Association between serum phosphorus and subclinical coronary atherosclerosis in asymptomatic Korean individuals without kidney dysfunction

Serum phosphorus concentration and its association with the degree and pattern of intracranial arterial calcification

BACKGROUND AND AIM

The aim of this study was to determine whether the serum phosphorus concentrations (SPC) are associated with the degree and pattern of intracranial arterial calcification (IAC) in patients with normal renal function or mild-moderate renal impairment.

METHODS AND RESULTS

A total of 513 patients were enrolled in this study. The degree of IAC measured by IAC scores was evaluated on non-contrast head computed tomography (CT) images and IAC was classified as intimal or medial calcification. Study participants were classified according to IAC degrees (mild, moderate and severe) and patterns (intimal and medial calcification). A multivariate regression model was used to assess the independent relationship of SPC with IAC scores and patterns. Of 513 study participants (mean [SD] age, 68.3 [10.3] years; 246 females [48%]), the mean SPC was 1.07 ± 0.17 mmol/L and IAC scores was 4.0 (3.0-5.0). Multivariate analysis showed that higher serum phosphorus was a significant risk factor for moderate/severe IAC in both patients with eGFR ≥60 ml/min/1.73 m2 (odds ratio [OR], 1.27; 95% confidence interval [CI], 1.01-1.59; P < 0.05) and eGFR <60 ml/min/1.73 m2 (OR, 1.92; 95% CI, 1.04-3.57; P < 0.05), when those with mild IAC were considered as the reference group. However, higher SPC was associated with an increased odds of medial calcification only in patients with eGFR <60 ml/min/1.73 m2 (OR, 1.67; 95% CI, 1.08 to 2.61).

CONCLUSIONS

High levels of serum phosphorus were positively correlated with the degree of IAC, and this significant effect on medial IAC was only present in patients with impaired renal function (eGFR <60 ml/min/1.73 m2).

High Serum Phosphate Is Associated with Cardiovascular Mortality and Subclinical Coronary Atherosclerosis: Systematic Review and Meta-Analysis

(1) Background: Cardiovascular diseases (CVDs) are the leading cause of mortality worldwide. The aim of the study was to examine the existing published results of the association between elevated serum phosphate concentrations and cardiovascular mortality, along with the CVD incidence and subclinical coronary atherosclerosis, in primary prevention among non-selected samples of the general population. (2) Methods: A systematic review and meta-analysis were carried out using literature obtained from PubMed, SCOPUS, and the Web Of Science until March 2024 and following the PRISMA guidelines. Relevant information was extracted and presented. Random and fixed effects models were used to estimate the pooled odds ratio (OR) and hazard ratio (HR) with their 95% coefficient interval (CI), and I2 was used to assess heterogeneity. (3) Results: Twenty-five studies met our inclusion criteria and were included in the meta-analysis (11 cross-sectional and 14 cohort studies). For cardiovascular mortality, which included 7 cohort studies and 41,764 adults, the pooled HR was 1.44 (95% CIs 1.28, 1.61; I2 0%) when the highest versus the reference level of serum phosphate concentrations were compared. For CVDs, which included 8 cohort studies and 61,723 adults, the pooled HR was 1.12 (95% CIs 0.99, 1.27; I2 51%). For subclinical coronary atherosclerosis, which included 11 cross-sectional studies and 24,820 adults, the pooled OR was 1.44 (95% CIs 1.15, 1.79; I2 88%). (4) Conclusions: The highest serum phosphate concentrations were positively associated with a 44% increased risk of cardiovascular mortality and subclinical coronary atherosclerosis.

The association of renal impairment with different patterns of intracranial arterial calcification: Intimal and medial calcification

BACKGROUND AND AIMS

Increasing knowledge about calcification together with improved imaging techniques provided evidence that intracranial arterial calcification (IAC) can be divided into two distinct entities: intimal and medial calcification. The purpose of this study was to investigate the association between kidney function and the two patterns of IAC, which could clarify the underlying mechanisms of intimal or medial calcification and its clinical consequence.

METHODS

A total of 516 participants were enrolled in this study. Kidney function was assessed using the estimated glomerular filtration rate (eGFR) based on modified glomerular filtration rate estimating equation. The degree of IAC measured by IAC scores was evaluated on non-contrast head computed tomography (CT) images and IAC was classified as intimal or medial calcification. Associations of kidney function with IAC scores and patterns were assessed sing multivariate logistic regression analysis.

RESULTS

In 440 patients (85.27%) with IAC, 189 (42.95%) had predominant intimal calcifications and 251 (57.05%) had predominant medial calcifications. Multivariate analysis revealed that lower eGFR level (eGFR <60 ml/min/1.73 m²) was associated with higher IAC scores (odds ratio [OR] 2.01; 95% confidence interval [CI], 1.50-2.71; p < 0.001). Medial calcification was more frequent in the lower eGFR group (eGFR <60 ml/min/1.73 m²) compared to the other two groups with eGFR 60 to 89 and eGFR >90 ml/min/1.73 m² (78.72% vs. 53.65%, p < 0.001; 78.72% vs. 47.78%, p < 0.001). In multivariable analysis, impaired kidney function was associated with an increased odds of medial calcification presence in patients with eGFR <60 ml/min/1.73 m² (OR, 1.47; 95% CI, 1.05 to 2.06).

