The Interplay Between the Renin-Angiotensin-Aldosterone System and Parathyroid Hormone

Challenging treatment of severe hypotension following tracheal intubation in a patient with primary hyperparathyroidism: A case report

RATIONALE

Primary hyperparathyroidism (PHPT), which is characterized by increased parathyroid hormone secretion, typically manifests as hypercalcemia and hypertension. Here, we report a case of severe hypotension following tracheal intubation during anesthesia induction in a patient with PHPT, in contrast to the expected hypertensive response.

PATIENT CONCERNS

A 52-year-old man presented with nausea after eating, leg pain when walking, and headaches.

DIAGNOSIS

Based on the blood test and computed tomography results, he was diagnosed with PHPT.

INTERVENTIONS

The patient underwent parathyroidectomy under general anesthesia. After induction anesthesia and tracheal intubation, severe acute hypotension and tachycardia suddenly developed. To treat hypotensive shock, we immediately administered ephedrine and phenylephrine and infused Ringer solution.

OUTCOMES

The symptoms of hypotensive shock were alleviated by this intervention.

LESSONS

We speculate that the cause of his severe hypotension was vasodilation due to the transient release of parathyroid hormone from mechanical stimulation by anesthetic procedures, such as tracheal intubation, combined with hypercalcemia-induced severe dehydration. Moreover, we speculate that fluid resuscitation stabilized his condition and helped achieve a successful surgical outcome. The possibility of severe hypotension after anesthesia induction should be anticipated, and management of cases with severe dehydration should be optimized during the anesthetic management of patients with PHPT.

Corticosteroid rhythms in hypoparathyroid patients

OBJECTIVE

Previous studies indicate a possible bidirectional stimulatory relationship between parathyroid hormone (PTH) and adrenocortical hormones, but the pattern of adrenocortical secretion in hypoparathyroidism is unknown. We aimed to characterize the adrenocortical secretion in patients with postsurgical hypoparathyroidism, and whether continuous subcutaneous PTH (1-34) infusion alters secretion patterns.

DESIGN

Crossover interventional study.

METHODS

We recruited 10 patients with postsurgical hypoparathyroidism with very low PTH levels on stable treatment with active vitamin D and calcium. Cortisol, cortisone, and aldosterone levels were measured in microdialysate from subcutaneous tissue over 24 h, before and during continuous subcutaneous PTH (1-34) infusion. Cortisol was also assayed in serum, saliva, and urine, and aldosterone and ACTH in serum and plasma, respectively. Ten patients with primary hyperparathyroidism and 10 healthy volunteers matched for sex and age served as controls.

RESULTS

Hypoparathyroid patients displayed both ultradian and circadian rhythmicity for tissue cortisol, cortisone, and aldosterone. Tissue aldosterone and cortisone levels were significantly lower in hypoparathyroid patients than in healthy controls, with no difference in tissue cortisol, but a higher cortisol to cortisone ratio. Treatment with PTH (1-34) increased tissue levels of aldosterone, cortisol, and cortisone and reduced the ratio of cortisol to cortisone.

CONCLUSION

Adrenocortical hormone levels are reduced in postsurgical hypoparathyroidism, and partly restored by short-term continuous subcutaneous PTH (1-34) therapy.

CLINICAL TRIAL REGISTRATION NUMBER

NCT02986607.

Slow-Reflow and Prognosis in Patients with High Parathyroid Hormone Levels Undergoing Primary Percutaneous Coronary Intervention for Acute ST-Segment Elevation Myocardial Infarction

We aimed to evaluate the correlation among serum parathyroid hormone (PTH) and slow-reflow during primary percutaneous coronary intervention (PCI) and prognosis in patients with ST-segment elevation myocardial infarction (STEMI). A total of 262 patients were enrolled and divided into a slow-reflow group (n = 61) and a control group (n = 201). PTH was an independent risk factor for slow-reflow (P < 0.05), and the regression model had good discrimination and calibration. ROC curve analysis showed that PTH (≥ 63.65 pg/ml) had a predictive value for slow-reflow (P < 0.001). During the 1-year follow-up, the patients were divided into a PTH-h group (≥ 63.65 pg/ml, n = 100) and a PTH-l group (< 63.65 pg/ml, n = 162). Readmission for HF was independently associated with PTH levels (P < 0.05). KM survival analysis suggested that PTH-h had a predictive value for MACEs, especially for readmission for HF (P < 0.05). PTH levels were associated with slow-reflow during PCI and MACEs during follow-up in patients with STEMI.

