Melancholy or mahjong? Diversity, frequency, type, and rural-urban divide of social participation and depression in middle- and old-aged Chinese: A fixed-effects analysis

The potential benefit of social participation (SP) to one's mental health has been widely acknowledged. Nevertheless, the specific type and amount of SP that is associated with improved depressive symptoms in middle- and old-aged Chinese awaits further investigation. This study aimed to understand the patterns of depression and SP by comparing urban vs rural China, and according to which, measure the associations between changes in SP and that in depressive symptoms. A total of 10,988 community residents aged 45 years and above were selected from wave 1 (2011), wave 2 (2013), and wave 4 (2015) of the China Health and Retirement Longitudinal Study (CHARLS), a nationally representative survey. The fixed-effects analysis was used to explore the association between the changes in diversity, frequency, and type of SP and the changes in depressive symptoms. The results indicated that rural respondents suffered from a significantly higher risk of depression and took less SP than their urban counterparts. Transitioning from no SP to 1 or more types of SP or to a once a week or higher frequency was associated with a decline in depressive symptoms. For urban respondents, playing mah-jong or cards and joining sports or social clubs predicted a decline in depressive symptoms. For rural residents, interacting with friends regularly was associated with fewer depressive symptoms. In conclusion, more diverse and higher frequency of SP was associated with better mental health, while the social significance of SP varied across different types of SP and between rural and urban areas.


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Depression, a non-communicable disease, has attracted wide research and service attention in recent years 45 due to its heavy burden in both developed and developing countries (Malhi & Mann, 2018). Specifically, 46 nearly 350 million people suffer from depressive disorders globally, which is attributable to 12.7% of all-47 cause mortality (Walker et al., 2015). Moreover, other health problems that often ensue from depression, 48 such as type 2 diabetes (Vancampfort et al., 2016), cardiovascular diseases (Seldenrijk et al., 2015), and

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Additionally, rural and urban China represent two distinctive classes (Yip et al., 2007). For instance, due 94 to the household registration (Hukou or "户口" in Chinese) system, compared with their urban counterparts, 95 rural residents are more likely to be farmers with lower level of education and income (Gu et al., 2019), 96 fewer community infrastructures , and also less access to government-sponsored public 97 resources or healthcare services (Li et al., 2016). This is especially true among elderly. The resource-98 deprived context not only triggers higher risk of health problems, but also limits their opportunities to take 99 part in various SP, and in turn, may result in a different behaviour toward SP amongst rural residents (Guo 100 et al., 2018). Moreover, the pathway and mechanism through which social determinants affect health may 101 vary largely between rural and urban areas. For instance, Chen and Meltzer (2008) suggested a significant 102 rural-urban split in the effects of relative income on one's health outcome, and Chen and Crawford (2012) 103 have illustrated that the association between income inequality and health varies across different 104 geographical levels. In this case, the scarcity of studies that investigated the patterns of SP and their 105 association with depression by considering rural-urban disparity warrants the identification of the 106 relationship in the specific rural and urban contexts, in order to improve the validity of findings. 107 108 Furthermore, most of the published studies are cross-sectional considering only observable variables. In 109 this case, the calculated association includes not only the effect of SP, but also that from other unmeasurable 110 or unmeasured individual-level confounding factors, which may be associated with both SP and depression 111 (Croezen et al., 2015). For instance, compared with those who are not very confident, individuals who have 112 a high sense of self-confidence are more likely to participate in various social activities, and also less likely 113 to feel depressed . Additionally, there are some other potential confounding factors, 114 including personality, childhood experience, intellectual abilities, etc. (Croezen et al., 2015). In other words, 115 the association together with the effect size of SP calculated in these studies may be overestimated, which 116 may risk resulting in spurious correlation or effect. 117 118 Therefore, this study was carried out with two aims: 1) to understand the prevalence of depression and 119 patterns of SP in middle-and old-aged Chinese by comparing urban vs rural China; and 2) to examine the 120 association between SP and depressive symptoms in urban and rural China by taking different dimensions 121 of SP into consideration. In order to account for the endogeneity and to reduce biases associated with 122 omitted time-invariant variables, a fixed-effects analysis was used to examine the association between the 123 changes in SP and that in depressive symptoms.  156 (Boey, 1999). Several studies have reported a cut-off point of 12 with good validity to identify clinically 157 significant depression (Cheng et al., 2016;Cheng & Chan, 2005). Accordingly, a score of 12 was used as 158 the cut-off point to describe the prevalence of depression, whereas the CES-D 10 score was used in the 159 fixed-effects analysis to examine the association between changes in SP and changes in depressive 160 symptoms during waves 1, 2 and 4. 161 162

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In waves 1, 2, and 4 of CHARLS, respondents were asked whether they had conducted the following six 164 types of SP in the last month: a) interacting with friends; b) playing mah-jong, chess, cards or going to 165 other community clubs; c) going to a sport, social or other clubs; d) taking part in a community-related 166 organisations; e) undertaking voluntary or charity work; f) providing help to relatives, friends or neighbours 167 who do not live with the respondent for free. Besides the conventional types of SP, we also considered 168 using Internet as one type of SP, given that prior studies have attributed using Internet to a new type of 169 social activity, through which, senior adults can communicate with social ties, and therefore, be socially 170 connected and gain social support by overcoming the barriers posed by mobility and activity limitations 171 (Cotten et al., 2012(Cotten et al., , 2014. Meanwhile, the CHALRS also included using Internet into one of the options 172 to this question. If the respondents answered "yes" to any of the aforementioned SP, they were asked about 173 the frequency accordingly (almost daily/ almost every week/ not regularly).

