Categories: Swimming

Steered Novel Risk Factors for Swimming-Induced Pulmonary Edema: Asthma and Restricted Open Water Swimming Experience

This web page was created programmatically, to learn the article in its authentic location you may go to the hyperlink bellow:
https://pmc.ncbi.nlm.nih.gov/articles/PMC13494432/
and if you wish to take away this text from our website please contact us

Abstract

Background

Swimming-induced pulmonary edema (SIPE) has gained rising consideration in recent times. However, danger components for SIPE stay incompletely understood, and current information are based totally on small-scale research.

Research Question

Which particular person danger components are related to SIPE?

Study Design and Methods

We carried out a case-control examine based mostly on Sweden’s largest open water swimming occasion, Vansbrosimningen. Data have been obtained via interviews with people identified with SIPE in 2017 to 2024 and thru a web-based survey administered to manage individuals with out SIPE. Individual components related to SIPE have been recognized by utilizing a number of logistic regression.

Results

A complete of 258 circumstances identified with SIPE and a pair of,117 management individuals have been included. A primary logistic regression mannequin recognized feminine intercourse (OR, 5.3; 95% CI, 3.6-7.7), greater age (OR for age ≥ 61 years, 7.3; 95% CI, 3.8-14.2), hypertension (OR, 1.9; 95% CI, 1.2-3.2), coronary heart illness (OR, 6.0; 95% CI, 2.5-14.2), bronchial asthma (OR, 1.7; 95% CI, 1.2-2.6), and low frequency of open water swimming throughout the present season (OR for by no means, 3.6; 95% CI, 2.4-5.4) as independently related to SIPE. A second mannequin discovered that earlier respiratory signs throughout open water swimming (OR, 3.5; 95% CI, 2.3-5.2) and acute respiratory tract an infection (OR, 10.2; 95% CI, 5.2-20.2) have been additionally strongly related to SIPE; nonetheless, the affiliation with bronchial asthma failed statistical significance on this mannequin.

Interpretation

This examine confirms beforehand reported particular person danger components for SIPE and immersion pulmonary edema: feminine intercourse, greater age, hypertension, coronary heart illness, respiratory tract an infection, and prior episodes. The information additionally recommend that bronchial asthma and restricted expertise of open water swimming are related to an elevated danger of SIPE. A complete understanding of the chance components for SIPE will enhance security throughout open water swimming and contribute to the event of medical pointers for SIPE.

Key Words: bronchial asthma, coronary heart illnesses, hypertension, immersion pulmonary edema, respiratory tract infections, danger issue, intercourse, SIPE, swimming, swimming-induced pulmonary edema

Graphical Abstract

FOR EDITORIAL COMMENT, SEE PAGE 297

Take-Home Points.

Research Question: Which particular person danger components are related to swimming-induced pulmonary edema (SIPE)?

Results: Based on a big cohort of open water swimmers, we confirmed feminine intercourse, greater age, hypertension, coronary heart illness, acute respiratory tract an infection, and former respiratory signs throughout open water swimming as danger components for SIPE and additional recommend that bronchial asthma and restricted expertise of open water swimming are related to an elevated danger of SIPE.

Interpretation: Two danger components for SIPE are advised right here that haven’t beforehand been described within the literature: bronchial asthma and restricted expertise of open water swimming.

Swimming-induced pulmonary edema (SIPE) is a subgroup of immersion pulmonary edema (IPE) often occurring throughout open water swimming.¹ The signs of SIPE embody cough, dyspnea, exhaustion, elevated sputum, and hemoptysis.²

The pathophysiology of SIPE is just not fully understood, though a number of potential danger components have been mentioned.²^,³^,⁴^,⁵ In our earlier research carried out throughout Sweden’s largest open water swimming occasion, Vansbrosimningen, SIPE was extra incessantly noticed in feminine people and in these of older age, which is according to different research of SIPE and IPE.⁶^,⁷^,⁸^,⁹^,¹⁰^,¹¹^,¹² We additionally noticed a better prevalence of bronchial asthma in sufferers with SIPE than within the common inhabitants.⁷ Furthermore, associations between SIPE and preexisting hypertension, cardiovascular comorbidities, smaller lung volumes, historical past of SIPE, colonization with respiratory pathogens, use of fish oil/omega 3 fatty acids, low water temperature, lengthy course distance, and overhydration have been advised.³^,⁴^,⁵^,⁷^,⁹^,¹⁰^,¹¹^,¹²^,¹³^,¹⁴ In divers with IPE, psychological stress, wetsuit use, bodily exertion, and water aspiration have been proposed as related components.¹¹^,¹²^,¹⁵

However, information of particular person danger components for creating SIPE throughout open water swimming stays restricted.¹⁴^,¹⁶ Identifying individuals prone to SIPE might improve particular person security and counseling and supply insights into pathophysiological mechanisms. Vansbrosimningen gives a singular chance for extending our information of SIPE and the goal of the present examine was to research particular person components related to a SIPE prognosis throughout the occasion in 2017 to 2024.

