There is a nifty little paper that looks at length of stay in Skilled Nursing Facilities (SNF) for Medicare beneficiaries**. It finds that BMI is a predictor of length of stay and readmission.
Residents with mild (adjusted relative risk (aRR)=1.16, 95% CI=1.12–1.19), moderate (aRR=1.27, 95% CI=1.20–1.35), and severe (aRR=1.67, 95% CI=1.54–1.82) obesity were more likely to be readmitted within 30 days than those who were not obese. The average difference in LOS between residents without obesity and those with mild obesity was 2.6 days (95% CI=2.2–2.9 days); moderate obesity, 4.2 days (95% CI=3.7–5.1 days); and severe obesity, 7.0 days (95% CI=5.9–8.2 days). Residents with obesity were less likely to be successfully discharged and more likely to become long‐stay nursing home residents.
Obesity was associated with worse outcomes in postacute SNF residents with hip fracture. Efforts to provide targeted care to residents with obesity may be essential to improve outcomes. Obesity may be an overlooked risk adjuster in quality‐of‐care measures and in payment reforms related to PAC for individuals with hip fracture.
I want to think about two thinks about risk adjustment. The first is the need to risk adjust bundles. Secondly, I am a bit leery of risk adjusting on controllable variables as it is theoretically ripe for manipulation.
Bundled payments are when a coordinating entity receives one lump sum payment for an entire episode of care. From that lump sum of money all care that is related to the triggering event is paid for. If the coordinating entity can provide the relevant care for less than the bundle, then they profit. If the care costs more than the bundle, then they lose money.
Some bundles are elective and some bundles are emergent/acute care. This particular case is for acute care as no doctor-patient dyads decide that Tuesday would be a great day to break a hip. If there is no risk adjustment for BMI, if a primary care physician (PCP) knows that she is responsible for hip fracture bundles, there will be an incentive for that PCP to select a patient panel that will heal quickly from a fracture event with as little time as possible in a SNF. That patient is far more likely to be profitable in a bundle payment scenario than a patient who projects to need a lot of time in the hospital or a SNF to heal.
Here risk adjustment is critical to make sure that people who have characteristics that project to lead to expensive to treat conditions can actually get care. Weight may be an appropriate risk adjuster for acute, unexpected bundles of care.
The other challenge with risk adjusting on a controllable variable with clear thresholds is manipulation. This matters far more for deferrable bundles of care than unexpected bundles of care. Let’s assume that there is a deferrable episode of care for a patient right on a variable threshold.
Weight varies during the course of a day.## I know my personal weight floats with a local maxima about fifteen minutes after I wake up as I will drink two glasses of water and eat a light breakfast to a daily minima around 4:00 in the afternoon and then another maxima right before bedtime as I drink more water.
Let’s assume that the patient, Mr. Dennison, is 6’3″ and has an average daily weight of 239 pounds. If he is measured at his daily minima, he would not qualify for the risk adjustment multiplier. If he is weighed at his daily maximum, he qualifies for the risk adjustment multiplier as he would be just over the threshold.
If there is money attached to a measurement, incentives come into play. The incentive for a provider that is operating under a deferrable bundle payment where categorical patient weight/BMI drives some payment is to find ways to bump people who are just underneath a threshold that triggers a significantly higher payment to appear to be just over the threshold. Assuming most people have similar weight floats as I do, the incentive would be for the index weigh-in for the marginally unqualified individuals to weigh in at systemically different times than folks who are clearly far away from a threshold point. One or two pounds of “float weight” probably has minimal clinical or cost impact but it could trigger significant additional revenue. This would be one of the easiest games to play on the provider side when risk adjustment is based on a controllable variable with step thresholds.
** Kosar, C. M., Thomas, K. S., Gozalo, P. L., Ogarek, J. A., & Mor, V. (2018). Effect of Obesity on Postacute Outcomes of Skilled Nursing Facility Residents with Hip Fracture. Journal of the American Geriatrics Society. doi:10.1111/jgs.15334
## Yes, I was a wrestler and I also officiated wrestling for years so this is where I gained a sensitivity to daily weight patterns.
