Physical Therapy Korea

Cardiovascular diseases, including coronary heart disease and stroke, are the leading cause of global mortality and disease burden [1]. The mortality rate from cardiovascular diseases is 105.5 per 100,000 individuals, according to the 2021 cause of death statistics published by the Statistics Korea [2]. Consequently, several countries have emphasized the significance and necessity of cardiac rehabilitation.

Increasing evidence supports the effectiveness of cardiac rehabilitation in reducing mortality and morbidity [3], and enhancing exercise capacity, quality of life, and psychological well-being [4]. The prognostic effectiveness of cardiac rehabilitation in patients with heart failure, ischemic heart disease, and other cardiovascular conditions, has led to its increased recommendation in clinical practice guidelines worldwide [5,6].

Characterization of epidemiological patterns using extensive big data analysis has become crucial for effective prevention and therapeutic strategy formulation. A comprehensive epidemiological study aids in preventing diseases by identifying individuals with high-risk based on known risk factors and supports the development of tailor-made prevention programs for these individuals [7]. In Korea, interest in cardiac rehabilitation therapy has been increasing along with increasing recommendation for therapy after recognition of cardiac rehabilitation as a benefit item in the National Health Insurance Service in 2017. However, few epidemiological studies have characterized cardiac rehabilitation therapy in Korea. Furthermore, data on trends in cardiac rehabilitation therapy based on national big data is limited.

Therefore, in this study, we aimed to characterize the national epidemiological data for cardiac rehabilitation therapy in Korea from 2017 to 2023 and to stratify the findings based on age and sex using the Health Insurance Review and Assessment (HIRA) Service database.

The HIRA database, also known as the Korean National Health Insurance database includes health insurance claims data, generated during the reimbursement process of healthcare services under the National Health Insurance system in Korea. HIRA data include medical billing information of the entire Korean population with 97% of the population covered by health insurance and 3% covered by medical care [8,9]. In Korea, the inclusion of patient medical records including prescription codes in the HIRA database is a legal requirement. The authors obtained and analyzed data related to cardiac rehabilitation therapy in South Korea from 2017 to 2023.

In the HIRA database, the prescriptions related to cardiac rehabilitation are MM451, MM452, and MM453 (Table 1). Among them, only MM453 provided by a physical therapist was included in the analysis. According to the Korean Medical Service Act, cardiac rehabilitation therapy is provided based on the patient’s condition; however, it is allowed twice a day for inpatients and up to 36 times for outpatients. Furthermore, it is provided by one physical therapist for up to four patients simultaneously, if provided for > 60 minutes per patient. The cardiac rehabilitation therapy data extracted included the total number of cases per year and incidence of cardiac rehabilitation therapy prescriptions per 100,000 people/year along with sex and age distribution of patients undergoing cardiac rehabilitation therapy. The incidence per 100,000 people per year was calculated based on additional information from surveys, including basic epidemiological data, in accordance with Statistics Korea. Line graphs were employed to illustrate trends by sex and age, as sample data was not used.

Table 1 . Diagnostic code for cardiac rehabilitation of the HIRA.

Code	Diagnostic code
MM451	Cardiac rehabilitation education
MM452	Cardiac rehabilitation evaluation
MM453	Cardiac rehabilitation therapy

HIRA, Health Insurance Review and Assessment..

This study protocol was reviewed and approved by the relevant Institutional Review Board (IRB) at Inje University Ilsan Paik Hospital (IRB no. ISPAIK 2023-12-009). The IRB waived the requirement for informed consent owing to the use of anonymized data.

The total number of prescriptions for cardiac rehabilitation therapy in 2017 was 4,443 and it increased to 15,646 by 2023 (Figure 1) with a 252.1% increase over a 7-year period. The incidence per 100,000 person-years was 8.64 in 2017 and increased to 30.22 in 2023 (Figure 2).

Figure 1. Total number of cardiac rehabilitation therapy patients per year stratified by sex.

Figure 2. Incidence of cardiac rehabilitation therapy per 100,000 person-years stratified by sex.

In terms of sex distribution, the prevalence of prescriptions for cardiac rehabilitation therapy was higher in males (approximately 70%) than that in females (approximately 30%) throughout the study period. Among men, the total number of patients and incidence were 3,183 and 12.35, respectively, in 2017, increasing to 11,276 and 43.53, respectively, by 2023 (Figures 1, 2). Among females, the total number of patients and incidence per 100,000 person-years were 1,260 and 4.91, respectively, in 2017, increasing to 4,370 and 16.89, respectively, in 2023 (Figures 1, 2).

In terms of age, the highest number of prescriptions were observed in the 60s group, followed by the 70s, 50s, and > 80s groups (Figure 3). In the 60s group, the total number of patients and incidence were 1,386 and 2.70, respectively, in 2017, increasing to 4,747 and 9.17, respectively, by 2023 (Figures 3, 4).

Figure 3. Total number of cardiac rehabilitation therapy patients per year stratified by age.

Figure 4. Incidence of cardiac rehabilitation therapy per 100,000 person-years stratified by age.

The study revealed that cardiac rehabilitation therapy prescription consistently increased in Korea from 2017 to 2023. Moreover, males underwent the procedure 2.6 times more frequently than females. Furthermore, the highest utilization was observed among individuals in their 60s. Cardiac rehabilitation therapy is essential for patients with heart disease. Thus, understanding the national trends and epidemiology of cardiac rehabilitation therapy utilization are critical for future planning and national policy development. Few reports have characterized the national trends and epidemiology of cardiac rehabilitation therapy around the world [10-14]. To the best of our knowledge, this is the first study to report the national trends of cardiac rehabilitation therapy in Korea.