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In this study, we examined SP from three aspects: 176 1) Diversity: the total number of different types of SP one conducted. It was coded as: None/ 1 type/ ≥ 2 177 types; 178 179 2) Frequency: the maximum frequency of SP one conducted. Considering that for the majority of these 180 seven types of SP, the proportion of respondents who carried out SP with a frequency of almost daily was 181 less than 0.5%, we then merged the two clusters "almost daily" and "almost every week" and recoded as 182 "≥ 1/week". Therefore, the variable was coded as: None/ not regularly/ ≥ 1/week; 183 184 3) Type of SP (interacting with friends/ mah-jong or cards/ sports or social clubs/ community-related 185 organisations/ voluntary or charity work/ using Internet/ providing help): the frequency of each specific SP 186 was conducted. Since the percentages of respondents who went to sports or social clubs, community-related 187 organisations, or used the Internet with a frequency of once a week or more were less than 1%, we then 188 dichotomised these three types of SP into No/ Yes. Since the prevalence of respondents who took voluntary 189 or charity work was less than 0.2%, whilst providing help to other without financial compensation can be 190 attributed to a type of voluntary work, we then merged these two variables into one named "voluntary 191 activity" following Lin (2017). The frequency was the higher one in these two types of SP and was classified 192 into three groups: None/ not regularly/ ≥ 1/week. For the remaining two variables, including interacting 193 with friends and playing mah-jong or cards, respondents were classified into three groups: None/ not 194 regularly/ ≥ 1/week, in order to conduct subsequent in-depth analysis.

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The following individual-level characteristics were considered as potential confounding variables (Table   198 1). Amongst these variables, gender and residency were time-invariant variables, whereas the rest were

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Underlying reasons might be attributed to: 1) we found that more than 80% of the rural respondents were 375 still working whereas more than 70% did not finish primary school, which indicates that, on the one hand, 376 the heavier financial stress did not leave rural residents much leisure time for these non-profitable social 377 activities, and on the other hand, the lower education may be a barrier to appreciate the benefit of SP (Lin,  This study found that taking part in more diverse social activities and with a once a week or higher 390 frequency predicted a decline in depressive symptoms in both urban and rural residents. Similar findings 391 are seen in prior studies (Guo et al., 2018;Vogelsang, 2016). Moreover, this study also found that the 392 strength of the association mainly depended on residency and type of activity. To be more specific, 393 significantly negative relationship between depressive symptoms and sports or social clubs and mah-jong 394 or cards clubs were observed in urban residents but not rural residents, whereas, interacting with friends 395 was the only type of social activity that was negatively related to depressive symptoms.

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Regarding mah-jong, chess, card playing and other community clubs, to the best of our knowledge, this is 398 the first study that examined the relationship between mah-jong playing, a traditional Chinese entertainment, 399 and depressive symptoms in middle-and old-aged Chinese. This study discovered a significantly negative 400 association between mah-jong playing and depressive symptoms in urban respondents. A similar study 401 (Zhu et al., 2009) suggested that playing mah-jong for entertainment could help one gain more social 402 support, which may result in fewer depressive symptoms. In urban areas, mah-jong is a popular social 403 activity that urban residents usually choose to accompany family members or friends, or to pass the time 404 (Wang, 2014). This is especially the case for residents after retirement. In this case, increased social contacts 405 may be the underlying reason for urban residents to benefit from playing mah-jong. However, mah-jong 406 tends to be a popular type of gambling in rural China (Steinmueller, 2011). Therefore, the eagerness to win 407 and the sense of loss when losing money may offset the potential benefit brought by social network 408 established in mah-jong playing, and may explain the reason why no such negative association was 409 observed in rural residents. This finding, on the one hand, reveals how China's own culture influences one's 410 behaviour and its association with their mental health, and on the other hand, implies that the causal 411 mechanism of mah-jong playing on depressive symptoms worth further investigation in order to develop 412 target policies to promote the mental health of urban residents.

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Regarding sports and social clubs, this study yielded two findings: first, the prevalence rate of joining sports 415 or social clubs in urban areas was more than double of that in rural areas. Second, this type of SP predicted 416 a decline in depressive symptoms in urban areas, whereas the association was not observed in rural areas.

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Combining these two findings, we speculate that joining sports and social clubs is a relatively popular type 418 of SP in urban areas. One who takes part in activities such as square dance and Tai Chi tends to be To the best of our knowledge, the study is the first one to measure the association between social 460 participation and depression in middle-and old-aged Chinese using fixed-effects analysis that rules out the 461 potential endogeneity. By assessing the net association between changes in SP and changes in depressive 462 symptoms, this study confirmed that larger diversity and higher frequency of SP was associated with a 463 decline in depressive symptoms. Meanwhile, this study is also one of the very few studies that took into 464 consideration the rural-urban disparity and mah-jong, one of the most popular means of entertainment, in 465 China's context. The findings revealed huge rural-urban differences in depression, patterns of SP and the 466 association between SP and depressive symptoms, whereas outlined the association between playing mah-467 jong and decline in depressive symptoms in urban areas. These findings not only informed the type and 468 amount of SP that is associated with better mental health, but also reminded the necessity of taking 469 residency and culture into consideration when further investigating the causal relationship, which may 470 contribute to the development of more targeted strategies in China's context.

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The findings should be interpreted with caution because of the following limitations. First, considering both 473 that SP brings contemporaneous effects to depression whereas some short-term benefits may diminish over 474 time (Croezen et al., 2015), and that there was a 2 year timespan between each wave of study (2011,2013 475 and 2015), this study used SP and depressive symptoms in all three waves rather than a lagged model. The 476 sample size in this study was indeed larger than it would be in a lagged model, however, the exact causal