Low vitamin D concentration is not associated with increased mortality and morbidity after cardiac surgery

Elevated Serum Fibroblast Growth Factor 23 (FGF-23) Perseveres into a Convalescence Period After Elective Cardiac Surgery, with Receptor Activator of Nuclear Factor κB Ligand (RANKL) and Cartilage Oligomeric Matrix Protein (COMP) Being Part of the Peri-Surgical -Pro-Arteriosclerotic Inflammatory Response

BACKGROUND Receptor activator of nuclear factor kappa B ligand (RANKL), osteoprotegerin (OPG), cartilage oligomeric matrix protein (COMP), bone morphogenetic protein (BMP-2), and fibroblast growth factor 23 (FGF-23) are involved in inflammation, calcium deposition, and fibrosis of blood vessels. Acute changes in these factors may contribute to the progression of arteriosclerosis, especially if their elevated serum levels persist postoperatively. MATERIAL AND METHODS A total of 90 patients (79 White, 4 African American, and 7 Other) undergoing elective heart surgery were enrolled in the study. Blood was collected before surgery and after surgery at 24 hours, 7 days, and 3 months to allow for longitudinal comparisons. After the plasma isolation, several biomarkers levels were studied using an enzymatic-linked assay. Demographic and clinical information were obtained from electronic health records. RESULTS At 24 hours after surgery, RANKL (RANKLbaseline=248.7±215.7 vs RANKLt24h=376.4±329.7; P=0.035), and BMP-2 (BMP-2baseline=283.7±255.4 vs BMP-2t24h=482.4; P=0.015) were significantly elevated compared to baseline, with levels returning to baseline at 7 days. FGF-23 increased significantly from baseline (FGF-23baseline=1020±1210) to 7 days (FGF-237d=2191±5188; P=0.029) and remained significantly higher than baseline at 3 months (FGF-233m=2041±3521; P=0.044). White blood cells (WBC) remained elevated at discharge (WBCbaseline=6.8±2.1 vs WBC24h=15.0±5.3 vs WBCdischarge=8.8±3.4). IL-8 and C-reactive protein normalized at 3 months. Estimated blood loss was significantly correlated with RANKL at 24 hours (r²=0.33; P=0.035). Serum creatinine levels after surgery at 24 hours (r²=0.41; p=0.008) and 7 days (r²=0.59; P=0.000) was strongly correlated with COMP. CONCLUSIONS Persistent elevation of serum FGF-23 indicates a potential for accelerated arteriosclerosis after cardiac surgery.

Association Between the Circulating Level of 25-Hydroxyvitamin D and Clinical Results After Cardiac Surgery: A Meta-Analysis and Systematic Review

Background: Vitamin D (VitD) is an important pleiotropic hormone for organ systems. Studies have focused on the level of VitD, especially that of 25-hydroxyvitamin D (25-(OH)-VitD), in patients after cardiac surgery and the relationship between VitD deficiency and adverse outcomes, but the results have been inconsistent. We carried out a meta-analysis to evaluate differences in the 25-(OH)-VitD level before and after cardiac surgery, and evaluated the predictive value of 25-(OH)-VitD level in the clinical outcomes of patients undergoing cardiac surgery.

Methods: Studies related to VitD level and cardiac surgery were searched from PubMed, EMBASE, Web of Science, and Cochrane Central Register of Controlled Trials databases from inception to October 2020. We applied the Newcastle–Ottawa Scale to assess the risk of a bias in individual studies. We examined the heterogeneity and publication bias and performed subgroup analyses and sensitivity analyses.

