Geriatrics:Aging changes in Lungs

The lungs are effected by changes that occur in many other body systems, such as the cardiovascular, nervous and musculoskeletal systems. Changes in lung function are one of the best predictors of mortality. Most of the normal respiratory changes with age are of little functional significance in healthy older adults. However, they do reduce reserve capacity and increase vulnerability to respiratory disease.

Lung Capacity with Aging

As we age, the lungs become stiffer, respiratory muscle strength and endurance diminishes, and the chest wall becomes more rigid. Total lung capacity is relatively constant across the life span but vital capacity (the volume of air that can be forcibly exhaled) decreases because our residual volume increases (the amount of air remaining in the lungs after maximum expiration). At age twenty, about twenty percent of our total lung capacity is residual air; at age sixty the residual air volume increases to about 35 percent.

Lung Capacity Decrease

In the normal aging lung, alveolar surface area decreases by up to 20 percent which reduces our maximal oxygen uptake (the volume of air that can be moved in and out by forced voluntary breathing) by as much as 55% by age 85. Thus, over time our exercise capacity declines because we have less "reserve". In addition, the alveoli of older adults tend to collapse sooner on expiration than in younger peoples. This tendency is exacerbated by reduced mobility, illness, and hypoventilation and increases the risk for respiratory diseases such as atelectasis.

The BLUE represents the amount of air inhaled at any time by a person.

The RED represents the Lungs.

The PINK (below the Lungs) represents the diaphram.

Older adults are less efficient in monitoring and controlling breathing. Older adults may be at greater risk for dying from acute lung problems if they seek medical care later rather than sooner.

Risk for Infection Increase

In addition, the number of cilia decline in number as we grow older. Cilia protect against infection by clearing irritants and obstruction. At the same time, the number of mucus producing cells may increase resulting in mucus clogging your airways. These changes make older adults more vulnerable to respiratory infections. These changes make older adults less efficient in monitoring and controlling breathing. For example, they are less sensitive to hypoxia and less able to recognize acute bronchoconstriction. Although the causes are not well understood, the implications are clear. Older adults may be at greater risk for mortality from acute respiratory problems if they are less aware of respiratory symptoms and seek medical care later rather than sooner.