Study Design and Methods

Setting

Vansbrosimningen takes place yearly in cold-water rivers (16 °C-20 °C) surrounding Vansbro in central Dalecarlia, Sweden; it attracts about 10,000 people yearly. In the present examine, the individuals swum distances of 1,000, 1,500, and three,000 m within the 2017 to 2019 occasions, with the addition of 10,000 m within the 2022 to 2024 occasions. The imply water temperature was 18.1 °C (±1.4 °C) and air temperature 17.4 °C (±2.5 °C) throughout the occasion days. The well being care group consisted of a primary help staff, ambulances, and a cell medical unit with physicians and nurses.⁶^,⁷^,¹⁷^,¹⁸

Study Design and Population

In this case-control examine, circumstances have been sufferers identified with SIPE throughout Vansbrosimningen in 2017 to 2019 and 2022 to 2024 (the occasion was cancelled in 2020 and 2021 as a result of COVID-19 pandemic). Control individuals have been swimmers aged ≥ 18 years who accomplished 1,000 to three,000 m throughout the 2019 Vansbrosimningen occasion, with out being identified with SIPE. Due to uncertainty relating to whether or not the occasion would resume in its authentic format after the COVID-19 pandemic, management individuals have been recruited solely from the 2019 occasion.

Among swimmers (aged ≥ 18 years) who sought medical consideration for cough and/or dyspnea, SIPE was identified based mostly on findings of pulmonary edema on lung ultrasound (195 sufferers).⁶^,¹⁸ When lung ultrasound information weren’t out there (predominantly in 2017), the SIPE prognosis was based mostly on a medical algorithm incorporating peripheral oxygen saturation ≤ 95% and the presence of crackles on lung auscultation (63 sufferers).⁶^,⁷^,¹⁸ Patients with repeated SIPE episodes have been included solely on the first event. Control individuals have been instructed to refer solely to the longest race they participated in throughout 2019, if that they had participated in additional than 1 race. Control individuals who reported respiratory signs suggestive of SIPE throughout Vansbrosimningen or some other swimming occasion have been excluded (Fig 1).

Figure 1.

Flowchart inclusion of circumstances and management individuals from Vansbrosimningen. ^aIncluded races: Funktionärssimmet, Halvsimmet, Kortsimmet, Tjejsimmet, Öppen älv, and Vansbrosimmet; the ten,000 m race is included for the years 2022 to 2024. ^bYear 2017, 2018, 2022, 2023, and 2024. ^cEarlier reported pulmonary edema/SIPE or reported SIPE as the reason for discontinuation of the race. SIPE = swimming-induced pulmonary edema.

Ethical approvement was acquired from The Regional Ethical Review Board in Uppsala and The Swedish Ethical Review Authority, Sweden (Dnr 2017/216, 217/216/1, 2017/216/2, 2020-02265, 2021-01708), and all individuals gave written knowledgeable consent.

Data Collection

For circumstances, information on danger components have been collected instantly following the race and through a follow-up phone interview 10 days later.⁷ For management individuals, an internet survey was distributed via electronic mail, with 5 reminders, out there November 4, 2021, to June 30, 2022 (REDCap variations 10.6.9 and 12.0.13). The survey contained the identical “multiple choice” questions beforehand requested to sufferers, barely modified to the survey format.⁷ Informed consent was signed digitally. Prior to make use of, the online survey was evaluated for relevance and ease by a bunch of swimmers and researchers. In addition, 43 sufferers with SIPE accomplished the online survey following the follow-up interviews, enabling comparisons of responses (e-Table 1).¹⁹

Comorbidities of hypertension, bronchial asthma, and coronary heart illness have been self-reported doctor diagnoses, double-checked towards reported remedy. The following questions have been used to evaluate swimming expertise, earlier respiratory signs, and respiratory tract an infection, respectively: “How many times have you practiced swimming in open water this year?” (Never, 1-2, 3-5, > 5 instances.) “Have you previously experienced breathing problems or coughing when swimming in open water?” (Yes, No, I’ve by no means swum in open water.) “Have you had a respiratory tract infection either during the swim event or within the 7 days preceding it?” (Yes, No, Do not bear in mind.)

Data for attrition evaluation for the management group have been supplied by the Vansbrosimningen workplace.

Data Analysis and Models

For a subgroup of circumstances (n = 43), p.c settlement and Cohen’s kappa have been used to evaluate settlement between solutions from interviews and the online survey (e-Table 1). For management individuals, attrition evaluation was carried out for nonresponders and responders of the online survey utilizing distinction in share and the χ² take a look at. Logistic regression was additionally carried out with weighted analyses to account for nonresponder components within the management group (intercourse, age, leisure/aggressive swimmer, distance, and velocity).

For baseline traits, steady information are introduced as imply ± SD or as medians with interquartile ranges, and categorical information are introduced as numbers with percentages. Univariable and multivariable logistic regression fashions have been used for danger issue evaluation, with SIPE prognosis as a dependent variable.

In the examine’s information evaluation plan, 2 multivariable logistic regression fashions have been established based mostly on literature, medical expertise, and analysis in keeping with directed acyclic graphs (e-Fig 1). The first mannequin, specializing in comorbidity and former swimming expertise, included intercourse, age group (18-30, 31-40, 41-50, 51-60, and ≥ 61 years), hypertension, coronary heart illness, bronchial asthma, and frequency of open water swimming throughout the present season (> 5 instances, 3-5 instances, 1-2 instances, and by no means).

