What is a constructive way to handle morbid obesity as a strong cofactor for severe Obstructive Sleep Apnea (OSA)?

From the Guidelines

To effectively manage morbid obesity as a significant cofactor for severe obstructive sleep apnea (OSA), a comprehensive lifestyle intervention program that includes a reduced-calorie diet, exercise/increased physical activity, and behavioral counseling is strongly recommended. This approach is based on the latest guidelines from the American Thoracic Society, as outlined in the 2018 clinical practice guideline 1. The key components of this program include:

• A reduced-calorie diet, with a daily caloric intake of 1200-1500 calories for women and 1500-1800 calories for men
• Regular physical activity, aiming for 150-300 minutes of moderate exercise per week, starting gradually
• Behavioral counseling to address eating habits and lifestyle modifications For patients with a BMI ≥35 with comorbidities or BMI ≥40, bariatric surgery options such as gastric bypass or sleeve gastrectomy may be considered, as they can provide substantial weight reduction and often dramatic OSA improvement 1. Additionally, medications such as phentermine-topiramate (Qsymia), semaglutide (Wegovy), tirzepatide (Zepbound), orlistat (Xenical), and naltrexone-bupropion (Contrave) may be helpful in achieving weight loss. It is essential to ensure proper OSA treatment with CPAP therapy while pursuing weight loss, as untreated OSA can hinder weight loss efforts due to metabolic effects and fatigue limiting physical activity 1. This comprehensive approach addresses both conditions simultaneously, with weight loss of 10-15% potentially reducing OSA severity by 50% or more.

From the FDA Drug Label

Phentermine Hydrochloride, USP 15 mg and 30 mg is indicated as a short-term (a few weeks) adjunct in a regimen of weight reduction based on exercise, behavioral modification and caloric restriction in the management of exogenous obesity for patients with an initial body mass index greater than or equal to 30 kg/m 2, or greater than or equal to 27 kg/m 2 in the presence of other risk factors (e.g., controlled hypertension, diabetes, hyperlipidemia).

The management of morbid obesity as a strong cofactor for severe OSA may involve the use of phentermine as an adjunct to a weight reduction regimen that includes exercise, behavioral modification, and caloric restriction.

• Key considerations:
  • Phentermine is indicated for patients with a BMI ≥ 30 kg/m² or ≥ 27 kg/m² with other risk factors.
  • The recommended dose is 15-30 mg daily, individualized to obtain an adequate response with the lowest effective dose.
  • Phentermine should be used for a short-term period (a few weeks) due to the potential for tolerance and abuse.
  • Patients should be monitored for potential side effects, including primary pulmonary hypertension and valvular heart disease 2.
  • It is essential to approach the treatment of morbid obesity with caution, considering the potential risks and benefits of phentermine therapy 2.
  • The dosage should be adjusted according to the patient's response and renal function, if necessary 2.

From the Research

Constructive Ways to Handle Morbid Obesity as a Strong Cofactor for Severe OSA

• Weight reduction is a crucial aspect in managing OSA, as it can lead to a significant improvement in symptoms 3, 4
• A weight loss of around 15% of baseline body weight can substantially increase the pharyngeal cross-sectional area and improve the severity of OSA in morbidly obese subjects 4
• Sustainable weight loss can be difficult to achieve without bariatric surgery, but recent advances in incretin-based pharmacotherapies represent a promising avenue for long-term weight loss and treatment of OSA 5
• Continuous positive airway pressure (CPAP) therapy remains the most widely prescribed treatment for OSA, but poor tolerance is a common barrier to effective treatment 5, 6
• Treatment of OSA with CPAP can have a positive effect on metabolic derangements, and new anti-diabetic drugs may be useful in the treatment of obese OSA patients 6

Importance of Weight Loss in Managing OSA

• Weight loss can lead to a reduction in waist circumference, sagittal abdominal diameter, and neck circumference, all of which are associated with improved OSA symptoms 4
• Weight loss can also lead to an increase in the size of the upper airway passage, making it easier to breathe during sleep 4
• Morbidly obese men with OSA have a reduced pharyngeal cross-sectional area, which can be improved with weight loss 4

Perioperative Care for Morbidly Obese Patients with OSA

• Obesity and OSA are associated with increased perioperative risks and challenges for the anesthesiologist 7
• Preoperative selection of obese and OSA patients for ambulatory surgeries, intraoperative methods to reduce perioperative risk, and appropriate postoperative care are crucial in managing these patients 7