CONCLUSIONS

Our findings demonstrated that impaired renal function was independently associated with a higher degree of calcification in intracranial arteries, especially medial calcification, which reflects a distinction between two types of arterial calcification and raise the possibility for specific prevention of lesion formation.

Serum biomarkers for arterial calcification in humans: A systematic review

Aim

To clarify the role of mediators of ectopic mineralization as biomarkers for arterial calcifications.

Methods

MEDLINE and Embase were searched for relevant literature, until January 4th 2022. The investigated biomarkers were: calcium, phosphate, parathyroid hormone, vitamin D, pyrophosphate, osteoprotegerin, receptor activator of nuclear factor-kappa B ligand (RANKL), fibroblast growth factor-23 (FGF-23), Klotho, osteopontin, osteocalcin, Matrix Gla protein (MGP) and its inactive forms and vitamin K. Studies solely performed in patients with kidney insufficiency or diabetes mellitus were excluded.

Results

After screening of 8985 articles, a total of 129 articles were included in this systematic review. For all biomarkers included in this review, the results were variable and more than half of the studies for each specific biomarker had a non-significant result. Also, the overall quality of the included studies was low, partly as a result of the mostly cross-sectional study designs. The largest body of evidence is available for phosphate, osteopontin and FGF-23, as a little over half of the studies showed a significant, positive association. Firm statements for these biomarkers cannot be drawn, as the number of studies was limited and hampered by residual confounding or had non-significant results. The associations of the other mediators of ectopic mineralization with arterial calcifications were not clear.

Conclusion

Associations between biomarkers of ectopic mineralization and arterial calcification are variable in the published literature. Future longitudinal studies differentiating medial and intimal calcification could add to the knowledge of biomarkers and mechanisms of arterial calcifications.

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We researched the association between biomarkers and arterial calcifications.

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This review focused on biomarkers of bone metabolism and Matrix Gla protein.

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Associations between biomarkers and arterial calcification are variable.

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Future studies should differentiate between medial and intimal calcifications.

Genetically predicted phosphate and cardiovascular disease: A Mendelian randomization study

Background

Extensive epidemiological studies have highlighted the correlation between serum phosphate and cardiovascular diseases. The present study aims to determine whether genetically predicted serum phosphate is causally associated with the distinct subtypes of cardiovascular events through the use of Mendelian randomization (MR) analysis.

Methods

Independent and strongly correlated single-nucleotide polymorphisms (SNPs) for serum phosphate were extracted from publicly available genome-wide association studies. Summary statistics of cardiovascular diseases were derived from large-scale consortiums, including HERMES and FinnGen biobank. MR-Egger, weighted median, inverse variance weighted, pleiotropy residual sum and outlier (MR-PRESSO) methods and MR using robust adjusted profile score (MR-RAPS) were employed to analyze causality. The sensitivity analyses comprised heterogeneity, horizontal pleiotropy, and leave-one-out approaches; these were used to ensure the stability of the results.

Results

Our study demonstrated that increased genetically predicted serum phosphate is causally associated with a higher risk of valvular heart disease (VHD) [For VHD including rheumatic fever: odds ratio (OR) = 2.45; 95% confidence interval (CI), 1.52-3.94; p = 0.0002; for non-rheumatic VHD: OR = 6.58; 95% CI, 2.50-17.32; p = 0.0001]. However, no causal association was detected between serum phosphate and other common cardiovascular diseases (including coronary heart disease, heart failure, atrial fibrillation, and essential hypertension).

Conclusions

The results indicate strong causality between serum phosphate and valvular heart disease. Serum phosphate-lowering therapy within the physiological range may represent a novel therapeutic method for valvular heart disease.

Plasma Calcium and Phosphorus Levels and Cardiovascular Disease Risks in Egyptian Type 2 Diabetic Patients

