Thursday August 11 2011
It's best for patients to stay mobile if possible
“Hospital patients who get out of bed to walk around can cut their stay by three days,” reported the Daily Mirror. Those who start strolling on their first day in hospital shorten their visits more than others, it added.
The story is based on a brief article discussing recent studies on how mobility during hospital stays relates to the patient’s length of stay and ability to function. The authors of the article focus on a recent study they conducted in nearly 500 older adults in hospital for acute illness, which found that those who were more mobile had a shorter hospital stay. Specifically, people who were able to walk around at least once a day outside their room left hospital, on average, 1.5 days earlier than those who stayed inside their room.
The report is in line with current thinking that among people recovering from illness, being “up and about” seems to contribute to a faster recovery. However, in this instance the brief report and the study it refers to have some limitations that make it difficult to draw conclusions. For example, the patients estimated their own level of walking, and these estimates could be inaccurate. Furthermore, although the researchers made adjustments to account for the severity of patients’ illness, it is difficult to assess the extent to which being more seriously ill caused people to be bed-bound and hospitalised for longer.
However, while it is not possible to conclude from this research that walking daily shortens a patient’s hospital stay, the current NHS advice states the importance of keeping hospital patients mobile as much as possible, as this can prevent problems such as blood clots and bed sores.
Where did the story come from?
The study was carried out by researchers from Haifa University, Israel. It was partly funded by the Israeli Science Foundation. The study was published in the peer-reviewed medical journal Archives of Internal Medicine.
The Daily Mirror claimed that patients can cut their hospital stay by three days, but this is incorrect. The average difference between the more-mobile and less-mobile patients was 1.5 days. Several papers report that this study found that “walking around on the first day in hospital can shorten the visit”. In fact, this result comes from a previously conducted study commented on by the authors of this new paper.
What kind of research was this?
This is a brief narrative report discussing how mobility during hospitalisation affects patient outcomes. The authors (Shadmi and Zisberg), have written in response to a study recently conducted by another team of researchers (Fisher and co.).The earlier study by Fisher and co., which was recently featured in the same journal, examined how patient mobility related to length of hospital stay. Fisher and co. reportedly found that hospital patients who increased their walking by at least 600 steps within 24 hours were discharged 1.7 days earlier than those who did not. In this new article, Shadmi and Zisberg briefly describe a similar study they have conducted, which looked at how in-patient mobility related to everyday functioning at, and after, the time of discharge. In the article Fisher and co. also provide a response to Shadmi and Zisberg’s commentary and study of functioning, as well a discussion of the wider issue of patient mobility.
Shadmi and Zisberg’s study, published in 2011, looked at the relationship between older people’s mobility when hospitalised for acute medical illness and their ability to function as normal, both at discharge and one month later. In response to the findings by Fisher and co., they appear to have re-analysed their results to see whether there was also an association between mobility and length of stay in hospital in their sample. From the brief report it is not possible to critique the methodology of this analysis or tell whether their study of everyday functioning had been appropriately designed to examine the issue of time in hospital.
From the information available, it appears that the published study was a prospective cohort on patients aged 70 or over which had aimed to examine the in-hospital mobility of a sample of patients and followed their functional outcomes at discharge. The current analysis seems to be retrospective, looking back through data to see if patients’ mobility was also linked to their hospital stay. Prospective analyses are often preferable to retrospective ones because they set a premise and then design a study to examine that specific premise, rather than looking for associations in pre-existing data gathered for other purposes.
What did the research involve?
The researchers looked at 485 adults aged 70 or over who had been admitted to hospital with acute, non-disabling conditions for two days or more. They excluded patients who were transferred to intensive care or other in-patient units.
To assess in-hospital mobility, the researchers used a scale developed by previous researchers to measure frequency of mobility, but modified this scale to include a measure of distance. Their measure relied on patients self-reporting their mobility during their hospital stay, looking at how often patients walked and how far (classified as inside or outside the patient’s hospital room). Their scale had mobility scores ranging from 1 to 14, with higher scores indicating higher mobility. The researchers adjusted their results to take into account the patients’ mobility levels prior to admission and other possible confounders such as:
- functional and cognitive status
- severity of illness
Other than this, little detail is given in this article on how patients were recruited, and other methodological aspects of the study.
What were the basic results?
The authors reported an average hospital stay of 6.2 days. They said they found that a higher score on the mobility scale was associated with a significantly shorter stay in hospital. The hospital length of stay of patients who were mobile at least once a day outside the room was on average 1.5 days shorter (95% confidence interval for the difference between the two groups, 0.53-2.57 days). The results remained significant after adjusting for the above confounders, although they give no details of their adjusted findings, according to the researchers.
How did the researchers interpret the results?
These results, together with those of previous research, emphasise the importance of in-hospital mobility, said the researchers. They recommended that walking guidelines be drawn up for older adults in hospital with acute illness.
This study highlights current thinking that mobility is a factor that can contribute to faster recovery after some illnesses, but it cannot show that keeping mobile while in hospital leads to a shorter hospital stay, for several reasons.
As discussed, this recent article covered by newspapers is a comment piece rather than an in-depth analysis. The brief analysis that it does feature is an examination of earlier study data not originally intended for studying how mobility related to time in hospital. Furthermore, there were some methodological limitations in the earlier study that they discuss, such as relying on patients to estimate their level of walking rather than measuring this independently.
Although the results are said to have been adjusted for the severity of the patient’s illness, adjustments of this type can be difficult to perform accurately and it is still difficult to know for certain that the patient’s illness itself is not confounding the relationship between early mobility and shorter hospital stay. In other words, it is difficult to assess the extent to which being more seriously ill caused patients to be bed-bound and hospitalised for longer.
Overall, it is not possible to conclude from this research whether walking daily while in hospital will directly shorten your hospital stay. However, where possible it is important that hospital patients stay mobile to prevent problems such as blood clots, which are currently a major problem during hospitalisation.