Serum Leptin Levels In Patients Research Articles

Evaluation of Serum Leptin Level in Psoriasis Patients and its Relation with the Severity of Disease

Background and Objective: The association of leptin with psoriasis is currently controversial. The purpose of this study was to evaluate serum leptin levels in patients with psoriasis and its relationship with the severity of the disease. Materials and Methods: In this case-control study, serum leptin levels were measured in 40 patients with psoriasis and 40 age- and gender-matched healthy controls by sandwich enzyme-linked immunosorbent assay method. The severity of psoriasis was assessed by the Psoriasis Area and Severity Index (PASI). Data were analyzed using SPSS software version 16. Results: Of 40 patients, 35 (87.5%) had plaque psoriasis, 3 (7.5%) had palmo-plantar, and one of the remaining two patients had erythrodermic psoriasis while the other one had a pustular type. The mean disease severity based on PASI was 10.2 with a range of 0.8 to 39.9. The most common sites of involvement were generalized (27.5%), upper and lower extremities together (20.0%), lower extremities alone (15%), and trunk and lower extremities (15%) in descending order. Leptin was higher in the patient group than the control group (19.2±16.3 ng/ml versus 15.5±16.1 ng/ml) (P=0.227). The correlation between leptin and body mass index was positive and significant in both groups. No significant relationship was found between the severity and duration of disease and leptin. Conclusion: The findings of this study showed that similar to most studies, serum leptin levels were higher in patients with psoriasis than in healthy subjects, and in obese people, this difference was greater than in normal-weight individuals

Association of Serum Leptin Levels in Patients with Chronic Periodontitis and Cardiovascular Diseases

Background: In recent years, clinical studies have shown an association between leptin and periodontal disease. The present study aimed to estimate and compare the serum leptin levels in chronic periodontitis patients with cardiovascular diseases. Materials and Methods: A total of 30 subjects were included in the study and are divided into three groups, i.e. Group 1: ten healthy subjects, Group 2: ten subjects with chronic periodontitis, and Group 3: ten subjects with periodontitis and cardiovascular disease. Two millimeters of the venous blood sample was collected from the antecubital fossa of all the sixty subjects under aseptic conditions. Serum was obtained from the blood by centrifuging at 2500 rpm for 10 min. Now, this collected serum is used to estimate leptin using a leptin enzyme-linked immunosorbent assay (ELISA) kit (Clementia biotech). Leptin levels were assessed in an ELISA reader. Statistical analysis was conducted using SPSS software version 24. Results: A significant correlation was observed with serum leptin levels and clinical parameters in the chronic periodontitis + cardiovascular disease group, i.e. plaque index (r = −0.96, P = 0.0003*), gingival index (r = −0.89; P = 0.0005*), probing depth (r = −0.82; P = 0.003*), and clinical attachment level (r = −0.84; P = 0.001*) * is Statistically Significant. Conclusion: The study found a statistically significant increase in serum leptin levels in the Group III compared to Groups II and I which suggest an increase in inflammatory state increases the serum levels of leptin.

Serum leptin levels in patients with chronic kidney disease and hypertensive heart disease: An observational cross‐sectional study

Adipocytes secrete a peptide hormone called leptin, which plays a crucial role in controlling appetite and energy expenditure. Alterations in leptin concentrations are associated with CKD-related cardiovascular problems such as hypertensive heart disease (HHD). Despite the link, data on the precise function of leptin in people with CKD and HHD is scant. An observational cross-sectional study involving a total of 108 participants (72 CKD patients with HHD and 36 healthy controls). Their demographic and anthropometric information was collected using a standardized questionnaire. Certain clinical measures such as blood pressure and body mass index (BMI) were assessed. Fasting blood samples were analyzed for levels of plasma glucose (FPG), lipids, creatinine, and leptin. Data were analyzed with SPSS v23. Leptin, FPG, creatinine and triglyceride levels were all significantly higher in CKD patients with HHD compared to controls (p < 0.01 for all). Furthermore, advanced CKD status (being in stage 5), having a 6-year diagnosis of HHD, being female, having a higher BMI, and elevation in levels of HDL and FPG contributed significantly to the variance in serum leptin levels in the case group (β = 0.37, 0.22, 0.19, 0.18, 0.27, 0.28; p < 0.05 for all). In the control group, the female gender had the biggest unique effect on circulating leptin levels, followed by BMI and eGFR (β = 0.71, 0.34, -0.22; p < 0.01 for all). Patients with CKD who also had HHD reported considerably higher circulating leptin levels. Significantly higher blood leptin levels were shown to be associated with CKD stage 5 in the case group. These results are consistent with the role of leptin in the metabolic complexity seen in CKD patients. There needs to be more research into treatments that aim to lower leptin levels in CKD patients with HHD.

