Longevity Areas In China Research Articles

Association of urinary cadmium level with body mass index and body circumferences among older adults over 65 years old in 9 longevity areas of China

Objective: To investigate the association of urinary cadmium level with body mass index (BMI) and body circumferences among the older adults over 65 years old in 9 longevity areas of China. Methods: Subjects were older adults over 65 years old from the Healthy Aging and Biomarkers Cohort Study (HABCS) between 2017 and 2018 conducted in 9 longevity areas in China. A total of 1 968 older adults were included in this study. Information including socio-demographic characteristics, lifestyles, diet intake, and health status was collected by using questionnaires and physical examinations. Urine samples were collected to detect urinary cadmium and creatinine levels. Body circumferences included waist circumference, hip circumference and calf circumference. Subjects were divided into three groups (low:<0.77 μg/g·creatinine, middle:0.77-1.69 μg/g·creatinine, high:≥1.69 μg/g·creatinine) by tertiles of creatinine-adjusted urinary cadmium concentration. Multiple linear regression models were used to analyze the association of creatinine-adjusted urinary cadmium level with BMI and body circumferences. The dose-response relationship of creatinine-adjusted urinary cadmium concentration with BMI and body circumferences was analyzed by using restrictive cubic splines fitting multiple linear regression model. Results: The mean age of subjects was (83.34±11.14) years old. The median (Q1, Q3) concentration of creatinine-adjusted urinary cadmium was 1.13 (0.63, 2.09) μg/g·creatinine, and the BMI was (22.70±3.82) kg/m2. The mean values of waist circumference, hip circumference, and calf circumference were (85.42±10.68) cm, (92.67±8.90) cm, and (31.08±4.76) cm, respectively. After controlling confounding factors, the results of the multiple linear regression model showed that for each increment of 1 μg/g·creatinine in creatinine-adjusted urinary cadmium, the change of BMI, waist circumference, hip circumference, and calf circumference in the high-level group was -0.28 (-0.37, -0.19) kg/m2, -0.74 (-0.96, -0.52) cm, -0.78 (-0.96, -0.61) cm, and -0.20 (-0.30, -0.11) cm, respectively. The restrictive cubic splines curve showed a negative nonlinear association of creatinine-adjusted urinary cadmium with BMI (Pnonlinear<0.001) and negative linear associations of creatinine-adjusted urinary cadmium with waist circumference (Plinear<0.001), hip circumference (Plinear<0.001), and calf circumference (Plinear<0.001). Conclusion: Urinary cadmium level is significantly associated with decreased BMI, waist circumference, hip circumference and calf circumference among older adults over 65 years old in 9 longevity areas of China.

Association of hs-CRP with frailty and its components among the elderly over 65 years old in 9 longevity areas of China

Objective: To investigate the association of the levels of high sensitivity C-reactive protein (hs-CRP) with frailty and its components among the elderly over 65 years old in 9 longevity areas of China. Methods: Cross-sectional data from the Health Ageing and Biomarkers Cohort Study (HABCS, 2017-2018) were used and the elderly over 65 years old were included in this study. Through questionnaire interview and physical examination, the information including demographic characteristics, behavior, diet, daily activity, cognitive function, and health status was collected. The association between hs-CRP and frailty and its components in the participants was analyzed by multivariate logistic regression model and restrictive cubic spline. Results: A total of 2 453 participants were finally included, the age was (84.8±19.8) years old. The median hs-CRP level was 1.13 mg/L and the prevalence of frailty was 24.4%. Compared with the low-level group (hs-CRP<1.0 mg/L), the OR (95%CI) value of the high-level group (hs-CRP>3.0 mg/L) was 1.79 (1.35-2.36) mg/L. As for the components, the hs-CRP level was also positively associated with ADL disability, IADL disability, functional limitation and multimorbidity. After adjusting for confounding factors, compared with the low-level group, the OR (95%CI) values of the high-level group for the four components were 1.68 (1.25-2.27), 1.88 (1.42-2.50), 1.68 (1.31-2.14) and 1.39 (1.12-1.72), respectively. Conclusion: There is a positive association between the levels of hs-CRP and the risk of frailty among the elderly over 65 years old in 9 longevity areas of China. The higher hs-CRP level may increase the risk of frailty by elevating the risk of four physical functional disabilities, namely ADL disability, IADL disability, functional limitation and multimorbidity.

