The effects of different methods of accounting for observations from euthanized animals in survival analysis

The standards of reporting trials in pets (PetSORT): Explanation and elaboration

Well-designed randomized controlled trials (RCTs) provide the best evidence of the primary research designs for evaluating the effectiveness of interventions. However, if RCTs are incompletely reported, the methodological rigor with which they were conducted cannot be reliably evaluated and it may not be possible to replicate the intervention. Missing information also may limit the reader's ability to evaluate the external validity of a trial. Reporting guidelines are available for clinical trials in human healthcare (CONSORT), livestock populations (REFLECT), and preclinical experimental research involving animals (ARRIVE 2.0). The PetSORT guidelines complement these existing guidelines, providing recommendations for reporting controlled trials in pet dogs and cats. The rationale and scientific background are explained for each of the 25 items in the PetSORT reporting recommendations checklist, with examples from well-reported trials.

A retrospective multi-center study of treatment, outcome, and prognostic factors in 34 dogs with disseminated aspergillosis in Australia

BACKGROUND

Disseminated aspergillosis (DA) in dogs has a guarded prognosis and there is a lack of a gold standard treatment protocol.

OBJECTIVE

To retrospectively assess survival times and factors influencing survival times.

ANIMALS

Dogs diagnosed with DA from January 2007 to June 2017.

METHODS

Disseminated aspergillosis case data were retrieved from 13 Australian veterinary referral centers, with a diagnosis confirmed with culture or PCR. Factors influencing survival time after diagnosis were quantified using a Cox proportional hazards regression model.

RESULTS

Thirty-four dogs met the study inclusion criteria. Twenty-two dogs were treated with antifungal treatment and 12 dogs received no antifungal treatment. Accounting for censoring of dogs that were either still alive on the date of data collection or were loss to follow-up, dogs treated with itraconazole alone (n = 8) had a median survival time (MST) of 63 (95% CI: 20-272) days compared to 830 (95% CI: 267-1259) days for the n = 14 dogs that received multimodal antifungal therapy ( χ 2 test statistic 8.6; df = 1; P < .01). The daily hazard of death (DHOD) for dogs with abnormally high serum creatinine concentration at the time of diagnosis was 7.4 (95% CI: 1.9-29) times that of dogs with serum creatinine within the reference interval.

CONCLUSION AND CLINICAL IMPORTANCE

Serum creatinine concentration at the time of diagnosis is a useful prognostic indicator for survival after a diagnosis of DA. The MST for dogs treated with multimodal antifungal therapy is longer than itraconazole alone and warrant further investigation (P < .01).

A multi-centre cohort study investigating the outcome of synovial contamination or sepsis of the calcaneal bursae in horses treated by endoscopic lavage and debridement

Background

Previous studies investigating factors associated with survival following endoscopic treatment of contamination/sepsis of the calcaneal bursa are limited.

Objectives

To investigate the factors associated with survival in horses with contamination/sepsis of the calcaneal bursae treated endoscopically and to describe the bacterial isolates involved in the synovial infections.

Study design

Retrospective analysis of clinical records.

Methods

Medical records from 128 horses with contamination/sepsis of the calcaneal bursae treated by endoscopic lavage at seven equine hospitals were reviewed. A follow‐up questionnaire was used to determine survival and return to athletic performance. Descriptive statistics and Cox proportional hazards survival models were used to determine factors associated with survival.

Results

Horses underwent one (n = 107), two (n = 19), or three (n = 2) surgeries. Survival to hospital discharge was 84.4%. Univariable survival analysis revealed that administration of systemic antimicrobials prior to referral was associated with reduced mortality (hazard ratio, [HR] 0.41, 95% CI 0.18–0.91, P = 0.03). Increased mortality was associated with bone fracture/osteomyelitis (HR 2.43, 95% CI 1.12–5.26, P = 0.03), tendon involvement (≥30% cross sectional area) (HR 3.78 95% CI 1.78–8.04, P = 0.001), duration of general anaesthesia (HR 1.01, 95% CI 1.00–1.02, P = 0.04), post‐operative synoviocentesis (HR 3.18, 95% CI 1.36–7.43, P = 0.006) and post‐operative wound dehiscence (HR 2.5, 95% CI 1.08–5.65, P = 0.04). Multivariable Cox proportional hazards model revealed reduced mortality after systemic antimicrobial administration prior to referral (HR 0.25, 95% CI 0.11–0.60, P = 0.002) and increased mortality with tendinous involvement (≥30% cross‐sectional area) (HR 7.92, 95% CI 3.31–19.92, P<0.001). At follow‐up (median 30 months, range 0.25–13 years, n = 70) 87.1% horses were alive, 7.1% had been euthanised due to the calcaneal injury and 5.7% had been euthanised for unrelated reasons. From 57 horses with athletic performance follow‐up, 91.2% returned to the same/higher level of exercise, 5.3% to a lower level and 3.5% were retired due to persistent lameness of the affected limb.

Main limitations

Retrospective study and incomplete follow‐up.

