OBJECTIVES: The purpose of this study was to identify any influence of socioeconomic status on smoking and smoking cessation in a situation where genetic factors are controlled. METHODS: The sample for this study was 2502 members of the twins and families cohort who participated in the Korean Healthy Twins Study from 2005 to 2009. Groups of brothers or sisters, including twins and fraternal twins, were compared in terms of smoking and smoking cessation behaviors according to differences in socioeconomic status and gender. RESULTS: In a situation with complete control of genetic factors, results showed that the daily smoking amount, cumulative smoking amount, and dependence on nicotine decreased with higher-status occupations, and the rate of smoking and amount of cumulative smoking decreased with higher levels of education. Regarding smoking cessation behavior, a higher level of education was associated with a lower smoking cessation rate, and no significant gender differences were found. CONCLUSIONS: Environmental factors had a stronger influence on smoking behavior than did genetic factors. Genetic factors had greater influence on smoking cessation than did environmental factors; however, this requires verification in further studies.
Adult ; Female ; Genetic Predisposition to Disease ; Health Behavior ; Humans ; Korea ; Male ; Sex Factors ; Smoking/*epidemiology/genetics ; *Smoking Cessation ; *Social Class ; *Social Environment ; Socioeconomic Factors

OBJECTIVES: We examined health care disparities in Korean urban homeless people and individual characteristics associated with the utilization of health care. METHODS: We selected a sample of 203 homeless individuals at streets, shelters, and drop-in centers in Seoul and Daejeon by a quota sampling method. We surveyed demographic information, information related to using health care, and health status with a questionnaire. Logistic regression analysis was adopted to identify factors associated with using health care and to reveal health care disparities within the Korean urban homeless population. RESULTS: Among 203 respondents, 89 reported that they had visited health care providers at least once in the past 6 months. Twenty persons (22.5%) in the group that used health care (n = 89) reported feeling discriminated against. After adjustment for age, sex, marital status, educational level, monthly income, perceived health status, Beck Depression Inventory score, homeless period, and other covariates, three factors were significantly associated with medical utilization: female sex (adjusted odds ratio [aOR, 15.95; 95% CI, 3.97 to 64.04], having three or more diseases (aOR, 24.58; 95% CI, 4.23 to 142.78), and non-street residency (aOR, 11.39; 95% CI, 3.58 to 36.24). CONCLUSIONS: Health care disparities in Seoul and Daejeon homeless exist in terms of the main place to stay, physical illnesses, and gender. Under the current homeless support system in South Korea, street homeless have poorer accessibility to health care versus non-street homeless. To provide equitable medical aid for homeless people, strategies to overcome barriers against health care for the street homeless are needed.
Adult ; Aged ; Confidence Intervals ; Cross-Sectional Studies ; Female ; Health Services/statistics & numerical data/*utilization ; *Health Status Disparities ; Homeless Persons/*statistics & numerical data ; Humans ; Logistic Models ; Male ; Middle Aged ; Odds Ratio ; Psychometrics ; Questionnaires ; Republic of Korea/epidemiology ; Urban Population/*statistics & numerical data ; Young Adult