Sustained Post-Intervention Effects of Small Community Walking on Physical Activity, Well-Being, and Social Capital Among Older Patients With Cardiovascular Disease in the Chronic Phase　― A Follow-up Multicenter Randomized Controlled Trial ―

Abstract

Background: Because the sustained effects of physical activity (PA) and the positive psychological and social aspects during the chronic phase of cardiac rehabilitation (CR) have not been clarified, we examined the sustained post-intervention effects of small community walking (SCW) on PA, well-being, and individual-level social capital in older patients with cardiovascular disease (CVD) in the chronic phase and the influence of increased well-being and social capital on increased PA.

Methods and Results: The subjects were 48 older patients with CVD who were randomly divided into SCW and walking-alone groups and were available for a 6-month follow-up survey after a 3 months’ intervention by healthcare workers. We measured PA, well-being (subjective happiness scale), and social capital before, 3 months after the intervention, and 6 months after the intervention ended. At 6 months post-intervention, only the SCW group maintained significant increases from the pre-intervention values in PA and well-being (P<0.01). Furthermore, increased well-being was a predictor of increased PA in the SCW group (P<0.01).

Conclusions: Our results suggest that SCW effectively maintains PA and well-being, even after the intervention ends, in older patients with CVD during the chronic phase. In addition, the effects of SCW are associated with PA and well-being. The relationship between PA and individual-level social capital should be further investigated.

In Japan, the Ministry of Health, Labour and Welfare reported in 2021 that cardiovascular disease (CVD) was the second leading cause of death, with 214,623 deaths due to cardiac disease. Cardiovascular preventive measures have become an urgent issue, and the JCS/JACR 2021 Guidelines for rehabilitation of patients with cardiovascular disease recommend that patients with CVD receive cardiac rehabilitation (CR) throughout their lifetime.¹ Therefore, we have focused on incorporating physical activity (PA) into the daily life of CVD patients in the chronic phase. Reduced PA in older patients with CVD leads not only to all-cause deaths, rehospitalization, and recurrence of CVD, but also to frailty and impaired cognitive function.^2–10 Therefore, it is important for older patients with CVD to increase and maintain their PA,¹¹ but sustaining increased PA is difficult in the chronic phase of CR,^12–14 and little evidence of effective interventions is available.

Kubzansky et al. summarize the importance of well-being and social capital to “cardiovascular health”,¹⁵ and in Japan, the National Plan for Promotion of Measures Against Cerebrovascular and Cardiovascular Disease has been formulated with the aim of extending healthy life expectancy.¹⁶ The plan recommends the realization of “community involvement,” in which people connect with each other and create opportunities for fun and a reason for living. In addition, the importance of social support and removing social isolation have been emphasized in the JCS/JCC/JACR/JATS 2024 Guideline on cardiovascular practice with consideration for diversity, equity, and inclusion.¹⁷ Therefore, we believe promoting and maintaining positive factors, such as well-being and social capital, are very important for older patients with CVD. However, methods for continuously improving these factors during the chronic phase of CR have not yet been developed.

We focused on the strategy of small community walking (SCW), in which patients walk with friends or family members in groups of 3, as a CR method for patients with CVD in the chronic phase. In our previous study, patients with CVD were randomly divided into 2 groups: the SCW group and the walk-alone (WA) group. A healthcare professional conducted exercise guidance for patients with CVD once a month for 3 months to investigate changes in PA, well-being, and individual-level social capital.¹⁸ Both PA and civic participation in social capital increased in both groups after the intervention. Furthermore, well-being significantly increased in the SCW group. However, whether these effects continued after the intervention ended was unknown. Previous research has shown that walking in groups of 3 continued to increase PA, even after the intervention ended, and PA has been shown to be related to well-being and social capital.^19–22 Therefore, we hypothesized that the SCW intervention would maintain increases in PA, well-being, and individual-level social capital in older patients with CVD after the intervention ended. Additionally, changes in well-being and social capital were assumed to affect PA.

Against this background, the purpose of the present study was to investigate the hypotheses by following up on the effects of the SCW and WA interventions on PA, well-being, and social capital 6 months after the intervention ended. Furthermore, we examined the influence of increased well-being and social capital on increased PA. We present the results of the follow-up study conducted in 2022 after an intervention within the Kumamoto City Cardiovascular Disease Prevention Model Project in 2021.

