背景：寂寞感是主觀性地覺得缺乏人際互動的親密感或互動的深度。透過衡量社會網絡大小，多樣性或社交互動的頻率，可測量社交隔離的程度，是故社交隔離是客觀上整體社交接觸程度的減少。過去文獻多著重在討論寂寞感或社交隔離對健康產生的影響，但很少有文獻會一起討論寂寞感與社交隔離對憂鬱症狀、身體失能、與發炎狀態的影響，甚至區別寂寞感與社交隔離對憂鬱症狀、身體失能與發炎狀態的影響。
目的：探索寂寞感與社交隔離對中高齡者健康風險如憂鬱、身體失能與發炎狀態的差異。
方法：本研究使用台灣老人健康之社會因素與生物指標研究（Social Environment and Biomarkers of Aging Study, SEBAS）2000年與2006年兩波針對台灣地區中老年人身心社會與生理指標具有全國代表性的追蹤調查資料庫。以SEBAS 2000年做為基準，分析其孤獨感與社交隔離於第二波SEBAS 2006年追蹤的憂鬱症狀、失能程度與發炎標記的影響。扣除資料疏漏無法分析與簡易心智狀態問卷調查小於八分(SPMSQ<8)的個案，共納入629名54歲以上的個案依據寂寞感與社交隔離的有無分成四組(寂寞感/社交隔離：有/有、有/無、無/有、無/無)並以無寂寞感且無社交隔離的組別做為參考組進行階層迴歸分析(Hierarchical regression)
結果：相較於無寂寞感與無社交隔離組別，具寂寞感與社交隔離的組別對憂鬱症狀經人口學變項、原憂鬱症狀與共病的校正後仍呈現正相關(β=1.73, 95% 信賴區間=0.13-3.33)。然而在有寂寞感無社交隔離組與無寂寞感但有社交隔離組經原憂鬱症狀校正後，原寂寞感與社交隔離狀態與六年後的憂鬱症狀均呈現兩者無相關性。另外，經校正原活動失能程度之後，相較於無寂寞感與無社交隔離組，其餘三組於原寂寞感與社交隔離與六年後的活動失能均呈現無相關性。儘管在具寂寞感與社交隔離組及無寂寞感但有社交隔離組兩組在原寂寞感與社交隔離狀態與六年後的工具性日常生活活動能力失能呈現正相關 (寂寞感/社交隔離：有/有：β=1.92, 95% CI=0.78-3.06); 無/有：β=1.35, 95% CI=0.57-2.13)，然經人口學變項、共病與原工具性日常生活活動能力失能校正之後，兩者則無統計學上之差異。有趣的是，只有在有寂寞感卻無社交隔離組發現原寂寞感與社交隔離狀態與六年後的神經內分泌指標如尿液可體松濃度(β=10.21, 95% CI=4.26-16.17)、血液介白質6濃度(β=2.76, 95% CI=0.77-4.77)與血液高敏感度C-反應蛋白(hsCRP)濃度呈正相關(β=0.41, 95% CI=0.20-0.63)，這些相關性經人口學變項、共病、與原憂鬱狀態校正後仍呈現正相關。相對於寂寞感與社交隔離組在寂寞感與社交隔離與憂鬱症狀的正相關性，寂寞感與社交隔離對神經內分泌指標可能受到人口學病項、共病狀態等影響而掩蓋其相關性。
結論：寂寞感與社交隔離對憂鬱症狀、身體失能與發炎反應均有不同的差異與影響，其因果關係仍有待未來進一步研究與證實。

Background: Loneliness is a subjective measure by an individual to perceive as lack of closeness or depth from interpersonal relationship. Social isolation is a measure of objectively scarce social contact between an individual and the society and social isolation is often measured by social network size, diversity or frequency of social activity. Previous studies mostly focused on either loneliness or social isolation. There is limited study investigating simultaneously the association of loneliness and social isolation with depressive symptoms, disability, and inflammation status. The different impacts of loneliness and social isolation on depression, physical disability, and inflammation status remain unexplained.
Aim: To explore the discrepant risk of loneliness and social isolation on depressive symptoms, physical disability, and inflammation markers.
Methods: Two waves of the Social Environment and Biomarkers of Aging Study (SEBAS), a nationally representative sample of adults who were 45 and over in Taiwan, collected in 2000 and 2006, were used. SEBAS 2000 was used as a baseline, and we have excluded Short Portable Mental State Questionnaire (SPMSQ) scores <8 with missing data, and followed the outcome measurements of the same sample such as the Center for Epidemiologic Studies Depression Scale (CES-D), mobility scale, instrumental activities of daily living(IADL) scale in SEBAS 2006. Total 629 participants aged 54 years and over were enrolled and separated into four groups (Lonely and Isolated; Lonely/Not Isolated; Not Lonely/But Isolated; Not Lonely/Not Isolated.). Hierarchical regression was applied for analysis.
Results: Compare with Not Lonely/Not Isolated group, Lonely and Isolated group at baseline was positively associated with depressive symptoms 6-year later (β=1.73, 95%CI=0.13-3.33) after adjusting for demographic variables, baseline depressive symptoms, and comorbidities. However, Lonely/Not Isolated and Not Lonely/But Isolated groups showed no association between combination of loneliness and social isolation at baseline with depressive symptoms 6-year later after adjusting for baseline depressive symptoms. There were no groups presented with significant association between combination of loneliness and social isolation at baseline and mobility disability 6-year later after adjusting baseline mobility disability. Although both Lonely and Isolated group and Not Lonely/But Isolated group showed positive association between combination of loneliness and social isolation at baseline and IADL disability 6-year later (Lonely and Isolated group:β=1.92, 95% CI=0.78-3.06; Not Lonely/But Isolated group: β=1.35, 95% CI=0.57-2.13), there were no significant associations after adjusting for demographic variables, comorbidities, and baseline IADL disability. Interestingly, only Lonely/Not Isolated group showed positive association between combination of loneliness and social isolation at baseline and neuroendocrine biomarkers levels 6-year later(urine cortisol level(β=10.21, 95% CI=4.26-16.17), serum Interleukin-6 level(β=2.76, 95% CI=0.77-4.77), and serum high sensitivity C- reactive protein (hsCRP) level(β=0.41, 95% CI=0.20-0.63)). These associations remained robust with control variables including demographic variables, comorbidities, and baseline depressive symptoms. In contrast, Lonely and Isolated group associated with depressive symptoms may be masked by comorbidity and demographic variables.
Conclusion: There are different impacts between loneliness and social isolation on depressive symptoms, physical disability, and inflammation status. Causal relationship is warranted for further investigation.

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