Social Isolation and Patient Experience in Older Adults
=======================================================

* Takuya Aoki
* Yosuke Yamamoto
* Tatsuyoshi Ikenoue
* Yuka Urushibara-Miyachi
* Morito Kise
* Yasuki Fujinuma
* Shunichi Fukuhara

## Abstract

**PURPOSE** Social isolation has been identified as a major health problem, particularly in the elderly. In the present study, we examine the association between social isolation and patient experience in elderly primary care patients.

**METHODS** This cross-sectional study was conducted in a primary care practice–based research network (28 clinics) in Japan. We assessed social isolation using an abbreviated Lubben Social Network Scale and patient experience of primary care using a Japanese version of the Primary Care Assessment Tool (JPCAT), which comprises 6 domains: first contact, longitudinality, coordination, comprehensiveness (services available), comprehensiveness (services provided), and community orientation. We used a linear mixed effects model to adjust clustering within clinics and individual covariates.

**RESULTS** Data were analyzed for 465 elderly primary care patients aged ≥65 years. After adjustment for possible confounders and clustering within clinics, social isolation was negatively associated with the JPCAT total score, (mean difference = −3.67; 95% CI, −7.00 to −0.38). Among the JPCAT domain scores, social isolation was significantly associated with longitudinality, comprehensiveness (service provided), and community orientation scores.

**CONCLUSIONS** Social isolation was associated with negative patient experience in elderly primary care patients. Raising awareness regarding patient social networks among primary care providers and targeted interventions for socially isolated elderly patients aimed at improving the experience of primary care, especially regarding longitudinality, comprehensiveness, and community orientation, may be warranted.

Key words
*   social isolation
*   social capital
*   primary care/general practice
*   patient experience

## INTRODUCTION

Social isolation is defined as a state in which an individual lacks a sense of belonging socially, lacks engagement with others, has a minimal number of social contacts, and displays a deficiency in fulfilling quality relationships.1 Social isolation has been identified as a major health problem, particularly in the elderly who lack good social networks that are a key element of social capital.2 The negative effects of social isolation on health outcomes are supported by a wealth of evidence. According to previous studies, social isolation is associated with increased risk of all-cause mortality,3,4 mortality from coronary heart disease/stroke,5 rehospitalization,6 falls,7 cognitive decline,8 and death from suicide.4 Moreover, socially isolated older individuals are at risk for negative behaviors, such as heavy drinking9 and poor nutritional habits.10

Social isolation may influence health outcomes and patient behaviors by having a negative impact on the patient experience. Patient experience is considered the most effective quality measure of patient-centeredness and is defined as providing care that is respectful of and responsive to patient preferences, needs, and values.11 Patient experience is known to affect health outcomes through patient behaviors, such as adherence to treatment and health care resource use.12,13 Previous studies have reported socioeconomic variation in patient experience,14,15 and a few exploratory quantitative studies have suggested negative associations of social capital components with patient experience.16,17 Additionally, a previous qualitative study identified social isolation as an unmet need in elderly primary care patients.18 Due to a lack of studies, however, an association between social isolation and patient experience of primary care remains unclear. It would be beneficial for primary care providers and policymakers to have a clear understanding of the relationship between social isolation and patient experience.

The aim of this study was to examine the association between social isolation and patient experience in elderly primary care patients.

## METHODS

### Design, Setting, and Participants

The data used for this study were collected from the primary care organizations reciprocal evaluation survey study (PROGRESS) conducted in a primary care practice-based research network19 in Japan from October 2015 to February 2016. The PROGRESS was a cross-sectional survey to collect data on patient experience, health-related quality of life, health conditions, health care utilization, clinical process, and sociodemographic characteristics among adult outpatients in primary care. The primary care practice-based research network where this survey was conducted is part of a national network of primary care clinics belonging to the Japanese Health and Welfare Co-operative Federation and the Japan Federation of Democratic Medical Institutions. The 28 participating clinics are distributed in both urban and rural areas (Tohoku, Kanto, Tokai, Kinki, Setouchi, and Sanin) (Supplemental Appendix 1, available at [http://www.annfammed.org/content/16/5/393/suppl/DC1/](http://www.annfammed.org/content/16/5/393/suppl/DC1/)), with the majority being solo practices. Primary care in these clinics is delivered by family physicians and the majority of patients are aged ≥65 years old. A self-administered questionnaire was distributed to all outpatients aged ≥20 years who visited 1 of the participating clinics within the 3-day survey period, and the completed surveys were collected via mail.

