Background: Elevated serum phosphorus has been linked to mortality among patients with renal failure and in one study in the general population. The aim of our study was to examine the association of serum phosphorus level with carotid atherosclerosis in the general population.
Methods: We determined the association of serum phosphorus levels with carotid intima-media thickness (cIMT) in 13,340 subjects 45-64 years old without known coronary heart disease, stroke, or renal disease from the Atherosclerosis Risk in Communities (ARIC) study.
Results: Phosphorus levels were significantly associated with age, female gender, diabetes mellitus, hypertension, hypercholesterolemia and fibrinogen levels (p < 0.0001 for each), but not with estimated glomerular filtration rate (eGFR). Age- and sex-adjusted mean cIMT ranged from 0.718 to 0.736 mm for the lowest to the highest quintile of serum phosphorus (p-value for trend < 0.0001). This relationship was attenuated but remained statistically significant after adjustment for atherosclerotic risk factors and eGFR (trend p < 0.0001) in men but not in women. In a multivariable model, a one standard deviation increase in baseline serum phosphorus (0.48 mg/dL) was associated with a 0.012 mm increase in mean cIMT (p < 0.007) in men.
Conclusion: In a population-based cohort of subjects free of overt cardiovascular and renal disease serum phosphorus was positively associated with cIMT independent of traditional risk factors for atherosclerosis and eGFR in men but not in women.