Article type
Year
Abstract
Background: Overuse and inappropriate use of antibiotics (AB) have been identified as major contributing factors in the rise of antibiotic resistance. Immunisation has the potential to reduce AB use through reduction of bacterial disease incidence and of symptom-based prescribing for viral or parasitic diseases.
Objectives: This systematic review, commissioned by the Wellcome Trust, aimed to provide a comprehensive and up-to-date assessment of the evidence relating to the effect of vaccines on AB use.
Methods: This systematic review and meta-analysis was conducted in accordance with the Cochrane Handbook and GRADE recommendations. Electronic databases were searched for randomized controlled trials (RCTs) and observational studies (published January 1999 to March 2018) comparing vaccines to placebo, no vaccine or another vaccine. The primary outcome of interest was AB use. Abstracts and full texts were screened, and data was extracted and cross-checked independently by two reviewers. Risk of bias in observational studies was assessed using the Cochrane Risk of Bias in Non-randomized Studies of Interventions tool or the Cochrane Effective Practice and Organisation of Care suggested risk of bias criteria.
Results: We identified 4980 records; assessed 895 full-text reports; and included 96 studies (24 RCTs, 72 observational). Included studies were overwhelmingly from high-income countries. Of 96 included studies, only 6 were from eastern Asia, 2 from South America and 1 from Africa. AB use measurements varied widely, reducing the potential to synthesise results.
From RCTs, there was high certainty evidence that intranasal influenza vaccine reduces days of AB use among healthy adults (1 RCT; n = 4253; rate reduction 28·1% [95% CI 16·0, 38·4]); moderate certainty evidence that influenza vaccines probably reduce AB use in children aged 6 months to 14 years (3 RCTs; n = 610; ratio of means 0·62 [95% CI 0·54, 0·70) and that immunisation of children aged 3-15 years probably reduces community AB use (1 RCT; n = 10,985 person-seasons; risk ratio 0·68 [95% CI 0·58, 0·83]). There was moderate certainty evidence that pneumococcal vaccination probably reduces AB use in children aged six weeks to six years (2 RCTs; n = 47,945; rate ratio 0·93 [95% CI 0·87, 0·99]) and reduces illness episodes requiring ABs in children aged 12-35 months (1 RCT; n = 264; rate ratio 0·85 [95% CI 0·75, 0·97]). Other RCT evidence was of low or very low certainty. The majority of the observational studies did not appropriately adjust estimates of AB use for confounding and were considered to be at critical or high risk of bias.
Conclusions:Although vaccination may reduce AB use, the evidence base is poor, particularly in developing regions. There was a large variety of outcome measures used in the different trials which were considered to report “antibiotic use”. Future randomised trials assessing the effect of vaccinations should collect and report standardised measures of AB use.
Patient or healthcare consumer involvement: None
Objectives: This systematic review, commissioned by the Wellcome Trust, aimed to provide a comprehensive and up-to-date assessment of the evidence relating to the effect of vaccines on AB use.
Methods: This systematic review and meta-analysis was conducted in accordance with the Cochrane Handbook and GRADE recommendations. Electronic databases were searched for randomized controlled trials (RCTs) and observational studies (published January 1999 to March 2018) comparing vaccines to placebo, no vaccine or another vaccine. The primary outcome of interest was AB use. Abstracts and full texts were screened, and data was extracted and cross-checked independently by two reviewers. Risk of bias in observational studies was assessed using the Cochrane Risk of Bias in Non-randomized Studies of Interventions tool or the Cochrane Effective Practice and Organisation of Care suggested risk of bias criteria.
Results: We identified 4980 records; assessed 895 full-text reports; and included 96 studies (24 RCTs, 72 observational). Included studies were overwhelmingly from high-income countries. Of 96 included studies, only 6 were from eastern Asia, 2 from South America and 1 from Africa. AB use measurements varied widely, reducing the potential to synthesise results.
From RCTs, there was high certainty evidence that intranasal influenza vaccine reduces days of AB use among healthy adults (1 RCT; n = 4253; rate reduction 28·1% [95% CI 16·0, 38·4]); moderate certainty evidence that influenza vaccines probably reduce AB use in children aged 6 months to 14 years (3 RCTs; n = 610; ratio of means 0·62 [95% CI 0·54, 0·70) and that immunisation of children aged 3-15 years probably reduces community AB use (1 RCT; n = 10,985 person-seasons; risk ratio 0·68 [95% CI 0·58, 0·83]). There was moderate certainty evidence that pneumococcal vaccination probably reduces AB use in children aged six weeks to six years (2 RCTs; n = 47,945; rate ratio 0·93 [95% CI 0·87, 0·99]) and reduces illness episodes requiring ABs in children aged 12-35 months (1 RCT; n = 264; rate ratio 0·85 [95% CI 0·75, 0·97]). Other RCT evidence was of low or very low certainty. The majority of the observational studies did not appropriately adjust estimates of AB use for confounding and were considered to be at critical or high risk of bias.
Conclusions:Although vaccination may reduce AB use, the evidence base is poor, particularly in developing regions. There was a large variety of outcome measures used in the different trials which were considered to report “antibiotic use”. Future randomised trials assessing the effect of vaccinations should collect and report standardised measures of AB use.
Patient or healthcare consumer involvement: None