Addressing causal relationship between drinking behavior and metabolic syndrome: one-sample Mendelian randomization analysis.

AIMS: Alcohol drinking is associated with central obesity, hypertension, and hyperlipidemia, which further causes metabolic syndrome (MetS). However, prior epidemiological studies on such associations lack experimental evidence for a causal relationship. This study aims to explore the causal relationship between drinking behavior and MetS in Taiwan population by using Mendelian randomization (MR) analysis. METHODS: A cross-sectional study was conducted using the Taiwan Biobank database, which comprised 50 640 Han Chinese who were 30-70 years old without cancer from 2008 to 2020. In MR analysis, we constructed weighted and unweighted genetic risk scores by calculating SNP alleles significantly associated with alcohol drinking. We calculated odds ratios and 95% confidence interval (CI) by using a two-stage regression model. RESULTS: A total of 50 640 participants were included with a mean age of 49.5 years (SD: 1.67 years), 36.6% were men. The adjusted odds ratio (aOR) of MetS per 5% increase in the likelihood of genetic predisposition to drink based on weighted genetic risk score with adjustment was 1.11 (95% CI: 1.10, 1.12, P < .001). Analysis was also conducted by grouping the likelihood of genetic predisposition to drink based on quartiles with multivariate adjustment. Using Q1 as the reference group, the aORs of MetS for Q2, Q3, and Q4 were 1.19 (1.12, 1.27, p < .001), 1.31 (1.23, 1.40, p < .001), and 1.87 (1.75, 2.00, p < .001), respectively, for the weighted genetic risk score. CONCLUSIONS: This study shows a modest relationship between drinking behavior and MetS by using MR analysis.

Mitochondrial DNA haplogroup D and brain microstructure regulate cognitive function among community-dwelling older adults.

INTRODUCTION: Maintaining physical and cognitive function among older adults is important. These functional states are affected by mitochondria through various mechanisms, such as cellular energy production and oxidative stress control. Owing to its involvement in the relations among the brain, cognition, and physical function, mitochondrial function may be affected by mitochondrial DNA (mtDNA) haplogroups. This study explored the effect of mtDNA haplogroups and brain microstructure on physical and cognitive functions among community-dwelling older adults. METHODS: This study was a community-based cross-sectional research. A total of 128 subjects aged 65 years and older without dementia completed several assessments, including mtDNA sequencing, physical and cognitive function tests, and magnetic resonance imaging (MRI) scans. Cognitive function and impairment were assessed by the MMSE and AD8 questionnaires. mtDNA haplogroups were classified by HaploGrep 2 software, and white matter microstructural integrity was scanned by 3T MRI. RESULTS: The mean age of the subjects was 77.3 years. After the adjustment for covariates, the mtDNA haplogroup D carriers showed significantly lower mini-mental state examination (MMSE) scores than other carriers (p = 0.047). Further considering the brain microstructure, the mtDNA haplogroup D (p = 0.002) and white matter volumes in the left precuneus corrected for total intracranial volumes (p = 0.014) were found to be independently influencing factors of the MMSE scores. CONCLUSIONS: The mtDNA haplogroup D and white matter microstructure regulated the cognitive function among community-dwelling older adults. The findings provide new insights into the research gap. Scientists must further venture into this field.

Association of high-sensitivity C-reactive protein and diabetic nephropathy in patients with type 2 diabetes: a Mendelian randomization study.

