25羟维生素D及甲状旁腺激素与高血压的关系

目的目前血清25羟维生素D[25-(OH)D]、甲状旁腺激素(PTH)与高血压是否直接相关尚无定论,文章旨在探讨三者之间的关系。方法选取2014年3月至2015年7月就诊于盛京医院心血管内科的患者368例,其中男性202例。按照是否患高血压分为高血压组(198例)和非高血压组(170例)。收集研究对象一般资料并检测PTH以及25-(OH)D水平。分析25-(OH)D、PTH与高血压之间的关系。结果高血压组患者25-(OH)D水平低于非高血压组(37.67±18.23 nmol/L比42.45±20.41 nmol/L,P=0.018)。两组间PTH水平差异无统计学意义(50.08±28.80 ng/L比50.45±22.37 ng/L,P=0.892)。Pearson相关性分析显示,25-(OH)D与PTH呈负相关(r=-0.225,P0.05)。二元Logistic回归分析显示维生素D缺乏或不足是高血压的独立危险因素(OR=1.847,95%CI 1.138~2.996,P=0.013),PTH升高与高血压发病风险不存在相关。结论维生素D不足或缺乏与高血压相关,是高血压的危险因素。     

低钙透析液对血甲状旁腺素及钙磷代谢的影响

目的:研究应用钙离子 1 .25mmol/L透析液进行透析 3个月对患者iPTH及钙磷水平的影响。　方法:维持性血液透析患者 6例,试验前用钙离子 1. 5mmol/L透析液每周透析 3次,每次透析 4h,均使用F6透析器(聚砜膜,面积 1 3m2 )。使用钙离子 1 25mmol/L透析液透析 3.个月,此期患者饮食中钙磷的摄入量稳定,用药不变。使用钙离子 1 25mmol/L透析液之前检测透析前血iPTH,透析前后血钙和血磷浓度。3个月后复查透析前血iPTH,透析前后血钙和血磷浓度,并检测使用钙离子 1. 25mmol/L透析液单次透析前、透析后及下一次透析前的血iPTH和血钙、血磷浓度。　结果:单次透析使用钙离子浓度 1 25mmol/L的透析液透析 4h,透后血钙浓度下降,透后血iPTH[ (219 .2±143. 3)ng/L]较透前[ (157. 5±107 .1)ng/L]明显升高 (P<0. 05),至下次透析前血钙浓度及血iPTH(157. 7±125 .3ng/L)基本恢复至上次透析前水平。使用钙离子 1 25mmol/L透析液透析 3个月后,iPTH水平较未使用时明显上升[ (157. 5±107 .1)ng/Lvs(82. 5±43 .7)ng/L,P<0 .05]。　结论:单次应用钙离子 1 .25mmol/L透析液进行透析, 透后血iPTH升高,但是至下一次透前血iPTH基本恢复至上次透前水平。长期应用 ( 3个月)钙离子 1 25mmol/L透析液进行透析,钙负荷减轻,血iPTH水平升     

Glomerular filtration rate and parathyroid hormone are associated with 1,25-dihydroxyvitamin D in men without chronic kidney disease

Abstract. Karhapää P, Pihlajamäki J, Pörsti I, Kastarinen M, Mustonen J, Niemelä O, Tuomi H, Kuusisto J (University of Eastern Finland, Kuopio; University of Tampere, Tampere; Finnish Medical Agency, Kuopio; and University of Tampere, Tampere, Finland). Glomerular filtration rate and parathyroid hormone are associated with 1,25‐dihydroxyvitamin D in men without chronic kidney disease. J Intern Med 2012; 271 : 573–580. Background and aim. Vitamin D, estimated glomerular filtration rate (eGFR) and parathyroid hormone (PTH) are related to cardiovascular disease risk. We examined the associations between the levels of 25‐hydroxyvitamin D (25‐D) and 1,25‐dihydroxyvitamin D (1,25‐D) and both eGFR and PTH. Design and setting. Cross‐sectional population‐based study in Kuopio, Eastern Finland. Subjects. A total of 909 men without known chronic kidney disease (CKD) and not receiving antidiabetic medication, aged from 45 to 73 years, were included in the study. Main outcome measures. Fasting levels of 25‐D, 1,25‐D, creatinine and PTH were measured, and an oral glucose tolerance test (OGTT) was performed. Results. High levels of 25‐D were associated with low levels of eGFR and PTH (β = ?0.17, P = 9 × 10^?7 and β = ?0.28, P = 6 × 10^?17, respectively, adjusted for age, body mass index and levels of calcium, phosphorus and glucose in a 2‐h OGTT, and also for either eGFR or PTH). By contrast, high 1,25‐D levels were associated with high levels of eGFR and PTH (β = 0.17, P = 2 × 10^?6 and β = 0.19, P = 5 × 10^?8, respectively, adjusted as mentioned earlier and additionally for 25‐D). Eighteen per cent of men in the highest 25‐D quartile were in the lowest 1,25‐D quartile and also had a lower eGFR than men with high levels of both 25‐D and 1,25‐D (P = 4 × 10^?5). Finally, 15% of men in the lowest 25‐D quartile were in the highest 1,25‐D quartile and also had higher PTH levels than men with low levels of both 25‐D and 1,25‐D (P = 2 × 10^?3). Conclusion. Our findings suggest that both eGFR and PTH are significantly associated with vitamin D metabolism in men without known CKD.     

