Parental practices that influence children's development: how often are they implemented and by whom-results from the NASCITA birth cohort study

This study aims to assess how commonly 15 parental practices, known to have positive effects on child and adult health, are carried out by families in Italy, if they are related, and which characteristics are associated with implementation. Children participating in the NASCITA Cohort, a prospective study in which family pediatricians in Italy collect data on children and their families, were included if they had sufficient data. Data on practice implementation, socio-demographic characteristics, and interrelatedness between practices were analyzed. In all, 3337 children were included. Their mothers had an average age at birth of 33 years (range 17-52) and medium-high levels of education (86% of mothers) and employment (72%). No smoking or alcohol in pregnancy, supine infant sleeping position, and tummy time were the most commonly implemented practices (by over 85% of mothers, each), while the least common was exclusive breastfeeding at 6 months (28%). Parental practices are related and several socio-demographic characteristics influence their implementation, with mother's educational level and geographic area of residence influencing most of the practices (each influencing 12 of 15 practices). Low educational level (OR 0.34; 95% CI 0.26-0.44), being born abroad (OR 0.43; 95% CI 0.34-0.56), and residing in the South (OR 0.49; 95% CI 0.41-0.58) most reduce the probability of implementing numerous supportive practices (all three P < 0.001).    Conclusion: Socio-demographic factors contribute significantly to carrying out supportive practices. Future interventions should address the identified inequalities, prioritizing families most in need. Direct involvement of pediatricians is warranted given their favorable position for promoting positive behaviors. What is Known: • Several parental actions in the early life of a child are known to have positive effects on later child health and development. • While folic acid supplementation and exclusive breastfeeding have been promoted for years, other supporting actions are less well-known. What is New: • Rates of parental adherence to the different supportive actions varied greatly and actions were often scantly adopted. • Socio-demographic characteristics influenced adherence, with young, unemployed mothers with low educational levels, living in the South, or who were born abroad adhering significantly less.

National ICU Registries as Enablers of Clinical Research and Quality Improvement

OBJECTIVES

Clinical quality registries (CQRs) have been implemented worldwide by several medical specialties aiming to generate a better characterization of epidemiology, treatments, and outcomes of patients. National ICU registries were created almost 3 decades ago to improve the understanding of case-mix, resource use, and outcomes of critically ill patients. This narrative review describes the challenges, proposed solutions, and evidence generated by National ICU registries as facilitators for research and quality improvement.

DATA SOURCES

English language articles were identified in PubMed using phrases related to ICU registries, CQRs, outcomes, and case-mix.

STUDY SELECTION

Original research, review articles, letters, and commentaries, were considered.

DATA EXTRACTION

Data from relevant literature were identified, reviewed, and integrated into a concise narrative review.

DATA SYNTHESIS

CQRs have been implemented worldwide by several medical specialties aiming to generate a better characterization of epidemiology, treatments, and outcomes of patients. National ICU registries were created almost 3 decades ago to improve the understanding of case-mix, resource use, and outcomes of critically ill patients. The initial experience in European countries and in Oceania ensured that through locally generated data, ICUs could assess their performances by using risk-adjusted measures and compare their results through fair and validated benchmarking metrics with other ICUs contributing to the CQR. The accomplishment of these initiatives, coupled with the increasing adoption of information technology, resulted in a broad geographic expansion of CQRs as well as their use in quality improvement studies, clinical trials as well as international comparisons, and benchmarking for ICUs.

CONCLUSIONS

ICU registries have provided increased knowledge of case-mix and outcomes of ICU patients based on real-world data and contributed to improve care delivery through quality improvement initiatives and trials. Recent increases in adoption of new technologies (i.e., cloud-based structures, artificial intelligence, machine learning) will ensure a broader and better use of data for epidemiology, healthcare policies, quality improvement, and clinical trials.

Differences between centers in functional outcome of patients with ADHD after 1 year from the time of diagnosis

Although the pharmacological therapy of ADHD has been widely studied, little has been done to compare the different therapeutic approaches (e.g., drug therapy vs. psychological treatments) and even less has been done to compare the outcome of the therapy between centers. This multicenter observational study aims to assess between-center variation in functional outcome of ADHD patients one year after the diagnosis, according to the treatment received. We used the Regional ADHD Registry data on 1429 patients enrolled in 16 ADHD centers in the 2011-2022 period. To evaluate the effectiveness of the therapy we used a generalized linear mixed model with the center as the random effect, including patient condition at diagnosis and center characteristics, weighting by the inverse of the propensity score of the treatment received by the patient. Between-center variation was expressed as the relative difference in odds-ratios between the observed and the expected number of patients whose condition improved, using the Clinical Global Impressions-Improvement Scale (CGI-I), and the relative 95% CI. Patients who received combined treatment were significantly more likely to improve compared to other treatment groups (65.5% vs 54.4% for methylphenidate alone, 53.4% for psychological treatment alone, or 40.5% for no therapy). Adjusted for patients and center characteristics, the log-odds ratio ranged from 0.85 (0.29-1.55 95% CI) to - 0.64 (- 1.17-- 0.18 95% CI). The mean expected probability of improvement after one year of therapy for an average patient with ADHD for each center was 47.7% in a center at the 25th percentile and 61.2% in a center at the 75th percentile of the outcome distribution after adjustments. The wide between-center variation in patient functional improvement one year after the diagnosis of ADHD could be largely explained by center-specific therapeutic approaches or attitudes. More careful and stringent work is needed to reduce differences in responses between centers, as could formal and periodic audit programs within and between centers.

Organizational Learning in Healthcare Contexts after COVID-19: A Study of 10 Intensive Care Units in Central and Northern Italy through Framework Analysis

The rapid spread of the SARS-CoV-2 virus has forced healthcare organizations to change their organization, introducing new ways of working, relating, communicating, and managing to cope with the growing number of hospitalized patients. Starting from the analysis of the narratives of healthcare workers who served in the intensive care units of 10 hospitals in Central and Northern Italy, this contribution intends to highlight elements present during the pandemic period within the investigated structures, which are considered factors that can influence the birth of organizational learning. Specifically, the data collected through interviews and focus groups were analyzed using the framework analysis method of Ritchie and Spencer. The conducted study made it possible to identify and highlight factors related to aspects of communication, relationships, context, and organization that positively influenced the management of the health emergency, favoring the improvement of the structure. It is believed that the identification of these factors by healthcare organizations can represent a valuable opportunity to rethink themselves, thus becoming a source of learning.

Continuous and early prediction of future moderate and severe Acute Kidney Injury in critically ill patients: Development and multi-centric, multi-national external validation of a machine-learning model

BACKGROUND

Acute Kidney Injury (AKI) is a major complication in patients admitted to Intensive Care Units (ICU), causing both clinical and economic burden on the healthcare system. This study develops a novel machine-learning (ML) model to predict, with several hours in advance, the AKI episodes of stage 2 and 3 (according to KDIGO definition) acquired in ICU.

METHODS

A total of 16'760 ICU adult patients from 145 different ICU centers and 3 different countries (US, Netherland, Italy) are retrospectively enrolled for the study. Every hour the model continuously analyzes the routinely-collected clinical data to generate a new probability of developing AKI stage 2 and 3, according to KDIGO definition, during the ICU stay.

RESULTS

The predictive model obtains an auROC of 0.884 for AKI (stage 2/3 KDIGO) prediction, when evaluated on the internal test set composed by 1'749 ICU stays from US and EU centers. When externally tested on a multi-centric US dataset of 6'985 ICU stays and multi-centric Italian dataset of 1'025 ICU stays, the model achieves an auROC of 0.877 and of 0.911, respectively. In all datasets, the time between model prediction and AKI (stage 2/3 KDIGO) onset is at least of 14 hours after the first day of ICU hospitalization.

