Temporal Relationship Between Childhood Body Mass Index and Insulin and Its Impact on Adult Hypertension: The Bogalusa Heart Study

Bidirectional Association between Sarcopenia and Depressive Symptoms among Chinese Middle- and Older-Aged Adults: Longitudinal Observational Study

BACKGROUND

The study aimed to examine the bidirectional relationship between sarcopenia and depressive symptoms in a national, community-based cohort study, despite the unclear temporal sequence demonstrated previously.

METHODS

Data were derived from four waves (2011 baseline and 2013, 2015, and 2018 follow-ups) of the China Health and Retirement Longitudinal Study (CHARLS). A total of 17,708 participants aged 45 years or older who had baseline data on both sarcopenia status and depressive symptoms in 2011 were included in the study. For the two cohort analyses, a total of 8092 adults without depressive symptoms and 11,292 participants without sarcopenia in 2011 were included. Sarcopenia status was defined according to the Asian Working Group for Sarcopenia 2019 (AWGS 2019) criteria. Depressive symptoms were defined as a score of 20 or higher on the 10-item Center for Epidemiologic Studies Depressive Scale (CES-D-10). Cox proportional hazard regression models were conducted to examine the risk of depressive symptoms and sarcopenia risk, while cross-lagged panel models were used to examine the temporal sequence between depressive symptoms and sarcopenia over time.

RESULTS

During a total of 48,305.1 person-years follow-up, 1262 cases of incident depressive symptoms were identified. Sarcopenia exhibited a dose-response relationship with a higher risk of depressive symptoms (HR = 1.7, 95%CI: 1.2-2.3 for sarcopenia, and HR = 1.5, 95%CI: 1.2-1.8 for possible sarcopenia, p trend < 0.001). In the second cohort analysis, 240 incident sarcopenia cases were identified over 39,621.1 person-years. Depressive symptoms (HR = 1.5, 95%CI: 1.2-2.0) are significantly associated with a higher risk of developing sarcopenia after multivariable adjustment (p < 0.001, Cross-lagged panel analyses demonstrated that depressive symptoms were associated with subsequent sarcopenia (β = 0.003, p < 0.001). Simultaneously, baseline sarcopenia was also associated with subsequent depressive symptoms (β = 0.428, p < 0.001).

CONCLUSION

This study identified a bidirectional relationship between depressive symptoms and sarcopenia. It seems more probable that baseline sarcopenia is associated with subsequent depressive symptoms in a stronger pattern than the reverse pathway. The interlinkage indicated that maintaining normal muscle mass and strength may serve as a crucial intervention strategy for alleviating mood disorders.

Temporal relationships between blood glucose, lipids and BMI, and their impacts on atherosclerosis: a prospective cohort study

OBJECTIVES

This study aimed to explore the temporal relationship between blood glucose, lipids and body mass index (BMI), and their impacts on atherosclerosis (AS).

DESIGN

A prospective cohort study was designed.

SETTING AND PARTICIPANTS

A total of 2659 subjects from Harbin Cohort Study on Diet, Nutrition and Chronic Non-communicable Diseases, and aged from 20 to 74 years were included.

PRIMARY AND SECONDARY OUTCOME MEASURES

Body weight, height, fasting blood glucose (FBG) and 2-hour postprandial glucose (2-h PG), blood lipids including total cholesterol (TC), triglyceride (TG), low-density lipoprotein cholesterol (LDL-c) and high-density lipoprotein cholesterol (HDL-c) were measured at baseline and follow-up. Brachial ankle pulse wave velocity (baPWV) was examined at follow-up as a marker of AS risk. Logistic regression analysis, cross-lagged path analysis and mediation analysis were performed to explore the temporal relationships between blood glucose, lipids and BMI, and their impacts on AS risk.

RESULTS

Logistic regression analysis indicated that increased FBG, 2-h PG, TC, TG, LDL-c and BMI were positively associated with AS risk, while increased HDL-c was negatively associated with AS risk. The path coefficients from baseline blood parameters to the follow-up BMI were significantly greater than those from baseline BMI to the follow-up blood parameters. Mediation analysis suggested that increased FBG, 2-h PG, TC, TG and LDL-c could increase AS risk via increasing BMI, the effect intensity from strong to weak was LDL-c>TC>TG>FBG>2 h PG, while increased HDL-c could decrease AS risk via decreasing BMI.

CONCLUSIONS

Changes in blood glucose and lipids could cause change in BMI, which mediated the impacts of blood glucose and lipids on AS risk. These results highlight the importance and provide support for the early and comprehensive strategies of AS prevention and control.

Light pollution during pregnancy influences the growth of offspring in rats

OBJECTIVE

To investigate the effects of excessive light exposure during gestation on intrauterine development and early growth of neonates in rats.

METHODS

Pregnant rats were randomly allocated to three groups: the constant light exposure group, non-light exposure group and control group. Blood samples were collected from the tail vein to analyze melatonin and cortisol levels. Weight, daily food and water consumption were recorded. Uterine weight, placental weight and placental diameter were measured on gestational day 19. Natural birth and neonate growth were also monitored. The expression of NR1D1(nuclear receptor subfamily 1 group D member 1) in offspring's SCN (suprachiasmatic nuclei), liver and adipose tissue was measured. Expression of NR1D1, MT1(melatonin 1 A receptor) and 11β-HSD2 (placental 11β-hydroxysteroid dehydrogenase type 2) in placenta was also measured. Finally, the expression of MT1 and 11β-HSD2 in NR1D1 siRNA transfected JEG-3 cells was evaluated.

RESULTS

There were no significant differences in maternal weight gain, pregnancy duration, uterine weight, placental body weight, placental diameter, fetal number among three groups. There were no significant differences in weights or lengths of offspring at birth. Compared to other two groups, constant light exposure group showed significantly more rapid growth of offspring in 21st day post-birth. The expression of NR1D1 in SCN, liver and adipose tissues of offspring was not significantly different among three groups. The maternal serum melatonin and cortisol levels of the constant light exposure group were lower and higher than other two groups, respectively. The expressions of NR1D1, MT1 and 11β-HSD2 were all decreased in placenta of the constant light exposure group. The expression of MT1 and 11β-HSD2 in JEG-3 cells were decreased after NR1D1 siRNA transfection.

CONCLUSION

Excessive light exposure during pregnancy results in elevated cortisol and reduced melatonin exposure to fetuses in uterus, potentially contributing to an accelerated early growth of offspring in rats.

Temporal relationship between arterial stiffness and blood pressure variability and joint effect on cardiovascular disease

Although arterial stiffness measured by brachial-ankle pulse wave velocity (baPWV) and blood pressure (BP) significantly correlated, the relationship between baPWV and BP variation (BPV) was unclear. This study aimed to examine the temporal relationship between brachial-ankle pulse wave velocity (baPWV) and systolic blood pressure variation (SBPV) and their joint effect on the development of cardiovascular disease (CVD). This study included 6632 participants with repeated assessments of baPWV and BP during 2006 to 2018. The baseline and follow-up SBPV was calculated as absolute SBP difference divided by mean SBP over sequential visits, using data between 2006-2010 and 2014-2018, respectively. Cross-lagged analysis was used to assess the temporal relation between baPWV and SBPV, and logistic analysis was used to assess the joint effect of baPWV and SBPV on CVD. After adjustment for confounder, the path coefficient from baseline baPWV to follow-up SBPV (β1 = 0.040; P = 0.0012) was significantly had greater than the path from baseline SBPV to follow-up baPWV (β2 = 0.009; P = 0.3830), with P = 0.0232 for the difference between β1 and β2. This unidirectional relationship from baseline baPWV to follow-up SBPV was consistent in patients without hypertension, with isolated systolic, high systolic and diastolic, uncontrolled and controlled hypertension. In addition, participants with high levels of baseline baPWV and follow-up SBPV had greater risk of CVD (odds ratio, 5.82; 95% confidence interval, 2.50-12.60) than those with low-low levels. The findings suggested that arterial stiffness appeared to precede the increase in SBPV and their joint effect is predictive of the development of CVD.

Temporary relationship between sleep duration and depression and its impact on future risk of cardiovascular disease

BACKGROUND

Although sleep duration and depression were correlated, their temporal sequence and how the sequence influence on future risk of cardiovascular disease (CVD) remained undetermined. This study aimed to explore the temporal relationship between sleep duration and depression, and its association with future CVD risk.

