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414 L.M. Cooney
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Ta b l e 32.4 Factors associated with hospital decline
Bed rest
Sedating or hypnotic drugs
Anticholinergic drugs
Prolonged use of bladder catheters
Use of physical restraints
Returning a patient to the highest level of function requires
a concerted effort on the part of physicians, nursing staff,
therapists, social workers, and discharge planners. The nursing staff and the patient’s family are usually the best observers of the patient’s mental status. A physician’s major role is
to listen. He/she should determine whether the patient has
nighttime confusion, any problems recognizing family members, following commands, or attending to daily tasks.
Although temporary confusion is common following anesthesia, any alterations in mental status that persists beyond
h after surgery, should be evaluated. Medications should
24
be reviewed and a search undertaken to ensure that there are
no acute medical problems causing the patient’s delirium.
Patients who have significant care needs at the time of
hospital discharge and insufficient help at home to provide
these needs may be candidates for a short period of rehabilitation in a subacute or skilled nursing facility. It is essential
that the patient’s care be well coordinated between the physicians and staff at the acute-care hospital and the physician
and staff at the subacute-care facility.
Posthospital Care
The final outcome of any surgical procedure is usually not
clear until 4–6 weeks after the procedure. Posthospital rehabilitation and care play a major role in the success or failure
of these procedures. It is the surgeon’s responsibility to
ensure that each patient receives the posthospital care most
appropriate to his/her needs.
There are three options to posthospital care (1) acute
rehabilitation units or hospitals, (2) subacute care in nursing
homes or “skilled nursing facilities”, and (3) home care.
Medicare has rather strict criteria for patients going to
acute rehabilitation hospitals. Most of these patients have to
fit into the small list of diagnostic categories including
strokes, hips fractures, and other neurologic or orthopedic
problems. To be eligible for this level of care, patients must
need and receive at least 3 h per day of physical, occupational or speech therapy, and require a multidisciplinary
approach from a team lead by physicians skilled in rehabilitation medicine. Most postoperative surgical patients are not
eligible for this level of care, unless they have a complication
such as a stroke.
Medicare does reimburse short-term rehabilitation care in
skilled nursing facilities as long as the patient needs and
receives restorative care or extensive nursing care that could
not be provided at home. Although there is a 100-day maximum for this care, this care is covered only if the patient
continues to make progress in his/her rehabilitation. In addition, there is a very substantial copayment required after the
first 20 days of the nursing home stay. This copayment can
make continued stay at these facilities difficult, if the patient
does not have appropriate secondary insurance coverage.
Subacute Care
Medicare diagnosis-related group (DRG) reimbursement
policies and the push to limit hospital lengths of stay have
moved a great deal of the rehabilitation of older individuals
into skilled nursing facilities. A number of these facilities
have set up special units for “subacute care” [14].
A Swiss group has developed a predictive score to identify patients hospitalized on acute medical service risk of
discharge to a postacute-care facility. These investigators
found that data measured on the first hospital day was predictive of the need for posthospital care. The factors most
predictive of discharge to a postacute-care facility were (1)
the patient’s partner’s inability to provide home care, (2)
inability to self-manage drug regimen, (3) number of active
medical problems on admission, (4) dependency in bathing,
and (5) dependency in transfers from bed to chair [15].
Although it may be logical and reasonable to use loweracuity facilities for rehabilitation, use of these facilities without careful coordination of care between the acute and chronic
care providers can lead to adverse outcomes. Fitzgerald et al.
reported two important studies that demonstrated the problems associated with early transfers to skilled nursing facilities. These studies pointed out that the frequency of transfer
of patients from acute hospitals to skilled nursing facilities
for rehabilitation of a fractured hip more than doubled with
introduction of the Medicare DRG-based reimbursement
system [16, 17]. The greatest concern, however, was the
increase of permanent nursing home placement from 13 to
39% after the introduction of prospective payment. These
studies should caution the surgeon to ensure that temporary
nursing home placements do not become permanent.
Bonar et al. studied the factors associated with permanent
nursing home placement for patients transferred from hospitals to skilled nursing facilities for rehabilitation following hip
fractures. She found that patients who were oriented, younger,
could bathe independently, could transfer and walk independently, and had increased family involvement were more
likely to be discharged from the nursing home to home. In
addition, the number of physical therapy hours available in the
nursing home predicted discharge home [18] (Table 32.5).