CONCLUSIONS

In this study, a novel ML model for continuous and early AKI (stage 2/3 KDIGO) prediction is successfully developed, leveraging only routinely-available data. It continuously predicts AKI episodes during ICU stay, at least 14 hours in advance when the AKI episode happens after the first 24 hours of ICU admission. Its performances are validated in an extensive, multi-national and multi-centric cohort of ICU adult patients. This ML model overcomes the main limitations of currently available predictive models. The benefits of its real-world implementation enable an early proactive clinical management and the prevention of AKI episodes in ICU patients. Furthermore, the software could be directly integrated with IT system of the ICU.

Thoracic UltrasONOgraphy Reporting: The TUONO Consensus

The widespread use of the lung ultrasound (LUS) has not been followed by the development of a comprehensive standardized tool for its reporting in the intensive care unit (ICU) which could be useful to promote consistency and reproducibility during clinical examination. This work aims to define the essential features to be included in a standardized reporting tool and provides a structured model form to fully express the diagnostic potential of LUS and facilitate intensivists in the use of a LUS in everyday clinical ICU examination. We conducted a modified Delphi process to build consensus on the items to be integrated in a standardized report form and on its structure. A committee of 19 critical care physicians from 19 participating ICUs in Italy was formed, including intensivists experienced in ultrasound from both teaching hospitals and referral hospitals, and internationally renowned experts on the LUS. The consensus for 31 statements out of 33 was reached at the third Delphi round. A structured model form was developed based on the approved statements. The development of a standardized model as a backbone to report a LUS may facilitate the guidelines' application in clinical practice and increase inter-operator agreement. Further studies are needed to evaluate the effects of standardized reports in critically ill patients.

Physiologic dead space is independently associated with mortality and discharge of mechanically ventilated patients with COVID-19 ARDS: a retrospective study

Physiologic dead space is a well-established independent predictor of death in patients with acute respiratory distress syndrome (ARDS). Here, we explore the association between a surrogate measure of dead space (DS) and early outcomes of mechanically ventilated patients admitted to Intensive Care Unit (ICU) because of COVID-19-associated ARDS. Retrospective cohort study on data derived from Italian ICUs during the first year of the COVID-19 epidemic. A competing risk Cox proportional hazard model was applied to test for the association of DS with two competing outcomes (death or discharge from the ICU) while adjusting for confounders. The final population consisted of 401 patients from seven ICUs. A significant association of DS with both death (HR 1.204; CI 1.019-1.423; p = 0.029) and discharge (HR 0.434; CI 0.414-0.456; p [Formula: see text]) was noticed even when correcting for confounding factors (age, sex, chronic obstructive pulmonary disease, diabetes, PaO[Formula: see text]/FiO[Formula: see text], tidal volume, positive end-expiratory pressure, and systolic blood pressure). These results confirm the important association between DS and death or ICU discharge in mechanically ventilated patients with COVID-19-associated ARDS. Further work is needed to identify the optimal role of DS monitoring in this setting and to understand the physiological mechanisms underlying these associations.

Thoracic UltrasONOgraphy Reporting: The TUONO Study

Lung ultrasound (LUS) is a validated technique for the prompt diagnosis and bedside monitoring of critically ill patients due to its availability, safety profile, and cost-effectiveness. The aim of this work is to detect similarities and differences among LUS reports performed in ICUs and to provide a common ground for an integrated report form. We collected all LUS reports during an index week in 21 ICUs from the GiViTI network. First, we considered signs, chest areas, and terminology reported. Then, we compared different report structures and categorized them as structured reports (SRs), provided with a predefined model form, and free unstructured text reports (FTRs) that had no predetermined structure. We analyzed 171 reports from 21 ICUs, and 59 reports from 5 ICUs were structured. All the reports presented a qualitative description that mainly focused on the presence of B-lines, consolidations, and pleural effusion. Zones were defined in 66 reports (39%). In SRs, a complete examination of all the regions was more frequently achieved (96% vs. 74%), and a higher impact on therapeutic strategies was observed (17% vs. 6%). LUS reports vary significantly among different centers. Adopting an integrated SR seems to promote a systematic approach in scanning and reporting, with a potential impact on LUS clinical applications.

Tissue Penetration of Antimicrobials in Intensive Care Unit Patients: A Systematic Review-Part II

In patients that are admitted to intensive care units (ICUs), the clinical outcome of severe infections depends on several factors, as well as the early administration of chemotherapies and comorbidities. Antimicrobials may be used in off-label regimens to maximize the probability of therapeutic concentrations within infected tissues and to prevent the selection of resistant clones. Interestingly, the literature clearly shows that the rate of tissue penetration is variable among antibacterial drugs, and the correlation between plasma and tissue concentrations may be inconstant. The present review harvests data about tissue penetration of antibacterial drugs in ICU patients, limiting the search to those drugs that mainly act as protein synthesis inhibitors and disrupting DNA structure and function. As expected, fluoroquinolones, macrolides, linezolid, and tigecycline have an excellent diffusion into epithelial lining fluid. That high penetration is fundamental for the therapy of ventilator and healthcare-associated pneumonia. Some drugs also display a high penetration rate within cerebrospinal fluid, while other agents diffuse into the skin and soft tissues. Further studies are needed to improve our knowledge about drug tissue penetration, especially in the presence of factors that may affect drug pharmacokinetics.

Tissue Penetration of Antimicrobials in Intensive Care Unit Patients: A Systematic Review—Part I

The challenging severity of some infections, especially in critically ill patients, makes the diffusion of antimicrobial drugs within tissues one of the cornerstones of chemotherapy. The knowledge of how antibacterial agents penetrate tissues may come from different sources: preclinical studies in animal models, phase I–III clinical trials and post-registration studies. However, the particular physiopathology of critically ill patients may significantly alter drug pharmacokinetics. Indeed, changes in interstitial volumes (the third space) and/or in glomerular filtration ratio may influence the achievement of bactericidal concentrations in peripheral compartments, while inflammation can alter the systemic distribution of some drugs. On the contrary, other antibacterial agents may reach high and effective concentrations thanks to the increased tissue accumulation of macrophages and neutrophils. Therefore, the present review explores the tissue distribution of beta-lactams and other antimicrobials acting on the cell wall and cytoplasmic membrane of bacteria in critically ill patients. A systematic search of articles was performed according to PRISMA guidelines, and tissue/plasma penetration ratios were collected. Results showed a highly variable passage of drugs within tissues, while large interindividual variability may represent a hurdle which must be overcome to achieve therapeutic concentrations in some compartments. To solve that issue, off-label dosing regimens could represent an effective solution in particular conditions.

Effectiveness of a Multifaced Antibiotic Stewardship Program: A Pre-Post Study in Seven Italian ICUs

Multidrug resistance has become a serious threat for health, particularly in hospital-acquired infections. To improve patients’ safety and outcomes while maintaining the efficacy of antimicrobials, complex interventions are needed involving infection control and appropriate pharmacological treatments in antibiotic stewardship programs. We conducted a multicenter pre-post study to assess the impact of a stewardship program in seven Italian intensive care units (ICUs). Each ICU was visited by a multidisciplinary team involving clinicians, microbiologists, pharmacologists, infectious disease specialists, and data scientists. Interventions were targeted according to the characteristics of each unit. The effect of the program was measured with a panel of indicators computed with data from the MargheritaTre electronic health record. The median duration of empirical therapy decreased from 5.6 to 4.6 days and the use of quinolones dropped from 15.3% to 6%, both p < 0.001. The proportion of multi-drug-resistant bacteria (MDR) in ICU-acquired infections fell from 57.7% to 48.8%. ICU mortality and length of stay remained unchanged, indicating that reducing antibiotic administration did not harm patients’ safety. This study shows that our stewardship program successfully improved the management of infections. This suggests that policy makers should tackle multidrug resistance with a multidisciplinary approach based on continuous monitoring and personalised interventions.