METHODS

We included 10,629 middle-aged and elderly participants with repeated measurements of sleep duration and depressive symptoms (measured by Center for Epidemiological Studies-Depression scale [CESD]) at the first two visits from the China Health and Retirement Longitudinal Study. Cross-lagged analysis and mediation analysis were used to examine the temporal relationship between sleep duration and depression and its impact on future risk of CVD.

RESULTS

The adjusted cross-lagged path coefficient from baseline sleep duration to follow-up CES-D (β1 = -0.191; 95 % confidence interval [CI], -0.239 to -0.142) was significantly greatly than that from baseline CES-D to follow-up sleep duration (β2 = -0.031; 95 % CI, -0.031 to -0.024) (Pdifference < 0.0001). Similarly, the path coefficient from baseline sleep duration to annual changes in CES-D was significantly greater than that from baseline CES-D to annual changes in sleep duration (β1 = -0.093 versus β2 = -0.015, Pdifference < 0.0001). The path coefficient from baseline sleep duration to follow-up CES-D in CVD group was significantly greater than that in those without CVD (Pdifference of β1 = 0.0378). Furthermore, 27.93 % of the total association of sleep duration with CVD was mediated by depression symptoms.

CONCLUSIONS

The findings provide evidence that decrease in sleep duration probably precedes the increased in depressive symptoms, and depression partially mediated the pathway from sleep duration to incident CVD.

Dynamics, association, and temporal sequence of cognitive function and frailty: a longitudinal study among Chinese community-dwelling older adults

BACKGROUND

Little is known about the association of longitudinal dynamics between cognitive function and frailty in Chinese older adults. The temporal sequences between cognitive function and frailty remains unclear. Our study investigates this directionality association using longitudinal data.

METHODS

Latent growth and multivariate latent growth models were employed to examine dynamics of cognition and frailty and their association among 2824 older adults in China. Cross-lagged panel analyses were used to assess the temporal sequences between frailty and cognition. The relation between cognitive domains and frailty was also examined using aforementioned methods.

RESULTS

Cognitive function was negatively associated with frailty status. Higher initial level of cognition indicated lower baseline level (β=-0.175, P < 0.001) and change rate (β=-0.041, P = 0.002) of frailty. We observed a reciprocal association between frailty and cognitive function rather than a unidirectional causal relationship. The initial cognitive performance for all components were negatively associated with baseline (β ranged between - 0.098 to -0.023) and change rate (β ranged between - 0.007 to -0.024) of frail status. No consistent associations between change rate of cognitive components and either initial level or change rate of frailty were detected.

CONCLUSIONS

Our study detected a reciprocal association between cognition and frailty rather than a unidirectional causal relationship. Our results also revealed different connections between cognitive performance and frailty across diverse cognitive domains.

Metformin reduces insulin resistance and attenuates progressive renal injury in prepubertal obese Dahl salt-sensitive rats

Prepubertal obesity is currently an epidemic and is considered as a major risk factor for renal injury. Previous studies have demonstrated that insulin resistance contributes to renal injury in obesity, independent of diabetes. However, studies examining the relationship between insulin resistance and renal injury in obese children are lacking. Recently, we reported that progressive renal injury in Dahl salt-sensitive (SS) leptin receptor mutant (SSLepRmutant) rats was associated with insulin resistance before puberty. Therefore, the aim of the present study was to examine whether decreasing insulin resistance with metformin will reduce renal injury in SSLepRmutant rats. Four-wk-old SS and SSLepRmutant rats were separated into the following two groups: 1) vehicle and 2) metformin (300 mg/kg/day) via chow diet for 4 wk. Chronic administration of metformin markedly reduced insulin resistance and dyslipidemia in SSLepRmutant rats. We did not detect any differences in mean arterial pressure between vehicle and metformin-treated SS and SSLepRmutant rats. Proteinuria was significantly greater in SSLepRmutant rats versus SS rats throughout the study, and metformin administration significantly reduced proteinuria in SSLepRmutant rats. At the end of the protocol, metformin prevented the renal hyperfiltration observed in SSLepRmutant rats versus SS rats. Glomerular and tubular injury and renal inflammation and fibrosis were significantly higher in vehicle-treated SSLepRmutant rats versus SS rats, and metformin reduced these parameters in SSLepRmutant rats. These data suggest that reducing insulin resistance with metformin prevents renal hyperfiltration and progressive renal injury in SSLepRmutant rats before puberty and may be therapeutically useful in managing renal injury during prepubertal obesity.NEW & NOTEWORTHY Childhood/prepubertal obesity is a public health concern that is associated with early signs of proteinuria. Insulin resistance has been described in obese children. However, studies investigating the role of insulin resistance during childhood obesity-associated renal injury are limited. This study provides evidence of an early relationship between insulin resistance and renal injury in a rat model of prepubertal obesity. These data also suggest that reducing insulin resistance with metformin may be renoprotective in obese children.

Association of dietary fibre intake with subsequent fasting glucose levels and indicators of adiposity in school-age Japanese children

OBJECTIVE

To evaluate the relationships of fibre intake with subsequent BMI sd-score, waist-to-height ratio and serum fasting glucose levels among school-age Japanese children.

DESIGN

This is a prospective study of school-age Japanese children. Participants were followed from 6-7 to 9-10 years of age (follow-up rate: 92·0 %). Fibre intake was assessed using a validated FFQ. Serum fasting glucose was measured by a hexokinase enzymatic method. Using a general linear model, the associations between dietary fibre intake at baseline and BMI sd-score, waist-to-height ratio, and serum levels of fasting glucose at follow-up were evaluated after considering potential confounding factors.

SETTING

Public elementary schools in a city in Japan.

PARTICIPANTS

A total of 2784 students.

RESULTS

The estimated means for fasting glucose at 9-10 years of age were 86·45, 85·68, 85·88 and 85·58 mg/dl in the lowest, second, third and highest quartile of fibre intake at 6-7 years of age, respectively (P = 0·033, trend P = 0·018). Higher fibre intake at 6-7 years of age was associated with lower waist-to-height ratio at 9-10 years of age (trend P = 0·023). The change in fibre intake was inversely associated with concurrent change of BMI sd-score (trend P = 0·044).

CONCLUSION

These results suggest that dietary fibre intake may be potentially effective to limit excess weight gain and lower glucose levels during childhood.

Temporal relationship between hyperuricemia and hypertension and its impact on future risk of cardiovascular disease

BACKGROUND

Although hyperuricemia and hypertension are significantly correlated, their temporal relationship and whether this relationship is associated with risk of cardiovascular disease (CVD) are largely unknown. This study aimed to examine temporal relationship between hyperuricemia and hypertension, and its association with future risk of CVD.

METHODS

This study included 60,285 participants from the Kailuan study. Measurement of serum uric acid (SUA), systolic and diastolic blood pressure (SBP and DBP) were obtained twice at 2006 (baseline) and 2010. Cross-lagged and mediation analysis were used to examine the temporal relationship between hyperuricemia and hypertension, and the association of this temporal relationship with CVD events risk after 2010.

RESULTS

After adjusting for covariates, the cross-lagged path coefficients (β1) from baseline SUA to follow-up SBP and DBP were significantly greatly than path coefficients (β2) from baseline SBP and DBP to follow-up SUA (β1=0.041 versus β2=0.003; Pdifference<0.0001 for SBP; β1=0.040 versus β2=0.000; Pdifference<0.0001 for DBP). The path coefficients from baseline SUA to follow-up SBP and DBP in group with incident CVD were significantly greatly than that in group without incident CVD (Pdifference of β1 in the two groups was 0.0018 for SBP and 0.0340 for DBP). Furthermore, SBP and DBP partially mediated the effect of SUA on incident CVD, the mediation effect was 57.64% for SBP and 46.27% for DBP. Similar mediated results were observed for stroke and myocardial infarction.

CONCLUSION

Increased SUA levels probably precede elevated BP, and BP partially mediates the pathway from SUA to incident CVD.

Arterial stiffness and blood pressure in treated hypertension: a longitudinal study

OBJECTIVES

It has been reported that an increase in arterial stiffness precedes an increase in blood pressure (BP) in the general population. Whether BP lowering results from of reducing arterial wall or vice versa in antihypertensive treatment is unclear. This study aimed to investigate the association between arterial stiffness and BP in patients with treated hypertension.

