Association between gardening and the risk of atrial fibrillation in patients at the outpatient cardiology clinic

Abstract

Objectives: Exercise therapy targets modifiable risk factors and reportedly prevents atrial fibrillation (AF). Gardening is a form of regular exercise that provides mental benefits. Thus, we hypothesized that gardening might be associated with a lower incidence of AF. Herein, we aimed to evaluate the association between gardening and the risk of AF onset.

Methods: Between August 2022 and March 2023, we surveyed 783 patients at risk of heart failure (HF) without a history of AF or HF-related hospitalization at a cardiology outpatient clinic (median patient age 73 years; 63% male). Gardening was defined as cultivating flowers, vegetables, or fruits for over a year. The presence, frequency, duration, years of experience, and scale were assessed. AF risk was estimated using the Cohorts for Heart and Aging in Genomic Epidemiology–Atrial Fibrillation (CHARGE-AF) score and categorized into tertiles. The association between gardening and CHARGE-AF score was analyzed using ordinal logistic regression, adjusted for confounders.

Results: Approximately 69% of the patients were engaged in gardening. Furthermore, 31%, 29%, and 40% of the patients had low-risk, medium-risk, and high-risk CHARGE-AF scores, respectively. Gardening was inversely associated with CHARGE-AF score (odds ratio = 0.532, 95% confidence intervals [0.304–0.924]). Gardening extent demonstrated a trend towards lower AF risk, with significant associations only for years of experience.

Conclusion: Gardening may be associated with a lower risk of AF in patients at the outpatient cardiology clinic.

 Introduction

Atrial fibrillation (AF) is a frequently encountered arrhythmia in routine clinical practice¹⁾. It is associated with a diminished quality of life due to symptoms, such as palpitations and dyspnea, and an increased risk of cardiovascular adverse events, such as stroke, myocardial infarction, heart failure, and mortality¹⁾. According to the guidelines of the Japanese Circulation Society, interventions targeting modifiable risk factors, such as hypertension, diabetes, and obesity, are crucial for preventing the onset of AF^2,3).

Exercise therapy, including cardiac rehabilitation, is effective in reducing modifiable risk factors, and it could suppress the onset of AF³⁾. However, the widespread implementation of outpatient comprehensive cardiac rehabilitation remains limited. Thus, exercise prescriptions often only cover activities such as walking or resistance training.

Gardening is a common hobby in daily life that typically involves physical activity levels of 2 to 8 Metabolic Equivalents (METs)⁴⁾. Furthermore, gardening reportedly alleviates psychological symptoms such as stress, depression, and anxiety and is a recognized form of occupational or horticultural therapy in psychiatry^5,6). The onset of AF is reportedly influenced by psychological status and the autonomic nervous system^7–9). Thus, we hypothesized that gardening, with its physical and psychological benefits, could lower the risk of AF development. In this study, we aimed to investigate the association between gardening and the risk of AF onset.

 Materials and Methods

 Study population

This cross-sectional study was carried out in Ozu City, Ehime Prefecture, Japan. As of March 31, 2023, the population of Ozu City was 40,255. In 2020, compared to the national average of 3.2%, 11.4% of the city’s workforce was employed in the primary industry sector^10,11).

We conducted a questionnaire-based survey, obtained physical measurements, and performed routine examinations, including blood tests and echocardiograms, in 1,569 patients who regularly visited our outpatient cardiology clinic between August 2022 and March 2023. Of the 1,569 patients, 1,277 (81%) responded to the survey and consented to participate in the study. Patients with symptomatic heart failure (n = 267) or a history of AF, including paroxysmal AF (n = 227), were excluded from the study. Finally, 783 patients who were at risk for heart failure and had no history of AF were included in the study (Fig. 1). This study was conducted according to the Declaration of Helsinki and approved by the ethics committee of the Ehime University Graduate School of Medicine (No: 2208004; date: 2022/08/08).

Fig. 1.  Flow diagram of the study population

 Data related to gardening

We defined gardening as “the cultivation of flowers, vegetables, and fruit,” and gardening activity as “engagement in gardening for a minimum of one year”¹²⁾. The survey included questions regarding the presence and frequency of gardening, duration per session, and years of experience. To further characterize gardening activity, it was categorized based on the level of physical activity (METs) and environmental setting as follows: (1) using planters at home, corresponding to low-intensity physical activity (<3 METs); (2) home gardening (e.g., backyard or balcony), corresponding to low- to moderate-intensity physical activity (approximately 3 METs); (3) non-commercial gardening outside the home (e.g., community gardens), corresponding to moderate-intensity physical activity (3–6 METs); and (4) commercial gardening outside the home (e.g., farming for income or large-scale production), corresponding to high-intensity physical activity (>6 METs)⁴⁾. According to cardiac rehabilitation recommendations for patients with heart failure³⁾, gardening frequency was classified as <4 times/week or ≥4 times/week. The duration of gardening sessions was classified as <30 min or ≥30 min. The years of experience were divided into tertiles.

