{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,1]],"date-time":"2026-10-01T04:32:03Z","timestamp":1790829123637,"version":"4.1.0"},"reference-count":42,"publisher":"MDPI AG","issue":"2","license":[{"start":{"date-parts":[[2022,1,12]],"date-time":"2022-01-12T00:00:00Z","timestamp":1641945600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["IJERPH"],"abstract":"<jats:p>Purpose: This study assesses the potential acute effects of heatwaves on human morbidities in primary care settings. Methods: We performed a time-stratified case-crossover study to assess the acute effects of heatwaves on selected morbidities in primary care settings in Flanders, Belgium, between 2000 and 2015. We used conditional logistic regression models. We assessed the effect of heatwaves on the day of the event (lag 0) and X days earlier (lags 1 to X). The associations are presented as Incidence Density Ratios (IDR). Results: We included 22,344 events. Heatwaves are associated with increased heat-related morbidities such as heat stroke IDR 3.93 [2.94\u20135.26] at lag 0, dehydration IDR 3.93 [2.94\u20135.26] at lag 1, and orthostatic hypotension IDR 2.06 [1.37\u20133.10] at lag 1. For cardiovascular morbidities studied, there was only an increased risk of stroke at lag 3 IDR 1.45 [1.04\u20132.03]. There is no significant association with myocardial ischemia\/infarction or arrhythmia. Heatwaves are associated with decreased respiratory infection risk. The IDR for upper respiratory infections is 0.82 [0.78\u20130.87] lag 1 and lower respiratory infections (LRI) is 0.82 [0.74\u20130.91] at lag 1. There was no significant effect modification by age or premorbid chronic disease (diabetes, hypertesnsion). Conclusion: Heatwaves are associated with increased heat-related morbidities and decreased respiratory infection risk. The study of heatwaves\u2019 effects in primary care settings helps evaluate the impact of heatwaves on the general population. Primary care settings might be not suitable to study acute life-threatening morbidities.<\/jats:p>","DOI":"10.3390\/ijerph19020832","type":"journal-article","created":{"date-parts":[[2022,1,12]],"date-time":"2022-01-12T23:17:07Z","timestamp":1642029427000},"page":"832","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":19,"title":["The Effects of Heatwaves on Human Morbidity in Primary Care Settings: A Case-Crossover Study"],"prefix":"10.3390","volume":"19","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-0027-1073","authenticated-orcid":false,"given":"Mahmoud","family":"Alsaiqali","sequence":"first","affiliation":[{"name":"Epidemiology and Social Medicine (ESOC), University of Antwerp, 2610 Antwerp, Belgium"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Katrien","family":"De Troeyer","sequence":"additional","affiliation":[{"name":"Department of Public Health and Primary Care, KU Leuven, 3000 Leuven, Belgium"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Lidia","family":"Casas","sequence":"additional","affiliation":[{"name":"Epidemiology and Social Medicine (ESOC), University of Antwerp, 2610 Antwerp, Belgium"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-4419-5757","authenticated-orcid":false,"given":"Rafiq","family":"Hamdi","sequence":"additional","affiliation":[{"name":"Royal Meteorological Institute of Belgium, B-1180 Brussels, Belgium"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-1878-9869","authenticated-orcid":false,"given":"Christel","family":"Faes","sequence":"additional","affiliation":[{"name":"Data Science Institute (DSI), I-BioStat, Hasselt University, BE-3500 Hasselt, Belgium"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Gijs","family":"Van Pottelbergh","sequence":"additional","affiliation":[{"name":"Department of Public Health and Primary Care, KU Leuven, 3000 Leuven, Belgium"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2022,1,12]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","unstructured":"Intergovernmental Panel on Climate Change (2014). 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