Hospital 'Weekend Effect' Study Settles the Causes—and Solutions

The weekend effect is linked to reduced hospital staff. But there are five fixes, available even to small community hospitals, starting with EMR systems.

After years of research and dozens of studies, most people in healthcare accept that the "weekend effect" is real. What has remained in contention is what causes patients to suffer worse outcomes when they require hospitalization between Friday afternoon and Monday morning. Now a new study nails down why the weekend effect happens, and shows how hospitals—including small community hospitals with limited resources—can overcome it.

The study, by researchers at Loyola University Medical Center in suburban Chicago, provides more evidence that patients who undergo emergency or urgent surgery on the weekends have longer hospital stays. Study co-author Anai Kothari, MD, a general surgery resident at Loyola, says it makes sense "intuitively" that the weekend effect is linked to reduced hospital staff, rather than any characteristics of patients hospitalized on weekends.

"You're working on the weekend with a smaller staff, and the resources aren't as readily available," Kothari says. "So, despite having maybe equal patient characteristics on the weekdays and weekends, the things in the ecosystem surrounding the patients on the weekend are different."

Kothari and his colleagues say that five resources can mitigate the weekend effect. They are increased nurse-to-bed ratio, full adoption of electronic medical records, inpatient physical rehabilitation, a home health program, and a pain management program.

The study, which appeared this month in Annals of Surgery, examined more than 126,000 emergency/urgent surgeries for appendectomies, hernias, and gall bladder removals that were conducted from 2007 to 2011 at 166 Florida hospitals. Using length of stay as the metric over the five-year span, the study found that 41 hospitals experienced a weekend effect for all five years, 87 hospitals wavered between having a weekend effect one year and no weekend effect the next year, 21 hospitals developed weekend effect during the study period, and 17 hospitals overcame the weekend effect using the five resources identified above.

"To us, the most striking thing was that the weekend effect is not inevitable," Kothari says. "A lot of people say the weekend effect exists and permeates throughout everything, but really there are hospitals that have it, there are hospitals that don't, and there are things you can do to avoid it. Understanding that it is a hospital-dependent feature was totally surprising to us."

As expected, the study's finding suggest that nurse-to-bed ratios play a role in the weekend effect; the higher the ratio, the lower the weekend effect. However, the biggest single factor reducing weekend effect was the adoption pf electronic medical records. Hospitals with full EMR systems were 4.7 times more likely to overcome the weekend effect. Only 12.2% of hospitals that had persistent weekend effect had fully adapted EMR, compared with 40% of hospitals that overcame the weekend effect.

Kothari and his co-authors "spent a lot of time talking around the table about why that would be," he says. "Our hypothesis is that a lot of this is influenced by care coordination. It's the same with ancillary or supportive services that have the same ability to look into the EMR and see what's been going on with that patient. So you have continuity of care even if you don't have continuity of personnel. We are trying to study that going forward to see if there are parts of the EMR specifically, whether it's clinical support systems, electronic medical reconciliation, or what pieces of the EMR are influencing the weekend effect."

One reason why the weekend effect has been so difficult to solve is that it is not universal, Kothari notes. "That is both encouraging and concerning in the sense that you first have to evaluate locally do you have the weekend effect or not. Then, once you are able to accept that, it's a prime target for intervention because it can make a difference without, hopefully, major changes."

If you want to measure the weekend effect at your hospital, Kothari says the answer might already reside in your EMR. "To us it seems like a ripe place to start," he says. "There are a lot of people who study the weekend effect in different ways. Some people ask, is our mortality higher on the weekend versus the weekday? But oftentimes if you don't have enough patients, it's hard to see the difference, or if there is high-risk surgery being done in both settings, it is hard to see a difference. We focused on length of stay for that reason, because it's easy to see differences in length of stay. The things that you can potentially influence can impact length of stay. That is a straightforward way for a smaller community hospital."

The healthcare industry shifts toward population health management and value-based care will likely create more incentives to identify and reduce the weekend effect.

Kothari says these efforts are overdue—and that the problem goes beyond weekend variability.

"It's not just the weekend effect; it falls under this larger umbrella of temporal patterns of care, where some people talk about the July effect, or the seasonality of care," he says. "It's all these things when you are talking about population health and value-based care that have to be considered, especially when you are structuring policy."