Table 3. Relative risk of mortality by the presence of social network member and level of caregiving among 4,530 participants diagnosed with breast cancer from the WHI, 1993–2009.
| Total person- time |
Provide caregiving | No caregiving | Provide caregiving | No caregiving | |||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
|
|
|
|
|
||||||||||
| All-cause death |
HR* | 95% CI | All-cause death |
HR* | 95% CI | Breast cancer death |
HR* | 95% CI | Breast cancer death |
HR* | 95% CI | ||
| Married | |||||||||||||
| No | 11,082 | 50 | 1.00 | 101 | 1.00 | 26 | 1.00 | 42 | 1.00 | ||||
| Yes | 20,101 | 70 | 0.91 | (0.60–1.39) | 133 | 1.04 | (0.77–1.39) | 44 | 0.93 | (0.53–1.65) | 78 | 1.60 | (1.03–2.48) |
| P value | 0.67 | 0.80 | 0.80 | 0.04 | |||||||||
| P-interaction | 0.61 | 0.19 | |||||||||||
| Relatives | |||||||||||||
| 0–3 | 8,519 | 25 | 1.00 | 68 | 1.00 | 10 | 1.00 | 33 | 1.00 | ||||
| 4–5 | 10,450 | 23 | 0.75 | (0.41–1.37) | 74 | 0.88 | (0.62–1.26) | 17 | 1.47 | (0.62–3.52) | 43 | 1.03 | (0.62–1.69) |
| 6–9 | 9,632 | 51 | 1.50 | (0.88–2.57) | 67 | 0.86 | (0.60–1.24) | 29 | 2.08 | (0.89–4.86) | 33 | 0.85 | (0.50–1.44) |
| 10 or more | 2,583 | 21 | 2.06 | (1.06–4.01) | 25 | 0.92 | (0.56–1.52) | 14 | 3.55 | (1.35–9.33) | 11 | 0.79 | (0.37–1.67) |
| P-continuous** | 0.01 | 0.38 | 0.02 | 0.44 | |||||||||
| P-interaction | 0.008 | 0.008 | |||||||||||
| Club participation | |||||||||||||
| No | 13,033 | 49 | 1.00 | 101 | 1.00 | 32 | 1.00 | 57 | 1.00 | ||||
| Yes | 18,150 | 71 | 0.86 | (0.58–1.26) | 133 | 1.13 | (0.87–1.49) | 38 | 0.68 | (0.40–1.16) | 63 | 1.00 | (0.69–1.47) |
| P value | 0.44 | 0.36 | 0.16 | 0.98 | |||||||||
| P-interaction | 0.34 | 0.26 | |||||||||||
| Religious participation | |||||||||||||
| No | 11,452 | 35 | 1.00 | 89 | 1.00 | 20 | 1.00 | 50 | 1.00 | ||||
| Yes | 19,731 | 85 | 1.32 | (0.87–2.02) | 145 | 0.95 | (0.72–1.25) | 50 | 1.56 | (0.87–2.79) | 70 | 0.79 | (0.54–1.16) |
| P value | 0.20 | 0.72 | 0.14 | 0.23 | |||||||||
| P-interaction | 0.23 | 0.08 | |||||||||||
Multivariate-adjusted models adjusted for age, study arm (OS, CT [ref]), time between diagnosis and assessment of social networks, race (white, nonwhite[ref]), income (<$20,000, 20– <50 K, 50–<100 K, $100 K+ [ref]), education (≤HS, >HS-college graduate, post-graduate [ref]), family history of breast cancer (no history [ref], 1 first-degree relative before age 45, 2+ relatives), cancer stage at diagnosis (localized [ref], regional, distant), tumor size (≤3 mm [ref], >3 mm), HER-2 neu status (positive, negative[ref]), nodal status (no involvement [ref], any involvement), estrogen-receptor status (positive, negative [ref]), age at first birth (never pregnant, never had term pregnancy, <20, 20–29, ≥30 years [ref]), smoking status (never [ref], past, current), BMI (<25 [reference] 25–29, 30+ kg/m2), physical activity (<3 [ref], 3–17, 18+ mets/week), comorbidity (yes, no[ref]), mammography within the last two years (yes, no [ref])
P value, continuous variable
Results in bold were statistically significant (P<0.05)