Benchmark of Intraoperative Activity in Cardiac Surgery: A Comparison between Pre- and Post-Operative Prognostic Models

Objectives: Despite its large diffusion and improvements in safety, the risks of complications after cardiac surgery remain high. Published predictive perioperative scores (EUROSCORE, STS, ACEF) assess risk on preoperative data only, not accounting for the intraopertive period. We propose a double-fold model, including data collected before surgery and data collected at the end of surgery, to evaluate patient risk evolution over time and assess the direct contribution of surgery. Methods: A total of 15,882 cardiac surgery patients from a Margherita-Prosafe cohort study were included in the analysis. Probability of death was estimated using two logistic regression models (preoperative data only vs. post-operative data, also including information at discharge from the operatory theatre), testing calibration and discrimination of each model. Results: Pre-operative and post-operative models were built and demonstrate good discrimination and calibration with AUC = 0.81 and 0.87, respectively. Relative difference in pre- and post-operative mortality in separate centers ranged from −0.36 (95% CI: −0.44–−0.28) to 0.58 (95% CI: 0.46–0.71). The usefulness of this two-fold preoperative model to benchmark medical care in single hospital is exemplified in four cases. Conclusions: Predicted post-operative mortality differs from predicted pre-operative mortality, and the distance between the two models represent the impact of surgery on patient outcomes. A double-fold model can assess the impact of the intra-operative team and the evolution of patient risk over time, and benchmark different hospitals on patients subgroups to promote an improvement in medical care in each center.

Management and outcomes in critically ill nonagenarian versus octogenarian patients

Background

Intensive care unit (ICU) patients age 90 years or older represent a growing subgroup and place a huge financial burden on health care resources despite the benefit being unclear. This leads to ethical problems. The present investigation assessed the differences in outcome between nonagenarian and octogenarian ICU patients.

Methods

We included 7900 acutely admitted older critically ill patients from two large, multinational studies. The primary outcome was 30-day-mortality, and the secondary outcome was ICU-mortality. Baseline characteristics consisted of frailty assessed by the Clinical Frailty Scale (CFS), ICU-management, and outcomes were compared between octogenarian (80–89.9 years) and nonagenarian (> 90 years) patients. We used multilevel logistic regression to evaluate differences between octogenarians and nonagenarians.

Results

The nonagenarians were 10% of the entire cohort. They experienced a higher percentage of frailty (58% vs 42%; p < 0.001), but lower SOFA scores at admission (6 + 5 vs. 7 + 6; p < 0.001). ICU-management strategies were different. Octogenarians required higher rates of organ support and nonagenarians received higher rates of life-sustaining treatment limitations (40% vs. 33%; p < 0.001). ICU mortality was comparable (27% vs. 27%; p = 0.973) but a higher 30-day-mortality (45% vs. 40%; p = 0.029) was seen in the nonagenarians. After multivariable adjustment nonagenarians had no significantly increased risk for 30-day-mortality (aOR 1.25 (95% CI 0.90–1.74; p = 0.19)).

Conclusion

After adjustment for confounders, nonagenarians demonstrated no higher 30-day mortality than octogenarian patients. In this study, being age 90 years or more is no particular risk factor for an adverse outcome. This should be considered– together with illness severity and pre-existing functional capacity - to effectively guide triage decisions.

Trial registration

NCT03134807 and NCT03370692.

High dose coupled plasma filtration and adsorption in septic shock patients. Results of the COMPACT-2: a multicentre, adaptive, randomised clinical trial

PURPOSE

This study aimed at evaluating the efficacy and safety of high-dose (> 0.2 L/kg of treated plasma per day) coupled plasma filtration-adsorption (CPFA) in treating patients with septic shock.

METHODS

Multicentre, randomised, adaptive trial, performed in 12 Italian intensive care units (ICUs). Patients aged 14 or more, admitted to the ICU with septic shock, or had developed it during the stay were eligible. The final outcome was mortality at discharge from the last hospital at which the patient received care.

RESULTS

Between May 2015, and October 2017, 115 patients were randomised. The first interim analysis revealed a number of early deaths, prompting an unplanned analysis. Last hospital mortality was non-significantly higher in the CPFA (55.6%) than in the control group (46.2%, p = 0.35). The 90-day survival curves diverged in favour of the controls early after randomisation and remained separated afterwards (p = 0.100). An unplanned analysis showed higher mortality in CPFA compared to controls among patients without severe renal failure (p = 0.025); a dose-response relationship was observed between treated plasma volume and mortality (p = 0.010).

CONCLUSION

The COMPACT-2 trial was stopped due to the possible harmful effect of CPFA in patients with septic shock. The harmful effect, if present, was particularly marked in the early phase of septic shock. Patients not requiring renal replacement therapy seemed most exposed to the possible harm, with evidence of a dose-response effect. Until the mechanisms behind these results are fully understood, the use of CPFA for the treatment of patients with septic shock is not recommended.

PROSAFE: a European endeavor to improve quality of critical care medicine in seven countries

BACKGROUND

Long-lasting shared research databases are an important source of epidemiological information and can promote comparison between different healthcare services. Here we present PROSAFE, an advanced international research network in intensive care medicine, with the focus on assessing and improving the quality of care. The project involved 343 ICUs in seven countries. All patients admitted to the ICU were eligible for data collection.

METHODS

The PROSAFE network collected data using the same electronic case report form translated into the corresponding languages. A complex, multidimensional validation system was implemented to ensure maximum data quality. Individual and aggregate reports by country, region, and ICU type were prepared annually. A web-based data-sharing system allowed participants to autonomously perform different analyses on both own data and the entire database.

RESULTS

The final analysis was restricted to 262 general ICUs and 432,223 adult patients, mostly admitted to Italian units, where a research network had been active since 1991. Organization of critical care medicine in the seven countries was relatively similar, in terms of staffing, case mix and procedures, suggesting a common understanding of the role of critical care medicine. Conversely, ICU equipment differed, and patient outcomes showed wide variations among countries.

CONCLUSIONS

PROSAFE is a permanent, stable, open access, multilingual database for clinical benchmarking, ICU self-evaluation and research within and across countries, which offers a unique opportunity to improve the quality of critical care. Its entry into routine clinical practice on a voluntary basis is testimony to the success and viability of the endeavor.

Validation of the mean systemic filling pressure assessment with preserved arterial blood flow by comparing two methods of calculation

We developed a method for measuring in vivo venular volumes and the mean systemic filling pressure in the limbs using near-infrared spectroscopy (NIRS). We aimed to validate the NIRS methodology by comparing two independent methods of calculation based on different physiological approaches. Pressure–volumes (P–V) curves were recorded following graded venous occlusion on the forearm. Values from a P–V curves analysis model (method 1) were compared with data derived from a resistor-capacitance calculation model (method 2) based on arterial pressure and venous compliance. We tested these methods on 10 healthy participants at rest and during exercise and on 6 severely ill patients. Results from method 1 were comparable with those calculated by method 2. Venular volumes calculated using method 1 correlated linearly with those calculated using method 2 both in participants (R² = 0.98) and in patients (R² = 0.94). A good agreement between methods was shown with few values out of the range of ± 1.96 standard deviation. Our findings added mathematical consistency for the NIRS methodology validation in the venular P–V assessment with no flow interruption. Further research will be required to confirm the relevance of the methodology in the clinical setting.

A dynamic Bayesian network model for predicting organ failure associations without predefining outcomes

Critical care medicine has been a field for Bayesian networks (BNs) application for investigating relationships among failing organs. Criticisms have been raised on using mortality as the only outcome to determine the treatment efficacy. We aimed to develop a dynamic BN model for detecting interrelationships among failing organs and their progression, not predefining outcomes and omitting hierarchization of organ interactions. We collected data from 850 critically ill patients from the national database used in many intensive care units. We considered as nodes the organ failure assessed by a score as recorded daily. We tested several possible DBNs and used the best bootstrapping results for calculating the strength of arcs and directions. The network structure was learned using a hill climbing method. The parameters of the local distributions were fitted with a maximum of the likelihood algorithm. The network that best satisfied the accuracy requirements included 15 nodes, corresponding to 5 variables measured at three times: ICU admission, second and seventh day of ICU stay. From our findings some organ associations had probabilities higher than 50% to arise at ICU admittance or in the following days persisting over time. Our study provided a network model predicting organ failure associations and their evolution over time. This approach has the potential advantage of detecting and comparing the effects of treatments on organ function.

