Familial aggregation of bone mineral density and bone mineral content in a Chinese population

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 acknowledgment 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 ≥ 15.02 μmo/L. Four groups were analyzed, using COX proportional hazard regression model, separately and pairwise to observe the independent 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 < 15.02 μmo/L (low tHcy), those with tHcy ≥ 15.02 μmo/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 borderline ABI and tHcy. More attention should be given to the importance of borderline ABI in hypertensive population, especially with elevated tHcy level.

Total bone mineral density is inversely associated with stroke: a family osteoporosis cohort study in rural China

BACKGROUND

The relationship of osteoporosis and stroke is still not fully clarified. Apart from the well-known risk factors for stroke, bone mineral density (BMD) has gained more interest in recent years.

AIM

To further elucidate the relationship between BMD and stroke risk, a prospective cohort study in the Chinese rural population was conducted.

DESIGN

Retrospective analysis of a family osteoporosis cohort.

METHODS

Our subjects were selected from an osteoporosis cohort conducted in Anqing, China. All participants underwent a questionnaire assessment, clinical examinations and laboratory assessments. During the follow-up period, the number of people who had a stroke was recorded. Generalized estimating equation regression analysis was performed to determine the significance of the association between BMD and stroke.

RESULTS

A total of 17868 people were included. A two-way interaction test of sex and BMD on stroke was significant (P = 0.002). There was a significant difference in BMD and stroke morbidity in the male group (P = 0.003). When BMD was assessed as quartiles and the lowest quartile was used as reference, a significantly lower risk for stroke was observed in Q2-4. Notably, no significant difference was observed in female participants with adjusted odds ratio (P > 0.05). The P-value for interaction was calculated. The body mass index (P = 0.014) and waist-to-hip ratio (P = 0.027) were found to be significantly associated with BMD and stroke risk in female participants.

CONCLUSIONS

In Chinese rural areas, total BMD may negatively correlated with stroke, especially in men.

Effect of fasting blood glucose on risk of new-onset hypertension in rural Chinese population: a 15-year follow-up cohort

BACKGROUND

The purpose of this study was to examine the correlation between fasting blood glucose and new-onset hypertension and examine any synergistically effect modification with multiple risk factors.

METHODS

We conducted post-hoc analyses of repeated-measures data in the original Dongzhi osteoporosis cohort study. In total, 3985 participants without hypertension aged 25-64 years were included in the current analyses. Generalized estimating equation models were used to assess the relationship between fasting blood glucose and risk of new-onset hypertension after adjusting for pertinent covariates and autocorrelations among siblings.

RESULTS

393 men (19.4%) and 398 women (20.3%) without hypertension at the baseline developed hypertension by the end of the study period. Compared to lower baseline fasting blood glucose levels (Q1-Q3: < 5.74 mmol/L; clinical cut points: < 5.6 mmol/L), higher baseline fasting blood glucose levels (Q4: ≥ 5.74 mmol/L; clinical cut points: ≥ 5.6 mmol/L and < 7.0 mmol/L) increased the risk of new-onset hypertension significantly [(OR: 1.54, 95% CI 1.19-1.98, P < 0.001); (OR: 1.38, 95% CI 1.09-1.75, P = 0.008)] in women. Additionally, a stronger significant association was found in women with elevated fasting blood glucose on risk of new-onset of hypertension with higher total cholesterol (≥ 5.2 mmol/L) [(OR: 2.76; 95% CI: (1.54, 4.96), P < 0.001)]. However, no association was found between fasting blood glucose and risk of new-onset hypertension in men.

CONCLUSIONS

High fasting blood glucose may be significantly associated with risk of new-onset hypertension in Chinese women, especially in women with higher total cholesterol. Further randomized studies are needed to confirm our findings.

Inverse association between body mass index and all-cause mortality in rural chinese adults: 15-year follow-up of the Anqing cohort study

OBJECTIVE

To investigate the association between body mass index (BMI) and all-cause mortality in a Chinese rural population.