Role Of Serum Leptin Levels In Patients With Metabolic Syndrome In A Tertiary Care Hospital In South India

Role Of Serum Leptin Levels In Patients With Metabolic Syndrome In A Tertiary Care Hospital In South India

Effect of Leptin Levels of Type 2 Diabetes Mellitus and Diabetic Complications.

To investigate serum leptin levels in patients with type 2 diabetes mellitus (T2DM) and the relationship between leptin levels and T2DM complications and prevalence. A total of 355 patients, 282 cases with T2DM and 73 normal controls, were recruited at 1st Medical Centre, Chinese PLA General Hospital (Beijing, China) between November 2013 and July 2014. Levels of serum leptin, biochemical markers and sexual hormones were measured, and clinical characteristics were retrieved through the electronic medical record system. Leptin levels in females were higher than that in males. Leptin levels in T2MD patients were positively correlated with body mass index, percent body fat, triglyceride, cystatin C homocysteine and salivary acid, and negatively correlated with glycosylated serum protein and glycosylated albumin levels. Leptin levels in males were positively correlated with systolic pressure and estradiol, and negatively correlated with testosterone and high density lipoprotein cholesterol. Sex (female) was positively correlated with the duration of disease. Leptin levels in T2DM patients with complications such as hypertension, diabetic nephropathy, diabetic peripheral neuropathy and coronary heart disease were higher than that in patients without such complications. Leptin levels in females with diabetic retinopathy and diabetic macroangiopathy were higher than that in patients without such complications, but there was no difference in males. Leptin has significant gender differences. Leptin levels are related to body mass index, percent body fat and sex hormone level in T2DM patients and may affect short-term blood glucose control in T2DM patients. Leptin levels are related to complications in patients with T2DM and affect the prevalence rates of complications.

Serum leptin levels in children and adolescents with spinal muscular atrophy types 2 and 3✰

AimIt has been reported that in patients with spinal muscular atrophy (SMA), lower levels of motor function are associated with hyperleptinemia. Additionally, hyperleptinemia has been found to be more frequent in underweight SMA patients. Therefore, we aimed to analyze serum leptin levels in patients with SMA. MethodThis was a cross-sectional study of pediatric patients (2–19 years old) with SMA types 2 and 3. The investigations included anthropometric measurements, assessment of pubertal status, motor function evaluation using the Hammersmith Functional Motor Scale – Expanded (HFMSE), and serum leptin levels. ResultsIn total, 37 patients (22 with type 2 and 15 with type 3 SMA) were included in the study. The male-to-female ratio was 1:1.3 and 62.2% of patients were prepubertal. No statistically significant correlation was found between the HFMSE score and leptin levels, rs(35) = 0.24, p = 0.15. There was, however, a strong positive relationship between the body mass index (BMI) z-score and leptin levels, rs(35) = 0.87, p < 0.001. ConclusionSerum leptin levels do not seem to be a useful marker of disease severity in children and adolescents with types 2 and 3 SMA. As in the general pediatric population, leptin levels are strongly correlated with BMI, which is a surrogate measure of body fat.

Effect of Gender on Serum Leptin in Type 2 Diabetes Mellitus: A System Review and Meta-Analysis.

