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BACKGROUND: Recent evidence suggests that higher levels of residential greenness may contribute to better mental health. Despite this, few studies have considered its impact on depression, and most are cross-sectional. OBJECTIVE: The objective of this study was to examine surrounding residential greenness and depression risk prospectively in the Nurses' Health Study. METHODS: A total of 38,947 women (mean age throughout follow-up 70 y [range 54-91 y]) without depression in 2000 were followed to 2010. Residential greenness was measured using the satellite-based Normalized Difference Vegetation Index (NDVI) and defined as the mean greenness value within [Formula: see text] and [Formula: see text] radii of the women's residences in July of each year. Incidence of depression was defined according to the first self-report of either physician-diagnosed depression or regular antidepressant use. We used Cox proportional hazards models to examine the relationship between greenness and depression incidence and assessed physical activity as a potential effect modifier and mediator. RESULTS: Over 315,548 person-years, 3,612 incident depression cases occurred. In multivariable-adjusted models, living in the highest quintile of residential greenness within [Formula: see text] was associated with a 13% reduction in depression risk ([Formula: see text] [95% confidence interval (CI): 0.78, 0.98]) compared with the lowest quintile. The association between greenness and depression did not appear to be mediated by physical activity, nor was there evidence of effect modification by physical activity. CONCLUSIONS: In this population of mostly white women, we estimated an inverse association between the highest level of surrounding summer greenness and the risk of self-reported depression. [ABSTRACT FROM AUTHOR]

The article discusses the 40th anniversary of the Nurses' Health Study (NHS) as of 2016 in relation to the author's views about public health interventions and methods for eliminating bias that is attributable to measurement error and misclassification. Controversies involving longitudinal cohort studies that use food frequency questionnaires to assess dietary intake over time are examined, along with various American epidemiological research methodologies.

Background: Plant-based diets have been recommended to reduce the risk of type 2 diabetes (T2D). However, not all plant foods are necessarily beneficial. We examined the association of an overall plant-based diet and hypothesized healthful and unhealthful versions of a plant-based diet with T2D incidence in three prospective cohort studies in the US.Methods and Findings: We included 69,949 women from the Nurses' Health Study (1984-2012), 90,239 women from the Nurses' Health Study 2 (1991-2011), and 40,539 men from the Health Professionals Follow-Up Study (1986-2010), free of chronic diseases at baseline. Dietary data were collected every 2-4 y using a semi-quantitative food frequency questionnaire. Using these data, we created an overall plant-based diet index (PDI), where plant foods received positive scores, while animal foods (animal fats, dairy, eggs, fish/seafood, poultry/red meat, miscellaneous animal-based foods) received reverse scores. We also created a healthful plant-based diet index (hPDI), where healthy plant foods (whole grains, fruits, vegetables, nuts, legumes, vegetable oils, tea/coffee) received positive scores, while less healthy plant foods (fruit juices, sweetened beverages, refined grains, potatoes, sweets/desserts) and animal foods received reverse scores. Lastly, we created an unhealthful plant-based diet index (uPDI) by assigning positive scores to less healthy plant foods and reverse scores to healthy plant foods and animal foods. We documented 16,162 incident T2D cases during 4,102,369 person-years of follow-up. In pooled multivariable-adjusted analysis, both PDI and hPDI were inversely associated with T2D (PDI: hazard ratio [HR] for extreme deciles 0.51, 95% CI 0.47-0.55, p trend < 0.001; hPDI: HR for extreme deciles 0.55, 95% CI 0.51-0.59, p trend < 0.001). The association of T2D with PDI was considerably attenuated when we additionally adjusted for body mass index (BMI) categories (HR 0.80, 95% CI 0.74-0.87, p trend < 0.001), while that with hPDI remained largely unchanged (HR 0.66, 95% CI 0.61-0.72, p trend < 0.001). uPDI was positively associated with T2D even after BMI adjustment (HR for extreme deciles 1.16, 95% CI 1.08-1.25, p trend < 0.001). Limitations of the study include self-reported diet assessment, with the possibility of measurement error, and the potential for residual or unmeasured confounding given the observational nature of the study design.Conclusions: Our study suggests that plant-based diets, especially when rich in high-quality plant foods, are associated with substantially lower risk of developing T2D. This supports current recommendations to shift to diets rich in healthy plant foods, with lower intake of less healthy plant and animal foods. [ABSTRACT FROM AUTHOR]