Results: Fifteen studies were included in our analysis. The 25-(OH)-VitD level was significantly lower immediately after surgery [stand mean difference (SMD), 0.69; 95%CI (0.1, 1.28), P = 0.023] and 24-h after surgery [0.84; (0.47, 1.21), 0.000] compared with that before surgery. A higher prevalence of 25-(OH)-VitD deficiency was recorded 24 h after surgery [RR, 0.59; 95%CI (0.47, 0.73), P = 0.00]. Pooled results demonstrated a significant relationship between the preoperative 25-(OH)-VitD level and vasoactive-inotropic score (VIS) [SMD, −3.71; 95%CI (−6.32, −1.10); P = 0.005], and patients with 25-(OH)-VitD deficiency revealed a comparatively poor prognosis and severe condition after cardiac surgery [−0.80; (−1.41, −0.19), 0.01]. However, 25-(OH)-VitD deficiency was not associated with the duration of stay in the intensive care unit.

Conclusions: Cardiac surgery would leads to deficiency of 25-(OH)-VitD. And the preoperative and postoperative levels of 25-(OH)-VitD are associated with adverse events, which is eligible to work as an indicator to demonstrate clinical outcomes.

The promise and pitfalls of composite endpoints in sepsis and COVID-19 clinical trials

Composite endpoints reveal the tendency for statistical convention to arise locally within subfields. Composites are familiar in cardiovascular trials, yet almost unknown in sepsis. However, the VITAMINS trial in patients with septic shock adopted a composite of mortality and vasopressor-free days, and an ordinal scale describing patient status rapidly became standard in COVID studies. Aware that recent use could incite interest in such endpoints, we are motivated to flag their potential value and pitfalls for sepsis research and COVID studies.

Preoperative Vitamin D Concentration and Cardiac, Renal, and Infectious Morbidity after Noncardiac Surgery

BACKGROUND

Low 25-hydroxyvitamin D is associated with cardiovascular, renal, and infectious risks. Postsurgical patients are susceptible to similar complications, but whether vitamin D deficiency contributes to postoperative complications remains unclear. We tested whether low preoperative vitamin D is associated with cardiovascular events within 30 days after noncardiac surgery.

METHODS

We evaluated a subset of patients enrolled in the biobank substudy of the Vascular events In noncardiac Surgery patIents cOhort evaluatioN (VISION) study, who were at least 45 yr with at least an overnight hospitalization. Blood was collected preoperatively, and 25-hydroxyvitamin D was measured in stored samples. The primary outcome was the composite of cardiovascular events (death, myocardial injury, nonfatal cardiac arrest, stroke, congestive heart failure) within 30 postoperative days. Secondary outcomes were kidney injury and infectious complications.

RESULTS

A total of 3,851 participants were eligible for analysis. Preoperative 25-hydroxyvitamin D concentration was 70 ± 30 nmol/l, and 62% of patients were vitamin D deficient. Overall, 26 (0.7%) patients died, 41 (1.1%) had congestive heart failure or nonfatal cardiac arrest, 540 (14%) had myocardial injury, and 15 (0.4%) had strokes. Preoperative vitamin D concentration was not associated with the primary outcome (average relative effect odds ratio [95% CI]: 0.93 [0.85, 1.01] per 10 nmol/l increase in preoperative vitamin D, P = 0.095). However, it was associated with postoperative infection (average relative effect odds ratio [95% CI]: 0.94 [0.90, 0.98] per 10 nmol/l increase in preoperative vitamin D, P adjusted value = 0.005) and kidney function (estimated mean change in postoperative estimated glomerular filtration rate [95% CI]: 0.29 [0.11, 0.48] ml min 1.73 m per 10 nmol/l increase in preoperative vitamin D, P adjusted value = 0.004).

CONCLUSIONS

Preoperative vitamin D was not associated with a composite of postoperative 30-day cardiac outcomes. However, there was a significant association between vitamin D deficiency and a composite of infectious complications and decreased kidney function. While renal effects were not clinically meaningful, the effect of vitamin D supplementation on infectious complications requires further study.

