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Chapter 35 • Vision Loss 431
https://t.me/med1917
Myopia (nearsightedness) is when the cornea and
lens of the eye focus the image in front of the retina.
Hyperopia (farsightedness) is a refractive error in which
the focus of an image is behind the retina. Hyperopia
can be corrected to some degree by adjustment of the
natural lens (accommodation) normally done for nearfocusing. The use of accommodation can cause visual
fatigue, discomfort, and headache.
Astigmatism
Astigmatism is an irregularity in the refractive system
of the eye that prevents light from being focused onto
the retina. It can be secondary to the shape of the cornea or lens and is usually correctable with lenses.
Cataracts
A cataract is any opacity of the crystalline lens of the
eye. There are many causes of cataracts, and they can
be dened by onset, cause, or anatomy.
Congenital cataracts are inherited in an autosomal
dominant form and are associated with intrauterine
infections by the TORCH complex of organisms.
Cataracts of infancy and childhood occur in 1 per
1000 live births, and congenital glaucoma occurs in
1 per 10,000 live births.
Adult cataracts are a major cause of visual impairment in the elderly because with time, the human lens
begins to develop opacities. Cataracts can be caused by
galactosemia, metabolic disorders (e.g., diabetic cataracts), and trauma (e.g., from heat or blunt trauma);
steroid-induced cataract formation is also possible. The
rst signs of opacity are the inability to focus on near
objects (presbyopia) and altered color vision.
Optic Neuritis
Optic neuritis occurs more often in younger adults, 20
to 50 years old, and in women; it is typically monocular. It is often idiopathic and may be associated with
multiple sclerosis, post viral infection, and granulomatous inammatory conditions. Vision loss occurs over
a few hours to days and is extremely variable. Visual
eld loss includes central scotoma in 90% of patients.
In the majority of patients, pain precedes the vision
loss and is worse with eye movement.
Optic Nerve Hypoplasia
This visual disorder affects the optic nerve, the bundle
of bers that transmits signals from the retina to the
brain. It is a nonprogressive disorder in which the optic
nerve is 25% smaller than the normal size. Some children have a loss of peripheral vision while others lose
central vision.
Injury
More than 100,000 eye injuries occur annually in the
general population, of which 90% are preventable with
the use of protective eyewear. Exposure to long periods
of high heat or blunt trauma to the eye globe can result
in cataracts.
Retinoblastoma
This is the most common intraocular tumor of childhood; it occurs bilaterally in 30% of cases. A common
symptom is strabismus. Retinoblastoma is inherited in
an autosomal dominant manner. Early lesions are at,
transparent, or white masses in the retina. The tumor
can spread to the brain through the optic nerve or into
the bone marrow.
Retinopathy of Prematurity
This condition is seen in premature infants and refers
to the changes of ischemia, blood vessel growth, and
brosis that occur because of inadequate oxygen
delivery to the peripheral retina. The vessels of
the retina normally complete vascularization by
40 weeks of gestation. Infants who are born before
this time may have incomplete vascularization with
subsequent poor vessel development and visual impairments. Infants smaller than 1500 grams (g) are at
greatest risk.
Central Retinal Artery Occlusion
Patients with this condition have a sudden onset
of severe vision loss in one eye. There is no associated
pain. The loss is caused by plaque lodging at the level
of the lamina cribrosa. On physical examination a few
hours after occlusion, the retina becomes edematous
and white or opaque. There is a reddish-orange reex
from the intact choroidal vascular and foveola that
creates a “cherry red spot” that contrasts with the surrounding white retina. With time, the retinal artery
opens and the retinal edema clears.
Glaucoma
Glaucoma is loss of vision because of increased pressure in the eye; it is characterized by defects in the
visual eld and optic nerve damage. It is the second
leading cause of blindness in the United States. The
432 Chapter 35 • Vision Loss
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condition is painless, and symptoms appear in late
stages. Ophthalmic examination reveals pathological
cupping of the optic disc that may be asymmetrical.
Patients with intraocular pressures above 21 mm Hg
should be referred to an ophthalmologist (Box 35-2).
