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Purpose
Although obesity has been associated with imbalances in cardiac autonomic nervous system, it is unclear whether there are differential relationships between adiposity measures and heart rate variability (HRV) measures. We aimed to examine differences in the relationship between adiposity measures and HRV indices in a healthy Korean population.Materials and Methods
In all, 1409 non-smokers (811 males, 598 females) without known histories of cardiovascular (CV), endocrine, or neurological diseases underwent adiposity measurements [(body mass index (BMI), percentage of body fat mass (PBF), and waist-to-hip ratio (WHR)], the HRV assessment (SDNN, RMSSD, LF, HF, LF/HF, and pNN50), and examination for CV risk factors (fasting glucose, LDL-cholesterol, HDL-cholesterol, triglycerides, hs-CRP, and blood pressure).Results
Compared with BMI and PBF, WHR was more strongly correlated with each HRV index and more likely to predict decreased HRV (<15 percentile vs. ≥15 percentile of each HRV index) in ROC curves analysis. In linear regression analysis, all adiposity measures were inversely associated with each HRV measure before adjusting for age, gender, and CV risk factors (p<0.05). After adjusting for the covariates, WHR was inversely related to RMSSD, LF, and pNN50; PBF with RMSSD, HF, and pNN50; BMI with RMSSD (p<0.05). The inversed association between HRV indices and the gender-specific WHR tertile was significant for subjects with BMI ≥25 kg/m2, but not for those with BMI <25 kg/m2.Conclusion
WHR and PBF appear to be better indicators for low HRV than BMI, and the association between abdominal adiposity and HRV may be stronger in overweight subjects. 相似文献Suicide is a leading cause of death in patients with schizophrenia. This nationwide cohort study investigated the incidence of each suicide method in patients with schizophrenia compared with the general population.
MethodsIn total, records of 174,039 patients with schizophrenia were obtained from the National Health Insurance Research Database in Taiwan from 2001 to 2016. This schizophrenia cohort was linked with the national mortality database, and 26,926 patients died during this follow-up period. Of the deceased, 3033 had died by suicide. Univariate Cox regression was used to estimate the demographic variables associated with suicide. We estimated the difference in the proportion of each suicide method used in patients with schizophrenia compared with the general population. The incidence and standardized mortality ratio (SMR) of each suicide method were calculated and stratified based on sex.
ResultsPatients aged 25–34 years exhibited the highest suicide risk. Compared with the general population, patients with schizophrenia were more likely to commit suicide by jumping and drowning and less likely to use charcoal-burning and hanging. Women showed a higher incidence of suicide by drowning and jumping than did men. Comorbidity with substance use disorders (SUDs) was associated with a high suicide SMR (26.9, 95% confidence interval [CI] = 23.4–28.9), particularly for suicide by jumping (61.2, 95% CI = 48.3–76.3).
ConclusionsPatients with schizophrenia had higher suicide rates for all methods than did the general population. Suicide method differed based on sex. Patients with SUDs exhibit a high SMR for each suicide method and warrant intensive clinical attention.
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