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Coughing in the Elderly
Fae Farrer, BPharm
Amayeza Info Centre
Abstract
Coughing is a normal reflex reaction due to stimulation of the cough receptors in the brain. Generally, elderly patients have an increased incidence of illnesses and take more medications compared to
younger patients.1 This potentially increases risks of drug interactions and side effects. Because coughing can be a symptom of another underlying disease, a careful evaluation of signs, symptoms and other
factors must be undertaken when an elderly patient presents with a cough.
Introduction
Coughing is one of the most common symptoms for which
treatment is sought in the community pharmacy.3 The cough
reflex is a vital part of the body’s defence mechanisms.4 Along
with other mechanisms, coughing helps to protect the lungs
from particles that have been inhaled. The expulsion of air during a cough will force the particles out of the airways.
Elderly patients tend to have an increased incidence of illnesses, including those affecting the lungs. Although a cough may
be a trivial symptom, it can also point to a more serious underlying disease. Therefore, it is important to identify the cause of
the cough and if this is not possible, to refer the elderly patient
for further medical attention.
Who is elderly?
The increase in illnesses, symptoms and pathologies becomes
most apparent after the age of 65 years.1 However, the elderly are
not a uniform group. The ‘old’ elderly (those over 75 years) show
greater age-related changes in drug disposition and response
than the ‘young’ elderly. The sick elderly patient may tolerate and
respond differently to medications than the well elderly person.1
What is a cough?
A cough is a natural reflex reaction to an irritation in the air
passages and lungs. Air is drawn into the air passages with
the glottis open. The inhaled air is blown out against the closed
glottis, which, as the pressure builds, suddenly opens, expelling the air at speeds of up to 960 kilometres per hour. This expels harmful substances from the respiratory tract.2 Coughing
helps the body to rid itself of excess mucus and other irritants.
The physical efforts of persistent coughing can increase irritation
of the air passages and cause distress to the patient.2 Each
cough occurs through the irritation of cough receptors. These
receptors may be found not only in the upper and lower respiratory tracts, but also in the pericardium, oesophagus, diaphragm
and stomach. Chemical receptors are sensitive to acid, heat and
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capsaicin-like compounds.3 Triggers such as touch or displacement can stimulate mechanical receptors.3 Some receptors such
as those found in the larynx and trachea, respond to both chemical and mechanical stimuli.3 Impulses from stimulated receptors are transmitted to a “cough centre” in the brain. A signal is
generated to the expiratory muscles to cause the cough.3
Causes of cough
Cough may be classified by duration of the cough. Acute cough
lasts for less than three weeks and is commonly due to an acute
respiratory infection. Coughing that has lasted for more than 3
weeks, but less than eight weeks, is classed as sub-acute, while a
cough that has been present for more than eight weeks is known as
a chronic cough.3 The causes of cough are summarised in Table I.
Acute cough:
• Choking – sucking or inhaling liquid or solid particles into
the airways leads to intense coughing. This coughing bout may
cause discomfort but generally does not require medical attention once the foreign matter is expelled, unless some of the
material is aspirated. Aspiration requires medical treatment to
prevent infection and lung damage. If the foreign body is not expelled and occludes the airway, coughing may cease, followed
by cyanosis and unconsciousness. This is a medical emergency.
• Acute respiratory tract infection – Bacterial or viral infections of the respiratory tract such as acute bronchitis, sinusitis,
laryngitis, pharyngitis or pneumonia may produce increased
mucus and inflammation, which causes coughing. These conditions should clear within two to three weeks with appropriate
treatment. The cough may continue after the acute symptoms of
the infection have disappeared due to irritability of the airways.3,5
Chronic cough:
• Postnasal drip – cough due to postnasal drip may also be
referred to as upper airway cough syndrome.3 This is one of the
most common causes of sub-acute and chronic cough. The main
reasons for a postnasal drip include allergic rhinitis, perennial
non-allergic rhinitis, vasomotor rhinitis, acute naso-pharyngitis
and sinusitis.3 Increased secretions in the upper airway stimu-
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late cough receptors in the laryngeal mucosa. Symptoms may
include nasal discharge, a sensation of fluid dripping in the back
of the throat and frequent throat clearing. A “silent” postnasal drip
causes no symptoms other than a cough. Symptoms and signs of
postnasal drip are non-specific, and it is the response to treatment
that confirms the diagnosis.3 When patients have no other obvious
cause for a cough, treatment for postnasal drip should be considered. Allergy-related coughs may be non-productive and worse at