Retinal Detachment
This condition occurs when the neurosensory retina is
separated from the retinal pigment epithelium. About
half of patients will have brief ashes of light (photopsia)
or oaters (entopsia). It is caused by a collection of uid
beneath the neurosensory retina, traction from brovascular elements associated with diabetic retinopathy, or
trauma. Nearly 95% of detachments are treatable.
Macular Degeneration
Age-related macular degeneration is the leading cause of
blindness in the United States. It may be asymptomatic
or associated with gradual loss of central vision. Risk
factors include advanced age, family history, cigarette
smoking, hyperopia, and hypertension. There are two
forms of pathological macular degeneration. The exudative form results in rapid vision loss caused by the development of a subretinal pigment epithelial neovascular
membrane. The nonexudative form is associated with
gradual loss of central vision. Distortion upon testing
with the Amsler grid is found in macular degeneration.
Diabetic Retinopathy
Diabetic retinopathy is a retinovascular disease that
occurs in two forms. Nonproliferative retinopathy is
characterized by microaneurysms, macular edema,
lipid exudates, and intraretinal hemorrhages. In proliferative retinopathy, blood vessels regenerate on the
retina. The patient may be asymptomatic or have decreased vision or oaters. Diabetic retinopathy progresses with the duration of diabetes.
Box 35-2
Adult Vision Screening
Uveitis
Uveitis is a general term used to describe inammatory
activity of the iris, ciliary body, and choroid. Symptoms vary according to cause and severity, but most
patients experience some decrease in vision, light sensitivity, and tearing. Pain may be variable. Acute uveitis lasts less than 3 months, but the condition may
have a chronic recurrent pattern.
Optic Nerve Glioma
Optic nerve gliomas are present in two forms. In the
adult, they are malignant glioblastomas; in the child,
they are benign pilocytic astrocytomas. They appear
in children younger than age 10 and are highly
associated with neurobromatosis, a condition associated with café au lait lesions of the skin. In children, gliomas may appear as the rapid onset of vision
loss with headache. Of the malignant optic nerve
gliomas, nearly 75% present with unilateral, rapidly
progressive vision loss with pain.
Craniopharyngioma
Craniopharyngiomas are tumors that arise from squamous epithelial cells of the brain. They are most
common in the rst two decades of life but also
may occur in adults 50 to 70 years old. Children’s
presenting symptoms include headache and visual
disturbance caused by increased intracranial pressure. Nystagmus and bitemporal hemianopsia are
pathognomonic for this tumor. In the older patient,
visual decit is common in the presence of normal
optic discs.
Chemical or Thermal Trauma
A chemical burn is an ophthalmic emergency. Alkaline
solutions denature eye proteins and lyse cell membranes, allowing the chemical to penetrate the eye.
Acid burns can also cause severe damage, but the acid
solution precipitates proteins, decreasing the amount
of penetration damage.
Visual acuity should be assessed intermittently after
age 40 with no optimal interval recommended. Routine
screening for glaucoma by primary care providers is not
recommended.
Congenital Infection
Congenital TORCH infections can cause vision problems in infants. Postnatal screening is performed to
diagnose a TORCH infection.
