Prevalence and Characteristics of Smoking Among School-Going Adolescents in Kuala Lumpur, Malaysia

Abstract

Background: According to the World Health Organization (WHO) (2014), noncommunicable diseases (NCDs) such as cancer, cardiovascular disease and respiratory disease account for a majority of premature deaths in the Malaysian population. Tobacco smoking remains a leading risk factor for these diseases. Although there have been previous population-level studies which have highlighted adolescent smokers in Malaysia, little has been done to specifically ascertain smoking prevalence within a school-going population using objective measurement tools. Aim: This study aimed to identify the prevalence of school-going adolescent smokers in Kuala Lumpur via an objective measurement - expired carbon monoxide (CO) in parts per million (ppm). Methods: This study was a cross-sectional study that involved 2,679 high school-going adolescents aged between 13 to 18 years old in Kuala Lumpur, Malaysia. The level of exhaled CO (Smokerlyzer test) of all the participants was measured. Participants were also administered with a survey conducted right after the Smokerlyzer test to determine i) whether they smoked or not; ii) type of tobacco products used if smoked; iii) vaping or shisha usage; and iv) exposure to secondhand smoke. The categorization of smoking status was based on CO-ppm reading: ≤ 3 ppm (nonsmoker); 3 < ppm ≤ 6 (light smoker or nonsmoker breathing in poor air quality or passive smoke inhalation); ≥ 7 ppm (regular smoker with higher levels of CO in blood). Descriptive analysis was conducted to determine the demographics of the study population. Inferential analysis was carried out utilizing χ2 tests or Student t-tests to test associations between smoking status and other independent variables. One-way ANOVA test was conducted to compare the differences in CO-ppm readings. Results: The mean age of the adolescents (n=2,679) was 14.5 ± 1.2 years old (median: 14) and 55.1% were male. Interestingly, vaping was the most commonly used method of tobacco use among the studied adolescents, regardless of gender, followed by cigarettes and shisha. The mean CO-ppm reading for male adolescents was significantly higher than female adolescents. Passive smoke inhalation (exposure to secondhand smoke) was significantly associated with higher readings of CO-ppm. A significant association was determined between status of exposure to secondhand smoke and a history of usage of any form of tobacco products. Conclusion: The prevalence of smoking adolescents, regardless of gender, in Kuala Lumpur remains at a worrying state. Objective measurements such as Smokerlyzer test can be coupled with self-reported questionnaire in targeting adolescent smokers within a structured setting such as a school and can help form part of an effective school-based smoking cessation intervention program targeting adolescents in Malaysia. This is in line with efforts to make Malaysia a smoke-free nation by 2045.