[Association between oxygen saturation and cognitive function in older adults from longevity areas in China]

OBJECTIVE

To explore the relationship between oxygen saturation (SpO2) and cognitive function in older adults from longevity areas in China.

METHODS

A total of 2 285 participants aged ≥65 years according to the 2012 Chinese Longitudinal Healthy Longevity Survey were included in this study. Among them, 1 739 participants aged 65-99 years were randomly selected, and 546 participants aged ≥100 years were totally involved. A standardized questionaire was used to collect the information of demographic characteristics, life styles, disease history, etc. Cognitive function was evaluated using the Mini Mental State Examination Scale. Arterial oxygen saturation and heart rate were measured by pulse oximetry. Differences in cognitive function between the low SpO2 group (<0.94) and normal SpO2 group (≥0.94) were analyzed, and logistic regression models were used to analyze the relationship between SpO2 and cognitive function.

RESULTS

The total score of cognitive function was 22.6±9.7 for the 1 922 participants in the normal SpO2 group, and 18.8 ± 11.0 for the 363 participants in the low SpO2 group (t=6.11, P<0.001). The proportion of cognitive impairment in the low SpO2 group was 36.6% (n=133), and 22.9% (n=441) in the normal SpO2 group (χ(2)=30.44, P<0.001). RESULTS from stepwise logistic regression analysis showed that the risk of cognitive impairment increased with each year of increased age (OR 1.07; (95% CI: 1.05-1.09), P<0.001). Low SpO2, vision disorders, impaired activities of daily living, dyslipidemia, unmarried status, and lack of exercise were also associated with increased risk of cognitive impairment (OR 1.64; (95% CI: 1.11-2.43), OR 1.73; (95% CI: 1.27-2.35), OR 3.54; (95% CI: 2.62-4.79), OR 1.38; (95% CI: 1.02-1.86), OR 2.05; (95% CI: 1.34-3.13), OR 1.83; (95% CI: 1.13-2.97), respectively, P<0.05). Stratified analysis by age group showed that the association between SpO2 and cognitive impairment was most significant in participants aged ≥90 years (OR 1.58; (95% CI: 1.09-2.28), P=0.016).

CONCLUSION

Low oxygen saturation was associated with higher risk of cognitive impairment in our population of elderly adults.

[Current situation, problems and suggestions of environmental health standardization]

In this paper, the history and current situation of environmental health standardization in China are reviewed, and the experience and shortcomings in the process of environmental health standardization in China are analyzed, suggestions for the next step of environmental health standards are also put forward.

[Determination of samarium oxide and lanthanum oxide in the air of workplace by inductively coupled plasmamass spectrometry]

Objective: To establish a method for the determination ofsamarium oxide and lanthanum oxide by inductively coupled plasmamass spectrometryin the air of workplace. Methods: Samarium, lanthanum and their compounds in the air of workplace were collected through microporous filter. The samples were digested by nitricacid and perhydrol (V/V=4∶1) and detected by inductively coupled plasmamass spectrometry. Results: The linear range ofsamarium oxide and lanthanum oxide was 0-50.00 μg/L, Sm(2)O(3): y=0.0119x, r=0.9999; La(2)O(3): y=0.0617x, r=0.9998. The detection limits were less than 0.1 μg/L, and the minimum detection concentration were less than 1.52×10(-5) mg/m(3). The sampling efficiency were 100%, the recovery rates were 95.70%-102.01%, and the precision were 0.78%-1.58%. Conclusion: The indicators established in this study are conformed with the requirements of Chinese Occupational Standars of GBZ/T 210.4-2008, "The Guidelines for the Development of Occupational Hygiene StandarsMehods Part 4: Determination of Chemical Substances in the Air of Workplace".

[Association between biomarkers and activities of daily living in the elderly ≥65 years old from longevity areas in China]

