Health for life

If youre having difficulty keeping your resolution to exercise 30 minutes a day, 5-days-a-week, then youre going to like this study.

Researches put young men through some very brief, but strenuous, workouts and found their sensitivity to insulin (and so their blood sugar levels) improved:

Extremely Short Duration High Intensity Interval Training Substantially Improves Insulin Action In Young Healthy Males, BMC Endocrine Disorders, January 2009

A total of 16 men, average age 21, underwent 6 sessions of exercise over 14 days.

A session of exercise consisted of:

• 30 seconds of cycling as fast as possible
  
• 4 minutes of rest
  
• The above repeated 4 to 6 times

An exercise session lasted 17 to 26 minutes, but only 2 to 3 minutes of that was actual exercise.

Compared to before training (baseline):

• Postprandial glucose levels declined 12% (measured by AUC: Area Under the Curve)
  
• Postprandial insulin levels declined 37% (AUC)
  
• Postprandial free fatty acid levels declined 26% (AUC)
  
• Insulin sensitivity improved 23% (measured by Cederholm index)
  
• Aerobic cycling performance improved 6%

The authors concluded:

"The efficacy of a high intensity exercise protocol, involving only ~250 kcal of work each week, to substantially improve insulin action in young sedentary subjects is remarkable. This novel time-efficient training paradigm can be used as a strategy to reduce metabolic risk factors in young and middle aged sedentary populations who otherwise would not adhere to time consuming traditional aerobic exercise regimes."

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Im baaaaack!

When persons are admitted to a hospital, insurers payment rates are based on the diagnosis, not the number of days in the hospital (known as a "length of stay").  As a result, once the admission is triggered, the hospital has important economic incentive to discharge the patient as quickly as possible.  The Disease Management Care Blogs physician colleagues used to refer to this as "treat, then street."

Unfortunately, discharging patients too soon can result in readmissions.  Thats why the DMCB has agreed with others that diagnosis-based payment systems and a policy of "no pay" for readmissions were working at cross purposes.  Unified bundled payment approaches like this seem to be a good start.

But thats all theoretical.  Whats the science have to say?

Peter Kaboli and colleagues looked at the push-pull relationship between diagnosis-based payment incentives  and the likelihood of readmissions in a scientific paper just published in the Annals of Internal Medicine. 

The authors used the U.S. Veterans Administration (VA) Hospitals "Patient Treatment Files" to examine length of stay versus readmissions in 129 VA hospitals.  The sample consisted of over 4 million admissions and readmissions (defined as within 30 days and not involving another institution) from 1997 to 2010. The mean age started out at 63.8 years and increased to 65.5 years, while the proportion of persons aged 85 years or older increased from 2.5% to 8.8%. Over the years, admissions also grew more complicated with a higher rate of co-morbid conditions, such as diseases of the kidney (from 5% to 16%).

As length of stay went down, readmissions should have gone up, right?

The answer was yes and no.

Yes, if the data were trended over time: Over the 14 year period of observation, the number of days in the hospital (length of stay or LOS) decreased from 6.0 days to 4.3 days.  Yet, as LOS decreased, readmissions also decreased from 16.6% to 15.2%. 

The decreases held up when the LOS was risk-adjusted for hospital and patient characteristics.  There was also no increase in mortality rates

No, if hospitals were compared to each other:  Hospitals with risk-adjusted low lengths of stay had higher readmission rates compared to their average peers.  In that group, each day of saved LOS was associated with a 6% increased rate of 30-day readmissions.

It gets even more complicated.  As the LOS increased beyond the average, each additional day in the hospital was associated with a 3% increased rate of 30-day readmissions.

What should the DMCB learn from these data?  Keeping in mind that the VA is not necessarily generalizable to the typical community medical center,

1. Over 14 years of worth of VA data for 129 hospitals suggest it is possible to have your cake (a lower LOS) and eat it too (lower readmissions).  Thats the good news.

2. While overall performance improved over the years, between hospital comparisons showed there is a "U" shaped relationship between days in the hospital and the likelihood of readmission.  The DMCB agrees with the authors: premature discharge before the patient is ready is associated with an 6% per day readmission rate, while patients who are very sick and have to stay a few extra days in the hospital are also at risk to the tune of 3% per day.  Thats the sobering news.

What are the implications?

Overzealous efforts to discharge patients can backfire with readmissions.  It appears theres an optimum length of stay that minimizes, but will never eliminate, readmissions.

Patients who do go home "too soon" or need extra days in the hospital appear to be at special risk.  Accountable care organizations and population health management service providers should use this information to target patients at special risk of "treat, street and... repeat."