Planting the Seed for Blood Pressure Control: The Role of Plant-Based Nutrition in the Management of Hypertension

PURPOSE OF REVIEW

Hypertension results in significant morbidity, mortality, and healthcare expenditures. Fortunately, it is largely preventable and treatable by implementing dietary interventions, though these remain underutilized. Here, we aim to explore the role of healthy dietary patterns in hypertension management and describe approaches for busy clinicians to address nutrition effectively and efficiently with patients.

RECENT FINDINGS

DASH, Mediterranean, vegetarian, and vegan diets that include minimally processed, plant-based foods as core elements have consistently shown positive effects on hypertension. Recommendations that distill the most healthful components of these diets can significantly impact patient outcomes. Clinicians can harness evidence-based dietary assessment and counseling tools to implement and support behavioral changes, even during brief office visits. Healthful plant-based dietary patterns can often effectively prevent and treat hypertension. Clinicians may help improve patient outcomes by discussing evidence-based nutrition with their patients. Future work to promote infrastructural change that supports incorporating evidence-based nutrition into medical education, clinical care, and society at large can support these efforts.

Association of parathyroid hormone with risk of hypertension and type 2 diabetes: a dose-response meta-analysis

BACKGROUND

Despite an increase in parathyroid hormone (PTH) has been reported to be associated with a higher risk of hypertension and type 2 diabetes (T2D), the comprehensive evaluation of the dose-response relationship between PTH and hypertension and T2D remains ambiguous. Therefore, a dose-response meta-analysis was performed to quantitatively investigate this association.

METHODS

PubMed, Web of Science, and Embase were systematically searched up to May 2023. Random-effect models were used to estimate the summary odds ratios (ORs) and 95% confidence intervals (CIs). Restricted cubic splines were used to model the dose-response association.

RESULTS

Ten articles (including 13 studies) were identified, with a total of 11,878 cases and 51,234 participants in the meta-analysis. Of these studies, eight (five cohort and three cross-sectional) studies investigated the association of PTH with hypertension; five (two cohort and three cross-sectional) studies assessed the association of PTH with T2D. The results showed a positive relationship between PTH and the risk of hypertension (OR,1.24, 95% CI: 1.16-1.33). We found a linear association between PTH and hypertension (Pnon-linearity= 0.222). In the dose-response analysis, the risk of hypertension increased 5% for every 10 pg/ml increase in PTH (OR,1.05, 95% CI: 1.02-1.08). The pooled OR of T2D risk for a 10 pg/ml increase in PTH was 1.00 (95% CI: 0.98-1.02).

CONCLUSIONS

Elevated PTH is associated with an increased risk of hypertension. However, the evidence of the association between PTH and T2D is limited, and more well-designed studies need to be explored.

The prevalence of primary and secondary hyperparathyroidism and its cardiometabolic implications in primary aldosteronism

BACKGROUND

The aim of this study was to analyze the prevalence of primary and secondary hyperparathyroidism in patients with primary aldosteronism (PA), and its implication on cardiovascular and metabolic outcomes.

METHODS

A retrospective study of patients with PA (exposed cohort, N.=44) and all hypertensive (EH) patients with adrenal lesions without PA nor other adrenal hypersecretion (non-exposed cohort, N.=41) on follow-up at our center between 2016 and 2020.

RESULTS

The mean age of patients with PA and EH was 55.1±14.13 and 66.3±10.93 (P<0.001), and 50% of PA and 39.0% of EH were women (P=0.309). At diagnosis, the prevalence of primary hyperparathyroidism in PA was of 18.2%, and all were normocalcemic hyperparathyroidism cases. Globally, no differences were found in the prevalence of primary hyperparathyroidism compared to EH (18.2% vs. 29.3%, P=0.229), but hypercalcemic primary hyperparathyroidism was significantly more prevalent in EH patients than in PA (22.0% vs. 0%, P=0.001). There were 47.7% (N.=21) cases of secondary hyperparathyroidism in patients with PA (4 due to chronic kidney disease (CKD) and vitamin D deficiency, and 17 due to vitamin D deficiency alone). The cardiometabolic profile of patients with PA and hyperparathyroidism (N.=29) was similar to of those patients without hyperparathyroidism (N.=15) at diagnosis and after a median follow-up of 3.6 years (interquartile range 1.1-5.9).

