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Background Epidemiological evidence suggests that inadequate sleep duration and insomnia may be associated with increased risk of metabolic syndrome (MetS). However, longitudinal data with repeated measures of sleep duration and insomnia and of MetS are limited. We examined the association of sleep duration and insomnia with MetS and its components using longitudinal data from the Women’s Health Initiative (WHI). Methods The study included postmenopausal women (ages 50–79 years) diabetes-free at enrollment in the WHI, with baseline data on sleep duration (n = 5,159), insomnia (n = 5,063), MetS, and its components. Repeated measures of self-reported sleep duration and insomnia were available from years 1 or 3 of follow-up and of the MetS components from years 3, 6 and 9. Associations were assessed using logistic regression and generalized estimating equations models, and odds ratios and 95% confidence intervals (CI) adjusted for major risk factors were calculated. Results In cross-sectional analysis, baseline sleep duration ≥ 9 h was positively associated with MetS (OR = 1.51; 95%CI 1.12–2.04), while sleep duration of 8- 88 cm and triglycerides ≥ 150 mg/dL (OR = 1.18; 95%CI 1.01–1.40 and OR = 1.23; 95%CI 1.05–1.46, respectively). Insomnia had a borderline positive association with MetS (OR = 1.14; 95%CI 0.99–1.31), and significant positive associations with waist circumference > 88 cm and glucose ≥ 100 mg/dL (OR = 1.18; 95%CI 1.03–1.34 and OR = 1.17; 95%CI 1.02–1.35, respectively). In the longitudinal analysis, change from restful sleep to insomnia over time was associated with increased odds of developing MetS (OR = 1.40; 95%CI 1.01–1.94), and of a triglyceride level ≥ 150 mg/dL (OR = 1.48; 95%CI 1.08–2.03). Conclusions Among postmenopausal women in the WHI, sleep duration and insomnia were associated with current and future risk of MetS and some of its components.

Additional file 1: Supplementary Table 1. Frequency of sleep duration and insomnia and metabolic syndrome at baseline and follow-up exams. Supplementary table 2. Cross-sectional analysis of sleep duration with metabolic syndrome and its components using logistic regression models and sleep duration 7

Studies of obesity and survival among patients with breast cancer produce conflicting results, possibly because of heterogeneity by molecular subtype.This study examined whether the association of body mass index (BMI) at diagnosis with breast cancer recurrence and survival varied across subtypes defined by PAM50 (Prediction Analysis of Microarray 50) gene expression. Included were 1559 Kaiser Permanente Northern California members ages 18 to 79 years who had PAM50 assays and were diagnosed with American Joint Committee on Cancer stage I through III breast cancer from 1996 to 2013. Patients reported weight and height. Cox regression models were adjusted for age, menopause, race/ethnicity, stage, and chemotherapy.Over a median of 9 years (maximum, 19 years), 378 women developed recurrent disease, and 312 died from breast cancer. Overall, BMI was not associated with breast cancer recurrence or survival when controlling for subtype (eg, the hazard ratio per 5 kg/mAmong patients who had accurately classified breast cancer subtypes based on gene expression, a BMI ≥35 kg/m