Researchers Identify Clear Trends for C Diff Hospitalizations

Females and older patients had higher rates of hospitalizations with CDI than males and younger patients.

National estimates of clostridium difficile infection (CDI) infection hospitalizations by demographics and patient comorbidities are considered insufficient in the US.

A team, led by Dhanshree Solanki, Edward J Bloustein School of Planning & Public Policy, identified hospitalization rates for C. diff by age group, sex, and region, as well as for patient comorbidity in the US.

In the study, the researchers analyzed the 2017 National Inpatient Sample (NIS) and identified 329,460 CDI-related hospitalizations, accounting for nearly 1% of all hospitalizations.

However, there were some stark differences found between CDI hospitalized patient characteristics and the general population of hospitalized individuals.

CDI hospitalization rates were highest in the elderly over 85 years old and declined with successive decreases in age,” the authors wrote. “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.”

Age, Sex, and Region

The average CDI patient was admitted to the hospital at 64.7 years old, which is approximately 20 years older than the average age at admission of all other hospitalizations.

In addition, the highest rate of CDI hospitalizations—716 per 100,000 hospitalizations—was in patients at least 85 years old.

The inverse of that relationship was also true as those 18 years and younger had the lowest rate of hospitalizations at 12 per 100,000 hospitalizations.

“There was a progressive increase in the CDI hospitalization rates with each successive age group,” the authors wrote.

There were also trends in CDI hospitalizations based on sex and region.

Female patients had a higher rate of hospitalizations—114 per 100,000 hospitalizations—than males—88 per 100,000 hospitalizations.

In addition, the hospitalization rate for c diff was highest in the Northeast—109 per 100,000 hospitalizations—and lowest in the West—84 per 100,000 hospitalizations.


Some of the common comorbidities for CDI patients included fluid and electrolyte disturbance (63.3%) and renal failure (33.4%), while 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.

Hope for the Future

There is some hope that CDI hospitalization rates might see a drop, largely because of the mitigation measures hospitals have put in place to try to combat the spread of COVID-19.

Researchers recently found in a retrospective cohort study of 9 Massachusetts hospitals 97 (24.9%) patients who were tested for CDI, with a mean age of 62.4 years old. Of this group, 5 (5.2%) patients tested positive for CDI, which was lower than the overall inpatient CDI-positive rate in 2019 (n = 280; 9.8% of tests performed). However, this was not statistically significant (= 0.16).

The study, Clostridium difficile Infection Hospitalizations in the United States: Insights From the 2017 National Inpatient Sample,” was published online in Gastroenterology Research.