 Other data collected via the survey

Lifestyle factors such as smoking status and exercise habits (defined as at least 30 min of physical activity twice a week for >1 year) were recorded¹³⁾. Additionally, we assessed psychological metrics using the Patient Health Questionnaire-2 (PHQ-2)¹⁴⁾, Generalized Anxiety Disorder-7 (GAD-7) scale¹⁵⁾, and Cantril’s Ladder of Life scale (an 11-point scale that assesses current life satisfaction)¹⁶⁾.

 Data extracted from medical records

The following data were collected from patients’ clinical records: demographics, physical measurements, comorbidities, medication history, blood test results, and echocardiogram findings. Additionally, we determined the main cause of cardiac dysfunction in patients with Stage B heart failure.

Smoking status was classified based on self-reported responses to a structured questionnaire. Participants who reported never having smoked were defined as never smokers. Current smokers were defined as those who self-reported continuing to smoke at the time of the survey. Grip strength was measured twice on each hand alternately using a hand dynamometer. The final grip strength value was calculated as the average of the higher values recorded from the right and left hands¹⁷⁾. Hypertension was defined as a systolic blood pressure ≥140 mmHg, diastolic blood pressure ≥90 mmHg, or current use of antihypertensive medication¹⁸⁾. Dyslipidemia was defined as a low-density lipoprotein (LDL) cholesterol level ≥140 mg/dL, a high-density lipoprotein (HDL) cholesterol level <40 mg/dL, a triglyceride level ≥150 mg/dL, or current use of lipid-lowering medication¹⁹⁾. Diabetes mellitus was defined as a fasting plasma glucose level ≥126 mg/dL, a hemoglobin A1c (HbA1c) level ≥6.5%, or current use of antidiabetic medications²⁰⁾.

 Outcome

The Cohorts for Heart and Aging in Genomic Epidemiology–Atrial Fibrillation (CHARGE-AF) score was selected as the outcome variable²¹⁾.This score, which is expressed as a percentage, predicts the 5-year risk of AF onset. Furthermore, higher CHARGE-AF scores indicate a higher risk of AF onset. In the present study, we used a simple scoring model composed of age, race, height, weight, systolic blood pressure, diastolic blood pressure, smoking status, antiplatelet medication use, diabetes, history of heart failure, and history of myocardial infarction. The calculated scores (risk of AF onset) were categorized into low (<2.5%), moderate (2.5%–5%), and high (>5%)²¹⁾.

 Statistical analysis

Study variables between patients engaged and those not engaged in gardening were compared using the Mann–Whitney U, Fisher’s exact, or Chi-squared test, according to the parameter type or distribution. We selected covariates based on previously established risk factors for AF onset and further incorporated psychological metrics^1,22). The variables were as follows: age, sex, body mass index (BMI), heart rate, smoking status, grip strength, exercise habits, B-type natriuretic peptide (BNP) level, estimated glomerular filtration rate (eGFR), hemoglobin level, serum uric acid level, hypertension, chronic lung disease, sleep-disordered breathing, angiotensin-converting enzyme inhibitor use, angiotensin receptor blocker use, angiotensin receptor-neprilysin inhibitor use, beta-blocker use, PQ interval, E/e', left ventricular ejection fraction, left ventricular mass index, left atrial volume index, tricuspid pressure gradient, mitral regurgitation, controlling nutritional status score, frequency of vegetable dish intake, PHQ-2, GAD-7 score, and Cantril’s Ladder of Life score. The BNP values were log-transformed. Diabetes and a history of myocardial infarction were not included as covariates in the present analysis. Myocardial infarction is not listed as a modifiable risk factor for AF in the guidelines, and evidence supporting a clear association between diabetes and AF remains limited¹⁾. As both factors are components of the CHARGE-AF score, we did not include them as independent variables to avoid redundant adjustment.

