Jianghua Zhou

Insomnia with Physiological Hyperarousal is Associated with Hypertension.Hypertension.

Previous studies have suggested that insomnia with objective short sleep duration is associated with a higher risk of hypertension, and it has been speculated that the underlying mechanism is physiological hyperarousal. In this study, we tested whether insomnia with physiological hyperarousal measured by Multiple Sleep Latency Test (MSLT), a standard test of sleepiness/alertness, is associated with increased risk of hypertension. Two hundred nineteen chronic insomniacs and 96 normal sleepers were included in this study. Chronic insomnia was defined based on standard diagnostic criteria with symptoms lasting ≥6 months. All subjects underwent 1 night in laboratory polysomnography followed by a standard MSLT. We used the median mean MSLT value (ie, >14 minutes) and the 75th percentile of mean MSLT value (ie, >17 minutes) to define hyperarousal. Hypertension was defined based either on blood pressure measures or on diagnosis treatment by a physician. After controlling for age, sex, body mass index, apnea–hypopnea index, diabetes mellitus, smoking, alcohol, and caffeine use, insomnia combined with MSLT >14 minutes increased the odds of hypertension by 300% (odds ratio=3.27; 95% confidence interval=1.20–8.96), whereas insomnia combined with MSLT >17 minutes increased even further the odds of hypertension by 400% (odds ratio=4.33; 95% confidence interval=1.48–12.68) compared with normal sleepers with MSLT ⩽14 minutes. Insomnia associated with physiological hyperarousal is associated with a significant risk of hypertension. Long MSLT values may be a reliable index of the physiological hyperarousal and biological severity of chronic insomnia.

Association of vitamin D deficiency and frailty: A systematic review and meta-analysis

There is a biologically plausible association between low vitamin D, specifically serum 25-hydroxyvitamin D [25(OH)D] level, and frailty. We conducted a systematic review and meta-analysis to describe the association between low 25(OH)D level and frailty. We searched literature in OVID (Medline), EMBASE, Web of Knowledge and Cochrane CENTRAL Library Issue in May 2016, for cohort studies evaluating association of low 25(OH)D level with the risk of frailty. Studies were reviewed in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses(PRISMA) guidelines. A total of seven studies(17,815 participants)were eligible in our study. The prevalence of frailty ranged from 3.9% to 31.9%. The pooled OR of frailty for the lowest versus the highest level of vitamin D was 1.27 (95% CI=1.17-1.38, I2=59%), suggesting that low level of vitamin D was significantly associated with the risk of frailty. In addition, results of subgroups analysis indicated that low level of vitamin D was significantly associated with the risk of frailty in female (pooled OR=1.27, 95% CI=1.15-1.40). Similar result was also found when frailty was defined by the Fried criteria or the modified Fried criteria (pooled OR=1.25, 95% CI=1.14-1.37), and FRAIL scale (pooled OR=1.55, 95% CI=1.07-2.25). Compared to the highest level of 25(OH)D, the association between frailty and the lowest level of 25(OH)D was significant in our study.

The association between post-traumatic stress disorder and shorter telomere length: A systematic review and meta-analysis