night. However, other symptoms such as nasal congestion, itching
of the eyes, nose or mouth are usually present.7
•Asthma – is considered to be one of the leading causes of
persistent cough in adults and the most common cause of chronic
cough in children.3 Asthma is commonly characterised by coughing, wheezing, shortness of breath (dyspnoea) and chest tightness.7 However, asthma may present solely as a non-productive
cough. This is known as cough-variant asthma, and can progress
to include wheezing and shortness of breath.3 Asthma-related
cough may be seasonal, may follow a respiratory infection, or may
worsen with exposure to cold, dry air or certain allergens.3
•Gastro-oesophageal reflux disease (GORD) – is one of
the most common causes of chronic cough.3 Many patients with
cough due to acid reflux complain of heartburn or a sour taste in the
mouth, but these symptoms are not present in all patients for whom
cough is related to acid reflux.3,5 Cough associated with GORD is
potentially due to the following: stimulation of receptors in the larynx, aspiration of stomach contents, leading to irritation of receptors
in the lower respiratory tract, or reflux of acid into the oesophagus.3
Table I: Causes of cough
Choking
Respiratory tract infections:
• Acute bronchitis
• Laryngitis
• Pharyngitis
• Tonsillitis
• Sinusitis
• Pneumonia
Postnasal drip:
• Allergic
• Perennial non-allergic
• Vasomotor rhinitis
• Sinusitis
Asthma
Gastro-oesophageal Reflux Disease (GORD)
Chronic bronchitis
Lung cancer
Smoking
Eosinophilic bronchitis
ACE inhibitors#
Bronchiectasis
Tuberculosis (TB)
Heart Failure
The side effect profiles of many other medications also list cough as a possible adverse effect,
for example non-steroidal anti-inflammatories (NSAIDs) and beta-blockers.7 However, these
are not often associated with chronic cough.
#
Note:
Cough can also be caused by other factors such as pertussis, croup (in children) and vocal
cord paralysis. In the elderly, swallowing dysfunction may lead to chronic cough.3
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Cough due to acid reflux may be exacerbated when lying down.7
•Chronic bronchitis – is defined as the presence of a cough
and the production of sputum on most days over a three-month
period for at least two consecutive years.3 Almost all patients are
smokers, although a few have airway inflammation due to chronic
exposure to other fumes and dusts.3 The cough is usually productive, producing a clear or white sputum.3 The term COPD (chronic
obstructive pulmonary disease) is often used interchangeably with
the terms chronic bronchitis and/or emphysema because chronic
bronchitis and emphysema are the most common forms of COPD.6
•Lung cancer – should be considered as a possible cause
of a new cough or a change in chronic “smoker’s cough”.3 The
cough may produce blood-streaked sputum.7
•Smoking – many long-term smokers develop a chronic
cough. This is typically a loud hacking cough, often resulting in the
expiration of phlegm.7 Most smokers accept cough as a side effect
of smoking and do not seek medical attention.3 A change in the
nature of the cough, or in the colour of the sputum produced may
indicate increased damage to the lungs or possible malignancy.7
•Eosinophilic bronchitis – presents as a non-productive
cough caused by inflammation in the airways. Patients demonstrate atopic tendencies (a tendency to produce large amounts of
antibodies), with elevated sputum eosinophils and active airway
inflammation.3 Patients with eosinophilic bronchitis may be at increased risk of asthma, and most asthmatics have this condition.3
•Angiotensin converting enzyme (ACE) inhibitors – are
commonly used to treat hypertension. A dry, hacking non-productive cough is a well-recognised side effect of these medications.3
Onset of cough may occur within a few hours of the initial dose,
or may develop after several months of therapy.3 If a cough is
suspected to be due to an ACE inhibitor, does not resolve within
four weeks, then a change in antihypertensive therapy may be indicated.7 ACE-inhibitor induced cough tends to resolve one to four
days after discontinuing treatment, but may take up to four weeks
to disappear completely.3
•Bronchiectasis – results from severe, repeated, or persistent airway inflammation leading to progressive airway damage.3
Bronchi become dilated as a result of obstruction, poor mucus
clearance, pooling of secretions, and chronic lower respiratory
tract infections.3 Some patients may have non-productive cough,
but most produce chronic mucopurulent sputum.3,7 Lung examination often reveals abnormal lung sounds.3
•Tuberculosis (TB) – is characterised by its slow onset
and initially mild symptoms. The cough becomes chronic and
sputum production varies from mild to severe. Sputum is often
blood- streaked.7
•Heart failure – is characterised by its slow progression.
The initial symptoms are shortness of breath and dyspnoea at
night. Later the patient may develop a productive, frothy cough,
which may be pink-tinged, indicative of ventricular failure.7
Types of cough
Coughs are often described as wet or dry. A wet or productive cough is one in which sputum or mucus is produced. The
mucus may be loose so that it can be swallowed or spat out, or
may be described as ‘chesty’, in that it is retained in the lungs.