Association of plasma vitamin B12 level with plasma uric acid level among the elderly over 65 years old in 9 longevity areas of China

Objective: To investigate the association of plasma vitamin B12 level with plasma uric acid level among the elderly over 65 in 9 longevity areas of China. Methods: The elderly over 65 years old with complete information on plasma vitamin B12 and plasma uric acid from Healthy Aging and Biomarkers Cohort Study (2017 to 2018) were recruited in this study. Information on socio-demographic characteristics, life styles, diet intake, and health status were collected by questionnaire and physical examination; and fasting venous blood was collected to detect the levels of plasma vitamin B12, uric acid and other indicators. Multiple linear regression models were used to analyze the association of plasma vitamin B12 level per interquartile range increase with plasma uric acid level. The association trend of plasma vitamin B12 level with plasma uric acid level was described by restrictive cubic splines fitting multiple linear regression model. Multiple logistic regression models were used to analyze the association of plasma vitamin B12 level stratified by quartiles with hyperuricemia. Results: A total of 2 471 participants were finally included in the study, the age was (84.88±19.76) years old, of which 1 291 (52.25%) were female. The M (Q1, Q3) level of plasma vitamin B12 was 294 (203, 440) pg/ml and the plasma uric acid level was (341.01±90.46) μmol/L. A total of 422 participants (17.08%) were defined with hyperuricemia. The results of multiple linear regression model showed that there was a positive association of plasma vitamin B12 level with plasma uric acid level after adjustment for covariates (P<0.05). An IQR increase in plasma vitamin B12 (237 pg/ml) was associated with a 6.36 (95%CI: 2.00-10.72) μmol/L increase in the plasma uric acid level. The restrictive cubic splines curve showed a positive linear association of log-transformed plasma vitamin B12 with uric acid level (P<0.001). Conclusion: There is a positive association of plasma vitamin B12 level with plasma uric acid level among the elderly over 65 years old in 9 longevity areas of China.

Association of low cadmium and mercury exposure with chronic kidney disease among Chinese adults aged ≥80 years: A cross-sectional study.

The heavy metals cadmium (Cd) and mercury (Hg) are known to be widespread environmental contaminants and high occupational exposure adversely affects the risk of chronic kidney disease (CKD). However, evidence from epidemiological studies linking low Cd and Hg exposure (or non-industrial) to the risk of progression to CKD are conflicting. This study aimed to explore the association of low Cd and Hg exposure with the risk of CKD in Chinese adults aged ≥80 years. The participants were recruited for the Healthy Aging and Biomarkers Cohort Study in 2017, an ongoing perspective survey conducted in longevity areas in China initially involving 3016 older adults. We used logistic regression models to estimate odds ratios (ORs) with 95% confidence intervals of CKD setting Cd and Hg as categorical variables. Logistic regression with restricted cubic spline was used to characterize a dose-response relationships between Cd or Hg concentrations and the risk of CKD in the study population. The ORs for the risk of CKD comparing the fourth to the first quartile of blood Cd, blood Hg, urine Cd, and urine Hg were 1.77, 1.57, 2.03, and 1.50, respectively. Restricted cubic spline models showed that blood Cd and urine Hg were significantly linearly correlated with the risk of CKD, while blood Hg and urine Cd were non-linearly correlated with the risk of CKD with a steeper slope at concentrations <2.30 μg/L and 3.30 μg/g creatinine. Our findings suggest that even low Cd and Hg exposure (or non-industrial) were associated with increased risk of CKD in Chinese oldest old, although we did not find a significant multiplicative and additive interaction between Cd and Hg levels in relation to the risk of CKD.

Individualized prediction of chronic kidney disease for the elderly in longevity areas in China: Machine learning approaches.

