Sinusitis

Description

Alternative Names

Risk Factors

Sinusitis is one of the most common diseases in the United States. According to the National Institute of Allergies and Infectious Diseases (NIAID), it affects an estimate 37 million Americans each year. Along with asthma, allergies, and other upper respiratory tract infections, sinusitis has increased dramatically. A 2000 study suggested that 66 million Americans report some type of sinus problem during the year. The causes for the increases in upper respiratory problems are under intense debate. However, a recent report in the March 2004 issue of the Archives of Otolaryngology Head and Neck Surgery suggests just the opposite that sinusitis may not be as common as previously reported and that accounts that rely solely on patient self-reporting may be exaggerated.

General Risk Factors for Sinusitis after a Cold

Everyone gets viral colds and flu, and most people develop symptoms in the upper respiratory tract (air passages in the head and neck) at some point. Over 85% of people with colds have inflamed sinuses. These inflammations are typically brief and mild, however, and only between 0.5% and 10% of people with colds develop true sinusitis. (One study suggested that nose blowing during a cold may transmit bacteria back into the sinuses and increase the risk for sinusitis.) Studies suggest that the following population groups have higher risks for sinusitis:

• The very young and the very old are at higher risk for more serious upper respiratory tract infections and for complications from them.
• Women appear to be at higher risk than men.
• People living in the Midwest and South have a higher incidence of sinusitis than those in the Northeast and West.
• People in higher income and educational groups appear to have a greater risk than those in lower groups.
• Caucasian and African Americans have a higher rate than Hispanic Americans.

Young Children and Sinusitis

Before the immune system matures, all infants are susceptible to respiratory infections, with a possible frequency of one cold every one or two months. Young children are prone to colds and may have eight to 12 bouts every year. Smaller nasal and sinus passages also make children more vulnerable to upper respiratory tract infections than older children and adults. Nevertheless, true sinusitis is very rare in children under eight or nine. Some experts believe it is greatly overdiagnosed in this population.

The Elderly and Sinusitis

The elderly are at specific risk for sinusitis. Their nasal passages tend to dry out with age. In addition, the cartilage supporting the nasal passages weakens causing airflow changes. They also have diminished cough and gag reflexes and faltering immune systems and are at greater risk for serious respiratory infections than are young and middle-aged adults.

People with Asthma, Allergies, or Both

People with asthma, allergies or both are at higher risk for non-infectious inflammation in the sinuses. The risk for sinusitis is higher in patients with severe asthma. People with a combination of polyps in the nose, asthma, and sensitivity to aspirin (called Samter's or ASA triad) are specifically at very high risk for chronic or recurrent acute sinusitis.

Hospitalization

Hospitalized patients are at higher risk for sinusitis, particularly the following:

• Patients with head injuries.
• Patients with conditions requiring insertion of tubes through the nose.
• Patients taking antibiotics or steroids.
• People whose breathing is aided by mechanical ventilators may have a significantly higher risk for maxillary sinusitis. In fact, treating sinusitis in such patients may significantly reduce the risk for ventilator-associated pneumonia.

People with High-Risk Medical Conditions Affecting the Sinuses

A number of medical conditions put people at risk for chronic sinusitis. They include the following:

• Diabetes.
• AIDS and other disorders of the immune system predispose the patient to sinusitis, with fungal infections being a particular risk.
• Pregnancy is sometimes associated with congestion and symptoms of sinusitis, although the condition is temporary.
• Hypothyroidism is associated with congestion that clears up when the condition is treated.
• Cystic fibrosis, a genetic disorder in which the mucus is very thick and builds up.
• Kartagener's syndrome, a very rare genetic disorder in which the major organs in the body are reversed, and the body's cilia (hair-like projections on many body tissues that help to move mucus and other fluids) are motionless.
• Wegener's granulomatosis, a serious but very rare illness that causes long-term swelling and tumor-like masses in air passages.

Miscellaneous Risk Factors

Dental Problems. Anaerobic bacteria are associated with infections from dental problems or procedures, which precipitate about 10% of cases of sinusitis.

Changes in Atmospheric Pressure. People who experience changes in atmospheric pressure, such as while flying, climbing to high altitudes, or swimming, risk sinus blockage and therefore an increased chance of developing sinusitis. (Swimming increases the risk for sinusitis for other reasons, as well.)

Cigarette Smoke and Other Air Pollutants. Air pollution from industrial chemicals, cigarette smoke, or other pollutants can damage the cilia responsible for moving mucus through the sinuses. Whether air pollution is an important cause of sinusitis and, if so, which pollutants are critical factors is still not clear. Cigarette smoke, for example, poses a small but increased risk for sinusitis in adults. Second-hand smoke does not appear to have any significant effect on adult sinuses, although it does seem to pose a risk for sinusitis in children.