The second mannequin additionally included variables for earlier respiratory signs throughout swimming and acute respiratory tract an infection (e-Fig 1, e-Table 1). The query relating to respiratory tract infections was added to the questionnaire in 2018; due to this fact, information have been lacking for 59 individuals included in 2017. Also, earlier respiratory signs throughout open water swimming could mirror prior SIPE occasions, probably related to different particular person danger components. For respiratory infections, overadjustment might pose a danger when assessing the impact of bronchial asthma. Comparison of the two regression fashions, based mostly on information from 2018 to 2024 utilizing the chance ratio, statistically favored the second mannequin (P < .0001). Areas underneath the curve have been 0.767 and 0.799 for the primary and second mannequin, respectively. Multicollinearity was assessed by utilizing an adjusted common variance inflation issue for each fashions, ensuing generally variance inflation issue values of 1.0 to 1.1 for all covariates.

For sensitivity analyses, the second mannequin was repeated with separate additions of top, use of dietary dietary supplements of fish oil/omega 3 fatty acids, earlier than swim warm-up (in water or partially in water), and self-reported psychological stress at begin (e-Table 1). These components have been analyzed individually, because the questions relating to fish oil/omega 3 fatty acid use and psychological stress have been thought of to require cautious interpretation in keeping with outcomes from settlement evaluation. Warm-up and physiological stress have been added to the survey beginning in 2018.

IBM SPSS Statistics for Windows 28.0.0.0 and 29.0.1.0 (IBM SPSS Statistics, IBM Corporation), R model 4.5.2 (R Foundation for Statistical Computing), and GraphPad Prism 10.4.0 (GraphPad Software) have been used for statistical evaluation and graphic presentation. A P worth < .05 was thought of important.

Results

In whole, 53,610 grownup people participated in Vansbrosimningen through the years 2017 to 2019 and 2022 to 2024 (Fig 1). Altogether, 264 circumstances of SIPE have been identified throughout this era, and of those, 258 distinctive sufferers have been included as circumstances within the examine.

Of 9,782 distinctive grownup individuals in 2019, the survey was emailed to 9,702 swimmers with an out there electronic mail handle (Fig 1). The response price was 26% (n = 2,566). After additional excluding people with a historical past of SIPE and/or those that didn’t begin the race, 2,117 distinctive individuals have been included as management individuals. Attrition evaluation for the online survey confirmed that responders have been extra typically feminine, of older age, and with longer swimming distance and better velocity, nonetheless with low relative distinction between teams (e-Table 2). Analyses with nonresponse weighting accounting for these components confirmed greater ORs for all age teams in contrast with the baseline group (age 18-30 years) in each regression fashions however didn’t general have an effect on the associations with end result (information not proven).

Participant Characteristics

Individuals identified with SIPE have been extra typically feminine and aged > 40 years (Table 1). Overall, individuals symbolize a wholesome inhabitants. However, a better share of sufferers with SIPE reported hypertension (11.2% vs 5.4%), coronary heart illness (4.7% vs 0.9%), and/or bronchial asthma (15.5% vs 8.8%) in contrast with the management individuals. BMI was comparable in each teams, and virtually none smoked tobacco.

Table 1.

Background Characteristics of Participants With SIPE and Control Participants

Characteristic	SIPE (n = 258)	Control Participants (n = 2,117)
Individual traits
Female intercourse	219 (85)	1,185 (56)^a
Age group		^b
18–30 y	16 (6.2)	356 (17)
31–40 y	38 (15)	423 (20)
41–50 y	92 (36)	611 (29)
51–60 y	73 (28)	561 (27)
≥ 61 y	39 (15)	158 (7.5)
BMI, kg/m²	24 (22-27)^b	24 (23-27)^c
Tobacco smoking	2 (0.8)	21 (1.0)^a
Comorbidities and dietary dietary supplements
Hypertension	29 (11)	114 (5.4)^d
Heart illness	12 (4.7)	19 (0.9)^a
Angina, percutaneous coronary intervention with stent/myocardial infarction	2 (0.8)	4 (0.2)
Arrhythmia^e	7 (2.7)	11 (0.5)
Other	5 (1.9)	2 (0.1)
Asthma	40 (16)	187 (8.8)^c
Swimming expertise and well being standing on the race
Frequency of open water swimming throughout the present season		^c
Never	69 (27)	349 (17)
1-2 instances	78 (30)	499 (24)
3-5 instances	61 (24)	510 (24)
> 5 instances	50 (19)	729 (34)
Previous respiratory signs throughout open water swimming	^b	^f
Yes	69 (27)	240 (11)
No	182 (71)	1,803 (85)
Registration as a leisure swimmer	256 (99)	2,066 (98)
Swimming distance, race time (min)
1,000 m	69 (48), 34 (31-43)	337 (16), 28 (26-32)
1,500 m	13 (9.1), 62 (49-73)	216 (10), 46 (42-51)
3,000 m	61 (43), 89 (80-105)	1,548 (74), 69 (59-79)
Acute respiratory tract an infection^g	20 (12)^a	27 (1.3)^h

Of the 258 sufferers with SIPE, peripheral oxygen saturation information have been out there for 255. Among these, 113 sufferers (44%) had an oxygen saturation ≤ 91%, 89 (35%) between 92% and 95%, and 53 (21%) ≥ 96%. Altogether, 19 sufferers (7%) with SIPE have been referred to the hospital in 2017 to 2024.