Overall, 1,903,563 patients with heart diseases were included in the HIRA database by 2023 (disease codes I05–I09, I20–I27, and I30–I52). In 2023, only 15,646 patients underwent cardiac rehabilitation therapy, accounting for 0.9% of all patients with heart disease. Approximately 20 years ago in Germany, 117,983 inpatients in Germany underwent cardiac rehabilitation therapy between 2000 and 2005 [15]. In Japan, among 2,046,302 patients diagnosed with cardiovascular disease from 2010 to 2017, 595,733 (29%) underwent cardiac rehabilitation therapy [14]. Comparatively, the number of patients undergoing cardiac rehabilitation therapy in Korea remains significantly less than that in other countries with a notably slower rate of development. Furthermore, the number of prescriptions for pulmonary disease exercise rehabilitation therapy (MM440) covered by health insurance increased from 2,856 in 2017 to 17,374 in 2023, reflecting a substantial growth of 508.3% over 7 years as per the data from the HIRA database. While, the increase in cardiac rehabilitation therapy prescriptions is relatively modest. Therefore, these findings highlight the need for increased focus and strategic development for increasing the accessibility and efficacy of cardiac rehabilitation therapy in Korea.

In China, the number of patients receiving cardiac rehabilitation per year increased from 15 in 2013 to 5,183 in 2021 [16]. In Japan, the number of cardiac rehabilitation participants has also increased annually; in particular, the inpatient cardiac rehabilitation participation rate has increased significantly from 18% in 2010 to 40% in 2017 [14]. Cardiac rehabilitation density is the highest in the USA with 1 program per 102,000 inhabitants; while, middle-income countries have approximately 1 program per 1–6 million individuals [11]. In Korea, cardiac rehabilitation has been covered under insurance since February 2017 owing to the increased significance of procedures and postoperative rehabilitation for patients with heart disease. Currently, 47 hospitals nationwide provide cardiac rehabilitation [17]; thus, the number of patients undergoing cardiac rehabilitation has increased.

In terms of sex distribution, the prevalence of prescriptions for cardiac rehabilitation therapy was higher in males (approximately 70%) than that in females (approximately 30%) during the study period. Similarly, in Canada, cardiac rehabilitation enrollment among females was significantly lower than that among men, with females being 36% less likely to enroll in a rehabilitation program [18]. Moreover, a Chinese study revealed that the males participated more frequently in cardiac rehabilitation than females (men-to-females ratio, 1.8:1) [16], similar to the trends reported in the United States and Canada [11,18]. The authors reported that a lack of awareness, comorbidities, higher frailty burden, fear of physical pain with exercise, and traffic difficulties are factors that contributing to this sex disparity [16].

In terms of age, the highest number of cardiac rehabilitation prescriptions were observed in the 60s groups, followed by 70s, 50s, and ≥ 80s groups in South Korea in 2023. In Denmark, most individuals participating in cardiac rehabilitation treatment were aged ≥ 65 years, followed by individuals aged ≥ 75 years [10]. Moreover, Zhang et al. [16] reported that the majority of participants in cardiac rehabilitation treatment in China were under 60 years old, followed by individuals aged 60–70 years and those aged ≥ 70 years. A common feature of South Korea and other countries is that patients aged > 60 years account for the largest proportion of participants undergoing cardiac rehabilitation therapy. First, because the incidence of cardiovascular disease increases with age with many patients aged > 60 years undergoing cardiac rehabilitation [19]. Second, this trend may also be due to the decreased mortality rate owing to advancements in surgical procedures [16].

The significance of the present study is based on the study being the first investigation into national trends of cardiac rehabilitation therapy using a comprehensive national database in Korea. Notably, this database is considered one of the most accurate globally, encompassing the entire Korean population, incorporating all medical records, and being under the governance of the Korean government.

Nevertheless, this study has some limitations. First, the potential for coding errors in the vast database cannot be excluded. Second, our analysis excluded participants injured in traffic or industrial accidents, or those who filed claims for automobile liability or industrial injury insurance. However, the number of the excluded patients was likely minimal as compared to the comprehensive data recorded in the HIRA database. The current study did not include statistical analyses and did not assess statistical significance as it was based on an entire database rather than a small sample size. In any study with a sample from a population, the observed results from a small sample may be generalized to the entire population through statistical analysis. However, no such statistical analysis was needed for this study.

The total number of patients undergoing cardiac rehabilitation therapy steadily increases from 2017 to 2023. In Korea, cardiac rehabilitation therapy prescription is approximately 2.6 times more prevalent in males than that in females. Moreover, it is most prescribed to the patients in the 60s age group, followed by those in the 70s, 50s, and > 80s group. The current study aimed to enhance our understanding of the epidemiology of cardiac rehabilitation therapy with a focus on prevention and cost-saving measures in Korea.

None.

This study was supported by Ewha Alumni Medical Research Grant.

No potential conflicts of interest relevant to this article are reported.

Conceptualization: JK, JY. Data curation: SJ, SL. Formal analysis: JK. Investigation: SJ, SL, TS. Methodology: JK, JY. Project administration: TS, JJ. Supervision: JJ, JY. Visualization: SJ. Writing - original draft: JK. Writing - review & editing: TS, JY.