Feline geriatrics: an overview (Proceedings)

The Effects of Aging on the Body

Immune System

• Aging causes decline in immune function and host defense

• Chronic geriatric diseases can impair immune function

• Decreased hydration - decreased immune function

• Decreased cough reflex - pulmonary defense

Blood

• No change in basal hematopoiesis with aging

• Ability to respond to increased demand changes

• Geriatric diseases can cause anemia

• Decreased blood flow due to dehydration or underlying disease

Skin

• Decreased elastin content of skin

o assessment of hydration is difficult

• Geriatric skin is thinner

• Less effective grooming in cats

o matting

o odor

o dermatitis

• Claws can be overgrown and brittle

Neurological Changes

• Central Nervous System

o Neurochemical alterations

o Memory loss

o Decline in intelligence

• Hearing

o Cochlear hair cells decline progressively from birth

o auditory chain arthritis

o chronic ear infection

o neurological degeneration

o owners are usually unaware

The Eye

• Lenticular sclerosis

o less pronounced in cats than in dogs

• Iris

o iris ciliary muscle atrophy are common

o significant?

• Retina

o detachments occur secondary to hypertension

Oral cavity

• Dental disease is extremely common

• Decrease in olfaction occurs in aging people

• Responsible for decreased food intake in non-sick geriatric animals?

• No change in temperature, viscosity, or gustation associated with aging in human beings

• Dental disease is rarely a cause of anorexia

Cardiopulmonary

• Heart

o no change in heart rate

o increased wall thickness, decreased relaxation

o increased sternal contact on radiographs

• Lungs

o decreased elasticity and tidal volume

o decreased expiratory reserve and cough reflex

o coughing is rare in cats

o not a common cause of morbidity in aged pets

• Gastrointestinal

o Decreased gastric and intestinal mucosa turnover

o Delayed colonic transit time/increased small intestinal transit

o Decreased absorption of water,minerals, electrolytes

o Increased absorption of fat-soluble vitamins?

o Gastrointestinal diseases more severe in geriatric patients

• Urinary System

o Kidney size and function decline in most species with aging

o Impaired potassium handling

o Renal pelvis calcification in cats

o Age is a risk factor for calcium-containing urinary stones in cats

Skeleton

• Decreased proteoglycan, tensile strength and collagen content of cartilage

• Decreased chondroitin sulfate, keratin sulfate, and hyaluronic acid production

• DJD is common but may be might be less noticeablein cats than in dogs

• Radiographic findings with aging

o calcified costochondral junctions

o spondylosis

Pharmacology of Aging

• Changes in Body composition = change in Vd

• Renal clearance decreases with aging

• Hepatic clearance decreases with aging

• Clearance altered by drugs and disease

• Drugs should be used with caution

• Start at low doses

• Escalate cautiously

• Attention to drug interactions

Common Disorders of Geriatric Cats

Dental Disease

• Most common geriatric disorder

• Rarely affects ability to eat

• Significant cause of discomfort & morbidity

• Age is not a reason to withhold treatment!

• Dental radiographs should be performed

• Preventative dental care important

Chronic Renal Failure - Diagnosis

• Renal function should be monitored in all geriatric cats

• Cats with CRF can have USG of 1.035

• Hypokalemia is common

• Proteinuria precedes isosthenuria/azotemia

• Isosthenuria predisposes to UTI

• Most common cause of death of old cats

• Probably due to chronic inflammation

• Clinical signs

o Excessive drinking and urinating

o Weight loss, poor appetite

o Vomiting

o Lethargy

• Diagnosis of Chronic Renal Failure

o Urinalysis is most important

o Unable to concentrate urine

o Blood Tests

• Anemia and azotemia, sometimes electrolyte problems

o Urine Culture

• Infection of the kidney is possible

o Blood Pressure

o Ultrasound

• Chronic Renal Failure - Treatments

o Phosphorus-/protein-restricted diets

o Oral Potassium (1-2 mEq/kg/day)

o Fluid therapy

o Antihypertensive drugs

o amlodipine or enalapril

o Erythropoietin

o Phosphate binders

o H2 Blockers

• Chronic Renal Failure - Monitoring

o Dehydration

o Hypertension

o Anemia

o Hypokalemia

o Azotemia

o Proteinuria/pyuria

o Hyperphosphatemia

o Acidemia

Feline Hyperthyroidism

• Historical Findings

o Weight Loss 88%

o Hyperactivity 31%

o Polyphagia 49%

o PU/PD 36%

o Vomiting 44%

o Diarrhea 15%

o Decreased Appetite 16%

o Large fecal volume 8%

o Anorexia 7%

• Physical Findings

o Goiter 83%

o Thin 65%

o Heart murmur 54%

o Tachycardia 42%

o Gallop 15%

o Aggression 15%

o Unkempt 9%

o Thick claws 6%

• Diagnosis

o Serum TT4 is initial screening test of choice

o Some cats have "occult hyperthyroidism"

• Treatments

o Drugs, Surgery, or Radioiodine

o Is there a treatment of choice?

o Treatment causes a decline in GFR

o Caution in cats with renal disease

o Methimazole for cats with renal disease

Cancer

• Skin

o Common in dogs, not in cats

o Vaccine-associated fibrosarcoma in cats

• Mammary gland

o 50% are malignant in dogs, and 85% in cats

o Prevented by spaying at 6 – 12 months

• Mouth

o Oral Squamous Cell in cats

• Abdominal

• Lymphoma

Diabetes Mellitus

• Persistent hyperglycemia and glycosuria

• Increased risk with obesity, especially in cats

• Appetite, activity and water consumption are the best indicators of glycemic control

• Treatment of choice is insulin, although oral medications are available.

• Clinical Features

o Physical exam may be normal

o Obesity may be seen

o Weight loss may be noted

o Diabetic neuropathy

o Obesity

Designing Wellness Programs for Geriatric Cats

Client Communication is the most important aspect.

• Old age is not a disease

• Goal is to identify and treat diseases early in order to extend life and enhance quality

• Maintenance of body condition

Health Monitoring

• Monthly Checklists

o Helps clients monitor changes at home

• Frequent Office Visits

o Healthy geriatrics at least every 6 months

o Sick geriatrics more often

AAFP Vaccination Guidelines

• FVRCP every 3 years

Healthy Cats

• History and physical exam every 6 months

• Body weight and condition score every 6 months

• Annual screening tests

• Complete blood count

• Creatinine, Potassium, TT4,Urinalysis,FeLV/FIV testing if at risk

• Blood pressure measurement

Sick Cats

• History and physical exam frequently, body weight and condition score at every visit

• Screening tests (frequency determined by cat's disease and condition)