Calcitriol trend following pediatric cardiac surgery and association with clinical outcome

BACKGROUND

Consistent with accepted practice in stable ambulatory populations, the majority of ICU research has evaluated vitamin D status using a single blood 25-hydroxyvitamin D (25(OH)D) level. Only a limited number of ICU studies have measured the active hormone, 1,25-dihydroxyvitamin D (calcitriol) and none have used change in calcitriol levels to evaluate axis functioning. The objective of this study was to describe the impact of Congenital Heart Disease (CHD) surgery on calcitriol levels and evaluate the relationship between change in postoperative levels and clinical course.

METHODS

Secondary analysis of a prospective cohort study of 56 children undergoing surgery for CHD.

RESULTS

Mean calcitriol levels dropped from 122.3 ± 69.1 pmol/L preoperatively to 65.3 ± 36.5 pmol/L (p < 0.0001) at PICU admission. The majority (61%, n = 34) were unable to increase calcitriol levels in the 48 h immediately following surgery. Post operative trend in calcitriol was inversely related to cardiovascular dysfunction, fluid requirements, ventilatory support and PICU length of stay (p < 0.01).

CONCLUSION

CHD patients had significant dysfunction of the vitamin D axis immediately postoperatively, demonstrated by both a significant intraoperative decline in calcitriol and inability to increase levels. Interventional research will be required to determine whether the use of calcitriol, in addition to cholecalciferol, reduces postoperative illness severity.

Current Evidence about Nutrition Support in Cardiac Surgery Patients-What Do We Know?

Nutrition support is increasingly recognized as a clinically relevant aspect of the intensive care treatment of cardiac surgery patients. However, evidence from adequate large-scale studies evaluating its clinical significance for patients&rsquo; mid- to long-term outcome remains sparse. Considering nutrition support as a key component in the perioperative treatment of these critically ill patients led us to review and discuss our understanding of the metabolic response to the inflammatory burst induced by cardiac surgery. In addition, we discuss how to identify patients who may benefit from nutrition therapy, when to start nutritional interventions, present evidence about the use of enteral and parenteral nutrition and the potential role of pharmaconutrition in cardiac surgery patients. Although the clinical setting of cardiac surgery provides advantages due to its scheduled insult and predictable inflammatory response, researchers and clinicians face lack of evidence and several limitations in the clinical routine, which are critically considered and discussed in this paper.

Serum Total 25-OH Vitamin D Adds Little Prognostic Value in Patients Undergoing Coronary Catheterization

BACKGROUND

Vitamin D deficiency is associated with an increased risk of cardiovascular disease; however, it is unclear whether vitamin D status should be considered in clinical risk assessments of patients with cardiovascular disease.

METHODS AND RESULTS

This study included 2975 patients who had their first serum total 25-hydroxy vitamin D (25-OH vitamin D) measurement before their first coronary catheterization in Alberta, Canada. Cox regression was used to examine associations between 25-OH vitamin D and mortality risk after adjusting for demographic and clinical risk factors. Interactions were tested using multiplicative terms, and prognostic value was assessed using measures of model discrimination, fit, calibration and net reclassification improvement. There were 401 deaths over a median of 5.8 years of follow-up. Serum total 25-OH vitamin D was inversely associated with mortality after adjusting for demographic and clinical risk factors, which was largely driven by excess risk in the bottom quintile (hazard ratio 1.84 for bottom versus top quintile, 95% CI 1.36-2.50, P for trend <0.001). Associations were weaker in the presence of several competing risk factors (e.g., advanced age; P for interactions <0.05). Adding 25-OH vitamin D to a model containing demographic and clinical risk factors yielded similar discrimination, model fit, and calibration and only modest improvements in risk reclassification (net reclassification improvement 1.9% for deaths, 2.3% for survivors).

CONCLUSIONS

Pre-catheterization, serum total 25-OH vitamin D was inversely associated with mortality risk after adjusting for established demographic and clinical risk factors. This association was attenuated by several competing risk factors. Overall, 25-OH vitamin D added little prognostic value over established risk factors; therefore, its measurement is not warranted in patients undergoing coronary catheterization.

