Autonomic neuropathy increases the risk of obstructive sleep apnea in obese diabetics.

BACKGROUND: Nonobese diabetics with diabetic autonomic neuropathy (DAN) show an elevated prevalence of obstructive sleep apnea-hypopnea (OSAH). OBJECTIVE: It was the aim of this study to assess if the presence of DAN could further increase the risk of developing OSAH in obese diabetics. METHODS: Eighteen obese diabetic patients, 8 with DAN [age 57 +/- 5 years, body mass index (BMI) 35 +/- 4] and 10 without DAN (age 56 +/- 8 years, BMI 37 +/- 5), were recruited. Ten age-matched obese subjects were studied as controls (age 53 +/- 12 years, BMI 34 +/- 3). All subjects underwent a cardiorespiratory sleep study in the in-hospital sleep laboratory to obtain the apnea-hypopnea index (AHI) and oxygen desaturation indices. RESULTS: Diabetics with DAN (Ob-DAN+) had a higher AHI than diabetics without DAN (Ob-DAN-) and controls, amounting to 39.5 +/- 13 versus 15.8 +/- 12 (p < 0.01) and 19.3 +/- 21 (p < 0.05), respectively. A moderate-to-severe OSAH (AHI > or = 15) occurred in all Ob-DAN+ and only in 4 Ob-DAN- and 4 control patients. Moreover, the indices reflecting the impairment of oxygen saturation (SaO(2)) during sleep such as the mean lowest SaO(2) and sleep time with a SaO(2) <90% were more severely affected in Ob-DAN+ patients compared with the other groups and were associated with longer obstructive respiratory events. CONCLUSIONS: Apneas-hypopneas are more frequent and last longer in Ob-DAN+ than in other obese subjects, with or without diabetes.

Effects of CPAP on systemic hypertension in OSAH: a monocentric, observational, cohort study.

BACKGROUND: Obstructive sleep apnea-hypopnea (OSAH) is a risk factor for development of systemic arterial hypertension (SAH) and can worse the control of established SAH. We investigated the effects of long-term continuous positive airway pressure (CPAP) treatment in controlling and preventing SAH in a large cohort of subjects referred for sleep study for suspected OSAH. METHODS: In 495 subjects of whom 422 with OSAH and 73 without OSAH, the clinical history was obtained, arterial blood pressure was measured and the current anti-hypertensive drugs was recorded at diagnosis and/or at CPAP start. Subjects were interviewed after a follow-up period of (mean ± SD) 3.4 ± 2.2 yr (range 1-8 yr) and divided in patients with moderate-to-severe OSAH (n = 125) who referred to use CPAP regularly for at least 4 h every night (group 1), with moderate-to-severe OSAH (n = 70) who refused or abandoned the CPAP treatment after few weeks (group 2), with mild OSAH (n = 227) with no CPAP indication (group 3) and simple snorers or normals (n = 73) (group 4). For each group clinical status, BMI, and changes in SAH therapy and occurrence of SAH were assessed at the follow-up. RESULTS: At the follow-up, a higher risk of increasing treatment for SAH was found for group 2 and group 3 versus group 1 (OR = 5, 95%CI 1-20, p < 0.01 and OR = 3, 95%CI 1-10, p < 0.05), respectively. The occurrence of SAH was lower (p < 0.001) in the group 1 (1.9%), vs group 2 (35.9%), 3 (21.1%) and 4 (18.6%). CONCLUSIONS: In moderate-to-severe OSAH patients, long-term CPAP treatment significantly reduces the development of SAH and, in those with SAH at baseline, the need of anti-hypertensive drugs.

[Obstructive sleep apnea syndrome and cardiovascular diseases]. / Sindrome dell'apnea ostruttiva notturna e malattie cardiovascolari.

Obstructive sleep apnea (OSA) syndrome is one of the most common respiratory disorders in humans. There is emerging evidence linking OSA to vascular disease, particularly hypertension. The underlying pathophysiological mechanisms that link OSA to cardiovascular diseases such as hypertension, congestive heart failure and atrial fibrillation are not entirely understood, although they certainly include mechanical events, increased sympathetic activity and oxidative stress. This review will examine the evidence and mechanisms linking OSA syndrome to cardiovascular disease.

Sleep apnea syndrome in endocrine diseases.

It is increasingly recognized that sleep-disordered breathing (SDB) - from snoring to apnea-hypopnea syndrome (SAHS) - can affect patients with various endocrine diseases (ED). Different mechanisms are implied in SDB, promoting either central or, more frequently, obstructive apnea in different ED. In the past, acromegaly and hypothyroidism were first associated with both central and obstructive SAHS. Today, great attention is placed on the complex cause-effect relationship between diabetes mellitus and obstructive SAHS (and vice versa). Symptoms and signs of SAHS may complicate the clinical course of these diseases and should be promptly suspected to detect and possibly treat the accompanying SDB.