title: Relationship between increase of serum homocysteine caused by smoking and oxidative damage in elderly patients with cardiovascular disease.
abstract: BACKGROUND
  To investigate the mechanism of smoking on cardiovascular diseases.
  
  
  METHODS
  576 elderly patients with cardiovascular diseases in stable condition were consecutive recruited, asked about the living habits and smoking history in a way of face to face.
  
  
  RESULTS
  Of all the enrolled patients, current smoking rate was 34.8% for males and 3.4% for females. Average smoking quantity was 17 cigarettes per day and incidence of hyperhomocysteinemia was 38.0%. The homocysteine level in current smokers was significantly higher than that in never smokers (P = 0.004); while the serum folic acid and serum superoxide dismutase (SOD) level were significantly lower those in never smokers (P = 0.012; P = 0.004). The daily smoking consumption and the pack-years of smoking were significantly positively correlated with total homocysteine (tHcy) level (P = 0.020; P = 0.003). The reduced serum SOD level might be associated with increased risk of hypertension (P = 0.023), coronary heart disease (P = 0.018), and stroke (P = 0.035). However, the elevated serum tHcy level was not correlated with increased risk of hypertension and coronary heart disease, while may increase the risk of ischemic stroke (P = 0.075).
  
  
  CONCLUSIONS
  Smoking status is still prevalent among Chinese elderly patients with cardiovascular diseases, which causes the increase of serum tHcy and the decrease of serum folate as well as SOD; smoking consumption per day and pack-years of smoking have indirect effects on tHcy. And decrease of serum SOD is a risk factor for cardiovascular diseases, increase of serum tHcy may be associated with changes of metabolism caused by oxidative damage.
authors.affiliation: Department of Clinical Nutrition, Tongji Hospital of Tongji University Shanghai 200065, China.
authors.forename: Shengfang
authors.initials: S
authors.lastname: Chen
authors.affiliation: Department of Clinical Nutrition, Tongji Hospital of Tongji University Shanghai 200065, China.
authors.forename: Ping
authors.initials: P
authors.lastname: Wu
authors.affiliation: Department of Cardiology, Tongji Hospital of Tongji University Shanghai 200065, China.
authors.forename: Lin
authors.initials: L
authors.lastname: Zhou
authors.affiliation: Department of Cardiology, Tongji Hospital of Tongji University Shanghai 200065, China.
authors.forename: Yuqin
authors.initials: Y
authors.lastname: Shen
authors.affiliation: Department of Clinical Nutrition, Tongji Hospital of Tongji University Shanghai 200065, China.
authors.forename: Yunjie
authors.initials: Y
authors.lastname: Li
authors.affiliation: Department of Cardiology, Tongji Hospital of Tongji University Shanghai 200065, China.
authors.forename: Haoming
authors.initials: H
authors.lastname: Song
keywords: Cardiovascular disease; cigarette smoking; homocysteine; superoxide dismutase