Association between body mass index and the risk of bleeding in elderly patients with non-valvular atrial fibrillation taking dabigatran:a cohort study

Background Uncertainty remains regarding the association between body mass index(BMI)and the risk of bleeding in patients with non-valvular atrial fibrillation(NVAF).We aimed to investigate the association between BMI and the risk of bleeding in elderly NVAF patients taking dabigatran.Methods A total of 509 elderly NVAF patients,who were being treated at twelve centers in China from February 2015 to December 2017 and taking dabigatran,were analyzed.The exposure and outcome variables were BMI at baseline and bleeding events within the subsequent six months,respectively.Cox proportional hazards regression analysis was used to evaluate the association between BMI and the risk of bleeding.Moreover,the Cox proportional hazards regression with cubic spline functions and smooth curve fitting was conducted.Results During the six-month follow-up,50 participants experienced bleeding.Every 1 kg/m^2 increase in BMI was associated with a 12%increased risk of bleeding(P=0.021).Compared to those with BMI values in Tertile 1(<22.5 kg/m^2),the adjusted hazard ratio(HR)of bleeding for participants in Tertile 2(22.5–25.3 kg/m^2)and Tertile 3(>25.3 kg/m^2)were 2.71(95%CI:1.02–7.17)and 3.5(95%CI:1.21–8.70),respectively.The Ptrend-value was significant in all models.The adjusted smooth curve showed a linear association between BMI and bleeding.None of the stratified variables showed significant effect modification on the association between BMI and bleeding(Pinteraction>0.05).Conclusions BMI was significantly and positively associated with the risk of bleeding in elderly NVAF patients treated with dabigatran.

Individual and joint effects of borderline ankle-brachial index and high plasma total homocysteine on all-cause death in hypertensive adults

BACKGROUND The cardiovascular hazards of total homocysteine(tHcy)are long known.In addition,despite the acknow-ledgment on the importance of low ankle-brachial index(ABI)(<0.9),borderline ABI(0.91-0.99)was once commonly overlooked.This study aims to explore the independent and joint effect of tHcy level and borderline ABI on all-cause death in hypertensive population.METHODS This study included 10,538 participants from China H-type Hypertension Registry Study.ABI was described into two groups:normal ABI(1.00-1.40)and borderline ABI.tHcy level was also divided into two groups:<15.02 and≥15.02μmo/L.Four groups were analyzed,using COX proportional hazard regression model,separately and pairwise to observe the independ-ent and joint effect on all-cause death.RESULTS A total of 126(1.2%)deaths were observed in the 1.7 years follow-up time.Borderline ABI has a higher predicted risk of death than normal ABI(HR=1.87,95%CI:1.17-3.00)after adjusting for potential covariates.Compare with tHcy level<15.02μmo/L(low tHcy),those with tHcy≥15.02μmo/L(high tHcy)had higher risk to event outcome(HR=1.99,95%CI:1.30-3.05).According to the cumulative hazard curve,group with borderline ABI and high tHcy level has significantly higher altitude and larger increasing rate over follow-up period compare to other groups.Among those with borderline ABI,participants with high tHcy had higher death risk than those with low tHcy,nevertheless,no significant different between borderline and normal ABI among those with low tHcy levels.CONCLUSIONS Borderline ABI and tHcy level both have independent predictive value on all-cause death.The combined group of borderline ABI and high tHcy has highest risk factor of outcomes,which suggested the mutual additive value of border-line ABI and tHcy.More attention should be given to the importance of borderline ABI in hypertensive population,especially with elevated tHcy level.

Peripheral leukocyte count and risk of bleeding in patients with non-valvular atrial fibrillation taking dabigatran: a real-world study

Background: The association between peripheral leukocyte count and bleeding events in nonvalvular atrial fibrillation (NVAF) patients treated with dabigatran remains unclear. This study aimed to explore the association between leukocyte count and bleeding events after excluding other confounders in NVAF patients taking dabigatran. Methods: A total of 851 NVAF patients treated with dabigatran (110 mg bid) were recruited from 12 centers in China from February 2015 to December 2017. Follow-up was completed by May 2018. The exposure and outcome variables were leukocyte count measured at baseline and the number of bleeding events within the subsequent 6 months. Multivariate Cox proportional hazards models were constructed to analyze independent associations, and a Cox proportional hazards regression with cubic spline functions and smooth curve fitting (penalized spline method) was used to address nonlinearity between leukocyte count and bleeding. The inflection point was calculated using a recursive algorithm, and then a two-piecewise Cox proportional hazards model for both sides of the inflection point was constructed. Results: During 6-month follow-up, 87 participants occurred bleeding events. For every 1×10^9/L increase in leukocyte count, the risk of bleeding increased by 11%(hazard ratio [HR]: 1.11, 95% confidence interval [CI]: 0.99–1.25). The smooth curve showed nonlinear relationship between leukocyte count and bleeding events. The inflection point of the leukocyte count was 6.75×10^9/L. For leukocyte counts < 6.75×10^9/L, the HR (95% CI) was 0.88 (0.69–1.13), and for leukocyte counts ≥ 6.75×10^9/L, the HR (95% CI) was 1.28 (1.09–1.51). Conclusion: This study found a J-shaped association between baseline leukocyte count and risk of bleeding in NVAF patients treated with dabigatran.

Independent and joint association of physical activity and sedentary behavior on all-cause mortality

Backgrounds:Physical activity(PA)and sedentary behavior(SB)have been associated with mortality,while the joint association with mortality is rarely reported among Chinese population.We aimed to examine the independent and joint association of PA and SB with all-cause mortality in southern China.Methods:A cohort of 12,608 China Hypertension Survey participants aged≥35 years were enrolled in 2013 to 2014,with a follow-up period of 5.4 years.Baseline self-reported PA and SB were collected via the questionnaire.Kaplan–Meier curves(log-rank test)and Cox proportional hazards regression were performed to evaluate the associations of PA and SB on all-cause mortality.Results:A total of 11,744 eligible participants were included in the analysis.Over an average of 5.4 years of follow-up,796 deaths occurred.The risk of all-cause mortality was lower among participants with high PA than those with low to moderate level(5.2%vs.8.9%;hazards ratio[HR]:0.75,95%confidence interval[CI]:0.61–0.87).Participants with SB≥6 h had a higher risk of all-cause mortality than those with SB<6 h(7.8%vs.6.0%;HR:1.37,95%CI:1.17–1.61).Participants with prolonged SB(≥6 h)and inadequate PA(low to moderate)had a higher risk of all-cause mortality compared to those with SB<6 h and high PA(11.2%vs.4.9%;HR:1.67,95%CI:1.35–2.06).Even in the participants with high PA,prolonged SB(≥6 h)was still associated with the higher risk of all-cause mortality compared with SB<6 h(7.0%vs.4.9%;HR:1.33,95%CI:1.12–1.56).Conclusions:Among Chinese population,PA and SB have a joint association with the risk of all-cause mortality.Participants with inadequate PA and prolonged SB had the highest risk of all-cause mortality compared with others.