Objective: To explore the association between biomarkers and activities of daily living (ADL) in the elderly over 65 years old from longevity areas in China. Methods: A total of 2 439 people from 8 longevity areas were included in our baseline survey in 2012. Using questionnaires, body measurements, and blood biochemical examinations, information on demographics characteristic, life style, ADL, blood pressure and biomarkers were collected. Based on these six items of ADL (bathing, dressing, indoor activities, toileting, eating, bowel and bladder control), we constructed a dichotomous indicator for ADL. A respondent was defined as ADL disabled if any difficulty in one or more of the above six activities was reported. Information were collected in the follow-up in 2014 using the same questionnaires and examinations. We excluded information on the elderly who lacked ADL or biomarkers test results or with ADL disability at baseline study. Finally 938 elderly people over 65 years old were included in this analysis. Multivariate logistic regression model was used to analyze the influence factors of ADL disability. Results: During the 2-year follow-up, 100 (10.7%) participants developed into ADL disability, with a rate at 10.7%. Multivariate logistic regression analysis indicated that each year increase in age or each 1 mmHg (1 mmHg=0.133 kPa) increase in systolic blood pressure (SBP) would cause the risk of ADL disability to increase 9% or 1%, whose OR (95%CI) were separately 1.09 (1.06-1.12), 1.01 (1.00-1.02). Han nationality or cognitive impairment increased the risk of ADL disability, whose OR (95%CI) values were separately 4.90 (1.13-21.24), 2.47 (1.44-4.25), while increased lymphocyte count (>1.60×10(9)/L), being married, or participating in recreational activities decreased the risk of ADL disability, whose OR (95%CI) values were separately 0.51 (0.31-0.82), 0.52 (0.28-0.96), 0.43 (0.23-0.80). Conclusion: In the elderly elevated lymphocyte count was associated with lower risk of ADL disability. In addition, incresed age, increased SBP, unmarried, Han nationality or cognitive impairment were associated with the increasing risk of ADL disability in older people, while participating in recreational activities would reduce the risk.

[A review on the research progress related to ambient air pollution and depression]

It is reported that depression has caused heavy disease burden across the world, with an possible association between ambient air pollution and depressive symptoms. In this paper, we reviewed relative literature in this field and summarized the research events on association between ambient air pollution and depression, both in China and abroad and found that the results of the existed studies were inconsistent, with most studies showing that there existed a positive correlation between the exposure of air pollution and depression, but few studies showing the negative correlation or no correlation between the two.

[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 lifestyle and apolipoprotein E gene with risk for cognitive frailty in elderly population in China]

Objective: To investigate the impact of lifestyle, apolipoprotein E (ApoE) gene, and their interaction on the risk for cognitive frailty in the elderly population in China. Methods: The study participants were from the Chinese Longitudinal Healthy Longevity Survey. The information about their lifestyles were collected by questionnaire survey, and a weighted lifestyle score was constructed based on β coefficients associated with specific lifestyles to assess the combined lifestyle. ApoE genotypes were assessed by rs429358 and rs7412 single nucleotide polymorphisms. Cognitive frailty was assessed based on cognitive function and physical frailty. Cox proportional hazards regression model was used to analyze the association of lifestyle and ApoE gene with the risk for cognitive frailty and evaluate the multiplicative and additive interactions between lifestyle and ApoE gene. Results: A total of 5 676 elderly persons, with median age [M (Q1, Q3)] of 76 (68, 85) years, were included, in whom 615 had cognitive frailty. The analysis by Cox proportional hazards regression model indicated that moderate and high levels of dietary diversity could reduce the risk for cognitive frailty by 18% [hazard ratio (HR)=0.82, 95%CI: 0.68-1.00] and 28% (HR=0.72, 95%CI: 0.57-0.91), respectively; moderate and high levels of physical activity could reduce the risk by 31% (HR=0.69, 95%CI: 0.56-0.85) and 23% (HR=0.77, 95%CI: 0.64-0.93), respectively. Healthy lifestyle was associated with a 40% reduced risk for cognitive frailty (HR=0.60, 95%CI: 0.46-0.78). ApoE ε4 allele was associated with a 26% increased risk for cognitive frailty (HR=1.26, 95%CI: 1.02-1.56). No multiplicative or additive interactions were found between lifestyle and ApoE gene. Conclusions: Dietary diversity and regular physical activity have protective effects against cognitive frailty in elderly population. Healthy lifestyle can reduce the risk for cognitive frailty in elderly population regardless of ApoE ε4 allele carriage status.