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When mucus is coughed up it may be examined in order to
help in the differential diagnosis of cough:
•• Clear or white sputum is often present in chronic bronchitis.3
•• A greenish or yellow appearance to the mucus is often indicative of an infection such as acute bronchitis or pneumonia.3
•• Blood-stained sputum - the patient should always be referred to a doctor if blood is present in the mucus or sputum
as this may be indicative of tuberculosis or cancer.7
A dry or non-productive cough is often described as tight, tickly
or irritating. A dry cough may be caused by air pollution, dust or
a change in temperature, as well as by various medical conditions, including asthma.7 See Table II.
Table II: Types of cough
Wet Cough
Respiratory tract infections:
• Laryngitis
• Sinusitis
• Pharyngitis
• Tonsillitis
• Pneumonia
Postnasal drip
Chronic bronchitis
Lung cancer
Smoking
Bronchiectasis
TB
Heart failure
Dry Cough
Asthma
GORD
ACE inhibitors
Allergic rhinitis
Acute bronchitis
Eosinophilic bronchitis
Considerations in the elderly
Different causes for the cough
As many elderly patients may present with pre-existing conditions, it is important to enquire about their medical history.
Many of the common causes of cough are associated with
medical conditions affecting older people e.g. chronic bronchitis, hypertension treated with ACE inhibitors, and heart failure.
Higher risk for drug interactions and adverse effects
Due to the increased incidence of illnesses, the associated
increased use of medicines, both prescribed and over-thecounter, increases the potential for drug-drug interactions,
drug-disease interactions and medication adverse effects.1
Symptom presentation
The presentation of illness may change with age. Adverse
effects caused by medications may not be recognised e.g.
ACE-inhibitor cough.1
Aging-related alterations
Aging is associated with an increase in body fat, a reduction in
body water, changes in gastric acidity and changes in hepatic
and renal clearance. These changes may require changes in
doses of medications or the use of a different medication.1
In the elderly, persistent coughing may more easily lead to exhaustion, insomnia, dizziness and musculoskeletal pain. A bout of
coughing may result in urinary incontinence, especially in women.3
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Another potentially serious complication of chronic cough in an
elderly patient is cough-induced rib fractures. Women with decreased bone density are at the greatest risk of this complication.3
Treatment of cough
Various questions must be asked of all patients seeking treatment for cough:
•• Who is the patient? Adult or child?
•• What type of cough is it? Wet or dry?
•• When did the cough start?
•• Is there any mucus? What colour is it?
•• Are there any other medical conditions present?
•• Is the patient on any medication?
•• Does the patient smoke?
Once the various signs and symptoms have been evaluated,
medication use and other medical conditions taken into consideration, a treatment course may be decided. A doctor must be
consulted if any ‘red flag’ symptoms are present (See Table III).
Table III: Red flag symptoms of cough4
Discoloured mucus – yellow, green, rusty brown, blood-stained or
pink
Foul smelling mucus
Chest pain
Heartburn
Shortness of breath or wheezing
Recurrent night-time cough
Whooping cough or croup
Worsening smoker’s cough
Sudden weight loss
Fever
Cough lasting more than 3 weeks
Conclusion
Elderly people are a unique group with unique treatment problems as they frequently have pre-existing conditions that are
being treated. No medication need be withheld on the grounds
of age alone, providing that the indications exist and that all
other factors have been considered.1
When a patient presents with a cough a thorough history should
be taken to determine whether the problem can be dealt with
over-the-counter, or whether further examination is necessary. A
doctor must evaluate any cough that has been present for more
than two to three weeks or that produces discoloured mucus.r
References
1.Gibbon CJ. (ed) South African Medicines Formulary (SAMF) 8TH ed. Health
and Medical Publishing Group of the South African Medical Association.
2.Macpherson G (ed). Black’s Student Medical Dictionary. A&C Black Publishers Limited.
3.Silvestri RC. Weinberger SE. Evaluation of sub acute and chronic cough in
adults. UpToDate.com. (Accessed 25 February 2010).
4.Pillinger J. Coughing. www.netdoctor.co.uk (Accessed 25 February 2010).
5.Silvestri RC. Weinberger SE. Patient Information: Chronic cough in adults.
September 2009. http://www.utdol.com/patients/ . (Accessed 2 March 2010).
6.Rennard SI. Patient information: Chronic obstructive pulmonary disease
(COPD). June 2009. http://www.utdol.com/patients/ (Accessed 2 March 2010).
7.Truter I. 2007. Cough. SA Pharmaceutical Journal. 74 (4 May):20-27.
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