Survival In Cats Research Articles

Diagnostic predictors of complications and survival after renal transplantation in cats.

To identify preoperative diagnostic results that predict postoperative complications and survival in feline renal-transplant recipients. Retrospective clinical study. Sixty-one feline renal allograft recipients. Medical records for 61 consecutive cats that underwent renal allograft transplantation between January 1, 1996, and December 1, 1999, were reviewed. Age, diagnosis, body weight, body condition score, preoperative medical treatment, systolic blood pressure, packed cell volume, biochemical parameters at admission and at the time of surgery, postoperative complications, and postoperative survival were recorded. Associations of preoperative data with the occurrence of postoperative complications were determined using logistic regression. Postoperative survival was graphed using a Kaplan-Meier cumulative-survival plot. Associations of covariates with postoperative survival were analyzed using Cox proportional hazards analysis. Two parameters were significantly associated with occurrence of postoperative central nervous system (CNS) disorders: blood urea nitrogen concentration (odds ratio = 1.083; 95% CI = 1.018 to 1.148) and serum creatinine concentration (odds ratio = 1.8; 95% CI = 1.413 to 2.187) at the time of surgery. Postoperative survival 6 months after transplantation was 59%, though 3-year survival remained at 42%. Of all covariates investigated, only recipient age (relative hazard = 1.183; 95% CI = 1.039 to 1.334) was significantly associated with survival. Standard measures of preoperative renal dysfunction do not predict postoperative survival in cats after renal transplantation, although an increase in the degree of preoperative azotemia is associated with an increased risk of CNS disorders after surgery. Increased recipient age is associated with decreased survival after renal transplantation.

Long-term health and predictors of survival for hyperthyroid cats treated with iodine 131.

Two hundred thirty-one cats treated with radioactive iodine at the Texas Veterinary Medical Teaching Hospital were followed for a median of 25 months by means of an ambidirectional (prospective, retrospective) cohort study design. Cox proportional hazards models were used to determine predictors of survival based on data at the time of hyperthyroid diagnosis (collected retrospectively) and found that only age at diagnosis and sex of the cat were predictors of survival. Increasing age (for each year of age, relative risk [RR] = 1.2, 95% confidence interval [CI] = 1.1-1.3) and being male (RR = 0.68, 95% CI = 0.5-0.9) increased likelihood of death. Tables predicting survival after diagnosis and treatment of hyperthyroidism for various age and sex combinations were created. In addition, Cox proportional hazard models were run with all data available at the end of the study (collected retrospectively and prospectively) including number and type of major health problems reported at the time of death or censoring. In this model, significant factors were age at diagnosis, sex, and either type of major health problem or number of health problems. Cats with renal disease or cancer were more likely not to survive and increasing from none to 2 health problems also decreased survival. Renal problems and cancer were the most common health problems at the time of death or censoring. This study provides estimates of duration of survival for cats successfully treated for hyperthyroidism with radioactive iodine, which can be useful in assisting with client treatment decisions.

Abstracts

Effect of dietary management on the survival of cats with chronic renal failure Elliott, J., Rawlings, J. M., Markwell, P. J. & Barber, P. J. (2000) Survival of cats with...

Survival of cats with naturally occurring chronic renal failure: effect of dietary management.

Fifty cats with naturally occurring stable chronic renal failure (CRF) were entered into a prospective study on the effect of feeding a veterinary diet restricted in phosphorus and protein with or without an intestinal phosphate binding agent on their survival from initial diagnosis. Twenty-nine cats accepted the veterinary diet, whereas compliance (due to limited intake by the cats or owner resistance to diet change) was not achieved in the remaining 21. At diagnosis, both groups of cats were matched in terms of age, bodyweight, plasma creatinine, phosphate, potassium and parathyroid hormone (PTH) concentrations, packed cell volume and urine specific gravity. Feeding the veterinary diet was associated with a reduction in plasma phosphate and urea concentrations and prevented the increase in plasma PTH concentrations seen in cats not receiving the diet. Cats fed the veterinary diet survived for longer when compared with those that were not (median survival times of 633 versus 264 days). These data suggest that feeding a diet specifically formulated to meet the needs of cats with CRF, together with phosphate binding drugs if required, controls hyperphosphataemia and secondary renal hyperparathyroidism, and is associated with an increased survival time.