INTRODUCTION: Observational studies support the relationship between C-reactive protein (CRP) level and diabetic nephropathy (DN) in patients with diabetes. The research question regarding whether the relationship between serum high-sensitivity C-reactive protein (hsCRP) level and DN is causal lacks experimental evidence. Therefore, this study aimed to evaluate the causality between hsCRP and DN based on Mendelian randomization (MR) analysis. RESEARCH DESIGN AND METHODS: A total of 2332 participants with type 2 diabetes from the Taiwan Biobank database was analyzed. Genetic risk scores (GRSs), which comprise four validated CRP loci as two instrumental variables, were calculated as unweighted and weighted scores to evaluate the causal relationship of hsCRP with DN risk. The two-stage regression model was used to estimate OR and 95% CI. RESULTS: The analyses of the observational study showed that the hsCRP level was significantly associated with DN after multivariate adjustment (adjusted OR 1.15; 95% CI 1.01 to 1.32). Unweighted/weighted GRSs for log-transformed hsCRP satisfied MR assumptions 1 and 3, respectively; that is, a significant association with hsCRP was observed but that with DN was absent (adjusted OR 1.00, 95% CI 0.92 to 1.09; 1.00, 0.72 to 1.39, respectively). The MR analyses demonstrated that a 1-unit increase in the log-transformed genetically predicted hsCRP by unweighted and weighted GRSs was associated with DN, demonstrating ORs of 1.80 (95% CI 1.51 to 2.14) and 1.67 (95% CI 1.40 to 1.98), respectively. CONCLUSIONS: The current study provided experimental evidence that hsCRP level was causally related to DN. These findings suggest that the elevated hsCRP may be a causal risk factor for DN in patients with type 2 diabetes.

Risk prediction of nephropathy by integrating clinical and genetic information among adult patients with type 2 diabetes.

AIMS: Diabetic nephropathy (DN) is a major healthcare challenge. We developed and internally and externally validated a risk prediction model of DN by integrating clinical factors and SNPs from genes of multiple CKD-related pathways in the Han Chinese population. MATERIALS AND METHODS: A total of 1526 patients with type 2 diabetes were randomly allocated into derivation (n = 1019) or validation (n = 507) sets. External validation was performed with 3899 participants from the Taiwan Biobank. We selected 66 SNPs identified from literature review for building our weighted genetic risk score (wGRS). The steps for prediction model development integrating clinical and genetic information were based on the Framingham Heart Study. RESULTS: The AUROC (95% CI) for this DN prediction model with combined clinical factors and wGRS was 0.81 (0.78, 0.84) in the derivation set. Furthermore, by directly using the information of these 66 SNPs, our final prediction model had AUROC values of 0.85 (0.82, 0.87), 0.89 (0.86, 0.91), and 0.77 (0.74, 0.80) in the derivation, internal validation, and external validation sets, respectively. Under the combined model, the results with a cutoff point of 30% showed 70.91% sensitivity, 67.84% specificity, 51.54% positive predictive value, and 82.86% negative predictive value. CONCLUSIONS: We developed and internally and externally validated a model with clinical factors and SNPs from genes of multiple CKD-related pathways to predict DN in Taiwan. This model can be used in clinical risk management practice as a screening tool to identify persons who are genetically predisposed to DN for early intervention and prevention.

Mitochondrial DNA haplogroups affect physical performances in Han older adults: an 8-year follow-up prospective cohort study.

AIM: The objective of this study was to explore the association between mitochondrial DNA (mtDNA) haplogroups and physical performances in Han older adults. METHODS: This study was an 8-year follow-up prospective cohort study. A total of 104 Han older adults completed the measurements of the 6-min walk test, grip strength and mitochondrial DNA sequencing. The mtDNA haplogroups were classified by using HaploGrep2 software. We used the mixed model to analyze the longitudinal effect of mtDNA haplogroups on physical performance tests among three waves of data. RESULTS: The mean age at wave 3 among men and women were 78.3 and 77.2 years, respectively. The overall proportions of mtDNA haplogroups in this study population was 26.9% F, 21.2% M, 15.4% R, 14.4% D, 8.7% B and others. After adjusted for age, sex, ethnicity, body mass index and exercise, the interaction of mtDNA haplogroup M and waves significantly affected the 6-min walk distance. Notably, the adjusted mean of the 6-min walk distance among the group of mtDNA haplogroup M was significantly lower than other haplogroups at wave 3. The adjusted mean of grip strength among the group of mtDNA haplogroup R was significantly higher than other haplogroups at wave 3. CONCLUSIONS: This finding suggests that mtDNA haplogroups might have effects on the 6-min walk test and grip strength in Han older adults, although studies of the physical performance of older adults with larger sample sizes are necessary to further substantiate these findings. Geriatr Gerontol Int 2021; 21: 166-171.

Independent associations of urinary albumin-to-creatinine ratio and serum cystatin C with carotid intima-media thickness in community-living Taiwanese adults.