CONCLUSIONS

Although primary and secondary hyperparathyroidism are common in patients with PA, their prevalence was similar than the observed in EH patients. Primary hyperparathyroidism is usually mild in PA, appearing as normocalcemic forms. No negative implications of the hyperparathyroidism in the cardiometabolic profile of PA were observed.

Unmasking the complex roles of hypocalcemia in cancer, COVID-19, and sepsis: Engineered nanodelivery and diagnosis

Calcium (Ca2+) homeostasis is essential for maintaining physiological processes in the body. Disruptions in Ca2+ signaling can lead to various pathological conditions including inflammation, fibrosis, impaired immune function, and accelerated senescence. Hypocalcemia, a common symptom in diseases such as acute respiratory distress syndrome (ARDS), cancer, septic shock, and COVID-19, can have both potential protective and detrimental effects. This article explores the multifaceted role of Ca2+ dysregulation in inflammation, fibrosis, impaired immune function, and accelerated senescence, contributing to disease severity. Targeting Ca2+ signaling pathways may provide opportunities to develop novel therapeutics for age-related diseases and combat viral infections. However, the role of Ca2+ in viral infections is complex, and evidence suggests that hypocalcemia may have a protective effect against certain viruses, while changes in Ca2+ homeostasis can influence susceptibility to viral infections. The effectiveness and safety of Ca2+ supplements in COVID-19 patients remain a subject of ongoing research and debate. Further investigations are needed to understand the intricate interplay between Ca2+ signaling and disease pathogenesis.

Angiotensin receptor blockers, but not angiotensin-converting enzyme inhibitors, inhibit abnormal bone changes in spondyloarthritis

Spondyloarthritis (SpA) is a chronic inflammatory disease that results in bone ankylosis. The tissue renin-angiotensin system (RAS) is an emerging pathway potentially implicated in SpA-associated bone changes. The aim of the present study was to determine the mechanisms underlying this relationship. Sakaguchi (SKG) mice injected with curdlan (SKGc), animal models for SpA, were treated with RAS modulators, angiotensin II receptor blockers (ARBs) or angiotensin-converting enzyme inhibitors (ACEis). Disease activity was assessed using clinical scores and computed tomography scans. Mouse primary bone marrow monocytes (BMMs), osteoblast (OB) progenitor cells, peripheral blood monocytes (PBMCs), and bone-derived cells (BdCs) from patients with radiographic axial SpA (r-axSpA) were used to investigate the role of RAS in SpA pathogenesis. The expression of RAS components was significantly increased in SKGc mouse joints, and ARBs significantly reduced erosion and systemic bone loss, whereas ACEis did not. Osteoclast (OC) differentiation from primary BMMs, mediated by TRAF6, was inhibited by ARBs but promoted by ACEis; the modulators also exerted opposite effects on OB differentiation. Expression of RAS molecules was higher in PBMCs and BdCs of patients with r-axSpA than in control participants. ARBs inhibited OB differentiation in the BdCs of patients with r-axSpA, whereas ACEis did not. Neither ARBs nor ACEis affected OB differentiation in the control participants. In SpA, a condition characterized by RAS overexpression, ARBs, but not ACEis, inhibited OC and OB differentiation and bone progression. The findings should be taken into account when treating patients with SpA using RAS modulators.

