Correlation research demonstrates that an inflammatory diet is a risk factor for calcium oxalate renal stone formation.

BACKGROUND AND AIMS: Previous studies have demonstrated associations between the Dietary Inflammatory Index (DII®), an analytical tool which evaluates the inflammatory potential of the diet according to the pro- and anti-inflammatory properties of its components, and renal stone formation. However, these have not comprehensively addressed important parameters such as stone type, gender, DII scores in stone formers (SFs) and healthy controls (Cs) and associations of DII with urine and blood chemistries. These were adopted as the survey parameters for the present study, the purpose of which was to test whether the contributory role of an inflammatory diet on stone formation could be further confirmed. METHODS: 97 calcium oxalate (CaOx) SFs and 63 Cs, matched for age and gender each completed a semi-quantitative food frequency questionnaire from which nutrient composition was computed. These data were used to calculate the DII® score. To control the effect of energy intake, energy-adjusted DII scores were calculated per 1000 kcal consumed (E-DII™). A single blood sample and two consecutive overnight (8h) urine samples were collected from a subset (n = 59 SFs and n = 54 Cs) of the overall number of particpants (n = 160). These were analysed for renal stone risk factors. Data were analysed using regression models fit in R software. RESULTS: E-DII scores were found to fit the data better than DII, so they were used throughout. E-DII scores were significantly more positive (more pro-inflammatory) in SFs than in controls in the combined gender group (-0.34 vs. -1.73, p < 0.0001) and separately in males (-0.43 vs. -1.78, p = 0.01) and females (-0.26 vs. - 1.61, p = 0.05). In blood, a significant negative correlation was seen between E-DII and HDL cholesterol. In urine significant positive correlations were seen between E-DII and each of calcium (ρ = 0.25, p = 0.02), phosphate (ρ = 0.48, p < 0.001), magnesium (ρ = 0.33, p < 0.0001) and uric acid (ρ = 0.27, p = 0.004) concentrations. A significant negative correlation was seen between E-DII and urinary volume ρ = -0.27, p = 0.003). There was no correlation between E-DII scores and the relative supersaturations of urinary CaOx, calcium phosphate (brushite) and uric acid. CONCLUSIONS: Our findings provide hitherto unreported quantitative evidence in support of the notion that the diet of calcium oxalate renal stone patients is significantly more pro-inflammatory than that of healthy controls.

Usefulness of Preoperative Determination of Serum MR-ProAdrenomedullin Levels to Predict the Need for Postoperative Organ Support in Abdominal Oncological Surgery.

The need for postoperative organic support is associated with patient outcomes. Biomarkers may be useful for detecting patients at risk. MR-ProADM is a novel biomarker with an interesting profile that can be used in this context. The main objective of this study was to verify whether there was an association between the preoperative serum levels of MR-ProADM and the need for organic support after elective abdominal cancer surgery, and to determine the preoperative MR-ProADM value that predicts the need for postoperative organic support. This was a multicenter prospective observational study conducted by four tertiary hospitals in Spain between 2017 and 2018. Plasma samples were collected for the quantification of MR-ProADM from adults who underwent major abdominal surgery during 2017-2018. The primary outcome was the need for organic support in the first seven postoperative days and its association with the preoperative levels of MR-ProADM, and the secondary outcome was the preoperative levels of MR-ProADM in the study population. This study included 370 patients with a mean age of 67.4 ± 12.9 years. Seventeen percent (63 patients) required some postoperative organic support measures in the first week. The mean preoperative value of MR-ProADM in patients who required organic support was 1.16 ± 1.15 nmol/L. The AUC-ROC of the preoperative MR-ProADM values associated with the need for organic support was 0.67 (95% CI: 0.59-0.75). The preoperative MR-ProADM value, which showed the best compromise in sensitivity and specificity for predicting the need for organic support, was 0.70 nmol/L. The negative predictive value was 91%. A multivariate analysis confirmed that a preoperative level of MR-ProADM ≥ 0.70 nmol/L is an independent factor associated with risk of postoperative organic support (OR 2, 6). Elevated preoperative MR-ProADM levels are associated with the need for postoperative organic support. Therefore, MR-ProADM may be a useful biomarker for perioperative risk assessment.