Prognosis for presumed feline vaccine-associated sarcoma after excision: 61 cases (1986-1996).

To evaluate time to first recurrence (TFR) and overall survival in cats with presumed vaccine-associated sarcomas (VAS) treated with excision. Retrospective study. 61 cats with presumed VAS. Medical records of cats that received excision as the only initial treatment for presumed VAS were reviewed to evaluate prognosis. Overall survival curves and TFR were determined. Median TFR was 94 days. Median TFR for tumors treated with excision performed at a referral institution (274 days) was significantly longer than that for tumors excised by a referring veterinarian (66 days). Radical first excision yielded significantly longer median TFR (325 days) than did marginal first excision (79 days). Cats with tumors located on the limbs had longer median TFR (325 days) than cats with tumors located in other sites (66 days). Median overall survival time was 576 days. Significant differences in survival times between groups were not detected. Few cats (13.8%) receiving only surgical treatment had long-term (> 2 years) survival. Radical first excision of presumed VAS is essential for extended TFR. Current recommendations for vaccination of the distal portions of the extremities are appropriate, because this practice permits radical excision of tumors (amputation) that develop at vaccination sites; however, surgery alone is seldom curative.

A matched observational study of survival in cats with enucleation due to diffuse iris melanoma.

Although a small number of cases of feline diffuse iris melanoma have been documented to metastasize, the prognosis is not known. In this matched observational study, the survival time of 34 cats with enucleation due to histologically confirmed diffuse iris melanoma was recorded. These results are compared to the survival times of 83 age-matched control cats. Affected cats had enucleation between 2 and 10 years prior to the study. One group of control cats with eye disease had enucleation for either lymphoplasmacytic uveitis (27 cases), ocular trauma (seven cases), or endophthalmitis (four cases). In these control cats, enucleations were performed between 2 and 10 years prior to this study. Forty-five additional control cats presented for vaccination between 2 and 10 years prior to the study. The extent of diffuse iris melanoma at the time of enucleation in affected cats was graded according to the extent of involvement of ocular tissues and the invasiveness of the tumor. Affected cats have a significantly decreased survival compared with control cats and cats with extensive tumors at the time of enucleation have the lowest survival rates. Cats with tumors confined to the iris survive at the same rate as controls. These results suggests that early enucleation is important to avoid premature death, presumed to be due to cancer metastasis in cats with diffuse iris melanoma.

Prognosis factors for survival in cats after removal of a primary lung tumor: 21 cases (1979-1994).

To identify possible prognostic factors for survival time in cats with a primary lung tumor after surgical excision. Retrospective clinical study. 21 cats with histologically confirmed primary lung tumors removed surgically. Medical records for cats treated between 1979 and 1994 at 14 participating veterinary referral hospitals were reviewed. After surgical resection and recovery, 18 cats died from metastatic disease with a median survival time of 115 days (range, 13 to 1,526 days). Three cats were lost to follow-up at 119 days, 251 days, and 410 days after the surgical procedure. Contingency table analysis to determine if an association existed between clinical findings (breed, age, gender, body weight, clinical signs, duration of clinical signs, and radiographic findings) or histological features and survival time was performed. Only histological morphology of the primary lung tumor showed a significant association with survival time. Twelve cats with moderately differentiated tumors had a significantly longer survival time (median, 698 days; range, 19 to 1,526 days) than the nine cats with poorly differentiated tumors (median, 75 days; range, 13 to 634 days). Surgical resection of a solitary primary lung tumor in cats is indicated. A poor prognosis for long-term survival is warranted for those cats having a poorly differentiated primary lung tumor.