Methods

Study Design and Subjects

This multicenter, prospective, randomized controlled trial was conducted at 10 medical institutions in Kumamoto City, Japan. The subjects were categorized into heart failure stages B and C according to the JCS 2017/ JHFS 2017 Guideline on diagnosis and treatment of acute and chronic heart failure and the JCS/JHFS 2025 Guideline on diagnosis and treatment of heart failure.^23,24 The study protocol and the results before and after intervention have been described in detail previously.¹⁸ Briefly, for the protocol, we used a computer-based procedure to randomize CVD patients aged 60–80 years referred from neighborhood medical institutions into SCW and WA groups of 29 and 26 patients, respectively, who were available to be evaluated before and after the intervention. Randomization was performed using randomly permuted blocks and stratum allocation according to sex. Patients with severe pain that caused walking difficulties, those with cognitive decline, and those who were already walking in groups were excluded.

This study examined 48 patients (SCW group 26, WA group 22) who were evaluated by follow-up survey 6 months after the intervention ended. A flowchart of the study is presented in Figure 1.

Figure 1.

Flow diagram of the 2 groups’ progress through the phases of the randomized trial. SCW, small community walking; WA, walking alone.

Study Intervention

Healthcare providers instructed the subjects on PA once a month for 3 months. The participants in the SCW group were informed that they would walk in groups of 3 with close friends and/or families as buddies approximately once weekly for a 3-month intervention. When participants in the SCW group were unable to find buddies, we introduced volunteers to walk with them. Patients in the WA group walked alone. At the follow-up survey after the 3-month intervention, the participants were not required to walk with a peer. However, they could decide whether to walk in groups. Both groups underwent the 3-month intervention between September 2021 and February 2022. The follow-up was performed 6 months after the end of the 3-month intervention, and the participants were evaluated between June and September 2022. The following were assessed before the intervention in both groups: age, body mass index (BMI), smoking status, living alone, duration of chronic phase, CR, exercise time (min/week), CVD, coronary risk factors, medications, blood pressure, heart rate, medical data (white blood cells, aspartate aminotransferase (AST), alanine aminotransferase (ALT), albumin, estimated glomerular filtration rate (eGFR), triglycerides, high-density lipoprotein (HDL) cholesterol, low-density lipoprotein (LDL) cholesterol, hemoglobin A1c (HbA1c), and B-type natriuretic peptide (BNP); echocardiography for left ventricular ejection fraction (LVEF), which is systolic function, and E/e’, which is diastolic function). We also evaluated physical function as used in CR (6-minute walking distance (6MWD) and frailty using the J-CHS criteria).^25–29 PA, well-being, and social capital were measured before, 3 months after, and 6 months after the intervention ended. The personnel assessing the outcomes were blinded to the group allocations and differed from those providing the PA intervention. However, participants were not blinded to their allocation. All the participants provided written informed consent to participate in the study, which was approved by the Ethics Committee of Kumamoto Kinoh Hospital (JMC-347-2116). The study was conducted in accordance with the Declaration of Helsinki. The study is registered with the University Hospital Medical Information Network (UMIN) Clinical Trials Registry (ID: UMIN000046132).

Outcomes Measurements

The primary endpoint was PA; using a watch-type wearable device (Inspire2, Fitbit Japan), the average daily step count for 2 weeks was calculated based on the number of steps recorded in the application.

Secondary endpoints were well-being and individual-level social capital. Well-being was assessed by the subjective happiness scale described in Lyubomirsky and Lepper’s report.^30,31 We calculated well-being by averaging the responses to 3 items. Individual-level social capital was civic participation, social cohesion, and reciprocity, referring to Saito et al.’s report in which participants responded to 5 questions on a 6-point rating scale.³² In terms of social cohesion, the participants responded to 3 items on a 5-point rating scale. For reciprocity, participants responded to 3 items on a 7-point rating scale. Individual indicators were calculated for individual-level social capital using simple addition.

