Serum leptin, resistin, and lipid levels in patients with end stage renal failure with regard to dialysis modality

Sterile inflammation of peritoneal membrane caused by peritoneal dialysis: focus on the communication between immune cells and peritoneal stroma

Peritoneal dialysis is a widely used method for treating kidney failure. However, over time, the peritoneal structure and function can deteriorate, leading to the failure of this therapy. This deterioration is primarily caused by infectious and sterile inflammation. Sterile inflammation, which is inflammation without infection, is particularly concerning as it can be subtle and often goes unnoticed. The onset of sterile inflammation involves various pathological processes. Peritoneal cells detect signals that promote inflammation and release substances that attract immune cells from the bloodstream. These immune cells contribute to the initiation and escalation of the inflammatory response. The existing literature extensively covers the involvement of different cell types in the sterile inflammation, including mesothelial cells, fibroblasts, endothelial cells, and adipocytes, as well as immune cells such as macrophages, lymphocytes, and mast cells. These cells work together to promote the occurrence and progression of sterile inflammation, although the exact mechanisms are not fully understood. This review aims to provide a comprehensive overview of the signals from both stromal cells and components of immune system, as well as the reciprocal interactions between cellular components, during the initiation of sterile inflammation. By understanding the cellular and molecular mechanisms underlying sterile inflammation, we may potentially develop therapeutic interventions to counteract peritoneal membrane damage and restore normal function.

The Effect of Combination Use of Hemodialysis and Hemoperfusion on Microinflammation in Elderly Patients with Maintenance Hemodialysis

<b><i>Background:</i></b> Patients with maintenance hemodialysis (MHD) generally have a microinflammatory state. The aim of this study was to investigate the effects of hemodialysis (HD) combined with hemoperfusion (HP) on microinflammatory state in elderly patients with MHD. <b><i>Methods:</i></b> One hundred and fifty elderly patients with MHD were randomly divided into the control group and the observation group. The control group received simple HD treatment, and the observation group received combined HD + HP treatment on the basis of the control group. After 6 months of continuous treatment, the patients were evaluated to compare the quality of life, inflammation, adverse reactions, and nutritional indicators in the 2 groups before and after treatment. <b><i>Results:</i></b> There was no significant difference in the quality of life between the 2 groups before treatment. After treatment, the scores of psychological aspects, physiological aspects, social aspects, environmental aspects, and independent ability in the observation group were higher than those in the control group, with statistical significance (<i>p</i> &#x3c; 0.05). There was no statistical significance in the level of inflammation between 2 groups before treatment. After treatment, the levels of hs-CRP, Hcy, IL-6, and TNF-α in the observation group were significantly lower than those in the control group, with statistical significance (<i>p</i> &#x3c; 0.05). The incidence of dry mouth, skin reaction, neuritis, and subcutaneous tissue fibrosis in the observation group was lower than that in the control group, with statistical significance (<i>p</i> &#x3c; 0.05). There was no statistical significance in nutritional level indexes between 2 groups before treatment (<i>p</i>₁ &#x3e; 0.05). After treatment, the levels of hemoglobin, total protein, albumin, and transferrin in the observation group were significantly higher than those in the control group, with statistical significance (<i>p</i> &#x3c; 0.05). <b><i>Conclusion:</i></b> The clinical effect of HD combined with HP in elderly MHD patients is significant, which can effectively reduce the incidence of adverse reactions and inflammation in the patients and improve the quality of life and nutritional indicators of the patients.