Chapter 35 • Vision Loss 433
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DIFFERENTIAL DIAGNOSIS OF Common Causes of Vision Loss
CONDITION HISTORY PHYSICAL FINDINGS DIAGNOSTIC STUDIES
Strabismus Family reports child’s eyes
cross, family history
Amblyopia May have history of premature
birth, Down syndrome, cere-
Refractive errors Sitting close to television,
Cataracts Blurred vision, glare, distortion
Optic
neuritis
Optic nerve
hypoplasia
Injury, penetrating
injury
Retinoblastoma Family history, child 2 years old
Nystagmus History of eyes moving repeti-
Retinopathy of
prematurity
Central retinal
artery occlusion
Glaucoma Most often painless, gradual
Retinal detachment Sensation of flashing light
Macular
degeneration
Diabetic
retinopathy
Uveitis History of infection or chronic
bral palsy, hydrocephalus
squinting
and change in color
perception, increased age,
history of infection, trauma, or
chronic disease
History of multiple sclerosis, viral
infection, pain with eye movement, rapid vision loss
History of vision loss, may have
central vision but no peripheral
vision
History suggesting head or eye
trauma (blunt or sharp)
or younger
tively, searching
Premature birth ,36 weeks,
1500 g, oxygen administered,
may be a twin
Sudden onset of painless vision
loss, may come and go
vision loss, blurring, and halos;
more common in older adults;
history of systemic disease
accompanied by shower of
floaters; history of trauma to
head or face
Older than 60 years, decreased
central vision, blue eyes,
image larger in one eye
History of diabetes, floaters,
gradual vision loss
inflammation, mild to moderate
pain, photophobia, tearing
Extraocular movements
abnormal, cover/uncover
test positive
Vision decreased in one eye Refer
Loss of visual acuity Screen with Snellen,
Whitish appearance of pupil,
bilateral or unilateral
Decreased visual acuity,
reduced color perception,
afferent pupil defect and
central scotoma
Optic nerve is one half to one
third normal size, pale to
gray in color, surrounded by
yellow halo
Directed by history Refer because of high
Partial or absent red reflex,
strabismus
Rhythmic, repetitive oscillation
of eyes
Abnormalities of retinal
vessels
Macular edema, cherry red
spot; may see vessel
narrowing
Decreased visual acuity; may
have increased intraocular
pressure on palpation of eye
globe
Retina markedly elevated;
appears gray with dark
blood vessels; may lie in
folds
Hyaline (drusen) deposits on
retina near macula, graygreen areas of pigment
under retina, decreased
visual acuity
Venous dilation, retinal
hemorrhages
Findings vary according to
cause and severity
Refer
Tumbling E, or figures;
refer
Refer
Refer
Refer
incidence of
penetrating injury
Refer
Refer
Refer
Refer
Refer for tonometry
Refer
Amsler grid
Refer
Refer
Continued
434 Chapter 35 • Vision Loss
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DIFFERENTIAL DIAGNOSIS OF Common Causes of Vision Loss—cont’d
CONDITION HISTORY PHYSICAL FINDINGS DIAGNOSTIC STUDIES
Optic nerve glioma Dimness of vision with loss of
fields; may be unilateral rapid
vision loss with pain
Craniopharyngioma Unilateral vision loss, headache,
child or adult
Chemical burn History of acid or alkaline
exposure
Thermal burns History of exposure to high heat,
occupational risk
Congenital
infections
TORCH, toxoplasmosis, rubella, cytomegalovirus, and herpes simplex.
TORCH, maternal exposure to
measles
Visual field defects, optic
atrophy
Funduscopic examination may
be normal
Treat first, then examine Immediate eye irrigation
Corneal opacities Refer
Retinitis, optic nerve hypo-
plasia
Refer
Refer
and referral
Screen for TORCH, refer
REFERENCES AND READINGS
Anonymous: Glaucoma: early detection can minimize vision loss,
Mayo Clin Health Lett 23:7, 2005.
Coles WH: Ophthalmology: a diagnostic text, Baltimore, Md, 1989,
Williams & Wilkins.
Harvey PT: Common eye diseases of elderly people: identifying and
treating causes of vision loss, Gerontology 49:1, 2003.
McPhee SJ, Papadakis MA: Current medical diagnosis and treatment,
ed 49, New York, 2010, McGraw-Hill.
Norton I: Practical ophthalmology—a survival guide for doctors and
optometrists, Emerg Med Australia 17:5, 2005.
Quillen DA: Common causes of vision loss in elderly patients, Am
Fam Physician 60:99, 1999.
Thompson L, Kauffman L: The visually impaired child, Pediatr Clin
North Am 50:225, 2003.
Tingley DV: Vision screening essentials: screening today for eye
disorders in the pediatric patient, Pediatr Rev 28:54, 2007.
