Sleep Apnea in Obese People Can Lead to Sensory Neuropathy

Abstract

Obesity is frequently acquainting as an abnormal accumulation of body fat to the degree that may cause serious health consequences. ( Yanovski et al., 2014). One of the most common complication of obesity is obstructive sleep apnea(OSA). Obstructive Sleep Apnea is a widespread complaint that is closely associated with global obesity epidemics, and it is described as frequent complete or partial flop of the upper airway during sleep leading to gaseous exchange impairment and disturbance of sleep. It is the commonest category of sleep disordered breathing (SDB) in the world as reported in different epidemiological studies. (McNicholas et al., 2007).

Central sleep apnea : is described  as decreased respiratory effort leading to decrease or absence of ventilation .While in mixed apnea it is categorized by starting centrally and ending with obstructive events.In obstructive sleep apnea: the effort of  respiration is preserved but ventilation decrement  or absence due to partial or total obstruction in the upper airway; apnea is well-defined as the total airflow cessation lasting 10 sec. or more , There are three types of apneas :obstructive, central and mixed . A hypopnea: is defined as a reduction in airflow (30-50%) that is followed by an arousal from sleep or a decrease in oxyhaemoglobin saturation (3-4%)( The Report of an American Academy of Sleep Medicine Task Force, 1999 and Kushida et al.,2005).

The severity of sleep apnea is evaluated with apnea-hypopnea index (AHI), which is the number of apneas and hypopneas per hour of sleep.

According to the American Academy of sleep Medicine recommendations , OSA is defined with AHI>5., and it is classified as mild OSA with AHI of 5 to 15;moderate OSA with AHI of 16 to 30;and severe OSA with AHI > 30.(The Report of an American Academy of Sleep Medicine Task Force, 1999).

The Apnea–Hypopnea Index or Apnoea–Hypopnoea Index (AHI) is an index used to determine sleep apnea severity. It is characterized by the number of apnea and hypopnea events per hour of sleep. The apneas (pauses in breathing) must last for at least 10 seconds and associated with a decrease in blood oxygenation. Combining AHI and oxygen desaturation measurement gives a complete sleep apnea severity score that assesses the number of sleep disruptions and degree of oxygen desaturation.               (Ruehland et al.,2009 ).

The AHI is calculated by dividing the number of apnea events by the number of hours of sleep. AHI values are categorized as

Normal: 0-4;Mild Sleep Apnea: 5-14;Moderate Sleep Apnea: 15-29; Severe Sleep Apnea: 30 or more.(Ruehland et al., 2009 ).