Serum leptin and its relationship with metabolic variables in Arabs with type 2 diabetes mellitus.
OBJECTIVE
Most studies on serum leptin in type 2 diabetes mellitus have focused on white populations. We studied serum leptin concentrations and parameters related to glycemic control and the association between leptin levels and anthropometric and metabolic factors in Arab patients with type 2 diabetes and in Arab control subjects.


METHODS
Ninety-two patients (65 females and 27 males) with type 2 diabetes and 69 matched normal control subjects (48 females and 21 males) were included. Anthropometric measures (including body mass index [BMI] and waist:hip ratio) were assessed in all subjects. After an overnight fast, blood was collected for serum leptin assay. Other metabolic parameters including glucose, insulin, C-peptide, intact proinsulin, insulin resistance index (HOMA-IR), insulin-like growth factor 1 (IGF-1), lipids and hemoglobin A1c (HbA1c) were determined.


RESULTS
Fasting serum leptin levels, IGF-1 and high-density lipoprotein (HDL) cholesterol were similar in patients with type 2 diabetes and control subjects. When obese subjects (BMI > or =30 kg/m2) were analyzed separately, serum levels of leptin were significantly lower in patients compared to controls. In contrast, patients had higher fasting glucose, insulin, C-peptide, intact proinsulin, insulin resistance, total cholesterol, triglycerides, HbA1c, and a larger waist circumference and waist-to-hip ratio than controls. Serum leptin correlated positively with BMI, negatively with waist-to-hip ratio, and demonstrated no relationship to other parameters.


CONCLUSIONS
Patients with type 2 diabetes in an Arab ethnic population showed evidence of an unfavorable metabolic profile despite having leptin levels similar to controls. Obesity influences serum leptin levels more significantly in type 2 diabetes, in which leptin levels tends to be low.
Al-Shoumer
Kamal A
KA
Division of Endocrinology and Metabolic Medicine, Mubarak Al-Kabeer Hospital, Kuwait University, Jabriya, Kuwait. kshoumer@gmail.com
Al-Asousi
Adnan A
AA
Doi
Suhail A
SA
Vasanthy
Bagavathy A
BA
D000328:Adult; D018912:Arabs / Q000208:ethnology; D001786:Blood Glucose / Q000378:metabolism; D015992:Body Mass Index; D002096:C-Peptide / Q000378:metabolism; D016022:Case-Control Studies; D002784:Cholesterol / Q000097:blood; D008076:Cholesterol, HDL / Q000097:blood; D003924:Diabetes Mellitus, Type 2 / Q000208:ethnology / Q000378:metabolism*; D005260:Female; D006442:Glycated Hemoglobin / Q000378:metabolism; D006801:Humans; D007328:Insulin / Q000378:metabolism; D007333:Insulin Resistance; D007334:Insulin-Like Growth Factor I / Q000378:metabolism*; D020738:Leptin / Q000097:blood*; D008297:Male; D009765:Obesity / Q000150:complications*; D011384:Proinsulin / Q000378:metabolism; D014280:Triglycerides / Q000097:blood; D049629:Waist-Hip Ratio
D001786:Blood Glucose; D002096:C-Peptide; D002784:Cholesterol; D008076:Cholesterol, HDL; D006442:Glycated Hemoglobin; D007328:Insulin; D007334:Insulin-Like Growth Factor I; D020738:Leptin; D011384:Proinsulin; D014280:Triglycerides
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