Understanding the Impact of the COVID-19 Pandemic on the Prenatal Care of a Group of Pregnant Hispanic Women living in Puerto Rico.

OBJECTIVE: To understand the impact of the COVID-19 pandemic on the prenatal care of pregnant Hispanic women living in Puerto Rico. METHODS: This was a cross-sectional study. The participants' profiles were determined through an online questionnaire to analyze COVID-19 related behaviors and experiences. RESULTS: Our sample comprised 131 women with an average age of 28 years (±5.3 years). Most of the population was pregnant at the time of the interview (74.8%; n = 98), and the rest were in their post-partum period. Overall, 46.5% (n = 61) of the patients indicated that their prenatal care did not change during the pandemic. In addition, 92.50% (n = 111) reported not altering their plans for breastfeeding their babies. Overall, 77.86% of the participants reported feeling scared or overwhelmed due to the current pandemic, and 97% agreed that COVID testing should be performed as a screening method in all pregnant females. CONCLUSION: Our findings describe the characteristics of pregnant Hispanic females living in Puerto Rico. The majority reported adhering adequately to their health services, with few or no changes in their prenatal care.

In-hospital cardiac arrest: Incidence, prognostic factors and results.

BACKGROUND AND AIMS: In-hospital cardiac arrest (CA) is a clinical entity with high morbidity and mortality that occurs in up to 2% of hospitalized patients. It is a public health problem with important economic, social, and medical repercussions, and as such its incidence needs to be reviewed and improved. The aim of this study was to determine the incidence of in-hospital CA, return of spontaneous circulation (ROSC), and survival rates at Hospital de la Princesa, and to define the clinical and demographic characteristics of patients with in-hospital CA. PATIENTS AND METHODS: Retrospective observational chart review of patients presenting in-hospital CA and treated by anaesthesiologists from the hospital's rapid intervention team. Data were collected over 1 year. RESULTS: Forty four patients were included in the study, of which 22 (50%) were women. Mean age was 75.7 years (±15.78 years), and incidence of in-hospital CA was 2.88 per 100,000 hospital admissions. Twenty two patients (50%) achieved ROSC and 11 patients (25%) survived until discharge home. The most prevalent comorbidity was arterial hypertension (63.64%); 66.7% of cases were not witnessed, and only 15.9% presented a shockable rhythm. CONCLUSIONS: These results are similar to those reported in other larger studies. We recommend introducing immediate intervention teams and devoting time to training hospital staff in in-hospital CA.

Spirometry and Smoking Cessation in Primary Care: The ESPIROTAB STUDY, A Randomized Clinical Trial.

This study aims to evaluate the effect of regularly reporting spirometry results during smoking cessation counseling from a primary care physician on the quit rate in adult smokers. METHODS: A randomized, two-arm intervention study was conducted at six primary care centers. A total of 350 smokers, ≥18 years of age, who consulted their primary care physician, participated in the study. At the selection visit, smokers who gave their consent to participate underwent spirometry. Subsequently, an appointment (visit 0) was scheduled to complete a nicotine dependence test, a smoking cessation motivation questionnaire, and a sociodemographic questionnaire. Participants were also offered brief, structured advice on how to quit smoking, as well as detailed information on spirometry results. Patients were then randomized and scheduled for follow-up visits at 3, 6, 12, and 24 months. Both arms received brief, structured advice and detailed information on spirometry results at visit 0. At consecutive follow-up visits, the control group only received brief, structured smoking cessation advice, while the intervention group also received information on initial spirometry results at visits 3 and 6, and a spirometry retest at visit 12. Exhaled carbon monoxide testing was used to check smoking cessation. RESULTS: The study included 350 smokers; 179 were assigned to the control group and 171 to the intervention group. Smoking cessation at one year was 24.0% in the intervention group compared to 16.2% in the control group. At two years, it was 25.2% in the intervention group and 18.4% in the control group. Overall, the adjusted odds of quitting smoking in the intervention group were 42% higher than in the control group (p = 0.018). CONCLUSIONS: Regular and detailed feedback of spirometry results with smokers increases smoking cessation. Specifically, the likelihood of quitting smoking in the intervention group is 1.42 times higher than in the control group (p = 0.018).

