Impact of Japan’s Revised Infectious Disease Control Law on Older Adults’ Social Life during the COVID-19 Pandemic
Article information
Abstract
Background
In May 2023, Japan reclassified coronavirus disease 2019 (COVID-19) under the Infectious Disease Control Law. However, there have been insufficient examinations on how the change in classification has impacted citizens’ lives. This study examined the impact of revisions to the Infectious Disease Control Law in Japan on the social frailty and social life of older adults in the community.
Methods
From mid-March to mid-April 2023, a self-administered survey targeting community-dwelling older adults aged 65 years and over was conducted by mail, before the revision of the Infectious Disease Control Law. From mid-February to mid-March 2024, after the revision of the law, a second survey was conducted among those who had responded to the first one. Ultimately, data from 240 cases were collected. The survey included social information such as mask-wearing when going out, status of long-term care insurance, presence of polypharmacy, sleep status, long outings, presence of COVID-19 infection, presence of post-COVID-19 syndrome (if infected), social frailty, and the Kihon Checklist, alongside basic demographic information.
Results
After the revision of the Infectious Disease Control Law, there was an increase in the number of individuals receiving benefits from long-term care insurance and those identified as socially frail. However, no significant differences were observed in the other surveyed items.
Conclusion
The increase in socially frail individuals and those with long-term care insurance suggests that, despite the revision of the Infectious Disease Control Law, the connections within the local community that had once weakened due to the COVID-19 pandemic have not been fully restored.
INTRODUCTION
The coronavirus disease 2019 (COVID-19) pandemic caused many deaths, particularly among older adults with comorbidities such as hypertension, heart disease, and diabetes.1) The Infectious Disease Control Law, serves as a foundation to protect the health and lives of citizens in many countries. In Japan, similar to tuberculosis and severe acute respiratory syndrome COVID-19 was classified as a Category II infectious disease under this law. Furthermore, the public was urged to refrain from non-essential outings, limit contact with others, and maintain social distance.2) These measures restricted the range of activities of Japanese citizens, leading to a decline in physical activity,3) an increase in frailty,4) a decrease in social participation due to increased depression,5) and a decline in sleep quality.6)
As vaccination campaigns spread worldwide7) and severe cases declined, the approach to managing the pandemic changed. In May 2023, Japan reclassified COVID-19 under the Infectious Disease Control Law from Category II to Category V, similar to the influenza virus. Consequently, the legal enforceability of the previous restrictions was lifted, allowing citizens to return to their pre-pandemic lifestyles. However, there have been insufficient examinations on how the change in classification has impacted citizens’ lives. Understanding the trends before and after the revision of the Infectious Disease Control Law could provide valuable insight for assessing the appropriateness of infection control measures for future outbreaks of infectious diseases. In other words, it is necessary to consider the appropriateness of the Infectious Disease Control Law’s measures not only in the short term, but also after the change in classification, in order to assess the validity of its measures. Consequently, this study aimed to investigate social frailty and social life among community-dwelling older adults before and after the change in classification to examine the impact of the revision of the Infectious Disease Control Law on social life.
MATERIALS AND METHODS
A self-administered survey was conducted by mail from mid-March to mid-April 2023. The survey targeted older adults aged 65 years and over who were living in the Chita region of Aichi Prefecture—the region consists of 5 cities and 5 towns, and the aging rate in 2020 was 25.2%. The participants had previously engaged in health check-up projects at Seijoh University and were registered in the university's participant database (only name and address). Questionnaires were dispatched to all 431 individuals enlisted in the database, yielding 349 responses. Subsequent to the exclusion of 30 incomplete surveys, data from 319 individuals were gathered, reflecting a response rate of 74%.
Following the revision of the Infectious Disease Control Law in May 2023, a second survey was conducted from mid-February to mid-March 2024, targeting the 319 respondents from the first survey. Out of 319 questionnaires sent, 250 responses were received. The median age of non-respondents was 78 years, with 33% being male. After excluding 10 cases with missing data, data from 240 respondents were obtained (response rate, 75%). The data from the first survey of these 240 respondents were considered the pre-revision data, and those from the second survey were considered the post-revision data (Fig. 1).
