Relationship Between Leptin Level, Inflammation, and Volume Status in Maintenance Hemodialysis Patients

Abstract

Maintenance hemodialysis (HD) patients often experience fluctuations of volume status. Although hypervolemia possibly induces systemic inflammation, the relationship between volume status and leptin has not yet been well defined. The aims of this study were to determine the levels of leptin, C-reactive protein (CRP), and ferritin in relation to volume status and to assess the relationship between leptin and volume and inflammatory status in chronic HD patients. This prospective study included 93 HD patients divided, based on evaluation using the body composition monitor, into normovolemic and hypervolemic groups (overhydration/extracellular water [OH/ECW] ≤ 15% and OH/ECW > 15%, respectively). The levels of leptin and inflammatory markers (CRP, ferritin) were determined during a mid-week dialysis session in all patients. There were more hypervolemic patients after 12 months of follow up than at baseline (41% vs. 38%). Hypervolemic patients had significantly lower leptin levels (11.42 ± 19.24 ng/mL vs. 34.53 ± 40.32 ng/mL at baseline and 13.41 ± 22.04 ng/mL vs. 41.54 ± 21.78 ng/mL at 12 months), longer time on dialysis, and poorer nutritional status than normovolemic patients. Inflammation was present regardless of the volume status, but hypervolemic patients had significantly higher CRP and ferritin than normovolemic patients. A statistically significant reverse correlation was found between leptin level, hyperhydration index, and OH/ECW. No significant correlation was found between leptin and inflammatory markers CRP and ferritin.

Relationship between serum leptin levels, non-cardiovascular risk factors and mortality in hemodialysis patients

“…Our results showed that nutritional, volume and inflammation status change with leptin level. We found similar results with other authors [5,15,16,21]. Several studies have shown decreased leptin levels in severely malnourished dialysis patients [5,13,21].…”

“…In our study, the deceased patients were older than the living patients, , they had a lower nutritional status and decreased leptin levels, they had an increased inflammation parameter and were hypervolemic. In hemodialysis patients, overhydration is associated with malnutrition and inflammation, representing a strong predictor of all-cause mortality in this population [3,5,[14][15][16]. Malnutrition and inflammation often occur together and overlap, and these two entities in HD patients are viewed together as a malnutrition and inflammation complex syndrome [17 ].…”

“…Hemodialysis patients have constant variations in volemic status, with frequent weight gain between hemodialysis. These results results in constant volume loading, problems in determining and achieving dry weight, changes in body composition, numerous complications lead to poor outcome in hemodialysis patients [5]. In the late 1990s, inflammation was recognized as an essential part of chronic kidney disease, and important risk factor for HD morbidity and mortality [6].…”

“…In HD patients , leptin levels are elevated due to decreased renal excretion [11,12]. Leptin is involved in the regulation of appetite and might have a role in the development of anorexia in uremia [5,13]. Studies in HD patients have shown that leptin values correlate with nutritional status, and that leptin may indicate malnutrition in these patients [13].…”

Hypothalamic Energy Regulatory Peptides in Chronic Kidney Disease

“…Indeed, leptin seems to be the main hormone substantially affected by ESA therapy but it was not measured in our study. Leptin is a very well‐known hormone involved in the regulation of appetite and shown to be involved in the development of anorexia in CKD . Also, it is closely related to the hormones measured in this study.…”