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Ta b l e 32.5 Returning home from subacute facilities
Good mental status
Good daily living function
Integrated medical care
Intensity of rehabilitative services
Intensity of discharge planning
Good social support
Several studies have evaluated the outcome of older
patients transferred from hospitals to rehabilitation hospitals,
subacute nursing homes, and traditional nursing homes.
Kramer et al. found that after adjusting for patients’ admission cognitive and physical functions, stroke patients admitted to rehabilitation hospitals were more likely to return to
the community and recover function in ADLs. For patients
with fractured hips, however, there was no difference in outcome for patients admitted to rehabilitation hospitals, subacute nursing homes, or traditional nursing homes [
19]. Kane
et al. also found that stroke patients fared better when treated
in rehabilitation hospitals and rehabilitative nursing homes.
Although healthier hip fracture patients who received rehabilitative nursing home care fared better, the functional
change for sicker hip fracture patients was not different
between regular and rehabilitative nursing homes [20].
Fitzgerald et al., in their studies, found that one interesting fact about hip fracture patients who were able to return to
their own home: patients followed by their own health maintenance physicians in the nursing home had a better chance
of returning home than those who had a separate nursing
home physician [17].
Although subacute-care facilities and traditional nursing
homes may have a role in the rehabilitation of older surgical
patients, it is important to ensure that the care given in these
facilities is as coordinated as possible with the acute-care
facility [21]. Surgeons should recognize that patients with
altered mental status, substantial deficits in their ability to
carry out ADLs, complex medical conditions, and limited
social support at home are at substantial risk for permanent
nursing home placement. The most complex aspect of returning an old person to his or her own home is the discharge
planning process. The surgeon must ensure that the subacutecare facility has all the requisite resources and skills to carry
out this complex process.
The integration of care between the acute-care and chroniccare facility requires, first and foremost, that the physicians
caring for the patient in the nursing home setting be closely
integrated with the acute-care physician. Communication
between the acute-care providers must be complete and ongoing. Systems in which there is integrated physician coverage
appear to have better rehabilitative outcomes and a higher
frequency of patients returning home. An integrated system
of care, in which the staff of the nursing home facility has
complete access to the laboratory, diagnostic imaging, and
other reports of the acute hospital, also increases the potential
for improved care. The transition from an acute hospital to a
skilled nursing facility requires very careful transmission of
clinical information from the acute-care to the chronic-care
providers. The most important information to transmit to the
skilled nursing facility is the name of the responsible physician who has knowledge of the patient’s hospital course, and
how to readily reach that physician [22].
The discharge summary should give careful instructions
for wound care [23], weight-bearing, diet, and medications.
Medication lists should include the last doses given in the
hospital. If medications are to be tapered or discontinued, a
clear outline by date of the tapering course should be included.
All recent significant laboratory tests should be listed within
the discharge summary. Those tests that are still pending
should be listed with appropriate follow-up outlined.
The goals of the subacute stay should be outlined. If the
patient is on anticoagulation, the orders for anticoagulant
should be listed with goal results for INRs, along with the
most recent dose of anticoagulants and INR results.
Nutritional problems should be identified during the acute
hospitalization and goals of nutritional therapy in the skilled
nursing facility should be outlined. Nutritional supplements
should be given at least 1 h before a meal. If parenteral feeding is used, instructions for these feedings should be clearly
outlined [24].
The physician ultimately responsible for the patient’s
rehabilitation is the attending surgeon. He or she must ensure
that those caring for the patient after hospitalization have a
clear outline of the therapies indicated and should have easy
access to that surgeon to answer any questions that they
might have. Electronic access between the skilled nursing
facility and discharging hospital is best, as this access could
provide laboratory, diagnostic imaging, and operative and
clinical information to the skilled nursing facility staff. In the
final analysis, returning an individual to the highest possible
level of function requires a concerted effort on the part of
surgeons, physicians, nurses, physical therapists, discharge
planners, and social workers to provide the patient with the
highest possible level of function.