Serum concentrations of vitamin D and parathyroid hormone and prevalent metabolic syndrome among adults in the United States

Background: Some reports suggest that concentrations of vitamin D are inversely, whereas concentrations of parathyroid hormone (PTH) are directly, associated with prevalent metabolic syndrome. Because of lingering uncertainty about these associations, we examined the cross‐sectional associations between serum concentrations of 25‐hydroxyvitamin D₃ and PTH with metabolic syndrome in a representative sample of adults in the US. Methods: We used data from 1705 participants in the 2005–2006 National Health and Nutrition Examination Survey. Vitamin D was measured by radioimmunoassay, whereas PTH was measured using an electrochemiluminescent process. Results: The mean concentration of vitamin D for participants with and without metabolic syndrome was 20.3 and 22.9 ng/mL, respectively (P = 0.001). The mean concentration of PTH for participants with and without metabolic syndrome was 44.5 and 41.0 pg/mL, respectively (P = 0.002). The age‐adjusted mean concentrations of vitamin D (P for linear trend <0.001) decreased linearly, whereas PTH (P for linear trend = 0.002) increased linearly, as the number of components of metabolic syndrome increased. After adjusting for age, gender, physical activity, urinary albumin creatinine ratio, and concentrations of C‐reactive protein and calcium, concentrations in the highest quintile of vitamin D [prevalence ratio (PR) = 0.59; 95% confidence interval (CI) 0.44–0.79], but not PTH (PR = 1.18; 95% CI 0.97–1.43), was significantly associated with prevalent metabolic syndrome. Conclusion: Concentrations of vitamin D, but not PTH, were significantly associated with prevalent metabolic syndrome among US adults.     

Variation in public‐funded bariatric surgery intervention rate by New Zealand region

Inequitable access to bariatric surgery by geographical region has been reported internationally, but comparable data on provision of bariatric surgery have not previously been reported in New Zealand. We examined allocated funding and provision of bariatric surgery amongst different regions in New Zealand in the 2013/14 year, and found that there was large variation in both. This highlights that public funded bariatric surgery needs to take into account population prevalence of morbid obesity to reduce inequities by geographical region.     

Vitamin D, parathyroid hormone, and bone mineral content of lumbar spine and femur in primary biliary cirrhosis

In order to elucidate the pathogenesis and degree of osteopoenia in primary biliary cirrhosis (PBC) we conducted a cross-sectional study of 47 non-selected female patients with biopsy-proven PBC. Bone mineral content (BMC) of the lumbar spine, femoral neck and femoral shaft was determined using dual photon absorptiometry. Compared to healthy females of corresponding decades the PBC patients exhibited significantly decreased mean BMC-values in lumbar spine (88%, P less than 0.05) and femoral neck (92%, P less than 0.05) but not in femoral shaft (96%, NS). Bone mineral content was not significantly associated with duration of liver disease, impairment of liver function (serum concentrations of albumin, clotting factors II + VII + X, bilirubin, alkaline phosphatase galactose elimination capacity or histology), variables reflecting calcium homeostasis (serum concentrations of ionized calcium, parathyroid hormone, vitamin D binding protein, 25-hydroxy vitamin D3 and 1,25-dihydroxy vitamin D3) or previous treatment with glucocorticosteroids. In view of our negative findings we suggest that future studies in this field should focus on physical activity and female sex hormones as determinants for the prevention of osteopoenia in females with primary biliary cirrhosis.     