Sex, Age, Comorbidity, and Swimming Experience

Female intercourse, greater age, hypertension, coronary heart illness, bronchial asthma, and frequency of open water swimming throughout the present season have been all independently related to SIPE in logistic regression evaluation, as proven within the first mannequin (Fig 2A, Table 2). Higher age mirrored an rising danger of SIPE as much as the oldest age group (≥ 61 years) in contrast with the group aged 18 to twenty years. Although the general incidence of coronary heart illness was low among the many individuals, it was related to a excessive OR for SIPE. Practicing open water swimming previous to the race was protecting towards SIPE, with the very best danger noticed amongst people who had not swum in open water throughout the present season, with a stepwise decrease danger for individuals who had swum 1 to 2, 3 to five, and > 5 instances, respectively.

Figure 2.

A, B, Forest plot illustrating OR for components related to swimming-induced pulmonary edema in adjusted logistic regression from the primary mannequin (A) and the second mannequin (B). ^aFrequency of open water swimming throughout the present season. ^bRespiratory signs reported in prior open water swimming.

Table 2.

Logistic Regression Analysis of the Association of Sex, Age, Comorbidity With SIPE, and Frequency of Open Water Swimming (First Model)

Variable	Unadjusted Analysis		Adjusted Analysis
Variable	OR (95% CI)	P Value	OR (95% CI)	P Value
Sex^a
Male	1.0	…
Female	4.4 (3.1-6.2)	< .001	5.3 (3.6-7.7)	< .001
Age group^b
18-30 y	1.0	…
31-40 y	2.0 (1.1-3.6)	.024	2.2 (1.2-4.0)	.014
41-50 y	3.4 (2.0-5.8)	< .001	4.2 (2.4-7.4)	< .001
51-60 y	2.9 (1.7-5.1)	< .001	4.0 (2.2-7.2)	< .001
≥ 61 y	5.5 (3.0-10.1)	< .001	7.3 (3.8-14.2)	< .001
Hypertension	2.2 (1.4-3.3)	<.001	1.9 (1.2-3.2)	.009
Heart illness	5.3 (2.6-11.1)	< .001	6.0 (2.5-14.2)	< .001
Asthma	1.9 (1.3-2.7)	< .001	1.7 (1.2-2.6)	.007
Frequency of open water swimming throughout the present season^c
> 5 instances	1.0	…
3-5 instances	1.7 (1.2-2.6)	.005	1.8 (1.2-2.6)	.007
1-2 instances	2.3 (1.6-3.3)	< .001	2.6 (1.7-3.8)	< .001
Never	2.9 (2.0-4.3)	< .001	3.6 (2.4-5.4)	< .001

Previous Respiratory Symptoms and Acute Respiratory Tract Infection

The second logistic regression mannequin additionally included the next: earlier respiratory signs throughout open water swimming and acute respiratory tract an infection (Fig 2B, Table 3). Both these components have been considerably related to SIPE, with the very best danger noticed in individuals who had an acute respiratory tract an infection on the time of the race (OR, 10.2; 95% CI, 5.2-20.2).

Table 3.

Logistic Regression Analysis of the Association Between SIPE and Sex, Age, Comorbidity, Frequency of Open Water Swimming, Previous Respiratory Symptoms During Open Water Swimming, and Acute Respiratory Tract Infection (Second Model Based on Cases 2018-2024)

Variable	Unadjusted Analysis		Adjusted Analysis: Second Model
Variable	OR (95% CI)	P Value	OR (95% CI)	P Value
Sex^a
Male	1.0	…
Female	4.4 (3.1-6.2)	< .001	4.7 (3.0-7.2)	< .001
Age group^b
18-30 y	1.0	…
31-40 y	2.0 (1.1-3.6)	.024	2.0 (0.9-4.1)	.078
41-50 y	3.4 (2.0-5.8)	< .001	4.0 (2.0-7.9)	< .001
51-60 y	2.9 (1.7-5.1)	< .001	4.0 (2.0-8.2)	< .001
≥ 61 y	5.5 (3.0-10.1)	< .001	6.7 (3.0-14.7)	< .001
Hypertension	2.2 (1.4-3.3)	< .001	1.9 (1.0-3.3)	.039
Heart illness	5.3 (2.6-11.1)	< .001	4.5 (1.6-12.8)	.006
Asthma	1.9 (1.3-2.7)	< .001	1.1 (0.7-1.9)	.649
Frequency of open water swimming throughout the present season^c
> 5 instances	1.0	…
3-5 instances	1.7 (1.2-2.6)	.005	1.9 (1.2-3.1)	.011
1-2 instances	2.3 (1.6-3.3)	< .001	2.9 (1.8-4.7)	< .001
Never	2.9 (2.0-4.3)	< .001	4.2 (2.5-7.0)	< .001
Previous respiratory signs throughout open water swimming	2.8 (2.1-3.9)	< .001	3.5 (2.3-5.2)	< .001
Acute respiratory tract an infection^d	9.0 (5.0-16.5)	<.001	10.2 (5.2-20.2)	< .001

When these components have been included within the mannequin, bronchial asthma was not an unbiased danger issue for SIPE (Fig 2B, Table 3), even when earlier respiratory signs throughout open water swimming or acute respiratory tract an infection have been added individually (information not proven).