Patients who are confused or delirious at the time of hospital discharge do not do well in subacute-care facilities. The
best management of delirious patients is to return them, as
quickly as possible, into their own home environment. Another
health care facility can often worsen patient’s confusion. It is
very difficult to rehabilitate a confused patient. If the patient’s
family cannot take the patient home in this condition, care
must be coordinated very closely between the acute providers
and physicians and nursing staff at the skilled nursing facility.
At the time of hospital discharge, the discharging surgeon
must ensure (1) that the patient’s mental status will allow
continued rehabilitation at a subacute or home setting,
(2) that the appropriate medical and rehabilitation care is
416 L.M. Cooney
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well outlined to the subacute or home care providers, and (3)
that those providing chronic care to the patient have immediate access to the responsible surgeon. Surgeons must recognize that this posthospital care is an important part of the
recovery period from surgery and is the responsibility of the
discharging surgeon.
References
1. Katz S, Ford A, Moskowitz R et al (1963) Studies of illness in the
aged: the index of ADL; a standardized measure of biological and
psychosocial function. JAMA 185:94–99
2. Walter LC, Brand RJ, Counsell SR et al (2001) Development and
validation of a prognostic index for 1-year mortality in older adults
after hospitalization. JAMA 285(23):2987–2994
3. Inouye SK, Wagner DR, Acampora D et al (1993) A predictive
index for functional decline in hospitalized elderly medical patients.
J Gen Intern Med 8:645–652
4. Hirsch CH, Sommers L, Olsen A et al (1990) The natural history of
functional morbidity in hospitalized older patients. J Am Geriatr
Soc 38:1296–1303
5. Creditor MC (1993) Hazards of hospitalization of the elderly. Ann
Intern Med 11:219–223
6. Gillick MR, Serrell NA, Gillick LS (1982) Adverse consequences
of hospitalization in the elderly. Soc Sci Med 16:1033–1038
7. Warshaw GA, Moore JT, Friedman SW et al (1982) Functional disability in the hospitalized elderly. JAMA 248:847–850
8. Inouye SK (1994) The dilemma of delirium: clinical and research
controversies regarding delirium in hospitalized elderly medical
patients. Am J Med 97:278–288
9. Miller CW (1978) Survival and ambulation following hip fracture.
J Bone Joint Surg Am 60:930–933
10. Morrison RS, Siu AL (2000) Survival in end-stage dementia following acute illness. JAMA 284(1):47–52
11. Ferri CP, Prince M et al (2005) Global prevalence of dementia:
a Delphi consensus study. Lancet 366:2112–2117
12. Inouye SK, Charpentier PA (1996) Precipitating factors for delirium
in hospitalized elderly persons: predictive model and interrelationship with baseline vulnerability. JAMA 275:852–857
13. Pompei P, Foreman M, Rudberg M et al (1994) Delirium in hospitalized older persons: outcomes and predictors. J Am Geriatr Soc
42:809–815
14. Cotterill PG, Gage BJ (2002) Overview: medicare post-acute care
since the Balanced Budget Act of 1997. Health Care Financ Rev
24(2):1–6
15. Simonet ML, Kossovsky MP, Chopard P, Sigaud P, Perneger TV,
Gaspoz JM (2008) A predictive score to identify hospitalized
patients’ risk of discharge to a post-acute care facility. BMC Health
Serv Res 8:154
16. Fitzgerald J, Fagan L, Tierney W et al (1987) Changing patterns of
hip fracture care before and after implementation of the prospective
payment system. JAMA 258:218–221
17. Fitzgerald J, Moore T, Dittus R (1988) The care of elderly patients
with hip fracture: changes since implementation of the prospective
payment system. N Engl J Med 319:1392–1397
18. Bonar S, Tinetti M, Speechley M et al (1990) Factors associated
with short- versus long-term skilled nursing facility placement
among community-living hip fracture patients. J Am Geriatr Soc
38:1139–1144
19. Kramer A, Steiner J, Schlenker R et al (1997) Outcomes and costs
after hip fracture and stroke: a comparison of rehabilitation settings.
JAMA 277:396–404
20. Kane R, Chen Q, Blewett L et al (1996) Do rehabilitative nursing
homes improve the outcomes of care? J Am Geriatr Soc 44:
545–554
21. Prvu Bettger JA, Stineman MG (2007) Effectiveness of multidisciplinary rehabilitation services in post-acute care: state-of-the-science.
