Association between inadequate sleep and insulin resistance in obese children.

OBJECTIVE: To analyze the relationships between sleep duration, obstructive sleep apnea syndrome (OSAS), and markers of insulin resistance in obese children. STUDY DESIGN: Forty obese children were evaluated for sleep-related complaints. Each child underwent a polysomnogram, an oral glucose tolerance test (OGTT), and fasting lipid panel tests. Indices of insulin resistance (HOMA-IR and WBISI) and insulin secretion (IGI) were calculated based on the results of the OGTT. Markers of insulin resistance were compared among groups categorized according to polysomnogram results. RESULTS: Subjects with shorter sleep duration had higher fasting insulin, peak insulin, and HOMA-IR levels and lower WBISI levels, findings suggestive of insulin resistance. In contrast, differences in body mass index z scores were not observed. Subjects with OSAS (32 of 40 children) had higher triglyceride levels and HOMA-IR values than those without OSAS, but did not differ in sleep duration. Multiple linear regression analysis revealed that HOMA-IR was significantly correlated with age, sleep duration, and percentage of rapid-eye-movement sleep. CONCLUSIONS: Insulin resistance in obese children is associated with short sleep duration and OSAS.

Surgical lung biopsy in patients with hematological malignancy or hematopoietic stem cell transplantation and unexplained pulmonary infiltrates: improved outcome with specific diagnosis.

Using a retrospective review of medical records, we sought the findings of surgical lung biopsy (SLB) in patients with hematological malignancy or hematopoietic stem cell transplantation (HSCT) and unexplained pulmonary infiltrates and to determine the impact of this procedure on management and outcome of these patients. Sixty-two patients who underwent SLB were evaluated; 31 patients had underlying hematological malignancy and 31 patients were HSCT recipients; 58% of whom underwent allogeneic HSCT. Thirty-three patients (53%) had focal infiltrates on chest CT scan while 29 (47%) had diffuse infiltrates. Thirteen patients were mechanically ventilated prior to SLB, and 27 (43%) were neutropenic. There were 66 diagnoses in the 62 patients, 44 (67%) were specific and 22 (33%) were nonspecific. The most common specific diagnoses were infection (29%), malignancy (27%), and inflammatory conditions (11%). Aspergillosis was the most common diagnosis of all biopsies (21%). SLB led to a change in therapy in 40% of patients and was associated with complications in 7 patients (11%). Specific diagnosis was more likely to lead to a change in therapy (48% vs. 27%, P = 0.06) and was associated with a lower mortality when compared to a nonspecific finding (30% vs. 59%, P = 0.02). Nonspecific diagnosis, on the other hand, was seen more in patients on mechanical ventilation prior to SLB compared to those off mechanical ventilation (69% vs. 27%, P = 0.02). SLB provides a specific diagnosis in the majority of patients with hematologic malignancy or HSCT recipients and unexplained pulmonary infiltrates. Specific diagnosis is more likely to lead to a change in therapy and is associated with a better outcome.