Shrunken Pore Syndrome Is Associated With Increased Levels of Atherosclerosis-Promoting Proteins

Shrunken Pore Syndrome (SPS), originally defined by eGFRcystatin C being less than 60% of eGFRcreatinine in the absence of extrarenal influences on the plasma levels of cystatin C or creatinine (Grubb A, Lindström V, Jonsson M, et al. 2015), is associated with a high increase in mortality, even in the absence of reduced GFR (Dardashti A, Nozohoor S, Grubb A et al. 2016).

The objective of the present study was to determine if the proteome of patients with SPS shows differences from that of patients with normal or reduced measured GFR (mGFR) without SPS. Four patient cohorts were included: one with normal mGFR without SPS; one with normal mGFR with SPS; one with reduced mGFR without SPS; and one with reduced mGFR with SPS.

The plasma levels of 177 selected proteins were analysed. Differences in the levels of 30 proteins were specific for SPS, 31 differences were specific for patients with both SPS and reduced mGFR, and 27 were specific for reduced mGFR. Eighteen of the differences specific for SPS concerned proteins described as promoting, or being associated with, atherosclerosis. Twelve of the differences specific for patients with both SPS and reduced mGFR and 10 of the differences specific for reduced mGFR also concerned proteins described as promoting, or being associated with, atherosclerosis. Almost all (82 of 88) of the concentration differences represented increased levels. For SPS, but not for reduced mGFR, a correlation between protein size and increase in level was observed, with smaller proteins being associated with higher levels.