Norton Infectious Diseases Institute researchers report pneumonia may increase long-term risks for heart disease, diabetes, and decreases in life expectancy.

Published: January 7, 2026 | Updated: January 16, 2026

Reviewed by Anupama Raghuram, M.D., and Julio A. Ramirez, M.D.

Norton Infectious Diseases Institute researchers are challenging the traditional view of pneumonia as a self- limited acute lung infection, revealing that the disease may be associated with chronic complications affecting multiple organ systems for years after initial diagnosis.

Julio A. Ramirez, M.D., and Anupama Raghuram, M.D., infectious diseases physicians with Norton Infectious Diseases Institute, are exploring the concept that pneumonia’s lasting impact may extend far beyond the respiratory system. Their initial findings suggest the infection can decrease life expectancy and increase risks for cardiovascular disease, diabetes and dementia years after hospital discharge.

“We have data on the impact of pneumonia,” Dr. Ramirez said. “For a significant number of patients, pneumonia decreases life expectancy. Even if your physician has released you from care, you are at risk of developing noninfectious issues.”

The research reveals that patients who survive pneumonia face elevated risks for pulmonary issues, cardiac issues and myocardial infarction one to two years post-diagnosis. Some patients may experience decreased life expectancy of one to three years following their pneumonia diagnosis.

Long-term health effects of pneumonia

“Originally, we thought after one or maybe two weeks after diagnosis and treatment, you are cured. End of the story,” Dr. Ramirez said. “Now we are learning that the entire concept needs to change, because we’re seeing all these effects long after the patient leaves the hospital or treatment is discontinued.”

Pneumonia can affect the body for years after infection. Issues may include:

• Lung damage: Severe pneumonia can lead to fibrosis, which makes it harder for the lungs to function properly. 
• Reduced lung function: Even without scarring, some people, especially older adults, may experience reduced lung capacity and shortness of breath for months after recovering.
• Respiratory conditions: In some cases, pneumonia can increase the risk of developing chronic conditions like asthma or chronic obstructive pulmonary disease later in life.
• Other complications: Some individuals may develop a lung abscess or pleural effusion that requires further treatment. 
• General health impact: Long-term effects also can include a worsening of existing heart and blood vessel diseases, depression or a reduced ability to exercise.

Pneumonia effect on gut health

The Norton Infectious Diseases Institute team is investigating whether pneumonia’s long-term consequences extend to the gut microbiome. In collaboration with Shirish Barve, Ph.D, Norton Infectious Diseases Institute researchers are exploring potential connections between pneumonia and chronic systemic inflammation.

The research challenges the historical assumption that pneumonia represents only an acute health concern. Instead, the team is documenting how the disease may produce chronic issues affecting multiple organ systems throughout the body.

Their findings could have significant implications for post-pneumonia patient care and long-term health monitoring, suggesting that patients may require extended follow-up beyond traditional acute care protocols.