Case-mix affects calibration of cardiosurgical severity scores

BACKGROUND

Prognostic models are often used to assess the quality of healthcare. Several scores were developed to predict mortality after cardiac surgery, but none has reached optimal performance in subsequent validations. We validate the most used scores (EUROSCORE I and II, STS, and ACEF) on a cohort of cardiac-surgery patients, assessing their robustness against case-mix changes.

METHODS

The scores were validated on 14,559 patients admitted to 16 Italian cardiosurgical ICUs participating to Margherita-Prosafe project in 2014 and 2015. Calibration was assessed through Hosmer-Lemeshow Test, standardized mortality ratio, and GiViTI calibration test and belt. Discrimination was measured by the area under the ROC curve.

RESULTS

The study included 10,317 patients who were eligible to the calculation of the STS Score (4156 isolated valve, 4681 isolated CABG and 1480 single valve and CABG) which calibrated well in these subgroups. The ACEF Score and EUROSCORE I and II were available for 14,139, and 14,071 patients, respectively. EUROSCORE I significantly overestimated mortality; EUROSCORE II calibrated well overall, but underestimated mortality of patients undergoing complex surgery and non-elective ones. The ACEF Score calibrated poorly in elective and non-elective patients. Discrimination was acceptable for all models (AUC>0.70), but not for the ACEF Score.

CONCLUSIONS

Cardiac surgery scores calibrate poorly when the case-mix of validation and development samples differs. To grant reliability for benchmarking, they should be validated in the clinical settings on which they are applied and updated periodically. Advanced statistical tools are essential for the correct interpretation and application of severity scores.

Data collection and research with MargheritaTre

OBJECTIVE

MargheritaTre is an electronic health record developed by the Italian Group for the Evaluation of Interventions in Intensive Care Medicine designed to support clinical practice in intensive care units (ICUs) and ensure high-quality data for research purposes.

APPROACH

MargheritaTre was developed in collaboration with clinical experts, researchers, and IT specialists. It is currently installed in 40 ICUs and its database contains complete records of more than 65,000 patients. To facilitate data analysis, information is mostly stored in structured or partially structured form.

MAIN RESULTS

Data collected with MargheritaTre allow one to conduct research studies on complex clinical problems from manifold perspectives and with different levels of detail, such as epidemiological studies, analyses of the process of care and physiopathological investigations, at both single-organ and organism level. In this paper we describe some of the first projects based on this electronic health record to illustrate its potential for research.

SIGNIFICANCE

The MargheritaTre database is a huge and rapidly growing mine of data that will be exploited by our laboratory and shared with other groups to address complex and innovative research and clinical questions. The ultimate aim of these projects is the improvement of the quality of care and patient outcomes, through the development of expert systems integrated in the electronic health record to support clinical practice.

Mid regional pro-adrenomedullin for the prediction of organ failure in infection. Results from a single centre study

Biomarkers are widely used to confirm the presence of infection. However, it would be of the greatest importance to predict in advance the occurrence or worsening of organ dysfunction in infected patients allowing timely antibiotic escalation. This study investigates the ability of procalcitonin (PCT) and MR-proADM to predict the transition to sepsis in infected patients. The study was conducted in a neurointensive care unit over a three-month period. We included both patients with and without infection to investigate the specificity of organ dysfunction prediction in infected patients. Daily measurement of PCT and MR-proADM, SOFA, Pitt, and CPIS were performed. To measure the correlation between each biomarker and each severity score, linear mixed-effects models were developed. For each biomarker-score combination we tested the correlation of the score with the biomarker measured one and two days before, the same day, and the day after. Sixty-four critically ill patients, 31 with infection, were enrolled. The statistically significant biomarker-score combinations were PCT-SOFA, MR-proADM-SOFA, MR-proADM-Pitt, and MR-proADM-CPIS. The MR-proADM models predicting Pitt and CPIS variations with 24-hour anticipation showed the best fit. The scores increased by 0.6 ± 0.3 and 0.4 ± 0.2 for each unitary biomarker increase, respectively. The MR-proADM-SOFA combinations were equivalent when the biomarker was measured the day before or the same day (score increases were 1.5 ± 0.4 and 1.9 ± 0.4, respectively). The PCT-SOFA model had the best fit when PCT was measured the same day of the score. There was no difference in the predictive ability of the biomarker in infected and non-infected patients. This was a pivotal study conducted in a single neurointensive centre on a limited number of patients, and as such it does not provide definitive conclusions. PR-proADM predicted occurrence and worsening of organ failure in critically ill patients with and without infection. The combination with infection diagnostic biomarkers such as PCT would allow predicting evolution to sepsis in infected patients.

Sleep Disorders in Peritoneal and Haemodialysis Patients as Assessed by a Self-Administered Questionnaire

Sleep disorders have been reported as a frequent problem in dialysis patients. However, only one paper has compared the prevalence and possible causes of this complication in peritoneal (PD) and haemodialysis (HD) patients.

We surveyed 84 PD and 87 HD patients about disordered sleep using a self-administered questionnaire. Forty-nine percent of PD and 56% of HD patients reported problems sleeping. These problems were rated as severe by 29 PD and 22 HD patients. Type of disturbances involved delayed sleeping (13 PD and 32 HD, p< 0.005), interrupted sleep (32 PD and 44 HD) and early morning awakening (25 PD and 37 HD). The number of hours of sleep varied widely among patients: it was 5 and 21 minutes in PD patients with sleep disorders and 7 and 37 min in PD pts without such problems. No statistically significant relationship was evidenced between sleep disorders and age, sex, body weight, obesity, duration of dialysis, dialysis dose, self-assessed sadness, anxiety, worry, pain, pruritus, dyspnoea, restless leg syndrome, use of cigarettes, caffeine, or sleeping pills. In conclusion, sleep disorders are a frequent problem in both PD and HD patients. Apparently the relationship with demographics, dialysis dose, lifestyle and personality traits is poor. The possible role of other causes should be investigated.

The prognostic importance of chronic end-stage diseases in geriatric patients admitted to 163 Italian ICUs

BACKGROUND

The number of elderly patients undergoing major surgical interventions and then needing admission to intensive care unit (ICU) grows steadily. We investigated this issue in a cohort of 232,278 patients admitted in five years (2011-2015) to 163 Italian general ICUs.

METHODS

Surgical patients older than 75 registered in the GiViTI MargheritaPROSAFE project were analyzed. The impact on hospital mortality of important chronic conditions (severe COPD, NYHA class IV, dementia, end-stage renal disease, cirrhosis with portal hypertension) was investigated with two prognostic models developed yearly on patients staying in the ICU less or more than 24 hours.

RESULTS

44,551 elderly patients (19.2%) underwent emergency (47.3%) or elective surgery (52.7%). At least one severe comorbidity was present in 14.6% of them, yielding a higher hospital mortality (32.4%, vs. 21.1% without severe comorbidity). In the models for patients staying in the ICU 24 hours or more, cirrhosis, NYHA class IV, and severe COPD were constant independent predictors of death (adjusted odds ratios [ORs] range 1.67-1.97, 1.54-1.91, and 1.34-1.50, respectively), while dementia was statistically significant in four out of five models (adjusted ORs 1.23-1.28). End-stage renal disease, instead, never resulted to be an independent prognostic factor. For patients staying in the ICU less than 24 hours, chronic comorbidities were only occasionally independent predictors of death.

CONCLUSIONS

Our study confirms that elderly surgical patients represent a relevant part of all ICUs admissions. About one of seven bear at least one severe chronic comorbidity, that, excluding end-stage renal disease, are all strong independent predictors of hospital death.