Statistical Analysis

The effect size and power of the 48 participants were calculated using the G*Power 3.1.9.7. The sample size of this study was calculated with a partial η2 of 0.08 and a 2-tailed α level of 0.05, resulting in an effect size of 0.29 and a power of 0.97, which was considered sufficient. For participants’ backgrounds, nominal variables are indicated by nominal values and percentages, and continuous and ordinal data are indicated by median values (minimum–maximum value). We analyzed the differences before the intervention using the Mann-Whitney U-test or the Chi-square test, which was used for PA and social capital, and the Kolmogorov-Smirnov test to identify the normality of data. For comparisons before the intervention, 3 months after the intervention, and 6 months after the intervention ended, 2-way split plot design analysis of variance (SPANOVA) was used for PA and social capital, and post hoc analyses were conducted using simple main effects. The Friedman test was used for well-being. Spearman›s rank correlation coefficient was used to correlate the change rates [6 months after the intervention ended – before the intervention) / before the intervention] of PA, social capital, and well-being to examine the factors that influence PA. Factors with a correlation coefficient of P<0.2 with PA were extracted, and multiple regression analysis was conducted using a mixed effect model. The Chi-square test was used to compare the post-intervention walking behaviors of each group, specifically whether they engaged in WA or SCW, or did not walk. A 2-way ANOVA was used to compare the PA levels within the SCW group, depending on continued post-intervention SCW. The significance level was set at P<0.05. Data were analyzed using Statistics (version 20.0; IBM Corp., Tokyo, Japan).

Results

Before the intervention, there were no significant differences between groups in BMI, current smoking status, family structure, duration of chronic CR, exercise time, medical history, medications, blood pressure, pulse rate, medical data, PA, frailty, 6MWD, social capital items, or well-being (Table 1).

Table 1.

