Use of a non-invasive biomarker salivary alpha-amylase to assess the role of probiotics in sleep regulation and stress attenuation in surgical patients

Abstract

Background and Aims: The influence of gut microbiota on human behaviour, stress and sleep is currently a novel topic of research. A prospective double-blind randomised trial was planned to find out whether probiotics by alteration of the gut microbiome can allay surgery-related stress and improve sleep. Methods: A total of 160 elective surgical patients were randomised to receive either probiotic or placebo capsule twice daily for four and a half consecutive preoperative days. They were subjected to the Perceived Stress Scale (PSS) questionnaire, a psychomotor vigilance task (PVT) and estimation of salivary alpha-amylase (SAA), a well-known biomarker of stress on the evening of admission and on the evening just before the day of scheduled surgery. Data were analysed using Chi-square test, Student's t-test and Mann–Whitney test. Results: On comparing between the two groups, there was a significant difference in PSS scores, SAA levels and PVT scores after probiotic/placebo therapy. There was a decrease in the PSS scores by 11.38% (P < 0.05) and SAA levels by 11.38% (P < 0.05) and an increase in the PVT scores (12.13%, P < 0.05) following probiotic treatment.There was a mean difference of 52.85 in SAA levels in probiotic group and − 69.32 in placebo group with a definite fall in SAA levels in probiotic group, which showed that these patients had reduced stress levels and improved psychomotor vigilance implying improved sleep. Conclusion: Gut microbiome alteration with probiotics results in lowering of psychological stress and sleep improvement in the preoperative period in surgical patients.

Evaluating the effect of preoperative interventions on sleep health in the perioperative period: a systematic review

“…Trials were further subdivided by delivery timepoint such that trials delivered exclusively in the preoperative period were separated from those delivered both preoperatively and postoperatively (i.e., perioperative interventions). In all, 28 were randomised trials (Babaee et al, 2007; de Moor et al, 2008; Dianatkhah et al, 2015; Erz et al, 2022; Farr et al, 2001; Garssen et al, 2013; Gross et al, 2017; Hansen et al, 2014; Heidarnia et al, 2005; Kekecs et al, 2014; Kilpio et al, 2021; Knoerl et al, 2022;Kurdi et al, 2021; Liu et al, 2020; Madsen et al, 2016; Mousavi Malek et al, 2018; Muneyyirci‐Delale et al, 2007; Myles et al, 2004; Ou et al, 2021; Roehrs & Roth, 2017; Savci et al, 2011; Shakya et al, 2019; Stoerkel et al, 2018; Villacampa et al, 2022; Wong et al, 2012; Yang et al, 2021; Yang et al, 2022; Zhao et al, 2022;) and 19 were non‐randomised trials (Adriaans et al, 2022; Alejo et al, 2019; Bagaphou et al, 2019; Barral et al, 2020; Brunet et al, 2017; Diaz & Larsen, 2005; Febrero et al, 2018; Gong et al, 2018; Hassamal et al, 2016; Li et al, 2022; Loughney et al, 2017; Morielli et al, 2016; Ren et al, 2020; Rouhani et al, 2014; Singh et al, 2017; Singh et al, 2018; Wong et al, 2014; Zheng et al, 2022). Overall, 4937 participants were included in these 47 trials.…”

“…The risk of bias of the RCTs is presented in Figure S2 (Sterne et al, 2019). The risk of bias judgements were as follows: 11 were high risk of bias (Babaee et al, 2007; de Moor et al, 2008; Dianatkhah et al, 2015; Erz et al, 2022; Heidarnia et al, 2005; Madsen et al, 2016; Mousavi Malek et al, 2018; Ou et al, 2021; Roehrs & Roth, 2017; Shakya et al, 2019; Zhao et al, 2022), 13 had some concerns (Farr et al, 2001; Garssen et al, 2013; Gross et al, 2017; Kekecs et al, 2014; Kilpio et al, 2021; Knoerl et al, 2022; Liu et al, 2020; Muneyyirci‐Delale et al, 2007; Myles et al, 2004; Stoerkel et al, 2018; Villacampa et al, 2022; Yang et al, 2021), and four were low risk of bias (Hansen et al, 2014; Kurdi et al, 2021; Wong et al, 2012; Yang et al, 2022). In randomised trials, failure to pre‐register and potential of selective reporting was a common source of bias (i.e., selection of the reported result).…”

“…Sleep was a primary outcome in 16 (34%) trials when considering all trial designs (Brunet et al, 2017; Canfield et al, 2021; de Moor et al, 2008; Dianatkhah et al, 2015; Diaz & Larsen, 2005; Farr et al, 2001; Garssen et al, 2013; Kilpio et al, 2021; Kurdi et al, 2021; Li et al, 2022; Mousavi Malek et al, 2018; Ou et al, 2021; Ren et al, 2020; Shakya et al, 2019; Wong et al, 2014; Yang et al, 2021). In all, 24 (51%) trials were delivered exclusively in the preoperative period, whereas the remaining studies contained both pre‐ and postoperative intervention components (i.e., perioperative interventions).…”

“…There was significant heterogeneity in intervention design across the trials. For example, 29 trials used non‐pharmacological interventions including exercise, nutrition, psychological intervention, sleep, and one intervention that was specific to the surgical procedure (Adriaans et al, 2022; Alejo et al, 2019; Babaee et al, 2007; Barral et al, 2020; Brunet et al, 2017; Canfield et al, 2021; de Moor et al, 2008; Diaz & Larsen, 2005; Farr et al, 2001; Febrero et al, 2018; Garssen et al, 2013; Gong et al, 2018; Gross et al, 2017; Hassamal et al, 2016; Heidarnia et al, 2005; Kekecs et al, 2014; Knoerl et al, 2022; Kurdi et al, 2021; Li et al, 2022; Loughney et al, 2017; Morielli et al, 2016; Mousavi Malek et al, 2018; Roehrs & Roth, 2017; Savci et al, 2011; Singh et al, 2017; Singh et al, 2018; Stoerkel et al, 2018; Wong et al, 2014; Yang et al, 2021; Yang et al, 2022). Enhanced recovery after surgery (ERAS) or enhanced nursing protocols were used in eight trials, characterised by inpatient interventions primarily delivered by nurses (Erz et al, 2022; Gong et al, 2018; Kilpio et al, 2021; Liu et al, 2020; Ou et al, 2021; Ren et al, 2020; Zhao et al, 2022; Zheng et al, 2022).…”

“…In all, 11 trials assessed sleep using outcomes not listed above, including: sleep latency (Li et al, 2022; Madsen et al, 2016; Ou et al, 2021; Roehrs & Roth, 2017; Shakya et al, 2019; Zheng et al, 2022), circadian temperature rhythm (Farr et al, 2001), sleep satisfaction (Wong et al, 2014), psychomotor vigilance (Kurdi et al, 2021), sleep/wake time (Canfield et al, 2021), and consumption of sleeping pills (Barral et al, 2020). In addition, one trial (Zheng et al, 2022) reported the percentage of rapid eye movement (REM) sleep and Arousal Index measured via PSG.…”