BACKGROUND: Renal function is a key factor of cardiovascular disease. Carotid intima-media thickness (IMT) has been widely used as a marker of early subclinical atherosclerosis. The determinants of cystatin C, a novel marker of renal function, have not been extensively studied in the Asian population. This study aimed to assess the determinants of cystatin C and explore whether carotid thickening was associated with urinary albumin-creatinine ratio and cystatin C in community-living Taiwanese adults. METHODS: A cross-sectional study was conducted on participants from Taichung City, Taiwan. All the participants underwent carotid ultrasonography. Carotid IMT-mean and IMT-maximum were derived. Kidney biomarkers were measured on the basis of urinary albumin-to-creatinine ratio (ACR) and cystatin C. Multiple linear regression analysis was used. RESULTS: A total of 1032 individuals were recruited, and 469 (45.44%) of them were men. An increased cystatin C level was significantly associated with older age, male gender, lack of physical activity, low HDL cholesterol, abdominal obesity, high hs-CRP, and high ACR. The multivariate-adjusted mean carotid IMT-mean and IMT-maximum values significantly increased by 80.49 and 195.23 µm for every one unit of increase in cystatin C level and by 0.07 and 0.14 µm for every one unit of increase in ACR, respectively (all p < 0.001 except ACR on IMT-maximum with p < 0.01). Lack of physical activity, low HDL, abdominal obesity, high hs-CRP, and high ACR were the determinants of cystatin C. CONCLUSION: Cystatin C and ACR were strongly and linearly associated with carotid thickening, a marker of subclinical atherosclerosis.

Interactions among IGF-1, AKT2, FOXO1, and FOXO3 variations and between genes and physical activities on physical performance in community-dwelling elders.

This study assessed the interactions among IGF-1, AKT2, FOXO1, and FOXO3 variations and the interactions of gene and physical activity on handgrip strength, arm muscle mass-adjusted handgrip (armGrip), gait speed (GS), timed up and go (TUG), and leg press strength (LPS). Nine single nucleotide polymorphisms (SNPs) containing three IGF-1 SNPs (rs6214, rs5742692, and rs35767), two AKT2 SNPs (rs892119 and rs35817154), two FOXO1 SNPs (rs17446593 and rs10507486), and two FOXO3 SNPs (rs9480865 and rs2153960) were genotyped in 472 unrelated elders with a mean age of 73.8 years. We observed significant interactions of IGF-1 SNP rs6214 and rs35767 with regular physical activity on TUG and GS; and AKT2 SNP rs892119 and FOXO3 SNP rs9480865 with regular physical activity on armGrip. Genotype GG of IGF-1 rs6214 and rs35767 in individuals without regular physical activity had poor performance in TUG and GS, as well as GG of AKT2 rs892119 decreased armGrip in individuals without regular physical activity. After FDR adjustment, no significant gene-gene interactions were found. A sedentary lifestyle may increase the risk of impairing physical performance and regular physical activity is a remedy for sarcopenia, even a little regular physical activity can overcome carrying some risk alleles in this pathway.

Effects of concurrent aerobic and resistance exercise in frail and pre-frail older adults: A randomized trial of supervised versus home-based programs.

BACKGROUND: This study aimed to investigate the effects of supervised and home-based exercise programs on older people with frailty or pre-frailty. METHODS: A total of 146 community-dwelling participants aged 65 and older who were prefrail or frail were randomly allocated into supervised exercise (N = 74) and home exercise (N = 72) groups. The 3-month supervised exercise training consisted of 3 exercise sessions per week, was performed at a hospital and supervised by a physical therapist. Home exercise participants took instructions on exercise and illustrated exercise handouts. The baseline and 3-month follow-up measurements included body composition, strength of selected upper and lower limb muscle groups, grip and leg press strengths, and five physical performance tests. Mixed-model repeated-measures analysis was applied to determine whether two groups differ in terms of changes before and after the intervention and to compare within-group improvements. RESULTS: After 3 months of supervised or home-based exercise, the average number of frailty criteria met and fat percentage decreased significantly. Strength of knee extensors, knee flexors and leg press improved significantly in supervised exercise group. In home-based exercise group, the strength of all muscle groups tested improved significantly, except for leg press strength. Walking speed improved in both groups, and timed-up-and-go and timed chair rise tests improved significantly only in supervised exercise group. CONCLUSIONS: Three-month supervised or home-based exercise improved walking speed and strength of the limb muscles. Supervised group showed more improvements in the physical performance tests compared with home-based exercise group.

