Pathogenesis of Obstructive Sleep Apnea Syndrome: A Histopathological Study

Abstract

Snoring is the most common sign of obstructive sleep apnea and must be looked on as a prime indicator of this disease entity. Profound hypersomnolence, cardiopulmonary sequelae, intellectual deterioration, impotence, personality changes and morning headaches are the additional . commonly associated symptoms. istinct histopathological changes have been detected in palate, uvula, posterior and lateral pharyngeal walls in patients with OSAS in the form of degeneration of the myelinated nerves, disruption of striated muscle bundles and mucous gland hypertrophy accompanied by extensive edema of lamina propria with vasodilatation. The objective of this study was to investigate the histopathological alteration and substance P distribution and effect in palatal and pharyngeal walls in patients with OSAS in an attempt to elucidate the pathogenesis of airway narrowing. The study included 40 patients who were divided into two equal groups (Snorers group and OSAS group). The results were classified into three main groups, clinica histopathological and immunohistochemical results. The results of the present work give an idea that substance P seems to play a role in etiopathology of OSAS, as the increase in substance P at sensory nerve terminals indicates an afferent nerve lesion contributing to the collapse of upper airway during sleep in OSAS patients. Also, substance P has an important role in the development of OSAS through different mechanism, increased oedema, congestion and muscle atrophy which will increase the upper airway collapsibility and decrease the intrapharyngeal lumen leading to upper airway narrowing.