Objective To assess the effect of gender factors on serum leptin levels in patients with diabetes mellitus. Methods To remove any studies that indicated a relationship between leptin-based inflammatory variables and the prevalence of type 2 diabetes in particular patient categories, a comprehensive search of all articles published between July 2019 and June 2021 was performed on PubMed/MEDLINE, Web of Science, Scopus, and EBSCO Host, including Academic Search Premier, Africa-Wide Information, and Cumulative Index to Nursing and Allied Health Literature. A summary description of the combined analysis across multiple centers, regions, and continents will help us better understand the effect of gender on serum leptin levels in patients with diabetes. The meta-analysis was performed using RevMan 5.2 software on the literature that satisfied the inclusion and exclusion criteria. Results Plasma CRP levels in women with type 2 diabetes were found to be no different from those in males with type 2 diabetes, with an OR of 0.12, 95 percent confidence interval (CI) of 0.12 to 0.12, P = 0.01. There was no statistically significant difference in the plasma level of interleukin-6 (IL-6) between women with type 2 diabetes and males with type 2 diabetes However, the “inverted funnel” diagram is asymmetrical, indicating a publication bias in the included studies, despite the fact that there was no statistically significant difference in abnormal leptin levels between men with type 2 diabetes and women patients (OR = −0.69, 95 percent CI (0.88, 1.00), P < 0.05). Conclusion Gender factors did not affect the level of inflammatory factors and leptin level in type 2 diabetes.

Novel Marker for Premature Ejaculation: Serum Leptin Level.

BackgroundLeptin, which was only discovered in humans in 1994, has recently been shown to have a possible link with premature ejaculation.AimTo evaluate whether serum leptin levels differed between patients with premature ejaculation and healthy men, and to analyze the changes in leptin levels before and after treatment.MethodsSix studies assessing the relationship between leptin and premature ejaculation published up to October 2021 were identified from multiple databases (PubMed, Web of Science, Cochrane) and the data were analyzed by Stata software.OutcomesDifferences in leptin levels in premature ejaculation patients and healthy people, and changes of leptin levels in premature ejaculation population before and after treatment.ResultsAnalysis of studies assessing differences in leptin concentrations between patients with PE and healthy men showed that there was a statistically significant difference in leptin levels between PE patients and controls (WMD (95% CI) = 17.89 (8.64, 27.14), P < .001). On the other hand, the analysis of data from 3 studies describing serum leptin levels in PE patients before and after treatment with selective serotonin reuptake inhibitors (SSRIs) showed that there was a significant decrease with leptin levels in PE patients after treatment (WMD (95%CI) = 22.06 (17.21, 26.92), P < .001).Clinical ImplicationsIt is possible that leptin can be used as a new marker for premature ejaculation.Strength & LimitationsThe strength of this study is that it is the first meta- analysis to assess the differences of serum leptin levels between patients with premature ejaculation and healthy subjects and the changes of leptin levels before and after treatment in patients with premature ejaculation. A major limitation is that a greater heterogeneity was identified through our analysis, however we did not find a definitive source of heterogeneity.ConclusionThere was a statistically significant relationship between serum leptin levels and patients with PE. In addition, serum leptin levels in patients with PE decreased significantly after 8 weeks of treatment with SSRIs.Liu G, Zhang Y, Zhang W, et al. Novel Marker for Premature Ejaculation: Serum Leptin Level. Sex Med 2022;10:100509.

Effect of resistance exercise on serum leptin levels in a prospective longitudinal study of women patients with rheumatoid arthritis

BackgroundExercise has an anti-inflammatory effect and reduces fat mass. Leptin has been known to be proinflammatory adipokines mainly produced by adipocytes. However, few studies have investigated the association between exercise and changes in serum leptin levels of patients with RA. This study evaluated the effect of an individualized resistance exercise on inflammatory markers including leptin as well as muscle strength and exercise capacity in patients with rheumatoid arthritis (RA).MethodsA total of 42 age- and sex-matched participants were assigned to a resistance exercise program (60 min, once a week for 12 weeks, and self-exercise twice a week) or to a control group. Muscle strength, exercise capacities, and inflammatory markers such as cytokines and adipokines were assessed at baseline and at 12 weeks follow-up. Longitudinal changes in muscle strength, exercise capacity, cytokines, and adipokines between groups were tested with repeated measures analysis of variance or using the generalized estimating equation, with adjustment for baseline disease activity score 28-C response protein as a covariate.ResultsA total of 37 of 42 female patients with RA completed this prospective intervention study. Grip strength improved significantly in the exercise group (P < 0.05), while no between-group changes were found. Quadriceps contraction power (P for group-time interaction = 0.035 for the right side and P for group-time interaction = 0.012 for the left side) and 6-minute walking distance (P for group-time interaction = 0.021) were all improved significantly in the exercise group compared with the control group. In addition, serum leptin levels were significantly decreased in the exercise group compared with the control group (P for group-time interaction = 5.22 × 10−5), but not the other cytokines or adipokines. The change in serum leptin levels correlated with the changes in fat mass (Rho = 0.491, P= 0.015) and visceral fat area (Rho = 0.501, P= 0.013).ConclusionIn addition to muscle strength and exercise capacity, the 12 weeks of individualized resistance exercise reduced serum leptin levels in keeping with body fat mass or visceral fat area, suggesting that serum leptin levels might be a surrogate marker of exercise in RA.

