Feline comorbidities: Recognition, diagnosis and management of the cushingoid diabetic.

PRACTICAL RELEVANCE: Diabetes mellitus (DM) is a common feline endocrinopathy, and is often driven by underlying insulin resistance with associated pancreatic beta (ß)-cell dysfunction. Although spontaneous hyperadrenocorticism (HAC) with hypercortisolemia (hypercortisolism) is relatively uncommon in cats, it is a well-established cause of insulin resistance and is routinely associated with DM in this species. CLINICAL CHALLENGES: Many of the clinical signs associated with feline HAC are subtle and may be attributed to concurrent DM or the aging process. Failure to recognize HAC in the diabetic cat can impact patient wellbeing and predispose the patient to progressive compromise. Unfortunately, it can be difficult to establish a diagnosis of HAC, as test results may be influenced by poor diabetic regulation, and protocols are different to those used in canine patients. Treatment options depend on the underlying cause, and often require careful, ongoing assessment and modulation of both adrenal function and insulin requirements. However, various approaches have been shown to either improve glycemic control in cats with sustained insulin dependence, or facilitate diabetic remission. EVIDENCE BASE: This review summarizes the current literature on feline HAC, with a particular focus on cats with concurrent DM. The clinical findings that suggest HAC are discussed, along with an outline of diagnostic options and their limitations. Published outcomes for various medical options, surgical procedures and radiation therapy are provided. The authors also share their thoughts on the safe and effective management of cats with HAC and DM, with an emphasis on the anticipation and recognition of changing insulin requirements.

Prevalence and risk factors associated with systemic hypertension in dogs with spontaneous hyperadrenocorticism.

BACKGROUND: Systemic hypertension (SH) is common in dogs with hyperadrenocorticism (HAC) however there are not many studies assessing its prevalence and risk factors. OBJECTIVES: To determine the prevalence and severity of SH in dogs with HAC and its association with clinical and laboratory findings to identify potential risk factors. ANIMALS: Sixty-six client owned dogs with spontaneous HAC. METHODS: Retrospective cross-sectional study. Medical records of dogs with HAC were reviewed. Systolic blood pressure (SBP) was measured using Doppler ultrasonography. Clinical signs, physical examination findings and clinicopathologic data (CBC, serum biochemistry and electrolytes, urinalysis and urinary culture, and adrenal function tests) were reviewed for analysis. RESULTS: Prevalence of SH (≥150 mm Hg) was 82% (54/66) and prevalence of severe SH (≥180 mm Hg) was 46% (30/66). All dogs with thrombocytosis had SH (P = .002), and a platelet count ≥438 × 103 /µL was 100% specific and 61.1% sensitive to predict SH (AUC = .802, P = .001). Median potassium levels were lower in hypertensive dogs (4.1 mEq/L, range 3.1-5.4 mEq/L) than in normotensive ones (4.5 mEq/L, range 4.0-5.0 mEq/L) (P = .007). Dogs with UPC ≥ 0.5 had higher median SBP than those without proteinuria (P = .03). Dogs with concurrent diabetes mellitus seemed to have a reduced risk of SH (OR = .118, 95%CI = .022-.626, P = .02). CONCLUSIONS AND CLINICAL IMPORTANCE: Systemic hypertension is common in dogs with HAC and is frequently severe. Blood pressure should be routinely assessed in these dogs, especially if thrombocytosis, proteinuria or low potassium concentrations are present.

Epidemiological, clinical, and laboratory aspects in a case series of canine hyperadrenocorticism: 115 cases (2010-2014) / Aspectos epidemiológicos, clínicos e laboratoriais em uma série de cães com hiperadrenocorticismo: 115 casos (2010-2014)