Chronic kidney disease (CKD) has become a major public health problem worldwide and has caused a huge social and economic burden, especially in developing countries. No previous study has used machine learning (ML) methods combined with longitudinal data to predict the risk of CKD development in 2 years amongst the elderly in China. This study was based on the panel data of 925 elderly individuals in the 2012 baseline survey and 2014 follow-up survey of the Healthy Aging and Biomarkers Cohort Study (HABCS) database. Six ML models, logistic regression (LR), lasso regression, random forests (RF), gradient-boosted decision tree (GBDT), support vector machine (SVM), and deep neural network (DNN), were developed to predict the probability of CKD amongst the elderly in 2 years (the year of 2014). The decision curve analysis (DCA) provided a range of threshold probability of the outcome and the net benefit of each ML model. Amongst the 925 elderly in the HABCS 2014 survey, 289 (18.8%) had CKD. Compared with the other models, LR, lasso regression, RF, GBDT, and DNN had no statistical significance of the area under the receiver operating curve (AUC) value (>0.7), and SVM exhibited the lowest predictive performance (AUC = 0.633, p-value = 0.057). DNN had the highest positive predictive value (PPV) (0.328), whereas LR had the lowest (0.287). DCA results indicated that within the threshold ranges of ~0-0.03 and 0.37-0.40, the net benefit of GBDT was the largest. Within the threshold ranges of ~0.03-0.10 and 0.26-0.30, the net benefit of RF was the largest. Age was the most important predictor variable in the RF and GBDT models. Blood urea nitrogen, serum albumin, uric acid, body mass index (BMI), marital status, activities of daily living (ADL)/instrumental activities of daily living (IADL) and gender were crucial in predicting CKD in the elderly. The ML model could successfully capture the linear and nonlinear relationships of risk factors for CKD in the elderly. The decision support system based on the predictive model in this research can help medical staff detect and intervene in the health of the elderly early.

Association between urinary arsenic levels and anemia among older adults in nine longevity areas of China

Objective: To investigate the association between urinary arsenic levels and anemia among older adults in nine longevity areas of China. Methods: A total of 1 896 subjects aged 65 years and above who participated in the Healthy Aging and Biomarkers Cohort Study (HABCS) in 2017-2018 were included. A self-made questionnaire was used to collect demographic characteristics, lifestyle and other information from the subjects. Through physical examination, data including height, weight and blood pressure were determined and body mass index (BMI) was calculated. Blood and urine samples were collected for the detection of hemoglobin (Hb), blood glucose, blood lipids, plasma vitamin B12 and urinary arsenic concentrations. The urinary arsenic levels were divided into four groups according to the quartiles of urinary arsenic concentrations (μg/g creatinine): Q1 (<18.7), Q2 (18.7-34.5), Q3 (34.6-69.5) and Q4(≥69.6). Multivariate logistic regression model and restricted cubic spline fitting logistic regression model were used to analyze the association between urinary arsenic levels and anemia. Results: The age of the 1 896 subjects (M (Q1, Q3)) was 83 (74, 92) years, including 952 females (50.21%), and the concentration of Hb (M (Q1, Q3)) was 135 (124, 147)g/L. The prevalence of anemia was 24.89% (472 cases). The geometric mean and M (Q1, Q3) of urinary arsenic concentrations were 37.5 and 34.6 (18.7, 69.6)μg/g creatinine, respectively. Multivariate logistic regression model analysis showed that after adjusting for age, gender, BMI, education level, smoking and drinking status, residence, economic level, ethnicity, the status of vitamin B12 deficiency, consumption frequency of aquatic products and meat, the prevalence of hypertension, diabetes and dyslipidemia, urinary arsenic levels were positively associated with anemia (Taking group Q1 as a reference, OR (95%CI) values in Q2, Q3 and Q4 groups were 1.73 (1.20-2.50), 2.08 (1.43-3.02) and 1.52 (1.02-2.28), respectively). The results of restricted cubic spline fitting logistic regression analysis showed a non-linear association between urinary arsenic concentrations and anemia (P<0.001). Subgroup analysis showed there was a negative multiplicative interaction between the prevalence of chronic diseases and urinary arsenic levels with OR (95%CI) was 0.55 (0.30-0.99), while no multiplicative interaction was found between age, gender, residence, smoking status, drinking status and urinary arsenic levels (P>0.05). There was a positive association between urinary arsenic levels and anemia in participants who were absence of chronic diseases,male, living in rural, smoking and drinking with OR (95%CI) values of 3.62 (1.30-10.06),2.46 (1.34-4.52), 1.70 (1.03-2.80), 2.21 (1.01-4.82) and 2.79 (1.23-6.33), respectively. Conclusion: There is a positive association between urinary arsenic levels and anemia among older adults in nine longevity areas of China.