METHODS

This study included 3277 participants who were treated with antihypertensive agents and with repeated measurements of branchial-ankle pulse wave velocity (baPWV) and BP during 2010-2016 from the Kailuan study. Temporal relation between baPWV and BP was assessed by cross-lagged path analyses.

RESULTS

After adjustment for potential confounders, the standard regression coefficient from baseline baPWV to follow-up SBP was 0.14 [95% confidence interval (95% CI), 0.10-0.18], which was significantly greater than that from baseline SBP to follow-up baPWV (0.05; 95% CI, 0.02-0.08) ( P  < 0.0001 for difference). Similar results were observed for the cross-lagged analysis with changes of baPWV and mean arterial pressure. Further analysis showed that the yearly rate of change in SBP during the follow-up period significantly varied across increasing quartiles of baseline baPWV ( P  < 0.0001), whereas the yearly rate of change in baPWV showed a nonsignificantly varied trend across quartiles of baseline SBP ( P  = 0.2443).

CONCLUSION

These findings provided strong evidence that reduction in arterial stiffness through antihypertensive treatment could precede BP lowering.

Associations of selenium exposure with blood lipids: Exploring mediating DNA methylation sites in general Chinese urban non-smokers

Selenium (Se) is widely distributed in the total environment and people are commonly exposed to Se, while the potential effects and mechanisms of Se exposure on blood lipids have not been well established. This study aimed to assess the associations of urinary Se (SeU) with blood lipids and explore the potential mediating DNA methylation sites. We included 2844 non-smoke participants from the second follow-up (2017-2018) of the Wuhan-Zhuhai cohort (WHZH) in this study. SeU and blood lipids [i.e., total cholesterol (TC), triglycerides (TG), low-density lipoprotein cholesterol (LDL), and high-density lipoprotein cholesterol (HDL)] for all participants were determined. The associations of SeU with blood lipids were analyzed by generalized linear models. Then, we conducted the blood lipids related epigenome-wide association studies (EWAS) among 221 never smokers, and the mediation analysis was conducted to explore the potential mediating cytosine-phosphoguanine (CpG) sites in the above associations. In this study, the SeU concentration of the participants in this study was 1.40 (0.94, 2.08) μg/mmol Cr. The SeU was positively associated with TC and LDL, and not associated with TG and HDL. We found 131, 3, and 1 new CpG sites related to TC, HDL, and LDL, respectively. Mediation analyses found that the methylation of cg06964030 (within MIR1306) and cg15824094 (within PLCH2) significantly mediated the positive association between SeU and TC. In conclusion, high levels of Se exposure were associated with increased TC and LDL among non-smokers, and the methylation of MIR1306 and PLCH2 partly mediated Se-associated TC increase. These findings provide new insights into the effects and mechanisms of Se exposure on lipids metabolism and highlight the importance of controlling Se exposure and intake for preventing high blood lipids.

Temporal relationship between sleep duration and obesity among Chinese Han people and ethnic minorities

BACKGROUND

No studies have assessed the association between sleep duration and obesity in Chinese ethnic minorities. Whether the relationship between sleep duration and obesity is different between Chinese Han people and Chinese ethnic minorities remains unclear. The study aimed to explore the relationship between sleep duration and obesity among Chinese Han people and Chinese ethnic minorities.

METHODS

We applied data from the Guizhou Population Health Cohort Study (GPHCS), which 9,280 participants were recruited in the baseline survey from 2010 to 2012, and 8,163 completed the follow-up survey from 2016 to 2020. A total of 5,096 participants (3,188 Han Chinese and 1,908 ethnic minorities) were included in the ultimate analysis. Information on sleep duration (total 24-hour sleep time), body mass index (BMI), and waist circumference (WC) was collected at the baseline and follow-up survey, respectively. Cross-lagged panel analyses were conducted to explore the temporal relationship between sleep duration and obesity for Han people and ethnic minorities.

RESULTS

For Han people, the results from cross-lagged panel analyses indicated that baseline sleep duration was significantly associated with follow-up BMI (β_BMI = -0.041, 95% CI_BMI: -0.072 ~ -0.009) and follow-up WC (β_WC = -0.070, 95%CI_WC: -0.103 ~ -0.038), but baseline BMI (β_BMI = -0.016, 95% CI_BMI: -0.050 ~ 0.018) and baseline WC (β_WC = -0.019, 95% CI_WC: -0.053 ~ 0.016) were not associated with follow-up sleep duration. In addition, the relationship between baseline sleep duration and follow-up BMI was gender-specific and significant only in the Han people female (β_BMI = -0.047, 95% CI_BMI: -0.090 ~ -0.003) but not in the Han people male (β_BMI = -0.029, 95% CI_BMI: -0.075 ~ 0.016). For ethnic minorities, the results indicated that there was no relationship between sleep duration and obesity at all, either from sleep duration to obesity (β_BMI = 0.028, 95%CI_BMI: -0.012 ~ 0.068; β_WC = 0.020, 95%CI_WC: -0.022 ~ 0.062), or from obesity to sleep duration (β_BMI = -0.022, 95%CI_BMI: -0.067 ~ 0.022; β_WC = -0.042, 95%CI_WC: -0.087 ~ 0.003).

CONCLUSION

The relationship pattern between sleep duration and obesity across Han people and ethnic minorities is different. Future sleep-aimed overweight and obesity intervention should be conducted according to population characteristics.

The Bidirectional Association Between Cognitive Function and Gait Speed in Chinese Older Adults: Longitudinal Observational Study

BACKGROUND

Cognitive and gait speed decline are common conditions in older adults and are often associated with future adverse consequences. Although an association between cognitive function and gait speed has been demonstrated, its temporal sequence remains unclear, especially in older Chinese adults. Clarifying this could help identify interventions to improve public health in older adults.

OBJECTIVE

This study aims to examine the longitudinal reciprocal association between gait speed and cognitive function and the possible temporal sequence of changes in both factors in a national longitudinal cohort.

METHODS

Data were derived from 2 waves (2011 baseline and 2015 follow-up) of the China Health and Retirement Longitudinal Study (CHARLS). Participants 60 years or older, without dementia or Parkinson disease at baseline, and with completed data on gait speed and cognition at both baseline and follow-up were included. Usual gait speed was measured over two 2.5-m walks. Mental intactness and episodic memory were used to assess global cognitive function. Cross-lagged panel models and linear mixed-effects models were used to examine the association between cognition and gait speed over time. Standardized coefficients were reported.

RESULTS

A total of 3009 participants (mean age 66.4 years, SD 5.4 years; 1422/3009, 47.26%, female participants) were eligible for inclusion in our analyses. Cross-lagged panel analyses revealed that after accounting for baseline gait speed, cognition, and potential confounders, baseline global cognition (β=.117, 95% CI 0.082-0.152; P<.001), mental intactness (β=.082, 95% CI 0.047-0.118; P<.001), and episodic memory (β=.102, 95% CI 0.067-0.137; P<.001) were associated with subsequent gait speed. Simultaneously, baseline gait speed was also associated with subsequent global cognition (β=.056, 95% CI 0.024-0.087; P=.001), mental intactness (β=.039, 95% CI 0.008-0.069; P=.01), and episodic memory (β=.057, 95% CI 0.023-0.092; P=.001). The comparison of standardized cross-lagged coefficients suggested that the effect size of baseline global cognition on subsequent gait speed was significantly larger than the reverse effect (χ₁²=6.50, P for difference=.01). However, the effects of both mental intactness and episodic memory on subsequent gait speed were not significantly stronger than those of the reverse pathway (χ₁²=3.33, P for difference=.07 and χ₁²=3.21, P for difference=.07). Linear mixed-effects analyses further supported these bidirectional relationships, revealing that lower baseline cognitive scores predicted steeper declines in gait speed trajectory, and slower baseline gait speed predicted more declines in cognitive trajectory over time.

CONCLUSIONS

There is a longitudinal bidirectional association between usual gait speed and both global cognitive function and specific domains of mental intactness and episodic memory among Chinese older adults. Baseline global cognition is likely to have a stronger association with subsequent gait speed than the reverse pathway. This interlinkage is noteworthy and may have implications for public health. Maintaining normal cognitive function may be an important interventional strategy for mitigating age-related gait speed reduction.

