Offspring birthweight by gestational age and parental cardiovascular mortality: a population-based cohort study.

OBJECTIVE: To estimate risk of parental cardiovascular disease mortality by offspring birthweight. DESIGN: Population-based cohort study. SETTING AND POPULATION: Norwegian mothers and fathers with singleton births during 1967-2002 were followed until 2009 by linkage to the Norwegian cause of death registry. METHODS: Hazard ratios by offspring absolute birthweight in grams and birthweight adjusted for gestational age (z-score) were calculated using Cox regression and adjusted for parental age at delivery and year of first birth. Stratified analyses on preterm and term births were performed. MAIN OUTCOME MEASURES: Maternal and paternal cardiovascular mortality. RESULTS: We followed 711 726 mothers and 700 212 fathers and found a strong link between maternal cardiovascular mortality and offspring birthweight but only slight evidence of associations in fathers. Adjusting birthweight for gestational age (by z-score) uncovered an unexpected strong association of large birthweight (z-score > 2.5) with mothers' cardiovascular mortality (hazard ratio 3.0, 95% CI 2.0-4.6). This risk was apparently restricted to preterm births. In stratified analyses (preterm and term births) hazard ratios for maternal cardiovascular mortality were 1.5 (1.03-2.2) for large preterm babies and 0.9 (0.7-1.2) for large term babies (P-value for interaction = 0.02), using normal weight preterm and term, respectively, as references. CONCLUSION: Women having large preterm babies are at increased risk of both diabetes and cardiovascular mortality. The birth of a large preterm baby should increase clinical vigilance for onset of diabetes and other cardiovascular disease risk factors. TWEETABLE ABSTRACT: Birth of a large preterm baby should increase vigilance for cardiovascular-disease risk factors.

Tubal ligation in relation to menopausal symptoms and breast cancer risk.

BACKGROUND: Local inflammation after tubal ligation may affect ovarian function and breast cancer risk. METHODS: We analysed tubal ligation, menopausal characteristics, and breast cancer risk in the Sister Study cohort (N=50,884 women). RESULTS: Tubal ligation was associated with hot flashes (hazard ratio (HR) 1.09; 95% confidence interval (CI): 1.06-1.12) but not menopausal age (HR 0.99; 95% CI: 0.96-1.02). Tubal ligation did not have an impact on breast cancer overall (HR 0.95; 95% CI: 0.85-1.06), but had a suggested inverse relation with oestrogen receptor+/progesterone receptor+ invasive tumours (HR 0.84; 95% CI: 0.70-1.01), possibly because of subsequent hysterectomy/bilateral oophorectomy. CONCLUSION: Tubal ligation does not influence overall breast cancer risk.

Employment and work schedule are related to telomere length in women.

OBJECTIVES: To examine the association of employment and work schedule with shorter DNA telomeres, a marker of cellular ageing and disease risk factor, and consider whether differences were related to health, behaviours and sociodemographic factors, or varied by stress levels or menopausal status. METHODS: This cross-sectional analysis of 608 women aged 35-74 in the Sister Study examined determinants of relative telomere length (rTL) measured by quantitative PCR in leucocyte DNA. Age-adjusted regression models estimated base pair (bp) rTL differences for current and lifetime schedule characteristics (ie, part-time, full-time or overtime hours; multiple jobs; irregular hours; shiftwork; work at night). Covariates included race, smoking, perceived stress, sleep, physical activity, health and menopausal status, education, marital status, live births, children under 18, measured body mass index and urinary stress hormones. RESULTS: Compared with non-employed women with moderate or substantial past work histories (n=190), those currently working full-time (n=247; median 40 h/week) had a shorter rTL, an age-adjusted difference of -329 bp (95% CI -110 to -548). Longer-duration full-time work was also associated with shorter rTL (age-adjusted difference of -472 bp, 95% CI -786 to -158 for 20+ vs 1-5 years). Findings were not explained by health and demographic covariates. However, rTL differences for working at least full-time were greater in women with higher stress and epinephrine levels. CONCLUSIONS: Current and long-term full-time work were associated with shorter rTL, with differences of similar magnitude to smoking and history of heart disease or diabetes. Longitudinal data with specific stress measures are needed to further evaluate the impact of work schedule on rTL.

A systematic review of farm safety interventions.

OBJECTIVE: The main objective of this study was to systematically review the existing evidence for the effectiveness of farm injury prevention interventions. SEARCH STRATEGY: We used a systematic approach to search the following electronic databases: MEDLINE, EMBASE, ERIC, PsycInfo, Sociofile, NTIS, Agricola, Expanded Academic Index, Dissertation Abstracts, and Occupational Safety and Health (NIOSHTIC). Proceedings and technical papers of the National Institute for Farm Safety were reviewed. We also checked the references of potentially eligible studies and consulted with experts in the field to identify other relevant information sources. SELECTION CRITERIA: Papers had to involve a farm safety intervention to be included in the review. To best characterize the current state of farm safety research, all study designs were accepted, including those without comparison groups and those with absent or inadequate evaluation methods. RESULTS: We identified 25 studies for the review. Eleven of the studies involved farm safety education programs, five consisted of multifaceted interventions that included environmental revisions, a farm visit, or both; nine papers described farm safety interventions but did not report results from an evaluation. Farm safety education interventions included safety fairs, day camps; certification programs; workshops; and courses for farm families, youth, and agricultural workers. Multifaceted interventions were targeted to farm operators and generally involved farm safety audits, followed by environmental or equipment changes and/or safety education. Program evaluations assessed changes in safety attitudes, knowledge, and/or behaviors and generally involved pre- and post-test methodology. Only three studies examined changes in the incidence of farm injuries. Of the studies evaluated, most reported positive changes following the interventions. However, limitations in the design of evaluations make the results of many of the studies difficult to interpret. CONCLUSIONS: There is a need for more rigorous evaluations of farm safety intervention programs. Suggested study design improvements include randomization of study subjects when appropriate, use of control groups and the objective measurement of outcomes such as behavior change and injury incidence.