A cohort study on plasma uric acid levels and the risk of type 2 diabetes mellitus among the oldest old in longevity areas of China

Objective: To investigate the effect of plasma uric acid level on the incident risk of type 2 diabetes mellitus (T2DM) among the oldest old (those aged ≥80 years). Methods: Participants were recruited from the Healthy Aging and Biomarkers Cohort Study (HABCS), which conducted a baseline survey in 2008-2009 and follow-up of 3 times in 2011-2012, 2014, and 2017-2018, respectively. A total of 2 213 oldest old were enrolled in this study. The general demographic, socioeconomic, lifestyle and disease data of the oldest old were collected, and physical measurements were made for the oldest old. Fasting venous blood was collected for uric acid and blood glucose detection. Information on the incident and death of T2DM were collected through the follow-up. Cox proportional hazard regression model was used to explore the association of hyperuricemia and plasma uric acid level with the incidence of T2DM. Restricted cubic spline (RCS) function was used to explore the dose-response relationship of plasma uric acid levels with the risk of T2DM. Results: The age of participants was (93.2±7.6) years old, and 66.7% of the participants (1 475) were female. The plasma uric acid level at baseline was (289.1±88.0)μmol/L, and the prevalence of hyperuricemia was 13.3% (294 cases). During 9 years of cumulative follow-up of 7 471 person-years (average of 3.38 years for each), 122 new cases of T2DM occurred and the incidence density was 1 632.98/105 person year. Cox proportional hazards regression analysis showed that per 10μmol/L increase in plasma uric acid level, the risk of T2DM increased by 1.1% [HR (95%CI): 1.011 (1.004, 1.017)]. Compared with the participants with the lowest quintile of plasma uric acid (Q1), the risk of diabetes increased by 20.7 % among the oldest old with uric acid in the highest quintile (Q5) [HR (95%CI):1.207 (1.029, 1.416)]. The risk of T2DM was 19.2% higher in the hyperuricemia group than that in the oldest old with normal plasma uric acid [HR (95%CI): 1.192 (1.033, 1.377)]. RCS function showed that the risk of T2DM increased with the increase in plasma uric acid levels in a nonlinear dose-response relationship (P=0.016). Conclusion: The incident risk of T2DM increases with the elevates of plasma uric acid levels in the oldest old.

Association of neutrophil-to-lymphocyte ratio with depressive symptoms among older adults aged 65 years and above in 9 longevity areas of China

Objective: To investigate the relationship between the neutrophil-to-lymphocyte ratio (NLR) and the risk of depression symptoms among older adults aged 65 and above in 9 longevity areas of China. Methods: Data was collected in 9 longevity areas of China from Healthy Aging and Biomarkers Cohort Study (HABCS) conducted between 2017 and 2018. Finally,2018 elderly aged 65 years and above with complete information on neutrophil count, lymphocyte count and depressive symptoms were included in this study. Information on demographic characteristics, lifestyle, and health status was collected through questionnaire and physical examination. Complete blood counts which included lymphocytes and neutrophils were obtained by testing venous blood samples. Participants were divided into four groups by the quartile of NLR level, i.e. Q1, Q2, Q3, Q4. Logistic regression model was applied to analyze the association of NLR with depression symptoms. Results: Among 2 018 older adults, the mean(±SD) age was 82.6(±10.73), 1 032(51.14%) were male, 390(19.33%) were detected with depressive symptoms. Compared with participants of NLR in the 1st quartile, the OR(95%CI) of risk for depressive symptoms was 1.47 (0.99, 2.19), 1.67 (1.13, 2.47) and 1.95 (1.32, 2.89), respectively. Conclusion: Increased NLR level is significantly related to depressive symptoms among elderly aged 65 years and above in 9 longevity areas in China.

Association of blood uric acid and cognitive impairment in oldest-old aged 80 years and older in 9 longevity areas of China

Objective: To examine the association of blood uric acid (UA) and cognitive impairment (CI) among oldest-old adults in China. Methods: Data was collected in 9 longevity areas of China from Healthy Aging and Biomarkers Cohort Study (HABCS) conducted during 2017-2018. Finally,1, 622 elderly aged 80 years and older with complete information on blood UA and cognitive function score were included in this study. Information on demographic characteristics, lifestyle, and health status were collected through questionnaire and physical examination. Venous blood samples of the participants were collected to test blood UA level. Cognitive impairment (CI) was assessed using the Chinese Mini-Mental State Examination (MMSE) according to personal educational level. Generalized Estimating Equations (GEE) model for binary data was used to analyze the association of blood UA and CI, and further compared the associations among different age and body mass index (BMI) groups. Results: Of the 1 622 oldest-old, the mean age was (92.2±8.1) years, 656 (40.4%) were male, the mean level of blood UA was (343.3±86.2) μmol/L, and 482 (29.7%) oldest-old had CI. Compared with the lowest quartile of UA, the risks of CI in the second, third and highest quartiles were gradually reduced, the corresponding ORs and 95%CI were 0.99 (0.71-1.33), 0.87 (0.68-0.94) and 0.69 (0.48-0.85), respectively; and the linear trend test was statistically significant (P<0.001). Subgroup analysis showed that the effects of higher UA associated with lower risk of CI were stronger in younger oldest-old (aged 80-89 years) and thinner group (BMI<24) (Pinteraction<0.05). Conclusions: Blood UA was negatively associated with the risk of having CI in the oldest-old among the nine longevity areas of China.

