Risk Factors for Retinal Detachment: A Case-Control Study

Objective:The aim of this study was to investigate risk factors for retinal detachment or tear (RD/T), and follow up two studies that found increased risk from work-related heavy lifting.Methods:We conducted a case-control study including 200 cases of RD/T and 415 controls. Participants completed a questionnaire covering general health, vision, and physical exertion. Multiple logistic regression and propensity score matching was used to control confounding and estimate independent effects.Results:RD/T risk was increased by one lifting measure: current regular lifting of more than 30lbs (>13.6kg). In the population aged less than 65 years, the odds ratio comparing those with/without heavy lifting was 1.81, 95% confidence interval=1.08 to 3.04.Conclusion:Occupational heavy lifting may represent a risk factor for RD/T, but further research is needed in populations with frequent heavy physical exertion to more precisely quantify the risk

The ASOS Surgical Risk Calculator: development and validation of a tool for identifying African surgical patients at risk of severe postoperative complications

Background: The African Surgical Outcomes Study (ASOS) showed that surgical patients in Africa have a mortality twice the global average. Existing risk assessment tools are not valid for use in this population because the pattern of risk for poor outcomes differs from high-income countries. The objective of this study was to derive and validate a simple, preoperative risk stratification tool to identify African surgical patients at risk for in-hospital postoperative mortality and severe complications. Methods: ASOS was a 7-day prospective cohort study of adult patients undergoing surgery in Africa. The ASOS Surgical Risk Calculator was constructed with a multivariable logistic regression model for the outcome of in-hospital mortality and severe postoperative complications. The following preoperative risk factors were entered into the model; age, sex, smoking status, ASA physical status, preoperative chronic comorbid conditions, indication for surgery, urgency, severity, and type of surgery. Results: The model was derived from 8799 patients from 168 African hospitals. The composite outcome of severe postoperative complications and death occurred in 423/8799 (4.8%) patients. The ASOS Surgical Risk Calculator includes the following risk factors: age, ASA physical status, indication for surgery, urgency, severity, and type of surgery. The model showed good discrimination with an area under the receiver operating characteristic curve of 0.805 and good calibration with c-statistic corrected for optimism of 0.784. Conclusions: This simple preoperative risk calculator could be used to identify high-risk surgical patients in African hospitals and facilitate increased postoperative surveillance. © 2018 British Journal of Anaesthesia. Published by Elsevier Ltd. All rights reserved.Medical Research Council of South Africa gran