World Health Organization: Visual impairment and blindness, Fact
Sheet 282, May 2009. Available online at http://www.who.int/
mediacentre/factsheets/fs282/en/print.html. Accessed June 23,
2010.
C H A P T E R
https://t.me/med1917
36
Weight Loss/Gain (Unintentional)
nintentional weight loss is a decrease in body
weight that is not voluntary. Weight loss in the
U
5% of usual body weight over a 6 to 12 month period.
Weight loss in the newborn may occur immediately
after birth but weight should begin to increase by
2 weeks of age. Weight loss will occur with reduced
energy (food) intake and increased metabolism or energy output. Every day individuals adjust energy balance to maintain a healthy weight through healthy eating and regular physical activity. Malignancy and
endocrine disorders are at the top of the list of causes of
unintentional weight loss, followed by gastrointestinal,
cognitive, behavioral, and functional disorders, as well
as age-related changes.
body requirements, causing the body to store fat.
Most adults do not intentionally gain weight, but
as we age, a decrease in physical abilities leads to a
decrease in metabolic rate (amount of energy used in
a given period), which in turn contributes to weight
gain. Unexplained weight gain may be more difcult
to identify, especially in the U.S., where the prevalence of obesity is 32.2% among adult men and
35.5% among adult women. The prevalence of childhood obesity is increasing. Unexplained weight gain
may be endocrine-related, age-related, or associated
with cognitive impairments.
adult is clinically signicant when it exceeds
Weight gain occurs when caloric intake exceeds
n How is your appetite?
n Can you describe your typical diet and activity
patterns?
n If an infant: If breastfeeding, how is breastfeeding
going?
n If an infant: If feeding formula, what kind is it and
how do you prepare it?
Measuring Weight
Individuals might note that their clothes are too loose
or too tight. Weight is usually measured by asking
the patient to step on a balance or electric scale
clothed and without shoes. Height is measured by
asking the patient to stand with the back against a
wall with heels touching the wall. There are several
ways to classify and measure body weight, but the
most commonly used method is the body mass index
(BMI) formula, which is BMI 5 weight (kg)/height
(m2) (see Appendix C). To enhance the reliability of
measurement of weight changes, ask the patient to
weigh himself or herself at the same time each day
using the same scale.
Weight and height in infants and children is measured by a scale and plotted on a National Center for
Health Statistics growth chart. Infants and children
should be measured in a supine position until the age
of 2 years. Head circumference is also measured and
plotted.
DIAGNOSTIC REASONING:
FOCUSED HISTORY
Unexplained Weight Loss
Has the patient lost weight? Is the weight
loss really unexplained?
Key Questions
n How do you know that you (or the child) have lost
weight?
n How old are you?
Age
Aging can be associated with both weight loss and
weight gain. Normally with aging there is less lean
muscle tissue, fat is deposited in the trunk and less in
the limbs, and metabolism slows. In the elderly it is
especially important to assess what medications are
being taken that could suppress appetite, cognitive
status, and memory. Functional limitations that may
impact nutrition include the ability to chew and swallow, prepare meals, and shop for food. Social isolation
can also contribute to eating less.
435
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Appetite
Appetite can be suppressed due to the presence of acute
or chronic illness. Cachexia will result from inadequate
energy intake and pathologic wasting of muscle or fat
tissue. The key symptom in cachexia is anorexia, or loss
of appetite. Psychosocial factors, such as anxiety or
depression, can contribute to a loss of appetite or lifestyle habits that include skipping meals or eating foods
of poor nutritional value.
Eating Habits/Nutritional Adequacy
and Physical Activity
Weight maintenance is a balance of energy expended
and energy consumed. General healthy dietary guidelines can be found in the Dietary Guidelines for
Americans (Box 36-1) and on MyPyramid (http://
mypyramid.gov). Daily caloric needs vary by age,
gender, pregnancy, and level of physical activity.
Athletes in training may underestimate their caloric
needs (Box 36-2).
Excess intake of fruit juices may decrease a child’s
appetite and cause weight loss. Conversely, excess
intake of fruit juices with high caloric content may
cause weight gain.
