Table 2 Baseline characteristics classified according to subsequent onset of depressive symptoms

Age(years)

0.254

0.102

0.653

 45–54

892(77.50)

259(22.50)

823(71.5)

328(28.5)

681(76.35)

211(23.65)

 55–64

1010(80.16)

250(19.84)

911(72.3)

349(27.7)

772(76.44)

238(23.56)

 65–74

477(80.17)

118(19.83)

457(76.81)

138(23.19)

377(79.04)

100(20.96)

  ≥ 75

93(83.04)

19(16.96)

84(75.00)

28(25.00)

73(78.49)

20(21.51)

Sex

 < 0.001

 < 0.001

 < 0.001

 Male

1399(82.34)

300(17.66)

1327(78.10)

372(21.90)

1129(80.70)

270(19.3)

 Female

1073(75.62)

346(24.38)

948(66.81)

471(33.19)

774(72.13)

299(27.87)

Education

0.050

 < 0.001

0.001

 Illiterate

479(75.91)

152(24.09)

424(67.19)

207(32.81)

346(72.23)

133(27.77)

 Less than elementary school

1660(79.65)

424(20.35)

1536(73.70)

548(26.30)

1287(77.53)

373(22.47)

 High school

227(81.65)

51(18.35)

212(76.26)

66(23.74)

175(77.09)

52(22.91)

 Above vocational school

106(84.8)

19(15.20)

103(82.40)

22(17.60)

95(89.62)

11(10.38)

Marital status

0.417

0.866

0.516

 Single

2278(79.46)

589(20.54)

2093(73.00)

774(27.00)

1750(76.82)

528(23.18)

 Married

194(77.29)

57(22.71)

182(72.51)

69(27.49)

153(78.87)

41(21.13)

Current residence

0.003

0.033

0.055

 Rural

2253(78.64)

612(21.36)

2076(72.46)

789(27.54)

1723(76.48)

530(23.52)

 Urban

219(86.56)

34(13.44)

199(78.66)

54(21.34)

180(82.19)

39(17.81)

Smoking status

0.060

 < 0.001

0.008

 No

1394(77.88)

396(22.12)

1251(69.89)

539(30.11)

1041(74.68)

353(25.32)

 Former smoke

222(82.84)

46(17.16)

205(76.49)

63(23.51)

177(79.73)

45(20.27)

 Current smoke

856(80.75)

204(19.25)

819(77.26)

241(22.74)

685(80.02)

171(19.98)

Alcohol consumption

0.029

 < 0.001

 No

1545(77.99)

436(22.01)

1388(70.07)

593(29.93)

1156(74.82)

389(25.18)

 Less than once a month

208(78.79)

56(21.21)

189(71.59)

75(28.41)

156(75.00)

52(25.00)

 More than once a month

719(82.36)

154(17.64)

698(79.95)

175(20.05)

591(82.2)

128(17.8)

Having regular exercises

0.880

0.812

0.885

 No exercise

1484(79.27)

388(20.73)

1371(73.24)

501(26.76)

1147(77.29)

337(22.71)

 Less than exercises

488(78.71)

132(21.29)

446(71.94)

174(28.06)

372(76.23)

116(23.77)

 Regular exercises

500(79.87)

126(20.13)

458(73.16)

168(26.84)

384(76.80)

116(23.20)

Taking activities

0.019

0.021

0.127

 No

1104(77.42)

322(22.58)

1012(70.97)

414(29.03)

834(75.54)

270(24.46)

 Yes

1368(80.85)

324(19.15)

1263(74.65)

429(25.35)

1069(78.14)

299(21.86)

Chronic disease(counts)

0.032

0.003

0.226

 0

1034(81.1)

241(18.90)

961(75.37)

314(24.63)

811(78.43)

223(21.57)

 1–2

1155(78.79)

311(21.21)

1063(72.51)

403(27.49)

883(76.45)

272(23.55)

 3–14

283(75.07)

94(24.93)

251(66.58)

126(33.42)

209(73.85)

74(26.15)

BMI changes

0.194

0.468

0.459

  > -3%

436(75.69)

140(24.31)

1027(74.58)

350(25.42)

873(78.72)

236(21.28)

 -3–3%

1109(80.54)

268(19.46)

412(71.53)

164(28.47)

327(75.00)

109(25.00)

 3–6%

462(79.25)

121(20.75)

418(71.7)

165(28.3)

350(75.76)

112(24.24)

 6–9%

223(79.36)

58(20.64)

199(70.82)

82(29.18)

168(75.34)

55(24.66)

  > 9%

242(80.4)

59(19.6)

219(72.76)

82(27.24)

185(76.45)

57(23.55)