We calculated the adjusted odds ratios (OR) and 95% confidence intervals (CI) for the association between gardening and its components and the categorical CHARGE-AF scores. Furthermore, we assessed the trends in these associations using multiple ordinal logistic regression analysis. All analyses were based on complete cases, without imputation for missing values. As a result, the number of patients varied across models depending on data availability.

Additionally, as a supplementary analysis, baseline characteristics including gardening activity were compared between patients with and without known atrial fibrillation using the Mann–Whitney U and Chi-squared tests.

Statistical significance was set at p < 0.05. Statistical analysis was carried out using EZR (version 1.52; Saitama Medical Center Jichi Medical University, Saitama, Japan ) with extended R and R Commander functions²³⁾.

 Results

The median (interquartile range) age of the patients was 73 (66–79) years. Approximately 64% of the respondents were male. Among the patients with Stage B heart failure, the majority had ischemic heart disease as the primary pathology (61%), followed by valvular heart diseases (11%). The median interval between questionnaire completion and performance of routine examination was 17 days.

Approximately 69% of the patients reported engaging in gardening. The gardening group had a significantly higher average age, lower proportion of males, and higher prevalence of regular exercise habits than the non-gardening group (Table 1). In addition, several parameters in the physiologic measures, laboratory measures, comorbidities, treatment, and echocardiographic measures categories showed significant variations between the gardening group and the non-gardening group. Furthermore, in the psychological measures, the gardening group showed significantly better results in PHQ-2 and Cantril’s Ladder of Life compared to the non-gardening group.

Table 1.Patient characteristics in the study population

Parameters		Number of observations	Non-gardening group (n = 240)	Gardening group (n = 543)	p
Age (years)		783	69.0 (61.0–77.0)	74.0 (68.5–80.0)	<0.001
Male, n (%)		783	177 (73.8)	321 (59.1)	<0.001
Heart failure stage, n (%)	A	783	69 (28.7)	171 (31.5)	0.451
	B		171 (71.2)	372 (68.5)
Exercise habits, n (%)		777	109 (45.6)	307 (57.1)	0.004
Current smoking status, n (%)		783	27 (11.2)	42 (7.7)	0.132
Physiologic measures
Grip strength (kg)		782	29.6 (22.4–36.7)	27.1 (21.4–34.7)	0.010
Body mass index (kg/m2)		783	24.9 (22.34–28.0)	23. 9 (21.6–26.4)	0.001
Heart rate (/min)		783	72 (65–81)	71 (65–78)	0.055
Systolic blood pressure (mmHg)		783	138 (128–148)	139 (127–150)	0.727
Diastolic blood pressure (mmHg)		783	77 (69–85)	74 (66–81)	<0.001
NYHA classification, n (%)	I	783	168 (70.0)	366 (67.4)	0.002
	II		60 (25.0)	171 (31.5)
	III		12 (5.0)	6 (1.1)
	IV		0	0
CONUT score		783	1 (1–2)	1 (0–2)	0.249
Laboratory measures
BNP (pg/mL)		782	17.0 (8.0–39.0)	25.2 (12.0–45.0)	<0.001
eGFR (mL/min/1.73 m2)		783	61.0 (51.0–71.0)	59.0 (48.0–68.5)	0.027
Hemoglobin (g/dL)		783	13.9 (12.6–15.0)	13.3 (12.1–14.4)	<0.001
Comorbidities
Myocardial infarction, n (%)		783	71 (29.6)	111 (20.4)	0.006
Diabetes, n (%)		783	80 (33.3)	161 (29.7)	0.314
Hypertension, n (%)		783	199 (82.9)	423 (77.9)	0.125
Dyslipidemia, n (%)		783	152 (63.3)	349 (64.3)	0.809
COPD, n (%)		783	28 (11.7)	64 (11.8)	1.000
Stroke, n (%)		783	23 (9.6)	46 (8.5)	0.682
Sleep disordered breathing, n (%)		783	14 (5.8)	26 (4.8)	0.598
Treatment
ACEI/ARB/ARNI, n (%)		783	149 (62.1)	299 (55.1)	0.072
Beta-blocker, n (%)		783	144 (60.0)	269 (49.5)	0.008
MRA, n (%)		783	34 (14.2)	62 (11.4)	0.289
SGLT2i, n (%)		783	45 (18.8)	66 (12.2)	0.019
Electrocardiographic measures
PQ (ms)		781	176 (162.0–194.0)	176 (162.0–198.0)	0.791
Echocardiographic measures
Left ventricular ejection fraction (%)		773	62.0 (57.0–66.0)	64.0 (59.0–67.0)	0.003
Left ventricular mass index (ml/m2)		783	115.6 (100.1–133.5)	118.1 (100.4–136.1)	0.317
Left atrial volume index (ml/m2)		783	35.1 (28.3–41.9)	37.0 (29.9–45.3)	0.003
E/e'		773	10.8 (9.07–13.8)	11.6 (9.3–14.5)	0.107
TRPG		773	19.5 (15.0–22.0)	20.0 (17.0–24.0)	0.004
Psychological measures
PHQ-2		734	0 (0–2)	0 (0–2)	0.048
GAD-7		757	1 (0–5)	1 (0–5)	0.269
Cantril’s Ladder of Life*		729	7 (5–8)	8 (6–9)	<0.001

