4.1 Introduction

In the general population, it is estimated that 3.3 to 7.5% of men and 1.2 to 3.2% of women meet the diagnostic criteria for obstructive sleep apnea (OSA) syndrome as described previously (see Chapter 2). Yet, the number of patients who are asymptomatic but have an apnea–hypopnea index (AHI) greater than or equal to 5 is significantly higher: 17 to 27% in men and 5 to 28% in women. The estimated prevalence of an AHI greater than or equal to 15, ranges from 7 to 14% in men and 1.2 to 7% in women. It should be noted that comparison of the results of these epidemiology studies is limited by methodological differences, including variation in used criteria, sleep registration techniques, and study methods (e.g., sampling schedules).

On the basis of these prevalence estimates, roughly 1 of every 5 adults has at least an AHI greater than or equal to 5 and 1 of every 15 adults at least an AHI greater than or equal to 15. It is estimated that nearly 80% of men and 93% of women with moderate to severe OSA remain undiagnosed. ^{1 , 2 , 3 , 4 , 5 , 6 , 7 , 8 , 9 , 10 , 11}

At present, the therapeutic armamentarium for obstructive sleep apnea (OSA) comprises several treatment options. To provide effective treatment for OSA, careful consideration of the individual patient, available medical and surgical therapies, and inherent risks and complications of those interventions must be taken into account. While this book focuses on surgical treatment of OSA, an overview of conservative treatment measures is crucial. Many of these treatment modalities can be applied as single therapy or as combination therapy, which is gaining momentum.

Physicians and surgeons treating patients with OSA should be up-to-date with the modern therapeutic armamentarium for OSA. The approach to treating OSA is steadily moving from a continuous positive airway pressure (CPAP) centered one-size-fits-all approach to individualized treatment of upper airway obstruction during sleep.

Treatment of OSA is approached in a stepwise manner and begins with lifestyle alterations, indicated for all patients with a modifiable risk factor, such as weight reduction and avoidance of alcohol and sedatives. In case of supine-position dependency, avoidance of the supine sleeping position is recommended. Conservative treatment options include CPAP, oral appliances, and active positional therapy. All treatment modalities have their own specific indications, contraindications, and side effects. So far, no drugs have been identified to help against obstructive sleep apnea syndrome (OSAS), but pharmaceutical companies are working hard to develop them. ¹²

4.2 Lifestyle Intervention

Lifestyle interventions include weight reduction; physical activity and exercise to increase genioglossal muscle tone; and avoidance of alcohol, smoking, and sedatives.

Body weight is pivotal in OSA. Not everyone with OSA is obese, but most patients with morbid obesity have OSA. Even modest weight loss can be effective in reducing OSA severity, but there is a poor correlation between the amount of weight loss and the clinical response.

The exact pathophysiology of OSA in obese patients remains poorly understood; but it is thought that, in these patients, local fatty tissue deposition in the neck results in reduction of the lumen of the upper airway thereby reducing airflow and inducing airway collapse. ^{13 , 14} Most OSA patients are overweight and weight loss, even modest, can be effective in reducing OSA severity, with a clear relation between BMI and AHI. ^{15 , 16 , 17} Unfortunately, losing weight is particularly taxing in patients with OSA. Daytime hypersomnolence, an important symptom of OSA, reduces the motivation for physical activity and dieting. Secondly, OSA is thought to induce weight gain. Sleep deprivation and intermittent hypoxia cause impaired glucose metabolism, hyperphagia, and imbalances of leptin, ghrelin, and orexin levels. ^{18 , 19} Therefore, on the whole, conservative treatment fails more often in obese patients with OSA; in obese patients bariatric surgery (BS) can be considered. BS is not only the most effective treatment modality in obese patients to lose weight, producing durable weight loss, it is also known to have a positive effect on comorbidities. BS is therefore becoming increasingly popular. ²⁰

The likelihood of OSA increases with increasing body weight. It cannot be stressed enough that this works in both directions: OSA leads to weight gain as well. The reason for this is probably twofold: (1) patients with OSA tend to be relatively less active and might gradually lose their motivation for physical exercise, which will contribute to weight gain; (2) OSA can influence the production of leptin and ghrelin—hormones responsible for hunger and satiety. Lack of oxygen affects the insulin balance as well. Sugars are not burned effectively, but might be converted to fat.

Body shape and fat distribution might differ considerably from person to person. In terms of OSA risk, the neck circumference might be a better metric than body mass index (BMI). It is not completely clear as to how far it matters if the neck circumference is big because of fat or because of muscle mass.

It is important, however, to realize that while we all should advise our patients with OSA and increased body weight to try to lose weight, but for the vast majority of patients this is easier said than done. In the majority of patients it takes many years before the actual diagnosis is established. Patients often have complaints for an average of 5 to 8 years and in the meantime have been misdiagnosed as having a burnout or depression. When the diagnosis is finally established and the caregiver recommends patients to lose weight then their first reaction is often: “Do you really think I have not tried that?” In contrast, patients would appreciate if the doctor understands their frustrating situation and explains to them that weight loss in general is difficult, and with OSA it is even more difficult, but not impossible. This mutual understanding is essential for a good patient-doctor relation. Only a few percent of patients with OSA who are advised to lose weight actually manage to do so and subsequently are able to maintain this more healthy body weight.

4.3 Positional Therapy

The majority of patients with mild to moderate OSA have more apneic events in the supine position, as compared with nonsupine positions. ^{39 , 40 , 41 , 42 , 43 , 44} Positional OSA (POSA) was originally defined as an AHI that is at least twice as high in supine position as compared with nonsupine positions. ⁴¹ In approximately 56 to 75% of patients with OSA, the frequency and duration of apneas are influenced by body position. This is particularly true for patients with mild or moderate OSA.

Patients can be treated by simply avoiding the worst sleeping position, most often the supine position. ^{39 , 40 , 41 , 42 , 43 , 44 , 45 , 46 , 47 , 48 , 49 , 50 , 51}

Until recently, positional therapy (PT) consisted of suturing tennis balls, squash balls, (inflatable) bulky masses, or other such devices in the back side of a pajama or t-shirt in order to prevent patients from adopting the supine sleeping position. ³⁹

Promising results have recently been reported for active PT with a small device attached to either the neck or chest, which prevents the patient from adopting the supine position through a subtle vibrating stimulus ^{45 , 46 , 47 , 48 , 49 , 50 , 51} (▶Fig. 4.1a, b; ▶Fig. 4.2).

There is strong evidence that active PT is effective in reducing the AHI. ^{45 , 46 , 47 , 48 , 49 , 50 , 51} Furthermore, it is simple, relatively inexpensive, well tolerated, and reversible. Not only is PT successful, but it is also effective because of its high compliance. ^{47 , 49}

Further long-term high-quality studies are needed to confirm the promising role of PT as a single or as a combination treatment modality for many OSA patients.