A total of 644 individuals out of 1,939 adult patients (33.2%) responded to the PROGRESS. Among them, participants eligible for this study were individuals aged ≥65 years, for whom the clinic serves as their usual source of care. To identify an individual’s usual source of care in this study, the 3 questions and the algorithm used in the Japanese version of the Primary Care Assessment Tool (JPCAT)20 were the same as those used in the original Primary Care Assessment Tool Adult Expanded Edition21: (1) Is there a doctor that you usually go if you are sick or need advice about your health?; (2) Is there a doctor that knows you best as a person?; and (3) Is there a doctor that is most responsible for your health care?. A patient was considered to have a usual source of care if he or she answered positively to any 1 of the 3 questions.

The ethical committee of the Kyoto University Graduate School of Medicine provided ethical approval for this study (approval number R0184). Written informed consent was obtained from all study participants.

### Measures

#### Social Isolation

We used the Japanese version of the abbreviated Lubben Social Network Scale (LSNS-6)22 to evaluate the social isolation in elderly individuals (Supplemental Appendix 2, available at [http://www.annfammed.org/content/16/5/393/suppl/DC1/](http://www.annfammed.org/content/16/5/393/suppl/DC1/)). The LSNS-6, developed by James Lubben, is used for screening and research of social networks in many countries.23 The LSNS-6 is a 6-item self-reported scale used to assess social isolation in the adults aged ≥65 years old by measuring perceived social support received from family and friends. This tool assesses the size, closeness, and frequency of contacts in a respondent’s social network. The LSNS-6 score is an equally weighted sum of scores on the 6 items. The scores range from 0 to 30 points, with higher scores indicating a better quality of social network. The reliability and validity of the Japanese version of LSNS-6 have been assessed in a previous study in Japan.22 As suggested by Lubben et al, we classified patients with a score of <12 points as being socially isolated.23

#### Patient Experience of Primary Care

We used the JPCAT20 as the patient experience measure of primary care (Supplemental Appendix 3, available at [http://www.annfammed.org/content/16/5/393/suppl/DC1/](http://www.annfammed.org/content/16/5/393/suppl/DC1/)). The JPCAT, based on the Primary Care Assessment Tool Adult Expanded Edition,21 was developed with the Delphi method, cognitive testing, and validation study to establish its applicability to the Japanese health care system. This 29-item tool comprises 6 multi-item subscales representing 5 primary care attributes, including first contact, longitudinality, coordination, comprehensiveness, and community orientation (Supplemental Appendix 4, available at [http://www.annfammed.org/content/16/5/393/suppl/DC1/](http://www.annfammed.org/content/16/5/393/suppl/DC1/)).24 The scoring system of JPCAT is structured as follows: each response on a 5-point Likert scale is converted to an item score from 0 and 4. The means of item scores in the same domain are multiplied by 25 to yield domain scores ranging from 0 to 100 points, with higher scores indicating better patient experience. The total score is the mean of the 6 domain scores and reflects an overall measure of the quality of core primary care attributes. Previous work has shown that the JPCAT has good reliability and validity.20 The primary outcome measure in this study is the JPCAT total score, and secondary outcome measures are the domain scores.

#### Covariates

Covariates were selected for their known associations with social isolation and patient experience. We included covariates for age, sex, years of education, annual household income, self-rated health, and mental health status assessed by the 5-item Mental Health Index of the Japanese 36-item Short Form health survey.25

### Statistical Analysis

To determine whether social isolation was associated with the JPCAT total score, we used a linear mixed effects model (random intercept model) that includes a random effect for clinic, and covariates (age, sex, years of education, annual household income, self-rated health, 5-item Mental Health Index score, and the proportion of isolated patients in each clinic) as fixed effects. The mixed effects model, based on a full information maximum likelihood estimation, was used to enable use of all the information including that from participants with some data missing. We calculated 95% CIs using robust standard errors. In addition, we performed exploratory analyses to investigate the associations between social isolation and each domain score of the JPCAT using the same mixed effects models. For references, a 3-point increase in patient experience measures linearly scaled to a 0-100 range has been associated with a reduction in disenrollment from health plans, thus a difference of >3 points is considered sufficient in magnitude to have practical importance.26–28 We used SPSS Statistics version 23 (IBM Corp) for statistical analyses.

## RESULTS

Of the 644 adult participants who responded to the survey, we excluded 162 participants aged <65 years and 17 participants who did not have a usual source of care. We carried out analyses of the remaining 465 eligible participants.

