Serum alkaline phosphatase is associated with arterial stiffness and 10-year cardiovascular disease risk in a Chinese population

Predicting life span of type 2 diabetes patients through alkaline phosphatase and vitamin D: Results from NHANES 1999-2018

BACKGROUND AND AIMS

Disparities in serum biomarker levels related to mortality persist within the US diabetic population. We conducted a study to explore the impact of alkaline phosphatase (ALP) on all-cause mortality and cardiovascular disease (CVD) mortality in type 2 diabetes patients.

METHODS

We analyzed a nationally representative sample of individuals aged 20 years and above from the National Health and Nutrition Examination Survey (NHANES) conducted in the United States between 1999 and 2018. Baseline demographic information and biochemical markers, including blood glucose, γ-glutamyltranspeptidase, vitamin D and albumin, were collected. Participants were divided into four groups based on ALP levels and linked to the National Death Index to assess mortality. Follow-up continued until December 2019, and multiple mediation analyses were performed to assess the combined impact of different indicators on ALP differences in all-cause mortality and cardiovascular mortality risk.

RESULTS

Our analysis included 6481 NHANES participants, categorized as follows: 1626 (21.9%) had ALP levels below 58 U/L, 1674 in the second quartile (58-72 U/L), 1569 in the third quartile (72-88.3 U/L), and 1612 in the fourth quartile (above 88.3U/L). Significantly higher all-cause mortality and cardiovascular mortality rates were observed among participants in the 4th ALP quartile compared to other levels. The all-cause mortality rate was 38.06 per 1000 person-years (95% CI 34.89-41.51), and the cardiovascular mortality rate was 10.67 (9.06-12.57). Mediation analysis indicated that Vitamin D and albumin played a mediating role in the association between all-cause mortality, cardiovascular mortality, and ALP levels, with mediation proportions ranging from 10.33% to 27.64%.

CONCLUSIONS

Our study suggests that ALP levels have clinical value in predicting all-cause and CVD mortality risk in T2DM patients. The upregulation of Vitamin D and albumin might play a significant role in improving risk prediction and enable targeted interventions for reducing mortality risk in this population.

Aortic mineralization triggers the risk of acute type B aortic dissection

BACKGROUND AND AIMS

The role of aortic mineralization in the pathogenesis of acute type B aortic dissection (TBAD) is unclear. Whether thoracic aortic calcification (TAC) and circulating alkaline phosphatase (ALP) activity are associated with acute TBAD risk remains elusive.

METHODS

Observational and Mendelian randomization (MR) studies were conducted sequentially. Using propensity score matching (1:1) by age and sex, patients with acute TBAD (n = 125) were compared with control patients (n = 125). Qualitative (score) and quantitative (volume) analyses of the TAC burden on different thoracic aortic segments were conducted using non-enhanced computed tomography. Univariate and multivariate analyses were used to identify significant independent risk factors for TBAD and TAC burden, respectively. MR was finally used to determine the causal relationship between elevated ALP activity and TBAD risk.

RESULTS

The qualitative and quantitative analyses revealed that TAC burden was significantly higher in the TBAD group, except for in the ascending aortic segment (both p < 0.05). Preoperative circulating ALP was significantly elevated in the TBAD group (p < 0.001). The elevated TAC burden score on the descending thoracic aortic segment (odds ratio [OR] 3.31, 95% confidence interval [CI] 1.31-8.37) and increased ALP activity (OR 1.03, 95% CI 1.01-1.06) was independently associated with TBAD risk. Interestingly, ALP was significantly positively associated with TAC burden, and MR analyses confirmed that ALP genetically predicted TBAD risk.

CONCLUSIONS

Elevated ALP may trigger TBAD risk via the increased volume of TAC. Aortic mineralization may not protect the aorta itself.

Role of serum alkaline phosphatase as a potential biomarker of severity and prognosis in intracerebral hemorrhage

OBJECTIVES

Alkaline phosphatase (ALP) catalyzes the hydrolysis of pyrophosphate and facilitates vascular calcification. We aimed at investigating serum ALP levels in intracerebral hemorrhage (ICH) patients and ascertaining its relationship to severity and prognosis.

