Table 1 Differences in Demographic and Clinical Characteristics Between the Two Age Groups at Enrollment

Age (years)

48.4 (8.5)

68.0 (6.2)

t=-49.06, p < 0.001

Education (years)

16.1 (3.0)

16.3 (3.1)

t=-0.88, p = 0.378

Body mass index (kg/m²)

26.1 (5.7)

26.4 (5.6)

t=-1.14, p = 0.256

Karnofsky Performance Status score

79.0 (12.3)

81.2 (12.6)

t=-3.15, p = 0.002

Number of comorbidities out of 13

2.1 (1.3)

2.8 (1.5)

t=-8.10, p < 0.001

Self-Administered Comorbidity Questionnaire score

5.0 (2.9)

6.1 (3.4)

t=-6.31, p < 0.001

Alcohol Use Disorders Identification Test score

3.0 (2.6)

3.0 (2.4)

t = 0.09, p = 0.929

Time since cancer diagnosis (years)

1.6 (3.1)

2.5 (4.6)

U, p < 0.001

Time since diagnosis (median)

0.40

0.46

Number of prior cancer treatments

1.5 (1.5)

1.7 (1.5)

t=-2.41, p = 0.016

Number of metastatic sites excluding lymph node involvement

0.7 (1.1)

0.9 (1.0)

t=-2.53 p = 0.012

Number of metastatic sites, including lymph node involvement

1.2 (1.3)

1.3 (1.2)

t=-1.86, p = 0.063

MAX2 score

0.18 (0.08)

0.16 (0.08)

t = 5.31, p < 0.001

Number of MSAS symptoms out of 38

14.8 (7.2)

12.9 (7.0)

t = 4.85, p < 0.001

% (n)

% (n)

Female

83.9 (622)

70.2 (422)

FE, p < 0.001

Race/ethnicity

χ² = 51.59, p < 0.001

White

Asian or Pacific Islander

Black

Hispanic, Mixed, or Other

63.2 (461)

17.3 (126)

6.0 (44)

13.6 (99)

77.2 (460)

7.0 (42)

8.6 (51)

7.2 (43)

0 < 1

0 > 1

NS

0 > 1

Married or partnered (% yes)

65.7 (479)

63.0 (375)

FE, p = 0.327

Lives alone (% yes)

17.8 (130)

25.9 (154)

FE, p < 0.001

Childcare responsibilities (% yes)

36.1 (262)

4.8 (28)

FE, p < 0.001

Care of adult responsibilities (% yes)

9.1 (62)

6.5 (35)

FE, p = 0.110

Currently employed (% yes)

42.0 (308)

26.5 (158)

FE, p < 0.001

Annual household income

<$30,000

$30,000 to <$70,000

$70,000 to <$100,000

>$100,000

17.1 (115)

18.9 (127)

16.2 (109)

47.7 (320)

20.0 (106)

24.0 (127)

17.7 (94)

38.3 (203)

U, p = 0.002

Specific comorbidities (% yes)

Heart disease

2.0 (15)

10.3 (62)

FE, p < 0.001

High blood pressure

19.7 (146)

43.2 (260)

FE, p < 0.001

Lung disease

6.5 (48)

17.4 (105)

FE, p < 0.001

Diabetes

5.3 (39)

13.8 (83)

FE, p < 0.001

Ulcer or stomach disease

4.9 (36)

4.8 (29)

FE, p = 1.000

Kidney disease

0.9 (7)

2.0 (12)

FE, p = 0.162

Liver disease

5.8 (43)

7.3 (44)

FE, p = 0.268

Anemia or blood disease

14.7 (109)

9.1 (55)

FE, p = 0.002

Depression

19.4 (144)

18.8 (113)

FE, p = 0.781

Osteoarthritis

6.2 (46)

19.6 (118)

FE, p < 0.001

Back pain

25.5 (189)

26.1 (157)

FE, p = 0.851

Rheumatoid arthritis

2.3 (17)

4.3 (26)

FE, p = 0.042

Exercise on a regular basis (% yes)

74.6 (540)

66.0 (389)

FE, p < 0.001

Current or history of smoking (% yes)

26.3 (192)

46.6 (275)

FE, p < 0.001

Type of cancer

χ² = 93.26, p < 0.001

Breast

Gastrointestinal

Gynecologic

Lung

50.5 (374)

28.2 (209)

15.0 (111)

6.3 (47)

27.6 (166)

33.7 (203)

20.3 (122)

18.4 (111)

0 > 1

0 < 1

0 < 1

0 < 1

Type of prior cancer treatment

χ² = 25.73, p < 0.001

No prior treatment

Only surgery, CTX, or RT

Surgery & CTX, or Surgery & RT, or CTX & RT

Surgery & CTX & RT

27.0 (196)

45.1 (327)

15.0 (109)

12.8 (93)

22.2 (129)

38.3 (222)

25.9 (150)

13.6 (79)

0 > 1

0 > 1

0 < 1

NS

Metastatic sites

χ² = 24.02, p < 0.001

No metastasis

Only lymph nodes

Only non-lymph nodes

Lymph nodes and other sites

36.0 (264)

23.3 (171)

16.6 (122)

24.0 (176)

27.7 (164)

20.5 (121)

26.7 (158)

25.0 (148)

0 > 1

NS

0 < 1

NS

Cycle length

14-day cycle

21-day cycle

28-day cycle

46.8 (341)

48.1 (351)

5.1 (37)

36.3 (217)

53.6 (320)

10.1 (60)

U, p < 0.001

Emetogenicity of the CTX regimen

Minimal/low

Moderate

High

17.4 (127)

58.0 (423)

24.6 (179)

22.1 (132)

64.7 (387)

13.2 (79)

U, p < 0.001

Antiemetic regimen

None

Steroid alone or serotonin antagonist alone

Serotonin antagonist and steroid

NK-1 receptor antagonist and two other antiemetics

6.7 (48)

19.3 138)

46.7 (334)

27.3 (195)

7.6 (44)

21.9 (127)

48.9 (284)

21.7 (126)

χ² = 5.71, p = 0.126