Data are expressed as median (interquartile range) or number (%)

*Cantril’s Ladder of Life was evaluated on an 11-point scale from 0 to 10 for current life satisfaction.

ACEi: angiotensin-converting enzyme inhibitors, ARB: angiotensin receptor blockers, ARNI: angiotensin receptor-neprilysin inhibitor, BNP: B-type natriuretic peptide, CONUT: controlling nutritional status, eGFR: estimated glomerular filtration rate, COPD: chronic obstructive pulmonary disease, TRPG: tricuspid regurgitation pressure gradient, GAD-7: Generalized Anxiety Disorder 7-item scale, MRA: mineralocorticoid receptor antagonist, NYHA: New York Heart Association, PHQ-2: Patient Health Questionnaire-2, SGLT2i: sodium-glucose cotransporter-2 inhibitor.

 Outcome

The mean CHARGE-AF score was 5.7% ± 5.7%, and the median CHARGE-AF score was 3.9 (2.1–7.3) %. Of the 783 included patients, 240 (31%) had a low-risk CHARGE-AF score, 225 (29%) had a medium-risk score, and 318 (40%) had a high-risk score (Supplemental Fig. 1).

 Association between gardening and CHARGE-AF score

The association between gardening and CHARGE-AF score was evaluated using three models (Table 2). Model 1, which was adjusted for age and sex, revealed an inverse association between gardening and CHARGE-AF score. Model 2, which was adjusted for age, sex, and various physical and clinical markers, demonstrated a significant inverse association between gardening and CHARGE-AF score. Model 3, which was adjusted for psychological indices in addition to the variable in Model 2, also demonstrated an inverse association between gardening and CHARGE-AF score.

Table 2.Association between gardening and CHARGE-AF score using three different models

Model		Adjusted OR (95% CI)
Model 1a (n = 783)
Gardening activity	No	1
	Yes	0.530 (0.343–0.813)
Model 2b (n = 765)
Gardening activity	No	1
	Yes	0.548 (0.329–0.906)
Model 3c (n = 677)
Gardening activity	No	1
	Yes	0.532 (0.304–0.924)

^a Adjustment for age and sex

^b Model 1+ Adjustment for exercise habits, smoking, grip strength, body mass index, heart rate, ln(B-type natriuretic peptide), estimated glomerular filtration rate, hemoglobin level, uric acid level, hypertension, chronic lung disease, sleep-disordered breathing, angiotensin-converting enzyme inhibitors/angiotensin receptor blockers/angiotensin receptor-neprilysin inhibitor, beta-blocker, PQ interval, left ventricle ejection fraction, left ventricular mass index, left atrial volume index, E/e', tricuspid pressure gradient, and mitral regurgitation.

^c Model 2+ Adjustment for Generalized Anxiety Disorder 7-item scale, Patient Health Questionnaire-2, and Cantril’s Ladder of Life.

CI: confidence interval, OR: odds ratio.

The number of subjects included in each model varied depending on data availability due to missing values.

