Hospitals are places where we go to find comfort and relief from whatever ails us, but now it seems that when hospitals are full or near capacity, that may not always the case. In fact, according to a new study published in the journal Medical Care, in certain cases, patients admitted to crowded hospitals stand a 5.6% higher risk of dying. The findings are applicable to hospitals nationwide due to the large size of the study, which encompassed over 166,000 patients who were admitted to 29 hospitals.

Researchers arrived at their conclusions by evaluating a number of important factors that influence hospital mortality, including occupancy, staffing levels of nurses, admission times, and seasonal flu. While these issues have been examined in the past, this study was the first to look at the impact of all four simultaneously.

Hospital occupancy was studied every day over the course of three years. Patients first entered via the emergency room (ER) for one of several conditions which included a heart attack, heart failure, stroke, pneumonia, hip fracture, or intestinal bleeding. They were then admitted, on average, when the hospital was operating at 73% capacity. One third of the patients were admitted during more crowded periods, where occupancy was at 80% or more.

The findings indicate that some of the issues increased the likelihood of survival (more nurses), while others raised the risk of death. Included in the latter group were the wide distribution of seasonal flu, which had the greatest effect at 11.7%, as well as hospitals operating at or near capacity.

The authors note that they have not identified an occupancy threshold over which patient suffering and hospital mortality rates suddenly increase. This point can be influenced by a number of factors, and will most likely differ from hospital to hospital. More importantly, the researchers believe that they have identified a potential relationship between a circumstance that may be controllable and an adverse outcome. With this mind, it would hopefully lead to measures to help reduce the risk of death.

This includes better preparation for those situations that have some level of predictability. For instance, peak flu seasons occurs generally around the same time, and vaccinations among health care workers as well as increased diligence about proper hygiene might help to reduce the burden.

And while it may be impossible to predict the number of patients who will enter the ER, hospitals can moderate, to some degree, the overwhelming impact of peak admissions through the scheduling of elective surgery. However, these procedures are big money makers for hospitals, possibly discouraging them to scale back on them.

This post was included in the latest Health Wonk Review blog carnival.