Abstract
Purpose. Cigarette smoking is considered to increase morbidity and the mortality risk of cardiovascular diseases. B vitamins regulate the metabolism of homocysteine via remethylation and trans‐sulfuration pathways. The purpose of this study was to investigate homocysteine concentrations, vitamin status, anthropometric and haematological measurements of healthy smokers compared with healthy non‐smoking subjects.
Design. This cross‐sectional study was carried out among smokers and non‐smokers from suburban and urban residential areas in Bangkok, Thailand.
Materials and methods. 174 smokers and 97 non‐smokers (aged 19–62), who participated voluntarily in the study, were investigated. Total homocysteine, folate, vitamin B2, B6, B12, and C concentrations were measured.
Results. Total homocysteine concentrations in plasma were significantly higher in smokers than non‐smokers. Vitamin B2, folate, B12 and C concentrations were significantly lower among smokers than non‐smokers but vitamin B6 was not significantly different between these groups. Total homocysteine concentration had a significantly positive correlation with waist/hip ratio and smoking characteristics such as the number of cigarettes per day and pack‐years but a significantly negative association with folate and vitamin B12. There were significant positive associations among the number of cigarettes smoked per day, white blood cell (WBC) count and waist/hip ratio. Furthermore, the prevalence of hyperhomocysteinemia in smokers (62%) was more common than in non‐smokers (33%).
Conclusion. These findings suggest that increased plasma total homocysteine concentrations in healthy Thai smokers may be explained by a low status of the B vitamins that are involved in homocysteine metabolism such as vitamin B2, folate, and B12. The elevation of the number of cigarettes smoked per day and pack‐years, WBC count, and high percentage of hyperhomocysteinemia among smokers may contribute to increased risk of atherosclerosis or the development of cardiovascular disease.