What hormonal tests, such as cortisol, should a man with sleep apnea and weight gain undergo?

From the Guidelines

A man with sleep apnea and weight gain should undergo several key hormonal tests, including morning cortisol, thyroid function tests (TSH, free T4, free T3), testosterone (total and free), insulin and glucose levels (fasting and HbA1c), and growth hormone/IGF-1. These tests are important because sleep apnea and weight gain can both cause and result from hormonal imbalances. Elevated cortisol from chronic stress or Cushing's syndrome can contribute to central obesity and sleep disturbances. Hypothyroidism often presents with weight gain and can worsen sleep apnea. Low testosterone is common in men with obesity and sleep apnea, creating a negative cycle as poor sleep further reduces testosterone production. Insulin resistance and prediabetes/diabetes frequently accompany weight gain and can be exacerbated by sleep apnea. Growth hormone deficiency may also be present, as sleep apnea disrupts the deep sleep phases when growth hormone is primarily released. These hormonal imbalances often interact with each other, so comprehensive testing is essential for developing an effective treatment plan that addresses both the sleep apnea and weight issues 1.

Some key points to consider in the management of sleep apnea and weight gain include:

• The importance of weight management in reducing sleep apnea severity, as highlighted by the American Thoracic Society guideline 1
• The high prevalence of obstructive sleep apnea in individuals with type 2 diabetes, and the potential benefits of sleep apnea treatment on quality of life and blood pressure control 1
• The need for comprehensive medical evaluation and assessment of comorbidities, including screening for sleep apnea in patients with symptoms suggestive of the condition 1
• The potential for hormonal imbalances, such as growth hormone deficiency, to contribute to sleep apnea and weight gain, and the importance of testing for these imbalances in developing an effective treatment plan 1

In terms of specific hormonal tests, the following may be considered:

• Morning cortisol to assess for Cushing's syndrome or other adrenal disorders
• Thyroid function tests (TSH, free T4, free T3) to assess for hypothyroidism
• Testosterone (total and free) to assess for low testosterone
• Insulin and glucose levels (fasting and HbA1c) to assess for insulin resistance and prediabetes/diabetes
• Growth hormone/IGF-1 to assess for growth hormone deficiency.

From the Research

Hormonal Tests for Weight Gain in Sleep Apnea

A man with sleep apnea experiencing weight gain may want to consider the following hormonal tests:

• Ghrelin: a hormone that regulates appetite and metabolism, which has been shown to decrease significantly with CPAP treatment in obese subjects with OSA 2
• Insulin: as changes in body weight directly correlate with changes in insulin and insulin resistance (IR) 2
• Other hormones such as leptin, adiponectin, and resistin may also be relevant, although their levels remained unchanged in the study 2
• Cortisol and prolactin levels may not be directly related to weight gain in sleep apnea, but could be considered as part of a broader hormonal panel

Relationship Between CPAP Treatment and Weight Gain

CPAP treatment has been shown to increase body mass index (BMI) in patients with OSA, especially in those with CPAP use of ≤5 h/night, without cardiovascular disease, and/or with dysglycemia at baseline 3

• Weight gain is a common issue in patients with OSA, with one study finding that 40% of patients gained weight significantly after 6 months of CPAP treatment 2
• Another study found that high adherence to CPAP treatment did not prevent the continuation of weight gain among severely obese OSAS patients 4

Weight Loss and Lifestyle Interventions

An interdisciplinary weight loss and lifestyle intervention has been shown to result in clinically meaningful and sustainable improvements in OSA severity and comorbidities, as well as health-related quality of life 5

• This approach may be considered as a central strategy to address the substantial impact of OSA on weight gain and overall health
• Patients with OSA may be susceptible to increasing obesity in the period preceding the diagnosis of OSA, highlighting the importance of early intervention and weight management strategies 6