Association of blood oxidative stress level with hypertriglyceridemia in the elderly aged 65 years and older in 9 longevity areas of China

Objective: To investigate the association of blood oxidative stress level with hypertriglyceridemia in the elderly aged 65 years and older in China. Methods: A total of 2 393 participants aged 65 years and older were recruited in 9 longevity areas from Heathy Aging and Biomarkers Cohort Study, during 2017 to 2018. Information on demographics characteristic, life style and health status were collected by questionnaire and physical examination, and venous blood was collected to detect the levels of blood oxidative stress and hypertriglyceridemia. The linear or non-linear association between oxidative stress and hypertriglyceridemia was described by restrictive cubic splines (RCS) fitting multiple linear regression model. The generalized linear mixed effect model was conducted to assess the association between oxidative stress and hypertriglyceridemia. Results: A total of 2 393 participants, mean age was 84.6 years, the youngest was 65 and the oldest was 112, the male was 47.9%(1 145/2 393), the triglyceride level was (1.4±0.8) mmol/L. The hypertriglyceridemia detection rate was 9.99%(239/2 393). The results of multiple linear regression model with restrictive cubic spline fitting showed that MDA level was linear association with triglyceride level; SOD level was nonlinear association with triglyceride level. MDA level had significantly association with hypertriglyceridemia, and the corresponding OR value was 1.063 (95%CI: 1.046,1.081) with 1 nmol/ml increment of blood MDA; SOD level had significantly association with hypertriglyceridemia, and the corresponding OR value was 0.986(95%CI: 0.983,0.989) with 1 U/ml increment of blood SOD. Conclusion: Among the elderly aged 65 and older in 9 longevity areas in China, MDA and SOD levels were associated with the risk of hypertriglyceridemia.

Effects of oxygen saturation on all-cause mortality among the elderly over 65 years old in 9 longevity areas of China

Objective: To investigate the association between oxygen saturation (SpO2) and risk of 3-year all-cause mortality among Chinese older adults aged 65 or over. Methods: The participants were enrolled from Healthy Aging and Biomarkers Cohort Study in year of 2012 to 2014 in 9 longevity areas in China. In this prospective cohort study, 2 287 participants aged 65 or over were enrolled. Data on SpO2 and body measurements were collected at baseline in 2012, and data on survival outcome and time of mortality were collected at the follow-up in 2014. Participants were divided into two groups according to whether SpO2 was abnormal (SpO2<94% was defined as abnormal). Results: The 2 287 participants were (86.5±12.2) years old, 1 006 were males (44.0%), and 315 (13.8%) were abnormal in SpO2. During follow-up in 2014, 452 were died, 1 434 were survived, and 401 were lost to follow-up. The all-cause mortality rate was 19.8%, and the follow-up rate was 82.5%. The mortality rate of SpO2 in normal group was 21.1%, and that of abnormal group was 41.6% (P<0.001). After adjusting for confounding factors, compared to participants with normal SpO2, participants with abnormal SpO2 had increased risk of all-cause mortality with HR (95%CI) of 1.62 (1.31-2.02); HR (95 % CI) was 1.49 (0.98-2.26) for males and 1.71 (1.30-2.26) for females in abnormal SpO2 group, respectively; HR (95%CI) was 2.70 (0.98-7.44) for aged 65-79 years old, 1.22 (0.63-2.38) for aged 80-89 years old, and 1.72 (1.35-2.19) for aged over 90 years old in abnormal SpO2 group, respectively. Conclusion: Abnormal SpO2 was responsible for increased risk of 3-year all-cause mortality among Chinese elderly adults.

