Download Chapter 25

Energy- & Protein-Modified Diets
for Cancer & HIV Infection
Chapter 25
Nutrition & Diet Therapy, 7th edition
I. Cancer
Malignant: cancerous
cell or tumor which
can injure healthy
tissue & spread cancer
to other parts of the
body
• Growth of malignant tissue
• Many different kinds of malignant
growth
–
–
–
–
Differ in characteristics
Occur in different locations in the body
Take different courses
Require different treatments
• Advanced cancers, especially those
of GI tract, can seriously impair
nutrition status
Nutrition & Diet Therapy, 7th edition
Cancer
• Cancer development (carcinogenesis)
– Arises from mutations in genes that control cell
division
– Abnormal mass of cells (tumor) develops own
blood supply to deliver oxygen & nutrients, &
otherwise support tumor growth
– Tumor causes disruption of functioning of
surrounding tissues
– May spread to another region of body
(metastasis)
– Reasons for development varied, including
exposure to cancer-causing agents
(carcinogens) in environment
Nutrition & Diet Therapy, 7th edition
Nutrition & Diet Therapy, 7th edition
Cancer
• Nutrition & cancer risk
– Diet, lifestyle, and environmental
factors have strong influence on cancer
risk
• Damage to DNA
• Alteration of metabolism of carcinogens
• Inhibition of formation of carcinogens
Nutrition & Diet Therapy, 7th edition
Nutrition & Diet Therapy, 7th edition
Nutrition & Diet Therapy, 7th edition
Cancer
Frequent consequences
• Consequences of
cancer
– Depends on location of
tumor, severity &
treatment
– Complications often due
to tumor’s effect on
surrounding tissues
– Effectiveness of
treatment is greatest
with early detection &
intervention
Nutrition & Diet Therapy, 7th edition
– Cancer cachexia: wasting
syndrome characterized
by anorexia, muscle
wasting, weight loss &
fatigue
– Metabolic changes
– Anorexia & reduced food
intake related to…
• Chronic nausea & early
satiety
• Fatigue
• Pain
• Mental stress
• Effects of cancer txmeds, chemo, etc.
• Obstructions
Cancer
• Treatments for cancer
– Main goals of treatment are to remove cancer cells,
prevent further tumor growth & alleviate symptoms
– Primary treatment involves surgery, chemotherapy,
radiation therapy, or combination of the three
– Surgery
• Purpose
– Tumor removal
– Determination of extent of involvement
– Discern involvement of surrounding tissues
• Acute metabolic stress caused by surgery increases energy
& protein needs; may increase muscle wasting
• Other effects can reduce food intake, contributing to
nutrient losses & malnutrition
Nutrition & Diet Therapy, 7th edition
Cancer
• Treatments for cancer (con’t)
– Chemotherapy
• Relies on use of drugs to inhibit tumor growth
• Most drugs are toxic to healthy cells as well as cancerous ones
• Associated with variety of nutrition-related side effects
– Radiation therapy
• Treatment of cancer cells by damaging DNA (& causing cell death)
with x-rays, gamma rays, other atomic particles
• Focused directly on tumors with minimal damage to surrounding
tissues
• See p. 679, T 25-5, for specific nutr. effects of chemo & radiation
– Bone marrow transplant
• Replacement of bone marrow that has been destroyed by
chemotherapy or radiation therapy
• Used as one of primary treatments for leukemia
• Immunosuppressant drugs necessary when separate donor used
• Major impact on food intake & nutrition status
Nutrition & Diet Therapy, 7th edition
Cancer
• Nutrition therapy for cancer
– Goals of nutrition therapy
• Minimize loss of weight & muscle tissue
• Correct nutrient deficiencies
• Provide diet that can be tolerated & enjoyed despite
complications of disease
– Nutrition needs among cancer patients vary
widely
– Appropriate nutrition helps patients preserve
strength & improve recovery
– Initial screening & follow-up assessment for
malnutrition is necessary during treatment &
recovery periods-p.690
Nutrition & Diet Therapy, 7th edition
Cancer
• Nutrition therapy for cancer (con’t)
– Protein & energy intake recommendations
• Recommended ranges vary depending on patient
condition
• Energy needs may be 25-35 kcalories/kg, depending
on patient’s current weight, activity level, degree of
metabolic stress, energy needs for tissue repair &
weight regain
• Protein requirements depend on level of metabolic
stress, treatment stage & cachexia-p.680
