Body Mass Index (BMI)

From the CDC:

Body Mass Index (BMI) is a person’s weight in kilograms divided by the square of height in meters. A high BMI can be an indicator of high body fatness. BMI can be used to screen for weight categories that may lead to health problems but it is not diagnostic of the body fatness or health of an individual.

I’ve read before that BMI is not really useful as an indicator of overall health since it only takes weight and height into consideration. However, I think a lot of transplant centers use BMI as a criteria for transplant acceptance, both for live donors and recipients. I don’t know UCLA’s cutoff but the last time I was there in October, I weighted 221 lbs and they calculated a BMI of 30.8. In the After Visit Summary document, they have a chart titled Commonly accepted BMI ranges:

30.0 to 34.9	Class 1 (low-risk) obesity
35.0 to 39.9	Class 2 (moderate-risk) obesity
> 40.0	Class 3 (high-risk) obesity

There were no instructions regarding the BMI reading of 30.8 so I assume Class 1 obesity was acceptable for transplant. Since heart surgery, I’ve dropped some weight. My last weigh in at home 15 minutes ago was 200.4 lbs. That calculates out to a BMI of 27.9. Still “overweight” but out of the “obese” category. Again per the CDC, for my height, normal weight range would be from 133 to 179 lbs. So if I drop another ~20 lbs, I will be in the “normal” range for the first time in probably 30+ years. My weight has stabilized after surgery at ~200 lbs however. I feel the fluctuations now are just due to fluid removal during dialysis.

BMI history from Fitbit. Since I was weighing myself on the wireless scale daily while on peritoneal dialysis, there is a lot of data. The big drop was actually in December when they got rid of excess fluid from the surgery by taking out a lot of fluid during dialysis each day. On November 10th, I was still ~230 lbs and even after surgery, on November 24th, I was still around the same weight. By December 3rd I was down to ~220 lbs and then ~210 lbs by December 6th. I think there was an extra dialysis day during that time, and I was pulling out extra fluid with the remaining PD solution. A week later, I was around ~205 lbs and it has remained between 201 to 206 lbs on the scale, depending on the dialysis cycle and what I’m wearing at weigh-in.

I think dropping another 20 lbs will be difficult since I’m not eating full meals at the moment. My nephrologist expects me to gain weight when I start eating “normal” again. I’ll need to bring up the 179 lbs goal to the dietitians and exercise specialists at cardiac rehab to see what they can recommend.