Association of blood lead level with cognition impairment among elderly aged 65 years and older in 9 longevity areas of China

Objective: To investigate the association between blood lead concentrations and cognition impairment among Chinese older adults aged 65 or over. Method: Data was collected in 9 longevity areas from Heathy Aging and Biomarkers Cohort Study between 2017 and 2018. This study included 1 684 elderly aged 65 years and older. Information about demographic characteristics, socioeconomic factors, health status and cognitive function score of respondents were collected by questionnaire survey and physical examination. Venous blood of the subjects was collected to detect the blood lead concentration. Subjects were stratified into four groups (Q1-Q4) by quartile of blood lead concentration. Multivariate logistic regression model was used to analyze the association between blood lead concentration and cognitive impairment. The linear or non-linear association between blood lead concentration and cognitive impairment were described by restrictive cubic splines (RCS). Results: Among the 1 684 respondents, 843 (50.1%) were female and 191 (11.3%) suffered from cognition impairment. After adjusting for confounding factors, the OR value and 95%CI of cognition impairment was 1.05 (1.01-1.10) for every 10 μg/L increase in blood lead concentration in elderly; Compared with the elderly in Q1, the elderly with higher blood lead concentration had an increased risk of cognitive impairment. The OR value and 95%CI of Q2, Q3 and Q4 groups were 1.19 (0.69-2.05), 1.45 (0.84-2.51) and 1.92 (1.13-3.27), respectively. Conclusion: Higher blood lead concentration is associated with cognitive impairment among the elderly aged 65 years and older in 9 longevity areas in China.

Association of blood arsenic level with hyperuricemia among elderly aged 65 years and older in 9 longevity areas of China

Objective: To investigate the association of blood arsenic level with hyperuricemia among elderly aged 65 years and older. Methods: Data was collected in 9 longevity areas from Heathy Aging and Biomarkers Cohort Study between 2017 and 2018. 2 438 participants aged 65 years and older with complete information on blood arsenic and uric acid were included in this study. Information including demographics characteristic, life style and health status was collected by questionnaire and physical examination. Meanwhile, venous blood was collected to detect the levels of blood arsenic and uric acid. Subjects were stratified into three groups (low, middle and high) by tertiles of blood arsenic level. Logistic regression models were used to analyze the association of blood arsenic level with hyperuricemia. Results: The age of participants was (84.57±11.41) years, of which 1 172 (48.07%) were male and 1 525 (62.55%) were over 80 years old. The detection rate of hyperuricemia was 17.23% (420), and the detection rates of hyperuricemia were 11.77%, 19.25% and 20.62% among participants with low, middle and high blood arsenic, respectively (P<0.001). After controlling confounding factors, compared with participants who had low blood arsenic, the ORs (95%CI) of hyperuricemia for the participants with middle and high blood arsenic were 1.57 (1.12-2.23) and 2.08 (1.46-2.99), respectively. Subgroups analysis showed that compared with female, the association between blood arsenic level and hyperuricemia was more obvious in males (Pinteraction<0.05). Conclusion: Blood arsenic level is associated with the risk for hyperuricemia among the elderly aged 65 years and older in 9 longevity areas in China.

Plasma element levels and risk of chronic kidney disease in elderly populations (≥ 90 Years old)

Associations between plasma elements and chronic kidney disease (CKD) among the elderly are poorly understood. In this cross-sectional study, we explored the associations between exposure to four plasma elements and CKD in elderly people aged ≥90 years in longevity areas in China. We measured plasma selenium, manganese, iron, and zinc levels and used logistic regression models to investigate associations between CKD and these four plasma elements after adjusting for confounding factors among 461 participants aged ≥90 years in the fifth wave of the Chinese Longitudinal Healthy Longevity Study (CLHLS) conducted in 2009. The median plasma selenium, manganese, iron, and zinc levels were 120.51 μg/L, 26.64 μg/L, 2880.52 μg/L, and 1882.42 μg/L in the CKD group and 108.76 μg/L, 31.55 μg/L, 4512.00 μg/L, and 2294.24 μg/L in the non-CKD group, respectively. Single- and multiple-element multivariable models showed that plasma manganese, iron, and zinc were negatively associated with CKD. In the multiple-element multivariable models, the adjusted odds ratios for CKD were 0.48 (95% confidence interval [CI]: 0.27–0.86) for the second highest quartile of manganese, 0.37 (95% CI: 0.21–0.68) and 0.36 (95% CI: 0.19–0.65) for the third highest and highest quartiles of iron, respectively, and 0.53 (95% CI: 0.29–0.94) for the highest quartile of zinc, compared with the lowest quartiles of these three elements. Plasma manganese, iron, and zinc levels protect against CKD in elderly people aged ≥90 years in longevity areas.