The Hematocrit Affects the Volume of Plasma Treated With Coupled Plasma Filtration and Adsorption With Predilution

Coupled plasma filtration and adsorption (CPFA) is an extracorporeal blood purification technique proposed for the treatment of septic-shock. By removing pro- and anti-inflammatory mediators from plasma, CPFA is supposed to have a therapeutic effect on the abnormal inflammatory response seen in this condition. Recently, blood predilution with citrate solution has been adopted to prevent clotting in the CPFA circuit-one of the main problems of the technique. Taking into account the patient's hematocrit, we worked out a formula for the volume of plasma effectively treated by CPFA after predilution. Neglecting this effect, as is commonly done, introduces significant distortions in the estimation of the volume, possibly causing under-treatment. The distortion is stronger when the hematocrit and the predilution fraction are large and weaker when both values shrink. By correctly indicating the daily dose of plasma adsorption received by patients, this formula is essential for assessing the therapeutic efficacy of CPFA and, subsequently, establishing its optimal doses.

A new test and graphical tool to assess the goodness of fit of logistic regression models

A prognostic model is well calibrated when it accurately predicts event rates. This is first determined by testing for goodness of fit with the development dataset. All existing tests and graphic tools designed for the purpose suffer several drawbacks, related mainly to the subgrouping of observations or to heavy dependence on arbitrary parameters. We propose a statistical test and a graphical method to assess the goodness of fit of logistic regression models, obtained through an extension of similar techniques developed for external validation. We analytically computed and numerically verified the distribution of the underlying statistic. Simulations on a set of realistic scenarios show that this test and the well-known Hosmer-Lemeshow approach have similar type I error rates. The main advantage of this new approach is that the relationship between model predictions and outcome rates across the range of probabilities can be represented in the calibration belt plot, together with its statistical confidence. By readily spotting any deviations from the perfect fit, this new graphical tool is designed to identify, during the process of model development, poorly modeled variables that call for further investigation. This is illustrated through an example based on real data.

Corner-Space Renormalization Method for Driven-Dissipative Two-Dimensional Correlated Systems

We present a theoretical method to study driven-dissipative correlated quantum systems on lattices with two spatial dimensions (2D). The steady-state density matrix of the lattice is obtained by solving the master equation in a corner of the Hilbert space. The states spanning the corner space are determined through an iterative procedure, using eigenvectors of the density matrix of smaller lattice systems, merging in real space two lattices at each iteration and selecting M pairs of states by maximizing their joint probability. The accuracy of the results is then improved by increasing the dimension M of the corner space until convergence is reached. We demonstrate the efficiency of such an approach by applying it to the driven-dissipative 2D Bose-Hubbard model, describing lattices of coupled cavities with quantum optical nonlinearities.

A new calibration test and a reappraisal of the calibration belt for the assessment of prediction models based on dichotomous outcomes

Calibration is one of the main properties that must be accomplished by any predictive model. Overcoming the limitations of many approaches developed so far, a study has recently proposed the calibration belt as a graphical tool to identify ranges of probability where a model based on dichotomous outcomes miscalibrates. In this new approach, the relation between the logits of the probability predicted by a model and of the event rates observed in a sample is represented by a polynomial function, whose coefficients are fitted and its degree is fixed by a series of likelihood-ratio tests. We propose here a test associated with the calibration belt and show how the algorithm to select the polynomial degree affects the distribution of the test statistic. We calculate its exact distribution and confirm its validity via a numerical simulation. Starting from this distribution, we finally reappraise the procedure to construct the calibration belt and illustrate an application in the medical context.

Probable role of Brain Natriuretic Peptide (BNP) in lung hypertension secondary to scleroderma

BACKGROUND Scleroderma, when complicated with pulmonary hypertension (PHT), presents a worse prognosis; recently treatment with new drugs seems to offer good perspectives, especially in early diagnosis and treatment. The standard approach for diagnosing PHT consists in measurement of the pulmonary artery pressure (PAP) by means of echodoppler. AIM OF INVESTIGATION Aim of this work is evaluating the significance of the NT-proBNP parameter, matched to echodoppler, in diagnosing scleroderma PHT. MATERIALS AND METHODS Sixty (60) patients, who came to observation for progressive systemic sclerosis underwent echodoppler in order to measure the PAP (normal values up to 30 mmHg). NT-proBNP was determined on serum sample using ECLIA method by Modular E170 (Roche Diagnostics); manufacturer reference values for age and gender were used. Forty-three (43) patients underwent a further NT-proBNP sampling 5 days later in order to assess parameter stability. RESULTS PHT and non- PHT patients showed statistically different (p < 0,001) medians (126 vs 69 pg/ml). No pathologic values of NT-proBNP were measured in the group with PAP < 30 mmHg, while 27% of cases who had PAP between 30 and 40 showed pathologic concentrations. The positivity ratio increases to 57% in patients showing PAP > 40 mmHg. No relevant correlation (r = 0,2) was found between PAP and NT-proBNP. Mean average between the two sampling groups was 31%. CONCLUSIONS In scleroderma patients, combination of NT-proBNP and PAP seems to improve the diagnosis of pulmonary hypertension, especially in presence of borderline pulmonary pressure values. We therefore propose the biochemical observation of NT-proBNP when PAP is > 30 mmHg and in monitoring the evolution of the pathology.

Cosmological constant: a lesson from Bose-Einstein condensates

The cosmological constant is one of the most pressing problems in modern physics. We address this issue from an emergent gravity standpoint, by using an analogue gravity model. Indeed, the dynamics of the emergent metric in a Bose-Einstein condensate can be described by a Poisson-like equation with a vacuum source term reminiscent of a cosmological constant. The direct computation of this term shows that in emergent gravity scenarios this constant may be naturally much smaller than the naive ground-state energy of the emergent effective field theory. This suggests that a proper computation of the cosmological constant would require a detailed understanding about how Einstein equations emerge from the full microscopic quantum theory. In this light, the cosmological constant appears as a decisive test bench for any quantum or emergent gravity scenario.

Is influenza A(H1N1) pneumonia more severe than other community-acquired pneumonias? Results of the GiViTI survey of 155 Italian ICUs

PURPOSE

Uncertainty about the severity of the A(H1N1) pandemia persists. Information about disease severity can be obtained by investigating intensive care unit (ICU) admissions, especially when historical comparisons can be made with cases of community-acquired pneumonia (CAP).

METHODS

This prospective observational study was conducted in 155 ICUs contributing to the GiViTI national database. To assess the impact on ICU workload, the occupancy rate during the epidemic phase was compared with influenza periods in previous years. A logistic regression model was developed to assess the prognostic importance of A(H1N1) influenza.

RESULTS

The characteristics of the 319 A(H1N1) cases were similar to those reported in other studies, confirming the young age of patients (mean 43 years) and the higher prevalence among pregnant women and obese people. At the epidemic's peak (October-December 2009) the occupancy rate did not significantly differ from the same period of the previous year, and was significantly lower than the 2009 seasonal influenza outbreak (January-March 2009). Compared with CAP of other origin (3,678 patients), A(H1N1) pneumonia was associated with a lower risk of death. However, after adjusting for confounding this was no longer the case (OR 0.88; 95% CI 0.59-1.31; p = 0.52).

CONCLUSION

This study confirmed the specific features of critically ill A(H1N1) patients (i.e., young age, pregnancy, obesity). The pandemic did not increase ICU workload compared with other periods. A(H1N1) pneumonia did not have a higher risk of death than CAP of different origin among patients admitted to the ICU.

