An evaluation of current therapeutic strategies for elderly patients with C. difficile.
Tomefa Asempa, PharmD
Since elderly adults are at a disproportionately higher risk for Clostridium difficile (C. difficile) infection, a new review is calling for expanded treatment strategies for the population.
Researchers from Hartford Hospital in Connecticut, reviewed the epidemiology of C. difficile and its risk factors in order to outline the current and emerging therapeutic options for geriatric patients. The study authors cited a 2015 Centers for Disease Control and Prevention (CDC) report which said that 2 out of 3 (70—80%) health care associated C. difficile infections happens in patients 65 years or older.
This population is especially vulnerable, the investigators said, and reducing the incidence is vital due to the “significant morbidity, mortality, and financial cost associated with this infection.” Additionally, national mortality records demonstrated that C. difficile linked deaths in the US rose from 5.7 deaths per million in 1999 to 23.7 deaths per million in 2004.
Beyond advanced age, the study authors outlined the risks for C. difficile infection in the geriatric population: increased exposure to antimicrobial therapy for other infections, exposure to C. difficile spores, and the host immune response.
Successfully treating an infection implies the elimination of symptoms plus the prevention of recurrent treatment, and can be achieved through supportive care with fluid and electrolyte replacement, discontinuing the precipitating of antimicrobials when appropriate, and initializing effective anti C. difficile therapy.
“A greater awareness of the risk factors for C. difficile infection will allow physicians to adopt best practices in terms of antimicrobial stewardship and C. difficile infection treatment, i.e. utilize therapeutic agents based on patient severity and most importantly the patient’s risk of C. difficile infection recurrence,” Dr. Tomefa Asempa told MD Magazine.
According to the information the study authors reviewed, older adults may be best treated with vancomycin as opposed to metronidazole.
Metronidazole seemed to demonstrate higher levels of recurrence and treatment failure in older adults compared to vancomycin. Despite its high drug acquisition cost, fidaxomicin is also a favorable treatment because it reduces the risk of recurrent C. difficile. And, the researchers stressed, in high-risk populations like the elderly, the cost of fidaxomicin should not be a deterrent. Unlike the other 3 drugs, bezlotoxumab does not disrupt the activity of gastrointestinal microbiota, the study authors added. It was approved for C. difficile treatment by the FDA in October 2016 and is on the verge of becoming an essential therapy for the management of C. difficile.
Fecal microbiota transplant is considered “an effective therapy for recurrent C. difficile infection,” according to the material reviewed by the investigators. FMT appeared to be effective between 80—90% of the time in recurrent C. difficile cases, however, 1 study noted that it should still be considered a risk for elderly patients to undergo FMT. The elderly population may eventually benefit from the developing variety of delivery modalities for FMT, such as oral capsules.
Study authors discussed a variety of other treatment methods as well. For example, they looked at probiotics, but concluded that studies and systematic reviews of the use of probiotics are difficult to interpret. When the researchers examined evidence on combination therapy, they learned that there seemed to be no significant difference between monotherapy and combination therapy in elderly patients. They did see, though, that the rate of adverse drug events was lower in monotherapy than in combination therapy. Finally, the researchers said that the evidence for the use of rifaximin, nitazoxanide, and tigecycline largely comes from case studies, making their effect on the elderly population relatively known.
“According to census data, 15% (approximately 50 million) of the total US population are 65 years and older and this number is projected to increase to 100 million by 2060,” Dr. Asempa added. “Combined with the fact that severe and fatal C. difficile infection predominantly affects our elderly and nursing home patients, the implications of C. difficile infections are quite significant. Financial implications include an excess of $4 billion in US total healthcare costs and clinical implications include a toll on patient functional status, hospital readmissions, medication adverse events and transmission of C. difficile. Public health agencies, health care providers, and antimicrobial stewardship teams need to work together to decrease the burden of C. difficile infections in our aging population.”
The paper, titled “Clostridium difficile infection in the elderly: an update on management,” was published in the journal Clinical Interventions in Aging.