Background: Although obesity has been linked to an increased risk of colorectal cancer (CRC), the risk associated with long-term status or change of body fat distribution has not been fully elucidated.Methods: Using repeated anthropometric assessments in the Nurses' Health Study and Health Professionals Follow-up Study, we prospectively investigated cumulative average waist circumference, hip circumference and waist-to-hip ratio, as well as their 10-year changes over adulthood, in relation to CRC risk over 23-24 years of follow-up. Cox proportional hazards models were used to calculate the hazard ratio (HR) and 95% confidence interval (CI).Results: High waist circumference, hip circumference and waist-to-hip ratio were all associated with a higher CRC risk in men, even after adjusting for body mass index. The association was attenuated to null in women after adjusting for body mass index. Ten-year gain of waist circumference was positively associated with CRC risk in men (P for trend = 0.03), but not in women (P for trend = 0.34).Compared with men maintaining their waist circumference, those gaining waist circumference by ≥ 10 cm were at a higher risk of CRC, with a multivariable-adjusted HR of 1.59 (95% CI, 1.01-2.49). This association appeared to be independent of weight change.Conclusions: Abdominal adiposity, independent of overall obesity, is associated with an increased CRC risk in men but not in women. Our findings also provide the first prospective evidence that waist circumference gain during adulthood may be associated with higher CRC risk in men, thus highlighting the importance of maintaining a healthy waist for CRC prevention. [ABSTRACT FROM AUTHOR]

Background: Endometriosis is a prevalent gynecologic disease associated with systemic chronic inflammation, heightened oxidative stress, and atherogenic lipid profile that may increase women's risk for coronary heart disease (CHD).Methods and Results: We examined the prospective association between laparoscopically confirmed endometriosis and subsequent CHD among 116 430 women in the Nurses' Health Study II (1989-2009). Participants with a history of heart disease and stroke were excluded. When compared with women without endometriosis, women with laparoscopically confirmed endometriosis had a higher risk of myocardial infarction (relative risk, 1.52; 95% confidence interval, 1.17-1.98), angiographically confirmed angina (1.91; 1.59-2.29), coronary artery bypass graft surgery/coronary angioplasty procedure/stent (1.35; 1.08-1.69), or any of these CHD end points combined (1.62; 1.39-1.89), independent of potential demographic, anthropometric, family history, reproductive, and lifestyle confounders. Relative risk for the combined CHD end point was highest among women aged ≤40 years (3.08; 2.02-4.70) and decreased as age increased (40< age ≤50 years, 1.65; 1.35-2.02; 50< age ≤55 years, 1.44; 1.07-1.94; and age >55 years, 0.98; 0.56-1.72; P value, test for heterogeneity=0.001). Having had a hysterectomy/oophorectomy was associated with higher risk of combined CHD compared with not having had a hysterectomy/oophorectomy (1.51; 1.34-1.71). A percentage of 42 of the association between endometriosis and CHD could be explained by greater frequency of hysterectomy/oophorectomy and earlier age at surgery after endometriosis diagnosis.Conclusions: In this large, prospective cohort, laparoscopically confirmed endometriosis was associated with increased risk of CHD. The association was strongest among young women. Hysterectomy/oophorectomy was associated with higher risk of CHD and could partially explain the association between endometriosis and CHD. [ABSTRACT FROM AUTHOR]