Other Factors and Sensitivity Analyses

We selected to guage a number of further danger components of curiosity by unadjusted logistic regression in addition to including them individually to the second regression mannequin. Shorter top was related to SIPE in unadjusted evaluation however not when added to the adjusted mannequin (e-Table 3). Use of dietary dietary supplements of fish oil/omega 3 fatty acids, warming up in water earlier than the swim, and reporting psychological stress at begin have been additionally evaluated. None of those components was related to SIPE in univariate evaluation or within the adjusted mannequin (second mannequin). The use of a wetsuit was not evaluated as nearly all swimmers used wetsuits; 97.7% in sufferers with SIPE and 97.3% in management individuals.

Discussion

The identification of danger components for SIPE requires large-scale research, which is difficult for a situation with a low incidence. We carried out a case-control examine based mostly on Sweden’s largest open water swimming occasion. Previously reported danger components for SIPE and IPE, together with feminine intercourse, older age, hypertension, coronary heart illness, respiratory an infection, and prior episodes of SIPE, have been discovered to be independently related to the prevalence of SIPE. We additional recognized 2 potential danger components not beforehand reported in affiliation with SIPE: bronchial asthma and restricted expertise of open water swimming.

The inhabitants collaborating in Vansbrosimningen is general wholesome. We beforehand introduced hypertension and bronchial asthma as the commonest comorbidities in sufferers with SIPE.⁷ In the present examine, which included a management group of swimmers from the identical occasion, hypertension was related to SIPE prognosis along with reported coronary heart illness. In 1989, Wilmshurst et al⁵ described improvement of hypertension in a bunch of scuba divers and swimmers with IPE. Hypertension has additionally been reported in each swimmers and divers with SIPE/IPE.⁹^,¹⁰^,¹²^,²⁰ Hypertension is a widely known danger issue for left ventricular hypertrophy and decreased left ventricular compliance, which can contribute to elevated pulmonary capillary stress throughout exertion.⁹ Left ventricular hypertrophy has been hypothesized as a marker for SIPE susceptibility in triathletes who died throughout swimming.²¹ Hypertension can also be a recognized danger issue for atrial fibrillation. Of 12 sufferers with SIPE reporting coronary heart illness within the present examine, 6 reported atrial fibrillation. The sturdy affiliation noticed between coronary heart illness and SIPE in these information is according to earlier findings in middle-aged divers with IPE.¹⁰^,¹¹^,²⁰ Studies specializing in underlying cardiac perform and dysfunction can be helpful to additional make clear the pathophysiology of SIPE and discover the associations with feminine intercourse, older age, hypertension, and coronary heart illness.

In a earlier follow-up examine, we reported an affiliation between bronchial asthma and longer symptom period throughout SIPE, in addition to an elevated danger of recurrence.⁷ In the present examine, bronchial asthma was independently related to SIPE within the first regression mannequin. However, this affiliation didn’t persist following adjustment for both beforehand reported respiratory signs throughout open water swimming or the presence of an acute respiratory tract an infection. Adjusting for these 2 variables carries a possible danger of overadjustment. If beforehand reported respiratory signs whereas swimming in open water represents true SIPE occasions, adjusting for them could account for the general individual-level danger for SIPE. For people with bronchial asthma, respiratory signs throughout bodily exercise in chilly water could mirror asthma-related signs. Moreover, bronchial asthma could exacerbate the severity and period of signs throughout a respiratory an infection, by which case the an infection could act as a mediator between bronchial asthma and SIPE. A prevalence of self-reported bronchial asthma of 12% was discovered amongst individuals of three Swedish endurance occasions, together with Vansbrosimningen.²² In the present examine, 16% of sufferers with SIPE and 9% of management individuals reported bronchial asthma, in contrast with 7% to 11% reported for the middle-aged Swedish inhabitants.²³^,²⁴ To our information, there aren’t any earlier experiences of an affiliation between bronchial asthma and creating SIPE/IPE; it will thus be attention-grabbing to confirm our findings in different cohorts.

As talked about earlier, each acute respiratory tract an infection and former respiratory signs throughout open water swimming (suggestive of prior SIPE) have been independently related to an elevated danger of SIPE. Respiratory tract an infection as a danger issue for SIPE is according to information from the Navy Sea, Air, and Land (SEAL) candidates, 62% of whom reported previous respiratory an infection signs.¹³ In abstract, we will speculate that each bronchial asthma and respiratory infections improve vulnerability within the small airways and should facilitate the event of pulmonary edema.²⁵ Local irritation compromises the integrity of the alveolar-capillary barrier, making it extra prone to hydrostatic stress throughout train and immersion.²⁶ These information collectively emphasize that people with an ongoing respiratory an infection have a better danger for SIPE and that open water swimming needs to be averted throughout respiratory an infection. Although bronchial asthma as a possible danger issue for SIPE warrants additional investigation, it’s already essential to emphasise affected person schooling relating to the acute signs of SIPE, notably amongst open water swimmers with bronchial asthma.

