What is the marginal cost for marginal risk in cardiac surgery?

Background. It has been shown that postoperative length of stay (LOS) correlates highly with mortality risk for cardiac surgical procedures. Similar correlations have been found for charges with LOS and costs with risk.

Methods. Postoperative LOS and risk scores were obtained, tabulated, and compiled into the five original Parsonnet risk groups for 2,589 patients who underwent cardiac operations from 1992 through 1996 at one hospital. The correlation of the group mean LOS with the group mean risk was tested.

Results. The correlation coefficient was 0.9827; 96.58% of the variance was removed using risk to predict LOS. A calculation of the difference in cost for difference in risk for cohorts of patients is developed.

Conclusions. The high correlation of mean LOS with mean risk permits calculation of marginal cost for marginal risk based on clinical data. The marginal cost is equal to the difference in variable costs for cohorts.     

Neonatal leptin levels are strongly associated with female gender, birth length, IGF-I levels and formula feeding

OBJECTIVE: To investigate predictors of circulating leptin in healthy full-term newborns and to explore the relationship with anthropometric variables, serum levels of adiponectin and the major components of the IGF system at birth. To explore whether leptin levels are regulated by breastfeeding vs. formula feeding. DESIGN: Observational cross-sectional study. PATIENTS: Three hundred and nineteen healthy full-term newborns delivered during 1999 in Athens, Greece. MEASUREMENTS: Anthropometric measurements, formula feeding information and blood samples were obtained. Leptin and adiponectin determinations were performed using a radioimmunoassay (RIA). RESULTS: Multivariate regression analyses showed that leptin levels were positively associated with female gender, newborn length, ponderal index and IGF-I levels, but not with adiponectin levels. Newborns who were fed exclusively with milk formulas had more than twice the leptin levels of those who were exclusively breastfed. CONCLUSIONS: Leptin levels are positively related to female gender and anthropometric characteristics of neonates but, contrary to studies in adults, are not correlated with adiponectin levels. We also found evidence that formula feeding imparts a considerable increase in leptin levels in newborns.     

An open trial of naltrexone in the treatment of depersonalization disorder

Depersonalization disorder (DPD) remains one of the few disorders in modern psychiatry for which no treatments are established that are even partially effective, whether pharmacological or psychotherapeutic. Depersonalization disorder is a Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition dissociative disorder characterized by a pervasive subjective sense of unreality and detachment with intact reality testing. Two recent controlled medication trials, one with lamotrigine and one with fluoxetine, failed to show efficacy. There is some evidence for dysregulation of endogenous opioid systems in depersonalization, and a few studies have suggested that opioid antagonists may have efficacy in the treatment of dissociation and depersonalization symptoms. In this prospective open treatment trial, 14 subjects were recruited and treated with naltrexone for 6 weeks to a maximum dose of 100 mg/d (first 7 subjects) or 10 weeks to a maximum dose of 250 mg/d (next 7 subjects). Mean naltrexone dose was 120 mg/d. There was an average 30% reduction of symptoms with treatment, as measured by 3 validated dissociation scales. Three patients were very much improved, and 1 patient was much improved with naltrexone treatment. These findings are potentially promising in a highly treatment-refractory disorder for which no treatment guidelines exist and warrant a randomized controlled trial.     

Elemental Diet in Steroid-Dependent and Steroid-Refractory Crohn''s Disease

Sixteen patients with Crohn's disease who had symptoms uncontrolled by high-dose steroids (n = 11) or symptoms invariably appearing on reduction or withdrawal of immunosuppressive therapy (n = 5) were treated with elemental diet. After 4 wk of dietary treatment, 10 patients were in remission and off all medication. Seven continued to be well without treatment for a minimum of 6 months, and four for at least 1 yr. No patient who subsequently relapsed had further steroid-refractory symptoms. Of the six patients failing to respond to elemental diet, four with steroid-refractory disease required early resective surgery for symptom relief, and two continued with steroid therapy, one in much reduced dosage. Elemental diet can bring about a sustained remission in many patients with Crohn's disease dependent on or refractory to corticosteroids, and reduce the need for surgical intervention.     

Alterations in the supraspinatus tendon at MR imaging: correlation with histopathologic findings in cadavers

To determine the histopathologic correlates of alterations in the rotator cuff at magnetic resonance (MR) imaging, 13 cadaveric shoulders (in subjects aged 26-83 years at the time of death) underwent MR imaging in the coronal oblique plane at 1.5 T with proton-density- and T2-weighted spin-echo sequences. Areas corresponding to sites of MR imaging alterations were then examined histologically. Increased signal intensity on proton-density-weighted images (without further increased signal intensity on T2-weighted images) and an indistinct margin at the articular side of the supraspinatus tendon corresponded to eosinophilic, fibrillar, and mucoid degeneration and scarring. Areas of increased signal intensity on T2-weighted images were associated with severe degeneration and disruption of the supraspinatus tendon. Although other authors have suggested that certain MR findings are indicative of tendinitis, the histologic data in this study were not those of active inflammation but rather tendon degeneration.