title: The Effectiveness of Pharmacological and Non-Pharmacological Interventions for Improving Glycaemic Control in Adults with Severe Mental Illness: A Systematic Review and Meta-Analysis.
abstract: People with severe mental illness (SMI) have reduced life expectancy compared with the general population, which can be explained partly by their increased risk of diabetes. We conducted a meta-analysis to determine the clinical effectiveness of pharmacological and non-pharmacological interventions for improving glycaemic control in people with SMI (PROSPERO registration: CRD42015015558). A systematic literature search was performed on 30/10/2015 to identify randomised controlled trials (RCTs) in adults with SMI, with or without a diagnosis of diabetes that measured fasting blood glucose or glycated haemoglobin (HbA1c). Screening and data extraction were carried out independently by two reviewers. We used random effects meta-analysis to estimate effectiveness, and subgroup analysis and univariate meta-regression to explore heterogeneity. The Cochrane Collaboration's tool was used to assess risk of bias. We found 54 eligible RCTs in 4,392 adults (40 pharmacological, 13 behavioural, one mixed intervention). Data for meta-analysis were available from 48 RCTs (n = 4052). Both pharmacological (mean difference (MD), -0.11mmol/L; 95% confidence interval (CI), [-0.19, -0.02], p = 0.02, n = 2536) and behavioural interventions (MD, -0.28mmol//L; 95% CI, [-0.43, -0.12], p<0.001, n = 956) were effective in lowering fasting glucose, but not HbA1c (pharmacological MD, -0.03%; 95% CI, [-0.12, 0.06], p = 0.52, n = 1515; behavioural MD, 0.18%; 95% CI, [-0.07, 0.42], p = 0.16, n = 140) compared with usual care or placebo. In subgroup analysis of pharmacological interventions, metformin and antipsychotic switching strategies improved HbA1c. Behavioural interventions of longer duration and those including repeated physical activity had greater effects on fasting glucose than those without these characteristics. Baseline levels of fasting glucose explained some of the heterogeneity in behavioural interventions but not in pharmacological interventions. Although the strength of the evidence is limited by inadequate trial design and reporting and significant heterogeneity, there is some evidence that behavioural interventions, antipsychotic switching, and metformin can lead to clinically important improvements in glycaemic measurements in adults with SMI.
authors.affiliation: Department of Health Sciences, University of York, York, United Kingdom.
authors.forename: Johanna
authors.initials: J
authors.lastname: Taylor
authors.affiliation: Health Service and Population Research Department, Institute of Psychiatry, Psychology and Neuroscience, King's College London, London, United Kingdom.|Physiotherapy Department, South London and Maudsley NHS Foundation Trust, London, United Kingdom.
authors.forename: Brendon
authors.initials: B
authors.lastname: Stubbs
authors.affiliation: Department of Health Sciences, University of York, York, United Kingdom.
authors.forename: Catherine
authors.initials: C
authors.lastname: Hewitt
authors.affiliation: Leeds Institute of Cardiovascular and Metabolic Medicine, University of Leeds, Leeds, United Kingdom.
authors.forename: Ramzi A
authors.initials: RA
authors.lastname: Ajjan
authors.affiliation: Leeds Institute of Health Sciences, University of Leeds, Leeds, United Kingdom.
authors.forename: Sarah L
authors.identifier: http://orcid.org/0000-0002-5418-0495
authors.initials: SL
authors.lastname: Alderson
authors.affiliation: Department of Health Sciences, University of York, York, United Kingdom.
authors.forename: Simon
authors.initials: S
authors.lastname: Gilbody
authors.affiliation: Human Development and Health Academic Unit, Faculty of Medicine, University of Southampton, Southampton, United Kingdom.
authors.forename: Richard I G
authors.initials: RI
authors.lastname: Holt
authors.affiliation: Leeds and York Partnership NHS Foundation Trust, Leeds, United Kingdom.
authors.forename: Prakash
authors.identifier: http://orcid.org/0000-0002-8692-126X
authors.initials: P
authors.lastname: Hosali
authors.affiliation: Leeds and York Partnership NHS Foundation Trust, Leeds, United Kingdom.
authors.forename: Tom
authors.initials: T
authors.lastname: Hughes
authors.affiliation: Department of Health Sciences, University of York, York, United Kingdom.
authors.forename: Tarron
authors.identifier: http://orcid.org/0000-0002-4062-2539
authors.initials: T
authors.lastname: Kayalackakom
authors.affiliation: School of Psychology, University of Leeds, Leeds, United Kingdom.
authors.forename: Ian
authors.initials: I
authors.lastname: Kellar
authors.affiliation: Department of Health Sciences, University of York, York, United Kingdom.
authors.forename: Helen
authors.identifier: http://orcid.org/0000-0002-2237-1369
authors.initials: H
authors.lastname: Lewis
authors.affiliation: Faculty of Health and Social Sciences, Leeds Beckett University, Leeds, United Kingdom.
authors.forename: Neda
authors.initials: N
authors.lastname: Mahmoodi
authors.affiliation: University of Leeds Library, Leeds, United Kingdom.
authors.forename: Kirstine
authors.identifier: http://orcid.org/0000-0002-7165-5878
authors.initials: K
authors.lastname: McDermid
authors.affiliation: Department of Health Sciences, University of York, York, United Kingdom.
authors.forename: Robert D
authors.initials: RD
authors.lastname: Smith
authors.affiliation: Leeds Institute of Health Sciences, University of Leeds, Leeds, United Kingdom.
authors.forename: Judy M
authors.initials: JM
authors.lastname: Wright
authors.affiliation: Department of Health Sciences, University of York, York, United Kingdom.|Bradford District Care NHS Foundation Trust, Bradford, United Kingdom.
authors.forename: Najma
authors.initials: N
authors.lastname: Siddiqi
mesh_terms: D000328:Adult; D001786:Blood Glucose / Q000187:drug effects; D003920:Diabetes Mellitus / Q000097:blood / Q000188:drug therapy; D005215:Fasting / Q000097:blood; D006442:Glycated Hemoglobin / Q000378:metabolism; D006801:Humans; D001523:Mental Disorders / Q000097:blood / Q000188:drug therapy*; D008687:Metformin / Q000627:therapeutic use
chemical_list: D001786:Blood Glucose; D006442:Glycated Hemoglobin; D008687:Metformin