Prenatal Diagnosis of Vasa Previa by Routine Transvaginal Color Doppler.

The prenatal diagnosis of vasa previa is essential to achieving a safe delivery in patients who suffer from the condition. Transvaginal ultrasound with color Doppler performed at the time of a routine mid-trimester ultrasound is a valuable tool in terms of achieving a timely and accurate diagnosis of vasa previa.

Providing Ancillary Care in Clinical Research: A Case of Diffuse Large B-Cell Lymphoma during a Malaria Vaccine Trial in Equatorial Guinea.

Providing medical care for participants in clinical trials in resource-limited settings can be challenging and costly. Evaluation and treatment of a young man who developed cervical lymphadenopathy during a malaria vaccine trial in Equatorial Guinea required concerted efforts of a multinational, multidisciplinary team. Once a diagnosis of diffuse large B-cell lymphoma was made, the patient was taken to India to receive immunochemotherapy. This case demonstrates how high-quality medical care was provided for a serious illness that occurred during a trial that was conducted in a setting in which positron emission tomography for diagnostic staging, an oncologist for supervision of treatment, and an optimal therapeutic intervention were not available. Clinical researchers should anticipate the occurrence of medical conditions among study subjects, clearly delineate the extent to which health care will be provided, and set aside funds commensurate with those commitments.

[Consensus document of the Spanish Society of Intensive and Critical Care Medicine and Coronary Units (SEMICYUC), the Spanish Society of Otorhinolaryngology and Head and Neck Surgery (SEORL-CCC) and the Spanish Society of Anesthesiology and Resuscitation (SEDAR) on tracheotomy in patients with COVID-19 infection]. / Documento de consenso de la Sociedad Española de Medicina Intensiva, Crítica, y Unidades Coronarias (SEMICYUC), la Sociedad Española de Otorrinolaringología y Cirugía de Cabeza y Cuello (SEORL-CCC) y la Sociedad Española de Anestesiología y Reanimación (SEDAR) sobre la traqueotomía en pacientes con COVID-19.

The current COVID-19 pandemic has rendered up to 15% of patients under mechanical ventilation. Because the subsequent tracheotomy is a frequent procedure, the three societies mostly involved (SEMICYUC, SEDAR and SEORL-CCC) have setup a consensus paper that offers an overview about indications and contraindications of tracheotomy, be it by puncture or open, clarifying its respective advantages and enumerating the ideal conditions under which they should be performed, as well as the necessary steps. Regular and emergency situations are displayed together with the postoperative measures.

Colorenal fistula after renal tumour cryotherapy.

INTRODUCTION: Computed tomography (CT)-guided percutaneous cryoablation is increasingly utilized for renal cell carcinoma. Bowel injury is a known complication but is extremely rare. We herein present the case of a 58-year-old man diagnosed with a colorenal fistula after cryoablation of a left renal tumour. PRESENTATION OF CASE: A left renal tumour was incidentally found on abdominal CT examination performed for a slight increase in transaminases. Abdominal ultrasonography revealed a 31 × 32-mm solid, well-defined, cortical tumour at the lower pole of his left kidney. The patient was asymptomatic and had no distant metastasis. The decision was made to treat the tumour with percutaneous cryoablation, with good response to the technique. Two months later, the patient had recurrent urinary tract infections and pneumaturia. In the absence of improvement with antibiotic treatment, CT was performed and revealed a fistula connecting the descending colon and renal parenchyma. The decision was made to perform surgery to repair the defect caused by percutaneous cryotherapy. DISCUSSION: To reduce adverse effects of the procedure and preserve renal function, percutaneous ablation techniques have been developed. Internal injury is a known complication and it is particularly common in cases of renal tumours located in the upper and anterior kidney. The diagnosis is based on symptoms and imaging. Most colorenal fistulas have been treated conservatively with good results. CONCLUSION: The patient recovered from surgery and was discharged with no complications.

