Reference range of serum homocysteine level for the northern Persian Gulf

Homocysteine (Hcy), an intermediate form generated during the metabolism of methionine, is associated with cardiovascular diseases. There is little information available about serum concentration of Hcy in healthy Iranian population. In the present study, we assessed the reference range of serum Hcy level among inhabitants of the northern Persian Gulf. In the Persian Gulf Healthy Heart Study (PGHHS) which used a multistage, stratified, clustered sampling, we measured fasting serum Hcy level using enzyme immunoassay method with an accuracy limit of 1 µmol/ L. Confounding factors such as smoking, alcohol consumption, drugs and chronic diseases were eliminated. Reference range for homocysteine level was considered between 5 and 95 percentiles. A total of 886 participants (39.3% female, 60.7% male) were evaluated. Mean plasma Hcy level was 14.58 ± 7.29 µmol/ L and was higher in men than women. Reference range for Hcy level was 8.35-31.1 µmol/ L in males and 2.39-24.31 µmol/ L in females. There was no difference among age groups for serum Hcy level. The Hcy level in the northern Persian Gulf general population is high. Since high Hcy level has been shown as a risk factor of cardiovascular diseases in various studies, it is essential to study the reasons of this high level of Hcy in this region.