Please see first part of over long post!
This is the second half of my post which broke the word/character count limit.
Rapidly losing the will to live here, but noting:
"Differences in the period covered by the baseline and the follow-up earwax sample may explain why the correlation between the baseline EGC and FSG (R = 0.71, p < 0.001) was much smaller than the association found between the follow-up EGC and PSG (R = 0.90, p < 0.001). This might be explained by the fact that only the amount of secreted earwax at the time of follow-up was standardized. Hence, the baseline period covered by the baseline EGC varied among participants and might have been affected by a range of factors. Aside from biological differences in fasting and postprandial glycemic levels, peaks of hyperglycemia, due to episodes of physical activity or stress before their inclusion in the study, might have affected baseline earwax measurements"
Which I read as saying that the baseline measurement of Earwax Glucose Concentration is not that good because of the indeterminate history of the original syringed sample. Only the sample taken one month later is known to cover a 4 week period.
All in all, as a one time scientist I am not impressed with this study.
It seems to be awash with axes to grind.
Not so much with test results.
It is interesting in showing that earwax includes glucose, and the concentration may well reflect the BG level when the wax was secreted.
However the study was so minor that it seems very wrong to draw any major conclusions.
Significant weaknesses:
- Only 37 participants, all non-diabetic and generally healthy
- Only one true test 4 weeks after ear syringed.
- Lack of further testing to confirm the single result this is all based on (why not 3 * 4 week periods?) to confirm the singleton test result is accurate
- Heavy reliance on a single FBG and a single PBG test to asses the accuracy of EGC and HbA1c testing. Again why no further testing?
- Acknowledges that the accuracy of HbA1c tests is higher for diabetics than non diabetics (who were the test subjects)
- Indirectly recognises the strength of CGM to overcome the original shortcomings of BG testing, but tried to bad mouth the technology
- Acknowledges that cofounders (other influences) can affect the accuracy of HbA1c but does not make any effort to demonstrate that these do not affect EGM - just avoids them in the tests.
Anyway, the paper's summary:
"EGC using the novel device may be a harmless, economic, and suitable test for measuring long-term glucose concentrations."
I have highlighted the word "may" because it is doing a lot of heavy lifting here.
Summary (in my view):
- To be accurate, the subject required the ear to be syringed clean 4 weeks before the first test, and immediately after each test.
- The sample collected (either by syringing or the "novel device") has to go to a laboratory for analysis.
- This obviously requires a clinical visit, as is required now for blood samples for HbA1c.
- This study appears to ignore the fact that routine blood tests often also cover several other measurements such as kidney function and cholesterol, so will still be required.
- The cost of the analysis may be similar to that of HbA1c, or may be more expensive.
- The study is trivial on data and long on speculation. At best it is the foundation of a request for further study. No strong conclusions should be drawn on the basis of this paper.
- Conclusion: not impressed