title: Multimorbidity and Patient Safety Incidents in Primary Care: A Systematic Review and Meta-Analysis.
abstract: BACKGROUND
  Multimorbidity is increasingly prevalent and represents a major challenge in primary care. Patients with multimorbidity are potentially more likely to experience safety incidents due to the complexity of their needs and frequency of their interactions with health services. However, rigorous syntheses of the link between patient safety incidents and multimorbidity are not available. This review examined the relationship between multimorbidity and patient safety incidents in primary care.
  
  
  METHODS
  We followed our published protocol (PROSPERO registration number: CRD42014007434). Medline, Embase and CINAHL were searched up to May 2015. Study design and quality were assessed. Odds ratios (OR) and 95% confidence intervals (95% CIs) were calculated for the associations between multimorbidity and two categories of patient safety outcomes: 'active patient safety incidents' (such as adverse drug events and medical complications) and 'precursors of safety incidents' (such as prescription errors, medication non-adherence, poor quality of care and diagnostic errors). Meta-analyses using random effects models were undertaken.
  
  
  RESULTS
  Eighty six relevant comparisons from 75 studies were included in the analysis. Meta-analysis demonstrated that physical-mental multimorbidity was associated with an increased risk for 'active patient safety incidents' (OR = 2.39, 95% CI = 1.40 to 3.38) and 'precursors of safety incidents' (OR = 1.69, 95% CI = 1.36 to 2.03). Physical multimorbidity was associated with an increased risk for active safety incidents (OR = 1.63, 95% CI = 1.45 to 1.80) but was not associated with precursors of safety incidents (OR = 1.02, 95% CI = 0.90 to 1.13). Statistical heterogeneity was high and the methodological quality of the studies was generally low.
  
  
  CONCLUSIONS
  The association between multimorbidity and patient safety is complex, and varies by type of multimorbidity and type of safety incident. Our analyses suggest that multimorbidity involving mental health may be a key driver of safety incidents, which has important implication for the design and targeting of interventions to improve safety. High quality studies examining the mechanisms of patient safety incidents in patients with multimorbidity are needed, with the goal of promoting effective service delivery and ameliorating threats to safety in this group of patients.
authors: NIHR School for Primary Care Research, Centre for Primary Care, Manchester Academic Health Science Centre, University of Manchester, Manchester, United Kingdom.
authors: Maria
authors: M
authors: Panagioti
authors: NIHR Greater Manchester Primary Care Patient Safety Translational Research Centre (Greater Manchester PSTRC), Manchester Academic Health Science Centre University of Manchester, Manchester, United Kingdom.
authors: Jonathan
authors: J
authors: Stokes
authors: NIHR Greater Manchester Primary Care Patient Safety Translational Research Centre (Greater Manchester PSTRC), Manchester Academic Health Science Centre University of Manchester, Manchester, United Kingdom.
authors: Aneez
authors: A
authors: Esmail
authors: NIHR Collaboration for Leadership in Applied Health Research and Care-Greater Manchester and Manchester Academic Health Science Centre, University of Manchester, Manchester, United Kingdom.
authors: Peter
authors: P
authors: Coventry
authors: NIHR Greater Manchester Primary Care Patient Safety Translational Research Centre (Greater Manchester PSTRC), Manchester Academic Health Science Centre University of Manchester, Manchester, United Kingdom.
authors: Sudeh
authors: S
authors: Cheraghi-Sohi
authors: NIHR Greater Manchester Primary Care Patient Safety Translational Research Centre (Greater Manchester PSTRC), Manchester Academic Health Science Centre University of Manchester, Manchester, United Kingdom.
authors: Rahul
authors: R
authors: Alam
authors: NIHR Greater Manchester Primary Care Patient Safety Translational Research Centre (Greater Manchester PSTRC), Manchester Academic Health Science Centre University of Manchester, Manchester, United Kingdom.
authors: Peter
authors: P
authors: Bower
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D015897:Comorbidity; D005260:Female; D006801:Humans; D008297:Male; D019300:Medical Errors / Q000401:mortality / Q000706:statistics & numerical data*; D008875:Middle Aged; D061214:Patient Safety / Q000706:statistics & numerical data*; D011320:Primary Health Care / Q000706:statistics & numerical data*