Table 1 Characteristics of the participants by the screening of hypertension in the past, in estimated number of Tibetan people and percentage and 95% confidence interval

Characteristics

Est. N

% (95% CI)

Est. N

% (95% CI)

Est. N

% (95% CI)

p - value

Est. N

% (95% CI)

Overall

64,227

94.9 (93.2–96.6)

15,881

24.7 (22.1–27.3)

48,346

75.3 (72.7–77.9)

3426

5.1 (3.4–6.8)

Gender

0.003

 Male

32,613

93.4 (90.3–96.4)

9835

30.2 (25.1–35.2)

22,778

69.8 (64.8–74.9)

2309

6.6 (3.4–9.7)

 Female

31,613

96.6 (95.3–97.9)

6045

19.1 (15.4–22.9)

25,567

80.9 (77.1–84.6)

1116

3.4 (2.1–4.7)

Age group

<  0.001

 18–39

38,415

96.8 (94.2–99.4)

4393

11.4 (7.6–15.3)

34,022

88.6 (84.7–92.4)

1275

3.2 (0.6–5.8)

 40–59

19,226

92.3 (90.2–94.4)

7013

36.5 (32.9–40.1)

12,212

63.5 (59.9–67.1)

1598

7.7 (5.6–9.7)

 60 +

6585

92.3 (88.7–95.8)

4473

67.9 (61.7–74.2)

2111

32.1 (25.8–38.3)

552

7.7 (4.2–11.3)

Marital status

<  0.001

 Single/separated

7858

96.9 (92.4–100)

3595

45.8 (36.0–55.5)

4262

54.2 (44.5–64.0)

252

3.1 (0–7.0)

 Married

56,368

94.7 (92.8–96.5)

12,284

21.8 (19.1–24.5)

44,083

78.2 (75.5–80.9)

3175

5.3 (3.5–7.1)

Education

0.031

 None

30,351

96.3 (95.1–97.4)

8630

28.4 (24.7–32.2)

21,720

71.6 (67.8–75.3)

187

3.7 (2.5–4.9)

 Primary school

26,191

93.1 (89.8–96.4)

6210

23.7 (19.2–28.2)

19,981

76.3 (71.8–80.8)

487

6.9 (3.5–10.2)

 Middle school and above

7683

96.1 (89.4–100)

1040

13.5 (4.4–22.6)

6643

86.4 (77.4–95.6)

279

3.9 (0.0–10.6)

Occupation

0.096

 Agriculturalist

55,782

96.1 (94.8–97.4)

13,343

23.9 (21.2–26.6)

42,438

76.1 (73.4–78.8)

2240

3.9 (2.6–5.2)

 Herdsman

4294

87.4 (76.5–98.4)

1656

38.6 (24.7–52.5)

2638

61.4 (47.5–75.3)

617

12.5 (1.6–23.5)

 Other

4149

87.9 (74.8–100)

881

21.2 (7.6–34.9)

3269

78.8 (65.1–92.4)

569

12.1 (0--25.2)

Income (CNY),

0.283

  ≤ 2500

54,426

95.0 (93.3–96.7)

13,879

25.5 (22.7–28.3)

40,546

74.5 (71.7–77.3)

2.863

5.0 (3.3–6.7)

 2501–5000

7906

93.9 (87.3–100)

1767

22.3 (13.3–31.4)

6139

77.7 (68.6–86.7)

513

6.1 (0–12.6)

  ≥ 5001

1894

97.4 (92.3–100)

235

12.4 (1.0–23.8)

1659

87.7 (76.2–99.0)

49

2.6 (0–7.6)

Tobacco use

0.902

 Yes

17,447

93.4 (89.2–97.8)

4260

24.4 (18.8–30.0)

13,187

75.6 (70.0–81.2)

1224

6.5 (2.3–10.8)

 No

46,779

95.5 (93.8–97.1)

11,620

24.8 (21.7–28.0)

35,159

75.2 (72.0–78.3)

2202

4.5 (2.8–6.1)

Alcohol use

0.693

 Yes

17,133

97.5 (96.0–99.0)

4048

23.6 (17.0–30.2)

13,085

76.4 (69.7–83.0)

443

2.5 (1.0–4.0)

 No

47,093

94.0 (81.7–96.3)

11,833

25.1 (22.3–28.0)

35,260

74.9 (72.4–77.7)

2983

6.0 (3.7–8.3)

BMI (kg/m²)

<  0.001

  ≤ 23.9 (Normal)

37,148

96.2 (94.4–98.1)

6031

16.2 (13.6–18.9)

31,117

83.8 (81.1–86.4)

1459

3.7 (1.9–5.6)

 24–27.9 (Overweight)

18,494

94.4 (91.3–97.6)

5609

30.3 (24.8–35.9)

12,885

69.7 (64.1–75.2)

1095

5.6 (2.4–8.7)

  ≥ 28.0 (Obese)

8583

90.8 (84.0–97.6)

4240

49.4 (39.2–59.6)

4343

50.6 (40.4–60.8)

871

9.2 (2.4–16.0)

Altitude level (m)

<  0.001

 Low (2500–3499)

24,892

97.7 (96.0–99.4)

8405

33.8 (28.5–39.0)

16,486

66.2 (61.0–71.5)

585

2.3 (0.6–4.0)

 Middle (3500–4399)

10,082

96.4 (94.9–97.9)

2393

23.7 (18.7–28.8)

7689

76.3 (71.2–81.3)

378

3.6 (2.1–5.1)

 High (4400–5300)

29,252

92.2 (89.0–95.5)

5083

17.4 (13.7–21.0)

24,169

82.6 (79.0–86.3)

2463

7.8 (4.5–11.0)