Flow diagram for the inclusion and exclusion of participants.
The questionnaire in the first survey collected information regarding comorbidities (diabetes, hypertension, dyslipidemia, heart disease, cancer, depression, and others); basic information, including age, sex (0=male, 1=female), height, weight, and highest educational attainment (junior high school, high school, vocational school including junior college, university, graduate school, and others); and social information, including the respondent’s adherence to mask-wearing when going out (0=worn, but not always, 1= always), receiving long-term care insurance status (0=no acquisition, 1=requiring support or higher), presence of polypharmacy (0=four or fewer drugs, 1=five or more drugs),8) sleep duration (0=less than 5 hours, 1=6 hours or more), and whether they went out for extended durations exceeding two hours (0=no, 1=yes).
In the second survey, questions regarding comorbidities and highest educational attainment were excluded and replaced with questions about COVID-19 infection history and the presence of post-COVID-19 syndrome. Social frailty was assessed using the Makizako assessment method,9) which has been validated.10,11) Social frailty was determined if respondents met two or more of the following five criteria: (1) living alone (Yes); (2) decreased frequency of going out compared with the previous year (Yes); (3) visiting friends’ homes (No); (4) feeling useful to family or friends (No); and (5) having daily conversations with someone (No). The Kihon Checklist (KCL) comprises 25 yes-or-no questions regarding lifestyle and physical and mental function, with higher scores indicating greater challenges with daily activities (total score).12) In this survey, individuals were classified as having impaired motor dysfunction if they responded yes to three or more of the five items in the motor function domain (Questions #6–10), malnutrition if they responded yes to both items in the nutrition domain (Questions #11 and #12), oral hypofunction if they responded yes to two or all of the three items in the oral function domain (Questions #13–15), social withdrawal if they responded yes to one or both of the items in the withdrawal domain (Questions #16 and #17), cognitive decline if they responded yes to one or more of the three items in the cognitive function domain (Questions #18–20), and depression if they responded yes to two or more of the five items in the depression domain (Questions #21–25; Questions #1–5 do not count). This study was conducted in accordance with the Helsinki Declaration and approved by the Ethics Committee of Seijoh University (Approval No. 2022C0019). The purpose of the study was stated in the questionnaire, and consent to participate in the study was implied through the completion of the questionnaire.
Statistics Analysis
The basic demographic data obtained were expressed as mean±standard deviation for normally distributed data and as median for non-normally distributed data. To compare groups before and after the revision of the Infection Control Law, the Wilcoxon signed-rank test was used for continuous non-normally distributed data. For the analysis of categorical variables, χ2 or Fisher exact tests with Yates’ continuity correction were performed after cross-tabulation. Statistical analyses were conducted using EZR analysis software,13) with statistical significance set to a two-tailed p-value <0.05.
RESULTS
The average age of the participants was 76 years, with approximately 30% being men. A history of COVID-19 infection was observed in 56 respondents (23.3%), among whom, 6 (10.7%) experienced post-COVID-19 syndrome. Hypertension was the most common comorbidity (37.1%), followed by dyslipidemia (20.4%). Regarding educational background, approximately 50% had graduated from high school (Table 1).
Participants’ characteristics (n=240)
In comparing data pre- and post-revision of the Infectious Disease Control Law, there was a substantial increase in the number of individuals receiving benefits from long-term care insurance (p=0.01) and social frailty (p=0.05). However, effect sizes were very low. No changes were observed in mask-wearing when going out, polypharmacy, sleep status, or outdoor time. The KCL scores indicated no changes in the total score or any subitems (Table 2).