Stress-stones-stress-recurrent stones: a self-propagating cycle? Difficulties in solving this dichotomy.

Numerous studies have reported an association between stress and urolithiasis. Although urinary risk factors have been measured in several of these, compelling evidence of a causal relationship has not been established. A shortcoming is that alterations in single urinary parameters rather than ratios and quotients, which provide a more synergistic risk evaluation, have been measured. Recently, we speculated about a possible association between chronic stress and stone recurrence. This presents an intriguing dichotomy of whether stress causes stones or vice versa, or whether they are linked in a self-propagating stress-stones-stress-recurrence cycle. We investigated the latter hypothesis in a retrospective case-control designed study in which we calculated urinary ratios and quotients which are regarded as diagnostic indicators of stone risk. These included Ca/Cr, Ox/Cr, Mg/Cr, Cit/Cr, urate/Cr and citrate-magnesium-calcium ratios, activity product quotient for calcium oxalate (CaOx) and relative supersaturation of CaOx, brushite and uric acid. Overnight urinary data from 128 participants comprising 31 first time (FS), 33 recurrent (RS) CaOx stone formers and 64 controls were used. All subjects had been previously assessed for chronic stress dimensions, as well as for stress caused by their stone episodes per se. Conditional and unconditional logistic regression (with a Bonferroni correction for multiple tests) and simple linear regression were used to analyse various components of the data. Although RS had more stressful life events, with greater intensity of perception than FS, there were no significant differences between the groups regarding any of the urinary risk factors. No significant association between stressful life events and any of the urinary ratios or quotients was observed. A direct causal link between stress and stone recurrence was not indicated. We believe that future studies should shift their focus from traditional urinary risk factors to other stone-forming mechanisms. However, we recognize that there is an inherent problem in attempting to solve the stress-stones dichotomy as it would be impossible to disentangle alterations in risk factors which arise from lifestyle stress and those arising from stone episodes themselves.

Current practice in continuous renal replacement therapy: An epidemiological multicenter study. / Manejo actual de las terapias continuas de reemplazo renal: Estudio epidemiológico multicéntrico.

OBJECTIVE: The aim of the study is to ascertain the most relevant aspects of the current management of renal replacement therapy (RRT) in critically ill patients, and to analyze renal function recovery and mortality in patients undergoing RRT. METHODS: A non-interventional three-month observational study was made in 2012, with a follow-up period of 90 days, in 21 centers in Catalonia (Spain). Demographic information, severity scores and clinical data were obtained, as well as RRT parameters. INCLUSION CRITERIA: patients aged ≥ 16 years admitted to Intensive Care Units (ICUs) and subjected to RRT. RESULTS: A total of 261 critically ill patients were recruited, of which 35% had renal dysfunction prior to admission. The main reason for starting RRT was oliguria; the most widely used RRT modality was hemodiafiltration; and the median prescribed dose at baseline was 35mL/kg/h. The median time of RRT onset from ICU admission was one day. The mortality rate at 30 and 90 days was 46% and 54%, respectively, and was associated to greater severity scores and a later onset of RRT. At discharge, 85% of the survivors had recovered renal function. CONCLUSIONS: Current practice in RRT in Catalonia abides with the current clinical practice guidelines. Mortality related to RRT is associated to later onset of such therapy. The renal function recovery rate at hospital discharge was 85% among the patients subjected to RRT.