High parathyroid hormone,but not low vitamin D concentrations,expose elderly inpatients to hypertension

Aim: Serum parathyroid hormone (PTH) and 25‐hydroxyvitamin D (25OHD) concentrations might contribute to blood pressure (BP) levels. Mixed results in previous literature could be due to the failure to consider both these hormones concurrently, despite their long‐known relationship. Our objective was to examine the association of serum intact PTH and 25OHD concentrations with BP levels amongst older inpatients, while accounting for each other. Methods: The participants were 284 Caucasian older inpatients with no suspicion of primary hyperparathyroidism (mean age 85.87 ± 5.90 years; 65.8% female) admitted to the geriatric acute care unit of Angers University Hospital, France. They were divided into two groups according to the existence of hypertension (i.e. systolic blood pressure [SBP] >140 mmHg, or diastolic blood pressure [DBP] >90 mmHg). Age, sex, numbers of chronic diseases and of drugs taken daily, use of antihypertensive or corticosteroid drugs and of calcium supplements/vitamin D, thyroid‐stimulating hormone and albumin concentrations, creatinine clearance, and season tested were used as covariables. Results: Hypertensive participants (n = 106) had higher intact PTH concentrations than normotensive patients (P = 0.044). There was a positive linear association of BP with intact PTH concentrations (adjusted β = 0.08, P = 0.015 for SBP; adjusted β = 0.05, P = 0.044 for DBP), but not with vitamin D. Serum intact PTH concentration, unlike 25OHD, was associated with hypertension (adjusted OR 1.01, P = 0.038). Conclusions: Irrespective of 25OHD, PTH was associated with hypertension by increasing both SBP and DBP. Geriatr Gerontol 2013; 13: 783–791 .     

Disorders of calcium homeostasis

To ensure a multitude of essential cellular functions, the extracellular concentration of calcium is maintained within a narrow physiological range. This depends on integrated regulation of calcium fluxes with respect to the intestine, kidneys and bone. The precise regulation of serum calcium is controlled by calcium itself, through a calcium receptor and several hormones, the most important of which are parathyroid hormone and 1,25(OH)(2) vitamin D. This balance can be disturbed by mutations in the calcium-sensing receptor, inappropriately high or low levels of parathyroid hormone, resistance to parathyroid hormone effects, insufficient intake or production of 1,25(OH)(2) vitamin D and inactivation of the vitamin D receptor. Mineral homeostasis is moreover influenced by many other systemic factors (e.g. sex steroid, thyroid and glucocorticoid hormones) or humoral factors (e.g. cytokines and growth factors). A specific example is the major abnormalities of mineral homeostasis in case of malignancy by excessive production of parathyroid hormone-related peptide resulting in hypercalcaemia. Several new drugs have been developed based on factors in this axis, including calcimimetics, calcilytics, vitamin D analogues and parathyroid hormone-related peptide inhibitors.     

2型糖尿病患者血清25-羟维生素D和甲状旁腺激素水平与高血压病的相关性

目的探讨2型糖尿病患者血清25-羟基维生素D[25-(OH)D]、甲状旁腺激素(PTH)水平与其发生高血压的相关性。方法回顾性分析128例2型糖尿病住院患者,按照其是否合并原发性高血压病分为合并高血压组(89例)、无高血压组(39例)。收集研究对象的一般资料及检测血清PTH、25-(OH)D水平。分析25-(OH)D、PTH与2型糖尿病是否罹患高血压之间的关系。结果合并高血压组患者血清25-(OH)D水平低于无高血压组(P0.001)。两组间PTH水平差异无统计学意义(P=0.132)。Pearson相关性分析显示,25-(OH)D与PTH呈负相关(r=-0.182,P0.05)。二元Logistic回归分析显示25-(OH)D降低是2型糖尿病伴发高血压的危险因素(OR=0.935,95%CI 0.883～0.991,P=0.023),而PTH升高不是糖尿病患者易患高血压的危险因素。结论糖尿病患者易合并25-(OH)D降低,且25-(OH)D降低是糖尿病患者罹患高血压病的危险因素。     

Diagnostic applicability of intact and midregion/C-terminal parathyroid hormone assays in calcium metabolic disorders

We compared measurements of parathyroid hormone (PTH) using two assays, in order to detect intact PTH and midregion/C-terminal PTH (M/C-PTH) in a variety of calcium metabolic disorders. The series consisted of a total of 101 patients, including subjects with primary hyperparathyroidism (n = 24), hypoparathyroidism (n = 18), hypercalcaemia of malignancy (n = 10), moderate chronic renal failure (n = 14), chronic renal failure undergoing haemodialysis (n = 19), and small bowel disorders (n = 16). The intact PTH assay was superior to the M/C-PTH assay in reflecting parathyroid function in primary hyperparathyroidism, hypoparathyroidism and hypercalcaemia of malignancy. In patients with chronic renal failure, both assays were indicators of a comparable number of patients with elevated PTH levels. Intact PTH proved most reliable in detecting changes in parathyroid hormone secretion in response to variations in ionized calcium induced by haemodialysis. In patients with extensive intestinal resection, both assays showed increased levels of PTH. It is concluded that measurement of intact PTH is a more reliable index of parathyroid function than measurement of midregion/C-terminal PTH. Thus such an approach should be the one of choice for clinical evaluation of calcium homeostasis.