Hemoadsorption corrects hyperresistinemia and restores anti-bacterial neutrophil function

Background

Mounting evidence suggests that sepsis-induced morbidity and mortality are due to both immune activation and immunosuppression. Resistin is an inflammatory cytokine and uremic toxin. Septic hyperresistinemia (plasma resistin >20 ng/ml) has been associated with greater disease severity and worse outcomes, and it is further exacerbated by concomitant acute kidney injury (AKI). Septic hyperresistinemia disturbs actin polymerization in neutrophils leading to impaired neutrophil migration, a crucial first-line mechanism in host defense to bacterial infection. Our experimental objective was to study the effects of hyperresistinemia on other F-actin-dependent neutrophil defense mechanisms, in particular intracellular bacterial clearance and generation of reactive oxygen species (ROS). We also sought to examine the effects of hemoadsorption on hyperresistinemia and neutrophil dysfunction.

Methods

Thirteen patients with septic shock and six control patients were analyzed for serum resistin levels and their effects on neutrophil migration. In vitro, following incubation with resistin-spiked serum samples, Pseudomonasaeruginosa clearance and ROS generation in neutrophils were measured. Phosphorylation of 3-phosphoinositide-dependent protein kinase-1 (PDPK1) was assessed using flow cytometry. In vitro hemoadsorption with both Amberchrome™ columns (AC) and CytoSorb® cartridges (CC) were used to test correction of hyperresistinemia. We further tested AC for their effect on cell migration and ROS generation and CC for their effect on bacterial clearance.

Results

Patients with septic shock had higher serum resistin levels than control ICU patients and showed a strong, negative correlation between hyperresistinemia and neutrophil transwell migration (ρ= − 0.915, p < 0.001). In vitro, neutrophils exposed to hyperresistinemia exhibited twofold lower intracellular bacterial clearance rates compared to controls. Resistin impaired intracellular signaling and ROS production in a dose-dependent manner. Hemoadsorption with AC reduced serum concentrations of resistin and restored neutrophil migration and generation of ROS to normal levels. Hemoadsorption with CC also corrected hyperresistinemia and reconstituted normal intracellular bacterial clearance.

Conclusions

Septic hyperresistinemia strongly correlates with inhibition of neutrophil migration in vitro. Hyperresistinemia itself reversibly impairs neutrophil intracellular bacterial clearance and ROS generation. Hemoadsorption therapy with a clinically approved device corrects hyperresistinemia and neutrophil dysfunction. It may therefore provide a therapeutic option to improve neutrophil function during septic hyperresistinemia and ultimately alleviate immunosuppression in this disease state.

Association between serum leptin levels and peritoneal dialysis: A meta-analysis

There is limited information available with regard to the association between serum leptin levels, or other adipokines, and serum lipid levels and insulin sensitivity in patients undergoing peritoneal dialysis (PD). Thus, the aim of the present study was to perform a meta-analysis investigating this association. Potential relevant studies were identified through searching the following databases: MEDLINE, Science Citation Index, Cochrane Library, PubMed, Embase, CINAHL, Chinese Biomedical, Chinese Journal Full-Text and Weipu Journal. Statistical analyses were calculated using version 12.0 STATA software. In total, 21 case-control studies comprising 1,187 subjects (574 patients and 613 controls) were collected for the meta-analysis. The results identified a statistically significant difference in the serum levels of leptin when comparing the PD patients with the healthy controls [controls vs. cases, standardized mean difference (SMD), 2.09; 95% confidence interval (CI), 1.58-2.59; P<0.001]. Furthermore, ethnicity-subgroup analysis indicated that the PD patients of Asian and Caucasian populations were associated with increased serum levels of leptin (Asian population, SMD, 2.05; 95% CI, 1.48-2.62; P<0.001; Caucasian population, SMD, 2.19; 95% CI, 1.19-3.18; P<0.001). Therefore, serum leptin levels may be used as a prognostic marker for PD.

Visceral adipose tissue is associated with insulin resistance in hemodialyzed patients

BACKGROUND

It has not been definitively established which factors affect insulin resistance (IR) and whether dialysis decreases IR. The aim of this study was to investigate factors that may have an influence on homeostasis model assessment (HOMA-IR) in hemodialyzed patients (HDpts) and to compare IR between HDpts and healthy subjects.