DESIGN

Prospective cohort study.

SETTING

This study was conducted from 2003 to 2018 in Anqing, Anhui Province, China.

PARTICIPANTS

17 851 participants aged 25-64 years (49.4% female) attending physical examinations and questionnaire were included in this study. The inclusion criterion was families having a minimum of three participating siblings. The exclusion criteria included participants without family number and BMI data at baseline.

OUTCOME MEASURES

The outcome measure was all-cause mortality. Generalized estimating equation (GEE) regression analysis was performed to determine the association between baseline BMI and all-cause mortality.

RESULTS

During a mean follow-up period of 14.1 years, 730 deaths (8.0%) occurred among men, and 321 deaths (3.6%) occurred among women. The mean BMI for males was 21.3[Formula: see text] kg/m², and for female it was 22.1±3.1 kg/m². Baseline BMI was significantly inversely associated with all-cause mortality risk for per SD increase (OR, 0.79 (95% CI, 0.72 to 0.87) for males; OR, 0.88 (95% CI, 0.76 to 1.01) for females). When BMI was stratified with cut points at 20 and 24 kg/m², compared with the low BMI group, a significantly lower risk of death was found in the high BMI group (BMI ≥24: OR, 0.57 (95% CI, 0.43 to 0.77) in males; 0.65 (95% CI, 0.46 to 0.93) in females) after adjustment for relevant factors.

CONCLUSIONS

In this relatively lean rural Chinese population, the risk of all-cause mortality decreased with increasing BMI. The excess risk of all-cause mortality associated with a high BMI was not seen among this rural population.

Cigarette smoking and all-cause mortality in rural Chinese male adults: 15-year follow-up of the Anqing cohort study

Background

According to the Global Burden of Disease Study 2017, smoking is one of the leading four risk factors contributing to deaths in China. We aimed to evaluate the associations of smoking with all-cause mortality in a Chinese rural population.

Methods

Male participants over age 45 (n = 5367) from a large familial aggregation study in rural China, were included in the current analyses. A total of 528 former smokers and 3849 current smokers accounted for 10 and 71.7% of the cohort, respectively. Generalized Estimating Equations were used to evaluate the association between baseline smoking status and mortality, adjusting for pertinent covariates.

Results

There were 579 recorded deaths during the 15-year follow-up. Current smokers (odds ratio [OR],1.60; 95% CI,1.23–2.08) had higher all-cause mortality risks than nonsmokers. Relative to nonsmokers, current smokers of more than 40 pack-years ([OR],1.85; 95% CI,1.33–2.56) had a higher all-cause mortality risk. Compared to nonsmokers, current smokers who started smoking before age 20 ([OR],1.91; 95% CI,1.43–2.54) had a higher all-cause mortality risk, and former smokers in the lower pack-year group who quit after age 41 (median) ([OR],3.19; 95% CI,1.83–5.56) also had a higher risk of death after adjustment. Furthermore, former smokers who were also former drinkers had the highest significant risk of mortality than never smokers or drinkers. (P for interaction = 0.034).

Conclusions

This study provides evidence that current smokers and former smokers have a higher mortality risk than nonsmokers and would benefit from cessation at a younger age.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12889-021-10691-2.

Association Between Fasting Blood Glucose and All-Cause Mortality in a Rural Chinese Population: 15-Year Follow-Up Cohort Study

INTRODUCTION

The worldwide prevalence of diabetes has been increasing for decades; diabetes can lead to serious health problems and even death, but the effects of maintaining low fasting blood glucose (FBG) remain controversial. The purpose of this study was to investigate the relationship between FBG levels and all-cause mortality in a long-term follow-up cohort and to find a relatively safe range of FBG levels.

METHODS

This study included 17,902 adults from a community-based cohort study in rural China who were prospectively followed from 2003 to 2018. Generalized estimating equations were used to evaluate the association between FBG and all-cause mortality, adjusting for pertinent covariates and auto-correlations among siblings.