The localization and survival of cats in a Kerr medium

The evolution of a coherent state in a Kerr medium is known to result in the production of “Schrödinger cat” states of the electromagnetic field. Here we examine the influence of dissipation on these Schrödinger cats. Our emphasis is on the case where individual realizations represent quantum trajectories appropriate to evolution conditioned by records of heterodyne measurements. This results in a stochastic Schrödinger equation, known to produce localized Wigner functions from previous studies of superposition states in open environments. We discuss and illustrate the nature of the localization in a Kerr medium, which is affected by the very strong nonlinearities governing the problem.

Treatment of mandibular squamous cell carcinoma in cats by use of mandibulectomy and radiotherapy: Seven cases (1987-1989)

Summary Seven cats with squamous cell carcinoma involving the mandible were treated by surgery and radiotherapy. Surgery consisted of hemimandibulectomy or combined rostral and hemimandibulectomy, gastrostomy tube placement, and submandibular lymph node excisional biopsy. Radiotherapy (orthovoltage or 60Co) commenced 2 weeks after surgery. Histologically, the tumor invaded surgical margins in 6 of 7 cats. Nerve infiltration was histologically identified in 2 cats. All cats had stage-3 disease with radiographic evidence of mandibular bone involvement. Age ranged between 8 and 16 years (median, 10 years). Hypercalcemia (2), feline immunodeficiency virus (2), and hyperthyroidism (1), were detected in cats prior to treatment. Survival after surgery,) was a median of 14 months (range = 3 to 36 months, mean = 15 months). Six cats were euthanatized because of recurrence of disease at 3, 7, 9, 16, 21, and 36 months. One cat was euthanatized at 14 months because of an unrelated disease. Complications of tongue lagging, drooling after meals, mandibular drift, maxillary ulceration, and alopecia of the jaw developed in a few cats. Radiation at the primary site and regional lymph nodes after surgery of curative intent extended survival in cats with mandibular squamous cell carcinoma.

Risk factors, clinical signs, and survival in cats with a clinical diagnosis of idiopathic hypertrophic cardiomyopathy: 74 cases (1985-1989)

Summary Population characteristics, risk factors, and survival characteristics were evaluated in 74 cats with hypertrophic cardiomyopathy (hc) seen at North Carolina State University veterinary teaching hospital from 1985 to 1989, and compared with 82 clinically normal cats. The mean (± sd) age of cats with HC was 6.5 (4.0) years. Neutered males were at significantly greater risk (odds ratio 3.1) than neutered females. Breed, body weight, or coat color were not determined to be risk factors for hc. Tricolor cats were significantly underrepresented, probably reflecting the male predisposition for hc and not a true risk reduction associated with coat color. Forty-one cats were without clinical signs of heart disease (murmur and/or gallop sound only), 24 were in congestive heart failure, and 9 had systemic arterial embolism, 3 of which had concomitant congestive heart failure. The median survival time for 61 cats with HC, for which survival information could be obtained and that were not euthanatized on day 1, was 732 days. Survival was not affected by age at diagnosis, breed, body weight, or sex. However, clinical signs were important in determining prognosis; cats with heart rates < 200 beats/min survived significantly longer (median survival > 1,830 days) than those with heart rates ≥ 200 beats/min (median survival = 152 days). Cats without clinical signs (median survival > 1,830 days) survived longer than those with clinical signs, and cats in heart failure survived a median of 92 days, compared with 61 days for those with systemic arterial embolism. Analysis of survival revealed no significant difference between the 2 groups of cats with clinical signs; however, all cats with embolism and only 60% of cats with heart failure were dead 6 months after diagnosis.

Evidence for or Against the Efficacy of Calcium Channel Blockers for Management of Hypertrophic Cardiomyopathy in Cats

The positive lusitropic and direct coronary vasodilating properties of the calcium channel blocking agents are beneficial therapeutic effects not provided by the beta-adrenergic blocking agents for the management of feline HCM. Data from cats studied at the University of Tennessee suggest that diltiazem more consistently alleviates clinical signs and more effectively prolongs survival in cats with HCM than either propranolol or verapamil. Orally administered diltiazem appears to have sustained beneficial effects on left ventricular filling and cardiac performance based on its ability to reduce resting heart rate, decrease blood lactate concentration, increase venous oxygen tension, improve echocardiographic parameters, and resolve radiographic abnormalities. Long-term diltiazem administration may also reverse myocardial hypertrophy in some patients. There appear to be few if any side effects of this drug. Diltiazem, therefore, provides a safe and effective approach for the management of feline HCM.

