rural: RR 1·13 [1·09-1·17] vs 1·22 [1·16-1·29]), as did the smoking-attributed fraction of deaths at ages 40-79 years (urban: 17% vs 26%; rural: 9% vs 14%). In the second study, urban male smokers who had started before age 20 years (which is now typical among both urban and rural young men) had twice the never-smoker mortality rate (RR 1·98, 1·79-2·19, approaching Western RRs), with substantial excess mortality from chronic obstructive pulmonary disease (COPD RR 9·09, 5·11-16·15), lung cancer (RR 3·78, 2·78-5·14), and ischaemic stroke or ischaemic heart disease (combined RR 2·03, 1·66-2·47). Ex-smokers who had stopped by choice (only 3% of ever-smokers in 1991, but 9% in 2006) had little smoking-attributed risk more than 10 years after stopping. Among Chinese women, however, there has been a tenfold intergenerational reduction in smoking uptake rates. In the second study, among women born in the 1930s, 1940s, 1950s, and since 1960 the proportions who had smoked were, respectively, 10%, 5%, 2%, and 1% (3097/30,943, 3265/62,246, 2339/97,344, and 1068/111,933). The smoker versus non-smoker RR of 1·51 (1·40-1·63) for all female mortality at ages 40-79 years accounted for 5%, 3%, 1%, and <1%, respectively, of all the female deaths in these four successive birth cohorts. In 2010, smoking caused about 1 million (840,000 male, 130,000 female) deaths in China.

INTERPRETATION

Smoking will cause about 20% of all adult male deaths in China during the 2010s. The tobacco-attributed proportion is increasing in men, but low, and decreasing, in women. Although overall adult mortality rates are falling, as the adult population of China grows and the proportion of male deaths due to smoking increases, the annual number of deaths in China that are caused by tobacco will rise from about 1 million in 2010 to 2 million in 2030 and 3 million in 2050, unless there is widespread cessation.

FUNDING

Wellcome Trust, MRC, BHF, CR-UK, Kadoorie Charitable Foundation, Chinese MoST and NSFC.

Comparative analysis of pulmonary and extrapulmonary tuberculosis of 411 cases

BACKGROUND

Tuberculosis is a disease that can involve every organ system. While pulmonary tuberculosis is the most common presentation, extrapulmonary tuberculosis (EPT) is also an important clinical problem. The current study aimed to outline and compare the demographic and clinical features of pulmonary and extrapulmonary tuberculosis cases in adults.

METHODS

Medical records of 411 patients (190 women, 221 men) treated between January 2010 and July 2014 in provincial tuberculosis control dispensary was retrospectively reviewed. Demographic and clinical characteristics were compared for pulmonary and extrapulmonary tuberculosis cases.

RESULTS

Of these 411 cases, 208 (50.6%) had pulmonary tuberculosis (PTB) and 203 were diagnosed with extrapulmonary tuberculosis (EPTB) (49.4%). The average ages for PTB and EPTB groups were 33.00-27.00 and 31.00-29.75, respectively (p = 0.513). Men were more frequently affected by PTB (59.6%), while EPTB was more commonly detected in women (52.2%) (p = 0.016). Main diagnostic modalities for PTB were sputum/smear analyses (72.7%), clinical-radiological data (21.7%) and biopsy (6.1%); while biopsy (71.5%), sputum/fluid analysis (18.8%) and clinical-radiological data (4.9%) were used for confirming EPTB (p < 0.0019). The most common sites of EPTB involvement were lymph nodes (39.4%), followed by pleura (23.6%), peritoneum (9.9%) and bone (7.4%).

CONCLUSIONS

Extrapulmonary involvement of tuberculosis is common and females are more likely to be affected. Increased clinical awareness is important since atypical presentations of the disease may constitute diagnostic and therapeutic challenges.

Epidemiologic link between tuberculosis and cigarette/biomass smoke exposure: Limitations despite the vast literature

The geographic overlap between the prevalence of cigarette smoke (CS) exposure and tuberculosis (TB) in the world is striking. In recent years, relatively large number of studies has linked cigarette or biomass fuel smoke exposure and various aspects of TB. Our goals are to summarize the significance of the known published studies, graphically represent reports that quantified the association and discuss their potential limitations. PubMed searches were performed using the key words 'tuberculosis' with 'cigarette', 'tobacco', 'smoke' or 'biomass fuel smoke.' The references of relevant articles were examined for additional pertinent papers. A large number of mostly case-control and cross-sectional studies significantly associate both direct and second-hand smoke exposure with tuberculous infection, active TB, and/or more severe and lethal TB. Fewer link biomass fuel smoke exposure and TB. While a number of studies interpreted the association with multivariate analysis, other confounders are often not accounted for in these analyses. It is also important to emphasize that these retrospective studies can only show an association and not any causal link. We further explored the possibility that even if CS exposure is a risk factor for TB, several mechanisms may be responsible. Numerous studies associate cigarette and biomass smoke exposure with TB but the mechanism(s) remains largely unknown. While the associative link of these two health maladies is well established, more definitive, mechanistic studies are needed to cement the effect of smoke exposure on TB pathogenesis and to utilize this knowledge in empowering public health policies.