The Relationship between Renin-Angiotensin-Aldosterone System (RAAS) Activity, Osteoporosis and Estrogen Deficiency in Type 2 Diabetes

Type 2 diabetes (T2D) is associated with a plethora of comorbidities, including osteoporosis, which occurs due to an imbalance between bone resorption and formation. Numerous mechanisms have been explored to understand this association, including the renin-angiotensin-aldosterone system (RAAS). An upregulated RAAS has been positively correlated with T2D and estrogen deficiency in comorbidities such as osteoporosis in humans and experimental studies. Therefore, research has focused on these associations in order to find ways to improve glucose handling, osteoporosis and the downstream effects of estrogen deficiency. Upregulation of RAAS may alter the bone microenvironment by altering the bone marrow inflammatory status by shifting the osteoprotegerin (OPG)/nuclear factor kappa-Β ligand (RANKL) ratio. The angiotensin-converting-enzyme/angiotensin II/Angiotensin II type 1 receptor (ACE/Ang II/AT1R) has been evidenced to promote osteoclastogenesis and decrease osteoblast formation and differentiation. ACE/Ang II/AT1R inhibits the wingless-related integration site (Wnt)/β-catenin pathway, which is integral in bone formation. While a lot of literature exists on the effects of RAAS and osteoporosis on T2D, the work is yet to be consolidated. Therefore, this review looks at RAAS activity in relation to osteoporosis and T2D. This review also highlights the relationship between RAAS activity, osteoporosis and estrogen deficiency in T2D.

Impact of the gut microbiota on angiotensin Ⅱ-related disorders and its mechanisms

The renin-angiotensin system (RAS) consists of multiple angiotensin peptides and performs various biological functions mediated by distinct receptors. Angiotensin II (Ang II) is the major effector of the RAS and affects the occurrence and development of inflammation, diabetes mellitus and its complications, hypertension, and end-organ damage via the Ang II type 1 receptor. Recently, considerable interest has been given to the association and interaction between the gut microbiota and host. Increasing evidence suggests that the gut microbiota may contribute to cardiovascular diseases, obesity, type 2 diabetes mellitus, chronic inflammatory diseases, and chronic kidney disease. Recent data have confirmed that Ang II can induce an imbalance in the intestinal flora and further aggravate disease progression. Furthermore, angiotensin converting enzyme 2 is another player in RAS, alleviates the deleterious effects of Ang II, modulates gut microbial dysbiosis, local and systemic immune responses associated with coronavirus disease 19. Due to the complicated etiology of pathologies, the precise mechanisms that link disease processes with specific characteristics of the gut microbiota remain obscure. This review aims to highlight the complex interactions between the gut microbiota and its metabolites in Ang II-related disease progression, and summarize the possible mechanisms. Deciphering these mechanisms will provide a theoretical basis for novel therapeutic strategies for disease prevention and treatment. Finally, we discuss therapies targeting the gut microbiota to treat Ang II-related disorders.

Evaluating the clinical and mechanistic effects of eplerenone and amiloride monotherapy, and combination therapy with cinacalcet, in primary hyperparathyroidism: A placebo-controlled randomized trial

OBJECTIVES

Human physiology and epidemiology studies have demonstrated complex interactions between the renin-angiotensin-aldosterone system, parathyroid hormone and calcium homeostasis. Several of these studies have suggested that aldosterone inhibition may lower parathyroid hormone (PTH) levels. The objective of this study was to assess the effect of 4 weeks of maximally tolerated mineralocorticoid receptor antagonist therapy with eplerenone on PTH levels in patients with primary hyperparathyroidism (P-HPT) when compared to amiloride and placebo. We also investigated the synergistic effect of these interventions when combined with cinacalcet for an additional 2 weeks.

DESIGN

Randomized, double-blinded, three parallel-group, placebo-controlled trial.

PATIENTS

Patients with P-HPT.

RESULTS

Most patients were women (83%) and White (76%). Maximally tolerated doses of eplerenone and amiloride induced significant reductions in blood pressure and increases in renin and aldosterone production; however, despite these physiologic changes, neither intervention induced significant changes in PTH or calcium levels when compared to the placebo. Both eplerenone and amiloride therapy induced significant reductions in procollagen type 1 N-terminal propeptide levels when compared to placebo. When cinacalcet therapy was added, PTH and calcium levels were markedly reduced in all groups; however, there was no significant difference in PTH or serum calcium reductions between groups.

CONCLUSIONS

Although maximally tolerated therapy with eplerenone and amiloride induced expected changes in renin, aldosterone and blood pressure, there were no meaningful changes in PTH or serum calcium levels in P-HPT patients. These results suggest that inhibition of aldosterone action does not have a clinically meaningful role in medical therapy for P-HPT.