• Regular monitoring of weight changes, nutrition
status & adjustments of diet necessary
• Supplementation may be necessary or How To-p.681
Nutrition & Diet Therapy, 7th edition
Cancer
• Nutrition therapy for cancer (con’t)
– Managing symptoms & complications
• Thorough nutritional assessment
• Patient’s response to strategies varies
considerably
– Enteral & parenteral nutrition support
• Necessary for patients with long-term or
permanent GI impairment or severe
complications interfering with food intake
• Enteral nutrition preferred unless
contraindicated
Nutrition & Diet Therapy, 7th edition
II. HIV Infection
• Human immunodeficiency (HIV) virus
attacks immune system, disabling
defenses against infection & some
cancers
• Often leads to acquired immune
deficiency syndrome (AIDS)
• Diagnosis devastating to patient
– Can expect ever-worsening course of illness,
possibly death
– Recent treatment options have expanded,
offering benefits to patients & improvements
in quality of life
Nutrition & Diet Therapy, 7th edition
HIV Infection
• World-wide epidemic
– Although no cure,
progress in treatment has
been made
– Best course of treatment
is prevention
– Death rate in U.S. begin to
decline during 1990s
– Progression from HIV to
AIDS has also slowed
• Transmission
– Sexual transmission
– Direct contact with
contaminated body fluids,
including blood, semen,
vaginal secretions, breast
milk
Nutrition & Diet Therapy, 7th edition
• Risk factors
– Many individuals remain
asymptomatic during early
stages—unknowingly
passing infection to others
– Individuals at risk should
be tested (T. 25-8)
– Testing can detect HIV
antibodies within several
months after exposure,
sometimes sooner (1-2
wks.)
– Estimated 25% of infected
individuals in U.S. are
unaware of infection
Nutrition & Diet Therapy, 7th edition
HIV Infection
• Consequences of HIV
Infection
– Destruction of immune cells—
most affected are helper T cells
– Nonspecific early symptoms
• Fever, sore throat, malaise, skin
rashes, nausea, muscle & joint
pain, diarrhea
• After initial symptoms, may
remain asymptomatic for 5-10
years or more
• Untreated, depletion of T cells
eventually increases
susceptibility to opportunistic
infections
Nutrition & Diet Therapy, 7th edition
Opportunistic Infection
Infection that results from
microorganisms that do
not cause disease in
healthy individuals, but
are damaging to those
with compromised
immune system (exs.
Thrush, pnuemonia, TB)
HIV Infection
• Consequences of HIV Infection (con’t)
– AIDS-defining illnesses
• Diseases and complications associated with later stages of HIV
infection, including…
– Severe infections
– Certain cancers
– Wasting of lean tissue
• Disease progression monitored by measuring concentrations of
helper T cells, circulating virus & monitoring clinical symptoms
– HIV-lipodystrophy syndrome
• Collection of abnormalities in fat & glucose metabolism resulting
from HIV drug treatment
• Includes body fat redistribution, abnormal blood lipid levels &
insulin resistance, breast enlargement (in men & women), fat
accumulation at base of neck, lipomas
• Often develop hypertriglyceridemia, low HDL cholesterol levels,
glucose intolerance & hyperinsulinemia
Nutrition & Diet Therapy, 7th edition
HIV Infection
• Consequences of HIV Infection
(con’t)
– Weight loss & wasting (AIDSrelated wasting syndrome)
• 10% weight loss within 6
months
• Diarrhea or fever for more than
30 days with no known cause
• Linked to disease progression,
reduced strength & fatigue
• Severe in later stages;
increases risk of death
• Causes
– Anorexia & reduced food
intake
– Altered metabolism &
malabsorption
– Chronic diarrhea
– Diet-drug interactions
Nutrition & Diet Therapy, 7th edition
Anorexia & reduced food
intake
• Key factor in
development of wasting
• Results from many
associated problems
– Emotional distress, pain
& fatigue
– Oral infections
– Respiratory disorders
– Cancer
– Medications
HIV Infection
• Consequences of HIV Infection (con’t)
– GI tract complications
• May result from opportunistic infections, medications
or HIV infection itself
• High risk of malnutrition related to…
– Infections in stomach & intestines (villi short & flat)
– Nausea, vomiting & diarrhea from medications
– Bacterial overgrowth resulting from antiviral, antibiotic
& antifungal medications
• Treatment
