Aims To explore sex-specific associations between long-term individual blood pressure (BP) patterns and risk of incident atrial fibrillation (AF) in the general population. Methods and results Blood pressure was measured in 8376 women and 7670 men who attended at least two of the three population-based Tromsø Study surveys conducted in 1986–87, 1994–95, and 2001. Participants were followed for incident AF throughout 2013. Latent mixed modelling was used to identify long-term trajectories of systolic BP and hypertension. Cox regression was used to estimate associations between the identified trajectories and incident AF. Elevated systolic BP throughout the exposure period (1986–2001) independently and differentially increased risk of AF in women and men. In women, having elevated systolic BP trajectories doubled AF risk compared to having persistently low levels, irrespective of whether systolic BP increased, decreased, or was persistently high over time, with hazard ratios of 1.88 (95% confidence interval 1.37–2.58), 2.32 (1.61–3.35), and 1.94 (1.28–2.94), respectively. In men, those with elevated systolic BP that continued to increase over time had a 50% increased AF risk: 1.51 (1.09–2.10). When compared to those persistently normotensive, women developing hypertension during the exposure period, and women and men with hypertension throughout the exposure period had 1.40 (1.06–1.86), 2.75 (1.99–3.80), and 1.36 (1.10–1.68) times increased risk of AF, respectively. Conclusion Long-term BP and hypertension trajectories were associated with increased incidence of AF in both women and men, but the associations were stronger in women.

RHR is an independent risk factor for several cardiovascular events. A novel finding is the positive association between RHR and AF in men and the sex difference in association with ischaemic stroke.

BackgroundInternational studies on the association between maternal body mass index (BMI) and spontaneous preterm birth (PTB) yield controversial results warranting large studies from other settings. The aim of this article was to study association between maternal early pregnancy BMI and the risk of spontaneous PTB in Murmansk County (MC), Northwest Russia.MethodsThis is a registry-based cohort study. All women with singleton pregnancies registered at antenatal clinics during the first 12 weeks of gestation and who delivered in MC between January, 1st 2006 and December, 31st 2011 comprised the study base (n = 29,709). All women were categorized by BMI into four groups: underweight (<18.5 kg/m2), normal (18.5–24.9 kg/m2), overweight (25.0–29.9 kg/m2), and obese (≥30.0 kg/m2). Multivariable logistic regression was used to study associations between maternal BMI and PTB (<37 weeks) and very preterm birth (VPTB) (<32 weeks) adjusted for socio-economic factors, biological and lifestyle characteristics.ResultsThe prevalence of underweight, overweight and obesity were 7.1% (95% CI: 6.8-7.4), 18.3% (95% CI: 17.8-18.7) and 7.1% (95% CI: 6.8-7.4), respectively. Altogether, 5.5% (95% CI: 5.3-5.8) of the births were PTB and 0.8% (95% CI: 0.7-0.9) were VPTB. After adjustment, both underweight (OR = 1.25, 95% CI: 1.03-1.50), overweight (OR = 1.10, 95% CI: 0.97-1.26) and obese (OR = 1.31, 95% CI: 1.08-1.57) women were more likely to deliver preterm. VPTB was associated with overweight (OR = 1.47, 95% CI: 1.056-2.03) and obesity (OR = 1.63, 95% CI: 1.02-2.60).ConclusionThe findings demonstrate a J-shaped association between first trimester maternal BMI and spontaneous PTB and VPTB with increased risk among underweight, overweight and obese women.

Background Resting heart rate is an established risk factor for cardiovascular disease, but long-term individual resting heart rate trajectories and their effect on cardiovascular disease morbidity and mortality have not yet been described. Methods This large population-based longitudinal study included 14,208 men and women aged 20 years or older, not pregnant and not using blood pressure medications, who attended at least two of the three Tromsø Study surveys conducted between 1986-2001. Resting heart rate was measured using an automated Dinamap device. Participants were followed up from 2001 to 2012 with respect to myocardial infarction, atrial fibrillation, ischaemic stroke, cardiovascular disease death and total death. The Proc Traj statistical procedure was used to identify resting heart rate trajectories. Results Five common long-term resting heart rate trajectories were identified: low, moderate, decreasing, increasing and elevated. In men, an elevated resting heart rate trajectory was independently associated with an increased risk of myocardial infarction when low resting heart rate trajectory was used as a reference (hazard ratio 1.83, 95% confidence interval 1.11-3.02). Risk of total death in men was lowest in the low resting heart rate trajectory group and highest in the increasing and elevated resting heart rate trajectory groups. In women, the association between resting heart rate trajectories and myocardial infarction was similar to that in men, but it was not significant. Conclusions Among the five long-term resting heart rate trajectories we identified, increasing and elevated trajectories were associated with an increased risk of myocardial infarction and total death in men. Our results suggest that changes in long-term individual resting heart rate in the general population may provide additional prognostic information.