Table 1 Basic characteristics of participants by occupational noise exposure

Age (years), mean (SD)

36.1 (9.5)

37.6 (9.9)

36.1 (9.5)

< 0.001

Years of occupational hazard exposure, mean (SD)

5.3 (4.7)

5.7 (4.5)

5.3 (4.8)

< 0.001

Sex, n (%)

< 0.001

 Male

550,746 (77.0)

10,930 (69.8)

539,816 (77.2)

 Female

164,389 (23.0)

4,736 (30.2)

159,653 (22.8)

Industry, n (%)

< 0.001

 Manufacturing

616,748 (86.2)

14,010 (89.4)

602,738 (86.2)

 Other industries

98,387 (13.8)

1,656 (10.6)

96,731 (13.8)

BHFTA, mean (SD)

24.6 (11.8)

21.1 (5.8)

24.6 (11.9)

< 0.001

BHFHL, n (%)

/

 Yes

71,647(10.0)

-

71,647(10.2)

 No

643,488(90.0)

15,666(100.0)

627,822(89.8)

SBP (mmHg), mean (SD)

124.2 (14.7)

123.0 (14.9)

124.3 (14.7)

< 0.001

DBP (mmHg), mean (SD)

78.9 (10.4)

77.9 (10.6)

78.9 (10.4)

< 0.001

Isolated systolic hypertension, n (%)

< 0.001

 Yes

21,478 (8.4)

337 (5.6)

21,141 (8.4)

 No

235,311 (91.6)

5740 (94.5)

229,571 (91.6)

Hypertension, n (%)

< 0.001

 Yes

97,861 (13.7)

1691 (10.8)

96,170 (13.8)

 No

617,274 (86.3)

13,975 (89.2)

603,299 (86.2)

Classification of blood pressure, n (%)

< 0.001

 Normal

235,311 (32.9)

5740 (36.6)

229,571 (32.8)

 Prehypertension

381,963 (53.4)

8235 (52.6)

373,728 (53.4)

 Stage 1 hypertension

68,019 (9.5)

1176 (7.5)

66,843 (9.6)

 Stage 2 hypertension

23,287 (3.3)

379 (2.4)

22,908 (3.3)

 Stage 3 hypertension

6555 (0.9)

136 (0.9)

6419 (0.9)

High temperature exposed, n (%)

< 0.001

 Exposed

33,730 (4.7)

1654 (10.6)

32,076 (4.6)

 Non-exposed

681,405 (95.3)

14,012 (89.4)

667,393 (95.4)

Dust exposed, n (%)

< 0.001

 Exposed

306,974 (42.9)

10,125 (64.6)

296,849 (42.4)

 Non-exposed

408,161 (57.1)

5541 (35.4)

402,620 (57.6)

Pb exposed, n (%)

< 0.001

 Exposed

5923 (0.8)

80 (0.5)

5843 (0.8)

 Non-exposed

709,212 (99.2)

15,586 (99.5)

693,626 (99.2)

Benzene exposed, n (%)

< 0.001

 Exposed

52,153 (7.3)

4611 (29.4)

47,542 (6.8)

 Non-exposed

662,982 (92.7)

11,055 (70.6)

651,927 (93.2)