Lung Disease and Sleep Disordered Breathing
- Increase OSA prevalence in Asthma (2-6x more common in asthma)
- Less common by HST but likely because you can't actually measure sleep apnea in HST
- HST underestimates OSA prevalence
- Prospective data that suggests that asthma was a risk factor for incidence of OSA (39%) 4 years later
- Relationship with duration of asthma and development of OSA
- having asthma for >10 years was a/w highest risk for OSA development
- Therefore asthma in in of it self can develop OSA
- each 5 year increment of ...
- Using ICS in a dose dependent fashion was a/w high OSA risk
- 5 fold increase risk
- How?
- ? ICS may lead to genioglossus dysfunction
- ? ICS may lead to fat deposition to the posterior oropharynx
- After 4months. increase protrusive strength of the tongue but cannot sustain this (decrease sustain)
- similar to untreated OSA patients
- increase in upper airway collapsibility during sleep
- increase fat accumulaton in the neck by 21% (measured by MRI)
- no weight gain in these subjects
- ICS effects
- structural changesin the tongye (muscle fiber shifts, laminin) and neck (fat) whcih alter the uniform contraction and balanced co-activation of key muscle groups
- Tongue function and muscle fiber shifts - osa patients
- Clinical implicaitons
- predispositon to collapse during sleep and potnetial delteriouss effects on other uaw functions
- OSA shifts asthma phenotype to more non-eosinophilic
- Apneas resulting in intrathoraicc pressure swings → mechnical stress on the lower airways
- Summary Asthma / OSA
- OSA-2.6x more common in asthma:
- HSS underestimate OSA prevalence
- IS use may contribute, apart from other disease-related features
- OSA influences asthma control:
- Similar relationships with day- and night-time asthma control
- CPAP for OSA improves asthma control indices and QoL, but not FEV, (?remodeling)
- Underlying mechanisms relate to OSA's features:
- CIH:
- shifts the inflammation towards less eosinophilic, Th-1 pathways associated with tissue remodeling led to airways obstruction, which may be irreversible
- Mechanical stress and sleep fragmentation may also contribute
- OSA prevalence in IPF is high and often unrecognized
- Symptoms and questionnaires have poor predictive ability in IPF
- Potential improved survival in IPF with adherent CPAP treatment for OSA
- OSA is highly common in IPF and largely unrecognized symptoms are not predictive of the diagnosis, thus, formal sleep evaluation should be considered
- OSA relates with worse IPF outcomes and survival:
- in part, through a contribution to the RV dysfunction
- OSA features (hypoxia, pressure swings) could affect various lung compartments (parenchyma, capillary bed), such that the combined effect is worse pulmonary & RV dysfunction, and gas exchange
- Data are limited and larger/mechanistic studies are needed
- Addressing OSA early offers a glimpse of hope in a disease with a grim prognosis