Studies in leisure swimmers are missing, as most research of SIPE are revealed amongst well-trained militaries and triathletes. Interestingly, the low frequency of open water swimming throughout the present season turned out to be a danger issue for SIPE. In addition to elevated consolation with the open water swimming atmosphere, leading to decreased psychological stress throughout the race, we consider that frequent open water apply displays a better general degree of swimming expertise. Less skilled swimmers exhibit greater oxygen uptake, indicating a larger degree of exertion, in contrast with elite swimmers on the similar swimming velocity.²⁷ Strenuous exertion has been proposed as a contributing issue concerned within the improvement of IPE.¹¹^,¹² In reality, sufferers identified with SIPE within the present cohort swam at slower speeds and have been registered for shorter distances in contrast with the management individuals. However, each information are tough to interpret, because the time within the water could also be influenced by experiencing SIPE throughout the race, and management individuals who participated in a number of races have been instructed to report the longest race within the internet survey.

To account for the potential affect of psychological stress, we included “self-reported stress at start” and “in-water warm-up” within the present sensitivity analyses. Psychological stress could be an attention-grabbing issue for SIPE as it will probably trigger, for instance, elevated sympathetic drive, redistributed blood quantity, and modifications in respiratory patterns.²⁸ All of those mechanisms might also be essential for SIPE, and psychological stress has been reported in divers with IPE.¹¹ Because self-reported psychological stress throughout the race might be affected by SIPE (eg, signs of shortness of breath), we solely included stress reported firstly of the evaluation. Neither of those components finally was considerably related to the prevalence of SIPE within the present information.

Because smaller lung volumes have been advised beforehand to be related to SIPE,⁴ we added top to the second mannequin as an oblique measurement for lung capability. Height was considerably related to SIPE in univariate evaluation, though not within the adjusted mannequin, and it didn’t have an effect on the opposite outcomes. These findings recommend that components aside from top and lung volumes could clarify the affiliation between feminine intercourse, older age, and SIPE. Because Miller et al⁹ surprisingly discovered that SIPE was related to using fish oil, we have been all in favour of exploring this issue. We couldn’t verify an affiliation between utilizing dietary dietary supplements of fish oil/omega-3 fatty acids and the prevalence of SIPE.

One power of this examine is that the unique cohort of Vansbrosimningen consisted of a giant and heterogeneous inhabitants, which boosts the generalizability of the findings. Another power is the low variety of SIPE circumstances misplaced to follow-up, in addition to using telephone-based interviews for assortment of information for sufferers with SIPE. As for limitations, using a web-based survey for management individuals represents a limitation, though this was tough to keep away from. To handle this, we carried out an settlement evaluation evaluating responses from phone interviews vs these obtained from the web-based questionnaire previous to its implementation. To reduce self-reporting bias relating to earlier illnesses, we requested physician-confirmed medical diagnoses and in contrast the responses with reported drugs. The management group was drawn solely from swimmers in 2019 and regardless of equal incidence of SIPE in addition to comorbidity within the affected person group throughout the years, a temporal confounding can’t be excluded. The response price of 26% for the online survey is akin to different comparable research.²²^,²⁹ As suspected, attrition evaluation indicated choice bias, with feminine intercourse and older age overrepresented among the many management individuals, though danger estimates remained constant in weighted regression analyses.³⁰

Interpretation

Consistent with a number of research to this point, the present information present that feminine intercourse, greater age, and hypertension are related to an elevated danger of SIPE. Heart illness, though reported by just a few of the in any other case wholesome open water swimmers, was discovered to be strongly related to SIPE. Asthma emerged within the present examine as a possible danger issue for SIPE, together with ongoing respiratory an infection. A compromised alveolar-capillary barrier because of native irritation could represent a believable shared mechanism. Interestingly, partaking in open water swimming previous to the race appeared to be a protecting issue towards SIPE. Whether this impact displays a discount in psychological stress and sympathetic activation or just serves as a proxy for higher swimming approach and expertise, can’t be decided based mostly on our present information. Awareness of danger components for SIPE is essential for particular person swimmers, in addition to organizers of open water swimming occasions and well being care suppliers.

Funding/Support

Financial help was supplied by the Center for Research and Development, Uppsala University/Region Gävleborg (CFUG), and the Center for Clinical Research (CKF) Dalarna-Uppsala University.

Financial/Nonfinancial Disclosures

None declared.

Acknowledgments

Author contributions: L. Okay. takes accountability for the content material of the manuscript, together with information and evaluation. L. Okay., M. H., and J. S. initiated the examine. L. Okay. carried out the info evaluation and wrote the primary draft of the manuscript, with assist from M. H. and J. S. All authors took energetic half in examine design, logistics, information assortment and interpretation of the info, and important revision of the manuscript. All authors reviewed and permitted the ultimate manuscript.

Role of sponsors: The sponsor had no function within the design of the examine, the gathering and evaluation of the info, or the preparation of the manuscript.

