Association of BMI with risk of CVD mortality and all-cause mortality.

OBJECTIVE: To determine the relationship between BMI and risk of CVD mortality and all-cause mortality among Malaysian adults. DESIGN: Population-based, retrospective cohort study. Participants were followed up for 5 years from 2006 to 2010. Mortality data were obtained via record linkages with the Malaysian National Registration Department. Multiple Cox regression was applied to compare risk of CVD and all-cause mortality between BMI categories adjusting for age, gender and ethnicity. Models were generated for all participants, all participants the first 2 years of follow-up, healthy participants, healthy never smokers, never smokers, current smokers and former smokers. SETTING: All fourteen states in Malaysia. SUBJECTS: Malaysian adults (n 32 839) aged 18 years or above from the third National Health and Morbidity Survey. RESULTS: Total follow-up time was 153 814 person-years with 1035 deaths from all causes and 225 deaths from CVD. Underweight (BMI<18·5 kg/m2) was associated with a significantly increased risk of all-cause mortality, while obesity (BMI ≥30·0 kg/m2) was associated with a heightened risk of CVD mortality. Overweight (BMI=25·0-29·9 kg/m2) was inversely associated with risk of all-cause mortality. Underweight was significantly associated with all-cause mortality in all models except for current smokers. Overweight was inversely associated with all-cause mortality in all participants. Although a positive trend was observed between BMI and CVD mortality in all participants, a significant association was observed only for severe obesity (BMI≥35·0 kg/m2). CONCLUSIONS: Underweight was associated with increased risk of all-cause mortality and obesity with increased risk of CVD mortality. Therefore, maintaining a normal BMI through leading an active lifestyle and healthy dietary habits should continue to be promoted.

Perceived Norms and Smoking Status among Secondary School Students in Kota Tinggi, Johor, Malaysia

Social norms, though an important contributing factor of adolescent smoking in developed countries, has not been extensively studied in Malaysia. The objective of this study was to determine the association between certain perceived norms regarding smoking with smoking status among Malaysian secondary school students in Kota Tinggi, Johor. Data were collected from 2311 respondents consisting of 1379 male and 923 female secondary school students in Kota Tinggi district via a self administered questionnaire. Five perceived norms regarding smoking were assessed, namely: perceived peer smoking prevalence, perceived parental reaction towards adolescent smoking, perceived public perception of adolescent smoking, ever noticed peers smoking inside and outside school and perceived enforcement of anti-smoking policy in school and their association with smoking status. Multiple logistic regressions controlling for gender, peer smoking and family smoking was performed. Of the five perceived norms, four were associated with smoking status, (perceived peer smoking prevalence (p<0.001value), ever seen friends smoking inside or outside school (p <0.001), perceived parental reaction towards adolescent smoking (p<0.001 value) and perceived public disapproval (p <0.001)). Higher odds for smoking was observed for adolescents who: perceived a few (aOR 3.22), many (aOR 3.01) or a lot (aOR 3.52) of their peers smoke; had ever observed friends smoking in or outside of school (aOR 1.79); perceived their parents will react badly to smoking (aOR 0.84) or perceived the public disapprove of smoking (aOR 0.93). These results suggest that perception of social norms influence adolescents’ decision to smoke, thus measures to curb smoking incidence amongst adolescents should address these perceptions of social norms.