Relationship of leptin and insulin resistance in patients with obstructive sleep apnea syndrome

    XU Jianª²Ping, ZHANG Bingª²Fang, QIU Jianª²Hua, WU Changª²Gui

    1Department of Respiratory Diseases, 2Department of Otorhinolaª²ryngology, Xijing Hosptial, Fourth Military Medical University, Xi¬ðan 710033, China

    ¡¾Abstact¡¿ AIM: To explore the relationship between serum leptin level and insulin resistance in patients with obstructive sleep apnea syndrome (OSAS). METHODS: Polysomnography was performed in all the enrolled cases, which were divided into four groups by body mass index (BMI) and apnea hypopnea index (AHI): group A obese OSAS (BMI¡Ý27, AHI¡Ý5), group B nonª²obese OSAS (BMI<25, AHI¡Ý5), group C simple obese (BMI¡Ý27, AHI<5) and group D normal control (BMI<25, AHI<5). Fasting plasma glucose (FPG) levels were measured by glucoseoxidase, fasting insulin (FINS) and fasting leptin levels were measured by radioimmunoassay. RESULTS: ¢ÙThe serum insulin levels in groups A, B and C [(15.6¡À3.6), (11.7¡À2.3), (11.3¡À2.5) mU/L] were higher than that of group D [(9.1¡À1.8) mU/L, P<0 01] and the insulin level in group A was higher than those in groups B and C(P<0.01). ¢ÚThe serum leptin levels in groups A, B and C [(6.6¡À1.4), (4.7¡À0.9), (4.2¡À0.7) ¦Ìg/L] were higher than that in group D [(3.4¡À1.0) ¦Ìg/L, P<0.05-0.01] and the leptin level in group A was higher than those in groups B and C(P<0.01). ¢ÛThe HOMAª²IR in groups A, B and C(4.0¡À1.4, 3.0¡À0.8, 2.8¡À0.6)was higher than that in group D (2.1¡À0.6) (P<0.05-0.01) and HOMAª²IR in group A was higher than those in groups B and C(P<0.01). ¢ÜThe leptin levels in the OSAS patients were obviously correlated with BMI, insulin and HOMAª²IR. CONCLUSION: Fasting plasma leptin level is closely related with the insulin resistance in patients with OSAS. ......