Subclinical Atherosclerosis Markers of Carotid Intima-Media Thickness, Carotid Plaques, Carotid Stenosis, and Mortality in Community-Dwelling Adults.

Carotid intima-media thickness (IMT), plaque, and stenosis are widely used as early surrogate markers of subclinical atherosclerosis and strong predictors of future deaths and cardiovascular events. Albuminuria is an indicator of generalized endothelial dysfunction that speeds up atherosclerosis. However, previous studies reporting these associations cannot rule out the confounding effect of albuminuria. We aimed to examine the independent and joint relationships between IMT markers and 10-year mortality in community-dwelling Taiwanese adults. This work was a community-based prospective cohort study consisting of 2956 adults aged at least 30 years recruited in 2007 and followed up through 2019. Cox proportional hazard regression models were used to examine associations of these subclinical atherosclerosis markers with mortality. During an average of 9.41 years of follow up, 242 deaths occurred. The mortality rate was 8.70 per 1000 person-years. Compared with those with carotid IMT less than 1.0 mm, persons with severely increased carotid IMT (≥2.0 mm) had an increased risk for death (hazard ratio (HR): 1.79; 95% confidence interval (CI): 1.07, 3.00). Compared with those without carotid plaque, persons with carotid plaque were more likely to have an increased risk for death (1.65; 1.21-2.32). Compared with those with carotid stenosis less than 25%, persons with carotid stenosis of 25-36% had a significant increased risk for death (1.57; 1.12-2.22). Considering these three IMT markers along with the traditional risk factors (c-statistic: 0.85) significantly increased their predictive ability of mortality compared with any individual variable's predictive ability (all p-values < 0.001 for comparisons of c-statistic values). Carotid IMT measures, including IMT thickness, carotid plaque, and carotid stenosis were significant independent predictors of mortality. Our study supports evidence of blood pressure-related media thickening markers to assess future mortality risks in Chinese adults of general population.

Cognitive function and its transitions in predicting all-cause mortality among urban community-dwelling older adults.

BACKGROUND: Cognitive impairment is accompanied with high rates of comorbid conditions, leading ultimately to death. Few studies examine the relation between cognitive transition and mortality, especially in Asian population. This study evaluated baseline cognition and cognitive transition in relation to all-cause mortality among community-dwelling older adults. METHODS: We conducted a community-based prospective cohort study among 921 participants of Taichung Community Health Study for Elders in 2009. Cognitive function was evaluated by the Mini-Mental State Examination. Cognitive impairment was considered if the total score is less than 27, 24, and 21 for a participant's educational level of more than 6 years, equal or less than 6 years, and illiteracy, respectively. One-year transition in cognitive function was obtained among 517 individuals who were assessed in both 2009 and 2010. Mortality was followed up until 2016. Cox proportional hazards models were applied to estimate the adjusted hazard ratios of mortality for baseline cognitive impairment and one-year transition in cognitive status. RESULTS: After a follow-up of 6.62 years, 160 deaths were recorded. The multivariate adjusted hazard ratio (95% confidence interval) for baseline cognitive impairment was 2.08 (1.43, 3.01). Significantly increased mortality risk was observed for cognitively impaired-normal and impaired-impaired subgroups over 1 year as compared with those who remained normal [2.87 (1.25, 6.56) and 3.79 (1.64, 8.73), respectively]. The area under the receiver operating characteristic curves demonstrated that baseline cognition and one-year cognitive transition had no differential predictive ability for mortality. Besides, there was an interaction of cognitive impairment and frailty, with an additive mortality risk [5.41 (3.14, 9.35)] for the elders who presented with both. CONCLUSION: Baseline cognitive impairment rather than one-year progression is associated with mortality in a six-year follow-up on older adults.

Evaluation of single nucleotide polymorphisms in 6 candidate genes and carotid intima-media thickness in community-dwelling residents.