Association of triglyceride-glucose index and its 6-year change with risk of hypertension: A prospective cohort study

BACKGROUND AND AIM

We aimed to investigate the association of triglyceride-glucose (TyG) index and its dynamic change with risk of hypertension in rural Chinese and, further, to explore whether the TyG index mediates the obesity-related hypertension.

METHODS AND RESULTS

A prospective cohort study, including 10,309 subjects without hypertension at baseline, was conducted in 2007-2008 and followed up in 2013-2014. TyG index was calculated as Ln[fasting triglycerides (mg/dL) × fasting glucose (mg/dL)/2]. Logistic regression model was used to estimate the odds ratios (ORs) and 95% confidence intervals (CIs). Mediation analysis was performed to examine the contribution of the TyG index to the association of obesity-hypertension incidence. During a median follow-up of 6 years, 2073 subjects developed hypertension. In multivariate logistic model adjusted for age, sex, alcohol drinking, smoking, physical activity and education, monthly income, family history of hypertension, TC, and HDL-C, the risk of hypertension was 1.14 (1.07-1.22) for per-SD increase in TyG. After additional controlling for obesity, this association was nonsignificant (1.06, 0.99-1.13) and (1.05, 0.99-1.13) for BMI and WC, respectively. Increasing trends were found for hypertension incidence as the TyG change increased, with or without adjustment for obesity (all P_trend < 0.05). With per-SD increment in TyG change, the risks of hypertension incidence were 1.14 (1.07-1.22) for absolute TyG change, and 1.15 (1.08-1.22) for relative TyG change in multivariate logistic model; the results were significant after further adjustment for BMI or WC, respectively. The TyG index partially mediated the obesity-incident hypertension association: 6.84% for BMI and 6.68% for WC, respectively.

CONCLUSIONS

Elevated TyG index and its dynamic change were positively associated with risk of incident hypertension in rural Chinese population, and the TyG index may play a partially mediating role in obesity-related incident hypertension.

Effect of Club cell secretory proteins on the association of tobacco smoke and PAH co-exposure with lung function decline: A longitudinal observation of Chinese coke oven workers

BACKGROUND

Exposure to polycyclic aromatic hydrocarbons (PAH) and tobacco smoke is associated with epithelial damage and reduced lung function. Club cell secretory protein (CC16) is a known biomarker for lung epithelial cells. However, the potential relationships between PAH and tobacco smoke exposure, CC16 levels, and reduced lung function remain unclear.

OBJECTIVES

This longitudinal study aimed to explore the potential role of CC16 in the association of tobacco smoke and PAH co-exposure with lung function.

METHODS

We enrolled 313 workers from a coking plant in China in 2014 and followed them up in 2019. The concentrations of PAH and nicotine metabolites in urine were determined using high-performance liquid chromatography (HPLC) with a fluorescence detector and HPLC-tandem mass spectrometry, respectively. The plasma CC16 concentration was determined using an enzyme-linked immunosorbent assay.

RESULTS

An analysis of the generalized estimating equation showed that each 1-unit increase in log-transformation of the last tertile of trans-3'-hydroxycotinine (3HC) was associated with a 3.30 ng/ml decrease in CC16. Restricted cubic spline analysis revealed a significant nonlinear dose-effect association between cotinine (COT) and CC16 (P_nonlinear = 0.018). In the low- CC16 subgroup, we found a significant association between total nicotine metabolites and forced vital capacity (FVC%) (β: 1.45, 95% CI: 2.87, -0.03), and the associations of nicotine (NIC), COT, and 3HC with FVC% were all of marginal significance. High levels of total hydroxyl polycyclic aromatic hydrocarbons (ΣOH-PAH) and NIC in the urine had an interactive effect on the decline of CC16 (P < 0.05). Cross-lagged panel analysis indicated that the decrease in CC16 preceded the decrease in FVC%. CC16 mediated the association between elevated nicotine metabolites and decreased FVC% in the low- CC16 subgroup.

CONCLUSIONS

CC16 plays an essential role in the association of PAH and tobacco smoke exposure with reduced lung function. Coke oven workers with low plasma CC16 levels are more likely to experience decreased lung function after tobacco smoke exposure.

BMI mediates the association of family medical history with self-reported hypertension and diabetes among older adults: Evidence from baseline wave of the longitudinal aging study in India

Background

This study explored the association between family history of hypertension and diabetes with their diagnosis among older Indian adults. The study further examined the role of body mass index (BMI) as a potential mediator in these associations.

Methods

Data from the Longitudinal Ageing Study in India (LASI, 2017-18), wave-1 were used. The sample for the study included 31,464 older adults aged 60 years and above. Descriptive statistics and bivariate analysis has been conducted to assess the prevalence of self-reported hypertension and diabetes. Further, multivariable logistic regression models were used to test the research hypotheses of this study. The Karlson-Holm-Breen (KHB) mediation analysis was conducted to recover the direct and indirect effects of BMI in the association of family medical history and diagnosis of hypertension and diabetes.

Results

A proportion of 32.70% of older adults were diagnosed with hypertension and 14.23% of older adults were diagnosed with diabetes. A proportion of 19.48% and 14.69% of older adults had a family history of hypertension and diabetes, respectively. Also, 16.57% and 5.53% of older adults were overweight and obese, respectively in the current study. Older adults who had family history of hypertension had higher odds of being diagnosed with hypertension [aOR: 2.23, CI: 2.07-2.39] than those who had no such family history. This association was mediated by BMI (percent mediated: 6.31%). Similarly, older adults who had family history of diabetes had higher odds of being diagnosed with diabetes [aOR: 2.63, CI: 2.41-2.88] than those who had no such family history. This association was mediated by BMI (percent effect mediated: 6.66%).

Conclusion

The study highlights the relevance of using family medical history data along with information on BMI as potential source for the control and management of hypertension and diabetes among older population.

Temporal sequence of blood lipids and insulin resistance in perimenopausal women: the study of women's health across the nation

INTRODUCTION

To explore the temporal relationship between blood lipids and insulin resistance in perimenopausal women.

RESEARCH DESIGN AND METHODS

The longitudinal cohort consisted of 1386 women (mean age 46.4 years at baseline) in the Study of Women's Health Across the Nation. Exploratory factor analysis was used to identify appropriate latent factors of lipids (total cholesterol (TC); triglyceride (TG); high-density lipoprotein cholesterol (HDL-C); low-density lipoprotein cholesterol (LDL-C); lipoprotein A-I (LpA-I); apolipoprotein A-I (ApoA-I); apolipoprotein B (ApoB)). Cross-lagged path analysis was used to explore the temporal sequence of blood lipids and homeostasis model assessment of insulin resistance (HOMA-IR).

RESULTS

Three latent lipid factors were defined as: the TG factor, the cholesterol transport factor (CT), including TC, LDL-C, and ApoB; the reverse cholesterol transport factor (RCT), including HDL-C, LpA-I, and ApoA-I. The cumulative variance contribution rate of the three factors was 86.3%. The synchronous correlations between baseline TG, RCT, CT, and baseline HOMA-IR were 0.284, -0.174, and 0.112 (p<0.05 for all). After adjusting for age, race, smoking, drinking, body mass index, and follow-up years, the path coefficients of TG→HOMA-IR (0.073, p=0.004), and HOMA-IR→TG (0.057, p=0.006) suggested a bidirectional relationship between TG and HOMA-IR. The path coefficients of RCT→HOMA-IR (-0.091, P < 0.001) and HOMA-IR→RCT (-0.058, p=0.002) were also significant, but the path coefficients of CT→HOMA-IR (0.031, p=0.206) and HOMA-IR→CT (-0.028, p=0.113) were not. The sensitivity analyses showed consistent results.

CONCLUSIONS

These findings provide evidence that TG and the reverse cholesterol transport-related lipids are related with insulin resistance bidirectionally, while there is no temporal relationship between the cholesterol transport factor and insulin resistance.