The preliminary study on cardiac structure and function in Chinese patients with primary hyperparathyroidism

PURPOSE

Recent evidences show that primary hyperparathyroidism (PHPT) patients have a high prevalence of cardiovascular diseases. However, the reported changes in cardiac status are inconsistent in previous studies. The present work evaluated the cardiac structure and function in PHPT patients by echocardiography.

METHODS

PHPT patients and age- and sex-matched healthy controls were enrolled in this case-control study. Biochemical parameters were retrospectively collected from PHPT patients. Cardiac function and structure were assessed in all subjects using echocardiography.

RESULTS

A total of 153 PHPT patients and 51 age- and sex-matched healthy controls were enrolled in this study. The mean serum calcium and parathyroid hormone (PTH) levels in PHPT patients were 2.84 ± 0.28mmol/L and 206.9 (130.0, 447.5) pg/ml, respectively. Left ventricular ejection fraction (LVEF) and early to late mitral annular velocity (E/A) were significantly lower in PHPT patients than in healthy controls (68.2 ± 6.0 vs. 70.7 ± 16.7%, 1.0 ± 0.5 vs. 1.4 ± 0.5, respectively, p both < 0.05). The left ventricular mass index (LVMI) and the relative wall thickness (RWT) were not significantly different between the two groups. However, the difference in LVEF between PHPT patients without hypertension and diabetes and the control groups disappeared. The majority of PHPT patients had normal cardiac geometry; however, a proportion of them exhibited concentric remodeling (normal LVMI, RWT≥0.42). Serum calcium, corrected calcium, ionized calcium and PTH were inversely related to E/A, whereas serum phosphorus and 24-hour urine calcium were positively related to E/A. Furthermore, biochemical parameters were not correlated with LVEF.

CONCLUSIONS

These findings demonstrate that PHPT patients exhibit diastolic cardiac dysfunction reflected by decreased E/A, as well as possible cardiac structural abnormalities. The serum calcium, phosphorus, and parathyroid hormone levels may influence cardiac structure and function.

Epidemiology, Pathophysiology, and Genetics of Primary Hyperparathyroidism

In this narrative review, we present data gathered over four decades (1980-2020) on the epidemiology, pathophysiology and genetics of primary hyperparathyroidism (PHPT). PHPT is typically a disease of postmenopausal women, but its prevalence and incidence vary globally and depend on a number of factors, the most important being the availability to measure serum calcium and parathyroid hormone levels for screening. In the Western world, the change in presentation to asymptomatic PHPT is likely to occur, over time also, in Eastern regions. The selection of the population to be screened will, of course, affect the epidemiological data (ie, general practice as opposed to tertiary center). Parathyroid hormone has a pivotal role in regulating calcium homeostasis; small changes in extracellular Ca++ concentrations are detected by parathyroid cells, which express calcium-sensing receptors (CaSRs). Clonally dysregulated overgrowth of one or more parathyroid glands together with reduced expression of CaSRs is the most important pathophysiologic basis of PHPT. The spectrum of skeletal disease reflects different degrees of dysregulated bone remodeling. Intestinal calcium hyperabsorption together with increased bone resorption lead to increased filtered load of calcium that, in addition to other metabolic factors, predispose to the appearance of calcium-containing kidney stones. A genetic basis of PHPT can be identified in about 10% of all cases. These may occur as a part of multiple endocrine neoplasia syndromes (MEN1-MEN4), or the hyperparathyroidism jaw-tumor syndrome, or it may be caused by nonsyndromic isolated endocrinopathy, such as familial isolated PHPT and neonatal severe hyperparathyroidism. DNA testing may have value in: confirming the clinical diagnosis in a proband; eg, by distinguishing PHPT from familial hypocalciuric hypercalcemia (FHH). Mutation-specific carrier testing can be performed on a proband's relatives and identify where the proband is a mutation carrier, ruling out phenocopies that may confound the diagnosis; and potentially prevention via prenatal/preimplantation diagnosis. © 2022 The Authors. Journal of Bone and Mineral Research published by Wiley Periodicals LLC on behalf of American Society for Bone and Mineral Research (ASBMR).