Evidence suggests the existence of association between a large panel of modifiable biomarkers representing inflammation, coagulation, paraoxonase, and endothelial activation pathways and carotid atherosclerosis. Thus, this study investigated whether CRP, FGA, FGB, FGG, PON1, and EDNRA gene variants affected plasma hs-CRP, fibrinogen levels, and thickness of carotid intima media thickness (IMT). Nineteen single-nucleotide polymorphisms of CRP, FGA, FGB, FGG, PON1, and EDNRA genes were examined in 480 participants from 160 families. Carotid IMT was measured by ultrasound. Generalized linear models with generalized estimating equation were utilized to consider the dependence of subjects within families. In the recessive model, homozygotes for the minor alleles of rs1800789, rs1800790 and rs4220 SNPs in FGB gene indicated a reduced risk of IMT (Exp. ß = 0.89, 0.89, 0.88), which remained significant after adjustment for confounding factors. Significant interaction effects between CRP SNP rs1130864 and rs3093059 and gender for IMT were observed with a significant association in men only. Men carrying minor-minor genotype of CRP SNP rs1130864 and rs3093059 had 0.70- and 0.78-fold lower IMT than men carrying minor-major/major-major genotype. We also observed that the interaction of CRP SNP rs1130864 and rs3093059 with obesity on IMT, hs-CRP and fibrinogen levels. These results support the hypothesis that inflammatory genes are involved in atherosclerosis, most likely via complex gene-gender and gene-obesity interactions.

Important gene-gene interaction of TNF-α and VDR on osteoporosis in community-dwelling elders.

Gene effects on osteoporosis have been studied separately and may have been masked by gene-gene and gene-environment interactions. We evaluated gene-gene and gene-physical activity interactions of the variants of tumor necrosis factor-α (TNF-α) and vitamin D receptor (VDR) genes on osteoporosis. A total of 472 elders were included. Seven variants (TNF-α: rs1799964, rs1800629, rs3093662; VDR: rs7975232, rs1544410, rs2239185, rs3782905) were genotyped. Bone mineral densities of the lumbar spine, femoral neck, and total hip were measured by dual-energy X-ray absorptiometry. Predictive models' ability to discriminate osteoporosis status was evaluated by areas under the receiver operating characteristics (AUROC) curve. After multivariable adjustment, significant interactions of TNF-α rs1800629 and VDR rs3782905 were observed on overall and lumbar spine osteoporosis. In elderly women, we found that those carrying the CG/CC genotype of VDR rs3782905 were significantly associated with increased odds of overall osteoporosis compared with those carrying the GG genotype of VDR rs3782905 among those carrying TNF-α rs1800629 GG genotype. The adjusted odds ratios (ORs) for VDR rs3782905 CG/CC genotype in elderly women carrying TNF-α rs1800629 AG/AA and GG genotypes were 0.1 (0.01, 0.98) and 3.54 (1.51, 8.30), respectively. We observed significant differences in AUROCs between the model with traditional covariates plus variants and their interaction term and the model with traditional covariates only (AUROCs: 0.77 and 0.81; p = 0.028). Although the sample size of this study may have been relatively small, our results suggest that the interaction of the CG/CC genotype of VDR rs3782905 with TNF-α rs1800629 GG genotype was associated with increased odds of overall and lumbar spine osteoporosis in elderly women.

Genetic risk score for risk prediction of diabetic nephropathy in Han Chinese type 2 diabetes patients.

We evaluated whether genetic information could offer improvement on risk prediction of diabetic nephropathy (DN) while adding susceptibility variants into a risk prediction model with conventional risk factors in Han Chinese type 2 diabetes patients. A total of 995 (including 246 DN cases) and 519 (including 179 DN cases) type 2 diabetes patients were included in derivation and validation sets, respectively. A genetic risk score (GRS) was constructed with DN susceptibility variants based on findings of our previous genome-wide association study. In derivation set, areas under the receiver operating characteristics (AUROC) curve (95% CI) for model with clinical risk factors only, model with GRS only, and model with clinical risk factors and GRS were 0.75 (0.72-0.78), 0.64 (0.60-0.68), and 0.78 (0.75-0.81), respectively. In external validation sample, AUROC for model combining conventional risk factors and GRS was 0.70 (0.65-0.74). Additionally, the net reclassification improvement was 9.98% (P = 0.001) when the GRS was added to the prediction model of a set of clinical risk factors. This prediction model enabled us to confirm the importance of GRS combined with clinical factors in predicting the risk of DN and enhanced identification of high-risk individuals for appropriate management of DN for intervention.