A review. Arch Phys Med Rehabil 88:1526–1534
22. Marcantonio ER, Yurkofsky M (2003) Subacute care. In: Hazzard
WR, Blass JP, Halter JB, Ouslander JG, Tinetti M (eds) Principles
of geriatric medicine and gerontology, 5th edn. McGraw Hill, New
York, pp 181–196
23. Thomas DR, Kamel HK (2000) Wound management in postacute
care. Clin Geriatr Med 16(4):783–803
24. Morley JE (2000) Management of nutritional problems in subacute
care. Clin Geriatr Med 16(4):817–831
Section IV
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Endocrine System/Breast
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Chapter 33
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Invited Commentary
Samuel A. Wells
Age-related alterations in endocrine function are important
considerations in the surgical patient. Because the endocrine
system is integrally related to virtually all bodily functions, it
is unreasonable to think of the singular effects of a specific
hormone deficiency. It is impossible to cover all aspects of
the endocrinology of aging; however, we address some of the
most significant.
Arguably, the most important endocrine change associated
with aging arises in the pancreas and relates to the decreased
availability of insulin. Forty percent of individuals aged
65–75 years have impaired glucose tolerance, the incidence
of which increases with age. The abnormality goes undetected
in many elderly patients, and they are at risk for developing
vascular, ocular, and neurologic complications. In addition to
decreased insulin secretion from the pancreatic beta cell,
physical inactivity, poor diet, increased body weight, and
decreased lean body mass contribute to glucose intolerance.
The incidence of thyroid abnormalities including autoimmune thyroiditis, the metabolic states of hypothyroidism and
hyperthyroidism, thyroid nodules, and thyroid cancer also
increases with age. The surgeon must be aware of the possibility of occult thyroid disease in the elderly. The failure to
recognize the presence of occult hypothyroidism or hyperthyroidism in acutely ill surgical patients may result in
increased operative and perioperative mortality.
There are significant decreases in cortical and trabecular
bone as one ages. Loss of bone mineralization is particularly
problematic in women, where trabecular bone loss accelerates
at menopause and reaches a rate of 4% per year. Estrogen deficiency accounts for a 15–20% decrease in skeletal density,
which is increased further in the presence of hyperparathyroidism, a disease that occurs primarily in postmenopausal women.
Understandably, there is an increase in fracture rate in elderly
patients not only due to decreased bone density but also because
of a decrease in muscle strength and impaired coordination.
S.A. Wells (*)
Professor of Surgery, Department of Surgery,
Washington University Medical Center, St. Louis, MO, USA
e-mail: wellss@wudosis.wustl.edu
Menopause, one of the most dramatic age-related changes,
is primarily associated with the loss of cyclic estradiol production. Menopause appears to be brought on by changes in
both the ovarian follicles and the hypothalamus and pituitary.
Long-term estrogen replacement therapy is beneficial for the
skeleton, cardiovascular system, reproductive tract, skin, and
central nervous system; however, estrogen replacement is
associated with a modest but definitely increased incidence
of breast cancer.
In aging men, there is a decline in serum testosterone levels and an accompanying reduction in the number of Leydig
cells. Studies show that testosterone replacement in elderly
men is associated with increased muscular strength, cognition, and red blood cell mass. However, testosterone administration has a stimulatory effect on the prostate, and the risk
of enhancing the growth of an occult prostate cancer is a
definite risk.
Hormonal changes also occur in the adrenal cortex, characterized by a decrease in circulating levels of dehydroepiandrosterone (DHEA), and in the pituitary gland, characterized
by a reduction in growth hormone and insulin-like growth
factor. There have been prospective randomized controlled
trials in older adults, of DHEA administration compared to
placebo. In subjects receiving DHEA, compared to those
receiving placebo, circulating levels of DHEA and androgen
were restored, and there was a sense of improved well-being.
The risk of administering these agents relates to the direct or
indirect stimulatory effect on the breast and prostate gland
and perhaps other tissues. Similarly, growth hormone, administered in prospective randomized placebo-controlled trials,
has been associated with increased muscle strength and bone
mineral content. It has already been shown in patients with
fractures or burns that administration of growth hormone has
clear benefit in wound healing and return to independent living. As with DHEA, the question remains whether adverse
effects will become evident with long-term administration of
growth hormone. There is the possibility that administration
of selected hormones would have a beneficial effect on the
elderly surgical patient, as minimal adverse effects have been
seen with their short-term administration.