Elevated Serum Leptin Levels as a Predictive Marker for Polycystic Ovary Syndrome.

BackgroundLeptin may have important implications in polycystic ovary syndrome (PCOS)-related metabolic disorders. However, the changes in serum leptin levels in patients with PCOS and its predictive value for PCOS remain obscure. We intend to analyze the association between leptin and PCOS in this study.Materials and MethodsThe study comprised 89 patients with PCOS and 139 individuals without PCOS. Each group was stratified as either normal- or hyper-fasting serum insulin (FSI), and lean or overweight/obese; and the patients were further categorized as normal- or hyper-androgenic. The validity of leptin toward the diagnosis of PCOS, or leptin combined with total testosterone, dehydroepiandrosterone sulfate (DHEAS), and free testosterone was estimated by receiver operating characteristic (ROC) curves, and correlations between paired variables was estimated by Spearman’s rank correlation coefficient. Associations between the clinical and metabolic variables and PCOS were analyzed via logistic regression.ResultsThe serum leptin levels of patients with PCOS were significantly higher than that of the control, and especially the PCOS in hyper-FSI, hyperandrogenimic and overweight/obese subgroups. The area under the ROC curve (AUC) of leptin was 74%, with cutoff value, sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) 11.58 ng/mL, 77.5%, 62.6%, 57.0%, and 81.3%, respectively. Combined leptin and anti-Müllerian hormone (AMH) had the highest AUC (92.3%), excellent sensitivity (93.3%), moderate specificity (78.3%), PPV (73.5%) and NPV (94.8%). Serum leptin levels of the patients were correlated with the FSI, fasting plasma glucose (FPG), homeostasis model assessment of insulin resistance (HOMA-IR), body mass index (BMI), and total testosterone levels. Elevated serum leptin was associated with a high risk of PCOS [P = 0.015; OR (95% CI) 1.128 (1.024–1.244)].ConclusionSubstantially elevated serum leptin is significantly associated with PCOS. These findings warrant further investigations into the function of leptin in the pathogenesis of PCOS.

Elevated Serum Leptin Levels in Patients With Eosinophilic Chronic Rhinosinusitis.

Background: Eosinophilic chronic sinusitis (ECRS) is a subtype of CRS with nasal polyps (CRSwNP) that is frequently comorbid with asthma. Notably, ECRS patients often show a high recurrence of NPs after surgical resection. Leptin is a hormone produced by adipocytes that has been implicated in airway inflammatory diseases. However, to date, the role of leptin in ECRS has not been investigated. Objective: To determine whether the serum levels of leptin are altered in patients with ECRS. Methods: In total, 40 patients with ECRS, 15 patients with non-eosinophilic CRS (non-ECRS), and 12 individuals without CRS (control) were included in this study. Patient’s serum leptin levels were assessed, and the number of eosinophils in their NPs were measured through a histological evaluation of the three densest areas with cellular infiltrate beneath the epithelial surface. Finally, nasal fibroblast cultures established from NPs were stimulated with varying concentrations of recombinant leptin in vitro to determine whether leptin affects eotaxin-3 (Chemokine (C-C motif) ligand 26 :26: CCL26) expression. Results: The serum leptin levels in both the ECRS and non-ECRS groups were significantly higher than those in the control subjects (p < 0.0001 vs. ECRS; p < 0.05 vs. non-ECRS). Furthermore, ECRS patients displayed significantly elevated serum leptin levels compared to non-ECRS patients (p < 0.001), although there was no difference in body mass index between the groups. Notably, serum leptin levels were correlated with the proportion of eosinophils in peripheral blood (r = 0.3575, p < 0.01) and the number of eosinophils in NPs (r = 0.5109, p < 0.0001). Serum leptin levels were also correlated with eotaxin-3 mRNA expression in NPs (r = 0.5374, p < 0.01). Finally, leptin significantly augmented eotaxin-3 expression in nasal fibroblasts established in vitro from NPs in a leptin receptor-dependent manner (p < 0.05). Conclusion: Leptin levels are elevated in ECRS patients and may both promote and indicate the severity of ECRS as well as systemic type 2-biased inflammatory responses. Combined, these data indicate that circulating leptin may play a significant role in the development of eosinophilic inflammation in NPs.