Relationship among urinary advanced glycation-end products, skeletal muscle mass and physical performance in community-dwelling older adults.

AIM: Advanced glycation end-products are important factors in muscle function and physical performance among older adults. However, the association between sarcopenia and urinary carboxymethyl-lysine (uCML) levels remains unclear. The present study aimed to investigate the relationship among uCML levels, skeletal muscle mass, physical performance and sarcopenia among community-dwelling older adults. METHODS: This work was a community-based cross-sectional study. The participants were recruited from the Taichung Community Health Study-Elderly and were followed up until 2017. A total of 104 participants underwent dual-energy X-ray absorptiometry examination, physical performance tests and measurement of uCML levels. After the natural log transformation of the uCML levels, Pearson's correlation coefficient and a general linear model were used for statistical analysis. RESULTS: The mean uCML levels of older men and women were 1.34 µg/mg and 1.63 µg/mg creatinine, respectively. After multivariate adjustment, grip strength among older women significantly decreased as uCML levels increased. Participants with uCML levels and Timed Up and Go test values higher than the median had a 13.76-fold risk of acquiring sarcopenia compared with those whose corresponding variables were lower than the median after adjusting for age, sex, body fat percentage, and serum creatinine and blood urea nitrogen levels. CONCLUSIONS: uCML levels were negatively associated with grip strength among older women. The joint association of uCML and Timed Up and Go test values was correlated with the risk of acquiring sarcopenia among older adults. This finding suggests that uCML levels can be used as a biomarker for screening sarcopenia and as a strategy for treating sarcopenia. Geriatr Gerontol Int 2019; 19: 1017-1022.

Combined Effects of Having Sleep Problems and Taking Sleeping Pills on the Skeletal Muscle Mass and Performance of Community-Dwelling Elders.

This study aimed to explore the combined effects of having sleep problems and taking sleeping pills on the skeletal muscle mass and performance of community-dwelling elders. A total of 826 participants who have complete information regarding dual-energy X-ray absorptiometry examination, questionnaire, and physical performance tests were included. The status of having sleep problems and taking sleeping pills was assessed with a self-reported questionnaire. The prevalence rates of sleep problems among older men and women were 37.4% and 54.5%, respectively. After multivariate adjustment, the mean height-adjusted skeletal muscle indices for elders having sleep problems and taking sleeping pills among men and women were 7.29 and 5.66 kg/m2, respectively, which were lower than those without sleep problems (P = 0.0021 and P = 0.0175). The performance of the older men having sleep problems and taking sleeping pills in terms of walking speed, grip strength, and number of squats, was poorer than those of the older men without sleep problems. The status of having sleep problems and taking sleeping pills was correlated with low skeletal muscle mass and poor physical performance in community-dwelling elders. These findings suggest that having sleep problems and taking sleeping pills are associated with having sarcopenia among community elderly.

Frailty, transition in frailty status and all-cause mortality in older adults of a Taichung community-based population.

BACKGROUND: Previous studies have reported the associations of frailty phenotype or its components with mortality. However, studies that explored the effects of transition in frailty status on mortality were far less in Asian or Chinese. The aim of this study was to evaluate baseline frailty status and one-year change of frailty status in relation to all-cause mortality in Taiwanese community-dwelling older adults who participated in the Taichung Community Health Study for Elders. METHODS: We conducted a community-based prospective cohort study. A total of 921 community-dwelling elderly men and women aged 65-99 years in Taichung City were enrolled in 2009-2010 and were followed up through 2016. We adopted the definition of frailty proposed by Fried et al., including five components: shrinking, weakness, poor endurance and energy, slowness, and low physical activity. Cox proportional hazards models were used to determine adjusted hazard ratios (HRs) of mortality with 95% confidence intervals (CIs) for frailty at baseline and one-year change in frailty status. RESULTS: There were 160 deaths during the follow-up period. The mortality rates in groups of robust and frail were 20.26 and 84.66 per 1000 person-years respectively. After multivariate adjustment, the HR (CIs) for baseline frailty was 2.67 (1.73-4.12). Poor endurance and energy [1.88 (1.03-3.42)], slowness [2.60 (1.76-3.83)] and weakness [1.65 (1.16-2.33)] were found to be predictors of mortality. Increased risks in mortality for subgroups of robust-to-frail [2.76 (1.22-6.27)], frail-to-robust [3.87 (1.63, 9.19)], and frail-to-frail [4.08 (1.92-8.66)] over one-year period were observed compared with those remaining robust. CONCLUSION: Baseline frailty status and one-year change in frailty status are associated with 6-year all-cause mortality among Taiwanese elderly adults. Frailty may be useful for identifying older adults at high risks for mortality prevention.