R.A. Rosenthal et al. (eds.), Principles and Practice of Geriatric Surgery,
DOI 10.1007/978-1-4419-6999-6_33, © Springer Science+Business Media, LLC 2011
419
420 S.A. Wells
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The surgeon must understand that both profound and
subtle changes occur in the endocrine system with aging
and that these alterations influence the response of the older
patient to surgical procedures. Replacement therapy for
endocrine deficiencies is clearly indicated in the elderly
patient whether in the emergent or the elective setting.
However, much work remains to be done on the evaluation
of hormonal administration in healthful elderly persons to
clarify whether the benefits outweigh the risks. The question
is important, as the results will influence how elderly patients
respond to surgical treatment and to their underlying disease
process.
Chapter 34
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Surgical Disorders of the Thyroid in the Elderly
Leslie S. Wu, Julie Ann Sosa, and Robert Udelsman
CASE STUDY
JK is a 75-year-old woman with a right anterior neck
mass identified on physical examination by her cardiologist. She described a globus sensation and dysphagia
with solid foods, and had subjective hoarseness over the
last year. She did not have a history of head or neck radiation, and there was no family history of glandular abnormalities. Her past medical history was significant for
hypertension, hyperlipidemia, atrial fibrillation on
chronic warfarin therapy, diabetes mellitus, osteopenia,
and arthritis. Her past surgical history was notable for a
cholecystectomy, hysterectomy for uterine fibroids, and
left breast lumpectomy and radiation therapy for ductal
carcinoma in situ. Family history is significant for “bad
hearts.” She was a former smoker. Her medications
included warfarin, metoprolol, amlodipine, simvastatin,
glucophage, glipizide, niacin, fish oil, calcium supplements with vitamin D, multivitamin, and acetaminophen
as needed.
Physical examination revealed a well-developed
woman in no acute distress. Her vital signs were within
normal limits, and she appeared euthyroid. Focused exam
was notable for a nontender 4-cm firm but mobile mass
in the right anterior neck. The trachea was distracted
slightly into the contralateral neck. The left thyroid lobe
contained no palpable nodules. There was no cervical
lymphadenopathy. Pemberton sign was absent, and there
was no carotid bruit. The remainder of her physical exam
was unremarkable.
On blood work, the patient was biochemically euthyroid with a thyroid-stimulating hormone (TSH) 2.5 mIU/L
(normal 0.4–4.0 mIU/L). JK’s geriatrician referred her to
an endocrinologist, who, in turn, consulted a thyroid surgeon. JK underwent a dedicated neck ultrasound, which
revealed a 60-g thyroid and a 4-cm nodule in the right
lobe. It was hypoechoic with a small cystic component,
microcalcifications, an irregular border, and possible
extension into the overlying strap muscle. The left lobe
contained two 4-mm nodules that were too small to characterize. Ultrasound-guided fine-needle aspiration (FNA)
of the dominant right nodule was performed.
Cytopathology was consistent with papillary thyroid
cancer.
Introduction
The proportion of elderly people is growing steadily in
Western societies as a consequence of increased life expectancy and reduced birth rates. Americans aged 80 years and
older constituted 3.3% of the population in 2000; this is
projected to increase to 7.7% in 2050 and 8.2% by 2070.
In comparison, Americans 65–79 years of age constituted
J.A. Sosa (*)
Department of Surgery, Maine Medical Center,
22 Bramhall St., Portland, ME, USA
R.A. Rosenthal et al. (eds.), Principles and Practice of Geriatric Surgery,
DOI 10.1007/978-1-4419-6999-6_34, © Springer Science+Business Media, LLC 2011
9.3% of the population in 2000 and are projected to increase
to 12.5% by 2050 and 12.9% by 2070 [1]. This phenomenon has generated numerous studies aimed at clarifying
the physiologic and pathologic aspects of aging. Thyroid
dysfunction can have profound clinical implications for
elderly patients. Thyroid nodules are common, and the
incidence of thyroid cancer increases with age.
