Table 1.

Comparison of Study Participants by Severity of Loneliness^*

	No / Low Loneliness (A)			Moderate Loneliness (B)			High Loneliness (C)
	N	Mean	SD	N	Mean	SD	N	Mean	SD	F or X2	p	Post-hoc Significant Comparisons
Number (%)		82 (24%)			184 (54%)			74 (22%)
Sociodemographic
Age (years)	82	60.0	178.0	184	63.0	18.0	74	59.8	19.0	1.26	0.28
Sex (% Female)	82	56.1%		184	47.3%		74	50.0%		1.76	0.41
Race (% Caucasian)	82	76.8%		184	80.4%		74	77.0%		0.63	0.73
Education attainment	79			176			71			2.99	0.56
High school and below		8.9%			9.7%			7.0%
Some college		59.5%			52.3%			63.4%
Graduate school/higher		31.6%			38.1%			29.6%
Marital status (% single)	79	29.1%		176	36.9%		71	53.5%a		9.87	0.007
Living alone (%)	82	9.8%a		177	20.3%		73	34.2%a		14.1	0.001
Personal income	79			170			70			25.9	<0.001
Less than $35,000		31.6%			24.7%a			55.7%a
$35,000 to $49,999		12.7%			14.1%			15.7%
$50,000 to $74,999		16.5%			21.2%			12.9%
$75,000 or more		39.2%			40.0%			15.7%a
Negative psychological traits/states
Depression (PHQ-9)	79	1.1	1.8	181	2.2	2.8	72	4.6	4.4	26.6	<0.001	A < B < C
Anxiety (BSI)	81	0.67	1.8	183	1.3	1.8	74	2.3	2.8	12.1	<0.001	A < B < C
Perceived Stress (PSS)	80	7.9	4.8	181	10.9	4.4	72	15.3	5.7	45.6	<0.001	A < B < C
Positive psychological traits/states
Resilience (CD-RISC)	82	26.3	3.2	180	24.1	3.6	74	21.4	4.4	34.1	<0.001	A < B < C
Optimism (LOTR)	80	34.9	4.8	180	31.3	5.4	74	27.4	6.5	35.7	<0.001	A < B < C
Mental Well-being (SF-36)	82	57.8	4.5	183	55.0	7.0	71	47.7	9.5	41.5	<0.001	A < B < C
Wisdom (SD-WISE)	48	4.26	0.42	122	3.93	0.35	47	3.62	0.39	34.6	<0.001	A < B < C
Subjective Cognition
Cognitive Complaints (CFQ)	81	18.3	10.5	176	27.4	12.8	72	31.1	13.1	22.9	<0.001	A < B < C
Physical health
Physical functioning (SF-36)	82	50.6	9.5	183	47.6	10.3	71	48.6	9.2	2.5	0.083
Loneliness measures
UCLA-3	82	23.9	2.2	184	34.7	4.6	74	51.9	6.8	675.0	<0.001	A < B < C
PROMIS Social Isolation	53	39.3	4.6	136	45.9	5.5	54	56.8	7.1	131.0	<0.001	A < B < C
CESD Item #14	81	0.09	0.28	181	0.26	0.54	74	1.01	0.99	50.3	<0.001	A < B < C

For all measures (except the Cognitive complaints score, loneliness scales, depression, anxiety, and perceived stress), lower scores suggest worse functioning.

BSI = Brief Symptom Inventory – Anxiety subscale; measure of anxiety (Derogatis and Melisaratos, 1983)

CD-RISC = Connor Davidson Resilience Scale; measure of resilience (Connor and Davidson, 2003)

CESD = Center for Epidemiologic Studies Depression Scale; measure of loneliness (Radloff 1977)

CFQ = Cognitive Failures Questionnaire; measure of forgetfulness, distractibility and false triggering (Broadbent 1982, Rast 2008)

LOTR = Life Orientation Test – Revised; measure of optimism (Scheier 1994)

PHQ-9 = Patient Health Questionnaire-9; measure of depression (Kroenke 2001)

PROMIS = Patient-Reported Outcomes Measurement Information System

PSS = Perceived Stress Scale; measure of perceived stress (Cohen 1983)

SD-WISE = San Diego Wisdom Scale; measure of wisdom (Thomas 2017)

SF-36 = Medical Outcomes Survey - Short Form 36; measure of mental and physical functioning (Ware and Sherbourne 1992)

UCLA-3 = UCLA Loneliness Scale (Version 3); measure of loneliness (Russell 1996)

^*Cutoff for loneliness

UCLA-3 Total score < 28 = No/Low Loneliness

UCLA-3 Total score 28 – 43 = Moderate Loneliness

UCLA-3 Total score >43 = High Loneliness

^aPost-hoc Chi-square tests were significantly different at the Bonferroni-corrected p-value level