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PubMed · 12662012

Ageing does not influence the sleep-related decrease in the hypercapnic ventilatory response.

H A K Browne·L Adams·A K Simonds·M J Morrell
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Abstract

In young people, a sleep-related reduction in the gain of the ventilatory chemoreflex feedback loop occurs; in the elderly, it has been reported that no sleep-related reduction occurs. A relatively high loop gain could contribute to periodic breathing and central sleep apnoea in the elderly. This study tested the hypothesis that ageing is associated with a reduction in the magnitude of the sleep-related decrease in the hypercapnic ventilatory response (HCVR). The HCVR was measured using a steady state method, awake and asleep, in groups (n = 10) of elderly (66-81 yrs) and young (23-35 yrs) nonapnoeics. Upper airway resistance was maintained close to wakefulness levels using continuous positive airway pressure (mean sleep-related increase in resistance: elderly 1.6 +/- 1.2 cmH2O L x s(-1), young 1.2 +/- 0.8 cmH2O x L x s(-1)). The sleep-related decrease in the HCVR was similar in the elderly and young groups (elderly: wake 0.14 +/- 0.06 and sleep 0.06 +/- 0.02 L min(-1) x kPa and young, wake 0.19 +/- 0.07 and sleep 0.10 +/- 0.04 L x min(-1) x kPa). Ageing per se was shown not to change the magnitude of the sleep-related decrease in hypercapnic ventilatory response. The authors speculate that age-related changes in the hypercapnic ventilatory response are unlikely to contribute to the increased prevalence of central sleep apnoea in the elderly.

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AgedAged, 80 and overAgingAnalysis of VarianceBlood PressureCarbon DioxideChemoreceptor CellsFemaleHumansHypercapniaMaleProbabilityPulmonary VentilationSampling StudiesSensitivity and SpecificitySleep Apnea SyndromesSleep DeprivationWakefulnessComparative StudyJournal ArticleResearch Support, Non-U.S. Gov't

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H A K Browne, L Adams, A K Simonds, M J Morrell. 2003. Ageing does not influence the sleep-related decrease in the hypercapnic ventilatory response.. https://doi.org/10.1183/09031936.03.00039002

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