Other contributions: The authors thank all swimmers who’ve participated within the interviews and/or responded to the survey and all who gave enter on the varieties and survey (ie, Dag Rissén, PhD). They additionally thank personnel throughout Vansbrosimningen, specifically Daniel Lundequist for assist with interviews and Tomas Viker on the Vansbrosimningen workplace, statistical assist (Riccardo Lomartire, Kristoffer Sehlberg), and help with REDCap (ie, Gustav Svensk).

Declaration of generative AI and AI-assisted applied sciences within the writing course of: During the preparation of this work the authors used ChatGPT with the intention to help with language enhancing of particular person sentences. After utilizing this device, the authors reviewed and edited the content material as wanted and takes full accountability for the content material of the publication.

Additional data: The e-Figure and e-Tables can be found on-line underneath “Supplementary Data.”

Supplementary Data

e-Online Data

References

1.Banham N., Smart D., Wilmshurst P., Mitchell S.J., Turner M.S., Bryson P. Joint place assertion on immersion pulmonary oedema and diving from the South Pacific Underwater Medicine Society (SPUMS) and the United Kingdom Diving Medical Committee (UKDMC) 2024. Diving Hyperb Med. 2024;54(4):344–349. doi: 10.28920/dhm54.4.344-349. [DOI] [PMC free article] [PubMed] [Google Scholar]
2.Grunig H., Nikolaidis P.T., Moon R.E., Knechtle B. Diagnosis of swimming induced pulmonary edema—a evaluate. Front Physiol. 2017;8:652. doi: 10.3389/fphys.2017.00652. [DOI] [PMC free article] [PubMed] [Google Scholar]
3.Weiler-Ravell D., Shupak A., Goldenberg I., et al. Pulmonary oedema and haemoptysis induced by strenuous swimming. BMJ. 1995;311(7001):361–362. doi: 10.1136/bmj.311.7001.361. [DOI] [PMC free article] [PubMed] [Google Scholar]
4.Shupak A., Weiler-Ravell D., Adir Y., Daskalovic Y.I., Ramon Y., Kerem D. Pulmonary oedema induced by strenuous swimming: a subject examine. Respir Physiol. 2000;121(1):25–31. doi: 10.1016/s0034-5687(00)00109-2. [DOI] [PubMed] [Google Scholar]
5.Wilmshurst P.T., Nuri M., Crowther A., Webb-Peploe M.M. Cold-induced pulmonary oedema in scuba divers and swimmers and subsequent improvement of hypertension. Lancet (London, England) 1989;1(8629):62–65. doi: 10.1016/s0140-6736(89)91426-8. [DOI] [PubMed] [Google Scholar]
6.Hårdstedt M., Kristiansson L., Seiler C., Braman Eriksson A., Sundh J. Incidence of swimming-induced pulmonary edema: a cohort examine based mostly on 47,600 open-water swimming distances. Chest. 2021;160(5):1789–1798. doi: 10.1016/j.chest.2021.06.034. [DOI] [PMC free article] [PubMed] [Google Scholar]
7.Kristiansson L., Seiler C., Lundeqvist D., Braman Eriksson A., Sundh J., Hårdstedt M. Symptom period, recurrence, and long-term results of swimming-induced pulmonary edema: a 30-month follow-up examine. Chest. 2023;164(5):1257–1267. doi: 10.1016/j.chest.2023.06.041. [DOI] [PMC free article] [PubMed] [Google Scholar]
8.Coulange M., Rossi P., Gargne O., et al. Pulmonary oedema in wholesome SCUBA divers: new physiopathological pathways. Clin Physiol Funct Imaging. 2010;30(3):181–186. doi: 10.1111/j.1475-097X.2010.00922.x. [DOI] [PubMed] [Google Scholar]
9.Miller C.C., third, Calder-Becker Okay., Modave F. Swimming-induced pulmonary edema in triathletes. Am J Emerg Med. 2010;28(8):941–946. doi: 10.1016/j.ajem.2009.08.004. [DOI] [PubMed] [Google Scholar]
10.Peacher D.F., Martina S.D., Otteni C.E., Wester T.E., Potter J.F., Moon R.E. Immersion pulmonary edema and comorbidities: case sequence and up to date evaluate. Med Sci Sports Exerc. 2015;47(6):1128–1134. doi: 10.1249/MSS.0000000000000524. [DOI] [PubMed] [Google Scholar]
11.Edmonds C., Lippmann J., Bove A. Immersion pulmonary edema: an evaluation of 31 circumstances from Oceania. Undersea Hyperb Med. 2019;46(5):603–610. [PubMed] [Google Scholar]
12.Henckes A., Cochard G., Gatineau F., et al. Risk components for immersion pulmonary edema in leisure scuba divers: a case-control examine. Undersea Hyperb Med. 2019;46(5):611–618. [PubMed] [Google Scholar]
13.Sebreros B.A., Wisniewski P., Lindholm P., Boswell G.E., Volk C.G. Incidence of respiratory pathogens in Naval Special Warfare sea, air, and land staff candidates with swimming-induced pulmonary edema. Chest. 2023;163(5):1185–1192. doi: 10.1016/j.chest.2022.11.023. [DOI] [PubMed] [Google Scholar]