SERUM LEPTIN LEVEL IN BREAST CANCER.

Leptin is a polypeptide which is mostly produced in white fat tissue and is an important proinflammatory, proangiogenic, proinvasive and mitotic factor. There is ever more evidence suggesting the key role of leptin in the occurrence of breast cancer. The aim of the study was to investigate serum leptin levels in patients with benign breast tumors, as well as in various breast cancer phenotypes, taking into account leptin levels connected to menopausal status and body mass index (BMI). The study included 97 patients having their breast tumor surgically removed. Serum leptin level was determined by ELISA method in all study patients. Study results showed that significantly more women, regardless of having malignant or benign tumors, were postmenopausal and had a significantly higher level of leptin compared to the premenopausal group. The highest level of leptin was recorded in the group of postmenopausal obese women compared to other postmenopausal women but also compared to premenopausal women. According to BMI alone, obese women had a significantly higher level of leptin regardless of the type of tumor. The most significant differences in leptin levels observed through BMI were found in the Luminal B1 group. In conclusion, serum leptin level was shown to be a good diagnostic parameter suggesting a higher possibility of breast cancer development.

Alterations of Serum Leptin Levels in Patients with Autoimmune Thyroid Disorders.

Background: Thyroid dysfunction is accompanied with significant metabolic alterations that affect body weight, appetite, and energy expenditure, as well as lipid and carbohydrate metabolism. Leptin, an adipokine produced by adipocytes, regulates food intake and energy storage. Thyroid hormones and leptin share some physiological effects. Changes in leptin have been shown in patients with dysfunction of the thyroid; however, the results are contradictory. The aim of this study was to evaluate the circulating levels of leptin in patients with Graves disease (GD) and Hashimoto thyroiditis (HT) before and after normalization of thyroid function compared with the control group. Methods: Newly diagnosed adult patients with GD, HT, and healthy euthyroid controls were recruited. Various clinical and biochemical parameters, including thyroid function tests and serum leptin level, were assessed before and after treatment and compared between groups. Results: Data from 56 patients with HT, 54 patients with GD, and 54 healthy controls were analyzed. Serum leptin levels of patients with HT (30.96 ± 3.88 ng/mL) were found to be significantly higher than the controls (22.35 ± 4.72 ng/mL) (p<0.001), whereas patients with Graves had lower serum leptin levels (14 ± 4.54 ng/mL) (p<0.001). In patients with HT, serum leptin levels showed a significant decrease after treatment (31 vs 27 ng/mL; p<0.001), while in patients with GD, leptin increased significantly after treatment (14 vs 17 ng/mL; p<0.001). Conclusion The present study showed that serum leptin levels increased in patients with HT and decreased in those with GD than the control group. However, after treatment, leptin decreased in the Hashimoto group and increased in the Graves group, although it was still significantly different from the control group.

Promoter Methylation of LEP and LEPR before and after Bariatric Surgery: A Cross-Sectional Study

Introduction: DNA methylation constitutes one important epigenetic mechanism that regulates gene expression in human cells. With regard to obesity, bariatric surgery-induced weight loss has been associated with promoter methylation changes in several genes. Hyperleptinemia is a characteristic feature of obesity. The underlying regulating mechanisms have not yet been completely elucidated. Methods: We investigated the methylation of the promoters of the leptin gene (LEP) and the leptin receptor gene (LEPR) as well as leptin expression in pre- and postbariatric surgery patients using a comparative cross-sectional design. Results: Our results revealed significantly higher LEP promoter methylation patterns in prebariatric surgery patients compared to postoperatively. DNA methylation of the LEPR promoter was significantly higher in the postoperative group. Moreover, we found significantly higher leptin serum levels in patients before the bariatric surgery than afterwards. Discussion: These findings strengthen the suggestion that there is an association between LEP expression and LEP methylation in obesity. We suggest that the epigenetic profile of LEP might be influenced by leptin serum levels in the form of a regulating feedback mechanism.