 Association between gardening factors and CHARGE-AF score

Fig. 2 and Supplemental Table 1 show the association between the content of gardening activities and CHARGE-AF score. Among the patients engaged in gardening, 54% were engaged in gardening <4 times/week, while 46% were engaged in gardening ≥4 times/week. After adjusting for age, sex, and various physical, clinical, and psychological parameters, both of these gardening subgroups had lower CHARGE-AF scores than the non-gardening group. The reduction was significant in the group engaged in gardening <4 times/week. There was no significant association between the increased frequency of gardening and CHARGE-AF scores. Among the patients engaged in gardening, 12% were engaged in gardening for <30 min/session, while 88% were engaged for ≥30 min/session. After adjusting for parameters, both of these gardening subgroups had lower CHARGE-AF scores than the non-gardening group; however, this difference was not significant. Furthermore, there was also no significant association between increased gardening duration and CHARGE-AF scores. The median years of experience among the patients engaged in gardening was 20 (10–40) years. Approximately 37% of the patients had the least experience [10 (5–10) years], 30% had moderate experience [22 (20–30) years], and 33% had the most experience [50 (40–60) years]. After adjusting for parameters, all the experienced subgroups had lower CHARGE-AF scores than the non-gardening group, with a significant difference observed in the group with the most experience. Furthermore, there was a significant association between greater gardening experience and CHARGE-AF scores (p for trend = 0.049). Among the patients engaged in gardening, 10% were engaged in planter gardening, 40% in home gardening, 30% in non-commercial outdoor gardening, and 10% in commercial outdoor gardening. After adjusting for parameters, all these gardening subgroups had lower CHARGE-AF scores than the non-gardening group, with a significant difference observed in the group engaged in home gardening. However, there was no significant association between the scale of gardening activities and CHARGE-AF scores.

Fig. 2.  Multivariate analysis of the association of CHARGE-AF score with gardening characteristics.

Abbreviations: AF, atrial fibrillation.

 Comparison between patients with and without AF

An additional analysis was conducted to compare patient characteristics, including gardening activity, between those with and without a history of AF (Supplementary Table 2). No notable difference in the prevalence of gardening activity was observed between the two groups.

 Discussion

The present study is the first to evaluate the association between gardening and the risk of AF development in patients at risk for heart failure and no history of AF. We found that gardening was significantly associated with a lower CHARGE-AF score. Additionally, the extent of gardening (frequency, duration, years of experience, and scale) demonstrated a trend towards a lower risk of AF onset, with a significant association observed only with years of experience.

The onset of AF involves the autonomic nervous system, with the simultaneous activation of the sympathetic and parasympathetic nerves being critical for initiating paroxysmal AF⁷⁾. Regular exercise improves the equilibrium of the autonomic nervous system and stabilizes the functions of the sympathetic and parasympathetic nerves by enhancing heart rate variability²⁴⁾. Furthermore, exercise can improve metabolic disorders such as hypertension and diabetes, which are risk factors for AF. This could indirectly suppress the onset of AF^2,3).

The association between AF onset and exercise therapy has been documented^3,25,26). Exercise therapy suppresses the risk of AF onset. Furthermore, vigorous physical activity is associated with a decrease in AF and ventricular arrhythmias²⁷⁾. A meta-analysis determined that adhering to guideline-recommended physical activity levels (≥450 MET-min/week) is significantly associated with a substantial reduction in the risk of AF onset²⁵⁾ . Another study reported that moderate physical activities, particularly leisure-time activity and walking, significantly reduces the incidence of AF in older adults²⁸⁾. A prospective cohort study involving 91,389 person-years (median 14.7 years) of Japanese individuals demonstrated that frequent stair climbing reduces risk of AF²⁹⁾. The association between various forms of physical activity and a reduced risk of AF has also been demonstrated. Given that gardening requires a certain level of physical activity⁴⁾, it can be considered a form of exercise. Thus, this may account for the inverse association between gardening and CHARGE-AF scores observed in the present study. Huxley et al. reported, based on a large prospective cohort study, that physical activity—including activities such as gardening—was associated with a modest reduction in the risk of AF, particularly among men³⁰⁾.

Furthermore, their findings indicated that physical activity may mitigate the elevated risk of AF associated with obesity. These results lend support to our observation that gardening, as a form of physical activity, may play a contributory role in lowering the risk of AF.

Although exercise decreases cardiovascular events in a curvilinear manner, exceeding the optimal amount of exercise training may decrease these health benefits³¹⁾. This concept may also apply to AF. Although physical activity is associated with a reduction in AF risk and recurrence, excessive endurance exercise can increase the risk of AF onset³²⁾. Thus, the relationship between exercise intensity and AF risk is complex. For instance, the risk of AF onset in the general population is higher in individuals with low exercise tolerance than in those with high exercise tolerance²⁶⁾. The association between exercise intensity and AF onset is multifaceted. For example, athletes engaging in endurance exercise have a higher risk of AF onset than non-athletes³³⁾. However, in older adults, neither low- nor high-intensity exercise is associated with a reduction in AF²⁸⁾. These findings indicate that a moderate amount of physical activity might reduce the risk of AF onset.