Diseases' clinical-epidemiological characterization assists in directing the diagnosis. The objective of this study was to describe epidemiological, clinical and laboratorial aspects of a case series of canine hyperadrenocorticism (HAC). One-hundred fifteen records of dogs diagnosed by the low dose dexamethasone suppression test and/or ACTH stimulation test were evaluated. Of the cases, 81.3% were HAC ACTH-dependent and 18.7% HAC ACTH-independent. Females were more affected, representing 69.3% of the cases. The mean age was 10.3±2.5 years and 64.9% were gonadectomized. Most of the patients were small size dogs, weighting less than 10kg (73.9%). The most frequent breeds were: Poodle (27%), Dachshund (17.4%), and Yorkshire Terrier (10.4%). The most frequent clinical manifestations were polyphagia (86%), polydipsia (82.6%), polyuria (80%), abdominal enlargement (82.6%), thin skin (79.1%), muscular weakness (78.3%) and panting (74.8%). However, eventually unusual HAC-associated signs would be present in some dogs in a more important way compared with the classic disease´s clinical signs. The CBC showed neutrophilia (66%), eosinopenia (58.3%) and lymphopenia (42.6%) as main hematological abnormalities. The most common findings in serum biochemistry were increased alkaline phosphatase activity (81.74%), increased ALT activity (62.6%), hypercholesterolemia (66%) and hypertriglyceridemia (54.7%). Urinalysis revealed hyposthenuria in 14.9% and isostenuria in 13.5%; besides proteinuria in 50% of the cases. Abdominal ultrasound showed bilateral adrenal hyperplasia (92.2%) with adrenal asymmetry in 20.8% of the cases, in addition to hepatomegaly (80.9%), biliary sludge (67.8%) and hepatic hyperechogenicity (47.8%). It was concluded that small size gonadectomized female dogs, mainly Poodles and Dachshunds, presented higher frequency in the population studied, and that the main changes observed in clinical and complementary tests were polyphagia, polyuria, polydipsia, abdominal enlargement, adrenal hyperplasia, increased phosphatase alkaline and hyperlipidemia. These results corroborated to a better disease characterization at Brazil. This work concluded that the population studied resembles the profile describe in European and North American epidemiologic studies, and that the HAC dog´s clinical picture looks similar worldwide.(AU)

A caracterização clínica-epidemiológica de doenças auxilia no direcionamento do diagnóstico. O objetivo deste trabalho foi descrever aspectos epidemiológicos, clínicos e laboratoriais de uma série de casos de hiperadrenocorticismo (HAC) canino. Foram avaliados 115 prontuários de cães diagnosticados pelo teste de supressão por baixa dose de dexametasona e/ou teste de estimulação com ACTH. Os casos de HAC ACTH-dependentes representaram 81,3% da população, e 18,7% foram ACTH-independentes. As fêmeas foram mais acometidas, representando 69,3% dos casos. A média de idade foi 10,3 ± 2,5 anos e 64,9% eram gonadectomizados. A maioria dos cães foi de porte pequeno, de até 10 kg (73,9%). As raças mais frequentes foram Poodle (27%), Dachshund (17,4%) e Yorkshire (10,4%). As manifestações clínicas mais relatadas foram polifagia (86%), polidipsia (82,6%), poliúria (80%), abdome pendular (82,6%), atrofia cutânea (79,1%), fraqueza muscular (78,3%) e dispneia (74,8%). Entretanto, eventualmente sinais clínicos pouco associados ao HAC se manifestaram de forma mais importante que os sinais clássicos da doença. O hemograma revelou neutrofilia (66%), eosinopenia (58,3%) e linfopenia (42,6%) como principais alterações hematológicas. Na bioquímica sérica foi observado aumento de fosfatase alcalina (81,74% dos casos), aumento da atividade da ALT (62,6%), hipercolesterolemia (66%) e hipertrigliceridemia (54,7%). A urinálise revelou hipostenúria em 14,9% e isostenúria em 13,5%; além de proteinúria em 50% dos casos. A ecografia abdominal evidenciou hiperplasia bilateral de adrenal (92,2%) com assimetria de adrenais em 20,8% dos casos, além de hepatomegalia (80,9%), lama biliar (67,8%) e hiperecogenicidade hepática (47,8%). Concluiu-se que fêmeas castradas de pequeno porte, principalmente das raças Poodles e Dachshunds, apresentaram maior frequência na população estudada e que as principais alterações observadas clínicas e nos exames complementares foram polifagia, poliúria, polidipsia, aumento abdominal, hiperplasia da adrenal, aumento de fosfatase alcalina e hiperlipidemia. Estes resultados corroboram para melhor caracterização da doença no Brasil. Este estudo concluiu que a população estudada se assemelha ao perfil populacional de cães com HAC descrito em estudos Europeus e Norte Americanos de forma que o perfil dos casos ao redor do globo parece similar.(AU)

Investigation of adrenal and thyroid gland dysfunction in dogs with ultrasonographic diagnosis of gallbladder mucocele formation.

