Trajectory of Smoking and Incidence of Atherosclerotic Cardiovascular Disease among Korean Young Adult Men

Physical activity, sedentary behavior, and cardiovascular disease risk in Korea: a trajectory analysis

OBJECTIVES

To identify the distinct trajectories of sedentary behavior (SB) and explore whether reduced cardiovascular disease (CVD) risk was associated with a distinct trajectory of physical activity (PA).

METHODS

We analyzed data from 6,425 people who participated in the Korean Health Panel Survey over a period of 10 years. The participants' self-reported SB and PA were assessed annually, and trajectory groups were identified using a group-based trajectory model for longitudinal data analysis. Logistic regression analysis was performed to assess the association between CVD risk (10-year cumulative incidence) and the trajectories of SB and PA. The adjusted variables included socio-demographic factors, the predisposing diseases of CVD, and baseline health behaviors.

RESULTS

Trajectory analysis identified 4 SB trajectory groups: SB group 1 (low and slightly increasing trend, 53.1%), SB group 2 (high and rapidly decreasing trend, 14.7%), SB group 3 (high and slightly decreasing trend, 9.9%), and SB group 4 (low and rapidly increasing trend, 22.2%). The 3 PA trajectory groups were PA group 1 (moderate and slightly decreasing trend, 32.1%), PA group 2 (low and slightly decreasing trend, 57.3%), and PA group 3 (maintained inactivity, 10.7%). By the 10-year follow-up, 577 cases of incident CVD had occurred. We also noted a 50% reduction in the risk of CVD when SB group 4 was accompanied by PA group 1 (odds ratio, 0.50; 95% confidence interval, 0.28 to 0.90).

CONCLUSIONS

Despite increased time spent in SB, maintaining PA about 2 days to 3 days per week reduced the occurrence of CVD.

Smoking trajectory and cancer risk: A population-based cohort study

INTRODUCTION

Smoking behavior can change with time and lead to different health outcomes. This study explored the trajectory of smoking and its relationship with cancer incidence and mortality among Korean male adults.

METHODS

We used 2002–2018 data from the National Health Insurance Service (NHIS). Smoking status was repeatedly measured in four waves of general health examinations provided by the NHIS between 2002 and 2009. Cancer incidence and mortality were tracked from 2010 to 2018. Trajectory analysis was used to identify the patterns of smoking. The hazard ratio was calculated using Cox proportional regression models.

RESULTS

For the 2448548 men (≥20 years), 137788 cases of cancers and 41146 cancer deaths were found. We identified six trajectory groups: never smokers, former smokers, new current smokers, decreasing light smokers, steady moderate smokers, and steady heavy smokers. All smoking groups had an increased risk of cancer. The steady heavy smokers showed higher cancer incidence and mortality rate than the steady non-smokers (hazard ratio, HR=1.53; 95% CI: 1.49–1.58 and HR=2.64; 95% CI: 2.50–2.79, respectively). The cancer-specific analysis showed that the larynx and lung cancer incidence and mortality rate of the smoking group were higher than in never smokers.

CONCLUSIONS

Smoking, even at low doses, increases the risk of most cancers in men. Quitting or reducing smoking, especially at a young age, can lower cancer incidence and mortality. This study may provide more objective results on the relationship between smoking and cancer, because smoking behavior was examined at multiple time points.

Association of shift work with cardiovascular disease risk among Chinese workers

To evaluate the association of shift work with 10-year cardiovascular disease (CVD) risk among Chinese workers. We included 23,064 workers in the first follow-up of the Dongfeng-Tongji cohort study. Questionnaires and physical examinations were conducted to collect data for all participants. Framingham Risk Score was calculated according to the multivariable risk algorithms, and used to evaluate 10-year CVD risk. Logistic regression models were used to assess the relationship between shift work and 10-year CVD risk. Among 23,064 individuals, 51.92% of workers suffered shift work, and the proportions of shift work duration of 1-<10, 10-<20, and ≥20 years were 17.29%, 17.35% and 17.30%, respectively. Compared with individuals without a shift work history, the odds ratios (ORs) and 95% confidence intervals (CIs) of 10-year CVD were 1.027 (0.900-1.173), 1.058 (0.927-1.206) and 1.191 (1.036-1.368) for individuals with shift work duration of 1-<10 years, 10-<20 years, and ≥20 years, respectively, after adjusting for potential confounders. And the association was more obvious in males. When shift work and obesity were combined, the OR (95%CI) of high 10-year CVD risk (3.373, 2.390-4.761) was significantly increased for obese individuals with shift work of ≥20 years. Besides, the OR (95%CI) for higher 10-year CVD risk associated with shift work decreased as the leaving shift work duration prolonged. Shift work is associated with a higher 10-year CVD risk, especially among males. Obesity has a synergistic effect on such association while leaving shift work reduces such association.

Trajectory of smoking and early bladder cancer risk among Korean young adult men

Objectives

The aim of this study was to examine the risk of bladder cancer according to the trajectory pattern of amount of smoking among Korean young adult men.

Methods

Smoking status was assessed with a standardized questionnaire in the Korean Life Course Health Study (KLCHS). Trajectory analyses were performed among young adult men using seven repeated surveys of cigarette per day (CPD) every two years from 1992 to 2005. The occurrence of bladder cancer was tracked from 2006 to 2016. The Cox proportional models were used to calculate the hazard ratio (HR) (95% confidence interval) of smoking patterns on bladder cancer.

Results

The mean (standard deviation) age of the 161,069 participants was 34.0 (3.9) years, and 2,280,143 person-years (PY) were examined during the follow-up period of 14.2 (median 14.3) years. During this period, 263 new cases of bladder cancer occurred (11.5/100,000 PY). Among the six trajectory groups (low steady, lowering, rise and fall, high steady, rise and sharp fall, and very high steady), there was a higher risk of developing bladder cancer in the all the other groups compared to the low steady group. The highest risk group was the very high steady group, with HR 2.83 (95% CI 1.79–4.49). In addition, the risk of bladder cancer was 2.61 (95% CI 1.50–4.54) in the rise and sharp fall group.

Conclusion

The risk of bladder cancer did not show much difference according to trajectories, except for low steady group. Thus quitting smoking should be the priority to lower the risk of bladder cancer in smokers.

Electronic supplementary material

The online version of this article (10.1007/s10552-020-01335-8) contains supplementary material, which is available to authorized users.

Substance Abuse and Public Health: A Multilevel Perspective and Multiple Responses

Substance abuse has been a thorny public health concern throughout human history. Manifestly, prevention and treatment are the two main strategies commonly adopted to tackle the problem of substance abuse. They are in fact cross-disciplinary, and they relate to the various domains of heredity, biology, psychology, cognitive science, family, social development and cultural structures. This special issue, "Substance Abuse, Environment and Public Health," has published empirical studies from different regions and countries globally to enhance the international exchange of latest views and findings on the etiology, processes and influences of substance abuse across different domains, through which a multilevel perspective is considered more helpful for analyzing its complex nature, courses and consequences. This in turn suggests the possible need to employ multiple responses dynamically and integratively in the prevention and treatment of substance abuse.