Socioeconomic inequality in cigarette smoking: Trends by gender, age, and socioeconomic position in South Korea, 1989–2003

Abstract

Objective.

The aim of this study was to examine trends of socioeconomic differentials in smoking rates by gender, age, and socioeconomic position in South Korea.

Methods.

We used data from five Social Statistical Surveys of Korea National Statistical Office from 1989 to 2003. This study included 344,969 men and women aged 20 or over. Socioeconomic position indicators were education and occupation.

Results.

Age-standardized smoking rates decreased in all age groups of men and women aged 45+ between 1989 and 2003, while smoking rates among women aged 20–44 did not decrease. Education was inversely associated with smoking in both genders. Those with manual occupations had greater smoking rates than those who performed non-manual labor. Based on the relative index of inequality, unfavorable inequality trends toward low education were detected in both genders aged 20–44. However, these trends were not found at ages 45–64. For occupational class, the relative inequality in smoking measured by odds ratios remained stable among men and women between 1995 and 2003.

Conclusions.

Continuous and progressive anti-smoking policy measures should be directed toward South Korean men whose smoking rates are still high. Policy efforts to reduce socioeconomic inequality in smoking, especially among young adult men and women, should be exercised. In addition, additional anti-smoking policy measures toward young women's smoking habits need to be developed in South Korea.

Introduction

It is well known that cigarette smoking causes short- and long-term morbidity and mortality (US Department of Health and Human Services, 1989, International Agency for Research on Cancer, 2004, Doll et al., 2004). Its inverse relation with socioeconomic position (SEP) is also known to be a factor in widening socioeconomic health inequalities (Jarvis and Wardle, 1999). Trends in smoking rates by SEP have been documented in Great Britain (Jarvis and Wardle, 1999, Bartley et al., 2000), northern and southern European countries (Lahelma et al., 1997, Peltonen et al., 1998, Osler et al., 2000, Borrell et al., 2000, Marques-Vidal et al., 2001, Federico et al., 2004), the United States (Pierce et al., 1989) and Australia (Bennett, 1995). In addition, some studies have examined smoking trends in several countries simultaneously (Graham, 1996, Giskes et al., 2005). However, with the exception of one recent report (Cho et al., 2004), studies on smoking trends by SEP in Asian countries, including South Korea, have generally been scarce. This is significant given the fact that many Asian countries not only lead the world in smoking rates by men but have recently experienced enormous economic and social changes that might affect smoking rates.

Generally, trends in socioeconomic differentials in smoking have been documented according to either education (Pierce et al., 1989, Lahelma et al., 1997, Peltonen et al., 1998, Osler et al., 2000, Marques-Vidal et al., 2001) or occupation (Bennett, 1995, Bartley et al., 2000, Borrell et al., 2000). However, prior studies have rarely employed both factors simultaneously as SEP indicators. Because SEP indicators have distinct influences in promoting or damaging an individual's health (Lynch and Kaplan, 2000), it is worth investigating trends in smoking by multiple SEP measures. Furthermore, gender- and age-specific analyses may help prioritize the population groups in which policy efforts to reduce smoking inequalities should be further exercised. In this study, we examined trends of socioeconomic differentials in smoking by gender, age, and SEP indicators (education and occupational class) between 1989 and 2003, using nationally representative samples of South Korea.