Gene-physical activity interactions in lower extremity performance: inflammatory genes CRP, TNF-α, and LTA in community-dwelling elders.

We assessed gene-gene and gene-physical activity interactions of polymorphisms in C-reactive protein (CRP), tumor necrosis factor-α (TNF-α), and lymphotoxin α (LTA) genes on lower extremity performance in community-dwelling elders in Taiwan. Five SNPs (rs1205, rs1130864, rs1800947, rs2794520, and rs3093059) of CRP gene, three SNPs (rs909253, rs1041981, and rs2239704) of LTA gene, and three SNPs (rs3093662, rs1800629, and rs1799964) of TNF-α gene of 472 unrelated elders were genotyped. Lower extremity performance included timed up-and-go test (TUG), walking speed, weight-adjusted leg press (waLP), and timed chair stand (TCS). We detected significant interactions between physical activity with CRP rs2794520, rs1205, and rs3093059; LTA rs909253 and rs1041981; and TNF-α rs1799964 for TCS in women after covariate adjustment (all P < 0.05). In men, significant interactions between physical activity with CRP rs2794520, rs1205, and rs3093059; and LTA rs909253 and rs1041981 for TUG; with CRP rs2794520, rs1205, rs1130864, and rs3093059; and LTA rs909253 and rs1041981 for walking speed; and with TNF-α rs3093662 for waLP after covariate adjustment (all P < 0.05). These variants also significantly interacted with physical activity on TCS in women and on walking speed in men. These results show inflammatory genes are involved in lower extremity performance, likely via gene-physical activity interactions.

The joint association of insulin sensitivity and physical activity on the skeletal muscle mass and performance in community-dwelling older adults.

BACKGROUND: Many well-known risk factors that may lead to sarcopenia are already discovered. However, their combined effects on sarcopenia components remain unclear. This study aims to explore the joint association of physical activity and insulin sensitivity on skeletal muscle mass and performance of Taiwanese elder people from a metropolitan community. METHODS: The study sample involved 844 elders who were examined through dual energy X-ray absorptiometry and who underwent tests for fasting blood glucose and serum insulin level. The homeostasis model assessment (HOMA-IR) equation estimated insulin sensitivity. Physical performance was assessed by grip strength and walking speed, while physical activity status was assessed using the questionnaires answered by the participants. RESULTS: After multivariate adjustment, the mean height- and weight-adjusted skeletal muscle indexes (SMIs) for old people in the highest tertile of HOMA-IR values were 6.7kg/m2 and 27.9%, respectively, which were significantly lower than those of old people in the lowest tertile of HOMA-IR values. Compared with physically active elders with the lowest tertile of HOMA-IR values, the physically inactive elders with the highest tertile of HOMA-IR values had significantly low means in the height-adjusted SMI, weight-adjusted SMI, gait speed, and grip strength (0.25kg/m2 [p=0.0046], 0.97% [p=0.0068], 0.24m/s [p<0.0001], and 2.37kg [p=0.0085], respectively). CONCLUSION: Our study identified the joint associations of physical inactivity and low insulin sensitivity level on SMI, gait speed, and grip strength. The results provide new information for sarcopenia screening program that target elders who are predisposed to have physical dysfunction in old adults living in community.