Genetic Parameter Estimation and Whole Sequencing Analysis of the Genetic Architecture of Chicken Keel Bending

Bone health is particularly important for high-yielding commercial layer chickens. The keel of poultry is an extension of the abdomen side of the sternum along the sagittal plane and is one of the most important bones. In this study, the keel phenotype of White Leghorns laying hen flocks showed significant individual differences. To clarify its genetic mechanism, we first estimated the heritability of keel bend (KB) in White Leghorn, recorded the production performance of the chicken flock, examined the blood biochemical indexes and bone quality in KB and keel normal (KN) chickens, and performed whole-genome pooled sequencing in KB and KN chickens. We then performed selection elimination analysis to determine the genomic regions that may affect the keel phenotypes. The results show that KB is a medium heritability trait. We found that cage height had a significant effect on the KB (p < 0.01). At 48 weeks, there were significant differences in the number of eggs, the number of normal eggs, and eggshell strength (p < 0.05). The content of parathyroid hormone was lower (p < 0.01) and that of calcitonin was higher (p < 0.01) in KB chickens than in KN chickens. The differences in bone mineral density, bone strength, and bone cortical thickness of the humerus and femur were extremely significant (p < 0.01), with all being lower in KB chickens than in KN chickens. In addition, the bones of KB chickens contained more fat organization. A total of 128 genes were identified in selective sweep regions. We identified 10 important candidate genes: ACP5, WNT1, NFIX, CNN1, CALR, FKBP11, TRAPPC5, MAP2K7, RELA, and ENSGALG00000047166. Among the significantly enriched Kyoto Encyclopedia of Genes and Genomes pathways found, we identifed two bone-related pathways, one involving “osteoclast differentiation” and the other the “MAPK signaling pathway.” These results may help us better understand the molecular mechanism of bone traits in chickens and other birds and provide new insights for the genetic breeding of chickens.

[Primary hyperparathyreoidism - diagnostic procedures and management]

Hypercalcemia as a laboratory result is often diagnosed during evaluation for osteoporosis. Any form of hypercalcemia should be evaluated further. Owing to fluctuating calcium levels, the measurement should be repeated and corrected for elevated albumin levels by calculation or by measuring ionized calcium. In the diagnosis of primary hyperparathyroidism, measurement of parathyroid hormone, creatinine/glomerular filtration rate, phosphate, 25-OH vitamin D3 and 24-hour urine values are essential for differential diagnosis. Kidney ultrasound is used to detect nephrocalcinosis or kidney stones, and dual-energy X-ray absorptiometry (DXA) to determine bone mineral density (BMD) at the lumbar spine, femoral neck, total femur, and distal forearm. Complete cure is only possible through surgical resection of the adenoma(s). The indication for surgery is dependent on the age of the patient, existing complications, and the patient's preference. Diagnostic imaging should only be performed if surgery is planned. Typically, neck ultrasound and 99mTc MIBI scintigraphy are sufficient to localize the parathyroid adenoma. Presurgical diagnostic evaluation of the thyroid is reasonable for surgical planning. Vitamin-D deficiency should be normalized before surgery. Postsurgical calcium and vitamin-D administration will prevent postsurgical hypocalcemia and hungry-bone disease, and may optimize the outcome of BMD. Treatment of osteoporosis without fractures might not be necessary, owing to normalization of BMD several years after parathyroid surgery. The continuation of specific anti-osteoporotic treatment with bisphosphonates post-surgery did not have any advantage and hence cannot be recommended.

