Related Experiment Videos
Serum total homocysteine and coronary heart disease
Insights
Elevated serum homocysteine is an independent risk factor for coronary heart disease (CHD) in the general population. This study found no evidence of a threshold level, indicating that higher homocysteine is consistently linked to increased CHD risk.
Area of Science:
- Cardiovascular Epidemiology
- Clinical Biochemistry
Background:
- Previous research suggests a link between high homocysteine levels and coronary heart disease (CHD).
- A prior US physician study indicated homocysteine is associated with myocardial infarction (MI), but only above a specific threshold.
Purpose of the Study:
- To investigate the association between serum total homocysteine levels and the risk of developing CHD in a general Norwegian population.
- To determine if a threshold level of homocysteine exists for CHD risk.
Main Methods:
- A nested case-control study was conducted using data from 21,826 individuals in Tromsø, Norway.
- 123 participants who developed CHD post-screening were compared with four controls each, selected from those initially free of MI.
Main Results:
- Cases with CHD had significantly higher mean homocysteine levels than controls (12.7 vs. 11.3 mumol/l, P = 0.002).
- A 4 mumol/l increase in serum homocysteine was associated with a 41% increased relative risk of CHD (RR 1.41), which persisted after adjusting for confounders (RR 1.32).
- No threshold level for homocysteine was identified; the association with CHD risk was present across all measured levels.
Conclusions:
- Serum total homocysteine is an independent risk factor for CHD in the general population.
- The association between homocysteine and CHD risk does not appear to have a threshold level.
Background:
Several studies have observed high plasma levels of homocysteine among patients with coronary heart disease (CHD). The only prospective study was based on US physicians, and concluded that homocysteine was associated with subsequent myocardial infarction (MI). However, the association was limited to those above a threshold level of homocysteine.
Methods:
We conducted a nested case-control study among the 21,826 subjects, aged 12-61 years, who were surveyed in the municipality of Tromsø, Norway. Among those free from MI at the screening, 123 later developed CHD. Four controls were selected for each case.
Results:
Level of homocysteine was higher in cases than in controls (12.7 +/- 4.7 versus 11.3 +/- 3.7 mumol/l (mean +/- SD); P = 0.002). The relative risk for a 4 mumol/l increase in serum homocysteine was 1.41 (95% confidence interval (CI): 1.16-1.71). Adjusting for possible confounders reduced the relative risk to 1.32 (95% CI: 1.05-1.65). There was no threshold level above which serum homocysteine is associated with CHD events.
Conclusions:
In the general population serum total homocysteine is an independent risk factor for CHD with no threshold level.