Development and validation of a predictive model of the hospital cost associated with bariatric surgery

Hospitals are facing difficulties in predicting, evaluating, and managing cost-affecting parameters in patient treatments. Inaccurate cost prediction leads to a deficit in operational revenue. This study aims to determine the ability of Machine Learning (ML) algorithms to predict the cost of care in bariatric and metabolic surgery and develop a predictive tool for improved cost analysis. 602 patients who underwent bariatric and metabolic surgery at Wetzikon hospital from 2013 to 2019 were included in the study. Multiple variables including patient factors, surgical factors, and post-operative complications were tested using a number of predictive modeling strategies. The study was registered under Req 2022-00659 and approved by an institutional review board. The cost was defined as the sum of all costs incurred during the hospital stay, expressed in CHF (Swiss Francs). The data was preprocessed and split into a training set (80%) and a test set (20%) to build and validate models. The final model was selected based on the mean absolute percentage error (MAPE). The Random Forest model was found to be the most accurate in predicting the overall cost of bariatric surgery with a mean absolute percentage error of 12.7. The study provides evidence that the Random Forest model could be used by hospitals to help with financial calculations and cost-efficient operation. However, further research is needed to improve its accuracy. This study serves as a proof of principle for an efficient ML-based prediction tool to be tested on multi-center data in future phases of the study.

Influenza increases invasive meningococcal disease risk in temperate countries

OBJECTIVES

Invasive meningococcal disease (IMD) is a severe bacterial infection that displays wintertime seasonality in temperate countries. Mechanisms driving seasonality are poorly understood and may include environmental conditions and/or respiratory virus infections. We evaluated the contribution of influenza and environmental conditions to IMD risk, using standardized methodology, across multiple geographical regions.

METHODS

We evaluated 3276 IMD cases occurring between January 1999 and December 2011 in 11 jurisdictions in Australia, Canada, France and the United States. Effects of environmental exposures and normalized weekly influenza activity on IMD risk were evaluated using a case-crossover design. Meta-analytic methods were used to evaluate homogeneity of effects and to identify sources of between-region heterogeneity.

RESULTS

After adjustment for environmental factors, elevated influenza activity at a 2-week lag was associated with increased IMD risk (adjusted odds ratio (OR) per standard deviation increase 1.29; 95% confidence interval, 1.04-1.59). This increase was homogeneous across the jurisdictions studied. By contrast, although associations between environmental exposures and IMD were identified in individual jurisdictions, none was generalizable.

CONCLUSIONS

Using a self-matched design that adjusts for both coseasonality and case characteristics, we found that surges in influenza activity result in an acute increase in population-level IMD risk. This effect is seen across diverse geographic regions in North America, France and Australia. The impact of influenza infection on downstream meningococcal risk should be considered a potential benefit of influenza immunization programmes.

Decline in Decreased Cephalosporin Susceptibility and Increase in Azithromycin Resistance in Neisseria gonorrhoeae, Canada

Antimicrobial resistance profiles were determined for Neisseria gonorrhoeae strains isolated in Canada during 2010–2014. The proportion of isolates with decreased susceptibility to cephalosporins declined significantly between 2011 and 2014, whereas azithromycin resistance increased significantly during that period. Continued surveillance of antimicrobial drug susceptibilities is imperative to inform treatment guidelines.

Epidemiology of influenza-associated hospitalization in adults, Toronto, 2007/8

The purpose of this investigation was to identify when diagnostic testing and empirical antiviral therapy should be considered for adult patients requiring hospitalization during influenza seasons. During the 2007/8 influenza season, six acute care hospitals in the Greater Toronto Area participated in active surveillance for laboratory-confirmed influenza requiring hospitalization. Nasopharyngeal (NP) swabs were obtained from patients presenting with acute respiratory or cardiac illness, or with febrile illness without clear non-respiratory etiology. Predictors of influenza were analyzed by multivariable logistic regression analysis and likelihoods of influenza infection in various patient groups were calculated. Two hundred and eighty of 3,917 patients were found to have influenza. Thirty-five percent of patients with influenza presented with a triage temperature >or=38.0 degrees C, 80% had respiratory symptoms in the emergency department, and 76% were >or=65 years old. Multivariable analysis revealed a triage temperature >or=38.0 degrees C (odds ratio [OR] 3.1; 95% confidence interval [CI] 2.3-4.1), the presence of respiratory symptoms (OR 1.7; 95% CI 1.2-2.4), admission diagnosis of respiratory infection (OR 1.8; 95% CI 1.3-2.4), admission diagnosis of exacerbation of chronic obstructive pulmonary disease (COPD)/asthma or respiratory failure (OR 2.3; 95% CI 1.6-3.4), and admission in peak influenza weeks (OR 4.2; 95% CI 3.1-5.7) as independent predictors of influenza. The likelihood of influenza exceeded 15% in patients with respiratory infection or exacerbation of COPD/asthma if the triage temperature was >or=38.0 degrees C or if they were admitted in the peak weeks during the influenza season. During influenza season, diagnostic testing and empiric antiviral therapy should be considered in patients requiring hospitalization if respiratory infection or exacerbation of COPD/asthma are suspected and if either the triage temperature is >or=38.0 degrees C or admission is during the weeks of peak influenza activity.

