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The utility of home sleep apnea tests in patients with low versus high pre-test probability for moderate to severe OSA

Abstract

Purpose

Home sleep apnea tests (HSATs) are an alternative to attended polysomnograms (PSGs) when the pre-test probability for moderate to severe OSA is high. However, insurers often mandate use anytime OSA is suspected regardless of the pre-test probability. Our objective was to determine the ability of HSATs to rule in OSA when the pre-test probability of an apnea hypopnea index (AHI) in the moderate to severe range is low.

Methods

Patients who underwent HSATs were characterized as low or high pre-test probability based on the presence of two symptoms of the STOP instrument plus either BMI > 35 or male gender. The odds of HSAT diagnostic for OSA dependent on pre-test probability was calculated. Stepwise selection determined predictors of non-diagnostic HSAT. As PSG is performed after HSATs that do not confirm OSA, false negative results were assessed.

Results

Among 196 individuals, pre-test probability was low in 74 (38%) and high in 122 (62%). A lower percentage of individuals with a low versus high pre-test probability for moderate to severe OSA had HSAT results that confirmed OSA (61 versus 84%, p = 0.0002) resulting in an odds ratio (OR) of 0.29 for confirmatory HSAT in the low pre-test probability group (95% CI [0.146, 0.563]). Multivariate logistic regression demonstrated that age ≤ 50 (OR 3.10 [1.24–7.73]), female gender (OR 3.58[1.50–8.66]), non-enlarged neck circumference (OR 11.50 [2.50–52.93]), and the absence of loud snoring (OR 3.47 [1.30–9.25]) best predicted non-diagnostic HSAT. OSA was diagnosed by PSG in 54% of individuals with negative HSAT which was similar in both pre-test probability groups.

Conclusion

HSATs should be reserved for individuals with high pre-test probability for moderate to severe disease as opposed to any individual with suspected OSA.

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Acknowledgements

The authors wish to thank Ronald D. Chervin, MD, MS for advice on data analysis and review of the manuscript, and Casey Cox, RPSGT for assistance with database queries.

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Correspondence to Cathy A. Goldstein.

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All procedures performed in studies involving human participants were in accordance with the ethical standards of the institutional research committee (University of Michigan IRBMED) and with the 1964 Helsinki declaration and its later amendments or comparable ethical standards. For this type of study formal consent is not required.

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Goldstein, C.A., Karnib, H., Williams, K. et al. The utility of home sleep apnea tests in patients with low versus high pre-test probability for moderate to severe OSA. Sleep Breath 22, 641–651 (2018). https://doi.org/10.1007/s11325-017-1594-2

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Keywords

  • Obstructive sleep apnea
  • Home sleep apnea test
  • Polysomnogram
  • Pre-test probability