Journal article
The effect of the participatory heat education and awareness tools (HEAT) intervention on agricultural worker physiological heat strain: results from a parallel, comparison, group randomized study
BMC public health, Vol.22(1), 1746
09/15/2022
DOI: 10.1186/s12889-022-14144-2
PMCID: PMC9476265
PMID: 36104813
Abstract
Farmworkers are at risk of heat-related illness (HRI). We sought to: 1) evaluate the effectiveness of farmworker Spanish/English participatory heat education and a supervisor decision-support mobile application (HEAT intervention) on physiological heat strain; and 2) describe factors associated with HRI symptoms reporting.
We conducted a parallel, comparison group intervention study from May-September of 2019 in Central/Eastern Washington State, USA. We used convenience sampling to recruit adult outdoor farmworkers and allocated participating crews to intervention (n = 37 participants) and alternative-training comparison (n = 38 participants) groups. We measured heat strain monthly using heart rate and estimated core body temperature to compute the maximum work-shift physiological strain index (PSI
) and assessed self-reported HRI symptoms using a weekly survey. Multivariable linear mixed effects models were used to assess associations of the HEAT intervention with PSI
, and bivariate mixed models were used to describe factors associated with HRI symptoms reported (0, 1, 2+ symptoms), with random effects for workers.
We observed larger decreases in PSI
in the intervention versus comparison group for higher work exertion levels (categorized as low, low/medium-low, and high effort), after adjustment for maximum work-shift ambient Heat Index (HI
), but this was not statistically significant (interaction - 0.91 for high versus low/medium-low effort, t = - 1.60, p = 0.11). We observed a higher PSI
with high versus low/medium-low effort (main effect 1.96, t = 3.81, p < 0.001) and a lower PSI
with older age (- 0.03, t = - 2.95, p = 0.004), after covariate adjustment. There was no clear relationship between PSI
and the number of HRI symptoms reported. Reporting more symptoms was associated with older age, higher HI
, 10+ years agricultural work, not being an H-2A guest worker, and walking > 3 min to get to the toilet at work.
Effort level should be addressed in heat management plans, for example through work/rest cycles, rotation, and pacing, in addition to education and other factors that influence heat stress. Both symptoms and indicators of physiological heat strain should be monitored, if possible, during periods of high heat stress to increase the sensitivity of early HRI detection and prevention. Structural barriers to HRI prevention must also be addressed.
ClinicalTrials.gov Registration Number: NCT04234802 , date first posted 21/01/2020.
Details
- Title: Subtitle
- The effect of the participatory heat education and awareness tools (HEAT) intervention on agricultural worker physiological heat strain: results from a parallel, comparison, group randomized study
- Creators
- Erica Chavez Santos - University of WashingtonJune T Spector - University of WashingtonJared Egbert - University of WashingtonJennifer Krenz - University of WashingtonPaul D Sampson - University of WashingtonPablo Palmández - University of WashingtonElizabeth Torres - Education NorthwestMaria Blancas - University of WashingtonJose Carmona - University of WashingtonJihoon Jung - University of WashingtonJohn C Flunker - University of Washington
- Resource Type
- Journal article
- Publication Details
- BMC public health, Vol.22(1), 1746
- DOI
- 10.1186/s12889-022-14144-2
- PMID
- 36104813
- PMCID
- PMC9476265
- NLM abbreviation
- BMC Public Health
- ISSN
- 1471-2458
- eISSN
- 1471-2458
- Grant note
- T42 OH008433 / NIOSH CDC HHS T32 ES015459 / NIEHS NIH HHS U54 OH007544 / NIOSH CDC HHS
- Language
- English
- Date published
- 09/15/2022
- Academic Unit
- Epidemiology
- Record Identifier
- 9984738105602771
Metrics
7 Record Views