Vascular uptake on 18F-sodium fluoride positron emission tomography:precursor of vascular calcification?

Background: Microcalcifications cannot be identified with the present resolution of CT; however, 18F-sodium fluoride (18F-NaF) positron emission tomography (PET) imaging has been proposed for non-invasive identification of microcalcification. The primary objective of this study was to assess whether 18F-NaF activity can assess the presence and predict the progression of CT detectable vascular calcification. Methods and Results: The data of two longitudinal studies in which patients received a 18F-NaF PET-CT at baseline and after 6 months or 1-year follow-up were used. The target to background ratio (TBR) was measured on PET at baseline and CT calcification was quantified in the femoral arteries at baseline and follow-up. 128 patients were included. A higher TBR at baseline was associated with higher calcification mass at baseline and calcification progression (β = 1.006 [1.005-1.007] and β = 1.002 [1.002-1.003] in the studies with 6 months and 1-year follow-up, respectively). In areas without calcification at baseline and where calcification developed at follow-up, the TBR was.11–.13 (P < .001) higher compared to areas where no calcification developed. Conclusion: The activity of 18F-NaF is related to the amount of calcification and calcification progression. In areas where calcification formation occurred, the TBR was slightly but significantly higher

Genotype-phenotype correlation in pseudoxanthoma elasticum

Background and aims: Pseudoxanthoma elasticum (PXE) is caused by variants in the ABCC6 gene. It results in calcification in the skin, peripheral arteries and the eyes, but has considerable phenotypic variability. We investigated the association between the ABCC6 genotype and calcification and clinical phenotypes in these different organs. Methods: ABCC6 sequencing was performed in 289 PXE patients. Genotypes were grouped as two truncating, mixed, or two non-truncating variants. Arterial calcification mass was quantified on whole body, low dose CT scans; and peripheral arterial disease was measured with the ankle brachial index after treadmill test. The presence of pseudoxanthoma in the skin was systematically scored. Ophthalmological phenotypes were the length of angioid streaks as a measure of Bruchs membrane calcification, the presence of choroidal neovascularizations, severity of macular atrophy and visual acuity. Regression models were built to test the age and sex adjusted genotype-phenotype association. Results: 158 patients (median age 51 years) had two truncating variants, 96 (median age 54 years) a mixed genotype, 18 (median age 47 years) had two non-truncating variants. The mixed genotype was associated with lower peripheral (13: 0.39, 95%CI:-0.62;-0.17) and total (13: 0.28, 95%CI:-0.47;-0.10) arterial calcification mass scores, and lower prevalence of choroidal neovascularizations (OR: 0.41 95%CI:0.20; 0.83) compared to two truncating variants. No association with pseudoxanthomas was found. Conclusions: PXE patients with a mixed genotype have less severe arterial and ophthalmological phenotypes than patients with two truncating variants in the ABCC6 gene. Research into environmental and genetic modifiers might provide further insights into the unexplained phenotypic variability

Increased Elastin Degradation in Pseudoxanthoma Elasticum Is Associated with Peripheral Arterial Disease Independent of Calcification

