backgroundThere is a paucity of contemporary national estimates for

methodsWe analyzed the 2017 National Inpatient Sample (NIS) to determine the population-based rates of CDI hospitalizations, characteristics of hospitalizations with CDI, and the rates of comorbidities associated with CDI hospitalizations.

resultsThere were 329,460 CDI-related hospitalizations in 2017 (almost 1% of all hospitalizations). The average age for patients admitted with CDI as a principal or secondary diagnosis was 64.7 years (almost 20 years older when compared with all other hospitalizations). Patients 85 years and older had the highest rate of CDI hospitalizations (716 per 100,000 hospitalizations), and patients less than 18 years of age had the lowest rate (12 per 100,000 hospitalizations). There was a progressive increase in the CDI hospitalization rates with each successive age group. The hospitalization rates were higher in females (114 per 100,000 hospitalizations) than males (88 per 100,000 hospitalizations). The CDI hospitalization rate was highest in the Northeast (109 per 100,000 hospitalizations) and lowest in the West (84 per 100,000 hospitalizations). Fluid and electrolyte disturbance (63.3%) and renal failure (33.4%) were the two most common comorbidities associated with CDI hospitalizations. When CDI is a secondary diagnosis, major loss of function, extreme likelihood of dying, septicemia, and septic shock were more common in comparison to CDI as a principal diagnosis.

conclusionsCDI hospitalization rates were highest in the elderly over 85 years old and declined with successive decreases in age. Women had higher CDI hospitalization rates than men, and fluid and electrolyte disturbances and renal failure were the most common comorbid conditions. The presence of CDI as a comorbid condition at the time of hospitalization for other principal diagnoses or development of CDI during a hospitalization for other principal diagnoses significantly increases the risk of in-hospital morbidity and mortality.