IGF-1: a potential biomarker for efficacy of sleep improvement with automatic airway pressure therapy for obstructive sleep apnea?
BACKGROUND
Positive airway pressure (PAP) reverses obstructive sleep apnea (OSA)-related hypoxia and restores slow wave sleep (SWS). Insulin-like growth factor 1 (IGF-1) is a neuropeptide that facilitates the repair of neurons from hypoxia and improves sleep regulation. IGF-1 concentrations are lower in OSA, and likely increase following PAP treatment; however, this relationship has not yet been determined in a younger cohort of OSA patients.


METHODS
This was a prospective, observational pilot study of 58 young men, who were diagnosed with OSA and provided PAP as an intervention. Adherence to PAP treatment over 3 months was objectively measured, as well as changes in the apnea-hypopnea index (AHI). Serum concentrations of IGF-1and C-reactive protein (CRP) were measured and correlated with PAP adherence.


RESULTS
IGF-1 concentrations at baseline were similar between PAP adherent 55.5 ± 34.4 ng/ml and PAP nonadherent participants 61.2 ± 27.1 ng/ml (p = 0.4), with the overall mean IGF-1 concentration of 59.0 ± 29.9 ng/ml. At follow-up, adherent participants had concentrations of IGF-1 that were significantly higher 128 ± 59.5 ng/ml compared to nonadherent participants 86.0 ± 47.4 ng/ml (p < 0.01). Increases in IGF-1 concentrations were significantly associated with reductions in AHI (Spearman's rho = -0.409, p = 0.015). Conversely, CRP concentrations did not differ between baseline and follow-up measurements in either group.


CONCLUSIONS
Adherence to PAP treatment leads to significant increases in IGF-1 concentrations in young men with OSA. While an objective measure of adherence exists, PAP usage does not allow for measure of sleep improvement. IGF-1 may serve as a potential biomarker for the efficacy of PAP therapy on improved sleep.
Medical Specialties Clinic, 121st General Hospital, Unit #15281, APO AP, 96205-5281, Seoul, Korea.
Vincent
V
Mysliwiec
National Institute of Nursing Research, National Institutes of Health, 10 Center Drive, Bethesda, MD, 20892, USA.
Jessica
J
Gill
Department of Operations Research, Naval Postgraduate School, 1411 Cunningham Road, Monterey, CA, 93943, USA.
Panagiotis
P
Matsangas
Department of Pulmonary, Critical Care, Sleep Medicine, Madigan Army Medical Center, 9040A Fitzsimmons Avenue, Tacoma, WA, 98431, USA.
Tristin
T
Baxter
West Virginia University, 1 Medical Center Drive, Morgantown, WV, 26506, USA.
Taura
T
Barr
Department of Pulmonary, Critical Care, Sleep Medicine, Madigan Army Medical Center, 9040A Fitzsimmons Avenue, Tacoma, WA, 98431, USA. bernard.j.roth.civ@mail.mil.
Bernard J
BJ
Roth
D000328:Adult; D000367:Age Factors; D015415:Biomarkers / Q000097:blood*; D015331:Cohort Studies; D006801:Humans; D007334:Insulin-Like Growth Factor I / Q000378:metabolism*; D054542:Iraq War, 2003-2011; D008297:Male; D008889:Military Personnel; D017286:Polysomnography; D011175:Positive-Pressure Respiration / Q000379:methods*; D011446:Prospective Studies; D020181:Sleep Apnea, Obstructive / Q000097:blood* / Q000628:therapy*; D016896:Treatment Outcome; D055815:Young Adult
D015415:Biomarkers; D007334:Insulin-Like Growth Factor I
Adherence; Insulin-like growth factor (IGF-1); Obstructive sleep apnea; Positive airway pressure (PAP)