Associations of TNF-α and IL-6 polymorphisms with osteoporosis through joint effects and interactions with LEPR gene in Taiwan: Taichung Community Health Study for Elders (TCHS-E).

Osteoporosis (OST) is a complex multifactorial disease considered to result from interactions of multiple gene and environmental factors. Tumor necrosis factor (TNF)-α and interleukin (IL)-6 are pleiotropic cytokines essential for bone remodeling; and hormone leptin has immunomodulatory effects that stimulate the synthesis of IL-6 and TNF-α. Leptin is involved in the modulation of bone growth and turnover; and its actions are bound by leptin receptor (LEPR). Prior studies evaluated the effects of TNF-α, IL-6, and LEPR gene polymorphisms separately on bone mineral densities (BMD) or OST. In this study, we assessed the roles of TNF-α and IL-6 gene polymorphisms in OST through joint effects and interactions with LEPR gene. We also evaluated possible joint effects and interactions between these polymorphisms and physical activity. Ten tag-SNPs (rs1799964, rs1800629, rs3093662 in TNF-α; rs1880243, rs1800796, rs1554606 in IL-6; and rs1751492, rs8179183, rs1805096, rs1892534 in LEPR) were used to genotype 103 OST cases and 369 controls. BMD of lumbar spine (LS), femoral neck (FN), and total hip (TH) were measured by dual-energy X-ray absorptiometry. Our data showed that TNF-α and IL-6 polymorphisms were associated with overall and site-specific OST in both sexes, and that these associations were dependent on rs1805096 and rs1892534 genotypes of LEPR. In men, LEPR A-G-G-G haplotype was associated with FN OST (OR 4.65, 95 % CI 1.61-13.40, p = 0.004). Genotype AA/AG of LEPR rs1751492 was associated with overall and FN OST in women without physical activity, but not in women with physical activity (p < 0.05 for interaction between physical activity and LEPR rs1751492). In men, we detected significant interactions of IL-6 rs1800796 with LEPR rs1805096 and rs1892534 for FN and TH OST (all p < 0.05). Our data indicate that LEPR gene may play joint and interactive roles with TNF-α and IL-6 genes and physical inactivity in development of OST. Haplotype analyses revealed that the correlations tended to be prominent in men with FN OST.

Joint effect of gene-physical activity and the interactions among CRP, TNF-α, and LTA polymorphisms on serum CRP, TNF-α levels, and handgrip strength in community-dwelling elders in Taiwan - TCHS-E.

This study assesses interactions of tumor necrosis factor α (TNF-α) gene polymorphisms with C-reactive protein (CRP) or lymphotoxin α (LTA) gene on serum CRP and TNF-α levels and handgrip strength. Eleven single nucleotide polymorphisms (SNPs), including rs2794520, rs1205, rs1130864, rs1800947, and rs3093059 in CRP; rs1799964, rs1800629, and rs3093662 in TNF-α; and rs2239704, rs909253, and rs1041981 in LTA, were genotyped in 472 unrelated elders (mean age 73.8 years). Among elders with TNF-α rs1799964 AA genotype, adjusted mean difference for handgrip strength decreased by -2.60 (-4.82, -0.38) and -2.51 kg (-4.75, -0.28) for LTA rs909253 and rs1041981 in women and by -2.39 kg (-3.98, -0.81) for CRP rs3093059 in men. Among elders with TNF-α rs1799964 AA genotype, adjusted mean ratios for hs-CRP levels increased by 2.32 (1.38, 3.90) and 2.27 (1.35, 3.84) for both CRP rs909253 and rs1041981 in women. The A-A-C LTA haplotype was associated with TNF-α levels that were 1.55 times higher than those of the C-G-A haplotype (P = 0.005). The joint effects of SNPs (the rs1800947 or rs3093059 of CRP, rs1799964 or rs1800629 of TNF-α, and rs909253 or rs1041981 of LTA) and physical inactivity appeared to have greater magnitude of decreased handgrip strength than main effects of these SNPs and physical inactivity. Our data showed that significant interactions of TNF-αrs1799964 and LTA rs909253 were observed. Moreover, joint effects of these CRP, TNF-α, and LTA risk alleles with physical inactivity in elders were observed, suggesting that physical activity may modulate effects of genotypes on handgrip strength.