Smoking and mortality in a prospective cohort study of elderly Chinese in Hong Kong

BACKGROUND AND AIMS

Large cohort studies on smoking and mortality in elderly people are scarce, and few studies examined smokers aged 85+ years separately. We estimated the risks of all-cause and cause-specific mortality due to smoking in an elderly Chinese cohort in Hong Kong.

DESIGN

A population-based prospective cohort of 65,510 Chinese enrolled from 1998 to 2001 and followed until May 2012.

SETTING

All 18 Elderly Health Service centres in Hong Kong, China.

PARTICIPANTS

Elderly people aged 65+ years.

MEASUREMENTS

Self-reported smoking status was assessed at baseline interview and categorized as never, former and current smokers.

FINDINGS

Compared with never smokers, after adjustment for sex, age, education, social security assistance, housing type, monthly expenditure, alcohol use, depressive symptoms and health status, the hazard ratio (HR) for current smokers was 1.89 [95% confidence interval (CI) = 1.81-1.98] for all participants aged 65+ years at baseline, corresponding to an attributable fraction (AF) of about 50%, which is based on AF = (HR-1)/HR. As the effect of smoking varied with age (P for age interaction <0.001), subgroup analysis by age group showed that the adjusted HR for current smokers aged 65-84 years was 1.93 (95% CI = 1.84-2.03), and for 85+ years was 1.29 (95% CI = 1.05-1.58). All the risk estimates did not vary by sex (P for sex interaction ranged 0.74-0.89).

CONCLUSIONS

In Hong Kong, the risk of death from smoking appears to be the same for Chinese women as it is for men. Half of all deaths in Chinese smokers aged 65 years and older and a quarter of all deaths in Chinese smokers aged 85 years and older are caused by smoking-attributable diseases.

Population attributable risks of cigarette smoking for deaths of all causes, all cancers and other chronic diseases among adults aged 40-74 years in urban Shanghai, China

OBJECTIVE

To evaluate the population attributable risks (PARs) between cigarette smoking and deaths of all causes, all cancers, lung cancer and other chronic diseases in urban Shanghai.

METHODS

In total, 61,480 men aged 40-74 years from 2002 to 2006 and 74,941 women aged 40-70 years from 1997 to 2000 were recruited to undergo baseline surveys in urban Shanghai, with response rates of 74.0% and 92.3%, respectively. A Cox proportional hazards regression model was used to estimate relative risks (RRs) and 95% confidence intervals (95% CIs) of deaths associated with cigarette smoking. PARs and 95% CIs for deaths were estimated from smoking exposure rates and the estimated RRs.

RESULTS

Cigarette smoking was responsible for 23.9% (95% CI: 19.4-28.3%) and 2.4% (95% CI: 1.6-3.2%) of all deaths in men and women, respectively, in our study population. Respiratory disease had the highest PAR in men [37.5% (95% CI: 21.5-51.6%)], followed by cancer [31.3% (95% CI: 24.6-37.7%)] and cardiovascular disease (CVD) [24.1% (95% CI: 16.7-31.2%)]. While the top three PARs were 12.7% (95% CI: 6.1-19.3%), 4.0% (95% CI: 2.4-5.6%), and 1.1% (95% CI: 0.0-2.3%), for respiratory disease, CVD, and cancer, respectively in women. For deaths of lung cancer, the PAR of smoking was 68.4% (95% CI: 58.2-76.5%) in men.

CONCLUSIONS

In urban Shanghai, 23.9% and 2.4% of all deaths in men and women could have been prevented if no people had smoked in the area. Effective control programs against cigarette smoking should be strongly advocated to reduce the increasing smoking-related death burden.

Smoking among Hong Kong Chinese women: behavior, attitudes and experience

BACKGROUND

The numbers of women smoking have risen 72.5% since 1990 with the increasing population - from 56,100 to 96,800 in 2012, reflecting an alarming situation in Hong Kong. The study aimed to describe the smoking behaviour, attitudes and associated factors among women in Hong Kong.

METHODS

A qualitative cross-sectional study involving semi-structured interview was conducted with Chinese women from five community centres in different districts in Hong Kong in 2010. A purposive sample of 73 female participants (24 current smokers, 20 ex-smokers and 29 never-smokers) were recruited. The 73 women were classified by their smoking status and age to form 15 focus groups.