Background: Prospective data on the relation of magnesium, potassium, and calcium intakes with stroke risk are inconsistent, and to our knowledge, the effect of a combined mineral diet score has not been examined. Objective: We examined associations between intakes of magnesium, potassium, and calcium and risk of incident stroke in 86,149 women in the Nurses' Health Study (NHS) I and 94,715 women in the NHS II. Design: In this prospective cohort study, we calculated HRs of stroke by quintiles of intake for each mineral and for a combined diet score of all 3 minerals by using multivariate Cox proportional hazard models. In addition, we updated meta-analyses on dietary intakes of these minerals and risk of stroke. Results: During follow-up (30 y in the NHS I; 22 y in the NHS II) a total of 3780 incident stroke cases were documented. Pooled multivariate RRs of total stroke for women in the highest compared with the lowest quintiles were 0.87 (95% CI: 0.78, 0.97) for total magnesium, 0.89 (95% CI: 0.80, 0.99) for total potassium, and 0.97 (95% CI: 0.87, 1.09) for total calcium intake. Pooled RRs for women in the highest compared with the lowest quintiles of a combined mineral diet score were 0.72 (95% CI: 0.65, 0.81) for total stroke, 0.78 (95% CI: 0.66, 0.92) for ischemic stroke, and 0.80 (95% CI: 0.61, 1.04) for hemorrhagic stroke. In the updated meta-analyses of all prospective studies to date, the combined RR of total stroke was 0.87 (95% CI: 0.83, 0.92) for a 100-mg/d increase in magnesium intake, 0.91 (95% CI: 0.88, 0.94) for a 1000-mg/d increase in potassium intake, and 0.98 (95% CI: 0.94, 1.02) for a 300-mg/d increase in calcium intake. Conclusions: A combined mineral diet score was inversely associated with risk of stroke. High intakes of magnesium and potassium but not calcium were also significantly associated with reduced risk of stroke in women. [ABSTRACT FROM AUTHOR]

Objectives. To compare changes in self-reported sexual orientation of women living in states with any recognition of same-sex relationships (e.g., hospital visitation, domestic partnerships) with those of women living in states without such recognition. Methods. We calculated the likelihood of women in the Nurses' Health Study II (n = 69 790) changing their reported sexual orientation between 1995 and 2009. Results. We used data from the Nurses' Health Study II and found that living in a state with same-sex relationship recognition was associated with changing one's reported sexual orientation, particularly from heterosexual to sexual minority. Individuals who reported being heterosexual in 1995 were 30% more likely to report a minority orientation (i.e., bisexual or lesbian) in 2009 (risk ratio = 1.30; 95% confidence interval = 1.05, 1.61) if they lived in a state with any recognition of same-sex relationships compared with those who lived in a state without such recognition. Conclusions. Policies recognizing same-sex relationships may encourage women to report a sexual minority orientation. Future research is needed to clarify how other social and legal policies may affect sexual orientation self-reports. [ABSTRACT FROM AUTHOR]

Background: A body of literature has suggested an elevated risk of lung cancer associated with particulate matter and traffic-related pollutants. Objective: We examined the relation of lung cancer incidence with long-term residential exposures to ambient particulate matter and residential distance to roadway, as a proxy for traffic-related exposures. Methods: For participants in the Nurses’ Health Study, a nationwide prospective cohort of women, we estimated 72‑month average exposures to PM2.5, PM2.5–10, and PM10 and residential distance to road. Follow-up for incident cases of lung cancer occurred from 1994 through 2010. Cox proportional hazards models were adjusted for potential confounders. Effect modification by smoking status was examined. Results: During 1,510,027 person-years, 2,155 incident cases of lung cancer were observed among 103,650 participants. In fully adjusted models, a 10‑μg/m3 increase in 72‑month average PM10 [hazard ratio (HR) = 1.04; 95% CI: 0.95, 1.14], PM2.5 (HR = 1.06; 95% CI: 0.91, 1.25), or PM2.5-10 (HR = 1.05; 95% CI: 0.92, 1.20) was positively associated with lung cancer. When the cohort was restricted to never-smokers and to former smokers who had quit at least 10 years before, the associations appeared to increase and were strongest for PM2.5 (PM10: HR = 1.15; 95% CI: 1.00, 1.32; PM2.5: HR = 1.37; 95% CI: 1.06, 1.77; PM2.5-10: HR = 1.11; 95% CI: 0.90, 1.37). Results were most elevated when restricted to the most prevalent subtype, adenocarcinomas. Risks with roadway proximity were less consistent. Conclusions: Our findings support those from other studies indicating increased risk of incident lung cancer associated with ambient PM exposures, especially among never- and long-term former smokers. [ABSTRACT FROM AUTHOR]