Circulating 25-Hydroxyvitamin D and 1,25-Dihydroxyvitamin D Concentrations and Postoperative Infections in Cardiac Surgical Patients: The CALCITOP-Study

BACKGROUND

Vitamin D has immunomodulatory properties and seems to reduce the risk of infections. Whether low vitamin D concentrations are independent risk factors for nosocomial postoperative infections in surgical patients remains to be studied in detail.

METHODS

In 3,340 consecutive cardiac surgical patients, we investigated the association of circulating 25-hydroxyvitamin D (25OHD; indicator of nutritional vitamin D status) and 1,25-dihydroxyvitamin D (1,25[OH]2D; active vitamin D hormone) with nosocomicial infections. The primary endpoint was a composite of thoracic wound infection, sepsis, and broncho-pulmonary infection. Vitamin D status was measured on the last preoperative day. Infections were assessed until discharge. Logistic regression analysis was used to examine the association between vitamin D metabolite concentrations and the composite endpoint.

RESULTS

The primary endpoint was reached by 5.6% (n = 186). In patients who reached and did not reach the endpoint, in-hospital mortality was 13.4% and 1.5%, respectively (P<0.001). Median (IQR) 25OHD and 1,25(OH)2D concentrations were 43. 2 (29.7-61.9) nmol/l and 58.0 (38.5-77.5) pmol/l, respectively. Compared with the highest 1,25(OH)2D quintile (>81.0 pmol/l), the multivariable-adjusted odds ratio of infection was 2.57 (95%CI:1.47-4.49) for the lowest 1,25(OH)2D quintile (<31.5 pmol/l) and 1.85 (95%CI:1.05-3.25) for the second lowest quintile (31.5-49.0 pmol/l). There was no significant association between 25OHD concentrations and the primary endpoint.

CONCLUSIONS

Our data indicate an independent association of low 1,25(OH)2D levels with the risk of postoperative infections in cardiac surgical patients. Future studies should pay more attention on the clinical relevance of circulating 1,25(OH)2D and its regulation.

Vitamin D and Anaesthesia

Vitamin D is a vitamin not only associated with calcium-phosphorus metabolism but also affects many organ systems. Because of its effect on the immune system in recent years, it has attracted much attention. Vitamin D deficiency is a clinical condition that can be widely observed in the society. Thus, patients with vitamin D deficiency are often seen in anaesthesia practice. In the absence of vitamin D, prolongation of intensive care unit stay, increase in mortality and morbidity and also association of chronic diseases further increase the importance of vitamin D deficiency. The results obtained from studies have led to the question of whether poor surgical outcome is associated with vitamin D deficiency. We assessed the vitamin D deficiency and its negative consequences for the anaesthesiologist.

Vitamin D status and surgical outcomes: a systematic review

The importance of vitamin D for musculoskeletal health has long been recognized, and awareness of significant extra-skeletal effects in health and disease is rapidly emerging. Although it has been possible for many decades to quantify serum markers of vitamin D deficiency, and to correct deficiency at low cost and with high safety, the influence of vitamin D status on post-surgical outcomes has only recently been identified as a research topic of interest. To the present, these data have not been the subject matter of formal review. Accordingly, we conducted a systematic review to assess the association between perioperative vitamin D status and outcomes after surgery. The databases of PubMed, Ovid MEDLINE, EMBASE, AMED, CINAHL (EBSCOHost), The Cochrane Databases of Systematic Review, and PROSPERO were searched through December, 2014 for studies relating to vitamin D and surgery. The initial search yielded 90 manuscripts. After applying exclusion criteria, 31 studies were eligible for inclusion. Fifteen studies employed prospective observational designs, 3 used prospective randomized protocols, and 13 report retrospective database interrogations. The main finding of the present review is that 26 of 31 studies (84%) report at least one statistically significant worse outcome in patients with low vitamin D status. Five of 31 studies (16%) found no association. In conclusion, this review supports the hypothesis that hypovitaminosis D is associated with adverse outcomes after diverse surgical procedures. Future studies should focus on additional surgeries and outcomes, and on the role of vitamin D supplementation in the improvement of patient safety in participants with low vitamin D status at the time of surgery.