RESULTS

Most informants knew about the general health hazards of smoking, such as cancer and heart or respiratory diseases, but not about the female-specific health consequences of smoking. A few smokers considered smoking to be a weight control strategy, fearing a gain in weight if they gave up. Moreover, a few relied on smoking as a coping strategy to relieve negative emotions and stress. Additionally, a few smokers had misconceptions about giving up: that a loss of concentration would result, that continued smoking would not further affect their health as they had become desensitised to the chemicals in tobacco smoke or that quitting would harm their health.

CONCLUSIONS

This study generates new knowledge about the behavior, attitudes, and experiences related to smoking of current female smokers, ex-smokers and non-smokers in Hong Kong, which is unique as a Chinese but highly westernized community but with a very low female smoking prevalence.

Smoking adversely affects treatment response, outcome and relapse in tuberculosis

The impact of smoking on tuberculosis outcome was evaluated in a territory-wide treatment programme. 16,345 consecutive patients undergoing chemotherapy for active tuberculosis in government chest clinics in Hong Kong from 2001 to 2003 were followed up prospectively for 2 years for treatment outcome and subsequently tracked through the territory-wide tuberculosis notification registry for relapse until the end of 2012. Smoking was associated with more extensive lung disease, lung cavitation and positive sputum smear and culture at the baseline. In both current smokers and ex-smokers, sputum smears and cultures were significantly more likely to remain positive after 2 months of treatment. Both categories of smokers were significantly less likely to achieve cure or treatment completion within 2 years. Overall, 16.7% of unsuccessful treatment outcomes were attributable to smoking, with the key contributor being default in current smokers and death in ex-smokers. Among successful treatment completers, there was a clear gradient (hazard ratios of 1.00, 1.33 and 1.63) of relapse risk from never-smokers to ex-smokers and current smokers, with an overall population attributable risk of 19.4% (current smokers: 12.2%; ex-smokers: 7.2%). Smoking adversely affects baseline disease severity, bacteriological response, treatment outcome and relapse in tuberculosis. Smoking cessation likely reduces relapse and secondary transmission.

The incidence of cancer deaths among hypertensive patients in a large Chinese population: a cohort study

Current evidence is mixed regarding the association between antihypertensive prescriptions and cancer mortality. We evaluated this association in a large Chinese hypertensive population. We followed for five years all patients who were prescribed their first-ever antihypertensive agents between 2001 and 2005 in a public healthcare sector of Hong Kong. The association between antihypertensive drug class and cancer mortality was evaluated by Cox proportional hazard models with propensity score matching. Age, gender, socioeconomic status, service settings, district of residence, proportion of days covered reflecting medication adherence, and the number of comorbidities were adjusted. From 217,910 eligible patients, 9500 (4.4%) died from cancer within five years after their first-ever antihypertensive prescription. Most cancer deaths occurred in the digestive (38.9%) and respiratory system (30.4%); the breast (6.2%); and the lympho-hematopoietic tissues (5.3%). The proportion of patients who died from cancer was the highest in the calcium channel blocker (CCB) group (6.5%), followed by thiazide diuretics (4.4%), angiotensin converting enzyme inhibitors (4.2%) and β-blockers (2.6%). When compared with β-blockers, patients prescribed CCBs (Adjusted Hazard Ratio [AHR]=1.406, 95% C.I. 1.334-1.482, p<0.001) were more likely to die from cancer. Thiazide users were also more likely to suffer from cancer deaths (AHR=1.364, 95% C.I. 1.255-1.483, p<0.001), but became insignificant in stratified analysis. The association between cancer mortality and use of CCB, and perhaps thaizide, may alert physicians to the need for more meticulous and comprehensive care of these patients in clinical practice. We recommend prospective studies to evaluate cause-and-effect relationships of these associations.

Joint effects of smoking and silicosis on diseases to the lungs

Smokers are subject to being more susceptible to the long-term effects of silica dust, whilst it remains unclear whether the joint effect of smoking and silicosis differs amongst diseases to the lungs; this study aims to address this knowledge gap. This was a historical cohort study comprised of 3202 silicotics in Hong Kong during 1981-2005 who were followed up till 31/12/2006. We estimated the standardized mortality ratio (SMR) in the smoking and never smoking silicotics using the mortality rates of male general population indiscriminately by smoking status, but these SMRs were regarded as biased. We adjusted these biased SMRs using "smoking adjustment factors (SAF)". We assessed the multiplicative interaction between smoking and silicosis using 'relative silicosis effect (RSE)' that was the ratio of SAF-corrected SMR of smoking silicotics to the never smokers. A RSE differs significantly from one implies the presence of multiplicative interaction. A significant excess SMR was observed for respiratory diseases (lung cancer, chronic obstructive pulmonary diseases [COPD], silicosis) and other diseases to the lungs (pulmonary heart disease, tuberculosis). All the 'biased-SMRs' in smokers were higher than those in never smokers, but the SAF-corrected SMRs became higher in never smokers. The RSE was 0.95 (95%CI: 0.37-3.55), 0.94 (95%CI: 0.42-2.60), and 0.81 (95%CI: 0.60-1.19) for lung cancer, COPD, and silicosis; whilst it was 1.21 (95%CI: 0.32-10.26) for tuberculosis and 1.02 (95%CI: 0.16-42.90) for pulmonary heart disease. This study firstly demonstrated the joint effect of smoking and silicosis may differ amongst diseases to the lungs, but power is limited.