Calibration belt for quality-of-care assessment based on dichotomous outcomes

Prognostic models applied in medicine must be validated on independent samples, before their use can be recommended. The assessment of calibration, i.e., the model's ability to provide reliable predictions, is crucial in external validation studies. Besides having several shortcomings, statistical techniques such as the computation of the standardized mortality ratio (SMR) and its confidence intervals, the Hosmer-Lemeshow statistics, and the Cox calibration test, are all non-informative with respect to calibration across risk classes. Accordingly, calibration plots reporting expected versus observed outcomes across risk subsets have been used for many years. Erroneously, the points in the plot (frequently representing deciles of risk) have been connected with lines, generating false calibration curves. Here we propose a methodology to create a confidence band for the calibration curve based on a function that relates expected to observed probabilities across classes of risk. The calibration belt allows the ranges of risk to be spotted where there is a significant deviation from the ideal calibration, and the direction of the deviation to be indicated. This method thus offers a more analytical view in the assessment of quality of care, compared to other approaches.

Multiple sclerosis and celiac disease: is there an increased risk?

Multiple sclerosis and celiac disease are both considered immune-mediated diseases. Recently, improved serological screening methods provided a higher prevalence of celiac disease (CD) in the general population worldwide and also demonstrated gastrointestinal symptoms may be lacking. The aim of this study was to determine the prevalence of (CD) in an unselected group of 95 adults with multiple sclerosis using transglutaminase antibodies. No patients showed pathological values. Different immune and genetic basis between the two diseases may represent crucial insights to explain our results.

Influence of hepatitis B virus virema upon serum aminotransferase activity in dialysis population

BACKGROUND

The control of the spread of hepatitis B virus (HBV) infection within dialysis units has been one of the major advances in the management of patients with end-stage renal disease (ESRD). However, clinical and biochemical expression of HBV in dialysis patients have not been adequately addressed. Elevated values of serum aminotransferase activity are a sensitive measure of hepatocellular injury, but the role of HBV infection in the development of liver disease among dialysis patients has not been adequately analysed. Also, the clinical impact related to the virological characteristics of HBV in dialysis has not been evaluated.

METHODS

Demographic, biochemical and virological data from 727 patients undergoing chronic dialysis in seven dialysis units in northern Italy were collected in order to assess the biochemical consequences related to the presence of HBV infection in this population. We have measured by RT-PCR technology the titers of HBV viremia in HBsAg positive patients receiving dialysis.

RESULTS

Univariate analysis showed that AST and ALT values were significantly higher in HBsAg positive/HBV DNA positive than HBsAg negative patients on dialysis; AST, 22.86+/-31.34 vs. 14.19+/-9.7 IU/L (P=0.00001); and ALT, 25.07+/-41.59 vs. 13.9+/-41.59 IU/L (P=0.00001). In the subgroup of HBsAg positive patients, the frequency of detectable HBeAg in serum was 14.9% (7/47). The median value of HBV DNA in patients with detectable HBV DNA in serum was 2.160 x 10(3) copies/mL (range, 2.5 x 10(2)-4 x 10(6) copies/mL). HBsAg positive/HCV positive patients had higher aminotransferase activity than other subgroups (P=0.0001). Multivariate analysis showed a significant and independent association between detectable HBsAg/HBV DNA in serum and AST (P=0.00001) and ALT (P=0.0001) activity AST and ALT levels were lower in dialysis than healthy individuals--this finding persisted in age- and gender-matched comparisons.

CONCLUSIONS

The HBV viral load in HBsAg positive patients receiving maintenance dialysis is not high. HBsAg positivity with detectable HBV DNA in serum is a strong and independent predictor of raised aminotransferase activity among dialysis patients. HBsAg positive patients had greater aminotransferase activity than HBsAg negative individuals even if both the groups had mean aminotransferase levels within the normal range considered for healthy population. Clinical trials aimed at identifying the best cut-off value to enhance the diagnostic yield of AST/ALT for detecting HBV in dialysis population are under way.

[Natural history of hepatitis B virus infection in dialysis patients: prospective study by quantitative analysis of HBV viremia]

BACKGROUND

The natural history of hepatitis B virus (HBV) infection in patients undergoing maintenance dialysis is still unclear. The aim of this study was to measure the HBV viral load (HBV DNA) in a cohort (n=20) of HBsAg positive chronic dialysis patients over a 12-month observation period. METHODS; HBV DNA was measured by the Amplicor HBV MonitorTM Test Kit, an in vitro test that utilizes Polymerase Chain Reaction (PCR) nucleic acid amplification and DNA hybridisation for the quantitative measurement of hepatitis B viral DNA in human serum. Amplicor HBV MonitorTM Test Kit amplifies a sequence in the pre-Core/Core region of the HBV genome with biotinylated and non-biotinylated oligonucleotide primers.

RESULTS

There was no significant difference between the median HBV load at the start and the end of the study, 1.85 x 104 HBV copies/ml (percentile 16.84; 6.35 x 102 - 3.5 x 106 HBV copies/ ml) and 8.5 x 103 HBV copies/ml (percentile 16.84; 5.5 x 102 - 6.38 x 105 HBV copies/ml), respectively. These serum HBV DNA levels were lower than those measured by the same test in patients with chronic hepatitis B and normal renal function (Hepatology 2000; 32: 116-23). In the group of HBsAg positive carriers on dialysis, we identified three patterns of HBV viremia over time: 1) patients (n=6) with persistent HBV DNA, 2) those (n=2) with undetectable HBV DNA and 3) those (n=12) with intermittent HBV DNA. Patients with persistent HBV DNA (median, 3.3 x 104 HBV copies/ml; percentile 16.84; 3.5 x 103 - 2.3 x 106 HBV copies/ml) had higher viral HBV load than those with intermittent HBV viremia (median, 1.2 x 103 HBV copies/ml; percentile 16.84; 3.5 x 102 - 2.3 x 104 HBV copies/ml) (p=0.0001). Patients with persistent HBV DNA had higher frequency of serum hepatitis B e antigen (HBeAg) positivity than those showing intermittent and negative HBV DNA, 50% (3/6) vs. 0% (p=0.04). The frequency of serum IgM antibody against hepatitis B core antigen (IgM anti-HBc) was higher in patients with persistent HBV DNA than those having intermittent or negative HBV DNA, 100% (6/6) vs. 33% (4/12), p=0.03. We detected no difference in aminotransferase activity between patients with persistent HBV DNA and those showing intermittent or negative HBV DNA. In the group with persistent HBV DNA, the mean difference between maximum and minimum values of HBV DNA observed in each individual patient was 6.13+/-1.25 decimal logarithm (Log10) and in patients with intermittent HBV DNA 3.87+/-1.49 Log10 (p=0.006). In the entire group, the fluctuations in HBV DNA values over time between and within individuals were not significant.

CONCLUSIONS

The viremic HBV load was low and relatively stable over a 12-month follow-up period; three patterns of HBV viremia over time were observed; 30% of the viremic patients had persistent HBV viremia, and those patients had larger viral load and higher frequency of HBeAg and anti-HBc IgM than did patients with intermittent or negative HBV DNA. Prospective studies with longer observation periods are in progress to fully understand the natural history of HBV in these immunosuppressed patients.

[Hepatopathy and hepatitis B virus infection in dialysis patients: cross-sectional study]

BACKGROUND

Control of spread of HBV infection in dialysis units in developed countries has been one of the major advances in managing end-stage renal disease (ESRD). Patients with chronic HBV, however, continue to enter the population pool of dialysis patients and transplant candidates. The clinical significance related to the presence of HBsAg in serum of dialysis patients has not been completely understood.

AIM AND METHODS

We collected demographic, biochemical and virological data from a large (n=464) population of patients on maintenance dialysis. This was done to assess the influence of virological and host factors on hepatocellular damage, as shown by serum aminotransferase activity.

