Obstructive sleep apnea (OSA) is a common disorder in older people. Population-based studies have shown that the prevalence of OSA increases with age.
1. General Considerations
Obstructive sleep apnea (OSA) is characterized by a partial or complete obstruction of the upper airways for at least 10 s, while exerting respiratory effort conducted by chest and abdomen movements. Symptoms of OSA include excessive daytime sleepiness, fatigue, snoring, repeated microarousals, and headache upon awakening. Diagnosis of OSA is based on clinical symptoms and polysomnography (PSG) at sleep lab or at home (home sleep apnea testing—HSAT). Treatment of OSA includes continuous positive airway pressure (CPAP), oral appliances, and surgery, in addition to weight loss and sleep hygiene. Population-based studies have shown that the prevalence of OSA increases with age. Overall, the prevalence of people over 65 years old having sleep apnea is between 13 and 32%
[1]. A 10-year age augmentation is associated with an increase in the odds of having an AHI of 15 or greater, by 24%
[2]. Male gender and obesity are not important risk factors for OSA after the age of 50 years old. The male-to-female ratio for OSA in the elderly is 1:1.
The pathological mechanisms underlying OSA change with age. Aging is associated with an increase in pharyngeal collapsibility and in pharyngeal resistance during sleep, independent of body mass index (BMI) and gender
[3]. A decrease in the activity of the dilator muscles of the pharynx by the loss of tissue elasticity may contribute to pharyngeal collapse
[4]. The response of the genioglossus muscle to negative intrapharyngeal pressure during sleep is reduced
[5]. For older women, decreased levels of sex hormone may partly be responsible for increased collapsibility of the posterior oropharynx
[6].
2. Personalization of OSA with Clinical Approach in Elderly Patients
The clinical characteristics of OSA in older adults are probably different from those observed in younger ones. While the classic symptoms of OSA like apneas, nocturnal choking, and daytime sleepiness are witnessed, older patients are more likely to present with sleep complaints, nocturia, and cognitive dysfunction
[1][7]. Snoring may be less present or unrecognized in older people with OSA
[2]. Excessive daytime sleepiness (EDS) in older patients is less severe than in younger subjects with the same level of OSA severity. However, it may be difficult to evaluate sleepiness in older adults, because the Epworth Sleepiness Scale (ESS) is not a validated tool in this age group. There was evidence that ESS might underestimate sleepiness severity in older adults
[8]. Moreover, EDS in the elderly is highly influenced by pre-existing neurocognitive decline, comorbidities, and the use of medication.
Growing evidence suggests an increased risk of cognitive impairment in older adults with OSA. However, the results are heterogeneous because of differences in OSA definitions, types of neuropsychological tests, and variables adjusted for in statistical analyses. Attention, vigilance, memory, and executive function are the cognitive domains most commonly affected in OSA patients
[9]. Several factors associated with cognitive dysfunction are snoring, apneas, nocturnal hypoxemia, and AHI
[10]. There are hypothetical mechanisms which may explain the association between OSA and cognitive dysfunction. Repeated micro-arousals which happen during the sleep of OSA patients alter both sleep macro-architecture (time in stage 3 or deep sleep and REM sleep) and micro-structure (K-complexes, spindle and slow wave characteristics)
[9][10]. These factors have been proven to play important roles in neurogenesis, synaptic plasticity, memory formation, and consolidation
[11]. Therefore, chronic sleep alterations in OSA can negatively affect not only the cognitive functions but also changes in brain structure.
OSA has been known to be a risk factor of cerebro-cardiovascular diseases, including hypertension, congestive heart failure, stroke, arrhythmias, ischemic events, and pulmonary artery hypertension. However, these relationships are less evident in the elderly population. The cardiovascular risk was more likely to increase in younger (<65 years old) than older subjects in the Sleep Heart Health Study
[12]. Another prospective observational study showed that older patients (≥65 years old) with untreated severe OSA (AHI > 30/h) had increased all-cause and cardiovascular mortality
[13]. In one population-based cohort study in older patients (mean age 77 years), severe OSA (AHI ≥ 30/h) increased the risk of ischemic stroke, independently of known risk factors
[14].
In addition, OSA in elderly patients is associated with multiple potential consequences, including an increased risk of falls in older men, depression, and decreased quality of life, because of reduced social functioning and vitality
[15][16].
3. Personalized Treatment for OSA in Elderly Patients
Regarding the treatment of older adults with OSA, positional measures and oral appliances are recommended in mild-to-moderate OSA
[7]. Positive airway therapy or CPAP is the treatment of choice in patients with the moderate-to-severe or symptomatic form of OSA. There is not much evidence on the effectiveness of OSA with CPAP in this age group. A few studies have shown that CPAP may reduce daytime sleepiness, cardiovascular consequences, and cognitive outcomes
[17]. Concerning the patients’ compliance with CPAP, 30% of the elderly with OSA refuse it, and only about 41% remain adherent to their treatment after one year. In patients over 80 years old, the compliance with CPAP is very low (less than 3 h per night)
[17]. Adherence to CPAP therapy in older patients may be affected by factors such as cognitive impairment, medical and mood disturbances, nocturia, and lack of a supportive partner
[7]. Behavioral interventions can improve CPAP adherence in the elderly.
OSA is prevalent but underdiagnosed in older patients for many reasons, such as non-specific symptoms, comorbidities, polypharmacy, or the social belief of sleep problems as normal aging. The clinical presentation of OSA in older adults differs from that of younger patients. Female gender and obesity are not important risk factors in older adults. Polysomnography is the gold standard in the diagnosis of OSA in elderly. Respiratory polygraphy could be used in patients with comorbidities or neurocognitive decline. Moderate-to-severe OSA is associated with increased risk of cardiovascular diseases as well as cognitive impairment, and CPAP treatment may reduce the risk. However, compliance with CPAP in older patients is low. Considering the high prevalence and correlation with medical and mental comorbidities, health care practitioners should incorporate OSA screening in clinical practice.
This entry is adapted from the peer-reviewed paper 10.3390/jpm12122034