Mortality attributable to tobacco: review of different methods

BACKGROUND

One of the most important measures for ascertaining the impact of tobacco is the estimation of the mortality attributable to its use. Several indirect methods of quantification are available. The objective of the article is to assess methodologies published and applied in calculating mortality attributable to smoking.

METHODS

A review of the literature was made for the period 1998 to 2005, in the electronic databases MEDLINE. Twelve articles were selected for analysis.

RESULTS

The most widely used methods were the prevalence methods, followed by smoking impact ration method. Ezzati and Lopez showed that the general rate of Smoking attributable mortality (SAM) globally was 12% (18% in men). Across countries, attributable fractions of total adult deaths ranged from 8% in Southern Africa, 13.6% in Brazil (18.1% in men) and 25% in Hong Kong (33% in men).

CONCLUSION

The variations can be attributed to methodological differences and to different estimates of the main tobacco-related illnesses and tobacco prevalence. All methods show limitations of one type or another, yet there is no consensus as to which furnishes the best information.

Changes in smoking behavior and subsequent mortality risk during a 35-year follow-up of a cohort in Xi'an, China

Prospective evidence of the associations of smoking cessation with chronic obstructive pulmonary disease (COPD) and other causes of death in Asia is scarce. Previous studies, which were mostly based on baseline smoking behavior only, were subject to sick-quitter bias and misclassification resulting from changes in smoking behavior during follow-up. We followed up a cohort for 18 years (1976-1994) to assess changes in smoking behavior and then for an additional 17 years (1994-2011) to examine the relationships of continuing to smoke and new quitting with mortality risk in 1,494 Chinese people (961 men, 533 women). Of the baseline current smokers, 38.7% quit between 1976 and 1994. From 1994 to 2011, a total of 488 persons (359 men, 129 women) died. Ever smokers had increased risks of lung cancer, coronary heart disease, thrombotic stroke, and COPD, with dose-response relationships. For all tobacco-related mortality, the relative risk for new quitters compared with continuing smokers was 0.68 (95% confidence interval: 0.46, 0.99) for those who had quit 2-7 years previously and 0.56 (95% confidence interval: 0.37, 0.85) for those who had quit 8 years or more previously. The corresponding relative risks were 0.69 and 0.45 for lung cancer, 0.78 and 0.51 for coronary heart disease, 0.76 and 0.84 for thrombotic stroke, and 0.89 and 0.61 for COPD, respectively. Smoking increased tobacco-related deaths, and particularly deaths from COPD, in China, whereas quitting at middle age (at approximately 50 years of age) substantially reduced the risks of death from these causes. The benefits of smoking cessation were underestimated in previous studies that did not use repeated measures.

Burden of total and cause-specific mortality related to tobacco smoking among adults aged ≥ 45 years in Asia: a pooled analysis of 21 cohorts

BACKGROUND

Tobacco smoking is a major risk factor for many diseases. We sought to quantify the burden of tobacco-smoking-related deaths in Asia, in parts of which men's smoking prevalence is among the world's highest.

METHODS AND FINDINGS

We performed pooled analyses of data from 1,049,929 participants in 21 cohorts in Asia to quantify the risks of total and cause-specific mortality associated with tobacco smoking using adjusted hazard ratios and their 95% confidence intervals. We then estimated smoking-related deaths among adults aged ≥45 y in 2004 in Bangladesh, India, mainland China, Japan, Republic of Korea, Singapore, and Taiwan-accounting for ∼71% of Asia's total population. An approximately 1.44-fold (95% CI = 1.37-1.51) and 1.48-fold (1.38-1.58) elevated risk of death from any cause was found in male and female ever-smokers, respectively. In 2004, active tobacco smoking accounted for approximately 15.8% (95% CI = 14.3%-17.2%) and 3.3% (2.6%-4.0%) of deaths, respectively, in men and women aged ≥45 y in the seven countries/regions combined, with a total number of estimated deaths of ∼1,575,500 (95% CI = 1,398,000-1,744,700). Among men, approximately 11.4%, 30.5%, and 19.8% of deaths due to cardiovascular diseases, cancer, and respiratory diseases, respectively, were attributable to tobacco smoking. Corresponding proportions for East Asian women were 3.7%, 4.6%, and 1.7%, respectively. The strongest association with tobacco smoking was found for lung cancer: a 3- to 4-fold elevated risk, accounting for 60.5% and 16.7% of lung cancer deaths, respectively, in Asian men and East Asian women aged ≥45 y.