Intravenous Ibuprofen for Treatment of Post-Operative Pain: A Multicenter, Double Blind, Placebo-Controlled, Randomized Clinical Trial.

BACKGROUND: Non-steroidal anti-inflammatory drugs are often used as components of multimodal therapy for postoperative pain management, but their use is currently limited by its side effects. The specific objective of this study was to evaluate the efficacy and safety of a new formulation of intravenous (IV) ibuprofen for the management of postoperative pain in a European population. METHODS AND FINDINGS: A total of 206 patients from both abdominal and orthopedic surgery, were randomly assigned in 1:1 ratio to receive 800 mg IV-ibuprofen or placebo every 6 hours; all patients had morphine access through a patient controlled analgesia pump. The primary outcome measure was median morphine consumption within the first 24 hours following surgery. The mean±SEM of morphine requirements was reduced from 29,8±5,25 mg to 14,22±3,23 mg (p = 0,015) and resulted in a decrease in pain at rest (p = 0,02) measured by Visual Analog Scale (VAS) from mean±SEM 3.34±0,35 to 0.86±0.24, and also in pain during movement (p = 0,02) from 4.32±0,36 to 1.90±0,30 in the ibuprofen treatment arm; while in the placebo group VAS score at rest ranged from 4.68±0,40 to 2.12±0,42 and during movement from 5.66±0,42 to 3.38±0,44. Similar treatment-emergent adverse events occurred across both study groups and there was no difference in the overall incidence of these events. CONCLUSIONS: Perioperative administration of IV-Ibuprofen 800 mg every 6 hours in abdominal surgery patient's decreases morphine requirements and pain score. Furthermore IV-Ibuprofen was safe and well tolerate. Consequently we consider appropriate that protocols for management of postoperative pain include IV-Ibuprofen 800 mg every 6 hours as an option to offer patients an analgesic benefit while reducing the potentially risks associated with morphine consumption. TRIAL REGISTRATION: EU Clinical Trials Register 2011-005007-33.

High levels of preoperative and postoperative N terminal B-type natriuretic propeptide influence mortality and cardiovascular complications after noncardiac surgery: A prospective cohort study.

BACKGROUND: Major noncardiac surgery is associated with a 5% incidence of serious cardiovascular complications and with a 1 to 2% probability of death from cardiac causes. Over the last few decades, researchers have assessed the perioperative predictive power of several risk indices. Research is currently focused on the evaluation of biomarkers. OBJECTIVES: The objective was to determine the incidence of high serum levels of N terminal B-type natriuretic propeptide (NT-proBNP) before and after surgery in adults undergoing elective major noncardiac procedures and to evaluate its relationship with mortality and cardiovascular complications occurring up to 30 days after surgery. DESIGN: Prospective cohort study. SETTING: Enrolment was undertaken at a university hospital from October 2011 to July 2013. PATIENTS: A total of 304 adults with cardiovascular risk factors who underwent noncardiac elective surgery. MAIN OUTCOME MEASURES: The relationship between preoperative and postoperative NT-proBNP serum levels and the emergence of cardiovascular complications, including all-cause mortality, during the first 30 days after surgery. RESULTS: The incidence of cardiovascular complications was 7.8% (n = 25), and the mortality rate was 4.3% (n = 13). Higher-than-normal NT-proBNP serum levels were found before surgery in 48.4% (n = 147) and after surgery in 50.7% (n = 154) of patients. The variables found to be independent predictors of cardiovascular complications, including all-cause 30-day mortality, were levels of NT-proBNP more than 300 pg ml before surgery and levels more than 1000 pg ml both before and after surgery. CONCLUSION: High levels of preoperative and postoperative NT-proBNP are predictors of cardiovascular complications, including all-cause mortality, during the first 30 days after noncardiac surgery in adults with cardiovascular risk factors.

Asthma and insulin resistance in obese children and adolescents.