Comparison of clinical outcomes before and after revision of the infection law
DISCUSSION
According to reports, COVID-19 has infected 26.5% of the total population in Japan,14) with 10%–20% of infected individuals suffering from post-COVID-19 syndrome.15) The results of this study are consistent with those of previous reports: 23.3% of the participants had COVID-19 infections, and 10.7% experienced post-COVID-19 syndrome. Therefore, this study’s population is considered to reflect the situation in Japan.
This study investigated how social life changed following the revision of the Infectious Diseases Control Law. The findings revealed no significant changes in mask-wearing, sleep conditions, outdoor time, or KCL scores, suggesting stable living conditions. During the COVID-19 outbreak, the government enforced behavioral restrictions and self-restraint measures to prevent further spread of the disease. The public adhered to these measures, judging them as the correct actions to protect their own lives and prevent the spread of the virus, despite facing physical, social, and mental constraints. The emergence of a new lifestyle during this period suggests that social life did not immediately return to normal even after the revision of the Infectious Diseases Control Law.
By contrast, the social life situation may have either remained unchanged or further deteriorated, given the continued increase in the number of socially frail individuals and those receiving benefits from long-term care insurance post-revision of the Infectious Diseases Control Law. Social frailty, linked to decreased participation in social activities and interactions, has been reported to increase the risk of physical frailty.9) According to a survey by the Japanese Cabinet Office,16) 61.6% of respondents reported a decrease in direct communication with others owing to the COVID-19 pandemic, and the percentage of individuals with close friends decreased from 24.7% in 2018 to 7.8% in 2023. Although these findings are from surveys conducted during the pandemic, such situations have been stable post-revision of the Infectious Diseases Control Law. While factors such as mask-wearing, sleep duration, and outdoor time may be subject to individual discretion, social frailty is evaluated in terms of interactions with others and has aspects that cannot be fully addressed alone by individuals. Thus, despite the revision of the Infectious Diseases Control Law, the emergence of new lifestyle patterns during the pandemic, coupled with the persistence of constraints on social life, may contribute to increased social frailty and, consequently, an increase in recipients of long-term care insurance.
The revision of the Infectious Diseases Control Law merely altered the rules regarding COVID-19. It did not eliminate the virus itself. As such, the virus continues to mutate and adapt to its environment.17) Therefore, the threat it poses persists, and the emergence of new lifestyle patterns suggests that social life may not have undergone significant changes in the short term due to the revision of the infectious diseases law. Once restrictions are imposed on people’s lives under the Infectious Diseases Control Law, it has become clear that even if those restrictions are lifted, people would voluntarily continue their normal lives. The reality is that social distancing in the local community will not be immediately restored. However, as this study only investigated short-term trends, conducting research in the medium to long term is necessary. Next, the high response rate, the possibility of conducting a longitudinal survey, the proven usefulness of social frailty assessments, and the KCL in many studies are beneficial in this study.9,10,12) However, while the other questions were general, they had weaker internal validity. Additionally, although the survey results were statistically significant, the effect size was small and did not provide a strong guarantee of clear significance. This point requires careful interpretation. Furthermore, it is important to note that 70% of the respondents were women, and the survey targeted older adults in a specific region. Therefore, there are limitations to the selection bias and external validity, which must be considered.
In conclusion, the revision of the Infectious Diseases Control Law did not lead to significant short-term changes in the social lives of community-dwelling older adults. However, the number of socially frail individuals and recipients of long-term care insurance has increased, and the connections within the local community, which had once weakened, have not been fully recovered. With the revision of the Infectious Diseases Control Law, it is imperative to reconstruct a system that supports the social life of community-dwelling older adults.
Notes
CONFLICT OF INTEREST
The researchers claim no conflicts of interest.
FUNDING
None.
AUTHOR CONTRIBUTIONS
Conceptualization, KI, YK; Data curation, YK; Investigation and methodology, KI, YK, TH; Formal analysis, KI, YK, TY, TH; Writing–original draft, KI; Writing–review & editing, KI, YK, TY, TH.