Excerpts from "Dysphagia" by Nam-Jong Paik, MD, PhD update for E-medicine.com August 19, 2004

Malnutrition is a risk factor for pneumonia because:

  1. it renders the person susceptible to altered colonization in the oropharynx and reduced resistance to infection by depressing the immune system;
  2. it may lead to lethargy, weakness, and reduced alertness, all of which may increase the probability of aspiration;
  3. it may reduce the strength of cough and mechanical clearance in the lungs.

Dehydration: Dysphagia could potentially lead to dehydration. Conversely, dehydration also may be a risk factor for pneumonia because:

  1. it decreases salivary flow, which promotes altered colonization of the oropharynx;
  2. it may lead to lethargy and mental confusion and increased aspiration;
  3. it makes the person susceptible to infection by depressing the immune system.