Management of pain in persons with dementia - Alzheimer...

Management of pain in persons with dementia

Pain is a common medical condition in older persons; especially residents in long
term care (LTC) settings. Pain is defined as a sensory and emotional experience
associated with actual or potential tissue damage. Chronic persistent pain occurs in
24% of LTC residents while only 29% are free of all pain. Most, i.e., 74%,
demented nursing home residents have some pain and the majority, i.e., 70%, is
untreated or under-treated. Pain can have multiple origins; however, discomfort
produced by musculoskeletal disease is the most common problem in the older
person, e.g., arthritis 42%, bone fracture 12%. Untreated or under-treated pain can
produce significant suffering as well as agitation and behavioral problems in
persons with dementia. Regular administration of acetaminophen can reduce
agitation in more than one-half of agitated, demented patients with pain.
Assessment and management of pain is an important responsibility of any clinical
management team. Dementia patients are less likely to receive analgesics despite
the fact that they experience suffering equal to cognitively intact individuals.


Neuroanatomy of Chronic Pain

The therapy for pain should target each level within the nervous system that
produces the noxious sensory stimulus. The brain perceives pain via a complex
series of emotional and intellectual responses to pathways that begin at the level of
the pain-sensing organ and end with our interpretation of the sensory stimulus (See
Table 3). Pain sensors are located throughout the skin, joints, bones, and organs
within the body. The pain associated with a burn, bruise, or broken bone is
perceived through specialized nerve endings in each tissue. The sensory nerve
impulse is transmitted to the spinal cord via peripheral nerves. The spinal cord
receives the raw information and transmits the sensation to a relay station in the
base of the brain termed the thalamus where the information is organized. The
thalamic neurons then relay the organized information to the brain region that
integrates sensory information called the parietal lobe. The parietal lobe recruits
limbic systems to judge the level of distress and develop an emotional response to
this discomfort, e.g., temporal and frontal lobes. Malfunction at any level in the
pain circuit can produce misinterpretation of painful or noxious stimuli. Visceral
sensations from bladder, bowel, stomach, gallbladder, etc. are transmitted to a
distinct brain region buried beneath the temporal lobe called the insular cortex.
Alzheimer’s disease does not damage sensory pathways from the body and internal
organs; however, brain regions that interpret these messages are altered by the
disease. Stimulation or damage at each sensory processing level can produce
specific pain syndromes that require distinct therapeutic interventions. The
interpretation of pain in dementia patients is complicated because they misidentify,
under-recognize, over report, or ignore painful stimuli due to damaged cortical
centers that integrate sensory information, i.e., parietal lobe, insular cortex. The
normal intellectual expressions of pain, such as verbal complaints or help-seeking,
are replaced by agitation, hostility, and aggression.


Pain Assessment in Dementia

The assessment of pain in the demented patient requires a review of medical
records to determine the timing and sequence of the painful experience as well as a
careful physical examination. Demented patients require a mental status
examination to determine their ability to interpret pain, or ask for medication, as
well as exclude depression or anxiety that might intensify the painful sensation.
Chronic pain can produce depression and many patients experience less discomfort
when treated with antidepressants. Tricyclic antidepressants like Elavil are helpful
in younger patients but this medication causes severe confusion in demented
patients. Other TCAs with fewer side effects, e.g., desipramine and nortriptyline,
are as effective as Elavil at equivalent doses.

Recognition of pain in demented patients usually requires direct observation as
these individuals frequently suffer from receptive and expressive aphasia. Tense
body language, sad facial expressions, fidgetiness, loud perseverative verbal
outbursts, and immobilization of specific body parts may indicate pain. Facial
expressions that include clenched teeth, widely opened eyes, or tightly shut eyes
may suggest the patient is experiencing significant pain. Distress or agitation
during attempts at repositioning, transfer, or ambulation may indicate unrecognized
arthritic or orthopedic pain. Episodic pain with secondary diaphoresis may
indicate angina. Some verbal outbursts may result from chronic, untreated or
under-treated pain. The frequency and intensity of these pain symptoms must be
documented in the record. Pain charts are often helpful.


Management of Acute and Chronic Pain in Dementia

The first step in pain management is assessment of the discomfort. Acute pain
syndromes commonly follow injuries, surgical procedures, etc. and require
standard analgesic or narcotic management. Acute pain syndromes are expected to
last for brief periods of time, i.e., less than six months. Pain that persists for over
six months is termed chronic pain. Chronic non-malignant pain requires a more
complex strategy to minimize the use of narcotics and maximize non-
pharmacological interventions. Acute pain rarely produces other long-term
psychological problems, such as depression, although acute discomfort will
produce distress manifested by acute anxiety or agitation in the demented patient.
Mildly demented patients can become agitated or anxious with pain because they
rapidly forget explanations or reassurances provided by staff. Amnestic
individuals may forget to ask for PRN non-narcotic analgesics such as
acetaminophen and these patients need regularly scheduled medications.
Disoriented patients do not realize they are in a health care facility and aphasic
patients may not comprehend the staff’s inquiry about pain symptoms.

