Neurological dysfunction tied to ischemic injury to kidneys in type 1 diabetes patients

The study was conducted by Yuliya Lytvyn, University of Toronto, Toronto, Ontario, Canada, and colleagues to determine the relationship between renal hemodynamic function and neuropathy in type 1 diabetes (T1D) adults with ≥ 50 years compared to nondiabetic controls.

For this purpose, the researchers measured effective renal plasma flow (ERPF,p-aminohippurate), glomerular filtration rate (GFR, inulin), corneal confocal microscopy, modified Toronto Clinical Neuropathy Score (mTCNS), heart rate variability (autonomic function), and nerve conduction; estimation of (RA) and efferent (RE) arteriolar resistances were done in 74 patients with T1D and 75 controls.

eGFRMDRD < 60 ml/min/1.73 m2 or 24-h urine albumin excretion >30 mg/day defined diabetic kidney disease (DKD) non-resistors. The relationships between renal function and neuropathy measures were examined after adjusting for sex, age, systolic blood pressure, HbA1c, 24-h urine albumin to creatinine ratio, and low-density lipoprotein cholesterol.

The study demonstrated the following findings:

• Higher mTCNS was associated with lower renal blood flow (β ± SE:−9.29 ± 4.20) and greater RE (β ± SE:32.97 ± 15.43) in participants with T1D but not in controls.
• DKD non-resistors had higher mTCNS and worse corneal nerve morphology measures than those without DKD.
• Renal hemodynamic parameters did not associate with autonomic nerve function.

"The findings suggest that neurological dysfunction in diabetes presence may be associated with impaired renal blood flow leading to ischemic injury in type 1 diabetes patients," the researchers wrote in their conclusion. "Early autonomic dysfunction does not seem to contribute to the neurologic dysfunction observed in this cohort of patients."

Reference:

Lytvyn Y, Albakr R, Bjornstad P, Lovblom LE, Liu H, Lovshin JA, Boulet G, Farooqi MA, Weisman A, Keenan HA, Brent MH, Paul N, Bril V, Perkins BA, Cherney DZI. Renal hemodynamic dysfunction and neuropathy in longstanding type 1 diabetes: Results from the Canadian study of longevity in type 1 diabetes. J Diabetes Complications. 2022 Sep 28;36(11):108320. doi: 10.1016/j.jdiacomp.2022.108320. Epub ahead of print. PMID: 36201892.