Effect of Weight Loss on Upper Airway Anatomy and the Apnea–Hypopnea Index. The Importance of Tongue Fat

The Case of Sleep Apnoea and Cardiovascular Events

“…No sleep apnoea cohort study has specifically measured or adjusted for visceral and ectopic fat, adjusting instead by BMI and, very occasionally, waist circumference 17 . This limitation is extremely important when interpreting OSA cohort data since MRI and CT-measured intra-abominal fat 21 and ectopic fat in the tongue 22,23 are also the major drivers of OSA (AHI). Furthermore, tongue fat is strongly associated with visceral abdominal fat 22,24 and with increased risk of metabolic syndrome 24 .…”

“…Abdominal fat increases the risk and severity of OSA by increasing intra-abdominal pressure 25 and decreasing lung volume 26 and longitudinal traction on the upper airway 27 ; genioglossus fat does this by increasing tongue volume 22,23 . Thus, failure to adjust for visceral and ectopic fat in sleep apnoea cohort studies may have caused the cardiovascular and metabolic risk Failure to measure and adjust for visceral and ectopic fat may have led to significant residual confounding in cohort studies causing the association between obstructive sleep apnoea (OSA) and risk of cardiovascular (CV) disease and events to be overestimated.…”

“…Abdominal visceral fat and intramuscular ectopic fat deposits are pro-inflammatory, diabetogenic and atherogenic (A) 18 . Intramuscular fat deposits in the tongue cause the tongue to enlarge, encroach on the upper airway lumen and increase the risk of OSA (B) 22,23 attributed to OSA to be overestimated including in studies of incident diabetes 28 , hypertension 9 and metabolic syndrome 29 . Visceral fat is the main source of circulating biomarkers of inflammation.…”

Cardiovascular effects of non-invasive ventilation in the treatment of breathing-related sleep disorders in bariatric patients

“…Тяжесть СОАС прямо коррелирует с ИМТ -увеличение/уменьшение ИМТ на 1% повышает/снижает ИАГ на 3% [3]. Наиболее важным предиктором тяжести СОАС при снижении массы тела является уменьшение толщины языка [4].…”

Contemporary Concise Review 2019: Sleep and ventilation

“…We write this review to summarize a number of important topics with recent advances put into the context of the existing literature. While we recognize major progress in many different areas of sleep and ventilation, ranging from anatomic and non‐anatomic pathophysiological mechanisms of obstructive sleep apnoea (OSA), nocturnal symptoms and hypoxaemia in pulmonary disease and positive airway pressure (PAP), we have focused on those felt to be most important and likely to affect clinical practice …”