Breastfeeding
Observing and discussing issues regarding breastfeeding with the mother may reveal important information. Infants should be breastfed 8 to 12 times in a
24-hour period. Breastfeeding requires more energy
expenditure from the infant, and occasionally infants
fall asleep while feeding and thus do not receive
an adequate amount of breast milk. Nipple soreness is
usually caused by improper positioning and/or poor
latching or unlatching and can lead to a diminished
milk supply. Maternal hydration is important for
adequate milk supply.
Formula-Fed Infant
Investigating what formula the infant is being fed
and how the formula is prepared is important. Formulas come in powder and liquid forms. Powder
formula requires reconstitution with water. Liquid
formula comes in two forms: concentrated (requiring
the addition of water) and ready-to-feed. Taking a
history of how the formula is prepared is important
to determine whether incorrect preparation is causing
weight loss.
Are emotional issues contributing
to weight loss?
Key Questions
n Have you recently had a stressful event in your life?
How are you coping?
n Do you or anyone in your family have a problem
with anxiety or depression?
n How are you doing in school or at work?
n If a child: Is the child gaining weight appropriately?
Psychosocial Factors
Emotions have a big impact on appetite and eating
behavior. One reaction to extreme stress or depression may be a loss of appetite. Individuals may have
Box 36-1
• To maintain body weight in a healthy range, balance calories from foods and beverages with calories expended.
• To prevent gradual weight gain over time, make small decreases in food and beverage calories and increase physical
activity.
Key Recommendations for Specific Population Groups
• Those who need to lose weight. Aim for a slow, steady weight loss by decreasing calorie intake while maintaining an
adequate nutrient intake and increasing physical activity.
• Overweight children. Reduce the rate of body weight gain while allowing growth and development. Consult a healthcare
provider before placing a child on a weight-reduction diet.
• Pregnant women. Ensure appropriate weight gain as specified by a healthcare provider.
• Breastfeeding women. Moderate weight reduction is safe and does not compromise weight gain of the nursing infant.
• Overweight adults and overweight children with chronic diseases and/or on medication. Consult a healthcare provider
about weight loss strategies prior to starting a weight-reduction program to ensure appropriate management of other
health conditions.
From U.S. Department of Health and Human Services, U.S. Department of Agriculture: Dietary guidelines for Americans, 2005. Available online at
www.healthierus.gov/dietaryguidelines. Accessed August 5, 2010.
Key Recommendations for Maintaining A Healthy Weight
Chapter 36 • Weight Loss/Gain (Unintentional) 437
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Box 36-2
Engage in regular physical activity and reduce sedentary activities to promote health, psychological well being, and a healthy
body weight.
• To reduce the risk of chronic disease in adulthood: Engage in at least 30 minutes of moderate-intensity physical activity,
above usual activity, at work or home on most days of the week.
• For most people, greater health benefits can be obtained by engaging in physical activity of more vigorous intensity or
longer duration.
• To help manage body weight and prevent gradual, unhealthy body weight gain in adulthood: Engage in approximately
60 minutes of moderate- to vigorous-intensity activity on most days of the week while not exceeding caloric intake
requirements.
• To sustain weight loss in adulthood: Participate in at least 60 to 90 minutes of daily moderate-intensity physical activity
while not exceeding caloric intake requirements. Some people may need to consult with a healthcare provider before
participating in this level of activity.
Achieve physical fitness by including cardiovascular conditioning, stretching exercises for flexibility, and resistance
exercises or calisthenics for muscle strength and endurance.
Key Recommendations for Specific Population Groups
• Children and adolescents. Engage in at least 60 minutes of physical activity on most, preferably all, days of the week.
• Pregnant women. In the absence of medical or obstetric complications, incorporate 30 minutes or more of moderate-
intensity physical activity on most, if not all, days of the week. Avoid activities with a high risk of falling or abdominal trauma.
• Breastfeeding women. Be aware that neither acute nor regular exercise adversely affects the mother’s ability to successfully breastfeed.
• Older adults. Participate in regular physical activity to reduce functional declines associated with aging and to achieve
the other benefits of physical activity identified for all adults.
