Obstructive sleep apnoea syndrome impairs insulin sensitivity independently of anthropometric variables.

OBJECTIVES: Obstructive sleep apnoea syndrome (OSAS) is strongly associated with obesity and characterized by endocrine and metabolic changes including impairment of insulin sensitivity. The aim of this study was to further clarify the insulin dynamics and glucose metabolism in this condition. DESIGN, PATIENTS AND MEASUREMENTS: We studied 30 obese patients with OSAS [OSA, 21 males, 9 females; age, mean +/- SEM: 53.1 +/- 1.7 years; body mass index (BMI): 38.6 +/- 1.1 kg/m2; waist-to-hip ratio (WHR): 0.99 +/- 0.07; Apnoea/Hypopnoea Index (AHI): 40.5 +/- 5.8 events/h of sleep] by means of overnight polysomnography and oral glucose tolerance testing. Mathematical models were used to assess: (i) whole-body insulin sensitivity index (ISI composite); (ii) hepatic ISI; (iii) the first phase of insulin secretion (DeltaI30'-0'/DeltaG30'-0'). Results were compared with those in 27 weight-matched patients with simple obesity (OB, 12 males, 15 females; age: 48.1 +/- 2.8 years, BMI: 38.5 +/- 1.4 kg/m2, WHR: 0.94 +/- 0.09; AHI: 2.15 +/- 0.5 events/h of sleep) and with 20 normal subjects (NS, 15 females; 5 males, age: 40.4 +/- 2.9 years; BMI: 22.2 +/- 0.6 kg/m2). RESULTS: ISI composite value was significantly lower in OSAS (1.71 +/- 1.41) than in OB (3.08 +/- 0.27) and in NS (6.1 +/- 0.4) even after age-, BMI- and WHR-adjustment. Similarly, hepatic ISI was significantly different among the three groups (OB = 0.25 +/- 0.02, OSAS = 0.16 +/- 0.014 and NS = 0.55 +/- 0.04). Sex did not affect ISI indices. Insulin secretion estimates were not significantly different among the three groups. DISCUSSION: Obese patients with obstructive sleep apnoea syndrome are more insulin resistant than patients with simple obesity independently of the degree and distribution of adiposity. The worsening in insulin sensitivity in obstructive sleep apnoea syndrome patients could reflect the hypoxic state and would account for the increased vascular risk in this condition.

Puumala virus pulmonary syndrome in a Romanian immigrant.

Hantaviruses belong to the Bunyaviridae family, which is comprised of Bunyavirus, Phlebovirus, Nairovirus, and Hantavirus. Euroasiatic Hantaviruses belong to two distinct subfamilies: Murinae (comprising Hantaan, Dobrava, and Seoul viruses), which are responsible for hemorrhagic fever with renal syndrome (HFRS), and Arvicolinae (comprising Puumala virus), responsible for nephropathia epidemica (NE) and HFRS. On the contrary, the New World Hantavirus belongs to the Sigmodontinae subfamily and includes the North American viruses: Sin Nombre, Monongahela; New York, Bayou, Black Creek Canal, and the South American, which comprise the Andes, Oran, Lechiguanas, Laguna Negra, Juquitiba; both groups are responsible for the hantavirus pulmonary syndrome (HPS).