Conclusion

Endoscopic treatment of contamination/sepsis of the calcaneal bursae has an 84% survival rate to hospital discharge. Tendinous involvement reduced survival whilst systemic antimicrobials administration prior to referral improved survival.

Conduct, Oversight, and Ethical Considerations of Clinical Trials in Companion Animals with Cancer: Report of a Workshop on Best Practice Recommendations

Development of effective and safe treatments for companion animals with cancer requires the collaboration of numerous animal health professionals and the full engagement of animal owners. Establishing ‘Best Practice Recommendations’ for clinical trials in veterinary oncology represents an important step toward meeting the goal of rigorous clinical trial design and conduct that is required to establish valid evidence. Likewise, optimizing patient welfare and owner education and advocacy is crucial to meet the unique ethical obligations to both owners and animals enrolled in these clinical trials and to ensure trust in the team conducting the research. To date, ‘Best Practice Recommendations’ for clinical trial conduct have not been reported for veterinary oncology. This document summarizes the consensus of a workshop held in November, 2014 to identify relevant ethical principles and to ensure responsible conduct of clinical research in companion animals with cancer. It is intended as a working document that will be updated as advances in science and ethical considerations require. To the extent possible, existing guidelines for the conduct and oversight of clinical trials in humans have been adapted for veterinary trials to avoid duplicative effort and to facilitate integration of clinical trials such that translational research with benefits for both companion animals and humans are encouraged.

Clinical factors associated with death before discharge and overall survival time in dogs with generalized megaesophagus

OBJECTIVE

To investigate the association of 6 clinical features with outcome of dogs with generalized megaesophagus.

DESIGN

Retrospective cohort study.

ANIMALS

71 client-owned dogs with radiographic evidence of generalized esophageal dilation.

PROCEDURES

Medical records were reviewed for data on signalment, age at onset of clinical signs, body weight, evidence of undernutrition, and the administration of drugs to treat or prevent esophagitis. Radiographs were reviewed for evidence of aspiration pneumonia (AP) and to calculate the relative esophageal diameter. Details of outcome were collected from the medical records and by contacting owners and referring veterinarians. The association of 6 factors with death before discharge and overall survival time was assessed.

RESULTS

Overall median survival time was 90 days. Nineteen (26.7%) patients died before discharge from the hospital. Radiographic evidence of AP was both positively associated with death before discharge and negatively associated with overall survival time. An age at onset of clinical signs of >13 months was negatively associated with overall survival time. No evidence of an association of the degree of esophageal dilation or the use of drugs to prevent or treat esophagitis with death before discharge or overall survival time was found.

CONCLUSIONS AND CLINICAL RELEVANCE

Radiographic evidence of AP and the age at onset of clinical signs were the only variables found to be significantly associated with survival time in this study, and this should be considered when advising on prognosis in dogs with megaesophagus.

Expression of epidermal growth factor receptor (EGFR) and Ki67 in feline oral squamous cell carcinomas (FOSCC)

The aims of this study were to establish expression of epidermal growth factor receptor (EGFR) and Ki67 in 67 archived biopsy samples of feline oral squamous cell carcinomas (FOSCCs) and to establish if the expression of either markers was predictive of survival. Samples were immunohistochemically labelled for the two proteins and scored. Statistical analyses of data, including Kaplan-Meier survival curves, were performed. All samples expressed both markers although levels differed between samples. Median overall survival was 46 days and 1-year survival was 5%. There was no correlation between Ki67 and EGFR scores (Pearson's correlation coefficient, P = 0.861). Low cellular proliferation (low Ki67 score) was positively correlated with an overall longer survival (Log Rank, P = 0.02) and a trend towards better survival for the high EGFR group was observed (Log Rank, P = 0.076). Ki67 and EGFR immunostaining in FOSCC may be of value as biochemical markers for screening of biopsies from cases of FOSCC.

A retrospective study of clinical findings, treatment and outcome in 143 dogs with pericardial effusion

A retrospective study of 143 dogs with pericardial effusion is presented, including a statistical analysis of survival time. Cases were classified into those in which a mass was seen on echocardiography (echo-positive) and those in which no mass could be identified (echo-negative). Forty-four dogs were echo-positive and 99 were echo-negative. The median survival time (MST) was 1068 days for echo-negative dogs and 26 days for echo-positive dogs. Dogs with a history of collapse were more likely to present with a mass on echocardiography. Those presenting with collapse had an MST of 30 days compared with 605 days for those without collapse. Echo-negative dogs tended to present with ascites and generally had a larger volume of pericardial effusion. The median survival for dogs presenting with ascites was 605 days compared with 45 days for those without ascites. Among echo-negative dogs, 64 per cent had a relapse of their effusion. Subtotal pericardiectomy was performed in 31 echo-negative dogs. The procedure had a perioperative mortality of 13 per cent but provided a favourable long-term prognosis. Dogs undergoing pericardiectomy had a median survival of 1218 days compared with 532 days for those not undergoing surgery.