From U.S. Department of Health and Human Services, U.S. Department of Agriculture: Dietary guidelines for Americans, 2005. Available online at
www.healthierus.gov/dietaryguidelines. Accessed August 5, 2010.
Key Recommendations for Physical Activity
patterns of coping with stress by controlling food intake. Anorexia nervosa and bulimia are eating disorders most often diagnosed in young females. With
these two disorders, despite the low or normal weight,
the individual perceives herself or himself as overweight. Anorexia nervosa carries a high risk of complications due to electrolyte imbalances.
Failure To Thrive
Failure to thrive in infants may have a nonorganic etiology. Causes include but are not limited to caretaker’s
employment status, social isolation, family stress, substance abuse, postpartum depression, and poor parenting
skills.
What cues indicate a pathologic process?
Key Questions
n Have you had a fever or any signs of illness?
n Have you ever been diagnosed with cancer?
n Have you had a change in urinary or bowel habits?
n Do you experience fatigue?
n In a room where others are comfortable, are you
often too cold or too warm?
n Have you had a change in appetite or thirst?
n If a child: Has your child’s appetite changed?
n If a child: Has your child’s activity level changed?
Acute or Chronic Conditions
Fever associated fatigue and lymphadenopathy may indicate an infection. Chronic conditions, such as cough,
shortness of breath, nausea, vomiting, anemia, fatigue,
weakness, change in moles, pain, abnormal menstrual
bleeding, breast discharge, or chronic headaches, can
contribute to unintentional weight loss. Crohn disease is
an inammatory bowel disease that can be associated
with a reduced appetite.
Unintentional weight loss is a red ag for cancer
occurrence or reoccurrence. Weight loss can occur
from loss of appetite and decreased caloric intake, or
from the body’s inability to absorb nutrients because of
the cancer.
Diabetes
Diabetes is a disease caused by insulin secretion deciency and insulin resistance resulting in elevated
blood glucose levels that do not allow nutrients to enter
cells. Along with weight loss, untreated diabetes is
438 Chapter 36 • Weight Loss/Gain (Unintentional)
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often associated with increased hunger, excessive
thirst, and frequent urination.
Endocrine Disorders
Hyperthyroidism is a condition that speeds up metabolism, thus burning more calories. It is the most common thyroid function disorder. Symptoms include
trembling, insomnia, and hair loss.
Hypothyroidism is when thyroid hormones are insufcient. In less developed countries, it is most often
due to is iodine deciency; however, in the U.S., autoimmune processes are the major cause. Onset of symptoms is insidious and involves every organ system. A
history will reveal symptoms of lethargy, dry skin, cold
intolerance, deepening of voice, and facial pufness.
Cushing syndrome is a result of prolonged exposure to
excessive levels of glucocorticoid cortisol, which has a
catabolic effect on most tissues. Muscle wasting and
weakness is due to generalized protein catabolism.
Appetite/Activity Level Change
A change in an infant or child’s appetite and activity
level is a good indicator of illness. Appetite can decrease with an inactive lifestyle or the presence of
chronic pain, irritable bowel syndrome, or other conditions that might be exacerbated by eating.
What other symptoms might help narrow
the possibilities?
Key Questions
n When was your last cancer screening?
n If a child: Has your child recently switched to
solid food?
n Do you have a family history of cystic brosis?
n Does anyone in your household have a history of
tuberculosis?
Cancer Screening
Routine cancer screening recommendations vary by gender and age and include colon cancer screening, skin
exams, and, for women, periodic screening mammography for breast cancer and Pap smears for cervical cancer
screening. Additional screening for cancer, especially the
use of computed tomography, will depend on associated
symptoms and history of risk factors. The United States
Preventive Services Task Force (USPSTF) conducts rigorous assessments of the scientic evidence for the
effectiveness of a range of clinical preventive services,
including screening, counseling, and preventive medications. The USPSTF recommendations are considered
the gold standard for clinical preventive services
(http://www.ahrq.gov/clinic/uspstx.htm). Lack of regular screening places patients at an increased risk for
undetected cancer.
