Daily Archives: December 23, 2024
Guideline: Metformin to Prevent Antipsychotic-Induced Weight Gain
23 Dec, 2024 | 20:55h | UTCIntroduction:
This guideline was developed to address a pressing need for strategies to prevent antipsychotic-induced weight gain (AIWG), a frequent and troubling adverse effect of treatment in individuals with severe mental illness (SMI). Although metformin has shown consistent benefits in mitigating weight gain when initiated alongside antipsychotics, clinical uptake remains limited. The guideline follows the AGREE II framework and synthesizes both randomized and observational research, including Cochrane and meta-analytic data. The primary objective is to outline explicit indications, dosing approaches, and duration for using metformin to avert AIWG.
Key Recommendations:
- Co-initiation With High-Risk Agents: In patients requiring higher-risk antipsychotics (olanzapine, clozapine), start metformin simultaneously. Evidence suggests that concurrent treatment may lessen weight gain by 3 to 5 kg in the early months, potentially yielding greater benefits over time.
- Co-initiation With Medium-Risk Agents: For individuals prescribed quetiapine, paliperidone, or risperidone who have at least one cardiometabolic risk factor (such as diabetes, prediabetes, hypertension, or BMI above 25) or who are 10 to 25 years old, begin metformin at antipsychotic initiation to curb rapid weight changes.
- Initiation During the First Year: If, at any point in the first year of antipsychotic treatment, weight gain exceeds 3% over baseline, consider adding metformin regardless of the antipsychotic being used.
- Titration Schedule and Safety: The guideline advises starting at 500 mg once daily, then moving to 500 mg twice daily after about two weeks, with subsequent increases every two weeks up to 1 g twice daily (2 g/day) as tolerated. Metformin must be discontinued if lactic acidosis is suspected, if BMI falls below 20, or if the antipsychotic is stopped. Avoid its use in harmful alcohol consumption.
- Additional Treatment Options: In cases of obesity (BMI ≥30) or comorbid metabolic disorders, clinicians should consider adding glucagon-like peptide-1 receptor agonists (GLP-1) where available. If cost, supply, or access is limited, metformin remains a practical alternative.
Conclusion:
This is the first evidence-based guideline focused on preventing AIWG by starting metformin at the time of antipsychotic initiation or upon early weight gain signs. By reducing the magnitude of weight increase, metformin may alleviate health risks tied to obesity, as well as psychological distress and nonadherence to treatment. Implementing the guideline involves continuous weight monitoring, structured dose adjustments, and shared decision-making. Ensuring clear communication about benefits and potential side effects will be crucial for sustaining adherence and improving patient outcomes.
Reference:
Carolan A, Hynes-Ryan C, Agarwal SM, Bourke R, Cullen W, Gaughran F, Hahn MK, Krivoy A, Lally J, Leucht S, et al. Metformin for the Prevention of Antipsychotic-Induced Weight Gain: Guideline Development and Consensus Validation. Schizophrenia Bulletin. 2024; sbae205.
DOI: https://doi.org/10.1093/schbul/sbae205
Additional Commentaries:
- Psychiatric News Alert: https://alert.psychnews.org/2024/12/new-guideline-advises-metformin-to.html
- Zagorski N. Metformin May Reduce Weight Gain in Youth Taking Antipsychotics. Psychiatric News. 2024; 59(01). https://psychiatryonline.org/doi/full/10.1176/appi.pn.2024.01.1.22
2025 ASA Practice Advisory for the Perioperative Care of Older Adults Undergoing Inpatient Surgery
23 Dec, 2024 | 20:27h | UTCIntroduction: This summary outlines the American Society of Anesthesiologists (ASA) 2025 advisory on optimizing perioperative care for older adults (age 65 years or older) undergoing inpatient surgery. It focuses on preoperative, intraoperative, and postoperative measures to mitigate cognitive complications, especially delirium and longer-term cognitive decline, in a population that is highly vulnerable to functional deterioration and loss of independence. The recommendations are based on systematic reviews and meta-analyses, supplemented by expert consensus where evidence is limited. Although not intended as strict standards of care, these advisory statements provide practical guidance that can be adapted to local contexts and patient-specific needs.
Key Recommendations:
- Expanded Preoperative Evaluation:
- Incorporate frailty assessment, cognitive screening, and psychosocial or nutritional evaluations into routine preoperative workups for older patients.
- Patients identified with frailty or cognitive deficits should receive targeted interventions, such as geriatric co-management, deprescribing when indicated, and early family education about delirium risks.
- Evidence suggests a modest decrease in postoperative delirium when such evaluations are included.
- Choice of Primary Anesthetic (Neuraxial vs. General):
- Current studies do not demonstrate a clear advantage of neuraxial over general anesthesia in reducing postoperative delirium risk.
- Both approaches are acceptable; individualize decisions based on patient factors, surgical requirements, and preference-sensitive discussions.
- Maintenance of General Anesthesia (Total Intravenous vs. Inhaled Agents):
- Data are inconclusive regarding delirium prevention, with no significant difference between total intravenous anesthesia (TIVA) and inhaled volatile agents.
- Some low-level evidence indicates TIVA might reduce short-term cognitive decline, but this effect is inconsistent over longer follow-up.
- Dexmedetomidine for Delirium Prophylaxis:
- Moderate-level evidence supports dexmedetomidine for reducing delirium incidence in older patients, yet its use may increase bradycardia and hypotension.
- Optimal dosing and timing remain uncertain, and baseline patient vulnerability should inform decisions.
- Medications with Potential Central Nervous System Effects:
- Drugs such as benzodiazepines, antipsychotics, anticholinergics, ketamine, and gabapentinoids warrant careful risk-benefit analysis.
- Current findings are inconclusive, suggesting neither a firm endorsement nor outright disapproval; preexisting conditions and polypharmacy should guide individualized treatment plans.
Conclusion: Preserving cognitive function and independence in older adults undergoing inpatient surgery is a growing priority. These recommendations highlight the importance of comprehensive preoperative screenings (frailty, cognition, and psychosocial domains), shared decision-making when choosing anesthetic techniques, and thoughtful use of pharmacologic agents. While dexmedetomidine shows promise in mitigating delirium, vigilance regarding hypotension and bradycardia is essential. Ultimately, these strategies aim to reduce anesthesia-related complications in older patients by addressing the multifaceted determinants of postoperative cognitive outcomes.