CONCLUSIONS

Tobacco smoking is associated with a substantially elevated risk of mortality, accounting for approximately 2 million deaths in adults aged ≥45 y throughout Asia in 2004. It is likely that smoking-related deaths in Asia will continue to rise over the next few decades if no effective smoking control programs are implemented. Please see later in the article for the Editors' Summary.

Adverse lifestyle leads to an annual excess of 2 million deaths in China

Background

Adverse lifestyle factors have been associated with increased mortality, but data are lacking on their combined effect in developing populations, which we address in the present study.

Methods

In a death registry-based, case-control study among Hong Kong Chinese aged 30+y, proxy-reported lifestyle factors 10 y ago were collected for 21,363 cases (81% of all deaths) and 12,048 living controls. Risks associated with poor diet, inactivity, heavy alcohol intake, and smoking for all-cause and cause-specific mortality, adjusting for potential confounders, were determined, and excess deaths for the Chinese population were calculated.

Results

Adjusted odds ratios for all-cause mortality were 1.15 (95% CI 1.09, 1.23), 1.34 (1.27, 1.43), 1.36 (1.21, 1.52), and 1.58 (1.46, 1.70) for poor diet, inactivity, heavy alcohol intake and smoking, respectively. Increasing numbers of adverse lifestyle factors were associated with a dose-dependent increase in adjusted odds ratios of 1.30 (1.20, 1.40), 1.67 (1.54, 1.81), 2.32 (2.08, 2.60), and 3.85 (3.12, 4.75) for 1, 2, 3, and 4 risk factors relative to those with none. The population attributable fraction for all-cause, all-CVD and all-cancer mortality were 26.6%, 15.0%, and 32.1%, resulting in an excess of 2,017,541; 489,884; and 607,517 deaths annually, respectively. Although smoking was associated with the greatest excess loss of life (867,530), heavy drinking (680,466), and physical inactivity (678,317) were similarly important.

Conclusion

Adverse lifestyle factors contribute to one quarter of all deaths in China. Improving lifestyle practices, particularly focussing on moderating alcohol intake and increasing activity, and smoking cessation are critical to reducing the lifestyle-associated health burden.

Are depressive symptoms associated with cardiovascular mortality among older Chinese: a cohort study of 64,000 people in Hong Kong?

BACKGROUND

Depression was positively associated with cardiovascular disease (CVD) or mortality in previous studies. However, whether the observed association can be explained by health status is not clear.

OBJECTIVES

To study the association of depressive symptoms with CVD, stroke, and coronary heart disease (CHD) mortality in older Chinese in Hong Kong, and whether the associations varied by gender or health status.

DESIGN

Prospective population-based study.

SETTING

Elderly Health Centers.

PARTICIPANTS

A total of 62,839 people age 65 or older (21,473 men and 41,366 women) enrolled during July 1998 to December 2001 at all 18 Elderly Health Centers of the Department of Health of Hong Kong.

MEASUREMENTS

Fifteen-item Geriatric Depression Scale (GDS) was used and presence of depressive symptoms was defined by GDS score 8 or more. The cohort was followed up for mortality till March 31, 2009.

RESULTS

Depressive symptoms were only associated with CHD mortality in men (hazard ratio [HR] 1.41, 95% confidence interval [CI]: 1.08-1.84; p for gender interaction = 0.02) adjusted for age, education, monthly expenditure, smoking, alcohol use, physical activity, body mass index, health status, and self-rated health. GDS score was associated with stroke mortality (similarly adjusted HR 1.02 per score, 95% CI: 1.00-1.04) in all subjects (adjusted also for gender), and CHD mortality (1.04 [1.01-1.07]) in men. Health status attenuated but did not modify any associations.

CONCLUSION

Depressive symptoms were independently associated with higher CHD mortality in older Chinese men, and with higher stroke mortality in both genders. However, attenuation by health status, and lack of consistency by gender indicate that these associations could be noncausal and further studies by treatment trials and Mendelian randomization are needed.

Predictors of the incidence of all-cause mortality and deaths due to diabetes and renal diseases among patients newly prescribed antihypertensive agents: a cohort study

BACKGROUND

Randomized trials have shown that the major antihypertensive drug classes are similarly effective to reduce mortality, but whether these drug class difference exists in clinical practice has been scarcely explored. This study evaluated the association between antihypertensive drug class, all-cause mortality and deaths due to diabetes or renal disease in real-life clinical settings.

METHODS

A clinical database in Hong Kong included all patients who were prescribed their first-ever antihypertensive agents between 2001 and 2005 from the public healthcare sector. All patients were followed up for five years, and grouped according to the initial antihypertensive prescription. The associations between antihypertensive drug class, all-cause mortality or combined diabetes and renal mortality, respectively, were evaluated by Cox proportional hazard models.