Interaction of polycyclic aromatic hydrocarbon exposure and high-fasting plasma glucose on lung function decline in coke oven workers: a cross-lagged panel analysis

Individuals with abnormal fasting plasma glucose (FPG) may be more susceptible to lung diseases associated with environmental pollutants. A cross-sectional survey of 629 workers in 2017 and a panel study of 304 workers from 2014 to 2019 were performed in China. The results showed that elevated total hydroxylated polycyclic aromatic hydrocarbon (ΣOH-PAH) concentration was associated with lower the percentage of predicted forced vital capacity (FVC%) among high-FPG workers (β for the cross-sectional analysis: -1.78%, 95%CI: -2.92%, -0.64%; β for the panel study: -1.10%, 95%CI: -2.19%, -0.02%). The absolute value of the cross-lagged path coefficient from FPG to FVC% (β₂ = -0.096) was significantly greater than that from FVC% to FPG (β₁ = 0.037). Our results suggest that FPG abnormalities may precede the lung function decline induced by PAH exposure and that high-FPG and high ΣOH-PAH levels have an interactive effect on lung function decline.

Association Between Body Weight and Telomere Length Is Predominantly Mediated Through C-Reactive Protein

CONTEXT

Both obesity and inflammation are related to accelerated aging. It is not yet known whether inflammation mediates the effects of obesity on aging.

OBJECTIVE

This work aims to dissect the direct effect of body mass index (BMI) and its indirect effect through C-reactive protein (CRP) on leukocyte telomere length (LTL) to determine the mediation effect of CRP on the BMI-LTL association.

METHODS

The study cohort included 5451 adults (1404 Mexican American, 3114 White, and 933 Black individuals; 53.5% male; mean age = 49.2 years) from the 1999 to 2002 National Health and Nutrition Examination Survey. General mediation models were used to examine the mediation effect of CRP on the BMI-LTL association.

RESULTS

After adjusting for age, race, sex, physical activity, alcohol use, and serum cotinine, the total effect of BMI on LTL was significant (standardized regression coefficient, β = -.054, P < .001) without CRP included in the model. With inclusion of CRP in the model, the indirect effect of BMI on LTL through CRP was estimated at β equal to -.023 (P < .001), and the direct effect of BMI on LTL in its absolute value decreased to β equal to -.031 (P = .025). The mediation effect of CRP was estimated at 42.6%. The mediation model parameters did not differ significantly between race and sex groups.

CONCLUSION

These results suggest that the inverse BMI-LTL association is partly mediated by obesity-induced inflammation. The significant direct effect of BMI on LTL with removal of the mediation effect through CRP indicates that obesity is associated with LTL attrition also through other noninflammatory mechanisms.

The mediation role of SOCS3 methylation in the effect of serum testosterone on type 2 diabetes

BACKGROUND

Previous studies reported that testosterone and DNA methylation of suppressor of cytokine signaling-3 (SOCS3) were associated with type 2 diabetes (T2D). Testosterone affects SOCS3 gene expression. Therefore, we aimed to investigate how the SOCS3 methylation mediates the relationship between testosterone and T2D among Chinese rural adults.

METHODS

A case-control study comprised 365 T2D patients and 651 controls was conducted. Liquid chromatography-tandem mass spectrometry and MethylTarget were used to determine the levels of serum testosterone and DNA methylation of SOCS3 gene, respectively. The odds ratio (OR) of testosterone or SOCS3 methylation for T2D was calculated using logistic regression models, and β value of testosterone for SOCS3 methylation was evaluated by linear regression models. Furthermore, through mediation analysis the mediating effect of SOCS3 methylation on the association of testosterone with T2D was estimated.

RESULTS

After adjusting for multiple variables, the protective effect of testosterone on T2D was found in men (OR = 0.61, 95% confidence interval [CI]: 0.47-0.80), and the methylation of Chr17:76356190 or Chr17:76356199 was negatively related to T2D in both men and women. Moreover, testosterone was positively associated with Chr17:76356190 methylation in men and Chr17:76356199 methylation in women (both P < .05). The mediation analysis showed that the Chr17:76356190 methylation partly mediated effect of testosterone on T2D in men was approximately 8.2%.

CONCLUSIONS

High levels of serum testosterone in men and Chr17:76356190 and Chr17:76356199 (SOCS3) methylation were related to a lower prevalent T2D. In addition, Chr17:76356190 methylation partially mediated the effect of testosterone on T2D in Chinese rural men.

Phenome-wide investigation of the causal associations between childhood BMI and adult trait outcomes: a two-sample Mendelian randomization study

Background

Childhood obesity is reported to be associated with the risk of many diseases in adulthood. However, observational studies cannot fully account for confounding factors. We aimed to systematically assess the causal associations between childhood body mass index (BMI) and various adult traits/diseases using two-sample Mendelian randomization (MR).

Methods

After data filtering, 263 adult traits genetically correlated with childhood BMI (P < 0.05) were subjected to MR analyses. Inverse-variance weighted, MR-Egger, weighted median, and weighted mode methods were used to estimate the causal effects. Multivariable MR analysis was performed to test whether the effects of childhood BMI on adult traits are independent from adult BMI.

Results

We identified potential causal effects of childhood obesity on 60 adult traits (27 disease-related traits, 27 lifestyle factors, and 6 other traits). Higher childhood BMI was associated with a reduced overall health rating (β = − 0.10, 95% CI − 0.13 to − 0.07, P = 6.26 × 10⁻¹¹). Specifically, higher childhood BMI was associated with increased odds of coronary artery disease (OR = 1.09, 95% CI 1.06 to 1.11, P = 4.28 × 10⁻¹¹), essential hypertension (OR = 1.12, 95% CI 1.08 to 1.16, P = 1.27 × 10⁻¹¹), type 2 diabetes (OR = 1.36, 95% CI 1.30 to 1.43, P = 1.57 × 10⁻³⁴), and arthrosis (OR = 1.09, 95% CI 1.06 to 1.12, P = 8.80 × 10⁻⁹). However, after accounting for adult BMI, the detrimental effects of childhood BMI on disease-related traits were no longer present (P > 0.05). For dietary habits, different from conventional understanding, we found that higher childhood BMI was associated with low calorie density food intake. However, this association might be specific to the UK Biobank population.

Conclusions

In summary, we provided a phenome-wide view of the effects of childhood BMI on adult traits. Multivariable MR analysis suggested that the associations between childhood BMI and increased risks of diseases in adulthood are likely attributed to individuals remaining obese in later life. Therefore, ensuring that childhood obesity does not persist into later life might be useful for reducing the detrimental effects of childhood obesity on adult diseases.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13073-021-00865-3.

Bidirectional temporal relationship between obesity and hyperinsulinemia: longitudinal observation from a Chinese cohort

INTRODUCTION

Although obesity and hyperinsulinemia are closely intercorrelated, their temporal sequence is still uncertain. This study aims to investigate the temporal relationship patterns between obesity measures and hyperinsulinemia in Chinese adults.

RESEARCH DESIGN AND METHODS

The longitudinal cohort consisted of 2493 participants (860 males and 1633 female, mean age 56.71 years at follow-up) for whom measurements of obesity and hyperinsulinemia measures were collected twice between 2011 and 2014, with an average follow-up time of 3 years. Cross-lagged panel analysis was used to examine the temporal relationship between obesity measures (body mass index (BMI); waist circumference (WC); hip circumference (HC); waist-to-hip ratio (WHR)) and hyperinsulinemia (insulin, homeostasis model assessment of insulin resistance (HOMA-IR), or homeostasis model assessment of beta cell function (HOMA-%β)).

RESULTS

After the adjustment of age, sex, smoking, drinking and follow-up years, in the BMI-insulin model, the path coefficient (β₂=0.229; p<0.001) of baseline BMI to follow-up insulin was significantly greater than the path coefficient (β₁=0.073; p<0.001) of baseline insulin to follow-up BMI (p<0.001 for β₂>β₁). In the WHR-insulin model, the path coefficient (β₁=0.152; p<0.001) of baseline insulin to follow-up WHR was significantly greater than the path coefficient (β₂=0.077; p<0.001) of baseline WHR to follow-up insulin (p=0.007 for β₁>β₂). In the WC/HC-insulin model, the path coefficients of baseline insulin to follow-up WC or HC (β_1s) were also greater than the path coefficients of baseline WC or HC to follow-up insulin (β_2s), but the difference between β_1s and β_2s were not significant. The similar temporal patterns were founded between obesity measures with HOMA-IR or HOMA-%β.