RESULTS

A total of 1053 (5.9%) deaths occurred during 15 years of follow-up. There was a significant U-shaped association between all-cause mortality and FBG. Compared with the reference group (FBG of 5.6 - < 6.1 mmol/l), the risk of death among individuals with FBG levels < 5.6 mmol/l significantly increased by 38% (OR 1.34; 95% CI 1.13-1.59), while the risk of death among individuals with FBG ≥ 6.1 mmol/l or participants with a self-reported history of diabetes significantly increased by 51% (OR 1.49; 95% CI 1.20-1.85). Additionally, the U-shaped association remained steady in any stratification of risk factors.

CONCLUSION

Our study showed a significant U-shaped relationship between FBG levels and risk of all-cause mortality in this rural Chinese population. When FBG was within the range of 5.6 - < 6.1 mmol/l, the risk of all-cause mortality was the lowest.

Association between secreted phosphoprotein-1 (SPP1) polymorphisms and low bone mineral density in women

BACKGROUND

A recent meta-analysis found that secreted phosphoprotein-1 (SPP1) can predict the risk of both osteoporosis and fracture. No study has explored the association of SPP1 haplotype-tagging single nucleotide polymorphisms (htSNPs) and haplotypes with bone mineral density (BMD).

METHODS

This is a cross-sectional study. A total of 1,313 healthy Taiwanese women aged 40 to 55 years were recruited from MJ Health Management Institute from 2009 to 2010. BMD was dichotomized into high and low BMD groups. Three common (allele frequency ≥5%) htSNPs were selected to examine the association between sequence variants of SPP1 and BMD.

RESULTS

Homozygosity for the T allele of rs4754 were protective from low BMD [TT vs. CC: adjusted OR (AOR)  = 0.58, 95% confidence interval (CI)  = 0.83-0.89]. A protective effect was also found for women carrying 2 copies of Hap3 TCT (AOR  = 0.57, 95% CI  = 0.34-0.95). Menopausal status marginally interacted with SPP1 rs6839524 on BMD (p = 0.049). Postmenopausal women carrying variant rs6839524 (GG+GC vs. CC: AOR  = 2.35, 95% CI  = 1.06-5.20) or Hap1 TGC (AOR  = 2.36, 95% CI  = 1.06-5.24) were associated with 2.4-fold risk of low BMD. For women with low BMI (<18.5 kg/m2), variant rs6839524 (AOR  = 7.64) and Hap1 (AOR  = 6.42) were associated with increased risk of low BMD. These findings did not reach statistical significance after correction for multiple tests.

CONCLUSIONS

SPP1 htSNP protected against low BMD in middle-aged women. SPP1 genetic markers may be important for the prediction of osteoporosis at an early age.

Familial aggregation of forearm bone mineral density in Chinese

Osteoporosis is a major public health concern and its prevalence can be predicted based on forearm bone mineral density (BMD). This study is to investigate the familial aggregation of forearm BMD in a population-based, cross-sectional study in Anhui, China. Information on sociodemographic and environmental variables was obtained from 1,636 subjects from 409 nuclear families (including mother, father, and their first two children) by a standardized questionnaire. The forearm BMD was measured by peripheral dual-energy X-ray absorptiometry (pDXA). Using generalized additive models with a sequential adjustment for covariates, it was clearly indicated that the forearm BMD of the mother, the father, and the first sibling each had a significant and independent relation to the forearm BMD of the second sibling. Furthermore, using multiple logistic regression, the second sibling had an odds ratio (OR) of 5.3 (95%CI: 2.0-14.5) of having an extremely low (bottom 10th percentile) proximal forearm BMD and an OR of 4.3 (95%CI: 1.6-12.0) of having an extremely low distal forearm BMD when the parental mean forearm BMD was low and the first sibling's forearm BMD was low. Our findings showing strong familial aggregation of both proximal and distal forearm BMD values suggest that genetic factors play a significant role in determining both traits.