RESULTS

From 218,047 eligible patients, 33,288 (15.3%) died within five years after their first-ever antihypertensive prescription and among which 1055 patients (0.48%) died of diabetes or renal disease. After adjusted for age, gender, socioeconomic status, service settings, district of residence, medication adherence, and the number of comorbidities, each drug class was similarly likely to be associated with mortality due to diabetes or renal disease [Adjusted Hazard Ratios (AHR) ranged from 0.92 to 1.73, p=0.287-0.939] and all-cause mortality (AHR ranged from 0.83 to 1.02) except for beta-blockers (AHR=0.815, 95% C.I. 0.68-0.87, p=0.024) when ACEI was used as a reference group in propensity score-adjusted analysis.

CONCLUSIONS

These findings provide real-life evidence reinforcing that any major antihypertensive drug class is suitable as a first-line agent for management of hypertension as recommended by international guidelines.

A randomized controlled trial of two different lengths of nicotine replacement therapy for smoking cessation

This study examined if 2-week free nicotine replacement therapy (NRT) would be more effective than 1-week free NRT to help smokers quit smoking at 6 and 12 months. In a single-blinded randomized controlled trial design, 562 Chinese smokers who attended a smoking cessation clinic in Hong Kong, China, were randomly allocated into two groups (A1 and A2): A1 (n = 284) received behavioural counselling with free NRT for 1 week; A2 (n = 278) received similar counselling with free NRT for 2 weeks. All subjects received printed self-help materials to support their quitting efforts. A structured questionnaire was used for data collection, including pattern of NRT use and self-reported 7-day point prevalence quit rate at 6 months and 12 months. Among the participants, the mean number of cigarettes smoked per day was 18.8 (SD = 10.9). By intention-to-treat analysis, 7-day point prevalence quit rates were not significantly different between A1 and A2 groups at 6-month (27.5% versus 27.3%; P = 0.97) and 12-month (21.1% versus 21.2%; P = 0.98) followup. The findings suggest that two-week free NRT was not more effective than 1-week free NRT to increase smoking cessation rate among Chinese smokers.

Alcohol intake and death from cancer in a prospective Chinese elderly cohort study in Hong Kong

BACKGROUND

In observational studies of Western populations, moderate alcohol use is usually associated with lower cancer mortality rates. However, moderate alcohol use (regular drinking of moderate amounts) is socially patterned. Evidence from other contexts can clarify such observations. We examined the association of moderate alcohol use with death from cancer in older Chinese adults from a developed non-Western setting, where occasional alcohol drinking (less than once per week of small amounts) is typical.

METHODS

Multivariable Cox regression analysis was used to assess the adjusted associations of alcohol use with death from cancer using a population-based prospective cohort of 66 820 Chinese aged ≥ 65 years enrolled from July 1998 to December 2001 at all the 18 Elderly Health Centres of the Hong Kong Government Department of Health, and followed till 30 May 2012.

RESULTS

After follow-up for about 10.5 years, 6335 cancer deaths were identified. Most current alcohol users were social drinkers (<1/week). Moderate drinkers had a similar risk of death from non-oesophageal cancer as never drinkers, but a higher risk of oesophageal cancer, adjusted for age, sex, socioeconomic position, lifestyle and health status. Social drinking (<1/week) was associated with a lower risk of death from non-oesophageal cancer, but not from oesophageal cancer.

CONCLUSIONS

In a non-Western setting, no association of moderate alcohol use with death from cancer was found. Occasional social drinking (<1/week) was associated with a lower risk of cancer, suggesting that moderate alcohol use is not protective, but in any setting the attributes of being a typical drinker may be.

Smoking and hemorrhagic stroke mortality in a prospective cohort study of older Chinese

BACKGROUND AND PURPOSE

Hemorrhagic stroke is more common in non-Western settings and does not always share risk factors with other cardiovascular diseases. The association of smoking with hemorrhagic stroke subtypes has not been established. We examined the association of cigarette smoking with hemorrhagic stroke, by subtype (intracerebral hemorrhage and subarachnoid hemorrhage), in a large cohort of older Chinese from Hong Kong.

METHODS

Multivariable Cox regression analysis was used to assess the adjusted associations of smoking at baseline with death from hemorrhagic stroke and its subtypes, using a population-based prospective cohort of 66 820 Chinese aged>65 years enrolled from July 1998 to December 2001 at all the 18 Elderly Health Centers of the Hong Kong Government Department of Health and followed until May 31, 2012.

RESULTS

After follow-up for an average of 10.9 years (SD=3.1), 648 deaths from hemorrhagic stroke had occurred, of which 530 (82%) were intracerebral hemorrhage. Current smoking was associated with a higher risk of hemorrhagic stroke (hazard ratio, 2.19; 95% confidence interval, 1.49-3.22), intracerebral hemorrhage (1.94; 1.25-3.01), and subarachnoid hemorrhage (3.58; 1.62-7.94), adjusted for age, sex, education, public assistance, housing type, monthly expenditure, alcohol use, and exercise. Further adjustment for hypertension and body mass index slightly changed the estimates.