MATERIAL AND METHODS

We examined 33 HDpts and paired 33 subjects of the control group, matched for sex, age, and BMI. We analyzed concentrations of insulin, glucose, leptin, resistin, and total and high-molecular-weight adiponectin (HMWad) in serum. Using computed tomography in HDpts, we evaluated visceral adipose tissue (VAT), concentrations of visfatin, CRP, and IL-6.

RESULTS

HOMA-IR (median, 1.3 vs. 1.4, P=0.19), insulin (median 6.8 vs. 6.0 µIU/mL, P=0.7), glucose (79 mg/dL vs. 93 mg/dL, P=0.001). IR in HDpts is dependent on VAT (r=0.36, P=0.04) and this relationship is stronger than the relationship of BMI and IR (r=0.3, P=0.1). In HDpts we found higher concentrations of leptin (P=0.001) and resistin (P<0.001), with no relation to IR. HMWad and its percentage in relation to total adiponectin are higher in HDpts (P=0.03 and P<0.001, respectively).

CONCLUSIONS

HOMA-IR in HDpts does not differ from the control group. In HDpts it depends on the quantity of VAT and this relationship is stronger than with BMI. In HDpts leptin and resistin do not influence IR. HMWad and its percentage in total adiponectin are significantly higher in HDpts.

The peptidic middle molecules: is molecular weight doing the trick?

Chronic kidney disease (CKD) is characterized by a gradual endogenous intoxication caused by the progressive accumulation of bioactive compounds that in normal conditions would be excreted and/or metabolized by the kidney. Uremic toxicity now is understood as one of the potential causes for the excess of cardiovascular disease and mortality observed in CKD. An important family of uremic toxins is that of the peptidic middle molecules, with a molecular weight ranging between 500 and 60,000 Da, which makes them, as a consequence, difficult to remove in the process of dialysis unless the dialyzer pore size is large enough. This review provides an overview of the main and best-characterized peptidic middle molecules and their role as potential culprits of the cardiometabolic complications inherent to CKD patients.

A longitudinal study of nutritional and inflammatory status in patients on dialysis

OBJECTIVE

Several anthropometric, laboratory and bioelectrical impedance parameters of nutritional status and inflammation are often used as prognostic indices in patients on dialysis. Their longitudinal assessment is necessary for the estimation of their true prognostic value. We aim to estimate this prognostic value in better-nourished dialysis patients, which are commonly under-represented in pertinent studies.

METHODS

The design is a prospective case series. Pertinent parameters were studied three times during a 20-month period in 47 haemodialysis (HD) and 27 peritoneal dialysis (PD) patients with a low malnutrition-inflammation score (MIS). Mortality rate was assessed three years after the initial evaluation. Correlation coefficients were calculated between mortality rate, the studied parameters and their alteration.

RESULTS

Serum albumin of less than 40 g/l was strongly correlated with mortality risk. The alteration of studied parameters during a short period of time does not allow for long-term prediction of mortality risk.

CONCLUSION

Serum albumin had the strongest predictive value of all the pertinent parameters in the study. Thus, better conjugate clinical and laboratory measurements should be developed for patients on PD, as well as for those with a relatively low MIS.

Leptin in chronic kidney disease: a link between hematopoiesis, bone metabolism, and nutrition

Anemia, dyslipidemia, malnutrition, together with mineral and bone disorders are common complications in patients with chronic kidney disease (CKD). All are associated with increased risk of mortality. Leptin is a small peptide hormone that is mainly but not exclusively produced in adipose tissue. It is also secreted by normal human osteoblasts, subchondral osteoblasts, placental syncytiotrophoblasts, and the gastric epithelium. Leptin binds to its receptors in the hypothalamus to regulate bone metabolism and food intake. Leptin also has several other important metabolic effects on peripheral tissues, including the liver, skeletal muscle, and bone marrow. Leptin is cleared principally by the kidney. Not surprisingly, serum leptin appears to increase concurrently with declines in the glomerular filtration rate in patients with CKD. A growing body of evidence suggests that leptin might be closely related to hematopoiesis, nutrition, and bone metabolism in CKD patients. Results are conflicting regarding leptin in patients with CKD, in whom both beneficial and detrimental effects on uremia outcome are found. This review elucidates the discovery of leptin and its receptors, changes in serum or plasma leptin levels, the functions of leptin, relationships between leptin and the complications mentioned above, and pharmaceutical interventions in serum leptin levels in patients with CKD.