The symptoms of pain expressed by patients with moderate to severe dementia
include anxiety, agitation, screaming, hostility, wandering, aggression, failure to
eat, and failure to get out of bed. A small number of demented individuals with
serious injury may not complain of pain, e.g., hip fractures, ruptured appendix, etc.
Assessment of pain in the demented patient requires verbal questioning and direct
observation to assess for behaviors that suggest pain. Standardized pain
assessment scales should be used for all patients; however, these clinical
instruments may not be valid in persons with dementia or psychosis. The past
medical history may be valuable in assessing the demented resident. Individuals
with chronic pain prior to the onset of dementia usually experience similar pain
when demented, e.g., compression fractures, angina, neuropathy, etc. These
individuals can be monitored carefully and non-narcotic pain medication can be
prescribed as indicated, e.g., acetaminophen on a regular basis, anticonvulsants for
neuropathy.


Management of Chronic Pain

The management of pain in any person requires careful consideration about the
contribution of each component of the pain circuit to the painful stimulus (See
Table 3). Neuropathic pain is produced by dysfunction of the nerve or sensory
organ that perceives and transmits noxious stimulus to the level of the spinal cord.
Radicular pain, i.e., pain occurring in a specific nerve pattern, is more consistent
with dysfunction of a specific nerve, e.g., sciatica that radiates down the back of
the leg. Persons with serious back disease may have herniated discs that compress
specific nerve roots. This pain is often positional and produces spasms of the
musculature in the back.

Damage to the spinal cord can produce chronic, neuropathic or non-localizing pain.
This discomfort is commonly seen in persons with traumatic back injures. Strokes
in the thalamus can produce a chronic pain syndrome called thalamic pain by
misinforming the brain that a painful stimulus has been received.

The brain interprets pain in a highly organized systematic pattern. Discrete brain
regions interpret and translate painful stimuli from specific body regions, e.g., arm,
leg, etc., misfire in that discrete brain region will misinform the person that pain or
discomfort is being experienced in that limb or part of the trunk. A person who
loses a limb from trauma or amputation may continue to experience painful
sensations in the distributions for that limb termed phantom limb pain.

Management of chronic pain involves three elements (1) physical interventions, (2)
psychological interventions, (3) pharmacological interventions. Physical
interventions include basic physiotherapy that incorporates warm or cool
compresses, massage, repositioning, electrical stimulation and many other
treatments. Dementia patients need constant reminders to comply with physical
treatments e.g., using compresses, sustaining proper positioning, etc., and many do
not cooperate with some interventions, like nerve stimulators or acupuncture.
Physical interventions are particularly helpful in older persons with
musculoskeletal pain regardless of cognitive status. Psychological interventions
usually require intact cognitive function e.g., relaxation therapy, self-hypnosis, etc.
Demented patients generally lack the capacity to utilize psychological
interventions; however, management teams should provide emotional support to
validate the patient’s suffering associated with pain. Demented patients may
experience more suffering from pain than intellectually intact individuals because
they lack the capacity to understand the cause of their discomfort. Fear, anxiety,
and depression frequently intensify pain.

Pharmacological management begins with the least toxic medications and follows
a slow progressive titration until pain symptoms are controlled. Clinicians must
distinguish between analgesia and euphoria. Some medications that appear to have
an analgesic or pain relieving effect actually have an euphoric effect, which
diminishes the patients’ concern about perceived pain. The goal of pain
management is to remove the suffering associated with the painful stimulus rather
than making the patient euphoric or high to the point where they no longer care
whether they experience pain. Euphoria-producing medications can cause
confusion, irritability, and behavioral lability in patients with dementia. Narcotic
addiction is not a common concern in dementia patients as these individuals have a
limited life expectancy and rarely demonstrate drug-seeking behaviors.

Pharmacological interventions always begin with the least toxic, i.e., least
confusing, medications. A regular dose of acetaminophen up to 4 grams per day
will substantially diminish most pain and improve quality of life. Clinical studies
show that regular Tylenol reduced agitation in over half the treated patients.
Chronic arthritic pain with inflammation of the joints may also respond to non-
steroidal anti-inflammatories (NSAIDS) or Cox-2 inhibitors. The gastrointestinal
toxicity associated with NSAIDS is greater than that of Cox 2 inhibitor
medications. Patients who fail to respond to non-narcotic analgesics should
receive narcotic-like medications, i.e., tramadol. Patients who fail to respond to
maximum doses of tramadol, i.e., 300 mgs per day, may require narcotic
medications.