Objectives. We investigated associations of smoking and coronary heart disease (CHD) by age. Methods. Data came from the Pooling Project on Diet and Coronary Heart Disease (8 prospective studies, 1974-1996; n = 192 067 women and 74 720 men, aged 40-89 years). Results. During follow-up, 4326 cases of CHD were reported. Relative to never smokers, CHD risk among current smokers was highest in the youngest and lowest in the oldest participants. For example, among women aged 40 to 49 years the hazard ratio was 8.5 (95% confidence interval [CI] = 5.0, 14) and 3.1 (95% CI = 2.0, 4.9) among those aged 70 years or older. The largest absolute risk differences between current smokers and never smokers were observed among the oldest participants. Finally, the majority of CHD cases among smokers were attributable to smoking. For example, attributable proportions of CHD by age group were 88% (40-49 years), 81% (50-59 years), 71% for (60-69 years), and 68% (‡ 70 years) among women who smoked. Conclusions. Among smokers, the majority of CHD cases are attributable to smoking in all age groups. Smoking prevention is important, irrespective of age. [ABSTRACT FROM AUTHOR]

Aspirin use decreases colon cancer risk, but this association may vary among population subgroups. The aspirin-colon cancer association was evaluated according to body mass index and physical activity in 1,701 incident colon cancer cases diagnosed during follow-up of 139,310 participants for up to 26 years in 2 US prospective cohort studies that began in 1980 and 1992, respectively. Whether plasma C-peptide levels modified the association was examined by using a nested case-control design (n = 384 cases, 749 controls). Multiplicative and additive interactions were tested. Body mass index did not modify the association; pooled multivariable relative risks for regular aspirin use versus nonuse ranged from 0.74 to 0.75 in the normal weight and obese groups (test for multiplicative interaction, P = 0.75; test for additive interaction, P = 0.66). Pooled multivariable relative risks for regular aspirin use were 0.86 (95% confidence interval (CI): 0.66, 1.11) in the low and 0.67 (95% CI: 0.58, 0.77) in the high physical activity groups with no interaction evident on either the multiplicative or additive scale (P > 0.10). Plasma C-peptide levels also did not modify the aspirin-colon cancer association, with multivariable relative risks of 0.74 (95% CI: 0.50, 1.10) for the low and 0.65 (95% CI: 0.46, 0.92) for the high group. Reductions in colon cancer risk associated with aspirin use were not significantly modified by body mass index, physical activity, or plasma C-peptide level in this study. [ABSTRACT FROM AUTHOR]