CONCLUSIONS

These findings indicate that there is a bidirectional relationship between obesity and hyperinsulinemia, and abdominal obesity measures are more sensitive to hyperinsulinemia measures than BMI.

Blood Pressure Tracking From Childhood to Adulthood

Hypertension is the most common non-communicable disease among adults and is the most important modifiable risk factor for premature cardiovascular disease. The increasing worldwide burden of hypertension is a major global health issue. Early prevention with lifestyle modification or pharmaceutical treatment reduces the incidence of hypertension and the risk of subsequent cardiovascular disease. Therefore, identification of young persons at risk for hypertension has the obvious benefit of providing a chance for early intervention. Previous studies have demonstrated the positive association of elevated childhood blood pressure with hypertension in adulthood. Accumulated evidence also indicates the possibility that elevated pediatric blood pressure is associated with increased risk of future cardiovascular disease. In this article, we review the tracking of blood pressure from childhood to adulthood and emphasize the importance of pediatric blood pressure monitoring and control for predicting and preventing adult hypertension and cardiovascular disease.

Novel loci for childhood body mass index and shared heritability with adult cardiometabolic traits

The genetic background of childhood body mass index (BMI), and the extent to which the well-known associations of childhood BMI with adult diseases are explained by shared genetic factors, are largely unknown. We performed a genome-wide association study meta-analysis of BMI in 61,111 children aged between 2 and 10 years. Twenty-five independent loci reached genome-wide significance in the combined discovery and replication analyses. Two of these, located near NEDD4L and SLC45A3, have not previously been reported in relation to either childhood or adult BMI. Positive genetic correlations of childhood BMI with birth weight and adult BMI, waist-to-hip ratio, diastolic blood pressure and type 2 diabetes were detected (Rg ranging from 0.11 to 0.76, P-values <0.002). A negative genetic correlation of childhood BMI with age at menarche was observed. Our results suggest that the biological processes underlying childhood BMI largely, but not completely, overlap with those underlying adult BMI. The well-known observational associations of BMI in childhood with cardio-metabolic diseases in adulthood may reflect partial genetic overlap, but in light of previous evidence, it is also likely that they are explained through phenotypic continuity of BMI from childhood into adulthood.

SOCS3 methylation mediated the effect of sedentary time on type 2 diabetes mellitus: The Henan Rural Cohort study

BACKGROUND AND AIMS

To assess the associations of sedentary time, suppressor of cytokine signaling (SOCS)-3 DNA methylation with type 2 diabetes mellitus (T2DM), and further identify the role of SOCS3 methylation in mediating the association of sedentary time with T2DM in a Chinese rural population.

METHODS AND RESULTS

A case-control study including 1032 participants from the Henan Rural Cohort study was conducted. Restricted cubic spline analysis and logistic regression model were performed to evaluate the associations between sedentary time, SOCS3 methylation and T2DM. The mediation effect of SOCS3 methylation on the association between sedentary time and T2DM was assessed. Sensitivity analysis was conducted by excluding individuals with diagnosed T2DM. Linear dose-response relationships were found between sedentary time, methylation level of Chr17:76356190 (one novel site on SOCS3) and T2DM. Compared with the first quartile (less than 5 h/d) of sedentary time, the adjusted odds ratio (OR, 95% confidence interval, 95%CI) for those in the third (7-10 h/d) and fourth (≥10 h/d) quartiles were 1.87 (1.22-2.85) and 3.54 (2.14-5.85), respectively. Participants in the fourth quartile of methylation level of Chr17:76356190 had lower risk of T2DM than those in the first quartile (OR (95%CI): 0.23 (0.14-0.38)). Mediation analysis showed 9.66% (6.38%-14.80%) of the association between sedentary time and T2DM was attributable to Chr17:76356190. The comparable effect estimates were observed between sedentary time, methylation level of Chr17:76356190 and undiagnosed T2DM.

CONCLUSION

Sedentary time and methylation level of Chr17:76356190 were both independently associated with T2DM in the Chinese rural population. Furthermore, Chr17:76356190 appeared to partially mediate the effect of sedentary time on T2DM.

CHINESE CLINICAL TRIAL REGISTRATION

ChiCTR-OOC-15006699 (URL: http://www.chictr.org.cn/showproj.aspx?proj=11375).

The role of childhood BMI in predicting early adulthood dysglycemia: Tehran lipid and glucose study

BACKGROUND AND AIM

Increased adiposity is associated with insulin resistance and glycemic disturbances. We aimed to determine whether childhood overweight or obesity are independent factors in predicting adulthood dysglycemia (prediabetes or type 2 diabetes).

METHODS AND RESULTS

In this population-based cohort study, 1290 normoglycemic subjects aged 3-11 years were followed for incidence of dysglycemia. Cox-proportional hazard models were employed to evaluate the association of obesity and overweight with incidence of dysglycemia by adjustments for age, sex, parental risk factors and baseline individual risk factors. The participants, with a mean age of 7.7 ± 2.5 years, were followed for a median of 14.9 years. During follow up, 158 subjects developed dysglycemia (18 type 2 diabetes, 140 prediabetes), contributing to a total cumulative incidence of 24.7%. The unadjusted HR for developing adult dysglycemia were 1.6 (95% CI; 1.0-2.4) and 1.7 (95% CI; 1.0-3.0) in overweight and obese children, respectively. Further adjustments for age, sex, parental risk factors and baseline individual risk factors changed the results in both overweight and obese children.

CONCLUSION

These findings show that overweight or obesity in childhood have no independent role for developing adulthood dysglycemia.

Temporal relationship between body mass index and triglyceride-glucose index and its impact on the incident of hypertension

BACKGROUND AND AIMS

Obesity and insulin levels can influence each other by metabolism. However, their temporal sequences and influence on hypertension are generally unknown, especially in Chinese adults. Recently, some scholars have proposed that triglycerides-glucose index (TyG) is an important indicator of insulin resistance. The study aims to describe the relationship between body mass index (BMI) and TyG index and its impact on hypertension.

METHODS AND RESULTS

A total of 4081 adults (56.33% women) without antihypertensive, hypoglycemic or lipid-lowering medications were selected for the present study. Measurements of BMI and TyG index were obtained twice from 2012 to 2017. Cross-lagged panel analysis was used to describe the temporal sequences between BMI and TyG index, and the effect of their temporal relationship patterns on hypertension was explored through mediation analysis. After adjusting for confounding factors (age, sex, ethnicity et al.), the cross-lagged path coefficient from baseline BMI to follow-up TyG (ρ₂ = 0.135, P < 0.001) was significantly greater than the path coefficient from baseline TyG to follow-up BMI (ρ₁ = 0.043, P < 0.001), and P < 0.001 for the difference between ρ₁ and ρ₂. Furthermore, the sensitivity analyses between women and men revealed identical findings. In addition, TyG index mediation effect on BMI-hypertension was estimated to be 38.45% (P < 0.001) in total population, 25.24% in women and 57.35% in men.

CONCLUSION

These results provided evidence that the temporal relationship between BMI and insulin resistance is reciprocal and a higher BMI precedes hyperinsulinemia in Chinese adults. This relationship plays an essential role in the development of hypertension, while there is a difference between women and men.

Associations of Cell Phone Use and Screen Viewing with Overweight in Children

Background: Effects of using mobile devices on childhood obesity have not been well studied. We aimed to ascertain whether cell phone use and screen viewing are associated with excess body weight in a cross-sectional study of Japanese school children. Methods: Subjects were 3141 students, ages 6 to 7 years, who participated in the Hekinan Children's Study conducted during 2011-2015. Participants were asked to submit a parent-administered questionnaire on child and parent demographics, health status, and lifestyles, including cell phone use and screen time. Heights and weights were measured at the schools. Being overweight was defined according to the cutoff point for children specified by the Extended International Obesity Task Force. Among 2596 analytic children, the odds ratios (ORs) for being overweight were estimated according to cell phone use, time spent watching television, and time spent on games and computers using the logistic regression models. Analyses were conducted after adjustments for potential confounders, including dietary intake, physical activities, sleep duration, and quality of sleep. Results: After multivariate adjustments, cell phone users were found to have an OR of 1.74 for being overweight compared with nonusers. Cell phone use of longer duration was associated with higher risk of being overweight (trend p = 0.018). Time spent watching television was positively associated with the risk of being overweight (trend p = 0.003). Conclusions: Just as earlier studies have shown for television viewing, cell phone use might be a risk factor related to being overweight among children.