Thyroid disease is common; 6.6% of the US population
has thyroid disease, requires thyroid hormone supplementation, or both [2]. Based on results of autopsies performed on
the general population, thyroid nodules have been found in
up to 50% of asymptomatic patients [3]. The incidence of
thyroid cancer has increased from 3.6 per 100,000 in 1973 to
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8.7 per 100,000 in 2002 – a 2.4-fold increase – with 87% of
the increase due to the diagnosis of small differentiated thyroid cancers [4]. The association between increasing age and
incidence of thyroid nodules makes diagnosis and treatment
an important public health issue.
All thyroid diseases are encountered in the elderly; however, their prevalence and clinical expression differ from
those observed in younger patients. Symptoms of aging can
be confused easily with hypothyroidism. The clinical manifestations of thyroid dysfunction can be more vague, subtle,
and hidden by a background of coexistent disease.
Interpretation of thyroid function studies can be problematic
in elderly patients, owing to difficulty in differentiating
physiologic age-associated changes from alterations secondary to acute or chronic nonthyroidal illnesses [5]. And finally,
the medical and surgical treatment of thyroid disease in the
elderly is associated with an increased risk of complications
attributed to the treatment itself [6].
Thyroid Function
The thyroid gland synthesizes the hormones thyroxine (T4)
and triiodothyronine (T3), iodine-containing amino acids that
regulate the body’s metabolic rate. Adequate levels of thyroid
hormone are necessary in infants for normal development of
the central nervous system, in children for normal skeletal
growth and maturation, and in adults for normal function of
multiple organ systems [7]. Thyroid dysfunction is one of the
most common endocrine disorders encountered in clinical
practice. While abnormally high or low levels of thyroid hormones can be tolerated for long periods of time, usually there
are symptoms and signs of thyroid dysfunction.
The effects of thyroid hormones are diffuse and important
(Table 34.1). Thyroid hormones increase the activity of
membrane-bound Na+-K+ adenosine triphosphate (ATP)-ase,
increase heat production, and stimulate oxygen consumption
(“calorigenesis”). Thyroid hormones also affect tissue growth
and maturation, help regulate lipid metabolism, increase
cardiac contractility by stimulating the expression of myosin
protein, and increase intestinal absorption of carbohydrates
(Fig. 34.1) [8].
The usual biochemical measures of thyroid function, such
as T3, T4, and thyroid-binding protein levels, change little
with advancing age in the absence of systemic illness.
Similarly, thyrotropin (TSH) levels and the production of
Fi g u r e 34.1 Hypothalamus–pituitary–thyroid axis with hormonal feed-
back mechanisms (reproduced with permission from Thyroid. In:
Basow, DS, (Ed), Uptodate, Waltham, MA, 2010. Copyright © 2010
UpToDate, Inc. For more information, visit
http://www.uptodate.com).
Ta b l e 34.1 Physiologic effects of thyroid hormones
Target tissue Effect Mechanism
Heart
Adipose tissue Catabolic Stimulate lipolysis
Muscle Catabolic Increase protein breakdown
Bone Developmental and metabolic Promote normal growth and skeletal development; accelerate bone turnover
Nervous system Developmental Promote normal brain development
Gut Metabolic Increase rate of carbohydrate absorption
Lipoprotein Metabolic Stimulate formation of LDL receptors
Other Calorigenic Stimulate oxygen consumption by metabolically active tissues
ATP adenosine triphosphate; LDL low-density lipoprotein
Chronotropic Increase number and affinity of beta-adrenergic receptors
Inotropic
Enhance responses to circulating catecholamines
Increase proportion of alpha myosin heavy chain (with higher ATPase activity)
(exceptions: adult brain, testes, uterus, lymph nodes, spleen, anterior pituitary)
Increase metabolic rate
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TSH in response to thyrotropin-releasing hormone (TRH)
administration are relatively constant with increasing age
[9]. In the past, hypothyroidism was considered an integral
part of aging; however, more recent studies suggest that
physiologic aging is associated with normal thyroid function
[10]. The half-life of T4 increases from 6.7 days in young
adults to 9.3 days in those aged 80–90 years due to decreases
in both fractional turnover rate and the distribution space of
T4. Peripheral conversion of T4–T3 is decreased, but the
intrathyroidal conversion is increased, resulting in relatively
stable T3 levels in the elderly [11].
