Is waist circumference a negative predictor of calcaneal bone mineral density in adult Chinese men with normal weight?

BACKGROUND: Our study aimed to evaluate the association between waist circumference (WC) and calcaneal bone mineral density (BMD) in adult Chinese men with normal weight. METHODS: This was a cross-sectional study. A total of 4,663 male participants aged 40 years or older residing in Ningde and Wuyishan, two cities locating in Fujian province of China, were randomly recruited between 2011 and 2012. Each participant should complete a standard questionnaire, undergo anthropometric and calcaneus quantitative ultrasound (QUS) measurements and have blood sample taken. Anthropometric, biochemical and calcaneal QUS parameters of 1,583 male participants with BMI ranging from 18.5 to 22.9 were included in the analysis. WC was divided into quartiles (Q1-Q4: <71, 71-75, 75-78, >78 cm). The relationship between WC (quartiles) and BMD was analyzed by multiple linear regression models. RESULTS: Mean age of the whole population was 54.6±9.8 years. Anthropometric and biochemical parameters were almost normal. Multiple linear regression analysis showed that BMD was negatively associated with increasing WC quartiles except for Q2 after adjusting for age and BMI, and this relationship remained negative except for Q2 when further adjustment was made for other covariates. Multiple logistic regression model also showed that the risks of osteopenia and osteoporosis increased across WC quartiles. CONCLUSIONS: The present study indicated that WC was a negative predictor of calcaneal BMD in adult Chinese men with normal weight. It suggests that, even for the normal-weight Asian males, monitoring accrual of abdominal adipose is still helpful for the purpose of preventing bone loss.

EXPOSURE TO FAMINE IN EARLY LIFE AND THE RISK OF OSTEOPOROSIS IN ADULTHOOD: A PROSPECTIVE STUDY.

Objective: To assess the association between famine exposure in early life and osteoporosis in adulthood. Methods: A total of 2,292 participants born between 1955 and 1965 in Fujian Province were selected; after 3 years, 1,378 participants attended a follow-up research visit. Calcaneus bone mineral density and bone quality were measured by quantitative ultrasound. The T-score was used to assess bone mineral density, and the parameters quantitative ultrasound index (QUI), speed of sound (SOS), and broadband ultrasonic attenuation (BUA) were used to assess bone quality. A T-score threshold of -1.8 was defined as osteoporosis, and a possible vertebral fracture was considered as a prospective height loss of 0.8 inches or more. Results: Compared with the nonexposed cohort, risks of osteoporosis for fetal-, early childhood, and mid-childhood famine-exposed cohorts in postmenopausal women were adjusted odds ratio (OR), 3.741 (95% confidence interval [CI], 1.233, 11.44) versus OR 2.894 (95% CI, 0.997, 8.571) versus OR 4.699 (95% CI, 1.622, 13.612) by logistic regression but not significant in men. Moreover, the fetal-exposed cohort had a weak negative relation with QUI (ß, -5.07 [-10.226, 0.127]) and BUA (ß, -4.321 [-0.88, 0.238]). The early- and mid-childhood-exposed cohorts had significantly lower QUI (ß, -7.085 [-11.799, -2.372] versus ß, -10.845 [-15.68, -6.01]) and BUA (ß, -6.381 [-10.515, -2.246] versus ß, -8.573 [-12.815, -4.331]) than the nonexposed cohort by linear regression. None of the famine-exposed cohorts had a significant relationship with SOS. Conclusion: Famine exposure during early life is associated with higher risk of osteoporosis in adulthood, which is most obvious in postmenopausal women. Furthermore, famine exposure in early life has adverse effects on bone quality. Abbreviations: BMD = bone mineral density; BUA = broadband ultrasonic attenuation; CI = confidence interval; OR = odds ratio; QUI = quantitative ultrasound index; QUS = quantitative ultrasound; SOS = speed of sound.

Early life exposure to famine and reproductive aging among Chinese women.

OBJECTIVE: To assess the effect of early life exposure to famine, as endured during 1959 to 1961 in China, on reproductive aging in adult women. METHODS: Between 2011 and 2012, 2,868 women born around the Chinese famine period (1956-1964) were enrolled in this study from three communities in China. Age at natural menopause was obtained retrospectively from a structured questionnaire. The associations of early life famine exposure with reproductive aging during adulthood were estimated, with adjustment of socioeconomic status, lifestyle factors, and body mass index. RESULTS: Women exposed to prenatal famine had a higher risk of early menopause (ie, natural menopause <45 years, odds ratio: 1.59, 95% confidence interval [CI]: 1.07, 2.36), and a nonsignificant trend of higher risk of premature ovarian failure (ie, natural menopause <40 y, odds ratio: 1.94, 95% CI: 0.93, 4.00), compared to unexposed women. Exposure to famine during childhood was not significantly associated with reproductive aging. In a secondary analysis focusing on the fetal exposure, prenatal famine exposure was associated with a higher risk of premature ovarian failure (odds ratio: 2.07, 95% CI: 1.08, 3.87), and a nonsignificant trend of higher risk of early menopause (odds ratio: 1.37, 95% CI: 0.98, 1.91), compared to those unexposed to prenatal famine. CONCLUSIONS: Our study showed that fetal exposure to famine was associated with an increased risk of early menopause. Such findings provided evidence in favor of the thrifty phenotype theory in reproductive aging and helped better understand the etiology of early menopause.

