Reducing Mortality, Economic Burden of Clostridioides difficile Infection in Older Adults

Clostridioides difficile infection (CDI) is the most common health care–associated infection in the United States, and it s associated with high mortality, cost, and clinical burden, especially in older patients. Many patients who experience a CDI suffer recurrence, which can further add to health care utilization.

Overall, total US costs related to CDI are estimated at $2.8 billion annually, although patients who experience recurrence have higher per-patient costs than those who do not.

An article in press in Journal of the American Medical Directors Association estimated the mortality, cost, and health care resource utilization (HRU) for Medicare beneficiaries who experienced CDIs from 2009 through 2017. This included patients who experienced a primary CDI episode or recurrent infection, and patients were stratified by survival to identify associations between CDI outcomes and death.

The retrospective cohort study included claims data from 497,489 Medicare beneficiaries aged 65 or older who had CDIs, 30.5% of whom experienced recurrent CDI. During the 12-month follow-up, 186,996 patients (37.6%) with a primary CDI survived, and 158,897 patients with primary CDIs (31.9%) died. For those with recurrent CDIs, 97,738 patients (19.6%) survived, and 53,858 patients (10.8%) died during the follow-up period.

The CDI-associated mortality rate for patients who died during follow-up was 2.7% for those with primary CDI vs 25.4% for those with recurrent CDI—a nearly 10-fold difference. Most deaths happened quickly, with half or more of the deaths in each cohort occurring by 16 weeks after the index CDI.

The soonest deaths were those that were not associated with CDI but occurred after primary infection, and these likely could be attributed to an illness that preceded the CDI. In the other cohorts, there were similar early death patterns that were less pronounced. CDI-associated mortality rates also climbed with the number of recurrences.

Patients who died were more likely to be older, especially 85 years or older, and have comorbidities at baseline compared with patients who survived. Decedents were also more likely to have congestive heart failure, chronic obstructive pulmonary disease, diabetes without complications, peripheral vascular disease, and renal disease.

In the 6 months before index CDI, survivors had lesser utilization of acute hospitalizations and post-acute care stays, and they were generally hospitalized for 1 less day than patients who died during follow-up.

The total medical costs for decedents were an estimated $63,014 to $70,304 during the 6-month baseline period vs $40,210 to $49,223 for survivors. Overall, total costs were 303% higher in patients with primary CDI and 297% higher in those with recurrent CDI who died during follow-up.

When adjusted for comorbidities, decedents had higher hospitalization rates. Those with primary CDI had an odds ratio (OR) of 1.83 compared with 2.58 for those with recurrent CDIs (P < .001). Those with recurrent CDI who died utilized the intensive care unit more (OR, 2.34; P < .001), and decedents had 3.1- and 2.6-day longer lengths of stay for primary and recurrent CDI, respectively.

Overall, the study found that mortality rates were much higher in older Medicare beneficiaries who had recurrent CDI vs those who only had primary CDI and that the risk of death was higher with more recurrences.

The study’s strengths include the large cohort size and longitudinal nature of the HRU claims. One limitation is the generalizability of the data pulled from Medicare claims, which do not include younger patients or those with private insurance, Medicaid only, or insurance through Veterans Affairs. The authors note, however, that studies of CDI mortality in Veterans Affairs facilities have shown similar results regarding mortality.

“Clinicians should be particularly attentive to prevention, identification, and appropriate treatment of CDI in older adults,” study authors concluded. “Better treatments to reduce primary C diff infection and recurrences in this vulnerable population can lower both mortality and economic burden.”

Reference

Feuerstadt P, Nelson W, Drozd E, et al. Mortality, health care use, and costs of Clostridioides difficile infections in older adults. J Am Med Dir Assoc. Published online March 11, 2022. doi:10.1016/j.jamda.2022.01.075