OBJECTIVE Post-traumatic stress disorder (PTSD) is a common psychiatric disorder, which may accelerate aging. Many study have investigated the association between telomeres length and PTSD, but results from published studies are contradictory. Therefore, Meta-analysis approaches were conducted to give more precise estimate of relationship between telomere length and PTSD. METHOD We systematically reviewed the databases of PUBMED, PsycINFO, Medline(Ovid SP) and EMBASE for all articles on the association between telomere length and PTSD. Data were summarized by using random-effects in the meta-analysis. The heterogeneity among studies were examined by using Cochranes Q statistic and I-squared. RESULTS Five eligible studies containing 3851 participants were included in our meta-analysis. Shorten telomere length was significantly associated with PTSD with mean difference of -0.19( 95% CI: -0.27, -0.01; P<0.001) with I-square of 96%. The results from subgroup analysis demonstrated that shorter telomere length was significantly associated with PTSD across all gender groups, with mean difference of -0.15( 95% CI: -0.29, -0.01; P=0.04) for female, mean difference of -0.17( 95% CI: -0.19, -0.15; P<0.001) for male. Meanwhile, shorten telomere length was significantly associated with sexual assault(mean difference =-0.15, 95% CI: -0.29, -0.01), childhood trauma (mean difference =-0.08, 95% CI: -0.19, -0.07), but not combat (mean difference =-0.39, 95% CI: -0.83, 0.05). CONCLUSION Compared to the individuals without PTSD, individuals with PTSD have shorter telomere length, which has implications for early intervention and timely treatment to prevent future adverse health outcomes.

Effects of breast-feeding compared with formula-feeding on preterm infant body composition: a systematic review and meta-analysis

We conducted a systematic review and meta-analysis to compare the effect of breast-feeding and formula-feeding on body composition of preterm infants. We searched the literature using PubMed, Cochrane Central Library Issue, Ovid (Medline), Embase and other resources such as Google Scholar, electronic databases and bibliographies of relevant articles; two reviewers collected and extracted data independently. All the authors assessed risk of bias independently using the Newcastle-Ottawa Scale (NOS). A fixed-effects meta-analysis was undertaken with RevMan 5 software (The Cochrane Collaboration) using the inverse variance method (P≥0·05; χ 2 test). In contrast, a random-effects meta-analysis was carried out. Altogether, 630 articles were identified using search strategy, and the references within retrieved articles were also assessed. A total of six studies were included in this systematic review. In formula-fed infants, fat mass was higher at term (mean difference 0·24 (95 % CI 0·17, 0·31) kg), fat-free mass was higher at 36 weeks of gestational (mean difference 0·12 (95 % CI 0·04, 0·21) kg) and the percentage of fat mass was higher at 36 weeks of gestation (mean difference 3·70 (95 % CI 1·81, 5·59) kg) compared with breast-fed infants. Compared with breast-feeding, formula-feeding is associated with altered body composition from birth to term in preterm infants. The effects of formula-feeding on preterm infant body composition from term to 12-month corrected age are inconclusive in our study. Well-designed studies are required in the future to explore the effects of formula-feeding compared with breast-feeding.

Association between sarcopenia and nutritional status and physical activity among community-dwelling Chinese adults aged 60 years and older

The aim of the present study was to examine the association between sarcopenia and nutritional status and physical activity among community‐dwelling Chinese people aged 60 years and older.

The association between telomere length and frailty: A systematic review and meta-analysis

Background: Several studies have examined the association between telomere length and frailty, but results from these studies are contradictory. Therefore, we conducted a systematic review and meta‐analysis to examine the association between telomere length and frailty. Methods: We searched the literature in Ovid (MEDLINE), Embase, PubMed, Web of Knowledge and Cochrane databases in July 2017 for studies evaluating the association of telomere length and the risk of frailty. Results: A total of 5 studies (3268 participants) were eligible in our study. The prevalence of frailty ranged from 5.4% to 51.1%. The pooled mean difference of telomere length for the non‐frail versus frail was 0.06 (95% CI: −0.01, 0.13), suggesting that no significant association was found between telomere length and frailty. In addition, the subgroup analysis indicated that telomere length was not significantly associated with the risk of frailty in all gender groups. Similar results were also found when frailty was defined by the Fried criteria (mean difference = 0.07, 95% CI: −0.03, 0.16) and frailty index (mean difference = −0.02, 95% CI: −0.05, 0.01), but not by the frailty scale (mean difference = 0.18, 95% CI: 0.04, 0.32). Conclusion: Telomere length is not associated with the risk of frailty. Well‐designed prospective studies are needed to evaluate further whether telomere length is a meaningful biological marker for frailty.