Table 2. Summary of findings for comparison of indicated outcomes between PLA and Abx.
| Outcome | Illustrative comparative risks* (95% CI) | Relative effect (95% CI) | No of participants (studies) | Quality of the evidence (GRADE) | Comments | |
|---|---|---|---|---|---|---|
| Assumed risk-PLA | Corresponding risk-Abx | |||||
| HOMA-IR | Mean HOMA-IR in the PLA group was 3.6 to 8.7 | Mean HOMA-IR in Abx group was 0.09 higher (0.96 lower to 1.13 higher) | – | 58 (2 RCTs) | Very lowa,b | – |
| BW, kg | Mean BW in the PLA group was 122.6 kg | Mean BW in Abx group was 4.1 kg higher (23.77 lower to 31.97 higher) | – | 20 (1 RCT) | Very lowa,b | – |
| Rate of diarrhea | 0% | Not estimate | – | 80 (2 RCTs) | Lowc | – |
| GLP-1, pmol/L | Mean GLP-1 in the PLA group was 9.3 pmol/L | Mean GLP-1 in Abx group was 0.20 pmol/L higher (2.36 lower to 2.76 higher) | – | 38 (1 RCT) | Very lowa,b | – |
| Fecal SCFAs, μmol/g Acetate | Mean acetate in the PLA group was 45.0 ìmol/g | Mean acetate in Abx group was 13.60 ìmol/g lower (22.43 to 4.77 lower) | – | 56 (1 RCT) | Moderateb | – |
| Butyrate | Mean butyrate in the PLA group was 12.6 ìmol/g | Mean butyrate in Abx group was 7.60 ìmol/g lower (10.97 to 4.23 lower) | – | 56 (1 RCT) | Moderateb | – |
| Propionate | Mean propionate in the PLA group was 12.5 ìmol/g | Mean propionate in Abx group was 1.10 ìmol/g lower (4.18 lower to 1.98 higher) | – | 56 (1 RCT) | Moderateb | – |
Overview of study design: patients or study population: adult subjects (age ≥18 years) with obesity (body mass index ≥25 kg/m2). Subjects with active infection, and subjects who took antibiotics for other diseases were excluded. Setting: primary care. Intervention: oral antibiotics treatment. Comparison: placebo, non-intervention, or usual care. *, the risk in the intervention group (and its 95% CI) is based on the assumed risk in the comparison group and the relative effect of the intervention (and its 95% CI). a, downgraded by two levels for limitations of study or studies: high risk of bias associated with deviations from intended interventions and missing outcome data. b, downgraded by one level for imprecision: optimal information size criterion was not met. c, downgraded by two levels for imprecision: optimal information size criterion was not met. Abx, antibiotics; BW, body weight; CI, confidence interval; GLP, glucagon-like peptide; HOMA-IR, homeostasis model assessment of insulin resistance; MD, mean difference; PLA, placebo; RCT, randomized controlled trial; SCFA, short-chain fatty acid. GRADE Working Group grades of evidence: high quality: we are very confident that the true effect lies close to that of the estimate of the effect. Moderate quality: we are moderately confident in the effect estimate: the true effect is likely to be close to the estimate of the effect, but there is a possibility that it is substantially different. Low quality: our confidence in the effect estimate is limited: the true effect may be substantially different from the estimate of the effect. Very low quality: we have very little confidence in the effect estimate: the true effect is likely to be substantially different from the estimate of effect.