@article {12777, title = {Investigating biological pathways underpinning the longitudinal association between loneliness and cognitive impairment.}, journal = {The Journals of Gerontology, Series A }, year = {Forthcoming}, abstract = {

BACKGROUND: Loneliness precedes the onset of cognitive impairment (CI) in older adults. Although the mechanisms through which loneliness "gets under the skin" to influence the risk of developing CI has been conceptually proposed, they are rarely empirically examined. The Evolutionary Theory of Loneliness posits that loneliness as a stressor could cause dysregulations in multiple physiological systems. The current study investigated whether inflammatory, cardiovascular, and kidney biomarkers mediate the longitudinal association between loneliness and CI.

METHODS: Cross-lagged panel models (CLPM) were used to examine the hypothesized relationships, using 2006, 2010, and 2014 waves of data from the Health and Retirement Study (N=7,037). Loneliness was measured with the 3-item UCLA loneliness scale. CI was assessed with the modified telephone interview for cognitive status. Biomarkers included HbA1C, LDL cholesterol, HDL cholesterol, CRP, and Cystatin C. Using a stepwise model-building approach, first, the model included only loneliness, CI, and biomarker variables; then, sociodemographic covariates were added; lastly, health and behavioral covariates were controlled for.

RESULTS: In unadjusted and partially adjusted models, loneliness was associated with higher odds of worse cognitive status in an 8-year follow-up. Only HbA1C mediated the longitudinal association between loneliness and CI. However, after further controlling for health status, all associations became non-significant.

CONCLUSIONS: Examining a large number of participants and linking a limited number of biological markers with cognition and loneliness longitudinally, our empirical data did not support theoretical propositions, highlighting the critical importance of controlling for confounders in future studies examining longitudinal mediational relationships underlying loneliness and CI.

}, keywords = {Biomarkers, cognitive aging, Epidemiology, Loneliness, Psychosocial}, issn = {1758-535X}, doi = {10.1093/gerona/glac213}, author = {Yu, Kexin and Ng, Ted Kheng Siang} } @article {11149, title = {Longitudinal Assessment of the Relationships Between Geriatric Conditions and Loneliness.}, journal = {Journal of the American Medical Directors Association}, volume = {22}, year = {2021}, pages = {1107-1113.e1}, abstract = {

OBJECTIVES: In response to the lack of longitudinal evidence, this study aims to disentangle time sequence and directionality between the severity of geriatric conditions (GCs) and loneliness.

DESIGN: Longitudinal panel study.

SETTING AND PARTICIPANTS: The working sample had 4680 participants of 2006, 2010, and 2014 waves of the Health and Retirement Study (HRS). All participants were at least 65~years old at baseline. Proxy responded cases and individuals who suffered from moderate to severe cognitive impairment were excluded from the analysis.

METHODS: Loneliness was measured with the 3-item UCLA loneliness scale. Five GCs were included: falls, incontinence, vision impairment, hearing impairment, and pain. Severity indicators were the number of times fallen in the past 2~years, number of days experiencing loss of bladder control in the past month, self-rated eyesight, self-rated hearing, and participants{\textquoteright} perceived level of pain.

RESULTS: Random-intercept cross-lagged panel models were run to analyze the relationship between the severity of each individual GC and loneliness. All models were controlled for baseline demographics, social isolation, self-rated health, physical function, comorbidities, and hospitalization. The longitudinal association between loneliness and fall was bidirectional: a higher loneliness score predicted an increased number of falls and vice versa. Incontinence, vision impairment, hearing impairment, and pain were not significantly associated with loneliness longitudinally. The association between the random intercept of loneliness and some GCs (vision and pain) were significant, indicating the severity of these GCs were related to loneliness at the between-person level at baseline.

CONCLUSION AND IMPLICATIONS: Findings of the longitudinal analysis suggest a reciprocal relationship between fall and loneliness. Fall prevention programs could be integrated with social service for addressing loneliness, and alleviating loneliness might be beneficial for preventing falls. Results of this study highlight the importance of integrating clinical management of falls with social services addressing loneliness in long term care.

}, keywords = {fall, geriatric syndrome, Longitudinal analysis, random intercept cross-lagged panel model, Reciprocal relationships}, issn = {1538-9375}, doi = {10.1016/j.jamda.2020.09.002}, author = {Yu, Kexin and Wu, Shinyi and Yuri Jang and Chou, Chih-Ping and Kathleen H. Wilber and Aranda, Mar{\'\i}a P and Iris Chi} }