Vitamin D deficiency, insulin resistance, serum adipokine, and leptin levels in peritoneal dialysis patients

OBJECTIVE

Associations between 25 hydroxy vitamin D [25(OH)D], adipokines levels, and insulin resistance have been reported. The aim of this study was to explore the effects of cholecalciferol supplementation on vitamin D levels, insulin resistance, leptin, and adiponectin levels in vitamin D-deficient peritoneal dialysis (PD) patients.

METHODS

In nineteen vitamin D-deficient PD patients, who were treated with cholecalciferol, fasting serum glucose, insulin, adiponectin, leptin, 25(OH)D and parathyroid hormone (PTH) were measured before and after cholecalciferol replacement therapy. Eighteen (94.7 %) PD patients with vitamin D deficiency were receiving active vitamin D compounds (alphacalciferol) for PTH control. Alphacalciferol dosing was kept constant during treatment with cholecalciferol.

RESULTS

While mean 25(OH)D significantly increased from (10.2 ± 4.9 ng/ml) to (82.9 ± 56.5 ng/ml) (p < 0.05), mean homeostatic model assessment-insulin resistance index significantly decreased from (4.6 ± 3.6) to (2.8 ± 2.0) after cholecalciferol replacement therapy (p < 0.05). Serum leptin levels (12.9 ± 17.6 ng/ml) significantly increased (18.1 ± 19.5 ng/ml) (p < 0.05), while there was no change in serum adiponectin, calcium, and phosphate after vitamin D replacement. Serum PTH levels significantly decreased from 551.9 ± 276.6 pg/ml to 434.0 ± 273.4 ng/ml.

CONCLUSIONS

Cholecalciferol replacement therapy significantly decreases PTH levels and insulin resistance. The results of this study need to be confirmed in larger clinical trials.

Low resistin level is associated with poor hospitalization-free survival in hemodialysis patients

Malnutrition and inflammation are related to high rates of morbidity and mortality in hemodialysis patients. Resistin is associated with nutrition and inflammation. We attempted to determine whether resistin levels may predict clinical outcomes in hemodialysis patients. We conducted a prospective evaluation of 100 outpatients on hemodialysis in a single dialysis center (male, 46%; mean age, 53.7 ± 16.4 yr). We stratified the patients into 4 groups according to quartiles of serum resistin levels. During the 18-month observational period, patients with the lowest quartile of serum resistin levels had poor hospitalization-free survival (log rank test, P = 0.016). After adjustment of all co-variables, patients with the lowest quartile of serum resistin levels had poor hospitalization-free survival, compared with reference resistin levels. Higher levels of interleukin-6 were an independent predictor of poor hospitalization-free survival. In contrast, serum resistin levels were not correlated with interleukin-6 levels. The current data showed that low resistin levels may independently predict poor hospitalization free survival in hemodialysis patients.