– No cure, but treatment can slow progression,
reduce complications & alleviate pain
Nutrition & Diet Therapy, 7th edition
HIV Infection
• Treatment
– Highly active antiretroviral therapy (HAART)
• Combination of 3 or more antiretroviral agents
• Improved lifespan & quality of life for many patients
• Multiple adverse effects from drugs
–
–
–
–
–
–
–
–
GI effects; diet-drug interactions
Skin rashes
Headache
Anemia
Tingling & numbness
Hepatitis
Pancreatitis
Kidney stones
Nutrition & Diet Therapy, 7th edition
HIV Infection
• Treatment (con’t)
– Control of anorexia &
wasting
• Appetite stimulants
• Physical activity
• Anabolic hormones (HGH)
– Control of lipodystrophy
• Under investigation
• Aerobic activity &
resistance training help
reduce abdominal fat
• Alternative antiretroviral
drugs to alleviate
symptoms
• Medication treatment for
abnormal blood lipids &
insulin resistance
Nutrition & Diet Therapy, 7th edition
– Alternative therapies
• May be unconventional
• Many harmless, but
can be expensive
• Monitoring use of
dietary supplements is
essential to reduce risk
of nutrient-drug &
herb-drug interactions
HIV Infection
• Medical nutrition therapy
– Initial nutrition assessment to provide baseline
– Weight maintenance
• Primary objective: maintain weight & muscle tissue
• Determine dietary & lifestyle factors that may
interfere with food intake, appetite & physical activity
• Provide suggestions to prevent future weight
problems
• Small, frequent feedings may be better tolerated
than large meals
• Addition of nutrient-dense food and snacks, protein
or energy bars, oral supplements may help
Nutrition & Diet Therapy, 7th edition
HIV Infection
• Medical nutrition therapy (con’t)
– Vitamins & minerals
• Needs are variable
• Multivitamin-mineral supplements often recommended to
reduce risk of deficiencies associated with reduced food
intake, malabsorption, diet-drug interactions & nutrient
losses
– Metabolic complications
• Dietary adjustments for treatment of insulin resistance &
elevated triglyceride & LDL levels should be tried before
medication treatment
– Achieve & maintain desirable weight
– Replace saturated fats with monounsaturated &
polyunsaturated fats
– Limit intake of trans fats & cholesterol
– Replace sugar intake with complex carbohydrates
• Maintain regular physical activity
Nutrition & Diet Therapy, 7th edition
HIV Infection
• Medical nutrition therapy (con’t)
– Symptom management
– Food safety-use safe handling and food
preparation (HIV h risk of infections)
– Enteral & parenteral nutrition support
• Patients may need aggressive nutrition
support during later stages
• Tube feeding preferred if GI tract is
functional
• Parenteral nutrition reserved for patients
who cannot tolerate enteral nutrition
Nutrition & Diet Therapy, 7th edition
Nutrition in Practice—Ethical
Issues in Nutrition Care
• New technologies, including availability
of specialized nutrition support, results
in difficult ethical dilemmas
• When medical treatments prolong life
by delaying death, reduced quality of
life may result
• Decisions to withhold or withdraw
nutrition support require careful
consideration of ethical principles
Nutrition & Diet Therapy, 7th edition
Nutrition in Practice—Ethical
Issues in Nutrition Care
• Life-sustaining procedures
–
–
–
–
–
Nutrition support & hydration
CPR
Defibrillation
Mechanical ventilation
Dialysis
• Patient’s rights to treatment
– Difficult to determine best course of action for terminally
ill or patients who are unlikely to regain consciousness
– When patients (or caregivers) demand treatment (when
health practioners consider it to be futile), legal
resolution may follow
Nutrition & Diet Therapy, 7th edition
Nutrition in Practice—Ethical
Issues in Nutrition Care
• Advance directive
– Living will or medical directive: include detailed
instructions regarding life-sustaining procedures
individual wants or does not want
– Take effect when it is determined that the patient lacks
ability to understand & make treatment decisions
• Durable power of attorney (or health care proxy)
– Another person, or health care agent, is appointed to act
as decision-maker in event of patient incapacitation
– Agent is given comprehensive power to supervise care,
make decisions about medical staff, facility & procedures
Nutrition & Diet Therapy, 7th edition