Table 1.

Baseline (2006–2008) characteristics of the study sample stratified on loneliness and symptoms of anxiety and depression in the follow-up (2017–2019)

Variables measured at baseline	Total	Young-HUNT3 2006–2008 (Baseline)		HUNT4 2017–2019 (Follow-up)
		Loneliness		Anxiety symptoms		Depression symptoms
		No.	%	No.	%	No.	%
Study cohort	2293	189	8.2	380	16.6	141	6.1
Missing		159	6.9	844	36.8	844	36.8
Gender
Girls	1320	135	10.7	278	30	91	9.8
Boys	973	54	6.2	102	19.7	50	9.7
Age
13–15 years	857	55	7.1
16–19 years	1436	134	10
23–25 years	501			102	31.5	43	13.3
26–29 years	1792			278	24.7	98	8.7
Adolescent mental health
HSCL ≥ 2	434	135	33.5	132	46.8	52	18.5
HSCL < 2	1826	54	3.1	243	21.3	87	7.6
Resilience
Low	626	141	23.8	143	35	69	16.8
High	1607	47	3.1	226	22.7	68	6.8
Relationship with family
Bad	50	17	34.7	15	41.7	13	37.1
Good	2102	172	8.3	340	25.6	118	8.9
Self-esteem
Low	832	160	20.4	208	37.5	86	15.5
High	1419	29	2.2	166	19.2	53	6.1
School satisfaction
Not satisfied	448	100	22.7	100	37.6	49	18.4
Satisfied	1687	85	5.1	252	23.2	77	7.1
Socio-economic status
Low	179	46	26.1	44	37.6	20	16.8
Middle-class	334	22	6.7	66	30.1	20	9.1
High	1626	118	7.3	244	23.9	88	8.6

Adolescents within the loneliness variable category “Quite a lot” and “Very much” Hospital Anxiety and Depression scale ≥ 8