Background: Cardiovascular complication of diabetes is considered an important issue that needs deep investigations. The levels of plasma calcium (Ca) and phosphorus (P) have been implicated as having an association to cardiovascular diseases. AIM: The objective of the present research was to study the plasma levels of both Ca and P and their association to the atherogenic ratio; total cholesterol: high density lipoprotein-cholesterol and the plasma albumin in male and female patients with type 2-diabetes. The interrelation between anthropometric parameters represented by body mass index (BMI), waist circumference and waist/hip ratio with Ca and P were studied. Also, the association between plasma Ca and P with their dietary intake were investigated. Subjects and METODS: Thirty-one type 2-diabetic male and female patients participated in the study, in addition of ten healthy subjects. Biochemical parameters, anthropometric measurements and nutrients′ intake were assessed. Biochemical parameters include plasma Ca, P, lipid profile, albumin, liver function tests and creatinine. RESULTS: Plasma Ca levels of female patients of BMI> 30 kg/m2 demonstrated significant increase compared to the control group.  All male and female patients showed significant increase in plasma P compared to the control group. Glycosylated hemoglobin of male and females showed significant high values compared to the control group except for diabetic male of BMI>30 kg/m2 that showed insignificant increase. No significant changes in plasma TG and LDL-C levels were noticed compared to the control.  Plasma TC of patients showed significant high levels compared to the control group. The levels of HDL-C of patients were significantly lower than that of the control. The ratios of TC/HDL-C diabetic patients either male or female and whatever their BMI were significantly higher than that of the control. No significant changes in plasma activities of ALT and AST and bilirubin levels were observed among the different groups including the control.  Plasma albumin levels demonstrated significant reduction compared to the control group whatever their sexes or BMI. Plasma creatinine levels of the different diabetic groups showed insignificant change from the control group except for the male group of BMI<30 kg/m2 that showed significant elevation. In male, plasma Ca showed significant negative correlation with albumin and positive correlation with creatinine and dietary vitamin D. In female, a significant positive correlation was noticed between plasma and dietary P while a negative correlation was observed between plasma Ca and dietary iron. CONCLUSION: Elevated of plasma P together with reduced plasma albumin and elevated TC/HDL-C may reflect an association of plasma P to CVD in male and female diabetic subjects while high plasma Ca might predict CVD in only female diabetic patients of BMI > 30 kg/m2.

The Mutual Contribution of 3-NT, IL-18, Albumin, and Phosphate Foreshadows Death of Hemodialyzed Patients in a 2-Year Follow-Up

Patients with chronic kidney disease (CKD), especially those who are hemodialyzed (HD), are at significantly high risk of contracting cardiovascular disease and having increased mortality. This study aimed to find potential death predictors, the measurement of which may reflect increased mortality in HD patients, and then combine the most promising ones in frames of a simple death risk assessment model. For this purpose, HD patients (n=71) with acute myocardial infarction in the last year (HD group) and healthy people (control group) as a comparative group (n=32) were included in the study. Various laboratory determinations and non-invasive cardiovascular tests were performed. Next, patients were followed for two years, and data on cardiovascular (CV) deaths were collected. On this basis, two HD groups were formed: patients who survived (HD-A, n=51) and patients who died (HD-D, n=20). To model HD mortality, 21 out of 90 potential variables collected or calculated from the raw data were selected. The best explanatory power (95.5%) was reached by a general linear model with four variables: interleukin 18, 3-nitrotyrosine, albumin, and phosphate. The interplay between immuno-inflammatory processes, nitrosative and oxidative stress, malnutrition, and calcium-phosphate disorders has been indicated to be essential in predicting CV-related mortality in studied HD patients. ClinicalTrials.gov Identifier: NCT05214872.

Hyperphosphatemia and Cardiovascular Disease

Hyperphosphatemia or even serum phosphate levels within the “normal laboratory range” are highly associated with increased cardiovascular disease risk and mortality in the general population and patients suffering from chronic kidney disease (CKD). As the kidney function declines, serum phosphate levels rise and subsequently induce the development of hypertension, vascular calcification, cardiac valvular calcification, atherosclerosis, left ventricular hypertrophy and myocardial fibrosis by distinct mechanisms. Therefore, phosphate is considered as a promising therapeutic target to improve the cardiovascular outcome in CKD patients. The current therapeutic strategies are based on dietary and pharmacological reduction of serum phosphate levels to prevent hyperphosphatemia in CKD patients. Large randomized clinical trials with hard endpoints are urgently needed to establish a causal relationship between phosphate excess and cardiovascular disease (CVD) and to determine if lowering serum phosphate constitutes an effective intervention for the prevention and treatment of CVD.

Hyperphosphatemia rather than hypophosphatemia indicates a poor prognosis in patients with sepsis

BACKGROUND

Sepsis is the leading cause of hospitalization and death in the intensive care unit. It is vital to identify high-risk patients with poor prognosis in the early stages of sepsis. We aimed to investigate the prognostic value of serum phosphorus levels for sepsis.

METHODS

The data of 4767 patients with sepsis were collected from the Multiparameter Intelligent Monitoring in Intensive Care III database. The Locally Weighted Scatterplot Smoothing technique and Kaplan-Meier analysis were used to test the crude relationship between serum phosphorus levels and mortality or overall survival. The multivariable logistic regression was used to further analyze the relationship between serum phosphorus levels and in-hospital mortality. The subgroup analysis was performed according to renal failure, use of vasopressin and the Sequential Organ Failure Assessment (SOFA) score.

RESULTS

Only hyperphosphatemia significantly correlated with in-hospital mortality [odds ratio (OR) 1.48; 95% confidence interval (CI) 1.19-1.85], while the correlation between hypophosphatemia and in-hospital mortality was not significant (OR 0.91; 95% CI 0.70-1.19). The interactions between serum phosphorus and renal failure, use of vasopressin or the SOFA score were not significant.

CONCLUSIONS

Hyperphosphatemia rather than hypophosphatemia indicates a poor prognosis in patients with sepsis.