BACKGROUND: Obese children and adolescents have an increased risk for asthma. A few studies have evaluated the association of insulin resistance and asthma in obese pediatric populations. We examined whether there was a relationship between high degrees of insulin resistance and the presence of asthma in obese children and adolescents. METHODS: A total of 153 patients aged 4-15 years with at or above the 95th percentile BMI for age were prospectively recruited. Assessments included diagnosis of asthma, skin prick test reactivity to common environmental aeroallergens, and HOMA estimated insulin resistance, with the median (2.22) used as a cutoff value to categorize insulin resistance. RESULTS: There were 56 (36.6%) asthmatic and 97 (63.4%) non-asthmatic patients. HOMA values were significantly associated with positive skin tests (p = 0.008) and allergic asthma diagnosis (p = 0.016). Baseline insulin value was significantly associated with the risk of presenting asthma with positive skin testing (odds ratio 1.084, p = 0.037). Differences in age, BMI, and waist circumference were found between the groups of HOMA-IR <2.22 and ≥2.22. Waist circumference (WC) was significantly associated with FVC (p = 0.0001) and FEV1 (p < 0.0003); the greater the WC, the lower FVC and FEV1 values. CONCLUSIONS: Insulin resistance is a risk for allergic asthma in obese children and adolescents. Waist circumference was related to CVF and FEV1 impairment.

Chronic stress and calcium oxalate stone disease: influence on blood cortisol and urine composition.

OBJECTIVE: To evaluate the influence of chronic stress (CS) on urine composition of calcium oxalate (CaOx) stone patients and controls. METHODS: This case-control study enrolled 128 patients during a period of 20 months. The cases were CaOx stone formers with a recent stone episode. Controls were matched by sex and age. Dimensions of CS were evaluated in cases and controls by validated self-report questionnaires measuring stressful life events, perceived stress, anxiety, depression, burnout, and satisfaction with life. Blood and urine samples were collected to determine cortisol levels and urinary composition. RESULTS: More relations between CS dimensions and blood and urine parameters were observed in cases than in controls. In cases, the blood cortisol level was related positively with the number of stressful life events (P = .03), intensity of these events (P = .04), and anxiety (P = .04). In addition, urinary magnesium (P = .03) and pyrophosphate (P = .05) levels were positively related with satisfaction with life and burnout, respectively. In contrast, urinary magnesium levels were negatively related with perceived stress (P = .01), anxiety (P = .016), and depression (P = .03). In controls, the number of stressful life events and the intensity of stressful life events was related positively with magnesium (P = .06, P = .02) levels and negatively with blood cortisol levels (P = .03, P = .004). CONCLUSION: Based on the variation between cases and controls in relations between CS dimensions and biochemical parameters, we hypothesize that CS may trigger a differential biological response in CaOx stone formers and controls, which in turn may promote or protect against CaOx stone formation.

Chronic stress and calcium oxalate stone disease: is it a potential recurrence risk factor?

Chronic emotional stress is associated with increased cortisol release and metabolism disorders. However, few studies have evaluated the influence of chronic stress on calcium oxalate (CaOx) stone disease and its recurrence. A total of 128 patients were enrolled in this case-control study over a period of 20 months. All patients were CaOx stone formers with a recent stone episode (<3 months); 31 were first-time stone formers (FS) and 33 recurrent stone formers (RS). Dimensions of chronic stress were evaluated with self-reported validated questionnaires measuring stressful life events, perceived stress, anxiety, depression, burnout and satisfaction with life. An ad hoc self-reporting questionnaire was designed to evaluate stress-related specifically to stone episodes. Blood and urine samples were collected to determine cortisol levels and urinary composition. In addition, epidemiological data, socioeconomic information, diet and incidences of metabolic syndrome (MS) were reported. Overall, no significant differences were observed in the scores of cases and controls on any of the questionnaires dealing with stress. The number (p < 0.001) and the intensity (p < 0.001) of perceived stressful life events were higher in RS than in FS, but there were no differences between the two groups in other dimensions of stress. RS had higher glucose (p = 0.08), uric acid (p = 0.02), blood cortisol (p = 0.01), and urine calcium levels (p = 0.01) than FS. RS also had lower economic levels (p = 0.02) and more frequent incidences of MS (p = 0.07) than FS. Although no differences were observed in cases and controls among any dimension of chronic stress, the number and intensity of stressful life events were higher in RS than in FS. These differences correlate with variations in blood and urinary levels and with metabolic disorders, indicating an association between chronic stress and risk of recurrent CaOx stone formation.