Effect of non-surgical periodontal therapy on salivary and serum leptin levels in patients with generalized stage II grade B periodontitis

Effect of non-surgical periodontal therapy on salivary and serum leptin levels in patients with generalized stage II grade B periodontitis

Modulation of the serum leptin by thyroid hormones: Observations in newly diagnosed thyrotoxic patients

Background: Leptin and thyroid hormones both are involved in regulation of energy metabolism. Many studies were conducted for studying the relationship and the interaction between the thyrostat and the lipostat which till present is incompletely understood. The aim of this work was to study serum leptin levels in patients suffering from thyrotoxicosis who are newly diagnosed treatment naive patients, thus the association between leptin and thyroid hormones can be purified as much as possible. Methods: a case control study conducted at Port-Said General hospital endocrine out-patient clinic. The study included 15 patients with thyrotoxicosis and 30 control euthyroid subjects (15 lean, 15 obese). All of the included patients are analyzed for thyroid profile and serum leptin. Results: The results revealed a statistically significant difference regarding serum leptin between the Thyrotoxic group and control obese. No correlation was found between serum leptin and either BMI, TSH, Free T3 or Free T4 in each of the studied group, but a significant negative correlation was found between leptin and either free T3 and free T4 in the combined groups. Conclusion: Serum leptin level is lower in treatment naive thyrotoxic patients when compared to euthyroid control. The serum leptin showed no correlation with either BMI or TSH, also no correlation was found between serum leptin and free T3 or free T4 in each of the studied group suggesting presence of other factors that indirectly affect and interconnect these two major endocrinal systems involving energy metabolism.

Vitamin D supplementation does not affect serum leptin and adiponectin levels in adults: A systematic review and meta-analysis of randomised controlled trials

Background &amp; aims: It is proposed that vitamin D supplementation might influence serum adipokines level; however, the recent meta-analyses have led to inconsistent results while they had methodological limitations. Therefore, this study aimed to examine the effects of vitamin D supplementation on serum adipokines through a systematic review and a meta-analysis of randomized placebo-controlled trials (RCTs) using a more comprehensive search strategy.&#x0D; Methods: PubMed, Google Scholar, and Scopus were searched to identify related articles published up to November 2017. Mean±standard deviation (SD) of changes in serum adiponectin and leptin were extracted, and the effect sizes were pooled using a random-effects model. Studies with Controlled clinical trials design were eligible. Two reviewers extracted mean values and SDs of the baseline, final and net change values of leptin and adiponectin in the intervention and control groups.&#x0D; Results: The pooled results indicated that vitamin D supplementation affects neither circulating leptin (Hedges’ g = 0.042, 95% CI: -0.294 to 0.378, p = 0. 0.807, n=15) nor adiponectin (Hedges’ g = -0.034, 95% CI: -0.243 to 0.174, p = 0.748, n=18) levels. Subgroup analysis showed that vitamin D supplementation might significantly decrease serum leptin level in patients with end stage renal disease (Hedges’ g = -0.634, 95 % CI: -1.221 to -0.047, p = 0.034).&#x0D; Conclusions: Although the current evidence does not support the significant effect of vitamin D supplementation on adiponectin and leptin levels, further research is required to reach more definitive conclusions.

Relationship of dietary and serum zinc and leptin levels with protein energy wasting in haemodialysis patients.