[The relationship between resting heart rate and all-cause mortality among the Chinese oldest-old aged more than 80: a prospective cohort study]

Objective: To explore the association between resting heart rate(RHR) and all-cause mortality among the Chinese oldest-old aged more than 80. Methods: Using a total of seven surveys or follow-ups data (1998, 2000, 2002, 2005, 2008, 2011 and 2014) from the Chinese Longitudinal Healthy Longevity Survey (CLHLS). A total of 17 886 elderly over 80 years old were selected as subjects, their resting heart rate were measured though baseline survey and the survival outcome and death time of the subjects were followed up. The subjects were divided into 6 groups according to their resting heart rate. Cox regression model was used to estimate the effect of resting heart rate on mortality risk. The interaction of age, gender and resting heart rate was also analyzed by likelihood ratio test. Results: The age of subjects M (P₂₅, P₇₅) was 92 (86, 100) years old, including 10 531 females (58.9%) and there were 13 598 participants died, the mortality rate was 195.5 per 1 000 person-years. Multivariate Cox regression analysis showed that compared to the control group (60-69 pbm/min), the hazard ratio of the elderly are 1.06 (95%CI: 1.02, 1.11), 1.09 (95%CI: 1.04, 1.15), 1.23 (95%CI: 1.14, 1.34), 1.25 (95%CI: 1.08, 1.44) in the group of RHR between 70-79, 80-89, 90-99 and ≥100 pbm/min and P values are all less than 0.05. Likelihood ratio test showed that RHR and age had an interaction effect. (P for interaction=0.011). Conclusion: The risk of all-cause death increased with the increase of resting heart rate and this relationship was stronger between the 80-89 years old people.

[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.

Relationships between biochemical and physiological changes induced by exercise in postmyocardial infarction patients

AIM

AIM of the study was to examine the relationships between biochemical and physiological changes induced by exercise in postmyocardial infarction patients (PMIP) during the early stages of cardiac rehabilitation.

METHODS

Forty-nine male non-blockade recent PMIP, aged 63.8 ± 4.7 years, performed a graded exercise test on a motorised treadmill until volitional cessation or reaching any of the American College of Sports Medicine criteria. Blood pressure and rate-pressure product (RPP) were recorded every three minutes. A 12-lead electrocardiogram was monitored continuously and heart rate (HR) was taken from this. Blood samples were obtained by two methods; those used for testing blood lactate (BL) were taken from an already warmed finger tip before and during exercise, and the others used for enzymatic analysis based on lactate dehydrogenase (LDH), lactate dehydrogenase isoenzyme 1 (LDH-1), creatine kinase (CK) and creatine kinase polypeptide sub-unit MB (CK-MB) were collected by venipuncture from the antecubital vein pre and immediate post exercise test.

RESULTS

Highly significant correlations existed between exercise-induced changes in HR, RPP, BL and ST segment level with increased enzymes activity in serum, and 73.1% to 90.1% of the variance in percentage increase of the enzyme activity could be predicted from the variance in percentage increase of HR during exercise. However, the mechanism of these relationships may differ.

CONCLUSION

Since the rise in serum enzymes during submaximal exercise is primarily attributed to changes in membrane permeability in fatigued muscle, these relationships provide useful guidance to health professionals obtaining biochemical information about muscle fatigue.

[Simulation study of air quality health index in 5 cities in China: 2013-2015]

Objective: To construct the air quality health index (AQHI) by inclusion of air pollutants PM(2.5) and O(3) in Guangzhou, Shanghai, Xi' an, Beijing, Shenyang, and explore scientificity and feasibility of its application in China. Methods: The daily average concentrations of PM(2.5) and O(3) in air, and daily average mortality from 2013 to 2015 in the 5 cities in China, the exposure-response coefficients of PM(2.5) and O(3) and total mortality from Meta studies in China were used to construct local AQHI. The health risk levels of air pollution in the 5 cities were calculated and compared with the characteristics of single pollutant concentrationof PM(2.5) or O(3). Results: In the 5 cities, the average concentration of PM(2.5) was highest in Beijing (82 μg/m(3)) and lowest in Guangzhou (46 μg/m(3)). And the average concentration of O(3) was highest in Shanghai (72 μg/m(3)) and lowest in Xi' an (45 μg/m(3)). In all the cities, the average concentration of PM(2.5) was highest in winter and lowest in summer. In summer, the average concentration of O(3) was lowest. But the health risk level of AQHI showed that the 5 cities had higher frequency of low or medium risk averagely. And Beijing had the highest frequency of high risk in summer (5.69%). Xi' an had the highest frequency of extremely high risk in winter (1.63%). Conclusions: In this study, AQHI could be constructed by using air PM(2.5) and O(3) concentration data which can be obtained in many areas in China. The application of this index is scientific and feasible in China.