Calcitonin is effective in some chronic pain associated with osteoporosis and
fractures. Osteoporotic fractures are common painful complications of aging and
produce significant distress in demented and non-demented individuals. Studies
demonstrated that 50 to 100 units of nasal calcitonin would substantially reduce
discomfort associated with fractures. Calcitonin suppositories were also effective
for treatment of long-term bone related pain.


Opiate Management Of The Demented Resident

The prescription of opiates for dementia patients requires attention to the need to
relieve distress caused by pain and the potential for medication toxicity. The
World Health Organization has proposed a three-step analgesic ladder for use in
pain caused by cancer, which may be a useful guide in patients with dementia, as
well. Pain treatment starts with non-narcotic medications, and moves up the ladder
as indicated by patient response and tolerability of therapies. At any step in the
ladder, co-prescription of non-opiate analgesics (acetaminophen, NSAIDS, COX-2
inhibitors), as tolerated, can provide synergistic relief and reduce the doses of
opiate necessary for good pain control.

The choice of specific opiate compounds depends on the situation. For intermittent
pain, short-acting immediate release opiates may be sufficient (Step 2 on the WHO
ladder). Many of these are available in preparations combined with acetaminophen
or an NSAID. Codeine preparations provide a relatively mild analgesic effect, but
can be as “constipating” as stronger narcotics. Preparations containing meperidine,
pentazocine, and propoxyphene can worsen confusion in dementia patients and
should generally be avoided in this population. Mixed agonist-antagonist
medications (e.g., butorphanol, nalbuphine, pentazocine) are problematic for use in
this setting, particularly if the patient has been exposed to other opiates.
Hydrocodone, morphine, and oxycodone preparations are preferred for pain
requiring intermittent or short-term opiate treatment.

Severe pain that is refractory to less aggressive measures can be treated with WHO
Step 3 agents such as fentanyl, hydromorphone, morphine, or oxycodone. Patients
with persistent severe pain require continuous dosing around-the-clock to avoid
breakthrough pain. To avoid every 2 to 4 hour dosing around the clock, sustained
release preparations are used once the patient’s 24-hour dose need is determined
using immediate-release preparations. Breakthrough (or rescue) doses should also
be provided as a PRN; a dose of an immediate-release preparation available every
2-4 hours PRN is ideal for breakthrough dosing. A breakthrough dose of 10% of
the total 24-hour sustained-release dose is a good rule of thumb. If more than one
or two breakthrough doses are needed on a regular basis, the sustained-release dose
should be adjusted. The goal of opiate therapy for severe pain is to control as
much of the pain as possible with the sustained-release medication. Common side
effects of opiate therapy include constipation, dry mouth, nausea, and sedation.
Constipation is sufficiently common in elderly patients with dementia and
prophylactic treatment (e.g., stool softeners) is indicated when opiate therapy is
initiated. Bowel function should be closely monitored while on opiate therapy to
avoid impaction that may produce agitation or diminished oral intake.

Chronic analgesic therapy should be continued in severely demented patients
unless re-evaluation shows resolution of pain. Severely aphasic patients must be
carefully observed for non-verbal expression of pain after discontinuation of
medication. A slow taper off opiates is indicated to avoid withdrawal symptoms in
tolerant patients and to allow monitoring for re-emergence of pain.

Dose conversion tables (examples attached) can be used to convert from one opiate
to another (if the first agent is poorly tolerated) or to calculate an appropriate
breakthrough dose of an immediate-release preparation for sustained-release agents
without an immediate-release form (e.g., fentanyl).

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Table 1. WHO 3-step ladder

Step 1. Mild pain

Aspirin (ASA)
Acetaminophen (Acet)
Nonsteroidal anti-inflammatory drugs (NSAIDs)
± Adjuvants

Step 2. Moderate pain

Acet or ASA +
Codeine
Hydrocodone
Oxycodone
Dihydrocedeine
Tramadol (not available with ASA or Acet)
± Adjuvants

Step 3. Severe pain

Morphine
Hydromorphone
Methadone
Levorphanol
Fentanyl
Oxycodone
± Nonoploid analgesics
± Adjuvant

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Adjuvants refers either to medications that are coadministered to manage an adverse effect of an opioid, or to so-called adjuvant analgesics that are added to enhance analgesia.
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In 1986, the World Health Organization (WHO) developed a 3-step conceptual model to guide
the management of cancer pain. It provides a simple, well-tested approach for the rational
selection, administration, and titration of a myriad of analgesics. Today, there is worldwide
consensus favoring its use for the medical management of all pain associated with serious illness.


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Table 2. Narcotic dosing ranges and equivalent doses
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Table 3. Correlating the anatomy of pain to therapy
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