This study was carried out to evaluate the relationship between dietary and serum zinc and leptin levels with protein-energy wasting (PEW) in haemodialysis patients. The study was conducted on 80 volunteer patients aged 19-65years who received haemodialysis treatment three times a week for at least 1year. Anthropometric measurements and body composition analyses were performed. Blood samples were collected for serum zinc and leptin and other biochemical parameters. Food consumption of the patients was recorded for 3 days. Malnutrition-inflammation score (MIS) was calculated for all patients. PEW was assessed according to the criteria recommended by the International Society of Renal Nutrition and Metabolism (ISRNM). According to the ISRNM criteria, 38.1% of male patients and 36.8% of female patients were diagnosed with PEW. The median serum leptin levels of patients with PEW [9.0 (16.9) ng/mL] were significantly lower than those without PEW [20.7 (38.5) ng/mL] (p < 0.05). Dietary zinc intake in patients with PEW was significantly lower than that in patients without PEW (p < 0.05). However, there was no significant difference in serum zinc levels between the patients with and without PEW. In the multivariate analyses, dietary and serum zinc and leptin was associated with PEW. After controlling for several confounding factors these associations disappeared. Dietary zinc intake and serum leptin levels were inversely correlated with MİS. There was no relationship between serum leptin and dietary and serum zinc in these patients. Dietary zinc intake and serum zinc and leptin concentration were not associated with PEW. Low serum leptin levels might be the outcome rather than the cause of PEW in haemodialysis patients.

Increased Serum Leptin Level Predicts Bone Mineral Density in Hemodialysis Patients.

Background Leptin acts through the adipose-bone axis to regulate bone mineral density (BMD). This study evaluated the relationship between BMD and serum leptin levels in patients on hemodialysis. Methods In this cross-sectional study including 98 hemodialysis patients, BMD was measured using dual energy X-ray absorptiometry of the lumbar vertebrae (L2–L4), and serum leptin levels were determined using an enzyme immunoassay. Results There were 25 (25.5%), 13 (13.3%), and 60 (61.2%) patients with osteopenia, osteoporosis, and normal BMD, respectively. Advanced age (P=0.017); decreased body mass index (BMI, P < 0.001); body height (P < 0.001); prehemodialysis body weight (BW, P < 0.001); post-hemodialysis BW (P < 0.001); waist circumference (P < 0.001); and triglyceride (P=0.015), albumin (P=0.004), and leptin levels (P=0.017) were associated with lower lumbar T scores, whereas increased urea reduction rate (URR, P=0.004) and fractional clearance index for urea (Kt/V, P=0.004) were associated with lower lumbar T scores. The multivariable forward stepwise linear regression analysis with adjustment for sex; age; body height; prehemodialysis BW; BMI; waist circumference; logarithmically transformed triglycerides (log-triglycerides), albumin, creatinine, and leptin (log-leptin) levels; URR; and Kt/V indicated that high serum level of log-leptin (R2 change = 0.184; P < 0.001), increased prehemodialysis BW (R2 change = 0.325; P=0.008), male sex (R2 change = 0.048; P=0.001), young age (R2 change = 0.044; P=0.012), and increased serum albumin level (R2 change = 0.017; P=0.044) were significantly and independently associated with lumbar BMD. Conclusions Advanced age and female sex were associated with poor BMD, whereas increased BW, serum albumin, and leptin levels were positively associated with BMD in patients on hemodialysis.

Circulating Leptin Levels as a Potential Biomarker in Inflammatory Bowel Diseases: A Systematic Review and Meta-Analysis.

The differential diagnosis of inflammatory bowel diseases (IBDs) between Crohn's disease (CD) and ulcerative colitis (UC) is important for designing an effective therapeutic regimen. However, without any adequate gold standard method for differential diagnosis currently, therapeutic design remains a major challenge in clinical practice. In this context, recent studies have showed that circulating leptin stands out as a potential biomarker for the categorization of IBDs. Thus, we aimed to summarize the current understanding of the prognostic and diagnostic value of serum leptin in patients with IBDs. A systematic search was performed in PubMed/MEDLINE, Scopus, Cochrane Library, and Web of Science databases. Articles that aimed to study the relationship between circulating levels of leptin and IBDs were included. Finally, the meta-analysis was performed with the mean serum leptin levels in patients with IBDs and healthy controls using RevMan 5.3 software, with I2 > 50% as a criterion for substantial heterogeneity. Nineteen studies were included. Serum leptin levels among patients with IBDs and healthy controls did not show a significant difference (95% CI, -2.15 to 0.57; I2, 86%, P ≤ 0.00001). Similarly, there was no association of leptin levels with the activity of IBDs (95% CI, -0.24 to 0.06; I2, 50%; P = 0.13). However, serum leptin levels were significantly higher in patients with CD than those in patients with UC (95% CI, -2.09 to -0.37; I2, 7%; P ≤ 0.36). This review suggested that serum leptin levels might be a promising biomarker to help in the differentiation between CD and UC.