In our study, gardening and a greater gardening experience were significantly associated with lower CHARGE-AF scores. However, increased frequency, extended duration, and larger scale of gardening were not significantly associated with lower CHARGE-AF scores. This indicates that although gardening itself can reduce AF risk, excessive gardening does not further suppress AF onset. Nevertheless, although not statistically significant, all types of gardening activities demonstrated a trend towards lowering AF risk. Thus, further prospective studies are required to validate these findings.

Gardening is a form of occupational or horticultural therapy that reportedly contributes to mental stability without the need for extensive physical activity^6,12,34). In the present study, the gardening group demonstrated better psychological indicators, such as the Cantril’s Ladder of Life score, compared to the non-gardening group.

Psychological factors are known to contribute to the development of atrial fibrillation (AF)⁸⁾, and it is therefore plausible that the emotional stability provided by gardening may play a role in reducing AF risk. In recent years, increasing attention has been paid to the association between negative affectivity—including anxiety, anger, depression, and occupational stress—and the incidence of AF. It has also been suggested that autonomic dysfunction may be both a cause and consequence of AF itself⁹⁾. A 2022 meta-analysis of 13 cohort studies demonstrated that psychological distress significantly increases the risk of developing AF, with relative risk increases of 10% for anxiety, 15% for anger, 25% for depression, and 18% for work-related stress⁹⁾. Although our study does not establish causality, psychological stress is a recognized risk factor for AF, and the mental health benefits of gardening may contribute to its prevention.

In contrast, when we examined patients with a history of AF, gardening activity was not significantly different compared to those without AF. This discrepancy may reflect the different pathophysiological stages of AF, where lifestyle factors such as gardening may exert a greater preventive influence in the earlier, preclinical phase. Once AF is established, its presence may be driven more by structural or electrical remodeling and less modifiable by behavioral factors. Therefore, our findings suggest that gardening may be particularly beneficial in the prevention of AF onset, rather than in modifying its course once diagnosed.

 Limitation

The study results should be interpreted while considering the study limitations. This study was an observational study. Thus, causal relationships could not be determined. Since gardening is a common hobby among older adults, intervention studies are challenging to implement. However, incorporating gardening into cardiac rehabilitation protocols might validate the current results. Another limitation of this study was that it was carried out at a single center in a regional city in Japan with a significant patient base involved in agriculture. To determine the broader applicability of our study results, multi-center studies across different regions are required to validate our findings. The age range of the patient population was skewed towards older individuals, making it a limitation of the study. Therefore, future studies should include patients across a broader age range. Another study limitation was that the primary study outcome was not the occurrence of AF itself but the CHARGE-AF score as a surrogate marker to predict AF risk. In the future, prospectively following patients to identify the actual onset of AF will be required to validate the accuracy of this marker. In the present patient cohort, the effect of alcohol consumption was not evaluated. Alcohol intake is reportedly associated with the AF onset³⁵⁾. Although alcohol consumption was not a strong predictor of AF onset in the CHARGE-AF cohort, this confounding factor may be relevant to the current results. Finally, the physical and psychological effects of gardening on the enrolled patients were not directly assessed. In future studies, detailed measures of the exercise intensity involved in gardening activities should be established.

 Conclusions

The present study results demonstrate that gardening is associated with a lower CHARGE-AF score, which is a surrogate marker to predict AF risk, in patients at the outpatient cardiology clinic. Additionally, years of experience demonstrated a trend towards a lower risk of AF onset. Because this study was an observational study conducted at a single facility, evaluations via multicenter intervention studies is warranted in the future.

 Acknowledgments

The authors would like to thank Mayu Ninomiya, Natsumi Ichii, Rumi Taniguchi, Ayako Kinoshita, Keiko Furuno, Kiyomi Mukai, Keiko Ogura, and Mamoru Morino for their assistance in compiling the survey data. We utilized AI-assisted technology for language translation in our study. Special thanks to Professor Takuya Sugahara for his valuable advice from the perspective of the agricultural field.

 Author Contributions

TT, MS, TS, and OY contributed to the study concept and design. TT, MS, MK, TS, HN, KF, SS, TF, and KN contributed to the data acquisition. TT, MS, and OY were responsible for interpretation of data. TT and MS were responsible for the analysis and interpretation of data and the drafting of the manuscript. All authors read and approved the final manuscript.

 Conflict of Interest

The authors declare no conflicts of interest related to this manuscript.

 Clinical Trials Registration

This study is a retrospective analysis and, therefore, was not registered in a public trial database.

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