Comparison of the Clinical Characteristics of the SCW and WA Groups

	All (n=48)	SCW group (n=26)	WA group (n=22)	P value
Age (years)	72 (61–79)	72 (61–79)	72 (65–79)	0.34
Sex (male/female), n (%)	32 (66.7)/16 (33.3)	16 (61.5)/10 (38.5)	16 (72.7)/6 (27.3)	0.84
BMI (kg/m2)	23.7 (16.6–30.5)	23.1 (16.6–30.5)	24.4 (19.2–30.0)	0.15
Current smoker, n (%)	4 (8.3)	2 (7.7)	2 (9.1)	0.63
Living alone, n (%)	7 (14.6)	3 (11.5)	4 (18.2)	0.40
Duration of maintenance phase CR (years)	5 (0.5–20)	5 (1–20)	5 (0.5–18)	0.30
Exercise (min/days)	90 (0–600)	95 (0–600)	50 (0–500)	0.29
Cardiovascular disease
Ischemic heart disease, n (%)	28 (58.3)	15 (57.7)	13 (59.1)	0.92
Valvular heart disease, n (%)	4 (8.3)	2 (7.7)	2 (9.1)	0.63
Cardiomyopathy, n (%)	4 (8.3)	1 (3.8)	3 (13.6)	0.24
Heart failure, n (%)	9 (18.8)	6 (23.1)	3 (13.6)	0.32
Coronary risk factors
Obesity (BMI ≥25), n (%)	12 (25.0)	5 (19.2)	7 (31.8)	0.32
Hypertension, n (%)	40 (83.3)	22 (84.6)	18 (81.8)	0.55
Dyslipidemia, n (%)	26 (54.2)	13 (50.0)	13 (59.1)	0.53
Diabetes mellitus, n (%)	13 (27.1)	8 (30.8)	5 (22.7)	0.53
Medications
ACE, n (%)	4 (8.3)	2 (7.7)	2 (9.1)	0.63
ARB n, (%)	14 (29.2)	8 (30.8)	6 (27.3)	0.79
β-blocker, n (%)	18 (37.5)	9 (34.6)	9 (40.9)	0.65
Diuretic, n (%)	7 (14.6)	3 (11.5)	4 (18.2)	0.40
Calcium-channel blocker, n (%)	28 (58.3)	17 (65.4)	11 (40.9)	0.28
Anticoagulant, n (%)	16 (33.3)	7 (26.9)	9 (40.9)	0.31
Antiplatelet, n (%)	20 (41.7)	11 (42.3)	9 (34.6)	0.92
Systolic blood pressure (mmHg)	127 (92–148)	127 (92–148)	127 (105–140)	0.82
Diastolic blood pressure (mmHg)	70 (46–88)	69 (60–85)	70 (46–88)	0.56
Heart rate (beats/min)	70 (45–96)	68 (45–96)	70 (56–94)	0.92
LVEF (%)	63 (30–85)	62 (30–85)	63 (30–77)	0.24
E/e′	10.8 (6.9–32.0)	10.5 (7.4–21.1)	11.3 (6.9–32.0)	0.58
Laboratory results
WBC (×103/μL)	5.7 (2.6–8.5)	5.7 (4.5–8.5)	5.8 (3.6–8.5)	0.91
AST (IU/L)	23 (14–52)	24 (14–47)	26 (17–52)	0.15
ALT (IU/L)	22 (10–70)	19 (11–45)	24 (10–70)	0.09
Albumin (g/dL)	4.4 (3.8–5.0)	4.4 (3.6–4.9)	4.4 (3.8–5.0)	0.28
eGFR(mL/min)	65 (35–117)	65 (47–117)	67 (35–95)	0.89
TG (mg/dL)	148 (44–365)	146 (44–365)	150 (50–361)	0.84
HDL-cholesterol (mg/dL)	51.8 (33.6–99.3)	53.4 (33.6–87.1)	47.6 (38.5–99.3)	0.52
LDL-cholesterol (mg/dL)	88 (23–204)	95 (23–204)	86 (62–164)	0.71
HbA1c (%)	5.9 (4.8–6.8)	6.0 (5.1–6.8)	5.9 (4.8–6.7)	0.63
BNP (pg/mL)	24.1 (5.8–168.2)	26.6 (5.8–168.2)	22.9 (5.8–99.9)	0.53
Physical activity (steps/days)	6,810 (793–17,000)	6,888 (2,715–12,943)	6,691 (793–17,003)	0.65
6MWD (m)	400 (220–640)	395 (280–560)	420 (220–630)	0.38
Frailty, n (%)	4 (15.4)	3 (10.3)	1 (3.8)	0.63
Subjective happiness scale	5.0 (1.0–7.0)	5.3 (2.3–6.3)	5.0 (1.0–7.0)	0.23
Social capital
Civic participation	18.7 (12.0–21.0)	17.2 (12.0–21.0)	19.0 (12.5–21.0)	0.90
Social cohesion	4.8 (2.4–8.3)	4.8 (3.1–7.2)	4.8 (2.4–8.3)	0.58
Reciprocity	13 (3–46)	13 (3–46)	16 (3–33)	0.54
Type of buddies in SCW
Family, friends/volunteers, n (%)	–	24 (92.3)/2 (7.7)	–	–

Data are presented as median (min−max) or number (percent). 6MWD; 6-minute walking distance; ACE, angiotensin-converting enzyme inhibitor; ALT, alanine aminotransferase; ARB, angiotensin II receptor blocker; AST, aspartate aminotransferase; BMI, body mass index; BNP, B-type natriuretic peptide; CR, cardiac rehabilitation; E/e′, early mitral filling velocity/early diastolic mitral annular velocity; eGFR, estimated glomerular filtration rate; HbA1c, hemoglobin A1c; HDL, high-density lipoprotein; LDL, low-density lipoprotein; LVEF, left ventricular ejection fraction; TG, triglycerides; WBC, white blood cells.

Two-way SPANOVA showed a significant interaction between group and period for PA (SCW: 7,144±2,305 → 8,891±1,881 → 8,274±2,693, WA: 7,561±4,078 → 9,513±3,501 → 7,609±3,512, F (1, 46)=3.98, P=0.04, Figure 2A). Main effect showed a significant increase in the SCW group at 3 months after the intervention and 6 months after the intervention ended compared with before intervention (before the intervention vs. 3 months after the intervention P<0.01, 6 months after the intervention ended P<0.01), while in the WA group, there was an increase at 3 months after the intervention compared with before the intervention (P<0.01), but a decrease at 6 months after the intervention ended (P<0.01).

Figure 2.