Comparison of conventional nighttime with automatic or manual daytime CPAP titration in unselected sleep apnea patients: study of the usefulness of daytime titration studies.

Daytime CPAP titration studies with full polysomnography have been successfully performed in patients with severe sleep apnea-hypopnea syndrome (SAHS). The implementation of daytime studies in unselected SAHS patients could help to reduce the waiting lists for CPAP titrations. The main purpose of this study was to compare the effectiveness of conventional versus manual or automatic daytime CPAP titration in unselected patients with SAHS. Ninety-three consecutive patients with SAHS in whom CPAP was indicated were assigned to conventional titration or to manual or automatic (AutoSet) daytime CPAP titration, after sleep deprivation. The number of valid studies, sleep architecture, final pressure selected and mean pressure in the different sleep stages were compared. Changes in sleepiness (Epworth sleepiness score) and hours of CPAP use were assessed after 3 months of treatment. Four patients did not sleep (3 AutoSet, 1 conventional daytime groups). Sleep latency was shorter during automatic daytime titration whereas REM latency was shorter in daytime studies; the percentage of sleep stages was similar during all types of titration. CPAP requirements were significantly higher during REM sleep in conventional and manual daytime titrations while mean pressure was unchanged throughout sleep stages during AutoSet titration. CPAP pressure selected with conventional or daytime manual titration (7.5(2.2) cm H2O and 7.4(1.5) cm H2O, ns) were significantly lower (P< 0.001) than with AutoSet (9.4(1.6) cm H20. All groups showed similar decrease of sleepiness and hours of use of CPAP at 3 months of follow-up. Automatic and manual daytime PSG studies after sleep deprivation are useful for CPAP titration in unselected patients with SAHS. Pressure selected with AutoSet is significantly higher than with conventional daytime or nighttime titration, although not significant in terms of treatment compliance and symptom improvement.

Methods for analysis of the occurrence of abscess in patients with pancreatitis.

OBJECTIVE: Standard survival analysis methods are useful for data involving censored cases when cures do not generally occur. If the object is to study, for instance, the development of a complication in the progress of an infectious disease, some people may be cured before complications develop. In this article, we provide methods for the analysis of data when cures do occur. An example is a study of prognostic factors for pancreatic abscess in patients with pancreatitis, some of whom leave the risk set because the pancreatitis clears. DESIGN: We present methods for estimating the survival curves and comparing hazard function for two objectives: (1) the occurrence of an abscess, irrespective of whether the patients are cured or not, and (2) the occurrence of an abscess for patients who, at that stage, have not been cured. PATIENTS: We illustrate the applications of the methods using a sample of 50 patients with severe pancreatitis. RESULTS: To study the occurrence of an abscess, regardless of whether the patients are cured or not, we show that the appropriate strategy is to assign to the cured patients an infinite time to the appearance of an abscess. If the cured were considered censored at the moment the pancreatitis cleared, this would result in an overestimation of the hazard of presenting an abscess. On the other hand, if the objective is to compare the occurrence of abscess according to an exposure for patients who have not been cured, one needs to censor the cured patients at the time they are cured. CONCLUSIONS: For the analysis of survival data in the context of infectious diseases when cure is possible, it is important to use a censoring strategy that is pertinent to the specific aims of the study. Considering cures as censored at the time of cure is not always appropriate.