Association Between Bone Mineral Density and Pancreatic ß-Cell Function in Elderly Men and Postmenopausal Women.

PURPOSE: To explore the association between bone mineral density (BMD) and ß-cell function. METHODS: A cross-sectional study was performed in Fujian, China, from 2011 to 2012. The study included 572 elderly men older than age 60 years and 1558 postmenopausal women aged 45 to 86 years, excluding those with diabetes and insulin resistance. Fasting glucose and insulin concentrations were measured. Pancreatic ß-cell function was estimated by using the homeostasis model assessment (HOMA-ß). Calcaneus BMD was measured by using quantitative ultrasonography. Multiple regression analyses were applied to explore the association. RESULTS: Participants with decreased BMD had lower fasting glucose (P < 0.001 in postmenopausal women; P = 0.007 in elderly men) and greater HOMA-ß (P = 0.001 in postmenopausal women; P = 0.008 in elderly men) than those with normal BMD, whereas no statistical differences in insulin were seen among categories of BMD. After adjustment for all confounders, HOMA-ß was still significantly negatively related to BMD in both groups (all P < 0.001), and remarkable positive relationships were found between BMD and fasting glucose. Furthermore, binary logistic regression presented fully adjusted odds ratios for diabetes in those with osteoporosis vs those with normal BMD: 0.60 [95% confidence interval (CI), 0.38 to 0.94] and 0.66 (95% CI, 0.49 to 0.91) in the original selected population of elderly men (n = 1070) and postmenopausal women (n = 2825), respectively. CONCLUSIONS: BMD was independently inversely associated with HOMA-ß and positively associated with fasting glucose in both elderly men and postmenopausal women, suggesting that bone mass may be a predictor of glucose metabolism. Further research is needed to verify the associations and determine the exact mechanism underlying them.

Is Retinal Microvascular Abnormalities an Independent Risk Factor of Vertebral Fractures? A Prospective Study From a Chinese Population.

Low bone mineral density (BMD) and microvascular diseases (MVD) share various common risk factors; however, whether MVD is an independent risk factor of vertebral fractures is incompletely understood. The aim of this study is to clarify whether MVD is an independent risk factor of vertebral fractures. In this prospective study, calcaneal BMD and retinal microvascular abnormalities were assessed at baseline from June 2011 to January 2012. A total of 2176 premenopausal women, 2633 postmenopausal women, 2998 men aged <65 years, and 737 men aged ≥65 were included. Then with/without retinal microvascular abnormalities cohorts were followed for an average of 2.93 years to find out the relationship between MVD and vertebral fractures. At the baseline, after full adjustment, retinal microvascular abnormalities were related to risk of low BMD only in men aged ≥65 years (odds ratio [OR] = 2.506; 95% confidence interval [CI] 1.454-4.321; p = 0.001). After follow-up of 2.93 years, retinal microvascular abnormalities were related to risk of vertebral fractures in men aged ≥65 years (OR = 2.475; 95% CI 1.085-5.646; p = 0.031) when adjustment for confounding factors. However, no associations were found between MVD and vertebral fractures in men aged <65 years, premenopausal women, and postmenopausal women. When stratified by diabetes, in the without-diabetes group, the men with retinal microvascular abnormalities had higher risk for vertebral fractures than without retinopathy (OR = 2.194; 95% CI 1.097-4.389; p = 0.026); however, the difference was not found in women. In the diabetes group, there were no significant differences of risk for vertebral fractures between those with retinal microvascular abnormalities and those without both in men and women. Stratified by hypertension, the men with retinopathy had higher risk for vertebral fractures than those without among the hypertension group (OR = 2.034; 95% CI 1.163-3.559; p = 0.013), but a difference was not found among women. In the without-hypertension group, no relation was found between MVD and fracture both in men and women. In conclusion, MVD is an independent risk factor of vertebral fractures in old men. © 2017 The Authors. JBMR Plus is published by Wiley Periodicals, Inc. on behalf of the American Society for Bone and Mineral Research.

Associations between sleep duration, daytime nap duration, and osteoporosis vary by sex, menopause, and sleep quality.