RESULTS

The frequency of HBsAg positivity in our dialysis population was 8.2 % (38/464); the rate of HBsAg positive patients showing HBe antigen was 20.6% (7/34). Twenty-two (84.6%) of 26 HBsAg positive patients showed detectable HBV DNA in serum by Amplicor HBV MonitorTM Test. HBsAg positive patients had serum aminotransferase activity significantly higher than HBsAg negative individuals; GOT (AST) 25.1+/-29.9 vs. 16+/-21.5 UI/L (p=0.001), and GPT (ALT) 31.3+/-52.5 vs. 17.7+/-21.9 UIL (p=0.034). In the subset of HBsAg positive dialysis patients, those in the replicative phase HBeAg positive) had aminotransferase activity higher than HBeAg negative individuals, AST, 42.3+/-43.6 vs. 22.4+/-27.3 UI/L (p=0.097) and ALT, 49.41+/-54.7 vs. 29.17+/-55.76 UI/L (NS) respectively. We did a multivariate analysis by standard least square model on the entire patient group and we found independent and significant association between detectable HBsAg in serum and AST (p=0.0089)and ALT (p=0.0159) values. There was an independent and significant relationship between age and ALT (p=0.01).

CONCLUSIONS

In our study group, HBsAg positive patients on dialysis had serum aminotransferase activity significantly higher than that measured in HBsAg negative individuals. However, mean transaminase levels in HBsAg positive patients on dialysis were below the upper limit of normal for the reference range of healthy controls. HBsAg positive dialysis patients with active viral replication showed the greatest liver damage. Studies are in progress to understand further HBV-related liver disease in dialysis population.

[Living-donor kidney transplantation in the cyclosporine era]

BACKGROUND

Renal transplantation is the best possibile form of treatment for chronic renal failure. It offers the patient a longer life expectancy when compared to dialysis. Aim of the study was to evaluate our results with live donor transplantation and the variables that influenced the long-term patient and graft survival.

METHODS

190 patients received a live donor kidney transplantation in our Hospital between 1984 and 2000. Thirty-eight of them received a graft from an HLA identical donor, 130 from an HLA haploidentical donor, 22 from a living unrelated donor (spouse). Fourteen patients underwent a pre-emptive transplantation. Aim of the study was to evaluate which variables could influence the long-term patient and graft survival.

RESULTS

The median follow-up of recipients was 69.5 months. The 10-year patient and graft survival were 94.7% and 73.4% respectively. Graft half-life was 29.6 years. Six patients died. Twelve patients lost their graft because of vascular thrombosis and five patients because of rejection within the first six months. After the first year, 11 patients lost their graft because of chronic rejection and 4 after recurrence of the original disease. One hundred and forty-four patients are still under observation, and at the last examination their mean plasma creatinine was 2.0+/-1.1 mg/dl. At univariate statistical analysis the absence of locus DR incompatibility was associated with a trend toward a better long-term survival of both patient and graft (P=0.05), while less than one year of dialysis showed a significantly better survival rate (P < 0.01).

CONCLUSIONS

Living-donor transplantation offers an excellent long-term patient and graft survival.

Folate supplementation in peritoneal dialysis patients with normal erythrocyte folate: effect on plasma homocysteine

The possible role of folate supplementation in reducing hyperhomocysteinemia in dialysis patients has been reported in several recent papers. However, scant data are available for peritoneal dialysis patients; besides, none of these studies investigated either the role of intraerythrocyte folate concentration or the presence of side effects caused by folate administration. Sixty-six peritoneal dialysis patients with hyperhomocysteinemia (>15 micromol/l) and normal folate status (as assessed by erythrocyte folate level >600 nmol/l) were randomly allocated to receive either oral folate (5 mg/day) or no vitamin supplementation. After 2 months of therapy, patients were requested to answer a questionnaire investigating the occurrence of symptoms possibly related to folate supplementation. Twenty-nine treated patients and 30 untreated controls completed the study. In the treated patients, serum and erythrocyte folate increased significantly (p < 0.0001) (respectively from 10.6 +/- 4.9 to 237 +/- 231 nmol/l and from 1,201 +/- 297 to 2,881 +/- 294 nmol/l) to levels at the uppermost limit of detection by laboratory methods. Serum vitamin B(12) levels did not change. Plasma homocysteine levels decreased from 54 +/- 32 to 23 +/- 14 micromol/l after folate supplementation and remained unchanged in the control group. After 4 months of folate therapy, homocysteine concentration was within the normal range in 5 patients (17%) and below 30 micromol/l in the other 21 (72%). Folate therapy resulted in a decrease in homocysteine of more than 50% in 45% of the patients and decrease of more than 20% in a further 38%. No significant symptoms were reported. Thus, serum and erythrocyte folate increase confirms that normal folate levels are inadequate in dialysis patients, even if serum and erythrocyte levels before folate supplementation cannot predict the effect on homocysteine plasma levels.

Decreased serum aminotransferase activity in patients with chronic renal failure: impact on the detection of viral hepatitis

Hepatitis C virus (HCV) infection is common in the dialysis population and patients with chronic renal failure (CRF) not requiring dialysis. HCV is the most important cause of chronic liver disease in dialysis patients; however, its role has been underestimated by the lower aminotransferase activity in the dialysis population. Aminotransferase activity in patients with CRF not requiring dialysis has not been adequately addressed to date. The aim of this study is to investigate whether serum aminotransferase levels in predialysis patients with CRF are less than those obtained in healthy individuals and dialysis patients. We also analyzed the potential association between serum aminotransferase activity and demographic, clinical, and biochemical parameters. Aspartate (AST) and alanine aminotransferase (ALT) activity was greater in antibody to hepatitis C (anti-HCV)-positive than anti-HCV-negative patients with CRF not requiring dialysis (AST, 32.3 +/- 19 versus 18.1 +/- 8 IU/L [P = 0.0001]; ALT, 32.9 +/- 28 versus 17.7 +/- 11 IU/L [P = 0.00001], respectively). Predialysis patients with CRF had lower AST and ALT activity in comparison to healthy individuals (AST, 19.7 +/- 11.2 versus 20.4 +/- 6.8 IU/L [P = 0.00001]; ALT, 19.5 +/- 15.1 versus 21.7 +/- 11.3 IU/L [P = 0.00001], respectively). The difference was much greater after correction for viral markers: AST and ALT levels in hepatitis B surface antigen (HBsAg)-negative anti-HCV-negative predialysis patients with CRF were less than those in the healthy population (AST, 17.9 +/- 8 versus 20.4 +/- 6.8 IU/L [P = 0.00001]; ALT, 17.5 +/- 10 versus 21.7 +/- 11.3 IU/L [P = 0.00001], respectively). Comparison of AST and ALT activity between age-matched healthy and predialysis seronegative CRF groups showed lower AST and ALT values in the study population. HBsAg-negative anti-HCV-negative dialysis patients had lower AST and ALT activity than seronegative predialysis patients with CRF (AST, 16.6 +/- 11.6 versus 17.9 +/- 8 IU/L [P = 0.01]; ALT, 16.3 +/- 9.4 versus 17.5 +/- 10 [P = 0.041], respectively). Multivariate analysis in the predialysis CRF population showed an independent association between AST (P = 0.00001) and ALT (P = 0.00001) activity and anti-HCV positivity, and age was negatively linked to AST (P = 0.011) and ALT levels (P = 0.001). AST level was negatively related to serum creatinine level (P = 0.0001). In conclusion, HCV infection causes significant liver injury in predialysis patients with CRF. These patients have decreased aminotransferase activity compared with the general population. Dialysis patients show lower aminotransferase activity than predialysis patients with CRF. Because serum aminotransferase levels are commonly used to screen for liver disease in the dialysis and predialysis CRF population, recognition of liver damage may be hampered by the reduction in aminotransferase values in these patients. Studies aimed to clarify the pathogenesis of this phenomenon are in progress.