[Revision and prospect of "Standards for indoor air quality（GB/T 18883-2022）" in China]

The formulation and revision of the detection methods of indoor air quality standards is an important, rigorous and delicate endeavor. The standards for indoor air quality (GB/T 18883-2022) were issued by the State Administration of Market Regulation and the Standardization Administration on July 11, 2022, and implemented on February 1, 2023 by replacing indoor air quality standards (GB/T 18883-2002). The revised standard specifies hygienic requirements for physical, chemical, biological and radioactive indicators in indoor air and the corresponding test methods. This article interpreted the revision background, drafting principles, main indicators and methods, as well as the revision basis of the standards. Recommendations for the implementation of the standards are also proposed.

[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.

[Focus on cardiovascular metabolism research and guide the prevention and control of chronic diseases in the older adults]

With the acceleration of global population aging, the incidence and mortality of cardiovascular disease (CVD) among the older adults are continuously rising, posing an essential public health challenge that severely threatens their health and quality of life. In recent years, significant progress has been made in the research on epidemiological characteristics, risk factors, and prevention strategies of CVD in older adults. This review aims to summarize the current research status of CVD in the old adults, explore key factors affecting cardiovascular health, including genetic factors, lifestyle, and metabolic abnormalities, and evaluate the effectiveness of novel interventions. The goal is to provide a scientific basis for developing CVD prevention and management strategies tailored to the old adults.

[Distribution, Source and Human Exposure of Phthalic Acid Esters (PAEs) in Surface Dust in Urban Area of Xi'an City, China]

A total of 58 surface dust samples were collected in urban area of Xi'an City. High Performance Liquid Chromatography (HPLC) was used to analyze the concentrations of six phthalic acid esters (PAEs) listed as priority pollutants by United States Environmental Protection Agency (U.S. EPA). Composition, distribution, environmental sources and exposure characteristics of PAEs in the surface dust were further studied. All analyzed PAEs were detected in the surface dust. The concentration of individual PAE compounds varied from not detectable to 183.19 mg·kg^-1 and their mean concentrations decreased in the order of DEHP>DnBP >>DEP >DMP >BBP >DnOP. The total concentration of six PAEs (∑6PAEs) ranged from 0.87 to 250.30 mg·kg^-1 with an average of 40.48 mg·kg^-1, and followed the order of parks >traffic area >mixed business and traffic area >residential area >educational area >industrial area. The ∑6PAEs presented the decreasing trend along the main urban area - the second ring road - the third ring road. The results of correlation analysis, principal component analysis and cluster analysis showed that PAEs in surface dust of Xi'an City were related to the application of plasticizers, the emission of cosmetics and personal care products along with building materials and home decoration materials. The dose order of human exposure to PAEs in surface dust was the direct ingestion by hand and mouth >>dermal adsorption >inhalation via mouth and nose. Meanwhile, the intake dose of children was higher than that of adults. However, the intake dose of DnBP, DEHP, DBP and BBP was lower than the tolerable daily intake (TDI) suggested by European Union Scientific Committee for Toxicity, Ecotoxicity and the Environment (EU CSTEE) and the reference doses (RfD) proposed by U.S. EPA.

[The key problems in the population exposure assessment of hazardous chemicals accidents]

Serious accidents of hazardous chemicals can cause a variety of acute or chronic impairment in human health. The effects of hazardous chemicals on human health can be identified by carrying on population exposure assessment. Through analyzing the domestic and overseas population exposure assessment cases related to hazardous chemicals accidents, we summarized that the base and key of the population exposure assessment were to identify the characteristics of the chemicals , delimit the area and the population exposed to the chemicals, and collect the data of the monitored chemicals and the population health in the polluted area.

[Correlative factors related to the density of Meriones unguiculatus in the Meriones unguiculatus plague foci of Hebei province, 2001-2013]

OBJECTIVE

To explore the yearly, monthly and habitat-related distribution and their relations with Meriones unguiculatus density in the Hebei Meriones unguiculatus plague foci, from 2001 to 2013.

METHODS

Data related to Meriones unguiculatus was gathered through the monitoring programs set up at the national and provincial Meriones unguiculatus plague foci in Hebei province, from 2001 to 2013. According to the yearly density of Meriones unguiculatus, criteria set for the three groups under study, were as follows:'high-risk group'-when the rodent density was≥1.00 under rodents/hm(2),'warning group'-when the rodents/hm(2)>rodent density> 0.20,'standard group'-when rodents/hm(2) rodent density≤0.20 rodents/hm(2). Differences of habitats and monthly distribution among the three groups were compared, under the Kruskal-Wallis H rank sum test while their relations were under the multiple correspondence analysis.