Gallbladder mucocele formation is an emerging disease in dogs characterized by increased secretion of condensed granules of gel-forming mucin by the gallbladder epithelium and formation of an abnormally thick mucus that can culminate in obstruction of the bile duct or rupture of the gallbladder. The disease is associated with a high morbidity and mortality and its pathogenesis is unknown. Affected dogs have a significantly increased likelihood of concurrent diagnosis of hyperadrenocorticism, hypothyroidism, and hyperlipidemia. Whether these endocrinopathies represent coincidental primary disease processes that exacerbate gallbladder mucocele formation in predisposed dogs or reflect a concurrent disruption of endocrine and lipid metabolism is unclear. In this study, we investigated a hypothesis that dogs with gallbladder mucocele formation would have a high prevalence of occult and atypical abnormalities in adrenal cortical and thyroid gland function that would suggest the presence of endocrine disruption and provide deeper insight into disease pathogenesis. We performed a case-control study of dogs with and without ultrasonographic diagnosis of gallbladder mucocele formation and profiled adrenal cortical function using a quantitative mass spectrometry-based assay of serum adrenal-origin steroids before and after administration of synthetic cosyntropin. We simultaneously profiled serum thyroid hormone concentrations and evaluated iodine sufficiency by measurement of urine iodine:creatinine ratios (UICR). The studies were complemented by histological examination of archival thyroid tissue and measurements of thyroid gland organic iodine from dogs with gallbladder mucocele formation and control dogs. Dogs with gallbladder mucocele formation demonstrated an exaggerated cortisol response to adrenal stimulation with cosyntropin. A prevalence of 10% of dogs with gallbladder mucocele formation met laboratory-based criteria for suspect or definitive diagnosis of hyperadrenocorticism. A significantly greater number of dogs with gallbladder mucocele formation had basal serum dehydroepiandrosterone (DHEAS) increases compared to control dogs. A high percentage of dogs with gallbladder mucocele formation (26%) met laboratory-based criteria for diagnosis of hypothyroidism, but lacked detection of anti-thyroglobulin antibodies. Dogs with gallbladder mucocele formation had significantly higher UICRs than control dogs. Examination of thyroid tissue from an unrelated group of dogs with gallbladder mucocele formation did not demonstrate histological evidence of thyroiditis or significant differences in content of organic iodine. These findings suggest that dogs with gallbladder mucocele formation have a greater capacity for cortisol synthesis and pinpoint DHEAS elevations as a potential clue to the underlying pathogenesis of the disease. A high prevalence of thyroid dysfunction with absent evidence for autoimmune thyroiditis suggest a disrupted thyroid hormone metabolism in dogs with gallbladder mucocele formation although an influence of non-thyroidal illness cannot be excluded. High UICR in dogs with gallbladder mucocele formation is of undetermined significance, but of interest for further study.

Canine hyperadrenocorticism associations with signalment, selected comorbidities and mortality within North American veterinary teaching hospitals.