Serum Calcification Propensity and Calcification of the Abdominal Aorta in Patients With Primary Aldosteronism

Patients with primary aldosteronism (PA) are more susceptible to cardiovascular disease and mortality than patients with primary hypertension. This is mostly attributed to excess production of aldosterone and its effects on the development of vascular injury. A novel functional test (T₅₀) measures serum calcification propensity. Lower T₅₀-values predict higher cardiovascular risk. We investigated serum calcification propensity and vascular calcification in PA and resistant hypertension (RH). T₅₀ measurement was performed in patients with PA (n = 66) and RH (n = 28) at baseline and after 403 (279–640) and 389 (277–527) days of treatment. No significant differences in T₅₀-values were observed between the groups (371 ± 65 and 382 ± 44 min, in PA and RH group, respectively, p > 0.05). However, higher aldosterone-to-renin ratios were associated with lower T₅₀-values in PA-patients (r −0.282, p < 0.05). Furthermore, lower T₅₀-values were associated with increased abdominal aortic calcification measured by Agatston score in PA (r −0.534, p < 0.05). In both, PA and RH, higher atherosclerotic cardiovascular disease (ACSVD) scores (r −0.403, p < 0.05) and lower HDL (r 0.469, p < 0.05) was related to lower T₅₀-values in a linear regression model. Adrenalectomy or medical treatment did not increase T₅₀-values. In comparison to patients with stable T₅₀-values, PA patients with a decrease in T₅₀ after intervention had higher serum calcium concentrations at baseline (2.24 ± 0.11 vs. 2.37 ± 0.10 mmol/l, p < 0.05). This decline of T₅₀-values at follow-up was also associated with a decrease in serum magnesium (−0.03 ± 0.03 mmol/l, p < 0.05) and an increase in phosphate concentrations (0.11 ± 0.11 mmol/l, p < 0.05). Resistant hypertension patients with a decrease in T₅₀-values at follow-up had a significantly lower eGFR at baseline. In summary, these data demonstrate an association between a high aldosterone-to-renin ratio and low T₅₀-values in PA. Moreover, lower T₅₀-values are associated with higher ACSVD scores and more pronounced vascular calcification in PA. Thus, serum calcification propensity may be a novel modifiable risk factor in PA.

The Importance of Correlation between Aldosterone and Parathyroid Hormone in Patients with Primary Hyperparathyroidism

In primary hyperparathyroidism, an increased risk of developing the cardiovascular disease may exist due to increased activity of the renin-angiotensin-aldosterone system. The aim of this study was to evaluate the relationship between parathyroid hormone and aldosterone in patients with primary hyperparathyroidism. The study included 48 patients with primary hyperparathyroidism and 30 healthy subjects who matched age and gender to the study group. This study was conducted at the Center for Laboratory medicine, Clinical center of Vojvodina, Novi Sad, Serbia. In addition to clinical data and laboratory determination of the concentration of total and ionized calcium, phosphorus, measurements of parathyroid hormone, vitamin D, direct renin, and aldosterone were performed by the method of chemiluminescent technology. Compared to the controls, the study group had statistically significantly higher values of aldosterone (p=0.028), total calcium (p=0.01), ionized calcium (p=0.003) and parathyroid hormone (P ≤ 0.001) Serum aldosterone and parathyroid hormone levels were correlated positively in patients with primary hyperparathyroidism (r=0.509, p < 0.05). A statistically significant positive correlation between renin and parathyroid hormone (r=0.688, p < 0.05) and renin and calcium (r=0.673, p < 0.05) was determined in hyperparathyroid patients. In multivariate regression analysis, the strongest predictive variable of aldosterone secretion was parathyroid hormone (p=0.011). An independent relationship between parathyroid hormone and aldosterone in patients with primary hyperparathyroidism and the correlation between renin and parathyroid hormone as well as with calcium indicate not only the direct but also the indirect associations between parathyroid hormone and aldosterone in primary hyperparathyroidism. These findings may represent another possible model of renin-angiotensin-aldosterone-induced organ damage.

Association between Vitamin D Deficiency and Levels of Renin and Angiotensin in Essential Hypertension

OBJECTIVE

The present study aims to investigate the relationship between vitamin D deficiency and renin-angiotensin-aldosterone levels in patients with essential hypertension.

METHODS

The present study observed two groups of patients from Urumqi, Xinjiang, China, from April 2017 to March 2018. There were two subject groups: the hypertension group (80 patients with essential hypertension selected by random cluster sampling) and the control group (76 healthy adults). The 25-hydroxyvitamin D (25(OH)D or vitamin D) levels were measured through electrolytes; fasting blood glucose, blood lipids, and other biochemical indicators were detected using immune chemiluminescence; and plasma renin activity and angiotensin II concentrations were detected with radio-immunity.

