My doctor was concerned about the high BUN/creatinine ratio
that showed up on my annual blood work. After looking back at a couple of years’
previous blood work results, she concluded that the number was going up. I
looked back eight years in my own records and found that it had actually
bounced around, although it was generally higher starting in 2008, when I amped
up my exercise routines with interval work on the cross trainer. The original reading,
taken on 7/19/13 was 36; a second reading, on 8/21/13 was lower but still high,
32.
After the second high reading, I wanted to know what factors
other than kidney disease could affect the test. My doctor’s office always tells
me to fast before checking my cholesterol or blood glucose but does not give me
any particular instructions relating to the BUN test. Yet it turns out that
both exercise and diet the day before can affect its results. One website
suggests not doing either cardio or weightlifting the day before. WebMD
recommends not eating a lot of protein for 24 hours before the test. The day
before the third test I heeded this advice; I did no exercise and ate virtually
no protein. The third test showed a BUN/creatinine ratio of 19, within the
normal range. Within the space of two weeks the number had dropped by one-third. If the BUN is so sensitive
to extraneous factors, should it really be considered a reliable indicator of
kidney health?
I’ve read that cholesterol tests too can be affected by what
you eat the day before but no doctor’s office has ever cautioned me about this.
Speaking of not following recommended protocols, both WebMD and Medline Plus
say that, before your blood pressure is taken, you should sit quietly for at
least five minutes. The medical staff I have dealt with recently never do this.
Instead they take it while I am in the middle of a conversation with them. Then
they tell me I have high blood pressure, which I know is not true because I
take it myself at home; it’s about 105 over 60. I wonder how many people
receive unnecessary treatment because medical tests are being improperly administered.
