In a recent study published in BMC Medicine, a group of researchers assessed the safety, feasibility, and impact of kefir administration on the gut microbiome of critically ill adults in an intensive care unit (ICU) setting.
Study: Safety, feasibility, and impact on the gut microbiome of kefir administration in critically ill adults. Image Credit: Fascinadora/Shutterstock.com
Background
Critically ill patients often face gut dysbiosis upon ICU admission, characterized by reduced beneficial microbiome diversity and increased pathogenic bacteria. This imbalance is linked to higher risks of hospital-acquired infections, organ failure, septic shock, and mortality.
The degradation of gut health in the ICU is aggravated by common treatments like antibiotics and steroids, which harm the commensal gut flora. Despite attempts, interventions like probiotics have not significantly improved outcomes.
Fermented foods, particularly kefir, offer a promising alternative due to their health benefits, including enhancing gut microbiome diversity.
Further research is needed to comprehensively understand kefir's effects on gut microbiome diversity and its potential clinical benefits in critically ill patients.
About the study
In the present study, an open-label phase I trial was initiated to explore the safety and feasibility of kefir administration in critically ill adults within an ICU setting, gaining approval from the Mayo Clinic Institutional Review Board (IRB) and deemed an investigational new drug by the Food and Drug Administration (FDA).
Lifeway Foods® provided the kefir, aiming to investigate shifts in gut microbiome composition among ICU patients.
Aiming for at least 50 participants, adults with a functioning gastrointestinal (GI) tract expected to stay in the ICU for over 48 hours were eligible, excluding those with significant immunosuppression, compromised gut integrity, dairy intolerance, or a dire prognosis.
Participants or their proxies consented to the study, which aligned with ethical standards and the Helsinki declaration. Lifeway Foods® Kefir, rich in beneficial bacteria and yeast, was chosen for its potential health benefits.
Administered in increasing doses, the kefir was given either orally or via a nasogastric tube, closely monitoring patient tolerance and adverse reactions.
The primary goals were to evaluate kefir's safety and the ability to deliver prescribed doses effectively. Stool samples were collected for gut microbiome analysis before and after kefir administration processed for deoxyribonucleic acid (DNA) extraction and sequencing to assess microbial diversity and changes.
The study also measured the Gut Microbiome Wellness Index (GMWI) to gauge health improvements, applying rigorous statistical analyses to evaluate the impact of kefir on the gut microbiome.
Study results
Between July 2022 and February 2023, the health records of 722 ICU patients were reviewed for the study on kefir administration, resulting in 54 patients being enrolled based on specific inclusion criteria.
These patients had an average age of 64.6 years and a mean body mass index (BMI) of 34.9, with a predominance of white ethnicity (98%) and a high percentage receiving antibiotic treatments during their ICU stay.
Kefir was administered to patients either orally or via a nasogastric tube, with a high adherence rate to the prescribed doses.
Despite challenges such as taste preferences leading to the introduction of flavored kefir, the study found kefir administration to be feasible and safe, with no severe adverse effects linked to its consumption.
The primary safety concern was diarrhea in two patients, which could not be conclusively attributed to kefir due to concurrent laxative use and the commonality of diarrhea in the ICU setting.
Stool samples collected before and after kefir administration showed significant changes in the gut microbiome of critically ill patients. Despite administering antibiotics, which likely influenced these changes, analysis revealed a decrease in microbial diversity.
However, specific microbial species associated with kefir showed varying presence in the patients' guts, indicating potential engraftment.
The study also explored the impact of kefir on the GMWI, finding a significant improvement in gut health among the ICU patients who received kefir.
This improvement, assessed through changes in the relative abundance of specific microbial species, suggests a positive shift in the gut microbiome composition towards a healthier state following kefir supplementation.
Conclusions
The study demonstrated that kefir administration is safe and feasible for critically ill ICU patients with functional gastrointestinal systems despite not significantly increasing gut microbial diversity.
An observed improvement in the GMWI suggests potential health benefits. Future work would refine kefir dosing, enhance sample collection, and incorporate control groups to more effectively evaluate kefir's benefits on gut health and patient outcomes in the ICU.
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