Table 1 Sociodemographic and health characteristics of participants and care recipients

Demographics

Age (years)

mean ± SD

67.1 ± 9.1

67.3 ± 9.1

67.0 ± 9.2

0.907

61.4 ± 10.2

61.4 ± 10.1

61.4 ± 10.2

0.972

Education (years)

mean ± SD

13.8 ± 2.9

12.8 ± 2.7

14.8 ± 2.7

<0.001

13.4 ± 2.7

12.5 ± 2.2

14.3 ± 2.8

<0.001

Household income

<US$ 50,000; n (%)

41 (48.2)

35 (83.3)

6 (14.0)

< 0.001

108 (54.3)

73 (70.9)

35 (36.5)

< 0.001

Work status

employed; n (%)

41 (46.6)

10 (22.7)

31 (70.5)

< 0.001

81 (39.5)

35 (33.3)

46 (46.0)

0.086

Marital status

single; n (%)

19 (21.6)

15 (34.1)

4 (9.1)

0.008

61 (29.2)

30 (28.6)

31 (29.8)

0.880

Physical conditions

Locomotive syndrome

n (%)

28 (31.8)

16 (36.4)

12 (27.3)

0.493

78 (37.1)

47 (44.8)

31 (29.5)

0.032

BMI (kg/m²)

mean ± SD

23.5 ± 3.2

22.8 ± 3.3

24.3 ± 2.9

0.027

22.4 ± 3.6

22.9 ± 3.7

21.9 ± 3.4

0.037

Menopause

n (%)

-

-

-

-

165 (78.9)

78 (74.3)

87 (83.7)

0.126

Health-related behaviors

Smoking

n (%)

25 (28.4)

15 (34.1)

10 (22.7)

0.345

17 (8.1)

10 (9.5)

7 (6.7)

0.614

Alcohol

n (%)

59 (67.8)

31 (72.1)

28 (63.6)

0.493

86 (41.0)

38 (36.2)

48 (45.7)

0.206

Exercise

n (%)

37 (42.0)

17 (38.6)

20 (45.5)

0.666

68 (32.4)

26 (24.8)

42 (40.0)

0.027

Having annual health check-up

n (%)

62 (73.8)

24 (57.1)

38 (90.5)

0.001

159 (77.9)

70 (67.3)

89 (89.0)

< 0.001

Subjectively-assessed health

Sleep disorder (Pittsburgh Sleep Quality Index)

n (%)

24 (34.3)

14 (34.1)

10 (34.5)

1.000

70 (37.4)

43 (41.7)

27 (32.1)

0.224

Depression (K6)

n (%)

5 (5.9)

1 (2.3)

4 (9.8)

0.192

10 (4.8)

7 (6.7)

3 (2.9)

0.332

Pain (Margolis rating system)

(score range 0–45)

mean ± SD

11.7 ± 6.1

12.6 ± 7.1

10.7 ± 4.7

0.164

14.2 ± 7.8

15.9 ± 8.8

12.4 ± 6.3

<0.001

Indefinite complaint

> 4 syndromes; n (%)

29 (33.0)

16 (36.4)

13 (29.5)

0.651

102 (48.8)

59 (56.2)

43 (41.3)

0.038

Blood pressure

Systolic blood pressure (mmHg)

mean ± SD

135.5 ± 17.4

144.1 ± 15.3

127.0 ± 15.2

<0.001

128.8 ± 20.0

137.7 ± 20.3

119.8 ± 15.2

<0.001

Diastolic blood pressure (mmHg)

mean ± SD

81.5 ± 12.6

86.4 ± 12.9

76.6 ± 10.3

<0.001

77.9 ± 11.9

82.5 ± 12.4

73.4 ± 9.4

<0.001

Serum chemistry

Creatinine (mg/dl)

mean ± SD

0.9 ± 0.2

0.9 ± 0.2

0.9 ± 0.2

0.725

0.7 ± 0.1

0.8 ± 0.1

0.7 ± 0.1

<0.001

Low-density lipoprotein cholesterol (mg/dL)

mean ± SD

112.2 ± 21.6

108.7 ± 20.5

115.7 ± 22.3

0.156

120.2 ± 29.4

119.4 ± 27.7

121.0 ± 31.1

0.370

High-density lipoprotein cholesterol (mg/dL)

mean ± SD

59.8 ± 15.6

64.7 ± 18.1

54.9 ± 10.8

0.014

75.3 ± 17.7

74.8 ± 16.8

75.9 ± 18.5

0.685

Aspartate aminotransferase (IU/L)

mean ± SD

23.1 ± 5.9

23.2 ± 4.3

23.1 ± 7.3

0.372

22.4 ± 7.0

22.3 ± 6.1

22.5 ± 7.7

0.782

Alanine aminotransferase (IU/L)

mean ± SD

21.7 ± 12.5

19.2 ± 9.0

24.3 ± 14.9

0.105

18.2 ± 13.0

16.6 ± 11.9

19.8 ± 13.9

0.004

Gamma-glutamyl transpeptidase (IU/L)

mean ± SD

41.2 ± 57.8

37.7 ± 73.7

44.6 ± 36.0

<0.001

23.6 ± 20.8

19.2 ± 19.7

28.0 ± 21.0

<0.001

Uric acid (mg/dL)

mean ± SD

5.7 ± 1.5

5.0 ± 0.2

6.3 ± 1.2

<0.001

4.6 ± 1.2

4.3 ± 1.2

4.9 ± 1.1

<0.001

Glycosylated hemoglobin (%)

mean ± SD

5.5 ± 0.7

5.4 ± 0.8

5.5 ± 0.6

0.111

5.3 ± 0.6

5.3 ± 0.7

5.3 ± 0.4

0.055

Care recipients

Female

n (%)

42 (95.5)

56 (53.3)

<0.001

Age (years)

mean ± SD

81.2 ± 10.2

82.7 ± 9.9

0.430

ADL score (Barthel Index score)

(score range 0–100)

mean ± SD

34.1 ± 31.4

32.5 ± 30.6

0.687

IADL score; male (score range 0–5)

mean ± SD

0.0

0.9 ± 1.3

0.280

female (score range 0–8)

mean ± SD

1.1 ± 1.5

0.8 ± 1.5

0.170

Certified care level 5 (bed-bound)

n (%)

17 (39.5)

44 (44.9)

0.585

Hours per day caregiving

mean ± SD

11.6 ± 9.0

10.8 ± 7.4

0.883

Duration of caregiving (years)

mean ± SD

5.1 ± 4.9

6.7 ± 5.0

0.057

Copayment of formal caregiving services use under LTCI per month (US$)

mean ± SD

186.1 ± 90.9

209.7 ± 106.9

0.194

Usage rate to the certified maximum allowable services on each care level (%)

mean ± SD

61.2 ± 25.2

65.6 ± 28.4

0.265