Early life climate and adulthood mental health: how birth seasonality influences depressive symptoms in adults

BMC Public Health

Table 1 Demographic characteristics

Variables	Non-depressive symptoms	Depressive symptoms	Chi-square	OR _adjusted (95%CI)
Variables	N (proportion)	N (proportion)	Chi-square	OR _adjusted (95%CI)
Gender			51.43***
Male	6,392 (84.6%)	1,160 (15.4%)		Ref
Female	6,935 (80.3%)	1,698 (19.7%)		1.38 (1.27,1.50)***
Age (years)			44.80***
18–30	2,239 (85.5%)	381 (14.5%)		Ref
31–45	3,649 (83.9%)	698 (16.1%)		0.91 (0.79, 1.05)
46–60	5,376 (81.1%)	1,253 (18.9%)		1.13 (0.99, 1.30)
> 60	2,063 (79.7%)	526 (20.3%)		1.37 (1.17, 1.60)***
Education			71.96***
Elementary	9,190 (80.7%)	2,199 (19.3%)		1.14 (0.98, 1.32)
Secondary	2,367 (86.2%)	379 (13.8%)		0.87 (0.73, 1.03)
Higher	1,770 (86.3%)	280 (13.7%)		Ref
SES			597.23***
Low	592 (60.0%)	395 (40.0%)		6.13 (5.00, 7.51)***
Middle-low	2,272 (75.0%)	754 (25.0%)		2.91 (2.44, 3.48)***
Middle	4,652 (83.8%)	900 (16.2%)		1.72 (1.45, 2.04)***
Middle-high	4,256 (87.2%)	622 (12.8%)		1.23 (1.03, 1.46)*
High	1,556 (89.3%)	186 (10.7%)		Ref
Geography			48.07***
South	2,791 (85.0%)	492 (15.0%)		Ref
North	1,282 (82.3%)	275 (17.7%)		1.25 (1.06, 1.48)**
Northeast	871 (79.5%)	224 (20.5%)		1.54 (1.28, 1.84)***
East	3,346 (84.0%)	635 (16.0%)		1.27 (1.12, 1.46)***
Central	1,687 (81.0%)	396 (19.0%)		1.36 (1.17, 1.58)***
Southwest	1,311 (80.2%)	324 (19.8%)		1.34 (1.14, 1.57)***
Northwest	2,039 (79.9%)	512 (20.1%)		1.75 (1.52, 2.01)***
Birth seasonality			4.70
Spring	3,265 (82.0%)	718 (18.0%)		1.11 (0.99, 1.25)
Summer	3,354 (81.5%)	760 (18.5%)		1.14 (1.02, 1.29)*
Autumn	3,536 (83.2%)	713 (16.8%)		Ref
Winter	3,172 (82.6%)	667 (17.4%)		1.06 (0.94, 1.20)

Univariate chi-square tests and multiple logistic regression were shown in the table.
CI: confidence interval; OR: odds ratio; Ref: reference; SES: socio-economics; ***p < 0.001; **p < 0.01; *p < 0.05.

ISSN: 1471-2458