A risk factor is something that increases your chance of getting a disease or condition.
It is possible to develop pneumonia with or without the risk factors listed below. However, the more risk factors you have, the greater your chance of developing pneumonia. If you have a number of risk factors, ask your doctor what you can do to reduce your risk.
Smoking and Second-hand Smoke
People who smoke have a much higher risk of developing pneumonia. If you stop smoking, your risk will gradually return to normal. However, this may take as long as 10 years.
You are also at risk for pneumonia if you are regularly exposed to second-hand smoke. For example, children in households where the parents smoke have higher rates of pneumonia than do children in smoke-free households.
The risk of pneumonia is increased among people living in crowded conditions, such as:
People who are hospitalized have a much higher risk of developing pneumonia than do non-hospitalized individuals. This risk is even higher for people who have recently undergone major surgery or who are on ventilators. Other medical conditions that can increase your risk of developing pneumonia include:
Children have a higher risk of developing pneumonia if they have:
Pneumonia is more common among certain age groups:
A number of genetic disorders can predispose you to pneumonia, such as:
Occupational exposure to toxic chemical fumes and/or smoke can weaken your lung’s defenses. This can increase your vulnerability to pneumonia germs.
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Risk factors. National Heart, Lung, and Blood website. Available at: http://www.nhlbi.nih.gov/health/health-topics/topics/pnu/atrisk. Updated September 26, 2016. Accessed November 10, 2016.
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2/3/2015 DynaMed Plus Systematic Literature Surveillance http://www.dynamed.com/topics/dmp~AN~T115170/Community-acquired-pneumonia-in-adults: Rantala A, Jaakkola JJ, Jaakkola MS. Respiratory infections in adults with atopic disease and IgE antibodies to common aeroallergens. PLoS One. 2013;8(7):e68582.
Last reviewed November 2016 by David L. Horn, MD
Please be aware that this information is provided to supplement the care provided by your physician. It is neither intended nor implied to be a substitute for professional medical advice. CALL YOUR HEALTHCARE PROVIDER IMMEDIATELY IF YOU THINK YOU MAY HAVE A MEDICAL EMERGENCY. Always seek the advice of your physician or other qualified health provider prior to starting any new treatment or with any questions you may have regarding a medical condition.