Studies variously published in medical literature as diverse as the New England Journal of Medicine, the American Journal of Emergency Medicine, Stroke, the Medical Journal of Malaysia, JAMA Surgery, the Health Statistics Centre, Queensland Health, Australia, and BMJ, to name a random few, have identified the ‘weekend effect’ — all finding that patients admitted to the hospital during the weekend have an increased risk of dying.
However, according to research conducted at the Lady Davis Institute at the Jewish General Hospital in Montreal, Quebec, Canada, and published online on May 15 in the European Respiratory Journal, people hospitalized with COPD or pneumonia are more likely to die during a weekend hospital stay. While weekend hospital admissions have been associated with higher mortality rates, this is the first study to assess death rates among patients staying in hospital over the weekend, irrespective of the day of admission.
The researchers, led by Dr. Samy Suissa, Director of the Centre for Clinical Epidemiology, analyzed the ‘weekend effect’ in a different way, investigating whether patients hospitalized for chronic obstructive pulmonary disease (COPD) or pneumonia have higher mortality during weekend and Friday stays. They used medical records to examine death rates in 323,895 people over the age of 50 who were admitted to hospital with either COPD or pneumonia between 1990 and 2007, and assessing whether patients who stayed in hospital over weekends, even if they were admitted earlier in the week, were also experiencing an increased risk of death. The hazard ratio (HR) of in-patient death associated with Friday and weekend stay was estimated by the Cox model with time-dependent covariates, adjusted for age, sex and comorbidity.
Entitled “Friday and weekend hospital stays: effects on mortality” (European Respiratory Journal, 2014; DOI: 10.1183/09031936.00007714), is coauthored by Samy Suissa, Sophie Dell’Aniello, Daniel Suissa and Pierre Ernst, of the Center for Clinical Epidemiology, Lady Davis Institute, Jewish General Hospital, the Departments of Epidemiology and Biostatistics and of Medicine, McGill University, Montreal, and the Dept of Plastic Surgery, Université de Montréal.
The study results demonstrated that irrespective of when patients are admitted to hospital, if they stay over the weekend their risk of death is increased. During weekdays, the death rate was 80 per 10,000 per day. On a Friday, the risk of death increased by 5 percent, suggesting an additional 4 deaths per 10,000. On a Saturday and Sunday the risk increased by 7 percent suggesting an additional 5.6 deaths per 10,000 for each weekend day.
The researchers suggest that while this phenomenon could be attributed to relative shortages of staff on weekends, or it could also be due to the fact that more severe patients will admit themselves to hospital during a weekend, while those with milder symptoms would wait to speak to their doctor the following week.
Whichever, the findings suggest that the increase in the risk of death is due to a reduced quality of care, or reduced access to high quality care at the weekend — an effect that appears to begin on Friday.
Study lead author Dr. Sami Suissa says in a release: “Our study is the first to report an increase in mortality for patients staying in hospital over the weekend. The findings of our study have huge implications for the way healthcare is delivered across the globe. It may be time to reconsider the weekend concept in the healthcare calendar to avert a significant number of likely preventable deaths.”
Dr. Suissa is Director of the Centre for Clinical Epidemiology, Lady Davis Institute, and Professor, Departments of Epidemiology and Biostatistics and of Medicine, McGill University. Dr. Suissa heads the Canadian Network for Observational Drug Effect Studies (CNODES) and the McGill Pharmacoepidemiology Research Unit. He was the founding Director of the Quebec Research Network on Medication Use, funded by the FRSQ.
Dr. Suissa’s research is in pharmacoepidemiology which involves studying the risks and benefits of medications at the within the population at large. He specializes in the exploitation of existing computerized health databases to rapidly evaluate these risks. He has developed, and published extensively on, new methods of data analysis and study design that allow more rapid and accurate assessments of drug safety. He has conducted pharmacoepidemiological studies of several medications used for the treatment of chronic diseases, including asthma and COPD, cardiovascular and rheumatic diseases, and women’s health issues. He has lectured extensively throughout the world, and is the author of more than 360 peer-reviewed research papers published in scientific journals.
The Lady Davis Institute (LDI) is the research arm of Montreal’s Jewish General Hospital, a teaching hospital of McGill University. It is among Canada’s leading medical research institutions. Major fields of inquiry include cancer, hemovascular diseases, epidemiology, diseases of aging, HIV/AIDS, and psychosocial science. Important discoveries made at the LDI have contributed to the health and well-being of patients in Quebec, Canada, and around the world since its founding in 1969.
The Lady Davis Institute (LDI) at the Jewish General Hospital
European Respiratory Journal
The Lady Davis Institute