One day we will finally understand the obesity epidemic. My money’s currently on the corn syrup added to so many foods. It will turn out that our collective ill health is an externality of big agriculture and big food.
You are making it too complicated. You take the BMI at the time of hospital admission immediately post fracture. The time after surgery to the SNF is short, and while you will get fluid shifts and some catabolic wt loss, you will get a satisfactory representation of body habitus and outcome. The measure might get gamed, but no more than any other measure (CMIs in general come to mind).
I’m not sure why this is a problem. It just means the definition of obesity becomes the patient’s weight at the heaviest time of day. You can’t make anybody fatter than that, so it is what it is. The real problem is the cliff. Weighing one pound more or less doesn’t affect the risk. What you need is a sliding scale, not a cut off.
BMI isn’t independent of height.
I was wondering if you could look into two stories:
Des Moines Register: Hundreds of disabled Iowans are being denied the medical devices they need, including wheelchairs, shower stools and even nutritional supplements, by private Medicaid providers that routinely refuse to pay for them. https://t.co/WV1PfG6Ugn
— Jenna Johnson (@wpjenna) April 8, 2018
Broadening Medicaid would give Virginia Governor Ralph Northam, a Democrat who won by a landslide last year, a major policy victory https://t.co/Sr7N7eIkCt
— NYT National News (@NYTNational) April 8, 2018
@Bradley Flansbaum: For hip fractures, I agree, gaming is hard.
For deferrable bundles (joint replacement for instance) using BMI as a risk adjuster invites gaming.
First name ‘David’ by any chance?
Unlikely. If wt taken in ER or first day on wards, EMR entered data wont be manipulated—that’s stamped and can undergo audit. However, if you tell your front lie staff to put a rock on the bed when they take the weight, yeah, then its Monty Hall time.
I think it’s more that we are shoving too much food into our big mouths.
MIL’s nursing home had average cafeteria main course meals. But the cakes, pies, ice cream, and related were awesome. The folks barely ate their main courses, but they ate the heck out of the desert. MIL was not very mobile, gained a ton of weight in the home, and became less mobile prior to passing. Most everyone in there was large. Plan seemed to be keep the inmates happy with sugar and grease. I thought it was screwed up at the time but never said anything; other than my wife and I grumbling about it.
I get the general point of the article, but color me skeptical about the cited study. There has been push back on the studies that show obesity causes worse results with knee replacement surgery. Like here. One review suggested that the previously recorded worse results may have been related to physicians pushing weight loss before the surgery due to those worse results.
Don’t underestimate the additives.
There are certain realities about obesity that is overlooked all the time. An ideal weight is like other attributes of human beings and depends on each person’s genetics. Our bodies are biologically/gentically programmed for an ideal weight; but, the ideal weight cannot be determined by height/weight charts of people used in the control group who may or may not be the same heritage as any particular person. In the 50s, a common chart used by insurance companies was based on a group of white anglo-saxon (probably protestant) men living in New England. Those charts said I should weigh 100 pounds. However, my weight fluctuated between 120 and 135 pounds. The result was that I spent most of my 20s and 30s thinking I was so grossly fat no one should even look at me. Later, when I was in my 40s and looked at pictures of me during that time period, I discovered I looked fine; I was even somewhat attractive. It annoyed me that I had spent most of my life thinking I was so ugly and undesirable and constantly dieting (which was not good for me either). Also, I am a Pacific Northwest American Indian with some English and Scottish blood, which comes from the Hudson’s Bay Company people who married many of the Indians in this area. I think Ohio Mom an rikyrah have nailed the main culprits to many weight problems in the United States.
Additionally, unlike smoking or drinking habits, all of us human beings NEED food to live! You can remove all cigarettes and booze from your home; but, you cannot remove all your food. In the end, I do not believe that the American health professionals take a very common sense attitude towards the obesity problem. I used to be told (when I was “just right”) that I needed to lose weight by doctors who had a pack of cigarettes in their front pockets. Now, I read labels, shop at a local health food store when possible, and do my best to maintain my current weight. And, if Donald Trump weighs 230 pounds, I’ll eat my hat, which does not have high fructose corn syrup, MSG, or any other additives that are not good for human beings.