Glomerular filtration rate and the risk of strokeBMJ 2010; 341 doi: https://doi.org/10.1136/bmj.c4390 (Published 30 September 2010) Cite this as: BMJ 2010;341:c4390
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Kidney function and cardiovascular risk; an index for the daily
As Perkovic and Cass explain (BMJ 9 Oct. 2010), measuring kidney
function may improve stratification of cardiovascular risk and targeting
of preventive treatments. For the clinical practice it means that the
presence of chronic kidney disease (either reduced eGFR or albuminuria,
but especially both) should act as a "red flag" that triggers
cardiovascular risk assessment and implementation of appropriate
The reciprocal of serum creatinine (1/SCr) is frequently used as a
simple but inaccurate estimated glomerular filtration rate (eGFR)
I proposed years ago to investigate the possible usefulness and
accuracy of 1/SCr divided by the
PULSE MASS INDEX or PMI (see details bellow).
For example, for a normal SCr of 1.1 mg/dl and a normal PMI of 1.0,
the eGFR would be 0.9 or 90% of normal. For a SCr of 1.5, it would be
0.66. If the PMI was 1.3, which is common in patients with a high global
cardiovascular risk according to the Framingham Risk Equation, the eGFR
would be 0.7 (70 % of normal) in the case of 1.1 mg SCr or 0.51 (less than
60 % of normal) for a SCr of 1.5 mg.
The higher the PULSE MASS INDEX, the lower the expected eGFR for a
given value of SCr.
Using one of the original examples from Rule, if a 50-year-old woman
presented to donate a kidney and had a Mayo Clinic serum creatinine of 1.1
mg/dL , she would have an eGFR of 90 mL/min per 1.73 m2 (equation 3). If
this woman had a BMI of 27 (69 kg, 1.6m), and a RHR (resting heart rate)
of 80, her PULSE MASS INDEX would be 1.25, her global cardiovascular risk
over 20%, and her eGFR 0.73 (73% of normal). This eGFR is normal, but less
than ideal, reflecting her higher cardiovascular risk.
The PULSExMASS INDEX (PMI) is calculated as follows: Body Mass Index
(BMI) multiplied by Resting Heart Rate (RHR) and divided by 1730 (24x72).
The normal values of BMI (average 24) are similar in males and females.
The RHR (average 72) reflects the basal metabolic rate and related
factors, both in healthy, fit, potential donors, and in sick people.
The PULSE MASS INDEX reflects all these elements and correlates
highly with the body surface area, the metabolic rate, and the global
cardiovascular risk, with a high correlation with the Framingham risk
score (known to be elevated in renal patients), being the PULSE MASS INDEX
much easier to calculate.
If 1/SCr/PMI resulted acceptably accurate to estimate the GFR, it
would facilitate the daily work with renal patients, the estimation of
their cardiovascular risk and the therapeutic decisions.
Prof. Enrique Sanchez-Delgado
Hospital Metropolitano Vivian Pellas
Reference 1.Gilbert Ross, Jeff Stier, Donald M Lloyd-Jones, Daniel
Levy, Enrique S?nchez-Delgado, et al. Lifetime risk of developing coronary
heart disease. Lancet 1999 (13 March); 353:924-925
Competing interests: No competing interests