Diet Change
Infants who were on formula or breast milk but
switched to solid food may exhibit malabsorption conditions (such as lactose intolerance or celiac disease)
that can cause weight loss or slowed weight gain.
Family History
The cystic brosis (CF) gene is autosomal recessive.
Four percent of white persons in the U.S. are estimated
to be carriers (heterozygous) of the CF gene. CF may
present as lack of weight gain between the rst and
sixth months.
Tuberculosis is often associated with reduced
appetite and weight loss and is contracted among
individuals who are exposed to an active infection,
especially within a family or household.
What self-treatment was used? Did it help?
Key Questions
n Are you taking any prescribed or over-the-counter
(OTC) preparations to lose weight?
n How would you describe your eating habits and
dietary practices?
Medication History
There are numerous weight loss drugs on the market
and many of them contain ephedrine, a stimulant that
suppresses appetite. These drugs can be associated
with cardiac arrhythmia and an elevation in blood
pressure. In general, drugs to lose weight are not commonly prescribed but are readily available over the
counter. Individuals may use fasting or purging as a
method of rapid weight loss; fasting also is often done
as an observance of religious or spiritual practice.
Some drugs cause an altered taste sensation and
decease in appetite. Maternal ingestion of drugs while
nursing may affect breast milk supply. Dopamine
agonists, such as cabergoline, reduce prolactin and
are sometimes used therapeutically to stop lactation.
Dopamine antagonists, such as metoclopramide and
most antipsychotics, may increase prolactin and milk
Chapter 36 • Weight Loss/Gain (Unintentional) 439
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production. Other drugs that have been associated
with hyperprolactinemia include selective serotonin
reuptake inhibitors (SSRIs) and opioids.
How serious is this situation? Is this a recent
change?
Key Questions
n How long have you been concerned about your
weight loss?
n Is anyone else concerned about your weight loss?
n What is your ideal or usual weight?
Validate Weight Change
A careful history may document changes in activity
level or a precipitating incident before weight loss was
noticed as a problem.
Concern about Weight Loss
Anorexic patients do not believe they have a weight
loss problem and have a morbid fear of weight gain.
Often family members or friends become concerned
and refer the patient to be evaluated.
Ideal or Usual Weight
Normal or ideal weight for age and gender can be
checked against actuarial tables, such as the 1999
Metropolitan Height and Weight Tables for Men and
Women (http://www.bcbst.com/mpmanual/hw.htm).
Continued unintended weight loss noted for more
than 6 months should be evaluated. Weight can be
veried by using a reliable weight scale. Note if the
person was weighed with or without shoes. Clothing
worn should be lightweight.
Unexplained Weight Gain
Is the weight gain explained by diet
and exercise habits?
Key Questions
n Can you describe what you eat in a typical day?
n Has your eating pattern changed?
n Can you describe your level of physical activity?
expenditure when a person consumes large quanti-
ties of food and food with high calorie content but
gets little aerobic exercise. Factors that contribute
to inactivity are sedentary jobs, TV watching, and
reliance on the automobile. Environmental and ge-
netic factors contribute to a small percentage of
cases of obesity.
Is the weight gain associated with aging?
Key Questions
n What is your age?
n For females: When was your last menstrual
period?
Aging
Normal aging is associated with slower metabolism
and reduced energy requirements.
Menopause
Menopause is dened as the absence of a menstrual
period for one year. About 90% of menopausal women
gain some weight between the ages of 35 and 55.
Hormones have a direct impact on appetite, metabo-
lism, and fat storage. Lower levels of progesterone,
androgen, and testosterone contribute to lower metabo-
lism and weight gain.
Could weight gain be related to other
behaviors?
Key Questions
n How much alcohol do you consume in a week or
a day?
n Do you smoke? If so, how much do you smoke?
How long have you smoked? At what age did you
start smoking? Have you recently quit?
n Do you take any medications?
Alcohol and Smoking
Drinking multiple glasses or bottles of alcohol daily or
weekly will increase calorie intake. Many adults will
gain 5 to 10 pounds in the rst few months after quit-
ting smoking.
