Background Overweight and obesity are highly prevalent in people with severe mental illness (SMI). Antipsychotic-induced weight gain (AIWG) is one of the most commonly reported and distressing side effects of treatment and people living with SMI place a high value on the avoidance of this side effect. Metformin is the most effective pharmacological intervention studied for the prevention of AIWG yet clear guidelines are lacking and evidence has not translated into practice. The aim of this research was to develop a guideline for the use of metformin for the prevention of AIWG. Study Design The appraisal of guidelines for research and evaluation II instrument (AGREE II) was followed for guideline development. Literature was reviewed to address key health questions. The certainty of evidence was evaluated using GRADE methodology and an evidence-to-decision framework informed the strength of the recommendations. A consensus meeting was held where the algorithm and strength of recommendations were agreed. An independent external review was conducted involving experts in the field, including patient and public partners. Study Results Metformin is the only pharmacological agent that has demonstrated efficacy for preventing AIWG. Co-commencement with antipsychotic medicines can reduce the extent of weight gain by 4.03 kg (95% CI −5.78 kg to −2.28 kg) compared to controls. A guideline for the use of metformin for the prevention of AIWG was developed with specific recommendations for co-commencement of metformin at initiation with an antipsychotic or commencement if certain criteria are present. Core recommendations were graded as strong by consensus agreement. Conclusions This is the first published evidence-based guideline using the AGREE II framework and GRADE methods for the use of metformin to prevent AIWG incorporating recommendations for co-commencement. Implementation and evaluation of the guideline will be supported by a shared decision-making package and assessment of barriers and facilitators to implementation.

中文翻译：

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二甲双胍预防抗精神病药诱导的体重增加：指南制定和共识验证


背景 超重和肥胖在严重精神疾病 （SMI） 患者中非常普遍。抗精神病药诱导的体重增加 （AIWG） 是治疗中最常见和最令人痛苦的副作用之一，SMI 患者非常重视避免这种副作用。二甲双胍是研究用于预防 AIWG 的最有效药物干预，但缺乏明确的指南，证据尚未转化为实践。本研究的目的是制定使用二甲双胍预防 AIWG 的指南。研究设计 遵循研究和评价指南指南评估 II 工具 （AGREE II） 进行指南制定。对文献进行了综述，以解决关键的健康问题。使用 GRADE 方法评估证据质量，证据决策框架为建议的强度提供了信息。举行了一次共识会议，就算法和建议的强度达成了一致。进行了一次独立的外部审查，涉及该领域的专家，包括患者和公共合作伙伴。研究结果二甲双胍是唯一已被证明对预防 AIWG 有效的药物。与对照组相比，与抗精神病药物联合使用可使体重增加的程度减少 4.03 kg（95% CI -5.78 kg 至 -2.28 kg）。制定了使用二甲双胍预防 AIWG 的指南，其中具体建议在开始时使用二甲双胍与抗精神病药同时服用，如果存在某些标准，则开始服用二甲双胍。核心建议经共识一致评为强。 结论 这是第一个发表的使用 AGREE II 框架和 GRADE 方法的循证指南，用于使用二甲双胍来防止 AIWG 纳入共同启动的建议。该指南的实施和评估将得到共享决策包和对实施障碍和促进因素评估的支持。