Pseudoxanthoma elasticum (PXE) results in extensive fragmentation and calcification of elastin fibers in the peripheral arteries, which results in peripheral arterial disease (PAD). Current research focuses on the role of calcifications in the pathogenesis of PXE. Elastin degradation and calcification are shown to interact and may amplify each other. This study aims to compare plasma desmosines, a measure of elastin degradation, between PXE patients and controls and to investigate the association between desmosines and (1) arterial calcification, (2) PAD, and (3) PAD independent of arterial calcification in PXE. Plasma desmosines were quantified with liquid chromatography-tandem mass spectrometry in 93 PXE patients and 72 controls. In PXE patients, arterial calcification mass was quantified on CT scans. The ankle brachial index (ABI) after treadmill test was used to analyze PAD, defined as ABI &lt; 0.9, and the Fontaine classification was used to distinguish symptomatic and asymptomatic PAD. Regression models were built to test the association between desmosines and arterial calcification and arterial functioning in PXE. PXE patients had higher desmosines than controls (350 (290&ndash;410) ng/L vs. 320 (280&ndash;360) ng/L, p = 0.02). After adjustment for age, sex, body mass index, smoking, type 2 diabetes mellitus, and pulmonary abnormalities, desmosines were associated with worse ABI (&beta; (95%CI): &minus;68 (&minus;132; &minus;3) ng/L), more PAD (&beta; (95%CI): 40 (7; 73) ng/L), and higher Fontaine classification (&beta; (95%CI): 30 (6; 53) ng/L), but not with arterial calcification mass. Lower ABI was associated with higher desmosines, independent from arterial calcification mass (&beta; (95%CI): &minus;0.71(&minus;1.39; &minus;0.01)). Elastin degradation is accelerated in PXE patients compared to controls. The association between desmosines and ABI emphasizes the role of elastin degradation in PAD in PXE. Our results suggest that both elastin degradation and arterial calcification independently contribute to PAD in PXE

Determinants of 18F-NaF uptake in femoral arteries in patients with type 2 diabetes mellitus

Background: The goal of this study was to investigate the potential determinants of 18F-NaF uptake in femoral arteries as a marker of arterial calcification in patients with type 2 diabetes and a history of arterial disease. Methods and Results: The study consisted of participants of a randomized controlled trial to investigate the effect of vitamin K2 (NCT02839044). In this prespecified analysis, subjects with type 2 diabetes and known arterial disease underwent full body 18F-NaF PET/CT. Target-to-background ratio (TBR) was calculated by dividing the mean SUVmax from both superficial femoral arteries by the SUVmean in the superior vena cava (SVC) and calcium mass was measured on CT. The association between 18F-NaF TBR and cardiovascular risk factors was investigated using uni- and multivariate linear regression corrected for age and sex. In total, 68 patients (mean age: 69 ± 8 years; male: 52) underwent 18F-NaF PET/CT. Higher CT calcium mass, total cholesterol, and HbA1c were associated with higher 18F-NaF TBR after adjusting. Conclusion: This study shows that several modifiable cardiovascular risk factors (total cholesterol, triglycerides, HbA1c) are associated with femoral 18F-NaF tracer uptake in patients with type 2 diabetes

Bisphosphonates for cardiovascular risk reduction : A systematic review and meta-analysis

BACKGROUND AND AIMS: Bisphosphonates might be effective in reducing cardiovascular events due to their ability to reduce calcification in arterial walls. We aimed to investigate the effects of treatment with bisphosphonates on the prevention of atherosclerotic processes and cardiovascular disease. METHODS: Pubmed, Embase and the Cochrane Library were systematically reviewed by two independent investigators for randomized controlled studies published up to January 2016, in which the effect of bisphosphonates on arterial wall disease, cardiovascular events, cardiovascular mortality or all-cause mortality were reported. There was no restriction for the type of population used in the trials. Random-effects models were used to calculate the pooled estimates. RESULTS: 61 trials reporting the effects of bisphosphonates on the outcomes of interest were included. Bisphosphonates had beneficial effects on arterial wall disease regarding arterial calcification (pooled mean percentage difference of 2 trials -11.52 (95% CI -16.51 to -6.52, p < 0.01, I(2) 13%), but not on arterial stiffness (pooled mean percentage difference of 2 trials -2.82; 95% CI -10.71-5.07; p = 0.48, I(2) 59%). No effect of bisphosphonate treatment on cardiovascular events was found (pooled RR of 20 trials 1.03; 95% CI 0.91-1.17, I(2) 16%), while a lower risk for cardiovascular mortality was observed in patients treated with bisphosphonates (pooled RR of 10 trials 0.81; 95% CI 0.64-1.02; I(2) 0%) although not statistically significant. Patients treated with bisphosphonates had a reduced risk of all-cause mortality (pooled RR of 48 trials 0.90; 95% CI 0.84-0.98; I(2) 53%). CONCLUSIONS: In this systematic review and meta-analysis it is shown that bisphosphonates reduce arterial wall calcification but have no effect on arterial stiffness or on cardiovascular events. Bisphosphonates tend to reduce the risk of cardiovascular mortality and reduce all-cause mortality in various patient groups, including osteoporosis and cancer patients