Low circulating adiponectin levels are associated with insulin resistance in non-obese peritoneal dialysis patients

In patients with end-stage renal disease (ESRD), circulating adipokine levels are increased due to decreased renal clearance, irrespective of obesity. However, whether adipokines play a role in the development of insulin resistance (IR) in non-obese ESRD patients is unknown. We conducted a cross-sectional study to identify factors associated with IR in 62 non-obese patients on peritoneal dialysis (PD). Non-obesity was defined as body mass index (BMI) <25 kg/m(2). IR was determined using homeostatic model assessment-IR (HOMA-IR). We also measured serum concentrations of adiponectin, leptin, resistin, high-sensitivity C-reactive protein (hsCRP), and IL-6. The average BMI of the study patients was 21.6 kg/m(2). When patients were divided into two groups according to the median value of HOMA-IR, serum adiponectin levels were significantly lower in patients with HOMA-IR > 1.85 than in those with HOMA-IR ≤1.85, whereas serum concentrations of leptin and resistin did not differ between the two groups. In addition, log-transformed HOMA-IR was negatively correlated with adiponectin (γ = -0.464, P < 0.001) and log-transformed high-density lipoprotein cholesterol (γ = -0.250, P = 0.050) and positively correlated with age (γ = 0.334, P = 0.008) and triglyceride (γ = 0.392, P = 0.002). However, resistin, log-transformed leptin and log-transformed hsCRP were not associated with HOMA-IR. In a multiple linear regression model, adiponectin was independently associated with HOMA-IR (β = -0.023, P = 0.015). In conclusion, this study suggests that low circulating adiponectin levels might be involved in IR even in non-obese patients undergoing PD.

Resistin levels in lupus and associations with disease-specific measures, insulin resistance, and coronary calcification

OBJECTIVE

To evaluate levels of resistin in female subjects with systemic lupus erythematosus (SLE) compared to age and race-matched controls and to determine the relationship between resistin and systemic inflammation, disease measures, and coronary artery calcification (CAC).

METHODS

Resistin levels were measured on stored samples from 159 women with SLE and 70 controls as an extension of a previous cross-sectional study. Spearman correlations and multivariable regressions were used to examine whether resistin levels were associated with SLE, disease-specific and inflammatory markers, insulin resistance, and CAC.

RESULTS

In a multivariable linear regression model, a diagnosis of SLE was significantly associated with higher resistin levels independent of age, race, renal function, body mass index (BMI), high-sensitivity CRP (hsCRP), hypertension, diabetes, and steroid use. In SLE, resistin levels correlated positively with Systemic Lupus International Collaborating Clinics Damage Index, glomerular filtration rate (GFR), hsCRP, erythrocyte sedimentation rate, homocysteine, and disease duration (all p < 0.03). Resistin level did not correlate with markers of insulin resistance or body adiposity, including homeostatic model assessment or BMI. Resistin levels were significantly elevated in SLE cases with CAC compared to cases without CAC (16.58 vs 13.10 ng/ml, respectively; p = 0.04). In multivariate logistic regression, the association was not present after adjustment for age, race, and GFR.

CONCLUSION

SLE was independently associated with higher resistin levels. Among subjects with SLE, higher resistin level correlated positively with renal dysfunction, inflammatory markers, and disease damage but not with insulin resistance or BMI. SLE cases with CAC had higher resistin levels than cases without CAC; however, this relationship was dependent on other established risk factors.

Fasting serum leptin level correlates with mid-arm fat area in peritoneal dialysis patients

Leptin correlates with body fat content and plays a pivotal role in inflammatory response. This study aimed to investigate the relationships of fasting serum leptin levels and the anthropometric fat components among peritoneal dialysis (PD) patients. Fasting blood samples were obtained from 40 PD patients. Leptin levels were measured using a commercial enzyme-linked immunosorbent assay kit. Body weight (r=0.424; P=0.006), waist circumference (r=0.352; P=0.026), body mass index (BMI; r=0.483; P=0.002), body fat mass (r=0.352; P=0.026), high sensitivity C-reactive protein (hs-CRP; r=0.494; P=0.001), triceps skinfold thickness (TSF; r=0.505; P=0.001), mid-arm circumference (MAC; r=0.471; P=0.002), and mid-arm fat area (MAFA; r=0.564; P<0.001) were positively correlated, while high density lipoprotein (HDL)-cholesterol (r=-0.345; P=0.028) was negatively correlated with fasting serum leptin levels among the PD patients. Multivariate forward stepwise linear regression analysis showed that MAFA (R(2)=0.318, P=0.011) was the independent predictor of fasting serum leptin levels among the PD patients. In conclusion, fasting leptin level was positively associated with body fat composition (body weight, waist circumference, BMI, body fat mass, TSF, MAC, and MAFA) and hs-CRP among PD patients, and MAFA was the independent predictor of fasting serum leptin levels among the PD patients.