CONCLUSIONS

Smoking is strongly associated with hemorrhagic stroke mortality, particularly for subarachnoid hemorrhage.

Trait mindfulness helps shield decision-making from translating into health-risk behavior

PURPOSE

The cognitive tendency toward mindfulness may influence the enactment of health and risk behaviors by its bringing increased attention to and awareness of decision-making processes underlying behavior. The present study examined the moderating effect of trait mindfulness on associations between intentions to smoke (ITS)/smoking refusal self-efficacy (SRSE) and smoking frequency.

METHODS

Self-reports from Chinese adolescents (N = 5,287; mean age = 16.2 years, standard deviation = .7; 48.8% female) were collected in 24 schools. Smoking frequency was regressed on latent factor interactions Mindful Attention Awareness Scale*ITS and Mindful Attention Awareness Scale*SRSE, adjusting for school clustering effects and covariates.

RESULTS

Both interaction terms were significant in cross-sectional analyses and showed that high ITS predicted higher smoking frequency among those low, relative to high, in trait mindfulness, whereas low SRSE predicted higher smoking frequency among those low, relative to high, in trait mindfulness.

CONCLUSIONS

Findings suggest trait mindfulness possibly shields against decision-making processes that place adolescents at risk for smoking.

Drug adherence and the incidence of coronary heart disease- and stroke-specific mortality among 218,047 patients newly prescribed an antihypertensive medication: a five-year cohort study

Background

Randomized trials have shown that optimal adherence to antihypertensive agents could protect against cardiovascular diseases, but whether adherence reduces cardiovascular deaths in community settings has not been explored so fully. This study evaluates the association between antihypertensive adherence and cardiovascular (coronary heart disease and stroke) mortality in the primary care settings.

Methods

From a territory-wide database in Hong Kong, we included all patients who were prescribed their first-ever antihypertensive agents in the years between 2001 and 2005 from the public healthcare sector. All patients were followed up for five years, and assigned as having poor (Proportion of Days Covered [PDC] < 40%), intermediate (40–79%), and high (≥ 80%) adherence to antihypertensive agents. The association between antihypertensive adherence and cardiovascular mortality was evaluated by using the Cox proportional hazard models.

Results

From a total of 218,047 eligible patients, 3825 patients (1.75%) died of cardiovascular disease within five years after having received their first-ever antihypertensive agents. The proportions of patients having poor, intermediate, and high medication adherence were 32.9%, 12.1%, and 55.0%, respectively. Higher adherence levels at PDC 40%–79% (HR = 0.46, 95% C.I. 0.41–0.52, p < 0.001) and ≥ 80% (HR = 0.91, 95% C.I. 0.85–0.98, p = 0.012) were significantly less likely to be associated with mortality than the poor adherence (PDC0.040) group.

Conclusions

Better antihypertensive adherence was associated with lower cardiovascular mortality. This highlights the need to promote adherence through strategies which have been proved to be effective in clinical settings.

Association between tuberculosis and smoking

Background

The association between smoking and tuberculosis (TB), which has been proven in multiple studies with different study population ethnicity, has not yet received sufficient attention in terms of TB control.

Objectives

The aim of the present study was to determine the association between TB and cigarette smoking in southeastern Iran, an endemic area for tuberculosis.

Patients and Methods

This prospective case-control study conducted at a University-Affiliated Hospital (Boo-Ali Hospital, Zahedan, and Southeastern Iran) from March 2007 to March 2012 enrolled 253 TB patients and 312 healthy controls. Factors including history of cigarette smoking, duration of smoking, number of cigarettes smoked per day, consumption of other drugs (parenteral and non-parenteral), and family history of tuberculosis and smoking, were evaluated in both cases and controls. Univarate and multivariate logistic regressions were performed to compare TB cases and controls. The odds ratio (OR) and 95% confidence intervals (CI) were also estimated.

Results

The results of the study revealed a significant difference between TB and control groups in relation to smoking (P < 0.0001). In multivariate logistic regression, cigarette smokers were 3.1 (95% CI: 1.4-10.3) times more frequent in TB patients compared with controls. Other factors that showed significant differences between TB patients and controls were the use of non-parenteral drugs (OR = 3.6, 95% CI: 2.2-21.4), family history of TB (OR = 6.6, 95% CI: 2.3-18.2), family history of smoking (OR = 2.8, 95% CI: 1.1-8.4), and smoking history of more than 10 years (OR = 1.6, 95% CI: 1.2-9.8).

Conclusions

The present study evidenced the association between TB and smoking. It is therefore recommended to include interventions for smoking cessation in the current TB control practice.

Depressive symptoms and suicide in 56,000 older Chinese: a Hong Kong cohort study

OBJECTIVE

To examine dose-response associations between depressive symptoms and suicide and modification effects of sex, age and health status in older Chinese.