OBJECTIVE: To describe a large population of dogs with a diagnosis of hyperadrenocorticism at the time of death in North American veterinary teaching hospitals, and to identify comorbid conditions associated with hyperadrenocorticism. MATERIALS AND METHODS: Retrospective cohort study of 1519 dogs with hyperadrenocorticism from a population of 70,574 dogs reported to the Veterinary Medical Database. Signalment, presence or absence of hyperadrenocorticism, aetiology of hyperadrenocorticism (if described), frequency of select comorbidities and causes of death were evaluated in dogs with and without hyperadrenocorticism. RESULTS: Hyperadrenocorticism was more frequent in females. Neutering was associated with a minor, but significant, increase in the odds of hyperadrenocorticism. Hyperadrenocorticism was the presumed cause of death of 393 (25∙9%) of affected dogs. When aetiology was specified (527 dogs, corresponding to 34∙7% of the cases), pituitary-dependent hyperadrenocorticism [387 (73∙4%) out of 527 dogs] was more common than functional adrenocortical tumour [136 (25∙8%) out of 527 dogs). Hyperadrenocorticism was over-represented in certain expected (miniature poodle, dachshund) and unexpected (Irish setter, bassett hound) breeds compared with the population at large. Of the select comorbidities investigated, dogs with hyperadrenocorticism were at increased risk for concurrent diabetes mellitus, urinary tract infection, urolithiasis, hypertension, gall bladder mucocoele and thromboembolic disease compared with dogs without hyperadrenocorticism. CLINICAL SIGNIFICANCE: Hyperadrenocorticism is significantly associated with certain comorbid conditions but is not a major cause of mortality in affected dogs. Documented patterns now provide targets for prospective clinical research.

Epidemiology of hyperadrenocorticism among 210,824 dogs attending primary-care veterinary practices in the UK from 2009 to 2014.

OBJECTIVES: To estimate prevalence and risk factors for diagnosis with hyperadrenocorticism in dogs attending primary-care veterinary practices in the UK from 2009 to 2014. METHODS: Cases were identified by searching the de-identified electronic patient records from UK primary-care veterinary practices participating in the VetCompass Programme. RESULTS: The estimated prevalence for hyperadrenocorticism diagnosis in dogs was 0·28% (95% confidence interval: 0·25 to 0·31). Multivariable logistic regression analysis revealed four associated risk factors: breed, breed-relative bodyweight, age and insurance status. The bichon frise had 6·5 times the odds (95% CI: 3·5 to 12·1, P<0·001) of hyperadrenocorticism compared with crossbreds. Dogs weighing more than or equal to their breed mean had 1·7 times the odds (95% CI: 1·3 to 2·3, P<0·001) of hyperadrenocorticism compared with dogs weighing less than the breed mean. Dogs aged 12·0 years and above showed 5·7 times the odds (95% CI: 3·7 to 8·7, P<0·001) of hyperadrenocorticism compared with dogs aged 6·0 to 8·9 years. Insured dogs had 4·0 times the odds (95% CI: 2·8 to 5·6, P<0·001) of hyperadrenocorticism compared with non-insured dogs. CLINICAL SIGNIFICANCE: This is the first epidemiological report of a non-referral hospital population of dogs diagnosed with hyperadrenocorticism in the UK and describes important breed, age and bodyweight associations with this disorder which may improve diagnosis and enhance understanding of the underlying pathophysiology.

Risk of concomitant malignancy in hyperfunctioning adrenal incidentalomas.

BACKGROUND: Adrenal masses are common incidental findings on radiologic imaging. The association between malignancy and hormonal hyperactivity found in incidentally discovered adrenal tumors, however, remains unclear. METHODS: A retrospective analysis of prospectively collected data from patients who underwent adrenalectomy for incidentally discovered adrenal tumors at a single institution. Outcomes and operative data were compared by univariate analysis. Area under the curve was used to analyze the effect of tumor size in predicting malignancy. RESULTS: There were 49 patients who initially presented with adrenal incidentalomas that underwent adrenalectomy. Most patients were Caucasian women with an average age of 51 ± 14 years. Of this group, 24 patients underwent resection for hyperfunctioning adrenal glands. There were no significant differences in malignancy rates between hyperfunctional and nonfunctional tumors (4.1% vs. 12.0%, P = 0.32). On final histopathology, there were four patients with adrenal malignancies: two adrenocortical carcinomas and two metastatic from renal carcinoma. Only one patient with a hyperfunctioning adrenal tumor had underlying malignancy. Overall, invasion of adjacent structures (P < 0.001), presence of lymphadenopathy (P = 0.02), metastasis (P = 0.03), irregular tumor margins (P = 0.01), heterogeneity (P = 0.05), and tumor size >6 cm (P = 0.04) on radiologic imaging were strongly associated with malignancy in adrenal incidentalomas. CONCLUSIONS: The risk of concomitant malignancy and hormonal hyperactivity in adrenal incidentalomas is very low. Tumor size (>6 cm) and radiographic features remain the most important predictors of adrenal malignancy, regardless of tumor function.