Balance of Energy Intake and Expenditure
Maintaining an ideal body weight depends on
achieving a balance of energy intake and energy
expenditure (Table 36-1). Calorie intake can exceed
Medications
Such drugs as corticosteroids, lithium, tranquilizers,
phenothiazines, and tricyclic antidepressants may lead
to uid retention.
440 Chapter 36 • Weight Loss/Gain (Unintentional)
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Table 36-1
Estimated amounts of calories needed to maintain energy balance for various gender and age groups at three different
levels of physical activity. The estimates are rounded to the nearest 200 calories and were determined using the Institute
of Medicine equation.
GENDER AGE (YEARS) SEDENTARY
Child 2-3 1,000 1,000-1,400
Female 4-8
Male 4-8
a
These levels are based on Estimated Energy Requirements (EER) from the Institute of Medicine Dietary Reference Intakes macronutrients report,
2002, calculated by gender, age, and activity level for reference-sized individuals. “Reference size,” as determined by IOM, is based on median
height and weight for ages up to age 18 years and median height and weight for that height to give a BMI of 21.5 for adult females and 22.5 for
adult males.
b
Sedentary means a lifestyle that includes only the light physical activity associated with typical day-to-day life.
c
Moderately active means a lifestyle that includes physical activity equivalent to walking about 1.5 to 3 miles per day at 3 to 4 miles per hour, in
addition to the light physical activity associated with typical day-to-day life.
d
Active means a lifestyle that includes physical activity equivalent to walking more than 3 miles per day at 3 to 4 miles per hour, in addition to the
light physical activity associated with typical day-to-day life.
e
The calorie ranges shown are to accommodate needs of different ages within the group. For children and adolescents, more calories are needed
at older ages. For adults, fewer calories are needed at older ages.
From U.S. Department of Health and Human Services, U.S. Department of Agriculture: Dietary guidelines for Americans, 2005. Available online at
www.healthierus.gov/dietaryguidelines. Accessed August 5, 2010.
Estimated Calorie Requirements (In Kilocalories) for Each Gender
b,c,d
a
c
e
1,000-1,400
1,400-1,800
1,800-2,200
2,400
2,400
2,200
2,000-2,200
1,600-2,000
2,000-2,600
2,800-3,200
3,000
2,800-3,200
2,400-2,800
and Age Group at Three Levels of Physical Activity
Activity Level
MODERATELY ACTIVE
1,400-1,600
1,600-2,000
2,000
2,000-2,200
2,000
1,800
1,400-1,600
1,800-2,200
2,400-2,800
2,600-2,800
2,400-2,800
2,200-2,400
9-13
14-18
19-30
31-50
511
9-13
14-18
19-30
31-50
511
b
1,200
1,600
1,800
2,000
1,800
1,600
1,400
1,800
2,200
2,400
2,200
2,000
ACTIVE
d
e
Could this be caused by an endocrine disorder?
Key Questions
n Has the weight gain been sudden or gradual?
n How much do you weigh now compared to a year
ago?
n Have you noticed any other symptoms or changes in
your appearance?
Acuity of Weight Gain
Women who are premenopausal may note gradual
weight gain over a few years. Some medications, such
as ß-blockers, corticosteroids, and antidepressants, are
associated with weight gain. Edema from congestive
heart failure or renal failure can cause weight gain in a
few days or weeks.
Endocrine Symptoms
Hypothyroidism is associated with fatigue, constipation, and the inability to tolerate cold temperatures.
Cushing syndrome is associated with truncal weight
gain, moon facies, and a “buffalo hump.” Both of these
disorders may develop over an extended period of
time. Polycystic ovary syndrome is associated with
obesity and hirsutism.
DIAGNOSTIC REASONING:
FOCUSED PHYSICAL EXAMINATION
A thorough health history and general physical examination, including screening for psychosocial causes
(see Chapter 3), will help to identify behavioral risk
factors or a pattern of associated symptoms that
suggest a systemic disorder.
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