CONTEXT: Associations between sleep, daytime nap duration, and osteoporosis remain uncertain, and far less is even known about the influence of sex, menopause, and sleep quality on them. OBJECTIVE: The objective of the study was to test the associations between sleep, daytime nap duration, and osteoporosis and whether they vary by sex, menopause, and sleep quality. DESIGN, SETTING, AND PATIENTS: This cross-sectional study was based on two communities in China. A total of 8688 participants (3950 males and 4738 females) aged 40 years or older were enrolled in the study. MAIN OUTCOMES MEASURES: Self-reported sleep duration, daytime nap duration, sleep quality, and calcaneus bone mineral density were recorded. RESULTS: Sleep duration of 8-9 h/d and nap duration of 0 min/d were regarded as reference values. In postmenopausal women, risks (odds ratio and 95% confidence interval) of osteoporosis for sleep durations of 7-8 h/d, 9-10 h/d, and 10 h/d or longer were 1.531 (1.106, 2.121), 1.360 (1.035, 1.787), and 1.569 (1.146, 2.149), respectively (P < .05), and risks of osteoporosis for daytime nap durations of 30-60 min/d and longer than 60 min/d were 1.553 (1.212-1.989) and 1.645 (1.250-2.165), respectively (P < .05). However, a significant difference was not consistently observed in men or premenopausal women, regardless of sleep or daytime nap duration. As for sleep quality, positive results were seen most remarkably in postmenopausal females with good sleep. CONCLUSIONS: Sleep durations of 7-8 h/d, 9-10 h/d, and 10 h/d or longer, as well as longer daytime napping times, tend to present higher risks of having osteoporosis, and this tendency is most obvious in postmenopausal women reporting good-quality sleep.

Associations of green tea and rock tea consumption with risk of impaired fasting glucose and impaired glucose tolerance in Chinese men and women.

OBJECTIVE: To explore the associations of green tea and rock tea consumption with risk of impaired fasting glucose (IFG) and impaired glucose tolerance (IGT). METHODS: A multistage, stratified, cluster, random-sampling method was used to select a representative sample from Fujian Province in China. In total, 4808 subjects without cardiovascular disease, hypertension, cancer, or pancreatic, liver, kidney, or gastrointestinal diseases were enrolled in the study. A standard questionnaire was used to gather data on tea (green, rock, and black) consumption and other relevant factors. The assessment of impaired glucose regulation (IGR) was using 75-g oral glucose tolerance test (OGTT), the diagnostic criteria of normal glucose tolerance was according to American Diabetes Association. RESULTS: Green tea consumption was associated with a lower risk of IFG, while rock tea consumption was associated with a lower risk of IGT. The adjusted odds ratios for IFG for green tea consumption of <1, 1-15, 16-30, and >30 cups per week were 1.0 (reference), 0.42 (95% confidence intervals (CI) 0.27-0.65), 0.23 (95% CI, 0.12-0.46), and 0.41 (95% CI, 0.17-0.93), respectively. The adjusted odds ratios for IGT for rock tea consumption of <1, 1-15, 16-30, and >30 cups per week were 1.0 (reference), 0.69 (95% CI, 0.48-0.98), 0.59 (95% CI, 0.39-0.90), and 0.64 (95% CI, 0.43-0.97), respectively. A U-shaped association was observed, subjects who consumed 16-30 cups of green or rock tea per week having the lowest odds ratios for IFG or IGT. CONCLUSIONS: Consumption of green or rock tea may protect against the development of type 2 diabetes mellitus in Chinese men and women, particularly in those who drink 16-30 cups per week.

Associations between age at menarche and menopause with cardiovascular disease, diabetes, and osteoporosis in Chinese women.

CONTEXT: Ages at menarche and menopause are associated with cardiovascular disease (CVD), diabetes, and osteoporosis in Caucasian women, but associations remain unexplored in Chinese women. OBJECTIVE: The purpose of this study was to assess associations between age at menarche and menopause with CVD, diabetes, and osteoporosis in Chinese women. DESIGN AND SETTING: A cross-sectional, population-based study was conducted in Fujian, China, from June 2011 to January 2012. PARTICIPANTS: Among 6242 women aged 21 to 92 years, 3304 postmenopausal women were enrolled, excluding premenopausal women (n = 2527), those with unreported ages at menarche and menopause (n = 138), those with unrecorded physical measurements (n = 203), and those with menarche age <8 years or >20 years (n = 70). MAIN OUTCOME MEASURES: An oral glucose tolerance test, a 12-lead resting electrocardiogram, and calcaneus quantitative ultrasound were performed. RESULTS: No significant associations were found between menarche age, diabetes, and osteoporosis (both P > .05); later menarche (>18 years) was significantly associated with lower CVD risk (odds ratio = 0.71, 95% confidence interval, 0.57-0.89; P = .002). Menopause age was not associated with diabetes; higher menopause age was associated with decreasing CVD risk (P for trend = .020) and earlier menopause (≤46 years) with significantly higher osteoporosis risk (odds ratio = 1.59, 95% confidence interval, 1.07-2.36; P = .023). CONCLUSIONS: In China, ages at menarche and menopause are not associated with diabetes. Later menarche and menopause are associated with decreasing CVD risk and earlier menopause with higher osteoporosis risk. Menarche and menopause history may help identify women with increased risk of developing CVD and osteoporosis.