Influence of adrenal subclinical hypercortisolism on hypertension in patients with adrenal incidentaloma.

OBJECTIVE: The purpose of our study was to clarify whether subtle cortisol-producing tumors, such as not only subclinical Cushing's syndrome (SubCS) but also subclinical hypercortisolism (SH), influence the prevalence of hypertension, since numerous basic research studies have noted that glucocorticoid excess influences blood pressure. METHODS: 80 patients with adrenocortical adenomas (39 women and 41 men; mean age 62.1 years) were enrolled. SubCS was diagnosed using a diagnostic criteria, and SH was diagnosed as the presence of a serum cortisol level greater than 50 nmol/L following 1-mg dexamethasone suppression test (DST). RESULTS: SubCS, SH, or non-functioning adrenocortical adenoma (NF) was diagnosed in 14, 13, or 53 patients, respectively. The prevalence of hypertension differed significantly among the diagnoses (SubCS, 78.6%; SH, 84.6%; NF, 39.6%; P=0.002), whereas no differences in other clinical characteristics such as age, sex, or waist girth were observed. The patients with SH had an 11.7-fold increased risk (95% confidence interval: 1.9-72.7, P=0.009) and those with SubCS had a 9.5-fold increased risk (95% confidence interval: 1.9-48.3, P=0.007) for hypertension compared to those with NF using a multivariate analysis. CONCLUSION: We demonstrated that subtle cortisol-producing tumors, such as SH as well as SubCS, were an independent risk factor for hypertension. The cut-off value of the 1-mg DST would be appropriate to predict the development of hypertension.

Hyperadrenocorticism in 10 dogs with skin lesions as the only presenting clinical signs.

Ten dogs that had skin lesions as the only presenting signs of hyperadrenocorticism (HAC) and as the owners' primary complaint are described. Dogs were included if the initial examination was for skin disease, there were no signs of systemic illness on initial presentation and there was a confirmed diagnosis of HAC by specific screening tests. Dogs were excluded if they had a severe disease that might interfere with screening tests for HAC or if the screening tests were not diagnostic. There were five males and five females; six dogs were intact. Nine dogs were diagnosed at ≥7 years. Eight dogs weighed ≤10 kg. Alopecia was present in nine dogs. Eight dogs had bacterial pyoderma, five had hyperpigmentation, and four had thin skin. One dog had unresolved dermatophytosis. Skin lesions resolved after treatment in eight dogs. One dog was not treated and one was lost to follow-up. This study showed that skin lesions may be the only clinical signs of HAC. The presence of the more common clinical signs of HAC, such as a non-pruritic, truncal alopecia and/or thin skin, without any systemic signs of HAC and/or the presence of poorly responsive skin infections warrant screening for this disease.

Evaluation of coagulation status in dogs with naturally occurring canine hyperadrenocorticism.