Comparisons of physical activity, well-being, and social capital in SCW and WA groups pre-intervention and post 3 months, and post-intervention 6 months. (A) physical activity, (C) social cohesion, (D) civic participation, and (E) reciprocity analyzed using 2-way repeated-measures analysis of variance and simple main effects as post hoc. (B) Well-being measured using a subjective happiness scale and analyzed using Friedman test. Data are expressed as mean±standard deviation. SCW, small community walking; WA, walking alone.

Only the SCW group showed a significant increase in well-being at both 3 months and 6 months after the intervention ended compared with the baseline (SCW: 4.3±1.0 → 5.5±1.2 → 5.6±0.8, P<0.01; WA: 4.6±0.9 → 5.5±1.2 → 4.7±1.1 P=0.17, Figure 2B).

Furthermore, the results demonstrated that both social cohesion and civic participation significantly improved during the study period in both groups. Namely, there was a significant improvement in social cohesion 6 months after the intervention ended compared with before the intervention (SCW: 6.1±1.4 → 6.2±1.9 → 6.0±1.8, WA: 6.0±1.6 → 6.2±1.4 → 5.9±1.5, P=0.04, Figure 2C). In civic participation, significant improvements were found both 3 months and 6 months after the intervention ended compared with before the intervention (SCW: 26.0±3.5 → 23.3±3.4 → 24.2±3.9, WA: 26.3±3.2 → 24.5±5.1 → 24.9±4.1, P<0.01, Figure 2D). No significant differences were found in reciprocity (SCW: 16.1±12.1 → 19.0±14.2 → 16.1±13.2, WA: 18.4±10.3 → 16.4±10.5 → 14.7±9.0, Figure 2E).

To identify the factors influencing PA, we first examined the relationship of PA with well-being and social capital variables (Table 2A). Next, the variables with P<0.2 for the correlation coefficient were extracted, and a multiple regression analysis was conducted with PA as the dependent variable and well-being, social cohesion, and the interaction terms well-being*group and cohesion*group as independent variables (Table 2B). The results showed that the factors influencing PA were the interaction terms of the well-being*group (P<0.01). Finally, as a subgroup analysis, we conducted a multivariate analysis separately in the SCW and WA groups (Table 2C). The results showed that well-being influenced PA in the SCW group (P<0.01). However, none of these factors influenced PA in the WA group. Table 3 shows the post-intervention walking continuation status of each group. The Chi-square test revealed a significant difference between the groups (χ²=16.783, P<0.01). Residual analysis showed that the WA group had a higher number of participants who discontinued walking than in the SCW group, whereas the SCW group had a higher number of participants who continued SCW than in the WA group. In addition, PA levels improved significantly during the study period regardless of whether SCW continued post-intervention (P<0.01). Specifically, significant improvements were observed at 3 months (P<0.01) and 6 months (P=0.03) post-intervention, compared with the baseline (Table 4).

Table 2.

Correlations and Multiple Regression Analysis of Physical Activity With Well-Being and Social Capital

(A) Correlations of physical activity with well-being and social capital	Physical activity
	r	P value
Well-being	0.29	0.04
Social capital
Social cohesion	−0.17	0.08
Civic participation	−0.25	0.24
Reciprocity	−0.04	0.79
(B) Multiple regression analysis for physical activity using a mixed effect model	Physical activity
	β	P value
Well-being	−0.11	0.64
Group	−0.15	0.28
Social cohesion	−0.15	0.66
Well-being*group	1.40	<0.01
Social cohesion*group	−0.19	0.67
(C) Subgroup analysis of multiple regression analysis for physical activity	SCW group			WA group
	β	P value	VIF	β	P value	VIF
Well-being	0.59	<0.01	1.05	−0.07	0.77	1.25
Social capital
Social cohesion	−0.15	0.36	1.07	−0.20	0.42	1.16
Civic participation	−0.23	0.17	1.07	−0.10	0.69	1.08
Reciprocity	0.13	0.44	1.06	−0.20	0.45	1.25

Well-being measured using a subjective happiness scale. (A) Confirmed the correlation coefficient for physical activity using Spearman’s rank correlation coefficient. (B) Confirmed standardized partial regression coefficient for physical activity using multiple regression analysis of mixed effect model. Adjusted R squared was 0.25. (C) Divided into SCW and WA groups and used multiple regression analysis to confirm standardized partial regression coefficients for physical activity. Adjusted R squared was 0.39 in SCW group and −0.09 in WA group. The dependent and independent variables in each table are percent change [(6 months after the intervention ended − before the intervention) / before the intervention]. β, standardized partial regression coefficient; SCW, small community walking; VIF, variance inflation factor; WA, walking alone.