RESULTS

Comparison between the hypertension group and control group showed statistically significant differences in the systolic pressure and levels of 25(OH)D, renin, and triglycerides (P < 0.05). The correlation analysis showed that 25(OH)D was negatively correlated with renin (r = -0.185; P=0.021) and positively correlated with systolic pressure (r = -0.105; P=0.035). There were no statistically significant differences in diastolic pressure, fasting blood glucose, total cholesterol, low-density lipoprotein cholesterol, high-density lipoprotein cholesterol, and triglycerides between the two groups.

CONCLUSIONS

The results of the present study show that vitamin D deficiency is common in Urumqi, Xinjiang, China and vitamin D levels are negatively correlated with renin levels. Vitamin D plays an important role in regulating blood pressure by affecting renin levels through the renin-angiotensin-aldosterone system.

The Association Between Dietary Inflammatory Index and Parathyroid Hormone in Adults With/Without Chronic Kidney Disease

Aims: We aimed to assess the association between dietary inflammation index (DII) with parathyroid hormone (PTH) and hyperparathyroidism (HP) in adults with/without chronic kidney disease (CKD).

Methods: Data were obtained from the 2003–2006 National Health and Nutrition Examination Survey (NHANES). The participants who were <18 years old, pregnant, or missing the data of DII, PTH, and CKD were excluded. DII was calculated based on a 24-h dietary recall interview for each participant. Weighted multivariable regression analysis and subgroup analysis were conducted to estimate the independent relationship between DII with PTH and the HP in the population with CKD/non-CKD.

Results: A total of 7,679 participants were included with the median DII of −0.24 (−2.20 to 1.80) and a mean PTH level of 43.42 ± 23.21 pg/ml. The average PTH was 45.53 ± 26.63 pg/ml for the participants in the highest tertile group compared with 41.42 ± 19.74 pg/ml in the lowest tertile group (P < 0.0001). The rate of HP was 11.15% overall, while the rate in the highest DII tertile was 13.28 and 8.60% in the lowest DII tertile (P < 0.0001). The participants with CKD tended to have higher PTH levels compared with their counterparts (61.23 ± 45.62 vs. 41.80 ± 19.16 pg/ml, P < 0.0001). A positive association between DII scores and PTH was observed (β = 0.46, 95% CI: 0.25, 0.66, P ≤ 0.0001), and higher DII was associated with an increased risk of HP (OR = 1.05, 95% CI: 1.02, 1.08, P = 0.0023). The results from subgroup analysis indicated that this association was similar in the participants with different renal function, gender, age, BMI, hypertension, and diabetes statuses and could also be appropriate for the population with CKD.

Conclusions: Higher consumption of a pro-inflammatory diet appeared to cause a higher PTH level and an increased risk of HP. Anti-inflammatory dietary management may be beneficial to reduce the risk of HP both in the population with and without CKD.

Aldosterone Secretion in Patients With Primary Hyperparathyroidism Without Arterial Hypertension

OBJECTIVE

There is a direct bidirectional link between parathyroid hormone (PTH) and the renin-angiotensin-aldosterone system (RAAS), but few studies evaluated the RAAS in patients with primary hyperparathyroidism (PHPT), mainly biased from concomitant antihypertensive treatment.

METHODS

We retrospectively evaluated a consecutive series of 130 normotensive patients with PHPT comparing aldosterone (ALD) levels and plasma renin activity (PRA) with the demographic, biochemical, or clinical features of PHPT.

RESULTS

No correlation was found between ALD and PRA, and the demographic, biochemical, and bone densitometry parameters in patients with PHPT without hypertension, with the exception of a negative correlation between age and serum PRA. Moreover, there was no significant correlation between PTH and ALD levels even in patients whose PTH level was >100 ng/L (P = .088).

CONCLUSION

In our normotensive patients with PHPT, the ALD, PRA, and aldosterone/renin ratio were not correlated to PTH and calcium levels. In addition, they were neither related to PHPT clinical presentation nor renal function, vitamin D status, bone mass loss, or the presence of comorbidities such as diabetes and obesity. Further studies are needed to clarify the complex interplay between PTH and the RAAS in the modern PHPT presentation.