OBJECTIVE: To determine whether or not there are differences in coagulation parameters (eg, thrombelastography [TEG], activated partial thromboplastin time [aPTT], prothrombin time [PT], and fibrinogen) among dogs with naturally occurring hyperadrenocorticism (HAC), dogs with HAC undergoing medical management, and dogs without HAC. DESIGN: Prospective, observational study. SETTING: Veterinary teaching hospital. ANIMALS: Forty-six client-owned dogs undergoing adrenal function testing. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: Nine dogs were diagnosed with HAC de novo, 19 dogs were presented for therapeutic monitoring of previously diagnosed HAC, and 18 dogs did not have HAC. Variables compared between groups were age, body weight, platelet count, mean platelet volume, serum concentrations of cholesterol, triglycerides, antithrombin, PT, aPTT, fibrinogen, and TEG parameters (eg, alpha angle, R, K, and maximum amplitude [MA]). Dogs with HAC and dogs treated for HAC had higher serum cholesterol than dogs without HAC (P < 0.05). All groups had mean MA greater than the institutional reference interval. There was a weak, positive correlation between hematocrit and MA that was independent of diagnosis (r(2) = 0.266, P = 0.004). CONCLUSIONS: The results of this study do not support the supposition that a significant difference exists in coagulation tendencies between dogs with HAC prior to treatment, dogs with HAC during treatment, and dogs without HAC. This disagreement with the classically accepted notion that HAC leads to a hypercoagulable state could be due to a couple of possibilities. Namely, the link between HAC and hypercoagulability may be relatively weak, or our findings may be the result of a type II error either as a result of a small sample size or the use of coagulation assays that are insensitive to the effects of HAC on the hemostatic system.

Gall bladder mucoceles and their association with endocrinopathies in dogs: a retrospective case-control study.

OBJECTIVE: To investigate the relationship between endocrinopathies and diagnosis of gall bladder mucocele in dogs via a retrospective case-control study. METHODS: Records of 78 dogs with a surgical or ultrasonographic diagnosis of gall bladder mucocele were examined for the presence or absence of hyperadrenocorticism, hypothyroidism and diabetes mellitus. Two age- and breed-matched controls for each gall bladder mucocele dog (156 total control dogs) were examined for the same concurrent diseases. A matched case-control analysis was performed using conditional logistic regression. RESULTS: The odds of mucocele in dogs with hyperadrenocorticism were 29 times that of dogs without hyperadrenocorticism (P=0.001; 95 per cent CI 3.8, 219.9). No difference was found between dogs with and without diabetes mellitus. Although a significant association was found between gall bladder mucocele and hypothyroidism, potential observation bias was also identifi ed. CLINICAL SIGNIFICANCE: Hyperadrenocorticoid dogs that were presented for acute illness with laboratory evidence of hepatobiliary disease should undergo evaluation for the presence of a biliary mucocele. Dogs diagnosed with a gall bladder mucocele should be screened for concurrent hyperadrenocorticism if clinical suspicion exists.

Bioelectrical impedance analysis of body fatness in childhood congenital adrenal hyperplasia and its metabolic correlates.

There is a tendency to adiposity in patients with congenital adrenal hyperplasia (CAH) despite physiological corticosteroid doses. This study investigated body fatness in children with CAH under corticosteroid replacement therapy. Seventeen children with CAH (female:male, 9:8; age range 1.6-10.5 years) and 18 controls (female:male, 9:9; age range 1.4-10.2 years) were studied. Serum lipids, leptin, insulin, anthropometry, body circumferences, skinfold thickness, and body fat ratio as measured with bioelectrical impedance analysis (BIA) were the study parameters. Weight standard deviation scores (SDS), body mass index (BMI), BMI-SDS, body circumferences, skinfold thickness, and body fat ratio were higher and leptin was positively correlated with all of the body circumference and skinfold thickness parameters as well as body fat ratio in the study group. Waist/hip ratio was lower in the study group. Body fatness is a serious problem starting in early childhood in CAH patients and further refinement of the glucocorticoid replacement regimens as well as lifestyle measures are needed.

Subclinical hypercortisolism among outpatients referred for osteoporosis.

