Evidence map›Paper›PMID 42273732›Full record

ArticleChronic respiratory disease

Diurnal and seasonal variation in six-minute walk distance in pulmonary hypertension: Implications for clinical monitoring.

Lucy Robertson, Katherine Bunclark, Mark Toshner, Joanna Pepke-Zaba, Karen Sheares, John Cannon, Dolores Taboada Buasso, Karl P Sylvester, Joseph Newman, Benjamin Knox-Brown

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Article in Chronic respiratory disease. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Not yet cited in PubMed.

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2 · The registry

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3 · Its place in the literature

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4 · The record

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5 · Who and what money

Authors and funding

10 authors.

Lucy RobertsonRespiratory Physiology, Royal Papworth Hospital, Cambridge, UK.ORCID 0000-0002-4635-9698
Katherine BunclarkPulmonary Vascular Disease Unit, Royal Papworth Hospital, Cambridge, UK.
Mark ToshnerPulmonary Vascular Disease Unit, Royal Papworth Hospital, Cambridge, UK.
Joanna Pepke-ZabaPulmonary Vascular Disease Unit, Royal Papworth Hospital, Cambridge, UK.
Karen ShearesPulmonary Vascular Disease Unit, Royal Papworth Hospital, Cambridge, UK.
John CannonPulmonary Vascular Disease Unit, Royal Papworth Hospital, Cambridge, UK.
Dolores Taboada BuassoPulmonary Vascular Disease Unit, Royal Papworth Hospital, Cambridge, UK.
Karl P SylvesterRespiratory Physiology, Royal Papworth Hospital, Cambridge, UK.
Joseph NewmanPulmonary Vascular Disease Unit, Royal Papworth Hospital, Cambridge, UK.
Benjamin Knox-BrownRespiratory Physiology, Royal Papworth Hospital, Cambridge, UK.

Funding

No grant is acknowledged in the PubMed record.

6 · The paper itself

Abstract

IntroductionThe American Thoracic Society (ATS) six-minute walk test (6MWT) guidelines recommend repeat testing at the same time of day to minimise intraday variability. Whether diurnal or seasonal factors affect the 6MWT in pulmonary hypertension (PH) is unclear. We investigated associations between six-minute walk distance (6MWD) and secondary 6MWT parameters with time of day and season using cross sectional and longitudinal analyses.MethodsThis single-centre retrospective study (2019-2025) included PH patients undergoing 6MWT as per ATS guidelines. Cross-sectional analyses compared morning (AM, 07:00-12:00) vs afternoon (PM, 12:01-18:00) and seasonal effects on 6MWD using adjusted linear models. Longitudinal effects were examined with adjusted linear mixed effects models.ResultsThe cross-sectional cohort included 1,665 patients (AM n=734, PM n=931). Estimated marginal mean (EMM) 6MWD was higher in the morning than afternoon (354m vs 339m; p=0.005), with no seasonal variation (Winter 338m, Spring 354m, Summer 345m, Autumn 343m; p=0.20). The longitudinal cohort included 554 patients. EMM 6MWD was similar between AM and PM (396m vs 400m; p=0.16) and across seasons (Winter 395m, Spring 395m, Summer 399m, Autumn 398m; p=0.43). Maximal heart rate (MHR) was higher in the afternoon (115 vs 113 bpm; p=0.002) and lower in Summer/Autumn (113 bpm) vs Winter (116 bpm) and Spring (115 bpm; p=0.017).Conclusion6MWD was stable across time of day and season, supporting greater flexibility in scheduling 6MWTs than suggested by guidelines. Small variations in MHR were associated with circadian and seasonal influences but did not affect 6MWD. Prospective studies are needed to confirm these findings.

Indexed as

Circadian RhythmHypertension, PulmonarySeasonsWalk TestAgedCross-Sectional StudiesFemaleHumansLongitudinal StudiesMaleMiddle AgedRetrospective Studies6MWTdiurnal variationpulmonary hypertensionseason

Identifiers

PMID42273732
PMCPMC13260776

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Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.