Six months vitamin K treatment does not affect systemic arterial calcification or bone mineral density in diabetes mellitus 2

Purpose: Vitamin K-dependent proteins are involved in (patho)physiological calcification of the vasculature and the bones. Type 2 diabetes mellitus (DM2) is associated with increased arterial calcification and increased fractures. This study investigates the effect of 6 months vitamin K2 supplementation on systemic arterial calcification and bone mineral density (BMD) in DM2 patients with a history of cardiovascular disease (CVD). Methods: In this pre-specified, post hoc analysis of a double-blind, randomized, controlled clinical trial, patients with DM2 and CVD were randomized to a daily, oral dose of 360 µg vitamin K2 or placebo for 6 months. CT scans were made at baseline and follow-up. Arterial calcification mass was quantified in several large arterial beds and a total arterial calcification mass score was calculated. BMD was assessed in all non-fractured thoracic and lumbar vertebrae. Results: 68 participants were randomized, 35 to vitamin K2 (33 completed follow-up) and 33 to placebo (27 completed follow-up). The vitamin K group had higher arterial calcification mass at baseline [median (IQR): 1694 (812–3584) vs 1182 (235–2445)] for the total arterial calcification mass). Six months vitamin K supplementation did not reduce arterial calcification progression (β [95% CI]: − 0.02 [− 0.10; 0.06] for the total arterial calcification mass) or slow BMD decline (β [95% CI]: − 2.06 [− 11.26; 7.30] Hounsfield units for all vertebrae) when compared to placebo. Conclusion: Six months vitamin K supplementation did not halt progression of arterial calcification or decline of BMD in patients with DM2 and CVD. Future clinical trials may want to pre-select patients with very low vitamin K status and longer follow-up time might be warranted. This trial was registered at clinicaltrials.gov as NCT0283904

Six months vitamin K treatment does not affect systemic arterial calcification or bone mineral density in diabetes mellitus 2

Purpose: Vitamin K-dependent proteins are involved in (patho)physiological calcification of the vasculature and the bones. Type 2 diabetes mellitus (DM2) is associated with increased arterial calcification and increased fractures. This study investigates the effect of 6 months vitamin K2 supplementation on systemic arterial calcification and bone mineral density (BMD) in DM2 patients with a history of cardiovascular disease (CVD). Methods: In this pre-specified, post hoc analysis of a double-blind, randomized, controlled clinical trial, patients with DM2 and CVD were randomized to a daily, oral dose of 360 µg vitamin K2 or placebo for 6 months. CT scans were made at baseline and follow-up. Arterial calcification mass was quantified in several large arterial beds and a total arterial calcification mass score was calculated. BMD was assessed in all non-fractured thoracic and lumbar vertebrae. Results: 68 participants were randomized, 35 to vitamin K2 (33 completed follow-up) and 33 to placebo (27 completed follow-up). The vitamin K group had higher arterial calcification mass at baseline [median (IQR): 1694 (812–3584) vs 1182 (235–2445)] for the total arterial calcification mass). Six months vitamin K supplementation did not reduce arterial calcification progression (β [95% CI]: − 0.02 [− 0.10; 0.06] for the total arterial calcification mass) or slow BMD decline (β [95% CI]: − 2.06 [− 11.26; 7.30] Hounsfield units for all vertebrae) when compared to placebo. Conclusion: Six months vitamin K supplementation did not halt progression of arterial calcification or decline of BMD in patients with DM2 and CVD. Future clinical trials may want to pre-select patients with very low vitamin K status and longer follow-up time might be warranted. This trial was registered at clinicaltrials.gov as NCT0283904