METHODS

We used the Chinese version of the 15-item Geriatric Depression Scale (GDS) to measure depressive symptoms (GDS score ≥ 8) and Cox regression to examine association with suicide mortality in a population-based cohort of 55,946 individuals, aged 65 years or above, enrolled from July 1998 to December 2000 at one of 18 Elderly Health Centres of Hong Kong Department of Health. The cohort was followed up for suicide mortality till 31 March 2009 (mean follow-up 8.7 years).

RESULTS

Depressive symptoms were associated with suicide in men [hazard ratio (HR) 2.03, 95% confidence interval (CI) 0.96-4.29] and women (HR = 2.36, 95% CI 1.31-4.24) after adjusting for age, education, monthly expenditure, smoking, alcohol drinking, physical activity, body mass index, health status, and self-rated health. There was no threshold for GDS score and suicide in either sex. Age, sex and health status did not modify the association.

CONCLUSIONS

Depressive symptoms predict higher suicide risk in older Chinese in a dose-response pattern. These associations were not attenuated by adjustment for health status, suggesting that depressive symptoms in older people are likely to be an independent causal factor for suicide. The GDS score showed no threshold in predicting suicide risk, suggesting that older people with low GDS scores deserve further attention and those with very high scores need urgent intervention.

Smoking and non-communicable disease mortality: prospective study of the population of 40-59-year-old men

Aim.To investigate the prognostic role of cigarette smoking in the end-point development during the 25-year prospective follow-up of 40-59-year-old men.Material and methods. The baseline examination of a representative sample of Tashkent City men took place in 1979-80. During the 25-year follow-up (up to 2005), the death certificate data were collected for the deceased participants of the initial study — men aged 40-59 years at baseline. All-cause mortality, cardiovascular disease (CVD) mortality, cancer mortality, and their association with smoking were analyzed.Results.Out of 862 participants who smoked at baseline, 56,7 % died during 25 years of the prospective follow-up. Among smokers, 25-year all-cause mortality was 34,4 per 1000 person-years, while CVD and cancer mortality was 18,7 and 7,0 per 1000 person-years, respectively. Smoking was a strong predictor of 25-year all-cause mortality: compared to never-smokers, all-cause, CVD, and cancer mortality in smokers was 1,8, 1,6, and 3,5-4,6 times higher.Conclusion.Among all deceased participants, the prevalence of baseline smoking was 61,2 %, while among people who died from CVD or cancer, it was 58,9 % and 71 %, respectively. Among men who were regular smokers at baseline, the levels of all-cause, CVD, and cancer mortality were 1,5, 1,6, and 3,3 times higher than among neversmokers. There was a direct linear association between the contribution of smoking in the end-point development and the follow-up length.

[Effect of lifestyle and health behavior on neutrophil function]

OBJECTIVE

In this study, we investigated the relationships of neutrophil functions with lifestyle factors (namely, subjective stress, exercise habits, smoking habits, alcohol-drinking habits, and self-perceived status health) and health behavior in the Chinese urban elderly.

METHODS

We performed a health survey of the elderly aged 65 years or older living in Tianjin. The subjects were 42 males (69.1 ± 4.1 years old) and 41 females (69.1 ± 4.1 years old). Investigations of subjective stress, exercise habits, smoking habits, alcohol-drinking habits, and self-perceived health status were performed. The phagocytosis and superoxide productivity of neutrophils were measured by the nitroblue tetrazolium (NBT) reduction method. In addition, leukocyte count and serum total protein (TP) level were examined.

RESULTS

The investigations revealed the associations of health behavior (p<0.05) and self-perceived health (p<0.10) with the balance between phagocytosis and subsequent superoxide production.

CONCLUSIONS

The present study revealed that there were correlations of neutrophil functions with lifestyle factors (subjective stress, exercise habits, smoking habits, alcohol-drinking habits, and self-perceived status health) and health behavior in the Chinese urban elderly.

Smoking and the outcome of infection

Smoking has substantial local and systemic adverse effects on the immune system, respiratory tract and skin and soft tissues. Smokers are at increased risk of invasive pneumococcal disease, pneumonia, periodontitis, surgical infections, tuberculosis, influenza and meningococcal disease. The results of several studies indicate that smokers with periodontitis or tuberculosis suffer more severe disease. Data on the impact of smoking on sepsis and pneumonia are controversial and limited, and systematic data regarding the outcome of the majority of infections in smokers are scarce. Abundant data indicate that children exposed to environmental tobacco smoke (ETS) suffer from more severe infections. However, information regarding the effects of ETS on the outcome of infections in adults is limited. Various aspects of the relation between smoking and the outcome of bacterial infection (e.g. potential dose-dependent effects and the interactions between smoking and other environmental factors that may affect the course of infectious diseases) remain to be established.