Background: Environmental exposure to polychlorinated biphenyls (PCBs) and p,p'-dichlorodiphenyldichloroethylene (p, p'-DDE) has been associated with the risk of non-Hodgkin lymphoma.Methods: We conducted a case-control study nested within the Physicians' Health Study, a prospective cohort established in 1982. We measured concentrations of PCBs and p,p'-DDE in baseline blood samples from 205 men later diagnosed with non-Hodgkin lymphoma and 409 age- and race-matched controls. Lipid-adjusted organochlorine concentrations were categorized into quintiles based on the distribution among controls. We used conditional logistic regression to estimate the odds ratios (ORs) and 95% confidence intervals (CIs) for each quintile relative to the lowest quintile. We also evaluated these associations for major histologic subtypes of non-Hodgkin lymphoma.Results: The risk of non-Hodgkin lymphoma was positively associated with the sum of 51 PCB congeners assayed (SigmaPCB); the group of immunotoxic congeners; the individual congeners 118, 138, 153, and 180; and the sum of these 4 congeners. The simple OR for the highest quintile of lipid-adjusted SigmaPCB versus the lowest was 1.9 (95% CI = 1.1-3.2; test for trend, P = 0.001), with similar trends for individual congeners and groups defined as above. Adjustment for height, body mass index, alcohol intake, smoking, and fish intake did not substantially change the effect estimates. No association was observed for p,p'-DDE. There was no evidence of statistical heterogeneity in effects by histologic subtype of lymphoma; however, this analysis was underpowered.Conclusions: These results support the hypothesis of a positive association between PCB exposure and development of NHL in men. [ABSTRACT FROM AUTHOR]

Background: A potential role of prenatal and perinatal exposures in autoimmunity has been hypothesized, but few studies have examined the relation between various prenatal and perinatal factors and the risk of multiple sclerosis (MS).Methods: The study population included participants in the Nurses' Health Studies--2 prospective cohorts that together comprise 238,381 female nurses, who self-reported exposure to prenatal and perinatal factors. In addition, 35,815 nurses' mothers participated by providing detailed information regarding experiences surrounding their daughter's birth. The following prenatal and perinatal factors were studied in relation to MS: fetal growth, birth season, preterm birth, mode of delivery, maternal weight gain, medical conditions, medication use, diethylstilbestrol exposure, prenatal health care, maternal activity level, maternal obstetric history, parental age, and prenatal and childhood passive smoke exposure.Results: The sample included 723 confirmed MS cases, including 383 with diagnosis after reporting prenatal and perinatal factors. Few associations were observed. These included an increased risk among women whose mothers reported late initiation of prenatal care (after the first trimester) (27 cases; rate ratio = 1.6 [95% confidence interval = 1.0-2.4]), diabetes during pregnancy (2 cases; 10 [2.5-42]), and maternal prepregnancy overweight/obesity (20 cases; 1.7 [1.0-2.7]). Results also suggested a possible increase in incident MS risk among women with prenatal diethylstilbestrol exposure (9 cases; 1.8 [0.93-3.5]).Conclusions: This study provides modest support for a role of prenatal factors in MS risk. The results should be interpreted cautiously due to the limited statistical power, potential for exposure misclassification, and possibility of chance findings. [ABSTRACT FROM AUTHOR]

Background: Uterine leiomyomata are a major source of morbidity in black women. We prospectively investigated the risk of self-reported uterine leiomyomata in relation to body mass index (BMI), weight change, height, waist and hip circumferences, and waist-to-hip ratio in a large cohort of U.S black women.Methods: Data were derived from the Black Women's Health Study, a U.S. prospective cohort study of black women who complete biannual mailed health questionnaires. From 1997 through 2001, we followed 21,506 premenopausal women with intact uteri and no prior diagnosis of uterine leiomyomata. Cox regression models were used to estimate incidence rate ratios (IRRs) and 95% confidence intervals (CIs).Results: After 70,345 person-years of follow up, 2146 new cases of uterine leiomyomata confirmed by ultrasound (n = 1885) or hysterectomy (n = 261) were self-reported. Compared with the thinnest women (BMI <20.0 kg/m), the multivariate IRRs for women with BMIs of 20.0-22.4, 22.5-24.9, 25.0-27.4, 27.5-29.9, 30.0-32.4, and 32.5+ kg/m were 1.34 (95% CI = 1.02-1.75), 1.39 (1.07-1.81), 1.45 (1.12-1.89), 1.47 (1.11-1.93), 1.36 (1.02-1.80), and 1.21 (0.93-1.58), respectively. IRRs were larger among parous women. Weight gain since age 18 was positively associated with risk, but only among parous women. No other anthropometric measures were associated with risk.Conclusions: BMI and weight gain exhibited a complex relation with risk of uterine leiomyomata in the Black Women's Health Study. The BMI association was inverse J-shaped and findings were stronger in parous women. Weight gain was positively associated with risk among parous women only. [ABSTRACT FROM AUTHOR]