Current status of body mass index and related influencing factors in the elderly aged 65 years and older in 8 longevity areas in China

Objective: To understand the current status of BMI of the elderly and related factors in longevity areas in China, and provide scientific evidence for the control of BMI level in elderly population. Methods: Data used in this study were obtained from Healthy Aging and Biomarkers Cohort Study, a sub-cohort of the Chinese Longitudinal Healthy Longevity Survey. A total of 2 825 elderly in 8 longevity areas in China were surveyed and measured in 2017. The BMI levels of 2 217 elderly aged 65 years and older were calculated and in follow up. The ordered classification logistic regression model was used to analyze the influencd factors for the BMI in the elderly. Results: The BMI of the elderly in 8 longevity areas in China was (22.36±3.87) kg/m(2), and it was (22.76±3.58) kg/m(2) for males and (21.75±3.98) kg/m(2) for females. The BMI levels were normal in 1 165 elderly persons. The prevalence of underweight, overweight and obesity were 15.8%, 24.0% and 7.7%, respectively. Multivariate analysis showed that the main factors affecting the BMI of people under 100- years old were age (65-: OR=2.78, 95%CI: 1.87-4.15; 80-: OR=1.47, 95%CI: 1.00-2.17), smoking status (OR=0.46, 95%CI: 0.32-0.66), annual household income (<30 000 Yuan: OR=1.26, 95%CI: 1.07-1.47; 30 000-70 000 Yuan: OR=1.52, 95%CI: 1.12-1.86), and frequency of tea intake(OR=1.36, 95%CI: 1.01-1.71), while the factor in people aged ≥100 years was gender (OR=3.68, 95%CI: 1.32-10.36). Conclusions: The prevalence of underweight, overweight and obesity were high in the elderly from longevity areas in China. It is necessary to pay attention to the trend of overweight and obesity due to smoking, higher annual household income and regular tea drinking in the elderly men.

Effects of estimated glomerular filtration rate on all-cause mortality in the elderly aged 65 years and older in 8 longevity areas in China

Objective: To investigate the association between estimated glomerular filtration rate (eGFR) and all-cause mortality in the elderly aged 65 years and older in longevity areas in China. Methods: Data used in this study were obtained from Healthy Aging and Biomarkers Cohort Study, a sub-cohort of the Chinese Longitudinal Healthy Longevity Survey, 1 802 elderly adults were collected in the study during 2012-2017/2018. In this study, the elderly were classified into 4 groups, moderate-to-severe group [<45 ml·min(-1)·(1.73 m(2))(-1)], mild-to-moderate group [45- ml·min(-1)·(1.73 m(2))(-1)], mild group [60- ml·min(-1)·(1.73 m(2))(-1)] and normal group [≥90 ml·min(-1)·(1.73 m(2))(-1)] according to their eGFR levels. Results: After 6 years of follow-up, 852 participants died, with a mortality rate of 47.3%. Multivariate Cox regression analysis showed that the levels of eGFR were negatively correlated with all-cause mortality risk in the elderly (the HR of elderly was 0.993 and the 95%CI was 0.989-0.997 for every unit of eGFR increased, P=0.001), while compared with the group with normal eGFR, the HRs (95%CI) of the elderly in the moderate-to-severe group, mild-to-moderate group, and mild group were 1.690 (1.224-2.332, P=0.001), 1.312 (0.978-1.758, P=0.070), 1.349 (1.047-1.737, P=0.020) respectively [trend test P<0.001]. Conclusion: The decrease in eGFR was associated with higher mortality risk among the elderly in longevity areas in China.

Influencing factors for depressive symptoms in the elderly aged 65 years and older in 8 longevity areas in China

Objective: To analyze influencing factors for depressive symptoms in the elderly aged 65 years and older in 8 longevity areas in China. Methods: We recruited 2 180 participants aged 65 years and older in 8 longevity areas from Healthy Aging and Biomarkers Cohort Study, a sub-cohort of the Chinese Longitudinal Healthy Longevity Survey in 2017. Multivariate logistic regression analysis was performed to evaluate the relationships of socio-demographic characteristics, behavioral lifestyle, chronic disease prevalence, functional status, family and social support with depressive symptoms in the elderly. Results: The detection rate of depression symptoms was 15.0% in the elderly aged 65 years and older in 8 longevity areas of China, and the detection rate of depression symptoms was 11.5% in men and 18.5% in women. Multivariate logistic regression analysis results showed that the detection rate of depressive symptoms was lower in the elderly who had regular physical exercises (OR=0.44, 95%CI: 0.26-0.74), frequent fish intakes (OR=0.57, 95%CI: 0.39-0.83), recreational activities (OR=0.65, 95%CI: 0.44-0.96), social activities (OR=0.28, 95%CI: 0.11-0.73) and community services (OR=0.68, 95%CI: 0.50-0.93). The elderly who were lack of sleep (OR=2.04, 95%CI: 1.49-2.80), had visual impairment (OR=1.54, 95%CI: 1.08-2.18), had gastrointestinal ulcer (OR=2.97, 95%CI: 1.53-5.77), had arthritis (OR=2.63, 95%CI: 1.61-4.32), had higher family expenditure than income (OR=1.80, 95%CI: 1.17-2.78) and were in poor economic condition (OR=4.58, 95%CI: 2.48-8.47) had higher detection rate of depressive symptoms. Conclusion: The status of doing physical exercise, fish intake in diet, social activity participation, sleep quality or vision, and the prevalence of gastrointestinal ulcers and arthritis were associated with the detection rate of depressive symptoms in the elderly.