RESULTS

The Meriones unguiculatus densities were higher than 1.00 rodents/hm(2), far above the set national standards, in the monitoring area, between 2001 and 2005. From 2005, though the rodent densities began to decrease, however, figures from 2008 to 2013 were still among 0.20 to 1.00 rodents/hm(2). The distribution of habitats in the three groups showed that the Meriones unguiculatus densities were all different in habitats and the difference was statistically significant (P<0.05). The highest median densities were all in the arable land, with maximum value of high-risk group appeared the highest (20.50 rodents/hm(2)) in the wasteland. Monthly distribution showed that the Meriones unguiculatus densities were different and the difference was statistically significant (P<0.05) in the high-risk and standard groups but not statistically significant in the warning group. Data from the multiple correspondence analysis showed that there was a strong aggregation among wasteland, in April and June, while the warning group was associated with weather in July and the arable land.

CONCLUSIONS

When the density became higher than 1.00 rodents/hm(2), the risk on animal plague increased in Hebei Meriones unguiculatus plague foci. Based on the distribution of Meriones unguiculatus, programs should be set to monitor the rodent in arable land and wasteland, in April and June, to reduce the prevalence of animals plague.

[Prediction of 6-year risk of activities of daily living disability in elderly aged 65 years and older in China]

Objective: To construct an easy-to-use risk prediction tool for 6-year risk of activities of daily living(ADL) disability among Chinese elderly aged 65 and above. Methods: A total of 34 349 elderly aged 65 and above were recruited from the Chinese Longitudinal Healthy Longevity Survey. Demographic characteristics, lifestyle and chronic diseases of the elderly were collected through face-to-face interviews. The functional status of the elderly was evaluated by the instrumental activities of daily living(IADL) scale. The mental health status of the elderly was evaluated by the Mini-Mental State Examination. The height, weight, blood pressure and other information of the subjects were obtained through physical examination and body mass index(BMI) was calculated. The ADL status was evaluated by Katz Scale at baseline and follow-up surveys. Taking ADL status as the dependent variable and the key predictors were selected from Lasso regression as the independent variables, a Cox proportional risk regression model was constructed and visualized by the nomogram tool. Area under the receiver operating characteristic curve(AUC) and calibration curve were used to evaluate the discrimination and calibration of the model. A total of 200 bootstrap resamples were used for internal validation of the model. Sensitivity analysis was used to evaluate the robustness of the model. Results: The M(Q₁, Q₃) of subjects' age as 86(75, 94) years old, of which 9 774(46.0%) were males. A total of 112 606 person-years were followed up, 4 578 cases of ADL disability occurred and the incidence density was 40.7/1 000 person-years. Cox proportional risk regression model analysis showed that older age, higher BMI, female, hypertension and history of cerebrovascular disease were associated with higher risk of ADL disability [HR(95%CI) were 1.06(1.05-1.06), 1.05(1.04-1.06), 1.17(1.10-1.25),1.07(1.01-1.13) and 1.41(1.23-1.62), respectively.]; Ethnic minorities, walking 1 km continuously, taking public transportation alone and doing housework almost every day were associated with lower risk of ADL disability [HR(95%CI): 0.71(0.62-0.80), 0.72(0.65-0.80), 0.74(0.68-0.82) and 0.69(0.64-0.74), respectively]. The AUC value of the model was 0.853, and the calibration curve showed that the predicted probability was highly consistent with the observed probability. After excluding non-intervening factors(age, sex and ethnicity), the AUC value of the model for predicting the risk of ADL disability was 0.779. The AUC values of 65-74 years old and 75 years old and above were 0.634 and 0.765, respectively. The AUC values of the model based on walking 1 km continuous and taking public transport alone in IADL and the model based on comprehensive score of IADL were 0.853 and 0.851, respectively. Conclusion: The risk prediction model of ADL disability established in this study has good performance and robustness.

[Exploring a definition of healthy longevity in Chinese population based on Delphi method]