Comparison of Two Different Programmes of Ovulation Synchronization in the Treatment of Ovarian Cysts in Dairy Cows

It was the aim of this field study to evaluate two different protocols of ovulation synchronization for the treatment of ovarian cysts and their effect on reproductive performance in dairy cows. In addition, factors with a possible influence on treatment success and pregnancy outcome as well as costs per pregnancy were analysed. The study was performed with 130 German Holsteins with ovarian cysts diagnosed on days 55 to 60 postpartum. Cows belonging to group 1 (n = 65) received a modified ovsynch protocol [day 0: 0.15 mg cloprostenol (PGF) + 0.02 mg buserelin acetate (GnRH); day 14: PGF; day 16: GnRH]. Group 2 (n = 65) was treated with the conventional ovsynch protocol (day 0: GnRH; day 7: PGF; day 9: GnRH). Timed artificial insemination was performed 20 to 24 h later. Cows without ovarian cysts served as controls. Treatment success (disappearance of the ovarian cyst) after the first ovsynch cycle was higher in group 1 (66.2%) than in group 2 (23.1%, p < 0.05). Reproductive measures in group 1 were comparable with those of the control group and, compared with group 2, were conspicuously better (66.2%, 76.9%, 83.1%, 59.5% vs. 40.0%, 50.7%, 60.0%, 27.5% for cumulative pregnancy rate after treatment cycle 1 to 3 and second service conception rate, respectively, p < 0.05). Overconditioned cows and cows with larger ovarian cysts showed a diminished treatment and pregnancy success. In group 1, costs per pregnancy were only slightly higher than in the control group (group 1: €352.44, group 2: €484.59, control group: €333.77). In conclusion, our results suggest that ovsynch protocols can be used in the treatment of ovarian cysts. The modified ovsynch protocol led to a better cure rate as well as a better reproductive performance, and was economically beneficial compared with a conventional ovsynch protocol.

Ginkgo biloba extract protects rat kidney from diabetic and hypoxic damage

Ginkgo biloba extract EGb 761 was studied for its nephroprotective effects in experimentally diabetic and hypoxic rats. Duration of streptozotocin-induced diabetes was 4 months, that of respiratoric hypoxia of the diabetic group 20 min. The daily dose of 100 mg EGb/kg bodyweight started 1 month after induction of the diabetes. EGb reduced diabetes-induced morphological alterations of the kidney such as increase in volume of glomeruli, capillary tufts, urinary space, and thickening of Bowman's capsule basement membrane. Diabetically increased immunostaining of interstitial collagenes of types I, III, and VI was diminished by the EGb extract. EGb reduced the relative total SOD activity from 163% in diabetic kidney to 46%. Additional hypoxia-induced ultrastructural damage was also diminished.

[Intolerance reactions to ionic and nonionic contrast media in cardiac diagnosis. A randomized double-blind study]

Reactions to an ionic and a nonionic contrast medium were compared in a randomized double-blind trial involving 1153 patients (897 men, 256 women; mean age 56 [18-84] years) who underwent left-heart catheterization with coronary angiography. 584 patients (group 1) received the ionic contrast medium meglumine diatrizoate (Urografin 76%), while 569 (group 2) received the nonionic iopromide (Ultravist -370). Reactions of skin and mucosae, heart and circulation, lungs and respiratory tract, as well as of the central nervous system were noted. There was no significant difference between the two groups with respect to age, weight, height, allergic predisposition, left-ventricular ejection fraction, or serum electrolyte concentrations. Mild reactions, not requiring any treatment, occurred in 108 of the 1153 patients (9.4%), 85 (14.6%) in group 1 and 23 (4%) in group 2 (P less than 0.001). Severe reaction requiring treatment occurred in eight patients of group 1 (1.4%) and 14 of group 2 (2.5%)--difference not significant. Ventricular fibrillation was more frequent among group 2 patients (four compared with one in group 1), while two of three asystoles requiring treatment occurred in group 1 patients. The results show that, while mild reactions not requiring treatment were clearly less frequent after nonionic contrast medium injection, the risk of severe reactions was not reduced by their use.