Abstract
Metabolic syndromes are considered a significant risk factor for renal impairment in renal transplant patients. However, the impact of metabolic syndrome on long-term kidney function is still unclear. This study aims to review the medical literature to investigate the long-term impact of metabolic syndrome on renal impairment in kidney donors. The literature was evaluated through PubMed, Embase, Cochrane, and CINAHL databases in the duration between 1990 and May 2019. Searching terms included synonyms and components for "metabolic syndrome," "renal impairment," "kidney donors," combined with the operators "OR" and "AND." Following this, results were refined to include only original research articles evaluating the long-term effects of kidney donation on kidney function in donors with metabolic syndrome. Eligible trials mentioned the exact duration of follow-up. A total of 820 articles were recovered. After the exclusion of articles on animals and including only analyses on humans, 38 studies appeared. A total of eight studies were considered eligible, covering a total of 1574 living donors with metabolic syndrome. Two studies were observational cohort, while three studies were retrospective and three randomized controlled studies. Living donors with metabolic syndrome are at risk of reduced renal functions of the remaining kidney after donation, with obesity appearing to be the significant contributor. Further randomized controlled studies with a longer follow-up duration are required.