Evidence map›Paper›PMID 41680697›Full record

Observational studyBMC public health2026

Heat stress in relation to sleep health among farmers: a cross-sectional study.

Wensu Zhou, Symielle A Gaston, Bethany T Ogbenna, Christine G Parks, Dale P Sandler, Chandra L Jackson

Abstract readObservational Study
PubMed Full text at PMC Publisher
In one paragraph

Observational study in BMC public health, 2026. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Not yet cited in PubMed.

0numbers the graph read from it
0cells of the map it votes in
0citing papers in PubMed
–field-weighted citation impact
1 · What the graph read from it

What it found

Each row is one number read from the abstract, on the scale the paper reported it, with its interval. Left of the dashed line favours the treatment, right favours the comparator. Under each row is the sentence it came from. New to these charts? A ten-minute tutorial.

The abstract states no effect estimate the extractor could read, or names no intervention and outcome on the map, so this paper lights no cell and moves no belief. It is still indexed, cited and linked below.

2 · The registry

The trial behind it

Trials whose registry record cites this paper, or whose number appears in the abstract. A trial that started after this paper was published is citing it as background, not reporting it.

Neither the registry nor the abstract names a trial number. If this is a trial report, that itself is worth knowing.

3 · Its place in the literature

Who cites it

0 citing papers in PubMed.

No citing paper in PubMed yet.

4 · The record

Corrections and comments

5 · Who and what money

Authors and funding

6 authors.

Wensu ZhouEpidemiology Branch, National Institute of Environmental Health Sciences, Department of Health and Human Services, National Institutes of Health, 111 TW Alexander Drive, MD A3-05, NC, Research Triangle Park, 27709, USA.
Symielle A GastonEpidemiology Branch, National Institute of Environmental Health Sciences, Department of Health and Human Services, National Institutes of Health, 111 TW Alexander Drive, MD A3-05, NC, Research Triangle Park, 27709, USA.
Bethany T OgbennaEpidemiology Branch, National Institute of Environmental Health Sciences, Department of Health and Human Services, National Institutes of Health, 111 TW Alexander Drive, MD A3-05, NC, Research Triangle Park, 27709, USA.
Christine G ParksEpidemiology Branch, National Institute of Environmental Health Sciences, Department of Health and Human Services, National Institutes of Health, 111 TW Alexander Drive, MD A3-05, NC, Research Triangle Park, 27709, USA.
Dale P SandlerEpidemiology Branch, National Institute of Environmental Health Sciences, Department of Health and Human Services, National Institutes of Health, 111 TW Alexander Drive, MD A3-05, NC, Research Triangle Park, 27709, USA.
Chandra L JacksonEpidemiology Branch, National Institute of Environmental Health Sciences, Department of Health and Human Services, National Institutes of Health, 111 TW Alexander Drive, MD A3-05, NC, Research Triangle Park, 27709, USA. Chandra.Jackson@nih.gov.

Funding

National Institutes of Health NIH Z01ES049030 (DPS)NIEHS NIH HHS Z1AES103325 (CLJ)
6 · The paper itself

Abstract

backgroundHeat exposure has been linked to sleep disturbances in the general population, but farmers, who are particularly vulnerable due to outdoor occupational exposures-have been rarely studied in this context. this study aimed to investigate associations between heat stress and sleep health among farmers.

methodsWe conducted cross-sectional analyses of 8,203 male farmers from Iowa (78%) and North Carolina (NC, 22%) in the Agricultural Health Study (2013-2015). Daily wet bulb globe temperatures (WBGT) from May 2013-September 2015 was used. We calculated absolute heat stress by averaging WBGT over 2/5/7 days before the interview. Relative heat stress (i.e., the difference between absolute heat stress and the 92.5th percentile of WBGT) was also calculated. WBGT was categorized by heat stress risk (low, moderate, high). Sleep outcomes included short sleep (< 7 h), daytime sleepiness (≥ 3 days/week), napping (yes), and long naps (≥ 30 min). Poisson regression with robust variance estimated adjusted prevalence ratios (PRs) and 95% confidence intervals (CIs), stratified by state.

resultsFarmers averaged 63 years old (SD = 10.1); 37.8% reported short sleep, 8.1% daytime sleepiness, 44.6% napping, and 17.1% long naps. Mean absolute WBGT were 70.4 °F (SD = 6.36) in Iowa and 77.7 °F (SD = 7.83) in NC. In Iowa, moderate heat stress (2-day average) was associated with higher short sleep prevalence (PR = 1.04 [1.00-1.07]). In NC, higher absolute (2-/5-/7-day average) and relative WBGT (2-day average), as well as moderate (2-/7-day) and high (2-day) heat stress were associated with daytime napping (e.g., PR

conclusionsHeat stress was associated with a small/weak but potentially meaningful relationship with poor self-reported sleep among farmers. Future studies using objective sleep measures are needed. Although our findings highlight the potential importance of incorporating heat mitigation and sleep health strategies into occupational safety guidelines for agricultural workers, the cross-sectional design of this study precludes causal conclusions.

Indexed as

FarmersHeat Stress DisordersOccupational ExposureSleep Wake DisordersAdultCross-Sectional StudiesHot TemperatureHumansIowaMaleMiddle AgedNorth CarolinaSleep DurationAgricultural workersHeat stressSleep durationSleep quality

Identifiers

PMID41680697
PMCPMC13005482

What OpenQuestion holds

Textmetadata
LicenceCC BY
Read underepoch 390

Registered trials

None linked

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.