Table 1 shows the characteristics of the 465 eligible participants. The majority of the participants were females (54.4%), aged ≥70 years (71.8%), with less than college education (79.3%), and with multi-morbidity (74.8%). The proportion of socially isolated patients was 27.3%. The average JPCAT total score was 65.7 out of 100 points; the most highly scored domain was longitudinality with 81.2 points, and the most poorly scored domain was comprehensiveness (services provided) with 45.8 points. Table 1 also compares the characteristics of the socially isolated participants with participants who were not socially isolated. We noted a trend suggesting that the socially isolated participants had lower JPCAT scores and 5-item Mental Health Index scores.

View this table:
[Table 1](http://www.annfammed.org/content/16/5/393/T1)

Table 1 
Characteristics of Study Participants

Table 2 shows the results of the linear mixed effects model, examining the associations between social isolation and the JPCAT scores as measures of patient experience in primary care. Social isolation was negatively associated with the JPCAT total score, after adjustment for possible confounders and clustering within clinics (mean difference = −3.67; 95% CI, −7.00 to −0.38). Among the JPCAT domain scores, social isolation was significantly associated with longitudinality, comprehensiveness (service provided), and community orientation scores. Comprehensiveness (service provided) had the strongest association with social isolation (mean difference = −7.58; 95% CI, −14.28 to −0.88).

View this table:
[Table 2](http://www.annfammed.org/content/16/5/393/T2)

Table 2 
Associations Between Social Isolation and JPCAT Scoresa (N = 465)

## DISCUSSION

Our results revealed that social isolation was associated with a more negative patient experience of primary care, especially regarding longitudinality, comprehensiveness (services provided), and community orientation, among older Japanese patients who had a usual source of care. Based on previous results, a JPCAT total score difference of >3 points between socially isolated and not socially isolated patients in our study is considered sufficient in magnitude to have practical importance.

Our findings agree with previous exploratory study results about the associations between elements of social capital and patient experience.16,17 Although having a social network is a crucial element of social capital, the association between social isolation and patient experience has been unclear. The results of our study contribute additional information about potential mechanisms by which social isolation influences health outcomes and patient behaviors. According to a previous qualitative study, service providers experience substantial levels of concern and frustration and have a sense of powerlessness about meeting the needs of socially isolated patients29; however, there remains a lack of relevant data on what their care needs are. Our study identified longitudinality, comprehensiveness, and community orientation as unmet needs in socially isolated elderly patients in primary care. These findings might be helpful for primary care providers to address the needs of socially isolated patients; further studies are needed.

To the best of our knowledge, this is the first study to reveal the association between social isolation and the patient’s experience of primary care. Our findings were based on data from a nationwide multicenter primary care practice-based research network study covering both urban and rural areas and included a wide range of local health care delivery systems. Patient experiences differ by clinic; therefore, we adjusted clustering within clinics by using a mixed-effects model and allowed appropriate patient-level analysis.

Our study has several potential limitations. First, the participation rate was a concern. A previous study of patient experience surveys showed that a low participation rate did not introduce selective nonresponse bias,30 however, it is possible that patients with lower quality patient experiences or social networks were less likely to respond to our survey. If so, this could cause an underestimation of the association between social isolation and patient experience in this study. Second, in the validation study of the JPCAT, although socioeconomic factors were employed to ensure that the selection of the sampling site represented the Japanese national standard, the sampling site was restricted to 1 urban area. Therefore, there were differences in the participants’ characteristics between the validation study of the JPCAT and this study that included rural practices. Construct validity of the JPCAT, however, has previously been verified in the population of this study.31,32 Third, our survey setting was restricted to primary care clinics that had a known interest in health care quality. Although we covered a nationwide network of primary care clinics, caution should be exercised when generalizing the results of this study.

In conclusion, social isolation was associated with negative patient experiences in elderly primary care patients. Raising awareness about the importance of patient social networks among primary care providers and targeted interventions for socially isolated elderly patients aimed at improving the experience of primary care, especially regarding longitudinality, comprehensiveness, and community orientation, may be warranted.

## Acknowledgments

The authors thank the participating primary care clinics belonging to Japanese Health and Welfare Co-operative Federation and Japan Federation of Democratic Medical Institution.

## Footnotes

*   Conflicts of interest: authors report none.

*   **Funding support:** Pfizer Health Research Foundation, Japan (grant no. 15-9-051).

*   **Previous presentations:** Preliminary results from this work have been presented at the North American Primary Care Research Group Annual Meeting; November 12–16, 2016; Colorado Springs, Colorado.

*   **Supplemental Materials:** Available at [http://www.AnnFamMed.org/content/16/5/393/suppl/DC1/](http://www.AnnFamMed.org/content/16/5/393/suppl/DC1/).

*   Received for publication November 5, 2017.
*   Revision received February 27, 2018.
*   Accepted for publication March 22, 2018.


*   © 2018 Annals of Family Medicine, Inc.

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