METHODS

Serum ALP levels from 148 patients and 148 healthy controls were detected. Glasgow coma scale (GCS) score and hematoma volume at admission were recorded to evaluate hemorrhagic severity. Modified Rankin Scale (mRS) score > 2 at 90 days after onset was judged as a poor prognosis.

RESULTS

Serum ALP levels in patients with ICH were substantially elevated compared with healthy controls, and were significantly related to hematoma volume and GCS score. Serum ALP levels significantly distinguished ICH patients at risk for unfavorable prognosis. Serum ALP levels > 78.5 U/L in ICH patients may indicated a unfavorable prognosis with 69.1 % sensitivity and 83.6 % specificity, and served as an independent predictor for unfavorable prognosis.

CONLUSIONS

Elevated serum ALP levels were intimately connected with increased severity and 90-day unfavorable prognosis in patients with ICH. Serum ALP could be a potential biomarker for severity and prognosis of ICH.

Positive association between alkaline phosphatase and arteriosclerosis: a cross-sectional study

AIMS

Serum alkaline phosphatase (ALP) is known to be associated with cardiovascular events and cerebral arteriosclerosis. However, the link between ALP and early arteriosclerosis remains unclear. This study investigated the relationship between ALP and early arteriosclerosis assessed by brachial-ankle pulse wave velocity (Ba-PWV).

METHODS

This retrospective analysis included 5011 participants who underwent health examinations, including ALP and Ba-PWV measurement, at the Second Hospital of Hebei Medical University from 2012 to 2017. Regression analysis, smoothing function analysis in the generalized additive model (GAM), threshold effect analysis, and subgroup analyses were performed.

RESULTS

Multivariate regression analysis identified a significantly positive association between serum ALP and arteriosclerosis [odds ratio (OR) = 1.008, 95% confidence interval (CI) 1.004-1.011, P  < 0.001]. Smoothing function analysis indicated a two-stage association between ALP and arteriosclerosis. Furthermore, threshold effect analysis determined an inflection point at 135 U/l, below which the relationship was linearly positive and above which the risk of arteriosclerosis did not increase prominently with increasing ALP (OR = 1.009, 95% CI: 1.005-1.013, P  < 0.001; OR = 0.976, 95% CI: 0.952-1.002, P  = 0.068). However, ALP was not associated with arteriosclerosis only in participants with diabetes (OR = 0.996, 95% CI: 0.979-1.014, P  = 0.690). A positive association between Ba-PWV and arteriosclerosis was observed for both the arteriosclerosis and nonarteriosclerosis groups ( β  = 9.10, 95% CI: 4.67-13.54, P  < 0.001; β  = 8.02, 95% CI: 5.67-10.37, P  < 0.001).

CONCLUSION

In this study, the serum ALP level was positively associated with early arteriosclerosis, with a saturation effect beyond ALP = 135 U/l. However, the positive association between ALP and arteriosclerosis was unclear in adults with diabetes.

Associations Between Atherosclerosis and Elevated Serum Alkaline Phosphatase in Patients With Coronary Artery Disease in an Inflammatory State

BACKGROUND AND AIM

Serum alkaline phosphatase (ALP) has been shown to be associated with cardiovascular disease (CVD) risk. Inflammation is the initiator of atherosclerosis, throughout the life of atherosclerosis. This study investigated the relationship between serum ALP and atherosclerosis in patients with coronary artery disease (CAD) in an inflammatory state.

METHODS

This was a multicentre retrospective study including 22,989 patients with CAD. Serum alkaline phosphatase was converted into the quartiles. C-reactive protein (CRP) was assayed as a marker of systemic inflammation. The atherosclerosis index (AI) was used to assess the degree of atherosclerosis. Binary logistic regression was used to analyse the relationship between ALP and AI. Stratified analysis was performed according to sex and age.

