Blog entry by Meguid El Nahas
Nephrology practice, research and publications seem to have been highjacked by spreadhseet nephrologists and biostatisticians who are changing the face of Nephrology and its practice.
They have created a bubble with CKD…; global epidemic of CKD....that never was...Global healthcare threat....that is misunderstood and misrepresented...not to mention the medicalization of the normality of millions of asymptomatic mostly older individuals who suddenly find themselves labelled as suffering from a disease, CKD, they never had…
The Spreadsheet nephrologists and their Biostatistician colleagues went to action some 10-12 years ago, armed with a new CKD classification (KDOQI 2002) based on estimated GFR (eGFR), the new holy grail of Nephrology….
The KDOQI and more recently the KDIGO CKD classifications are based on eGFR and false assumptions emanating from spreadsheet nephrologists and biostatisticians misinterpretation of insufficient and seriously flawed and invalid data.
Most of the KDIGO CKD Cohorts, upon which the new 2012 proposed classification is based, are seriously flawed:
Individuals all over the world, in excess of a million... tested only once, inaccurately with non validated or standardised biochemistry, with wrong assumptions of chronicity who have their data put on spreadsheets and given to biostatisticians sitting in front of their computers crunching these inaccurate data...to come up with all sorts of prediction models and false assumptions....
“Epidemic of CKD”....Wrong!....just an epidemic of misleading biostatistics in an ageing population....
eGFR/Albuminuria powerful and independent predictors of death...Wrong!....just a misinterpretation of the data....data that even those who have put it forward have argued plausibly that it was weak, flawed and not validated to predict mortality or cardiovascular disease....
But this doesnt deter the spreadsheet nephrologists and the Biostatisticians who carry on regardless...and claim in one paper that mortality increases with CKD regardless of individuals' age....
Only to contradict themselves, using the same biostatistics and spreadsheets...., to say that life expectancy is not different between individuals with normal renal function and those with reduced GFR (down to 45ml/min):
Clearly, premature conclusions regarding the incidence, prevalence and prognosis of CKD based on false and invalid assumptions made by spreadsheet nephrologists and biostatisticians who probably never saw a CKD patient beyond their computer spreadsheet and databases…
Same with eGFR, an approximate calculation of true GFR, that is at best confusing and at worst misleading:
eGFR is at the basis of the false assumptions made about CKD prevalence and prognosis.
Based on eGFR <60, millions have CKD; when in reality the measure is at best imprecise and at worst inaccurate...
Mostly, labelling seemingly healthy older individuals as suffering from a disease, CKD, they never had...they just have a slow and expected decline in their organ function including age-related decline in kidney function…a dangerous and misleading medicalization of an growing ageing population…with unwarranted consequences!?
Then, the spreadsheet nephrologists and their biostatisticians tells us that eGFR, with its endless variety of formulas, predicts all sorts of ills...cardiovascular disease (CVD), mortality etc...when in reality all it does...badly...is reflect the prognostic value of its components:
Mostly, Age and Gender, those two integral part of the eGFR formulas and the strongest predictors of CVD and death....
And serum creatinine, which along with Cystatin C, are better predictors of outcomes than their unnecessary formulation into an eGFR:
In fact, eGFR adds little if nothing to standard CVD and mortality prediction models such as the old fashion Framingham Risk Score (FRS):
Beyond the spreadsheet nephrologists, eGFR offers little to jobbing clinical nephrologists:
1. It underestimates true GFR in early CKD
2. It overestimates GFR in late CKD
3. It is useless at reflecting CKD progression
4. Inaccurate in timing RRT as serum creatinine can decrease by up to 20% in CKD5 due to ESRD and its metabolic consequences.
5. Unhelpful in AKI; as useless and not applicable in absence of a steady state
6. Unhelpful in renal transplantation, confounded by medication
So who is eGFR for, other than spreadsheet nephrologists and biostatisticians…???
Perhaps, non nephrologists who don't know the normal range of serum creatinine and make the wrong assumptions based of normal renal function faced with serum creatinine levels that are raised for a given age…mostly older individuals…better knowledge of serum creatinine norms, their population based percentiles and distribution would suffice;
if not just dividing 1 by the serum creatinine level (mg/dl) would give the non-nephrologists a useful enough approximation of GFR to adjust drug dosage and avoid unnecessary nephrotoxicity, without the false pretense of accurate GFR estimation by eGFR...
But perhaps, and after all….eGFR may also be helpful to clinical nephrologists..., as by playing around with formulas they can cure people from CKD…if you have CKD with the MDRD formula, then apply CKD EPI and you are cured…if not try the Virga equation...; after all the prevalence of CKD in the community varies from 5.8% (MDRD), to 3.6% (CKD EPI) to even 1.8% (Virga)…in one stroke the prevalence of CKD can be reduced to a quarter of its original value with the help of...eGFR formulas…and... biostatisticians!!!! ;)