Factors Associated With Perioperative Outcomes in Non-emergency Surgery

Study Overview
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Brief Summary
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This epidemiological study investigates the association of recent stroke, acute coronary syndrome or pneumonia and adverse perioperative outcomes following elective non-cardiac and cardiac surgery using routinely collected UK primary and secondary care patient data.

Detailed Description
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Previous studies have identified prior stroke, heart attack or current diabetes mellitus and anaemia as important risk factors for adverse outcomes following surgery. Recent heart attacks are associated with greater risks than older ones. While recent data suggests that newer strokes impart significantly greater risk than older strokes, there is a lack of concordance on the literature on this, despite the plausibility of the finding. Despite knowledge that prior pneumonia has long-term health risks, there is a lack of data on whether prior pneumonia influences perioperative risk or whether the time interval from pneumonia to surgery affects this relationship. Furthermore while diabetes mellitus and anaemia are known to be important perioperative risk factors, the relationship between haemoglobin concentration or HbA1c levels and perioperative outcomes is unclear. The aim of this epidemiological study is to explore these associations with perioperative risk in the United Kingdom Clinical Practice Research Datalink (with linkage to Hospital Episode Statistics data and Office of National Statistics mortality data). The research aims are: To investigate the association between three recent acute medical events (stroke, pneumonia and MI) and adverse perioperative outcomes following non-cardiac and cardiac surgery. To investigate the association between time-elapsed between acute medical events (stroke, pneumonia and MI) and adverse perioperative outcomes following non-cardiac and cardiac surgery. To investigate numerical risk thresholds for haemoglobin and HbA1c that could predict adverse perioperative outcomes following non-cardiac and cardiac surgery.

Official Title
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An Epidemiological Investigation Into the Association Between Recent Stroke, Acute Coronary Syndrome or Pneumonia and Adverse Perioperative Outcomes Following Elective Non-cardiac and Cardiac Surgery

Conditions
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Stroke, Acute Coronary Syndrome, Pneumonia

Intervention / Treatment
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* Other: stroke or myocardial infarction or pneumonia


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Undergone a non-cardiac or cardiac elective procedure between 1/01/2004 and 31/12/2013 Exclusion Criteria: None
Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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Accepts Healthy Volunteers

Study Plan
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How is the study designed?
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Arms and Interventions

| Intervention/Treatment |
| --- |
|Other: stroke or myocardial infarction or pneumonia|There are three main exposure groups with exposure defined as a binary variable (yes/no): Stroke in the six months prior to surgery; Myocardial infarction in the six months prior to surgery; Pneumonia in the six months prior to surgery|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Perioperative mortality (yes/no) | all-cause mortality within the specified time frame; both in and out of hospital; as recorded in primary care patient record and validated using Office of National Statistics death certification records; unadjusted and adjusted relative risks will be calculated (odds ratios and hazard ratios) | up to 60 days of surgery | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Acute coronary syndrome (yes/no) | physician diagnosed and occurring within the specified time frame; as recorded in patient care record; unadjusted and adjusted relative risks will be calculated (odds ratios and hazard ratios) | within 30 days of surgery | 
| Pneumonia (yes/no) | physician diagnosed and occurring within the specified time frame; as recorded in patient care records; unadjusted and adjusted relative risks will be calculated (odds ratios and hazard ratios) | within 30 days of surgery | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Mortality, Perioperative period, Elective surgical procedures