Background: Plant-based diets are recommended for coronary heart disease (CHD) prevention. However, not all plant foods are necessarily beneficial for health.Objectives: This study sought to examine associations between plant-based diet indices and CHD incidence.Methods: We included 73,710 women in NHS (Nurses' Health Study) (1984 to 2012), 92,329 women in NHS2 (1991 to 2013), and 43,259 men in Health Professionals Follow-up Study (1986 to 2012), free of chronic diseases at baseline. We created an overall plant-based diet index (PDI) from repeated semiquantitative food-frequency questionnaire data, by assigning positive scores to plant foods and reverse scores to animal foods. We also created a healthful plant-based diet index (hPDI) where healthy plant foods (whole grains, fruits/vegetables, nuts/legumes, oils, tea/coffee) received positive scores, whereas less-healthy plant foods (juices/sweetened beverages, refined grains, potatoes/fries, sweets) and animal foods received reverse scores. To create an unhealthful PDI (uPDI), we gave positive scores to less-healthy plant foods and reverse scores to animal and healthy plant foods.Results: Over 4,833,042 person-years of follow-up, we documented 8,631 incident CHD cases. In pooled multivariable analysis, higher adherence to PDI was independently inversely associated with CHD (hazard ratio [HR] comparing extreme deciles: 0.92; 95% confidence interval [CI]: 0.83 to 1.01; p trend = 0.003). This inverse association was stronger for hDPI (HR: 0.75; 95% CI: 0.68 to 0.83; p trend <0.001). Conversely, uPDI was positively associated with CHD (HR: 1.32; 95% CI: 1.20 to 1.46; p trend <0.001).Conclusions: Higher intake of a plant-based diet index rich in healthier plant foods is associated with substantially lower CHD risk, whereas a plant-based diet index that emphasizes less-healthy plant foods is associated with higher CHD risk. [ABSTRACT FROM AUTHOR]

OBJECTIVES: Young women who are sexual minorities (eg, bisexual and lesbian) are approximately twice as likely as those who are heterosexual to have a teen pregnancy. Therefore, we hypothesized that risk factors for teen pregnancy would vary across sexual orientation groups and that other potential risk factors exist that are unique to sexual minorities. METHODS: We used multivariable log-binomial models gathered from 7120 young women in the longitudinal cohort known as the Growing Up Today Study to examine the following potential teen pregnancy risk factors: childhood maltreatment, bullying victimization and perpetration, and gender nonconformity. Among sexual minorities, we also examined the following: sexual minority developmental milestones, sexual orientation-related stress, sexual minority outness, and lesbian, gay, and bisexual social activity involvement. RESULTS: Childhood maltreatment and bullying were significant teen pregnancy risk factors among all participants. After adjusting for childhood maltreatment and bullying, the sexual orientation-related teen pregnancy disparities were attenuated; these risk factors explained 45% of the disparity. Among sexual minorities, reaching sexual minority developmental milestones earlier was also associated with an increased teen pregnancy risk. CONCLUSIONS: The higher teen pregnancy prevalence among sexual minorities compared with heterosexuals in this cohort was partially explained by childhood maltreatment and bullying, which may, in part, stem from sexual orientation-related discrimination. Teen pregnancy prevention efforts that are focused on risk factors more common among young women who are sexual minorities (eg, childhood maltreatment, bullying) can help to reduce the existing sexual orientation-related teen pregnancy disparity. [ABSTRACT FROM AUTHOR]