Introduction

• Lung function gradually declines after age 20.
• In the absence of lung insults (eg, smoking, exposure to environmental toxins or previous lung infections), most elderly people have enough lung reserve to avoid any breathing symptoms.
• However, in smokers/ former smokers and those exposed to environmental toxins, injury due to inflammation is superimposed on and accelerates the effects of aging, resulting in dyspnea (or difficulty in breathing).
• Other serious risk factors for lung symptoms in the elderly include deconditioning, obesity and heart disease.

Sign & Symptoms

• As people age, the muscles used in breathing such as the diaphragm, tend to weaken by up to 25% with aging. Also, slightly less oxygen is absorbed from air that is breathed in.
• In people who do not smoke or have a lung disorder, the muscles of breathing and the lungs continue to function well enough to meet the needs of the body during ordinary daily activities.
• However, in the presence of a disorder that requires sustained increases in breathing effort eg. lung infection, may lead to lower oxygen and higher carbon dioxide levels. This increase the risk for need of mechanical assisted ventilation.
• These changes may make exercising vigorously, for example, running or biking more difficult.
• Older people may also have difficulty breathing at high altitudes due to thinner oxygen content.
• In addition, the lungs become less able to fight infection because the cells that sweep debris out of the airways decline with aging. The cough reflex which helps to clear the lungs, tends to be weaker with age and increase the risk of lung infection.

Complications

• Difficulties with swallowing and impaired esophageal (the tube through which food passes from the mouth to the stomach) motility occur more often in the elderly and increase risk of aspiration (or food goes into the lung).
• More than 70% of elderly patients with community-acquired pneumonia develop a blunted cough reflex (compared with only 10% of age-matched controls), probably due to accompanying decreased oxygeration of blood, drug-induced sedation and neurologic disorders.