The relationship between immediate preoperative serum 25-hydroxy-vitamin D₃ levels and cardiac function, dysglycemia, length of stay, and 30-d readmissions in cardiac surgery patients

OBJECTIVES

Vitamin D has pleiotropic effects on cardiac, renal, and endocrine diseases like diabetes mellitus and deficiency has been correlated with increased Intensive Care Unit (ICU) morbidity and mortality. We studied the relationship between preoperative Vitamin D levels and several short-term endpoints including cardiovascular events, glucose levels, ICU, and hospital length of stay.

METHODS

Standard demographic data were obtained. Blood samples were drawn for 25-hydroxy-vitamin D3 (Vit D) levels at baseline (just before induction of anesthesia) and on postoperative day (POD #1). The number of inotropes used on POD # 0, 1, and 2 was recorded as well as the Cardiac Index (CI). Baseline glucose, Blood Urea Nitrogen and Creatinine (Cr) levels were obtained and repeated on POD # 1 & 2. Other variables studied are number of days of ICU and hospital stay.

RESULTS

Of the 64 patients included in the cohort, 3 were excluded because of inadequate data. 69% had Vit D levels <20 ng/mL and 31% had levels ≥20 ng/mL. More than 90% of the cohort had a significant decrease in POD # 1 Vit D levels (P < 0.001). Age, sex, race, and body mass index did not predict the preoperative Vit D levels; however, the timing of surgery was associated with preoperative Vit D levels, lowest in subjects who had surgery performed during winter. Preoperative Vit D levels had no effect on postoperative glycemic control, cardiac index, or composite outcome-arrhythmias, respiratory failure, or prolonged inotropic support. On regression analysis, preoperative Vit D levels did show a significant effect on ICU and hospital length of stay in this cohort.

CONCLUSIONS

The low levels in this study truly represent the Vit D status as they were obtained before any intervention, including surgery or fluid administration. Vit D levels decreased rapidly after surgery and hence future studies on Vit D may need to focus on premorbid levels obtained at the time of initial presentation and not those obtained after resuscitation or ICU admission. In contrast to epidemiologic reports, we found no association between low Vit D levels and postoperative cardiovascular events. However, low Vit D levels did affect the ICU and hospital length of stay in patients who were undergoing cardiac surgery. This is an important finding especially when many institutions and regulatory agencies are investigating novel therapies and processes to reduce the length of hospitalization. More studies are required to investigate the effect on hospital length of stay of early preadmission or preoperative Vit D supplementation before elective surgery.

Vitamin D deficiency in surgical congenital heart disease: prevalence and relevance

Vitamin D is a pleiotropic hormone important for the proper functioning of multiple organ systems. An emerging body of adult and pediatric critical care literature strongly suggests that vitamin D deficiency contributes to secondary organ pathophysiology, prolongs ICU stay, and worsens outcome in critically ill populations. Recent clinical studies suggest that a significant number of children with congenital heart disease (CHD) have post-operative vitamin D deficiency which appears to be associated with greater cardiovascular dysfunction. Altogether the cumulative body of literature suggests that peri-operative optimization of vitamin D status has the potential to speed recovery and/or improve outcome. This review describes the epidemiological and basic science research linking vitamin D deficiency to post-operative organ dysfunction. Furthermore, the available supplementation approaches are reviewed in the context of prevention of post-operative vitamin D deficiency and avoidance of toxicity in the majority of CHD patients. Finally, knowledge gaps regarding vitamin D supplementation are identified and the next stages for research are outlined.