Influence of visual impairment on mortality in the elderly aged 65 years and older in 8 longevity areas in China

Objective: To understand the relationship between visual impairment and risk of all-cause mortality in the elderly aged 65 years and older in 8 longevity areas in China. Methods: The data of the elderly aged 65 years and older in the project in 2012 were obtained from Healthy Aging and Biomarkers Cohort Study, a sub-cohort of the Chinese Longitudinal Healthy Longevity Survey, including physical measurement and survival status, and a follow-up for survival outcomes were conducted in 2014 and 2017 respectively. Cox proportional hazard regression model was used to analyze the influence of visual impairment on mortality. Gender and age specific analysis was conducted. Results: A total of 1 736 elderly adults were included. A total of 943 deaths occurred during the 5-year follow-up period with a 5-year mortality rate of 54.3%. The 5-year mortality rate was 76.7% in the group with visual impairment, and 47.6% in the group without visual impairment (P<0.001). After adjusting for demographic information, life style and some disease factors, the risk of 5-year mortality in the group with visual impairment group was 1.30 times higher than that in the group without visual impairment (HR=1.30, 95%CI: 1.09-1.55). In the females, the risk for mortality in the group with visual impairment was 1.48 times higher than that in the group without visual impairment (HR=1.48, 95%CI:1.20-1.84). However, vision status was not associated with the risk for mortality in males (HR=1.02, 95%CI: 0.72-1.43). The risk for mortality in the group with visual impairment was 1.39 times higher than that in the group without visual impairment in the elderly aged over 90 years (HR=1.39, 95%CI: 1.13-1.70). Vision status was not associated with mortality risk in the elderly aged 65-79 years and 80-89 years (HR=1.37, 95%CI: 0.61-3.07; HR=0.95, 95%CI: 0.61-1.48). Conclusion: In the elderly people in China, visual impairment is a risk factor for mortality.

Prediction of 6-year incidence risk of chronic kidney disease in the elderly aged 65 years and older in 8 longevity areas in China

Objective: To establish a prediction model for 6-year incidence risk of chronic kidney disease (CKD) in the elderly aged 65 years and older in China. Methods: In this prospective cohort study, we used the data of 3 742 participants collected during 2008/2009-2014 and during 2012-2017/2018 from Healthy Aging and Biomarkers Cohort Study, a sub-cohort of the Chinese Longitudinal Healthy Longevity Survey. Two follow up surveys for renal function were successfully conducted for 1 055 participants without CKD in baseline survey. Lasso method was used for the selection of risk factors. The risk prediction model of CKD was established by using Cox proportional hazards regression models and visualized through nomogram tool. Bootstrap method (1 000 resample) was used for internal validation, and the performance of the model was assessed by C-index and calibration curve. Results: The mean age of participants was (80.8±11.4) years. In 4 797 person years of follow up, CKD was found in 262 participants (24.8%). Age, BMI, sex, education level, marital status, having retirement pension or insurance, hypertension prevalence, blood uric acid, blood urea nitrogen and total cholesterol levels and estimated glomerular filtration rate in baseline survey were used in the model to predict the 6-year incidence risk of CKD in the elderly. The corrected C-index was 0.766, the calibration curve showed good consistence between predicted probability and observed probability in high risk group, but relatively poor consistence in low risk group. Conclusion: The incidence risk prediction model of CKD established in this study has a good performance, and the nomogram can be used as visualization tool to predict the 6-year risk of CKD in the elderly aged 65 years and older in China.

Healthy Ageing and Biomarkers Cohort Study (HABCS): a cohort profile

PurposeThe Chinese Longitudinal Healthy Longevity Survey Biomarkers Cohort (Healthy Ageing and Biomarkers Cohort Study (HABCS)) was established to investigate the determinants of healthy aging and mortality among the oldest old...