{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,21]],"date-time":"2026-09-21T23:49:17Z","timestamp":1790034557508,"version":"4.0.1"},"reference-count":46,"publisher":"MDPI AG","issue":"3","license":[{"start":{"date-parts":[[2025,2,28]],"date-time":"2025-02-28T00:00:00Z","timestamp":1740700800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Medicina"],"abstract":"<jats:p>Background and Objectives: We conducted a meta-analysis to assess the impact of nitrogen-free substitutes for essential amino acids on the progression of chronic kidney disease (CKD). Materials and Methods: A comprehensive literature review conducted up to November 2024 identified 15 studies that involved 1596 participants with CKD at baseline; among them, 797 were on very-low-protein diets (LPDs) enriched with nitrogen-free analogs (NFA), while 799 followed a standard LPD. Results: A very-LPD utilizing NFA showed significantly improved estimated glomerular filtration rate (MD, 1.00; 95% CI, 0.35\u20131.64, p = 0.002), reduced serum creatinine (MD, \u22120.44; 95% CI, \u22120.75 to \u22120.13, p = 0.006), decreased blood urea nitrogen (MD, \u221235.34; 95% CI, \u221264.27 to \u22126.42, p = 0.02), and lower parathyroid hormone levels (MD, \u22121.25; 95% CI, \u22122.33 to 0.18, p = 0.02) when compared to a standard LPD in patients with CKD. Nevertheless, the very-LPD with NFA resulted in no significant differences in serum albumin (MD, 0.08; 95% CI, \u22120.03 to 0.19, p = 0.14), serum cholesterol (MD, \u221217.25; 95% CI, \u221242.79 to 8.29, p = 0.19), serum phosphorus (MD, \u22120.41; 95% CI, \u22120.97 to 0.15, p = 0.15), and serum calcium (MD, 0.16; 95% CI, \u22120.06 to 0.39, p = 0.16) compared to a typical LPD in subjects with CKD. Conclusions: A very-LPD supplemented with NFA showed a notably higher estimated glomerular filtration rate, decreased serum creatinine levels, lower blood urea nitrogen, and reduced parathyroid hormone levels; however, there were no significant differences observed in serum albumin, serum cholesterol, serum phosphorous, and serum calcium when compared to a standard LPD in individuals with CKD. Additional research is necessary to confirm these results.<\/jats:p>","DOI":"10.3390\/medicina61030423","type":"journal-article","created":{"date-parts":[[2025,2,28]],"date-time":"2025-02-28T06:45:42Z","timestamp":1740725142000},"page":"423","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":3,"title":["A Meta-Analysis Examining the Impact of Consuming Nitrogen-Free Analogs of Essential Amino Acids on the Progression of Chronic Renal Disease"],"prefix":"10.3390","volume":"61","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-4950-3472","authenticated-orcid":false,"given":"Mohamed S.","family":"Imam","sequence":"first","affiliation":[{"name":"Department of Clinical Pharmacy, National Cancer Institute, Cairo University, Fom El Khalig Square, Kasr Al-Aini Street, Cairo 11796, Egypt"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Lama Saud Turki","family":"Alrasheedi","sequence":"additional","affiliation":[{"name":"College of Pharmacy, Northern Border University, Rafha 91911, Saudi Arabia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Saleh Ali Hassan","family":"Alyami","sequence":"additional","affiliation":[{"name":"College of Clinical Pharmacy, King Faisal University, Al-Ahsa 31982, Saudi Arabia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Mahdi Mohammed Ahmed","family":"Aljamaan","sequence":"additional","affiliation":[{"name":"College of Clinical Pharmacy, King Faisal University, Al-Ahsa 31982, Saudi Arabia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Khaled Sami Khaled","family":"Alnaim","sequence":"additional","affiliation":[{"name":"College of Clinical Pharmacy, King Faisal University, Al-Ahsa 31982, Saudi Arabia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Hussam Mohsen Ayesh","family":"Alenzi","sequence":"additional","affiliation":[{"name":"College of Clinical Pharmacy, King Faisal University, Al-Ahsa 31982, Saudi Arabia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Nouf Nawaf","family":"Alnufeai","sequence":"additional","affiliation":[{"name":"College of Pharmacy, Taif University, Taif 21944, Saudi Arabia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Daad Adnan Saad","family":"Almalki","sequence":"additional","affiliation":[{"name":"College of Pharmacy, Taif University, Taif 21944, Saudi Arabia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Abdullah S.","family":"Alanazi","sequence":"additional","affiliation":[{"name":"Medical College School of Health and Social Care, Swansea University, Swansea SA1 8EN, UK"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Saud Saad Frais","family":"Alotaibi","sequence":"additional","affiliation":[{"name":"College of Pharmacy, Shaqra University, Shaqra 11961, Saudi Arabia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Naif Fahad Mashaan","family":"Alshaibani","sequence":"additional","affiliation":[{"name":"College of Pharmacy, Shaqra University, Shaqra 11961, Saudi Arabia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0227-8404","authenticated-orcid":false,"given":"Mohamed E. A.","family":"Abdelrahim","sequence":"additional","affiliation":[{"name":"Clinical Pharmacy Department, Faculty of Pharmacy, Beni-Suef University, Beni-Suef 62574, Egypt"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Basma M. E.","family":"Mohamed","sequence":"additional","affiliation":[{"name":"Clinical Pharmacy Department, Faculty of Pharmacy, Beni-Suef University, Beni-Suef 62574, Egypt"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2025,2,28]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"823","DOI":"10.1681\/ASN.V24823","article-title":"Dietary protein restriction in chronic renal failure: Nutritional efficacy, compliance, and progression of renal insufficiency","volume":"2","author":"Mitch","year":"1991","journal-title":"J. Am. Soc. 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