The Whickham survey documented the prevalence of thyroid disorders in a sample of 2,779 British adults, and the
20-year follow-up study was published in 1995 [12, 13]. The
annual incidence of hypothyroidism was found to increase
with age and correlate with the presence of thyroid autoantibodies or elevated TSH levels. Aging often is associated with
an increased prevalence of antithyroid antibodies, but this
age-dependent increase is observed commonly in unselected
elderly subjects and not in healthy elderly populations
selected for the absence of clinical or subclinical illnesses
[14]. This suggests that thyroid autoimmune phenomena
may not be the consequence of the aging process itself but,
rather, an expression of age-associated disease.
Measurement of serum TSH, a sensitive indicator of free
thyroid hormone concentration in the presence of normal pituitary function, is often all that is required as a screening test for
thyroid function. A decision analysis by Danese et al. reported
that screening for thyroid disease by TSH measurement was
particularly cost-effective in elderly female patients, as the
clinical symptoms of thyroid dysfunction may be atypical in
this age group [19]. Analyses of free hormone levels deter-
mine what is available for cellular metabolic regulation. In
addition to thyroid function tests, diagnostic determination of
thyroid autoantibodies can be useful. Antibodies to the TSH
receptor are present in Graves’ disease and also can be seen
with other forms of autoimmune thyroid disease, such as
Hashimoto’s thyroiditis. Antithyroid peroxidase antibodies
and antithyroglobulin antibodies are seen with all forms of
autoimmune thyroid disease and may be present in patients
with multinodular goiter. Assessment of the thyroid also
should include imaging studies, such as ultrasound, nuclear
medicine uptake scans, computed tomography (CT) scans,
and magnetic resonance imaging (MRI).
Hypothyroidism
Thyroid Dysfunction
Thyroid function can be evaluated by several biochemical
measures, including total or free T3 and T4, and TSH [15].
The high incidence of comorbid illness in elderly people can
confound assessment of thyroid function. Malnutrition,
infection, sepsis, major surgery, poorly controlled diabetes
mellitus, hepatic disease, renal failure, cerebrovascular disease, heart failure, malignancy, trauma, burns, and coma are
all associated with alterations in thyroid function tests [16].
Depending on severity, stage, and drug effects, these nonthyroidal illnesses are associated with changes in the parameters
of thyroid function that include low serum T3, normal to low
T4, and normal to low or elevated TSH – the “euthyroid sick
syndrome.” Among acutely ill patients, 70% show a low T3
state, and 30–50% of patients in intensive care units have low
serum T4 levels [17].
Findings in patients’ personal and family histories indicate
increased risk of developing thyroid dysfunction. Risk factors
in personal history include goiter, surgery or radiotherapy
affecting the thyroid gland, previous thyroid dysfunction,
vitiligo, diabetes mellitus, pernicious anemia, leukotrichia,
and medications, such as lithium carbonate and amiodarone,
and iodine-containing compounds. Pertinent factors in family
history are thyroid disease, pernicious anemia, diabetes
mellitus, and primary adrenal insufficiency [18].
Epidemiology
The balance between central production and peripheral
action of T3 and T4 is required for a euthyroid state. Clinical
hypothyroidism usually is associated with decreased hormone
production in the thyroid gland, although states of limited
thyroid hormone activity in the periphery also can occur. In
many underdeveloped countries or iodine-poor regions, lack
of sufficient iodine intake explains a large percentage of
hypothyroid conditions [20, 21]. In more developed countries, most cases of adult primary hypothyroidism (due to
direct thyroid failure) are secondary to chronic autoimmune
(Hashimoto’s) thyroiditis, radioactive iodine (RAI) therapy,
or surgery. Disorders of the pituitary or hypothalamus can
cause diminished TSH secretion, producing hypothyroidism
as a secondary or tertiary result. Finally, a host of medications, including the thioamide antithyroid drugs propylthiouracil (PTU) and methimazole (MMI), can produce
hypothyroidism (Table 34.2).
There are two types of primary hypothyroidism. Clinical or
overt primary hypothyroidism is characterized by elevated
serum TSH and decreased serum T3 and T4 levels. Patients
with subclinical primary hypothyroidism show mildly elevated serum TSH concentrations and normal serum thyroid
hormone levels. Subclinical hypothyroidism is the most
common thyroid dysfunction nationwide, with a markedly
increased prevalence in the elderly, ranging from 4 to 15%
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