The Hekinan Children's Study: Design and Profile of Participants at Baseline

BACKGROUND

The early life environment is now recognized as a key factor contributing to susceptibility to certain diseases in later life.

METHODS

We initiated a cohort study among school children in 2011 to primarily investigate the associations between lifestyle and environmental factors and some surrogate markers of chronic diseases, such as cardiometabolic risk factors (ie, obesity, high blood pressure, high blood glucose, insulin, or lipids) and cancer risk factors (ie, height and age at menarche). A baseline questionnaire asked for information, including demographic variables, medical history and use of medication, dietary habits, physical activity, sleep habits, and behavioral and emotional problems of children. Follow-up surveys are planned for the fourth grade of elementary school and the first grade of junior high school. At these follow-up surveys, fasting blood samples will be obtained to measure cardiometabolic markers. We also checked the validity of a food frequency questionnaire, which was originally created for 6-year-olds but was modified for use in older children.

RESULTS

A total of 3,141 first-year students at elementary schools in Hekinan City, Aichi Prefecture, participated in the study. The response rate was 87.4%. The means of age and body mass index were 6.99 (standard deviation, 0.28) years and 15.3 (standard deviation, 1.7) kg/m2, respectively, in the 3,067 Japanese children (1,639 boys and 1,428 girls).

CONCLUSIONS

This cohort will reveal determinants of cardiometabolic risk factors and cancer risk factors during childhood.

Shared genetic underpinnings of childhood obesity and adult cardiometabolic diseases

Background

Obesity during childhood can lead to increased risk of adverse cardiometabolic diseases such as type 2 diabetes and coronary artery disease during adult life. Evidence for strong genetic correlations between child and adult body mass index (BMI) suggest the possibility of shared genetic effects. We performed a test for pleiotropy (shared genetics) and functional enrichment of single nucleotide polymorphisms (SNPs) associated with childhood BMI and 15 adult cardiometabolic traits using a unified statistical approach that integrates pleiotropy and functional annotation data.

Results

Pleiotropic genetic effects were significantly abundant in 13 out of 15 childhood BMI-adult cardiometabolic trait tests (P < 3.3 × 10⁻³). SNPs associated with both childhood BMI and adult traits were more likely to be functionally deleterious than SNPs associated with neither trait. Genetic variants associated with increased childhood obesity tend to increase risk of cardiometabolic diseases in adulthood. We replicated 39 genetic loci that are known to be associated with childhood BMI and adult traits (coronary artery disease, HDL cholesterol, myocardial infarction, triglycerides, total cholesterol, type 2 diabetes, BMI, waist circumference, and waist-to-hip ratio) in previous genome-wide association studies. We also found a novel association of rs12446632 near GPRC5B, which is highly expressed in adipose tissue and the central nervous system, with adult HDL cholesterol.

Conclusions

This study found significant pleiotropic genetic effects and enrichment of functional annotations in genetic variants that were jointly associated with childhood obesity and adult cardiometabolic diseases. The findings provide new avenues to disentangle the genetic basis of life course associations between childhood obesity and adult cardiometabolic diseases.

Electronic supplementary material

The online version of this article (10.1186/s40246-019-0202-x) contains supplementary material, which is available to authorized users.

Body shape trajectories and the incidence of hypertension in a Mediterranean cohort: The sun study

AIMS

Our aim was to assess the association between trajectories of body-shape across the first 40 years of life and subsequent development of hypertension in a Mediterranean cohort.

METHODS AND RESULTS

We used a group-based modeling approach to assess body shape trajectories from age 5 to 40 years, among 7514 participants included in the SUN study (1999-2016), and assessed the subsequent incidence of hypertension. To create the trajectories, we used a censored normal model as a polynomial function of age. Cox models were used to estimates hazard ratios (HR) for hypertension according to body shape trajectories. Identified trajectories were "childhood lean -mid-life increase", "childhood medium-mid-life stable", " childhood heavy -mid-life decrease", and "childhood heavy -mid-life increase" for women; and "childhood lean-mid-life increase", "childhood medium-mid-life stable", "childhood medium -mid-life increase" and "childhood heavy-mid-life stable" for men. After a follow-up of 63,068 person-years, 865 incident cases of hypertension were found. Among women, compared to those in the "childhood medium-mid-life stable" trajectory, those, in the "childhood heavy -mid-life increase" trajectory showed higher risk to develop hypertension [HR = 1.72 (1.17-2.53)]. In men, compared with those in the "childhood medium-mid-life stable" trajectory, those in the "childhood lean and childhood medium -mid-life increase" and the "childhood heavy- mid-life stable" trajectories showed higher subsequent incidence of hypertension [HR = 1.43 (1.11-1.85), HR = 1.52 (1.17-1.97) and HR = 1.56 (1.14-2.14), respectively] after adjusting for potential confounders (including age, lifestyles, dietary intake, personality traits, physical activity and sedentary behaviors).

CONCLUSIONS

Our results suggest that mid-life increases in body shape or maintaining a heavy body shape during early and middle life in men and childhood heavy-mid-life increase in women is associated with a higher subsequent risk of developing hypertension in this Mediterranean population.

Association of Blood Pressure Trajectories in Early Life with Subclinical Renal Damage in Middle Age

BACKGROUND

Although high BP is one of the most important factors affecting renal function, whether longitudinal BP trajectories in early life course are associated with renal function damage in later life is unclear.

METHODS

To investigate the correlation between BP trajectories from childhood to adulthood and renal function in middle age, we used group-based trajectory models to identify BP trajectories in 2430 individuals (aged 6-15 years old at baseline) participating in the ongoing Hanzhong Adolescent Hypertension Cohort. We tested the association between these trajectories and subclinical renal damage in middle age, adjusting for several covariates.

RESULTS

We identified four distinct systolic BP trajectories among 2430 subjects: low stable, moderate stable, high stable, and moderate increasing on the basis of systolic BP levels at baseline and during the 30-year follow-up period. The urinary albumin-to-creatinine ratio (uACR) was higher in moderate stable, high stable, and moderate increasing groups compared with the low stable group. A total of 228 individuals had subclinical renal disease by 2017. Compared with the low stable trajectory group, the other groups had increasingly greater odds of experiencing subclinical renal disease in middle age. These associations were not altered after adjustment for other covariates, except for in the moderate stable group. Analyzed results were similar for the mean arterial pressure and diastolic BP trajectory groups.

CONCLUSIONS

Higher BP trajectories were correlated with higher of uACR levels and risk of subclinical renal disease in middle age. Identifying long-term BP trajectories from early age may assist in predicting individuals' renal function in later life.

Impact of cigarette smoking on the relationship between body mass index and insulin: Longitudinal observation from the Bogalusa Heart Study

OBJECTIVES

Despite the inverse association between cigarette smoking and body mass index (BMI), it is unknown whether the effect of smoking on insulin is mediated through decreased BMI. This study aims to examine the temporal relationship between BMI and insulin, the impact of smoking on this relationship and the mediation effect of BMI on the association between smoking and insulin levels.

METHODS

The longitudinal cohort consisted of 1121 adults (807 white and 314 black participants, mean age, 42.0 years at follow-up) for whom BMI and fasting insulin were measured twice, with an average follow-up period of 17.1 years. Cross-lagged panel and mediation analysis models were used to examine the temporal relationship between BMI and insulin, and the mediation effect of BMI on the smoking-insulin association.

RESULTS

Smoking was inversely associated with insulin (regression coefficient, -0.073; P = .015 at baseline and -0.121; P < .001 at follow-up), adjusting for age, race and gender. After additional adjustment for follow-up periods, the cross-lagged path coefficient from BMI to insulin (β, 0.226; P < .001) was significantly greater than that from insulin to BMI (β, -0.029; P = .208), with P < .001 for the difference. The path coefficient from BMI to insulin was significantly greater in non-smokers (β, 0.273; P < .001) than in smokers (β, 0.122; P = .046), with P = .013 for the difference. The mediation effect of BMI on the smoking-insulin association was estimated at 53.4% (P = .030) at baseline and 58.7% (P < .001) at follow-up.

CONCLUSIONS

These findings suggest that cigarette smoking has a significant impact on the one-directional relationship from BMI to insulin. The insulin-lowering effect of smoking is predominantly mediated through decreased BMI as the result of smoking.

