Chronic Cough

What is Cough?

Cough is one of the most common complaints for clinic visits accounting for as many as 30 million visits to the doctor per year. Cough in general, is an innate protective reflex characterized by sudden expulsion of air from breathing passage. A chronic cough is when a cough lasts longer than 8 weeks in adults or 4 weeks in children.

Causes

There are various conditions that can result in a chronic cough. Some of the most important causes of chronic cough are mentioned below:

• Upper Airway Cough Syndrome (UACS): It is the most common cause of chronic cough and includes all nasopharyngeal conditions (including allergic rhinitis, rhinosinusitis, and laryngopharyngitis) that may be associated with post-nasal drip and a sensation of irritation of secretions in the back of the throat and the upper airways that present with a cough as the only symptom.
• Cough-Variant Asthma (C-VA): Asthma can present with only a cough.
• Non-asthmatic eosinophilic bronchitis (NAEB): NAEB presents with an eosinophilic airway inflammation like asthma, but there is no airflow limitation on spirometry. A chest x-ray is usually normal. This condition is often difficult to diagnose.
• Gastroesophageal Reflux Disease(GERD): Reflux can trigger cough by a direct effect of acid on the proximal part of the oesophagus and the laryngopharyngeal areas or by indirect vagal stimulation through the effect of gastric contents on the distal part of the oesophagus.
• Cough Hypersensitivity Syndrome (CHS): Cough hypersensitivity syndrome is defined as ףtroublesome coughing triggered by a low level of thermal, mechanical, or chemical exposure.פ Patients develop a cough in an exaggerated response to stimuli that would not otherwise trigger cough. A chronic cough is seen with UACS, asthma, and reflux may be induced by the development of cough hypersensitivity.
• Chronic bronchitis is characterised by a cough that has been present for longer than 3 months consecutively over 2 years. Cough occurs due to excessive mucous secretions causing mucous plugging of the airways.
• Post-infectious cough can occur during recovery from a pulmonary infection.
• Interstitial lung diseases are a large group of disorders which cause progressive scarring and hardening of lung tissue occurring due to long-term exposure to various hazardous materials, such as asbestos, silicone, coal dust, radiation, or heavy metals.
• Obstructive sleep apnoea is characterized by a partial or complete obstruction of the airway transiently during sleep occuring as a result of lax musculature in the pharynx or due to the increased weight of the neck collapsing the pharynx in obese people. This increase in airway resistance causes a reflexive diaphragmatic and chest muscle spasm and cough to open the obstructed airway and pull air into the lungs.
• Chronic sinusitis induced cough can result from prolonged inflammation and irritation of the sinus and nasal mucosa with purulent discharge secondary to a bacterial pathogen.
• Psychosomatic cough is the act of coughing as a habit rather than as part of a disease process.

Diagnosis

Diagnosis is done clinically, but some cases may require an X ray chest, HRCT and sputum examination among other tests specific for the cause.

Management

The treatment depends on the underlying cause. It is recommended to maintain good hygiene, wash hands before eating, cover mouth and nose with handkerchief while coughing, drink plenty of fluids, warm water gargles etc., to prevent infection and to speed up recovery. Cessation of smoking also helps in the treatment.

Warning: Above information provided is an overview of the disease, we strongly recommend a doctor's consultation to prevent further advancement of disease and/or development of complications.

Disclaimer: The information provided herein on request, is not to be taken as a replacement for medical advice or diagnosis or treatment of any medical condition. DO NOT SELF MEDICATE. PLEASE CONSULT YOUR PHYSICIAN FOR PROPER DIAGNOSIS AND PRESCRIPTION.