Purpose

Lifestyle factors such as smoking, alcohol, body weight, physical activity, and diet quality have been associated with the risk of pancreatic cancer. However, studies of their combined association in women are limited.

Methods

Data on smoking habits, alcohol intake, diet composition, recreational physical activity, body weight, and waist circumference, obtained at recruitment for 136,945 postmenopausal women (aged 50-79 years) participating in the Women's Health Initiative study, were categorized separately, with higher scores for each variable assigned to the categories representing healthier behaviors. The combined healthy lifestyle index (HLI) score, created by summing the scores for each risk factor, was grouped into quartiles. We used multivariable-adjusted Cox regression to estimate hazard ratios (HR) and 95% confidence intervals (CI) for pancreatic cancer risk in association with the HLI.

Results

Over an average follow-up period of approximately 16.0 years, 1,119 incident cases of pancreatic cancer were ascertained. Compared to women in the lowest HLI quartile, those in the upper quartiles (qt) had a reduced risk of pancreatic cancer (multivariable-adjusted HRqt₃^rd 0.83, 95% CI 0.74-0.99; and HRqt₄^th 0.74, 95% CI 0.62-0.88, respectively, p trend = 0.001). Use of waist circumference instead of BMI in the HLI score yielded similar results. Among women who were either non-diabetic or non-smokers, high HLI was also associated with reduced risk (HRqt₄^th 0.78, 95% CI 0.65-0.85 and HRqt₄^th 0.80, 95% CI 0.66-0.97, respectively). Stratification by BMI categories (18.5- < 25.0, 25.0- < 30.0 and > 30.0 kg/m²) showed similar results in all groups.

Conclusions

Our findings suggest that in postmenopausal women, a healthy lifestyle is associated with reduced risk of pancreatic cancer.

Introduction

Physical activity can attenuate cancer-related declines in physical functioning, improve emotional well-being, and prolong survival among older (≥65 years) breast cancer survivors. However, factors associated with physical activity among older breast cancer survivors are not well-understood.

Materials and methods

Participants were enrolled in the Women's Health Initiative (WHI) Life and Longevity After Cancer (LILAC) study. Descriptive statistics, multiple linear regression, and relative risk [RR] regression were used to assess the association of demographic, clinical, physical and psychosocial variables with the total duration of and participation in physical activity among postmenopausal breast cancer survivors. Age-specific correlates (65-74 years vs. 75-84 years vs. ≥85 years) of physical activity were also examined.

Results

The majority of participants (n = 3710, mean age = 78.8 ± 5.9) were white (90.7%) and had in situ/localized breast cancer (78.9%). Women who had higher education (RR = 1.47 for graduate/professional school versus high school or less, 95% CI: 1.32, 1.63), higher self-rated health (RR = 1.04 for 10 point increase, 95% CI:1.02, 1.07), higher physical functioning (RR = 1.03 for 5 point increase, 95% CI: 1.02, 1.04), and higher social support (RR = 1.41 for social support all of the time versus none of the time, 95% CI: 1.01, 1.96), were more likely to engage in any physical activity. Similar results were observed for duration of physical activity. Among women aged <75, radiation therapy, but not chemotherapy, was associated with longer duration of total physical activity (adjusted difference = 19.7 min/week, 95% CI: 6.1, 33.3), but was not associated with duration among older women. The association between pain and duration of moderate/strenuous activity also differed with age: among women aged <75, those with moderate pain averaged fewer minutes of moderate/strenuous physical activity than those with no pain (adjusted difference:-14.4 min/week, 95% CI:-28.5, -0.1). However, among women aged ≥85, those with moderate pain averaged more minutes of moderate/strenuous physical activity per week than those with no pain (adjusted difference:16.6 min/week; 95% CI:2.9, 30.3).

Discussion

Multiple factors were associated with physical activity among older breast cancer survivors in the WHI. Future physical activity interventions should focus on age-related (e.g., comorbidities) and treatment-related factors (e.g., radiation) as well as certain subgroups, such as women with higher symptom burden.