# Obstructive sleep apnea in community-dwelling polio survivors: a 5-year longitudinal follow-up study

## TL;DR

This study tracked OSA progression in polio survivors over 5 years and found worsening OSA parameters linked to BMI and scoliosis.

## Contribution

Longitudinal analysis of OSA progression in polio survivors with comparison to controls and identification of correlates like BMI and scoliosis.

## Key findings

- OSA severity increased over 5 years in polio survivors, with rising ODI4 and AHI.
- Polio survivors showed increased mixed apnea and prolonged REM sleep latency.
- ODI4 changes correlated with scoliosis and BMI fluctuations.

## Abstract

Obstructive sleep apnea (OSA) is highly prevalent in polio survivors, but longitudinal data on its progression remain limited. This study aimed to characterize OSA progression in community-dwelling polio survivors and compare it with an age-matched control group.

A prospective 5-year longitudinal study recruited 148 polio survivors (48.76 ± 5.97 years, 75% male). At baseline (2014), all participants underwent overnight oximetry. Among them, 42 completed in-lab polysomnography (PSG) testing. Over the 5-year follow-up, 112 polio survivors (76.79% male, mean age 48.48 ± 6.05 years) were successfully tracked, with 33 undergoing follow-up PSG. Additionally, 59 age- and sex-matched OSA patients were enrolled as controls. Primary outcomes included changes in oxygen desaturation index ≥4% (ODI4) and apnea-hypopnea index (AHI). Correlates of OSA progression were analyzed using Pearson’s correlations.

Over 5 years, ODI4 increased significantly in polio survivors from 8.11 ± 9.13 to 10.35 ± 11.63 events/h (p = 0.01), with a shift toward moderate–severe ODI4 (13 to 22%, p = 0.027). AHI also rose in both groups: polio survivors (26.57 ± 21.25 to 33.86 ± 22.43 events/h, p = 0.02) and controls (27.14 ± 21.91 to 37.24 ± 24.55 events/h, p = 0.004), with no significant group difference in AHI progression (p = 0.89). However, polio survivors showed increased mixed apnea index (p = 0.02) and prolonged REM sleep latency (p = 0.009). ODI4 changes correlated with scoliosis (r = 0.27, p = 0.005) and BMI fluctuations (r = 0.25, p = 0.008).

OSA-related parameters, particularly mixed apnea and REM alterations, progress in polio survivors. Changes in ODI4 were positively correlated with BMI fluctuations and scoliosis.