BACKGROUND: Hypercortisolism is known to cause osteoporosis. OBJECTIVE: To evaluate the prevalence of subclinical hypercortisolism in participants referred for evaluation of osteoporosis. DESIGN: Cross-sectional study. SETTING: Two community hospitals and research institutes in Italy. PATIENTS: 219 patients without clinically overt hypercortisolism or other secondary causes of osteoporosis who were referred for evaluation of osteoporosis between January 2005 and December 2005. MEASUREMENTS: Bone mineral density was measured by using dual-energy x-ray absorptiometry, and hypercortisolism was assessed with serum cortisol levels after a dexamethasone suppression test. Also measured were 24-hour urinary free cortisol levels and midnight plasma cortisol levels. RESULTS: Seven of 65 patients with T-scores of 2.5 or less and vertebral fractures had subclinical hypercortisolism (prevalence, 10.8% [95% CI, 3.23% to 18.31%]). This prevalence was 4.8% (CI, 1.32% to 8.20%) among patients with osteoporosis. In multivariable analyses adjusted for age, sex, and body mass index, a positive dexamethasone suppression test result was associated with the presence of osteoporosis (odds ratio, 3.37 [CI, 1.78 to 6.43]; P < 0.001) and vertebral fractures (odds ratio, 1.70 [CI, 1.04 to 2.79]; P = 0.035). LIMITATIONS: The study was conducted in a referral setting; its findings may not apply to the general population. CONCLUSIONS: Subclinical hypercortisolism may be more common than is generally recognized in patients with osteoporosis in whom secondary causes of osteoporosis have been excluded.

Glucocorticoid therapy in giant cell arteritis: duration and adverse outcomes.

OBJECTIVE: To evaluate the course of glucocorticoid (GC) therapy and associated adverse events in a population-based cohort of patients with giant cell arteritis (GCA). METHODS: We identified 125 Olmsted County residents with GCA diagnosed between 1950 and 1991 and obtained followup information on the 120 patients who were diagnosed antemortem and agreed to participate in this study. Clinical variables, GC doses, and GC adverse events on each patient were recorded. The relationship between GC therapy and the development of adverse events was studied by the Cox and Anderson-Gill proportional hazards models. RESULTS: All patients were treated with GCs and responded rapidly (median initial dosage 60 mg prednisone/day). The dosage was later reduced according to the treating physicians' judgment. The median duration required to reach 7.5 mg/day was 6.5 months and the median duration required to reach 5 mg/day was 7.5 months. Relapses or recurrences occurred in 57 patients. For the 87 patients followed to discontinuation of GC therapy and permanent remission of GCA (median of 22 months), the total median dose of prednisone was 6.47 gm. Adverse events associated with GCs were recorded in 103 (86%) patients and 2 or more events occurred in 70 patients (58%). Age and higher cumulative dose of GCs were associated with the development of adverse GC side effects. CONCLUSION: GCs are therapeutically effective in GCA and the prednisone dosage was reduced to physiologic levels in three-fourths of the patients within 1 year. However, most patients developed serious adverse side effects related to GCs, indicating that less toxic therapeutic measures are needed.

Association between diabetes mellitus, hypothyroidism or hyperadrenocorticism, and atherosclerosis in dogs.

The objective of this study was to determine whether dogs with atherosclerosis are more likely to have concurrent diabetes mellitus, hypothyroidism, or hyperadrenocorticism than dogs that do not have atherosclerosis. A retrospective mortality prevalence case-control study was performed. The study group included 30 dogs with histopathological evidence of atherosclerosis. The control group included 142 dogs with results of a complete postmortem examination, a final postmortem examination diagnosis of neoplasia, and no histopathological evidence of atherosclerosis. Control dogs were frequency matched for age and year in which the postmortem examination was performed. Proportionate changes in the prevalence of diabetes mellitus, hypothyroidism, and hyperadrenocorticism were calculated by exact prevalence odds ratios (POR), 95% confidence intervals (95% CI), and P values. Multiple logistic regression analysis was used to examine the combined effects of prevalence determinants while controlling for age and year of postmortem examination. Dogs with atherosclerosis were over 53 times more likely to have concurrent diabetes mellitus than dogs without atherosclerosis (POR = 53.6; 95% CI, 4.6-627.5; P = .002) and over 51 times more likely to have concurrent hypothyroidism than dogs without atherosclerosis (POR = 51.1; 95% CI, 14.5-180.1; P < .001). Dogs with atherosclerosis were not found to be more likely to have concurrent hyperadrenocorticism than dogs that did not have atherosclerosis (POR = 1.8; 95% CI, 0.2-17.6; P = .59). Diabetes mellitus and hypothyroidism, but not hyperadrenocorticism, are more prevalent in dogs with atherosclerosis compared to dogs without atherosclerosis on postmortem examination.