Table 3.

Methods of Post-intervention Walking Continuation in Each Group

	Non-walking	WA	SCW
SCW group, n	6	6	14§
WA group, n	12*	10	0

P<0.01, χ² value 16.783, degrees of freedom 2. *Non-walking is WA group > SCW group. ^§SCW group > WA group. SCW, small community walking; WA, walking alone.

Table 4.

Comparison of Physical Activity With and Without Continuation of SCW After the Intervention in the SCW group

	SCW continuing group (n=15)			SCW non-continuing group (n=11)			Main effect of time	Interaction
	Pre- intervention	Post 3 months	Post- intervention 6 months	Pre- intervention	Post 3 months	Post- intervention 6 months
Physical activity (steps/day)	6,651±2,512	8,337±1,926	8,387±2,427	7,816±1,892	9,646±1,602	9,184±3,079	P<0.01	P=0.78

Data are expressed as the mean±standard deviation. In both groups, post-3 months, post-intervention 6 months > pre-intervention. SCW, small community walking; WA, walking alone.

Discussion

This study examined the prolonged effects of SCW on PA, well-being, and social capital among older patients with CVD in the chronic phase. Interestingly, the SCW group maintained significant increases in PA and well-being until 6 months after the intervention ended. However, the WA group did not show any increase or continued effects 6 months post-intervention.

The results of this study suggest that SCW may be an effective strategy for maintaining PA in older patients with CVD in the chronic phase, even after the intervention ends. Previous studies in older women and young adults have demonstrated a similar lasting effect of 3 people walking on increasing PA.^33,34 We assume that the mechanism of the lasting effect is changing individual behavior by leveraging “peer pressure” from peers and family members, which has been reported previously.³⁵ In addition, the novel finding is that our study confirmed the prolonged effect of SCW on PA without financial incentives, which have shown some advantage to continue PA in previous studies.^33,34

In order to improve the prognosis, quality of life, and cardiovascular health of older patients with CVD in the chronic phase, it is necessary to enhance well-being in addition to PA.^2,15,36–38 Therefore, it was important that the SCW intervention also showed a prolonged effect on well-being. Previous studies have shown that PA enhances subjective well-being through social networks and positive emotions.^39,40 In addition, Pop reported that the physical, mental, and social benefits of group exercise enhance body image and affect subjective well-being.⁴¹ Based on these earlier study findings, we believe that SCW can also enhance positive emotions and body image through social networks, an exercise which is useful for enhancing subjective well-being.

This study examined the association between the rate of change in PA and well-being before and 6 months after the intervention ended. Increased well-being was related to increased PA in the SCW group. Although the mechanism has not been clarified, several previous studies have shown a relationship between PA and well-being; that is, the relationship between increased PA and well-being may be interactive.^{20,21,42–44} Therefore, the causal relationship between PA and well-being needs further investigation. To the best of our knowledge, this is the first longitudinal study to show that group walking for patients with chronic CVD continues to increase well-being, even after the intervention ends, and that this effect relates to PA. Based on these findings, SCW may be an effective and simple method for improving the prognosis of older patients with chronic CVD. However, the adherence rate of SCW after the intervention ended was approximately 58%. Sustaining CR in the chronic phase is an important issue.^6,12–14 DeBusk et al. reported that the adherence rate of exercise therapy for 1 year in patients with acute myocardial infarction was <50%.¹³ In a previous report by Moore et al., the adherence rate at 1 year after the outpatient CR ended was 15%.¹⁴ The adherence rate of SCW was higher than in those previous studies, which may relate to the effect of walking with family and friends. Clark et al. qualitatively investigated the factors that sustained CR in patients with coronary artery disease and the factors they identified were the safety of CR and camaraderie.⁴⁵ Therefore, we believe that the continuation of SCW in our study was because 3 people walking increases human relationships and camaraderie. Additionally, SCW may be valuable as a means to easily exercise in small groups without the requirement to use facilities. However, 42% of the participants gave up SCW during the study period, and the reasons why they could not continue are unknown because a follow-up survey of those who dropped out was not conducted. Two participants in the SCW group who walked with volunteers dropped out because they felt bad walking in groups with volunteers for a long time. We also assume that it could be difficult to schedule walking times in groups of 3. However, approximately 23% of those who discontinued SCW continued walking alone and maintained their PA levels. Furthermore, walking interruptions decreased to a greater extent in the WA group. Notably, PA levels were maintained post-intervention, regardless of continuation of SCW. Future studies should explore strategies for sustaining engagement with SCW and the relationship between buddy types and PA.