Objective: To explore a definition of healthy longevity in the Chinese population based on the Delphi method. Methods: Through a comprehensive literature review and expert consultation, the dimensions in the definition of healthy longevity were identified, and a preliminary list of questions was created. Experts in clinical medicine, public health, basic research, and the elderly care service industry, who had been working in the field of geriatric health for at least 5 years, were invited to participate in the Delphi survey from August to December 2022. The survey questionnaires were administered via email in two rounds, and experts were asked to select the optimal options from the provided questions. The active coefficients were expressed by the response rate, and a consensus was reached when the largest number of experts agreed for single-choice questions and more than 70% agreed for multiple-choice questions. Results: In the two rounds, the active coefficients were 96.00% (24/25) and 79.17% (19/24), respectively, and a consensus was finally reached on nine items, including age, physical health, common metabolic indicators, mental health, cognitive function, functional ability, social activity, self-rated health, and subjective well-being. Following discussions among the research team and experts, a final definition of healthy longevity was determined. Healthy longevity could refer to a state of good physical, psychological, cognitive function and social adaptation, as well as subjective well-being, in individuals aged 90 and above. Specifically, individuals with healthy longevity should be free from diseases associated with high disability rates and mortality, such as stroke, cancer, and Parkinson's disease. They should also maintain reasonable levels of common non-communicable disease indicators, such as blood pressure and blood glucose, and exhibit favorable mental health and cognitive function using validated measurement tools. In addition, individuals with healthy longevity should engage in social interactions with friends and relatives, care for family members, and go out to do things. Meanwhile, with the ability to complete the visual and hearing functions of daily life and communication, and the ability to complete basic activities such as walking, eating, bathing, toileting, dressing, continence of urination, and bowel movement independently, they could rate themselves to be in good health and experience a relatively high level of life satisfaction. Conclusion: A definition of healthy longevity in the Chinese population is established through the two-round Delphi consultation.

[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.

Differential expression of a basic helix-loop-helix phosphoprotein gene, G0S8, in acute leukemia and localization to human chromosome 1q31

A basic helix-loop-helix phosphoprotein gene, G0S8, was recently isolated by differential screening of cDNA from human blood mononuclear cells stimulated with a T cell mitogen and cycloheximide. In this study, G0S8 expression was examined in normal and malignant hematopoietic cells by Northern blot analysis and reverse transcription-polymerase chain reaction (RT-PCR). G0S8 expression was observed in most fresh samples of acute myelogenous leukemia (AML) (28/30) and most cases of adult acute lymphoblastic leukemia (ALL) (9/11) regardless of clinical classification. G0S8 mRNA was also detected in all cases tested of chronic myelogenous leukemia (CML) in blast crisis. However, G0S8 expression was not detected in CML patients in chronic phase, nor in normal bone marrow or other hematopoietic cells. G0S8 has been mapped using fluorescence in situ hybridization (FISH) to human chromosome 1q31, the same site reported for the B cell homolog BL34/1R20 and within a region implicated in the development of hematological malignancies. The consistent observation of G0S8 mRNA in patient samples of acute leukemia suggests that G0S8 expression may either play a role in leukemogenesis or represent a common consequence of dysregulated growth.

[Prediction model related to 6-year risk of frailty in older adults aged 65 years or above in China]

Objective: To develop a prediction tool for 6-year incident risk of frailty among Chinese older adults aged 65 years or above. Methods: Data from the Chinese Longitudinal Healthy Longevity Survey from 2002 to 2018 was used, including 13 676 older adults aged 65 years or above who were free of frailty at baseline. Key predictors of frailty were identified via the least absolute shrinkage and selection operator (LASSO) method, and were thereafter used to predict the incident frailty based on the Cox proportional hazards regression model. The model was internally validated by 2 000 Bootstrap resamples and evaluated for the performance of discrimination and calibration using the area under the receiver operating characteristic curve (AUC) and calibration curve, respectively. The net benefit of the developed prediction tool was evaluated by decision-curve analysis. Results: The M(Q1, Q3) age and follow-up time of the participants were 81.0 (71.0, 90.0) years and 6.0 (4.1, 9.2) years, respectively. A total of 4 126 older persons (30.2%) were recorded with frailty incidents during the follow-up, with the corresponding incidence density of 41.8/1 000 person-years. A total of 15 key predictors of frailty were selected by LASSO, namely, age, sex, race, education years, meat consumption, tea drinking, performing housework, raising domestic animals, playing cards or mahjong, and baseline status of visual function, activities of the daily living score, instrumental activities of the daily living score, hypertension, heart disease, and self-rated health. The prediction model was internally validated with an AUC of 0.802, with the max Youden's index of 0.467 at a risk threshold of 19.0%. The calibration curve showed high consistency between predicted probabilities and observed proportions of frailty events. The decision curve indicated that higher net benefits could be obtained via the prediction model than did strategies based on intervention in all or none participants for any risk threshold less than 59%, and the model-based net benefit was estimated to be 0.10 at a risk threshold of 19.0%. Conclusions: The herein developed 6-year incident risk prediction model of frailty, based on easily accessible questionnaires and physical examination variables, has good predictive performance. It has application potential in identifying populations at high risk of incident frailty.