RESULTS

Elevated serum ALP was associated with the risk of atherosclerosis in patients with CAD, and after quartiling ALP, the OR for Q4 was 1.17 (95% CI 1.08-1.26; p<0.001) when using Q1 as reference. The odds ratio (OR) for ALP and risk of atherosclerosis was higher in patients aged ≤60 years (OR 1.33, 95% CI 1.15-1.53; p<0.001) than in patients aged >60 years (OR 1.11, 95% CI 1.01-1.23; p<0.05), and higher in males (OR 1.21, 95% CI 1.09-1.35; p<0.001) than in females (OR 1.16, 95% CI 1.03-1.31; p<0.05). Q4 (ALP >83.00 U/L) was significantly associated with increased risk of atherosclerosis in the inflammatory state (OR 1.48, 95% CI 1.18-1.86; p<0.001), and it remained after stratified analysis according to sex and age.

CONCLUSIONS

The risk of atherosclerosis tended to increase with increasing ALP levels and the correlation between ALP and the degree of atherosclerosis was significantly stronger when ALP was >83.00 U/L. This relationship was more pronounced in inflammatory states, and there were sex and age differences.

REGISTRATION

URL: https://www.

CLINICALTRIALS

gov; Unique identifier: NCT04026724.

Alkaline Phosphatase: An Old Friend as Treatment Target for Cardiovascular and Mineral Bone Disorders in Chronic Kidney Disease

Alkaline phosphatase (ALP) is an evolutionary conserved enzyme and widely used biomarker in clinical practice. Tissue-nonspecific alkaline phosphatase (TNALP) is one of four human isozymes that are expressed as distinct TNALP isoforms after posttranslational modifications, mainly in bone, liver, and kidney tissues. Beyond the well-known effects on bone mineralization, the bone ALP (BALP) isoforms (B/I, B1, B1x, and B2) are also involved in the pathogenesis of ectopic calcification. This narrative review summarizes the recent clinical investigations and mechanisms that link ALP and BALP to inflammation, metabolic syndrome, vascular calcification, endothelial dysfunction, fibrosis, cardiovascular disease, and mortality. The association between ALP, vitamin K, bone metabolism, and fracture risk in patients with chronic kidney disease (CKD) is also discussed. Recent advances in different pharmacological strategies are highlighted, with the potential to modulate the expression of ALP directly and indirectly in CKD–mineral and bone disorder (CKD-MBD), e.g., epigenetic modulation, phosphate binders, calcimimetics, vitamin D, and other anti-fracture treatments. We conclude that the significant evidence for ALP as a pathogenic factor and risk marker in CKD-MBD supports the inclusion of concrete treatment targets for ALP in clinical guidelines. While a target value below 120 U/L is associated with improved survival, further experimental and clinical research should explore interventional strategies with optimal risk–benefit profiles. The future holds great promise for novel drug therapies modulating ALP.

The correlation between serum total alkaline phosphatase and bone mineral density in young adults

Background

Elevated total alkaline phosphatase (T-ALP) levels are usually indicative of enhanced osteoblastic activity and bone conversion status and are thus considered as a key factor needed for fresh bone mineralization and synthesis. To date, there is no consistent conclusion on the association between the serum T-ALP levels and bone mineral density (BMD). Therefore, the present study focused on exploring the association of serum T-ALP with lumbar BMD among young adults.

Methods

The present cross-sectional study included 6,331 subjects included in the National Health and Nutrition Examination Survey (NHANES) during 2011–2016. The participants aged 20–40 years included 3,349 males and 2,982 females. Serum T-ALP was our main variable, lumbar BMD was our outcome variable, and additional variables were the possible impact modifiers. The relations were analysed by the trend study, weighted multiple linear regression models, smooth curve fitting, and stratified analyses.

Results

In a completely corrected multiple regression model, a negative association between serum T-ALP and lumbar BMD was discovered (β = -0.0007, 95% CI: –0.0009– –0.0005, P < 0.000001). After converting the continuous variable serum T-ALP into the categorical one, the significant negative association was still observed (P < 0.001), and in the subgroup and smooth curve fitting analyses, this negative correlation remained significant, too.

Conclusions

Our study results indicated that serum T-ALP was negatively associated with lumbar BMD among young adults. Serum T-ALP measurement in the near future might become an effective biomarker to diagnose and treat osteoporosis on time.