Serum cardiac troponin I after conventional and minimal invasive coronary artery bypass surgery

We evaluated myocardial release of cardiac troponin I (cTnI) in patients treated with conventional coronary artery bypass grafting (CABG), which employs extracorporeal circulation, and different kinds of minimal invasive coronary artery bypass grafting (MICABG), a surgical technique where the operation is performed without extra-corporeal circulation. Furthermore, we evaluated the usefulness of serum cTnI measurement to detect perioperative myocardial infarction (PMI) after coronary artery bypass surgery. Thirty-one patients were included: sixteen underwent CABG, fifteen underwent different MICABG and five patients had PMI. Blood specimens for cTnI measurements were collected up to 72 hours after opening the graft. Aortic cross-clamping time was a minor determinant of myocardial damage; on the other side, the trauma during surgery correlated with the number of involved arteries and with the manoeuvre employed to obtain heart dislocation, and appeared a more important determinant of myocardial damage. In patients with PMI, the cumulative release of cTnI was higher than in patients free from PMI; however, only after 24-72 hours we observed significant differences in serum cTnI values, because the increased perioperative values of cTnI complicated the interpretation of the myocardial status and a single cut-off could not be used to exclude PMI.

Homocysteine, vitamin B12, serum and erythrocyte folate in peritoneal dialysis patients

Plasma homocysteine (tHcy) is an important risk factor for atherosclerosis in dialysis patients. Few data were reported on the prevalence and severity of hyperhomocysteinemia in peritoneal dialysis (PD) patients. In addition, little attention was paid to the search of factors possibly involved in the pathogenesis of hyperhomocysteinemia in these patients. A cross-sectional study was performed in 107 stable PD patients. None of them was given folate or vitamin B12 supplementation before or during the study. Plasma tHcy, serum vitamin B12, serum and erythrocyte folate were measured by immunoenzymatic methods. Genetic analysis of the methylentetrahydrofolate-reductase thermolabile mutation (tMTHFR) was performed in 61 patients. 97% of patients had tHcy levels higher than normal. tHcy was not different between men and women, patients with or without malnutrition, with or without clinically evident atherosclerotic vasculopathy, with or without anemia. tHcy levels were significantly higher in homozygotes for the tMTHFR mutation than in patients carrying the wild type form. Significant univariate correlation was found between hyperhomocysteinemia and time since the start of dialysis, serum and erythrocyte folate and vitamin B12. The best fitted model equation was log tHcy = 108.53 + 0.1606 (duration of dialysis) -1.1053 (s-F) -0.7980 (age) 0.0215 (vitamin B12). Our results agree with those reported by other authors in hemodialysis patients. Despite the large number of PD patients with normal serum vitamin B12 and folate status, the relation between tHcy and vitamin B12 or folate suggests that the supplementation of these vitamins could be useful irrespective of their serum levels, especially in younger patients or in those treated for a long period of time with peritoneal dialysis.

Healing of diabetes and vascular ulcers on switching from peritoneal dialysis to hemodialysis

Vascular complications are the main problem in diabetic patients and can be worsened by continuous ambulatorial peritoneal dialysis (CAPD). A 46-year old woman with a family history of diabetes progressively developed hyperglycemia and subsequently lower limb ulcers after beginning CAPD. Hypertonic bags were required to control fluid balance. On account of the severe and painful ulcers, the patient was changed to hemodialysis. Within a few weeks her diabetes improved and the vascular ulcers healed completely.

Preliminary evaluation of incremental peritoneal dialysis in 25 patients

BACKGROUND

Incremental dialysis has been suggested for patients with some residual renal function. However, very little published clinical data exist on the feasibility of this schedule.

OBJECTIVES

To assess feasibility of incremental dialysis, with regard to its effect, complications, and impact on quality of life.

DESIGN

Pilot prospective study, not controlled.

SETTING

Nephrology division, public clinical research hospital.

PATIENTS

Twenty-five patients (19 men, mean age 61+/-13 years, body weight 63+/-11 kg) began peritoneal dialysis (the first treatment of uremia) with a single nightly exchange lasting 10 hours or 2 daily exchanges over 12 hours according to creatinine clearance and Kt/N. Patients gave informed consent and reported their work activity, degree of rehabilitation, and their quality of life by answering a questionnaire prepared for this purpose.

OUTCOME MEASURES

Survival rate, complications related to peritoneal dialysis, and residual renal and peritoneal clearances.

RESULTS

During the study period no patient died. Complications related to dialysis were peritonitis (0.41 episodes/year) and exit-site infection (0.32 episodes/year). All patients continued to work with full rehabilitation and considered 1 or 2 exchanges per day less troublesome than 3 or 4.

CONCLUSIONS

Incremental dialysis is well accepted by patients and staff. This technique does not involve a high risk of complications and is economical. Therefore incremental dialysis is feasible.

Sleep disorders in peritoneal and haemodialysis patients as assessed by a self-administered questionnaire

Sleep disorders have been reported as a frequent problem in dialysis patients. However, only one paper has compared the prevalence and possible causes of this complication in peritoneal (PD) and haemodialysis (HD) patients. We surveyed 84 PD and 87 HD patients about disordered sleep using a self-administered questionnaire. Forty-nine percent of PD and 56% of HD patients reported problems sleeping. These problems were rated as severe by 29 PD and 22 HD patients. Type of disturbances involved delayed sleeping (13 PD and 32 HD, p < 0.005), interrupted sleep (32 PD and 44 HD) and early morning awakening (25 PD and 37 HD). The number of hours of sleep varied widely among patients: it was 5 and 21 minutes in PD patients with sleep disorders and 7 and 37 min in PD pts without such problems. No statistically significant relationship was evidenced between sleep disorders and age, sex, body weight, obesity, duration of dialysis, dialysis dose, self-assessed sadness, anxiety, worry, pain, pruritus, dyspnoea, restless leg syndrome, use of cigarettes, caffeine, or sleeping pills. In conclusion, sleep disorders are a frequent problem in both PD and HD patients. Apparently the relationship with demographics, dialysis dose, lifestyle and personality traits is poor. The possible role of other causes should be investigated.

Homocysteine, vitamin B12, and serum and erythrocyte folate in peritoneal dialysis and hemodialysis patients

BACKGROUND

Plasma homocysteine (Hcy) is an independent risk factor for cardiovascular disease. High levels of plasma Hcy have been observed in end-stage renal disease patients. Few studies have compared peritoneal dialysis (PD) and hemodialysis (HD) patients and few data are available on erythrocyte folate (ery-F) levels in dialysis patients.

OBJECTIVES

To evaluate plasma Hcy concentrations, vitamin B12 (B12), and folate status in dialysis patients; to analyze the possible causes of high Hcy levels; to follow up changes in folate and B12 concentrations after 6 months.

DESIGN

A cross-sectional observational study.

SETTING

Nephrology division and laboratory of hematology in a university and clinical research hospital.

PATIENTS

The study included 82 patients treated with PD for 37 + 37 months and 70 patients treated with HD for 136 + 95 months. LABORATORY METHODS: Plasma Hcy was measured by the immunoenzymatic IMx Hcy FPIA method (Abbott Laboratories, Diagnostic Division, Abbott Park, IL, U.S.A.), serum folate (s-F) and ery-F by the Stratus folate fluorometric enzyme-linked assay, and B12 by the Stratus vitamin B12 fluorometric enzyme-linked assay (DADE-Behring, Newark, DE, U.S.A.).

RESULTS

Ninety-six percent of PD and 97% of HD patients had Hcy levels above the cutoff (13.5 micromol/L). Homocysteine level was higher in HD than in PD patients, while the prevalence of hyperhomocysteinemia was similar with the two techniques. Erythrocyte folate was significantly higher in PD (1333 +/- 519 pmol/L) than in HD (1049 +/-511 pmol/L, p < 0.01). Statistically significant correlations were observed between Hcy and B12, s-F, ery-F, and dialysis duration. Multivariate analysis showed a strong correlation between s-F and Hcy. After 6 months there were no differences in Hcy, B12, s-F, and ery-F levels.

CONCLUSIONS

Plasma Hcy levels were high in more than 95% of our dialysis patients, with no relation to the type of dialysis. Vitamin B12 and folate were normal in the majority of our patients. However, serum folate was the major determinant of Hcy levels. Such a relation between Hcy and folate suggests that levels of folate within the reference interval are inadequate for dialysis patients.