Erythrocyte Pathology and Mechanisms of Heinz Body-mediated Hemolysis in Cats

Despite the frequency of both oxidant drug-induced and spontaneous Heinz body formation in cats, the cellular and biochemical mechanisms by which Heinz bodies result in red blood cell (RBC) destruction and hemolytic anemia in this species remain unknown. Feline spleens are non-sinusoidal and inefficient at removing Heinz body-containing RBC from the circulation; therefore, alternative mechanisms must be involved in accelerated RBC destruction. Propylene glycol (PG) ingestion causes dose-dependent Heinz body formation and decreased RBC survival in cats. We investigated several aspects of Heinz body-containing RBC from three cats ingesting diets that provided 8.0 g PG/kg body weight for up to 3 weeks, in order to characterize cellular lesions that are associated with the presence of Heinz bodies and that might contribute to chronic, accelerated RBC destruction, as well as to gain insight into the mechanism by which PG induces Heinz body formation. Erythrocytes with PG-induced Heinz bodies had decreased levels of reduced glutathione and adenosine triphosphate and reduced deformability. There was no change in hemoglobin isoelectric focusing or membrane lipid peroxidation. Electrophoretic patterns of Heinz body-containing RBC membranes were significantly altered, and membrane surface charge distribution was disturbed. Progressively protruding Heinz bodies suggested that extrusion of Heinz bodies may be a means of cell healing and/or destruction in the absence of splenic pitting. When compared to results obtained using RBC from cats treated with the oxidant drug phenylhydrazine, significant differences were noted in packed cell volume, turbidity index, membrane heme, and morphologic appearance of Heinz bodies. Our results indicate that multiple cellular abnormalities develop in RBC with PG-induced Heinz bodies that do not cause acute hemolysis but that may shorten RBC survival. Propylene glycol-induced Heinz bodies provide an ideal model for studying the chronic effects of Heinz bodies on RBC structure and function and may be useful in understanding the mechanisms of formation and the consequences of endogenous Heinz bodies in cats.

Dynorphin(1-13) improves survival in cats with focal cerebral ischaemia.

Since the discovery of opiate receptors in the central nervous system (CNS), it has become apparent that endogenous opiate ligands are involved in CNS function. Most attention has focused on their role in modulating pain, but they have also been implicated in various physiological functions and in disease states. We are concerned with evidence that endogenous opioid peptides may also contribute to the neurological deficits arising from cerebral ischaemia. Dynorphin, which is widely distributed in the brain and pituitary, has been reported to produce unusual motor and behavioural effects and may act as a regulatory neuropeptide, not as a classical opiate agonist or antagonist. We have therefore administered to cats in which the right middle cerebral artery had been occluded both dynorphin (1-13) and analogue and control materials. We find that dynorphin (1-13) prolongs survival.

Antibody response and virus survival in cats vaccinated against feline leukaemia.

WE have shown that leukaemia virus can be transmitted from cat to cat by contact or aerosol1. There is also substantial epizootiological evidence that such transmission occurs in natural conditions2,3. Horizontal transmission occurs because feline leukaemia virus (FeLV) replicates not only in cells of the haematopoietic system but is also found in large amounts in respiratory and alimentary mucous membranes and is excreted in the urine1. It is therefore not surprising that the infection in cats is fairly common. In the City of Glasgow we found that about one third of the cats sampled had antibodies against FeLV (mean titre = 2; ref. 4). We recently examined 100 young cats from the surrounding countryside and found antibody in six (mean titre = 20). These facts indicate that vaccination would be valuable and we have evidence that it is feasible. Here we report on the use of FeLV-infected cells to produce an immune response of a high level in cats.