Correlates of insulin resistance in older individuals with and without kidney disease

BACKGROUND

Chronic kidney disease (CKD) is associated with insulin resistance (IR). Prior studies have found that in individuals with CKD, leptin is associated with fat mass but resistin is not and the associations with adiponectin are conflicting. This suggests that the mechanism and factors associated with IR in CKD may differ.

METHODS

Of the 2418 individuals without reported diabetes at baseline, participating in the Health, Aging and Body Composition study, a study in older individuals aged 70-79 years, 15.6% had CKD defined as an estimated glomerular filtration rate (eGFR) <60 mL/min/1.73 m(2) based on cystatin C. IR was defined as the upper quartile of the homeostasis model assessment. The association of visceral and subcutaneous abdominal fat, percent body fat, muscle fat, lipids, inflammatory markers and adiponectin were tested with logistic regression. Interactions were checked to assess whether the factors associated with IR were different in those with and without CKD.

RESULTS

Individuals with IR had a lower eGFR (80.7 ± 20.9 versus 75.6 ± 19.6, P < 0.001). After multivariable adjustment, eGFR (odds ratio per 10 mL/min/1.73 m(2) 0.92, 95% confidence interval 0.87-0.98) and CKD (1.41, 1.04-1.92) remained independently associated with IR. In individuals with and without CKD, the significant predictors of IR were male sex, black race, higher visceral fat, abdominal subcutaneous fat and triglycerides. In individuals without CKD, IR was associated with lower high-density lipoprotein and current nonsmoking status in multivariate analysis. In contrast, among individuals with CKD, interleukin-6 (IL-6) was independently associated with IR. There was a significant interaction of eGFR with race and IL-6 with a trend for adionectin but no significant interactions with CKD (P > 0.1). In the fully adjusted model, there was a trend for an interaction with adiponectin for eGFR (P = 0.08) and significant for CKD (P = 0.04 ), where adiponectin was associated with IR in those without CKD but not in those with CKD.

CONCLUSIONS

In mainly Stage 3 CKD, kidney function is associated with IR; except for adiponectin, the correlates of IR are similar in those with and without CKD.

Proinflammatory cytokines, hepatocyte growth factor and adipokines in peritoneal dialysis patients

Chronic inflammation is a well-recognized complication in dialysis patients and a potential role of the adipose tissue as an important tissue of origin contributing to inflammation has been proposed. Stable peritoneal dialysis (PD) patients were enrolled to investigate the relationship between serum levels of proinflammatory cytokines and adipokines. Our results revealed that there was a strong association between high sensitivity C-reactive protein and interleukin (IL)-6 and tumor necrosis factor-alpha (TNF-alpha) but not with IL-10 and IL-18. IL-6 correlated with TNF-alpha, IL-10, and IL-18. No association was found between IL-10 and IL-18. Adiponectin was positively correlated with all proinflammatory cytokines, except IL-10. No significant association was found between resistin and proinflammatory cytokines. Hepatocyte growth factor (HGF) was directly related to proinflammatory cytokines but not with adipokines. The presence of residual kidney function (RKF) affected IL-6, TNF-alpha, and HGF levels. The peritoneal transport property did not influence inflammatory cytokine and adipokine levels. In conclusion, there was a close relationship between proinflammatory cytokines and adipokines. HGF correlated with proinflammatory cytokines but not with adipokines. The PD-related factors such as RKF, peritoneal property and dialysis glucose load affected levels of proinflammatory cytokines. Body mass index was an important determinant of leptin and adiponectin in PD patients.

