Abdul Hadi Mohamed

Association Between Severity of Obstructive Sleep Apnea and Number and Sites of Upper Airway Operations With Surgery Complications

Importance In patients with obstructive sleep apnea (OSA), operative risks depend on the severity of the underlying OSA and the invasiveness of the surgical procedure. Objective To investigate the nature of the associations between the severity of OSA and the number and anatomical sites of upper airway operations with operative complications. Design, Setting, and Participants This retrospective study included adult patients diagnosed with OSA (apnea-hypopnea index [AHI], >5) who underwent upper airway surgery at a single tertiary referral hospital between October 1, 2008, and October 1, 2015. Interventions All patients underwent single or combination surgery on the nose, palatopharyngeal (tonsils, adenoids, and soft palate), and tongue base as a treatment of OSA. Main Outcomes and Measures Pulmonary, surgical, and cardiovascular complications within the first 30 postoperative days were analyzed according to OSA severity and types of upper airway surgery. Logistic regression was used to assess the multivariable association of OSA, age, sex, body mass index, medical comorbidities, and types of upper airway surgery with short-term operative complications. Results The study included 95 patients (87 males [91.6%]; 83 were Malay [87.4%]; mean [SD] age, 37.7 [1.6] years) with complete data and follow-up who underwent upper airway surgery to treat OSA. Patients with more severe OSA had greater body mass index (Cohen d, 0.27; 95% CI, −0.28 to 0.82), longer surgical time (Cohen d, 1.57; 95% CI, 0.95-2.15), and older age (Cohen d, 3.06; 95% CI, 2.29-3.77). At least 1 operative complication occurred in 48 of 95 patients (51%). In a multivariable model, the overall complication rate was increased with age and body mass index. Complication rates were not associated with AHI severity, type of procedure performed, and whether the surgery was single or combination surgery. Lowest oxygen desaturation (odds ratio, 1.03; 95% CI, 0.96-1.45; P = .04) and longest apnea duration (odds ratio, 1.03; 95% CI, 0.99-1.08; P = .02) were polysomnographic variables that predict the short-term operative complications. Conclusions and Relevance In patients with OSA undergoing upper airway surgery, the severity of OSA as assessed by AHI, and the sites and numbers of concurrent operations performed were not associated with the rate of short-term operative complications.

Organic Arsenical Exposure Stimulates Atherosclerosis Through Oxidative Stress Increase and Adhesion Molecule Expression

Approximately 100 million people are exposed to arsenic worldwide, majorly through drinking water and anthropogenic activities. Monosodium methylarsonate (MSMA) is a potent organoarsenical content of herbicides used in many Asian countries. Epidemiological studies have linked inorganic arsenic exposure with atherosclerosis, whereas organoarsenicals toxicological studies are scanty. Paraoxonase 1 (PON1) enzyme suppresses systemic Ox-LDL generation, thereby preventing atherosclerosis. We investigated effects of MSMA oral exposure on PON1, lipid peroxidation and atherosclerosis development. Five groups (n=11) of Sprague- Dawley rats received daily intubation of MSMA at 0 (control), 42.1, 63.2, 126.4 and 210.7 mg/kg BW respectively for 16 weeks. Serum samples were analysed for PON1 activities, Ox-LDL and MDA levels. Histomorphometric evaluation (H&E and VVG) and immunohistochemistry (VCAM-1 and ICAM-1) were done on aorta. High mortality rate led to discontinuation of 126.4 and 210.7 mg/kg BW treatment groups. Groups treated with 42.1 and 63.2 mg/kg B.W. MSMA had a significantly higher MDA (p=0.004,CI: 2.73-0.82) and Ox-LDL (p<0.0001,CI: 2425.07-955.45) levels but lower PON1:Ox-LDLratio (p<0.0001,CI: 0.49-1.07) compared to control. Microscopically, treatment groups showed early atherosclerotic intima thickening and positive VCAM-1 and ICAM-1 expressions. In conclusion, chronic MSMA exposure reduced PON1 ability to hydrolyse Ox-LDL and also induced inflammation by elevating oxidative stress that supports early atherosclerosis development.