Childhood BMI and Adult Type 2 Diabetes, Coronary Artery Diseases, Chronic Kidney Disease, and Cardiometabolic Traits: A Mendelian Randomization Analysis

OBJECTIVE

To test the causal effect of childhood BMI on adult cardiometabolic diseases using a Mendelian randomization analysis.

RESEARCH DESIGN AND METHODS

We used 15 single nucleotide polymorphisms as instrumental variables for childhood BMI to test the causal effect of childhood BMI on cardiometabolic diseases using summary-level data from consortia.

RESULTS

We found that a 1-SD increase in childhood BMI (kg/m²) was associated with an 83% increase in risk of type 2 diabetes (odds ratio [OR] 1.83 [95% CI 1.46, 2.30]; P = 2.5 × 10^-7) and a 28% increase in risk of coronary artery disease (CAD) (OR 1.28 [95% CI 1.17, 1.39]; P = 2.1 × 10^-8) at the Bonferroni-adjusted level of significance (P < 0.017) in adults. In addition, a 1-SD increase in childhood BMI was associated with a 0.587-SD increase in adulthood BMI (kg/m²), a 0.062-SD increase in hip circumference (cm), a 0.602-SD increase in waist circumference (cm), a 0.111 pmol/L increase in log fasting insulin, a 0.068 increase in log-transformed HOMA of ß-cell function (%), a 0.126 increase in log-transformed HOMA of insulin resistance (%), and a 0.109-SD increase in triglyceride (mg/dL) but a 0.138-SD decrease in HDL (mg/dL) in adults at the Bonferroni-adjusted level of significance (P < 0.0026).

CONCLUSIONS

A genetic predisposition to higher childhood BMI was associated with increased risk of type 2 diabetes and CAD in adult life. These results provide evidence supportive of a causal association between childhood BMI and these outcomes.

Temporal relationship between hyperuricemia and obesity, and its association with future risk of type 2 diabetes

BACKGROUND/OBJECTIVES

Although hyperuricemia and obesity are significantly correlated, their temporal relationship and whether this relationship is associated with future risk of diabetes are largely unknown. This study examined temporal relationship between hyperuricemia and obesity, and its association with future risk of type 2 diabetes.

SUBJECTS/METHODS

This study examined two longitudinal cohorts totally including 17,044 subjects from China with an average of 6.0 years follow-up. Measurements of body mass index (BMI), waist circumference (WC), percentage of body fat and fasting serum uric acid were obtained at two time points. Cross-lagged panel and mediation analysis were used to examine the temporal relationship between hyperuricemia and obesity, and the association of this temporal relationship with follow-up diabetes.

RESULTS

In combined data of the two cohorts, the cross-lagged path coefficient (β₁ = 0.121; 95% confidence interval (CI): 0.108-0.135) from baseline uric acid to the follow-up BMI was significantly greater than the path coefficient (β₂ = 0.055, 95% CI: 0.038-0.072) from baseline BMI to the follow-up uric acid (P = 8.14e^-10 for the difference between β₁ and β₂) with adjustment for covariates. The separate cross-lagged path models of uric acid with WC and percentage of body fat showed temporal patterns similar to that noted for uric acid with BMI. Further, the path coefficient (β₁) from baseline uric acid to follow-up BMI in the group with diabetes was significantly greater than without diabetes (P = 0.003 for the difference of β₁s in the two groups). BMI partially mediated the association of uric acid with risk of diabetes, and the percentage of mediated-association was estimated at 20.3% (95% CI: 15.7-24.8%). Results of these analyses in the combined data were consistent with those in the two cohorts, respectively.

CONCLUSIONS

These findings indicated that increased uric acid levels probably associated with obesity and type 2 diabetes, and more definite research is needed to define any role for uric acid in relation to these diseases.

The Evolving Epidemiology of Atherosclerotic Cardiovascular Disease in People with Diabetes

Atherosclerotic cardiovascular disease (ASCVD) is a leading global cause of death and accounts for most deaths among individuals with diabetes. This article reviews the latest observational and trial data on changes in the relationship between diabetes and ASCVD risk, remaining gaps in how the role of each risk factor is understood, and current knowledge about specific interventions. Differences between high-income countries and low-income and middle-income countries are examined, barriers and facilitators are discussed, and a discussion around the concept of ideal cardiovascular health factors (Life's Simple 7) is focused on.

Temporal Relationship Between Hyperuricemia and Insulin Resistance and Its Impact on Future Risk of Hypertension

Although hyperuricemia and insulin resistance significantly correlated, their temporal sequence and how the sequence influence on future risk of hypertension are largely unknown. This study assessed temporal relationship between uric acid and insulin resistance and its impact on future risk of hypertension by examining a longitudinal cohort including 8543 subjects aged 20 to 74 years from China, with an average follow-up of 5.3 years. Measurements of fasting uric acid, as well as fasting and 2-hour serum glucose and insulin, were obtained at baseline and follow-up. Indicators of hepatic and peripheral insulin resistance were calculated. Cross-lagged panel and mediation analysis were used to examine the temporal relationship between uric acid and insulin resistance and its impact on follow-up hypertension. After adjusting for covariates, the cross-lagged path coefficients (β₁ values) from baseline uric acid to follow-up insulin resistance indices were significantly greater than path coefficients (β₂ values) from baseline insulin resistance indices to follow-up uric acid (β₁=0.110 versus β₂=0.017; P<0.001, for hepatic insulin resistance; β₁=-0.208 versus β₂=-0.021; P<0.001, for peripheral insulin resistance). The path coefficients from baseline uric acid to follow-up insulin resistance indices in the hypertensive group were significantly greater than that in the normotensive group (P<0.001 for the difference of β₁ values in the 2 groups). Insulin resistance partially mediated the effect of uric acid on subsequent hypertension, and the mediation effect of peripheral insulin resistance was significantly greater than that of hepatic insulin resistance (31.3% versus 13.2%; P<0.001, for the difference of mediation effects). These findings provide evidence that higher uric acid levels probably precede insulin resistance, and peripheral insulin resistance likely plays a more important role in the development of hypertension than hepatic insulin resistance does.

Gene-Diet Interaction and Precision Nutrition in Obesity

The rapid rise of obesity during the past decades has coincided with a profound shift of our living environment, including unhealthy dietary patterns, a sedentary lifestyle, and physical inactivity. Genetic predisposition to obesity may have interacted with such an obesogenic environment in determining the obesity epidemic. Growing studies have found that changes in adiposity and metabolic response to low-calorie weight loss diets might be modified by genetic variants related to obesity, metabolic status and preference to nutrients. This review summarized data from recent studies of gene-diet interactions, and discussed integration of research of metabolomics and gut microbiome, as well as potential application of the findings in precision nutrition.

Long-term Impact of Temporal Sequence from Childhood Obesity to Hyperinsulinemia on Adult Metabolic Syndrome and Diabetes: The Bogalusa Heart Study

This study aims to delineate the temporal relations between body mass index (BMI) and insulin in childhood and their impact on adult metabolic syndrome (MetS) and type 2 diabetes mellitus (T2DM).The longitudinal cohort consisted of 609 whites and 339 blacks who had BMI and fasting insulin measured twice in childhood (mean age = 10.5 years at baseline and 15.9 years at follow-up). Incident MetS and T2DM were identified in adulthood (mean age = 30.5 years). Cross-lagged panel and mediation analysis models were used. After adjusting for age, race, gender, and follow-up years, the cross-lagged path coefficient of BMI → insulin (β = 0.326, p < 0.001) was significantly greater than that of insulin → BMI (β = −0.023, p = 0.207) in childhood, with p < 0.001 for the difference in βs. The path coefficient for BMI → insulin was significantly greater in MetS than in non-MetS groups (0.510 vs 0.190, p < 0.001), and greater in hyperglycemia than in normoglycemia groups (0.503 vs 0.285, p = 0.026). The mediation effect of childhood insulin on the BMI-MetS and BMI-hyperglycemia associations was estimated at 19.2% (p < 0.001) and 18.3% (p < 0.001), respectively. These findings provide evidence that higher BMI levels precede hyperinsulinemia during childhood, and this one-directional relation plays a significant role in the development of MetS and T2DM in adult life.