Table 1 Basic characteristics of participants in the baseline survey in winter

Location

Region

< 0.001

 Hokkaido region

73 (5)

37 (16)

32 (3)

4 (1)

 Tohoku region

156 (11)

15 (6)

78 (8)

63 (20)

 Kanto region

280 (19)

60 (25)

173 (19)

47 (15)

 Chubu region

305 (21)

38 (16)

200 (22)

67 (21)

 Kinki region

297 (20)

48 (20)

194 (21)

55 (17)

 Chugoku region

98 (7)

14 (6)

58 (6)

26 (8)

 Shikoku region

69 (5)

14 (6)

44 (5)

11 (3)

 Kyushu region

202 (14)

12 (5)

145 (16)

45 (14)

Demographics

 Age (≥ 65 years)

352 (24)

44 (18)

222 (24)

86 (27)

0.061

 Men

816

136 (57)

518 (56)

162 (51)

0.227

 Body mass index (≥ 25 kg/m²)

318 (21)

53

197 (21)

68 (21)

0.950

 Household income

0.007

  Low (< 2 million JPY)

105 (8)

12 (6)

62 (7)

31 (10)

  Middle (2−6 million JPY)

647 (47)

105 (48)

384 (45)

158 (53)

  High (≥ 6 million JPY)

616 (45)

101 (46)

407 (48)

108 (36)

Lifestyle

 Salt check sheet

0.617

  Low (0−8 points)

180 (13)

28 (12)

109 (12)

43 (14)

  Medium (9−13 points)

566 (40)

101 (44)

357 (41)

108 (36)

  High (14−19 points)

555 (39)

84 (36)

349 (40)

122 (41)

  Very high (≥20 points)

112 (8)

18 (8)

66 (7)

28 (9)

 Regular vegetable intake

1111 (75)

179 (75)

687 (75)

245 (77)

0.716

 Regular exercise

441 (30)

66 (28)

255 (28)

120 (38)

0.003

 Current smoker

224 (16)

40 (18)

138 (16)

46 (16)

0.803

 Current drinker

872 (60)

141 (60)

568 (62)

163 (52)

0.005

 Antihypertensive drug use

325 (23)

35 (15)

212 (24)

78 (25)

0.007

Health condition

 Stroke

17 (1)

4 (2)

9 (1)

4 (1)

0.649

 Angina/Myocardial infarction

35 (2)

5 (2)

22 (2)

8 (3)

0.944

 Diabetes

87 (6)

14 (6)

59 (7)

14 (5)

0.452

 Hyperlipidemia

259 (18)

31 (13)

167 (19)

61 (20)

0.107

 Hypertension

312 (22)

31 (13)

207 (23)

74 (24)

0.003