14.Hohmann E., Glatt V., Tetsworth Okay. Swimming induced pulmonary oedema in athletes—a scientific evaluate and finest proof synthesis. BMC Sports Sci Med Rehabil. 2018;10:18. doi: 10.1186/s13102-018-0107-3. [DOI] [PMC free article] [PubMed] [Google Scholar]
15.Marabotti C., Prediletto R., Scalzini A., et al. Cardiovascular and respiratory results of the neoprene wetsuit in non-immersed divers. Undersea Hyperb Med. 2017;44(2):141–147. doi: 10.22462/3.4.2017.7. [DOI] [PubMed] [Google Scholar]
16.Spencer S., Dickinson J., Forbes L. Occurrence, danger components, prognosis and prevention of swimming-induced pulmonary oedema: a scientific evaluate. Sports Med Open. 2018;4(1):43. doi: 10.1186/s40798-018-0158-8. [DOI] [PMC free article] [PubMed] [Google Scholar]
17.Seiler C., Kristiansson L., Klingberg C., et al. Swimming-induced pulmonary edema: analysis of prehospital therapy with CPAP or optimistic expiratory stress gadget. Chest. 2022;162(2):410–420. doi: 10.1016/j.chest.2022.02.054. [DOI] [PMC free article] [PubMed] [Google Scholar]
18.Hårdstedt M., Seiler C., Kristiansson L., Lundeqvist D., Klingberg C., Braman Eriksson A. Swimming-induced pulmonary edema: diagnostic standards validated by lung ultrasound. Chest. 2020;158(4):1586–1595. doi: 10.1016/j.chest.2020.04.028. [DOI] [PubMed] [Google Scholar]
19.Landis J.R., Koch G.G. The measurement of observer settlement for categorical information. Biometrics. 1977;33(1):159–174. [PubMed] [Google Scholar]
20.Wilmshurst P.T. Immersion pulmonary oedema: a cardiological perspective. Diving Hyperb Med. 2019;49(1):30–40. doi: 10.28920/dhm49.1.30-40. [DOI] [PMC free article] [PubMed] [Google Scholar]
21.Moon R.E., Martina S.D., Peacher D.F., Kraus W.E. Deaths in triathletes: immersion pulmonary oedema as a potential trigger. BMJ Open Sport Exerc Med. 2016;2(1) doi: 10.1136/bmjsem-2016-000146. [DOI] [PMC free article] [PubMed] [Google Scholar]
22.Näsman A., Irewall T., Hållmarker U., Lindberg A., Stenfors N. Asthma and bronchial asthma remedy are widespread amongst leisure athletes collaborating in endurance sport competitions. Can Respir J. 2018;2018 doi: 10.1155/2018/3238546. [DOI] [PMC free article] [PubMed] [Google Scholar]
23.Backman H., Hedman L., Jansson S.A., Lindberg A., Lundbäck B., Rönmark E. Prevalence tendencies in respiratory signs and bronchial asthma in relation to smoking—two cross-sectional research ten years aside amongst adults in northern Sweden. World Allergy Organ J. 2014;7(1):1. doi: 10.1186/1939-4551-7-1. [DOI] [PMC free article] [PubMed] [Google Scholar]
24.Lötvall J., Ekerljung L., Rönmark E.P., et al. West Sweden Asthma Study: prevalence tendencies over the past 18 years argues no current improve in bronchial asthma. Respir Res. 2009;10(1):94. doi: 10.1186/1465-9921-10-94. [DOI] [PMC free article] [PubMed] [Google Scholar]
25.Bove A.A. Pulmonary features of train and sports activities. Methodist Debakey Cardiovasc J. 2016;12(2):93–97. doi: 10.14797/mdcj-12-2-93. [DOI] [PMC free article] [PubMed] [Google Scholar]
26.Hårdstedt M., Seiler C. Swimming-induced pulmonary edema: respiratory pathogens as a possible danger issue. Chest. 2023;163(5):1009–1010. doi: 10.1016/j.chest.2023.01.001. [DOI] [PubMed] [Google Scholar]
27.Holmér I. Swimming physiology. Ann Physiol Anthropol. 1992;11(3):269–276. [PubMed] [Google Scholar]
28.Chu B., Marwaha Okay., Sanvictores T., Awosika A.O., Ayers D. StatPearls Publishing LLC; 2025. Physiology, Stress Reaction. [PubMed] [Google Scholar]
29.Braekman E., Demarest S., Charafeddine R., et al. Unit response and prices in internet versus face-to-face information assortment: comparability of two cross-sectional well being surveys. J Med Internet Res. 2022;24(1) doi: 10.2196/26299. [DOI] [PMC free article] [PubMed] [Google Scholar]
30.Mölenberg F.J.M., de Vries C., Burdorf A., van Lenthe F.J. A framework for exploring non-response patterns over time in well being surveys. BMC Med Res Methodol. 2021;21(1):37. doi: 10.1186/s12874-021-01221-0. [DOI] [PMC free article] [PubMed] [Google Scholar]

Associated Data

This part collects any information citations, information availability statements, or supplementary supplies included on this article.

Supplementary Materials

e-Online Data

This web page was created programmatically, to learn the article in its authentic location you may go to the hyperlink bellow:
https://pmc.ncbi.nlm.nih.gov/articles/PMC13494432/
and if you wish to take away this text from our website please contact us

fooshya