Levels of Serum Phosphorus and Cardiovascular Surrogate Markers

AIM: This study aimed to evaluate the cross-sectional association between serum phosphorus and arterial stiffness among a health checkup population. METHODS: The study population included 26791 individuals without impaired kidney function. Arterial stiffness was measured by brachial-ankle pulse wave velocity (baPWV), ankle brachial index (ABI), and augmentation index (AI) by the radial artery waveform analysis. Linear or logistic regression model was used to appropriately evaluate the association between phosphorus levels and arterial stiffness markers. RESULTS: The mean age of the population was 49 years and 67% were male. The phosphorus level was divided into quintiles. After multivariate adjustments, participants in the fourth (3.90-4.17 mg/dL) and fifth quintile (≥ 4.18 mg/dL) of serum phosphorus had increased the level of baPWV with linear regression coefficients of 11.9 [95% confidence interval (CI): 5.6-18.2] and 17.2 (95% CI: 10.9-23.5), respectively, compared with those in the first quintile (＜3.34 mg/dL). No significant associations were found between each quintile of phosphorus and ABI ＜0.9. However, participants in the fifth quintile of phosphorus had an increased risk of ABI ≥ 1.3 with an odds ratio (OR) of 1.2 (95% CI: 1.0-1.5) compared with the reference quintile. Furthermore, the increased risks could be observed for AI ＞97% throughout the second to fifth quintile of phosphorus and the ORs were 1.1 (95% CI: 1.0-1.3), 1.2 (95% CI: 1.0-1.4), 1.3 (95% CI: 1.1-1.5), and 1.5 (95% CI: 1.3-1.7), respectively. CONCLUSIONS: Higher serum phosphorus levels, even within the normal range, are associated with markers of arterial stiffness among general population with normal kidney function.