Peritoneal adipocytes and their role in inflammation during peritoneal dialysis

Adipose tissue is a major site of chronic inflammation associated with peritoneal dialysis (PD) frequently complicating peritonitis. Adiposity-associated inflammation plays a significant contributory role in the development of chronic inflammation in patients undergoing maintenance PD. However, the molecular and cellular mechanisms of this link remain uncertain. Adipose tissue synthesizes different adipokines and cytokines that orchestrate and regulate inflammation, insulin action, and glucose metabolism locally and systemically. In return, inflammation retards adipocyte differentiation and further exacerbates adipose dysfunction and inflammation. An understanding of the inflammatory roles played by adipose tissue during PD and the healing mechanism of injured mesothelium will help to devise new therapeutic approach to slow the progression of peritoneal damage during peritoneal dialysis. This article reviews the roles of peritoneal adipose tissue in chronic peritoneal inflammation under PD and in serosal repair during PD.

Resistin as a cardiovascular and atherosclerotic risk factor and uremic toxin

Resistin is a 12.5 kDa protein originally found to be secreted by mouse adipocytes. Whereas in rodents adipose tissue is the main source of resistin, in humans resistin is expressed primarily in macrophages. In a variety of pathophysiologic states, particularly in type 2 diabetes mellitus and in chronic kidney disease, the serum concentration of resistin is increased. Resistin reduces the glucose uptake in adipose tissue and skeletal muscle cells and may be involved in insulin resistance. A positive correlation between resistin levels and inflammatory markers has been described. Resistin has a potential role in cardiovascular disease and may contribute to an increased atherosclerotic risk by modulating the activity of endothelial cells. We recently found that resistin in concentrations measured in uremia is able to interfere with the chemotactic movement and the oxidative burst of neutrophils, cells of the first-line nonspecific immune defense. Therefore, resistin may also contribute to the disturbed immune response and as a consequence to the increased risk of infections in uremic and diabetic subjects.

Circulating adipokines and the protective effects of hyperinsulinemia in inflammatory bowel disease

OBJECTIVE

Adipokines are fat-derived hormones and cytokines with immune-modulating and metabolic properties. Most of them are associated with insulin resistance. The aim of the present investigation was to evaluate circulating levels of adipokines and glucose homeostasis in patients with inflammatory bowel disease (IBD) and to evaluate possible associations with the course and characteristics of the disease.

METHODS

Serum leptin, resistin, visfatin, retinol-binding protein-4, adiponectin, glucose, insulin, and inflammatory parameters were analyzed in 93 patients with inactive IBD (49 with Crohn's disease [CD], 44 with ulcerative colitis [UC]), 35 patients with active IBD (18 with CD, 17 with UC), and 37 age- and body mass index-matched healthy controls. Ninety-two patients were followed for 6 mo.

RESULTS

Leptin was similar in patients with IBD and controls, whereas resistin and visfatin were increased in patients with active disease but not in those in remission. In active and inactive disease, adiponectin was decreased (P < 0.001) and retinol-binding protein-4 was increased (P < 0.001) compared with controls. About 60% of patients with IBD showed increased levels of insulin, whereas serum glucose remained normal, resulting in increased homeostasis model assessment values in most patients. Hyperinsulinemia was associated with the decrease in adiponectin (r = -0.572, P < 0.001) and proved to be an independent protective factor for 6-mo maintenance of remission (P = 0.016).

CONCLUSION

IBD led to largely similar alterations in circulating adipokines and hyperinsulinemia in patients with CD and those with UC. The unexpected protective effect of hyperinsulinemia on relapse rate denotes the role of the metabolic-inflammatory response as a modulator in IBD.