Survival analysis of 219 dogs with hyperadrenocorticism attending primary care practice in England

Abstract

BackgroundHyperadrenocorticism is an endocrine disease routinely encountered within primary care practice; however, few studies evaluating survival beyond diagnosis have studied this population.MethodsThis retrospective cohort study analysed the electronic patient records of 219 cases of hyperadrenocorticism from a sample of dogs attending primary care practices in England. Kaplan-Meier plots examined the cumulative survival and Cox proportional hazard regression modelling identified factors associated with the hazard of all-cause mortality.ResultsIn the analysis, 179/219 (81.7 per cent) hyperadrenocorticism cases died during the study period with a median survival time from first diagnosis of 510 days (95% CI 412 to 618 days). Trilostane was used in 94.1 per cent of cases and differentiation between pituitary-dependent and adrenal-dependent disease was made in 20.1 per cent of cases. In the multivariable analysis, dogs weighing greater than or equal to 15 kg (HR 1.51, 95% CI 1.06 to 2.15, P=0.023) and those diagnosed greater than or equal to 13 years of age (HR 3.74, 95% CI 2.29 to 6.09, P<0.001) had increased hazards of all-cause mortality. Dogs that had their initial trilostane dose increased had a favourable prognosis (HR 0.49, 95% CI 0.32 to 0.76, P=0.015).ConclusionThis study shows that survival from diagnosis of hyperadrenocorticism appears fair for many dogs and provides primary care practitioners with relatable benchmark prognostic figures.

Frequency and risk factors for naturally occurring Cushing's syndrome in dogs attendingUKprimary‐care practices

“…Survival estimates for dogs managed with trilostane from referral populations are slightly more optimistic; however, differences may exist in the dog populations, such as mean age, breed differences and other comorbidities that could account for the differences observed. Survival estimates in the current study include 48 (8.6%) dogs that did not receive treatment and could have shortened the median survival (Nagata et al 2017, Schofield et al 2019a. Additionally, survival estimates for ADH are inferior to PDH; therefore, differing proportions of ADH and PDH in these populations could account for encountered prevalence differences (Barker et al 2005, Clemente et al 2007, Helm et al 2011, Arenas et al 2014, Fracassi et al 2015, Nagata et al 2017.…”

“…The ACTH stimulation test was performed in 78.6% of incident cases and was used more than the LDDST in the present study. The ACTH stimulation test has previously been reported to be used in greater than 90% of cases within primary-care practice in the UK (O'Neill et al 2016, Schofield et al 2020. Other diagnostic tests for Cushing's syndrome were also used less frequently in the current study to previously reported benchmarking parameters (O'Neill et al 2016).…”

Update on the treatment options for canine hyperadrenocorticism

“…Differentiating between pituitary-dependent hyperadrenocorticism (PDH) and adrenal dependent-hyperadrenocorticism (ADH) is generally considered an important step in the diagnostic workup, due to the different treatment options available and the different prognostic outcomes (Behrend and others 2013). However, this differentiation was rarely recorded in a study of primary care practice (Schofield and others 2019).…”

Development and internal validation of a prediction tool to aid the diagnosis of Cushing's syndrome in dogs attending primary‐care practice

“…6,9 Other tests more suitable as screening tools, such as the urine cortisolcreatinine ratio (UCCR), are not commonly used in primary-care practice and are impacted by a high false positive rate with specificity estimates ranging from 21% to 77%. 1,10,[12][13][14] Novel methods to aid the identification of the highest risk dogs within the at-risk population are warranted to increase confidence in diagnostic blood tests through an increase of the positive predictive value, avoid unnecessary testing, and to generally aid decision-making for primary-care practitioners. A timely and correct diagnosis of Cushing's syndrome is important because of the reduced quality-of-life in affected dogs and to ensure dogs are appropriately managed while living with the disease.…”