Clinical and prognostic values of urinary alpha1-microglobulin as a tubular marker in acute heart failure. (1st September 2021)

• Record Type: Journal Article
• Authors: Ishiwata, Sayaki; Matsue, Yuya; Nakamura, Yutaka; Dotare, Taishi; Sunayama, Tsutomu; Suda, Shoko; Yatsu, Shoichiro; Kato, Takao; Hiki, Masaru; Kasai, Takatoshi; Minamino, Tohru
• Is Part Of: International journal of cardiology. Volume 338(2021)
• Page Start: 115
• Page End: 120
• Publication Date: 2021-09-01
• Subjects: Acute heart failure -- Alpha-1-microglobrin -- Tubular dysfunction -- Prognosis; Cardiology -- Periodicals; Electronic journals; 616.12
• DOI: 10.1016/j.ijcard.2021.06.041
• Languages: English
• ISSNs: 0167-5273

Abstract

Abstract: Background: Although urinary alpha-1-microglobulin has been used as a marker of tubular dysfunction, its clinical and prognostic values in patients with acute heart failure have not been validated. Methods: We analyzed 623 patients (74 ± 13 years old, 60.0% male) with acute heart failure in whom urinary alpha-1-microglobulin (A1MG) levels were measured as tubular markers at the time of admission. The primary endpoint was all-cause mortality. Results: The median levels of urinary alpha-1-microglobulin with and without correction for urinary creatinine concentration were 8.80 (interquartile range: 4.20–17.7) mg/dL and 12.9 (5.92–30.7) mg/gCr, respectively. Urinary A1MG levels were significantly correlated with all of beta-2-microglobulin ( r = 0.77), N -acetyl-β-D-glucosaminidase ( r = 0.51), and estimated glomerular filtration rate ( r = −0.42); however, alpha-1-microglobulin was most often predicted using beta-2-microglobulin or N -acetyl-β-D-glucosaminidase. During the 488-day (interquartile range: 185–938 days) follow-up, 141 deaths occurred. Higher A1MG levels were associated with higher mortality even after adjustment for other covariates. Only A1MG, but not beta-2-microglobulin or N -acetyl-β-D-glucosaminidase, yielded incremental prognostic information in addition to the preexisting prognostic factors (net-reclassification improvement: 0.254, P = 0.023; integrated discrimination improvement: 0.015, P = 0.028). Conclusions: In patients hospitalized due to acute heart failure, urinary alpha-1-microglobulin was a marker of tubular dysfunction. High alpha-1-microglobulin was associated with all-cause mortality independent of glomerular function and was a better predictor of mortality than urinary beta-2-microglobulin. Highlights: Urinary A1MG corrected for urinary creatinine concentration was strongly associated with tubular dysfunction rather than glomerular dysfunction, which implies increased A1MG levels likely reflect tubular damage in patients with AHF. Increased A1MG was associated with an increased risk of all-cause mortality independently of other prognostic covariates, including glomerular function, and this association was almost linear. A1MG yielded significant incremental prognostic information in addition to known risk factors. This is the first study showing the clinical and prognostic values of urinary A1MG in patients with AHF.