Proneurotensin/Neuromedin N and Risk of Incident CKD and Other Kidney Outcomes in Community-Living Individuals: The REGARDS Study.

ABSTRACT

Rationale & Objective: Plasma proneurotensin/neuromedin N (pro-NT/NMN) is a precursor of neurotensin, a tridecapeptide linked with type 2 diabetes mellitus and other comorbid conditions associated with kidney disease. Whether pro-NT/NMN is directly associated with incident chronic kidney disease (CKD), and whether that association differs by race, is uncertain. We evaluated whether pro-NT/NMN levels were associated with increased risk of kidney outcomes. Study Design: Prospective cohort. Setting & Participants: Participants in Biomarker Mediators of Racial Disparities in Risk Factors, a nested cohort from the REasons for Geographic And Racial Differences in Stroke study, with available stored serum and urine samples from baseline and second visits for biomarker measurement. Exposure Baseline log-transformed pro-NT/NMN. Outcomes: Incident CKD, progressive estimated glomerular filtration rate (eGFR) decline, incident albuminuria, and incident kidney failure within median follow-up time of 9.4 years. Analytical Approach: Logistic regression. Results: Among 3,914 participants, the mean ± SD age was 64 ± 8 (SD) years, 48% were women, and 51% were Black. Median baseline eGFR was 90 (IQR, 77-102) mL/min/1.73 m2. Each SD higher of pro-NT/NMN was associated with 9% higher odds of progressive eGFR decline (OR, 1.09; 95% CI, 1.00-1.20). There was no association observed with incident CKD (OR, 1.10; 95% CI, 0.96-1.27), incident albuminuria (OR, 1.08; 95% CI, 0.96-1.22), or incident kidney failure (OR, 1.10; 95% CI, 0.83-1.46). There were no differences in results by race or sex. Limitations: Single measurement of pro-NT/NMN and limited generalizability. Conclusions: Higher pro-NT/NMN was associated with progressive eGFR decline but no other manifestations of kidney disease incidence.

Neurotensin is a peptide secreted by the small intestine in response to a meal. Higher levels of neurotensin and its stable precursor, proneurotensin/neuromedin N (pro-NT/NMN), have been associated with cardiovascular disease and type 2 diabetes mellitus, important risk factors for the development of kidney disease. Whether pro-NT/NMN is directly associated with kidney outcomes has been less studied and has been done so in largely homogenous cohorts of White participants. Using the REasons for Geographic And Racial Differences in Stroke study, we followed Black and White participants and evaluated the risk of developing kidney outcomes. We found that elevated levels of pro-NT/NMN were associated with kidney function decline. Pro-NT/NMN may help individuals who may benefit from closer monitoring of kidney function.