We do not oppose WA, as increased PA benefits patients with CVD. Considering that some patients with CVD prefer not to walk in groups, CR instructors should develop strategies to inform patients of the specific advantages of group walking, thereby enabling them to choose between SCW and WA.

Individual-level social capital has an important role in social cohesion and civic participation. Social cohesion significantly improved at 6 months post-intervention from baseline. In addition, civic participation significantly improved at both 3 months after the intervention and 6 months post-intervention compared with the baseline. Although previous research has revealed a relationship between individual-level social capital and PA, the causal relationship has not yet been clarified.^19,20,46,47 Ichida et al. examined the effects of promoting social participation through “community salon” participation on self-rated health and their results showed that the self-rated health of the “community salon participants” was 2.52-fold higher than that of “non-salon participants”.⁴⁸ Additionally, it has been reported that the risk of long-term care was reduced in older people who participated in sports organizations rather than alone, even at the same exercise frequency.⁴⁹ These previous studies suggest that the strategy of walking in the community as a group may improve social capital and health in patients with CVD. However, further large-scale studies are required to confirm these findings.

Study Limitations

This study had several limitations. First, due to the study period, it is unclear whether it will affect PA over a longer period of time. Long-term follow-up studies are required. Second, a causal relationship between PA and well-being could not be established due to the study design. Third, in the subgroup analysis using multiple regression for the independent variables, the small number of participants increased the possibility of overfitting. Therefore, further studies involving larger cohorts are warranted. Fourth, information on buddy type was limited to age and sex, and information on friends and family was not available. Therefore, the PA levels, age, and sex of all the buddies were unknown. Future studies should examine the effects of the sex and age of the buddies on the effectiveness of SCW. Finally, the participants in this study may be a population with a high awareness of PA, as their cardiac function, physical function, and instrumental activities of daily living were well maintained. Furthermore, although we investigated pre-intervention exercise habits, we did not specifically confirm the walking habits, allowing for the possibility that pre-intervention walking habits influenced the findings.

Conclusions

The results of this study suggest that a SCW intervention may increase PA and well-being among older patients with CVD in the chronic phase, and that these effects last 6 months after the intervention ends. The effects of SCW are related to the association between PA and well-being. Walking in a group in a familiar neighborhood may positively affect individual-level social capital in older patients with CVD.

Acknowledgments

This study was supported by Kumamoto City Office. The authors acknowledge the contributions made in this study by all enrolled patients, participating cardiologists, and other medical professionals at the 10 medical institutions in Kumamoto City (listed in the Appendix).

Sources of Funding

The Kumamoto City Office supported this study as part of the Kumamoto City Cardiovascular Disease Prevention Model Project in 2022, as well as the Japan Sports Agency in 2021.

Disclosures

The funding bodies are Kumamoto City and Japan Sports Agency. The authors declare no conflicts of interest. K. Tsujita is a member of Circulation Reports’ Editorial Team.

Conflict of Interest

The authors have no conflicts of interest to disclose.

Data Availability

The deidentified participant data will not be shared.

IRB Information

The study protocol was approved by Kumamoto Kinoh Hospital (JMC-347-2116) and the ethics committees of the participating institutions. All participants provided written informed consent to participate in the study.

Appendix

The 10 medical institutions that participated in this study: Ueki Hospital, Kumamoto Kinoh Hospital, Kumamoto Seijyo Hospital, Sakurajyuji Hospital, Seigato Hospital, Seijino Rehabilitation Hospital, Tanoue Cardiac Rehabilitation Hospital, Nishinihon Hospital, Miyuki Hospital, Yamato Clinic.

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