Nocturnal hypoxia and age‐related macular degeneration

Abstract

AbstractBackgroundNocturnal hypoxia is common, under‐diagnosed and is found in the same demographic at risk of age‐related macular degeneration (AMD). The objective of this study was to determine any association between nocturnal hypoxia and AMD, its severity, and the high‐risk sub‐phenotype of reticular pseudodrusen (RPD).MethodsThis cross‐sectional study included participants aged ≥50 years with AMD, or normal controls, exclusive of those on treatment for obstructive sleep apnoea. All participants had at home, overnight (up to 3 nights) pulse oximetry recordings and multimodal imaging to classify AMD. Classification of Obstructive Sleep Apnea (OSA) was determined based on oxygen desaturation index [ODI] with mild having values of 5–15 and moderate‐to‐severe >15.ResultsA total of 225 participants were included with 76% having AMD, of which 42% had coexistent RPD. Of the AMD participants, 53% had early/intermediate AMD, 30% had geographic atrophy (GA) and 17% had neovascular AMD (nAMD). Overall, mild or moderate‐to‐severe OSAwas not associated with an increased odds of having AMD nor AMD with RPD (p ≥ 0.180). However, moderate‐to‐severe OSA was associated with increased odds of having nAMD (odds ratio = 6.35; 95% confidence interval = 1.18 to 34.28; p = 0.032), but not early/intermediate AMD or GA, compared to controls (p ≥ 0.130). Mild OSA was not associated with differences in odds of having AMD of any severity (p ≥ 0.277).ConclusionsThere was an association between nocturnal hypoxia as measured by the ODI and nAMD. Hence, nocturnal hypoxia may be an under‐appreciated important modifiable risk factor for nAMD.