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1.
Br J Clin Pharmacol ; 83(10): 2292-2302, 2017 Oct.
Article in English | MEDLINE | ID: mdl-28589543

ABSTRACT

AIMS: To investigate the association between use of ß-blockers and ß-blocker characteristics - selectivity, lipid solubility, intrinsic sympathetic activity (ISA) and CYP2D6 enzyme metabolism - and fall risk. METHODS: Data from two prospective studies were used, including community-dwelling individuals, n = 7662 (the Rotterdam Study) and 2407 (B-PROOF), all aged ≥55 years. Fall incidents were recorded prospectively. Time-varying ß-blocker use was determined using pharmacy dispensing records. Cox proportional hazard models adjusted for age and sex were applied to determine the association between ß-blocker use, their characteristics - selectivity, lipid solubility, ISA and CYP2D6 enzyme metabolism - and fall risk. The results of the studies were combined using meta-analyses. RESULTS: In total 2917 participants encountered a fall during a total follow-up time of 89 529 years. Meta-analysis indicated no association between use of any ß-blocker, compared to nonuse, and fall risk, hazard ratio (HR) = 0.97 [95% confidence interval (CI) 0.88-1.06]. Use of a selective ß-blocker was also not associated with fall risk, HR = 0.92 (95%CI 0.83-1.01). Use of a nonselective ß-blocker was associated with an increased fall risk, HR = 1.22 (95%CI 1.01-1.48). Other ß-blocker characteristics including lipid solubility and CYP2D6 enzyme metabolism were not associated with fall risk. CONCLUSION: Our study suggests that use of a nonselective ß-blocker, contrary to selective ß-blockers, is associated with an increased fall risk in an older population. In clinical practice, ß-blockers have been shown effective for a variety of cardiovascular indications. However, fall risk should be considered when prescribing a ß-blocker in this age group, and the pros and cons for ß-blocker classes should be taken into consideration.


Subject(s)
Accidental Falls/statistics & numerical data , Adrenergic beta-Antagonists/pharmacology , Cytochrome P-450 CYP2D6/metabolism , Age Factors , Aged , Aged, 80 and over , Bradycardia/chemically induced , Bradycardia/complications , Cardiac Output/drug effects , Cytochrome P-450 CYP2D6/genetics , Dizziness/chemically induced , Dizziness/complications , Female , Humans , Hypotension/chemically induced , Hypotension/complications , Male , Middle Aged , Proportional Hazards Models , Prospective Studies , Risk Factors , Sympathetic Nervous System/drug effects
2.
Calcif Tissue Int ; 98(1): 18-27, 2016 Jan.
Article in English | MEDLINE | ID: mdl-26412463

ABSTRACT

Elevated homocysteine concentrations are associated with a decline in physical function in elderly persons. Homocysteine-lowering therapy may slow down this decline. This study aimed to examine the effect of a 2-year intervention of vitamin B12 and folic acid supplementation on physical performance, handgrip strength, and risk of falling in elderly subjects in a double-blind, randomized placebo-controlled trial. Participants aged ≥65 years with elevated plasma homocysteine concentrations [12-50 µmol/L (n = 2919)] were randomly assigned to daily supplementation of 500 µg vitamin B12, 400 µg folic acid, and 600 IU vitamin D3, or to placebo with 600 IU vitamin D3. Physical performance (range 0-12) and handgrip strength (kg) were measured at baseline and after 2 years. Falls were reported prospectively on a research calendar. Intention-to-treat (primary) and per-protocol (secondary) analyses were performed. Physical performance level and handgrip strength significantly decreased during the follow-up period, but this decline did not differ between groups. Moreover, time to first fall was not significantly different (HR: 1.0, 95% CI 0.9-1.2). Secondary analyses on a per-protocol base identified an interaction effect with age on physical performance. In addition, the treatment was associated with higher follow-up scores on the walking test (cumulative OR: 1.3, 95% CI 1.1-1.5). Two-year supplementation of vitamin B12 and folic acid was neither effective in reducing the age-related decline in physical performance and handgrip strength, nor in the prevention of falling in elderly persons. Despite the overall null-effect, the results provide indications for a positive effect of the intervention on gait, as well as on physical performance among compliant persons >80 years. These effects should be further tested in future studies.


Subject(s)
Accidental Falls/statistics & numerical data , Folic Acid/administration & dosage , Hand Strength/physiology , Motor Activity/drug effects , Vitamin B 12/administration & dosage , Accidental Falls/prevention & control , Aged , Aged, 80 and over , Aging/drug effects , Aging/physiology , Dietary Supplements , Female , Homocysteine/blood , Humans , Male , Osteoporotic Fractures/epidemiology , Physical Fitness
3.
Vasc Med ; 21(2): 91-8, 2016 Apr.
Article in English | MEDLINE | ID: mdl-26774115

ABSTRACT

B-vitamin trials failed to demonstrate beneficial effects on cardiovascular outcomes, but hyperhomocysteinemia still stands out as an independent cardiovascular risk factor, particularly in elderly individuals. B-vitamins may influence early vascular dysfunction, such as endothelial dysfunction, or may have adverse effects, for example on inflammation. We investigated the effect of B-vitamins on endothelial function and inflammation within an interventional study. This study was conducted within the framework of the B-PROOF trial, which included 2919 hyperhomocysteinemic elderly individuals, who received daily vitamin B12 (500 µg) and folic acid (400 µg) or placebo for 2 years. Using an electrochemiluminescence platform, we measured intercellular adhesion molecule 1 (ICAM-1), vascular adhesion molecule 1 (VCAM-1), serum amyloid A (SAA), vascular endothelial growth factor (VEGF) and C-reactive protein (CRP) at baseline and follow-up in a subsample of 522 participants (271 intervention group; 251 placebo). Treatment effects were analyzed with ANCOVA. The participants had a mean age of 72 years, and 55% of them were male. At the 2-year follow-up, B-vitamins did not change the ICAM-1 (+36% change in the intervention group versus +32% change in the placebo group; p = 0.72), VCAM-1 (+27% vs +25%; p = 0.39), VEGF (-1% vs +4%; p = 0.40), SAA (+34% vs +38%; p = 0.85) or CRP levels (+26% vs +36%; p = 0.70) as compared to placebo. In conclusion, in elderly patients with hyperhomocysteinemia, vitamin B12 and folic acid are unlikely to influence either endothelial function or low-grade systemic inflammation. ClinicalTrials.gov Identifier: NCT00696514.


Subject(s)
Dietary Supplements , Endothelium, Vascular/drug effects , Folic Acid/therapeutic use , Homocysteine/blood , Hyperhomocysteinemia/drug therapy , Inflammation Mediators/blood , Inflammation/drug therapy , Vitamin B 12/therapeutic use , Age Factors , Aged , Aged, 80 and over , Analysis of Variance , Biomarkers/blood , Double-Blind Method , Drug Combinations , Endothelium, Vascular/metabolism , Endothelium, Vascular/physiopathology , Female , Humans , Hyperhomocysteinemia/blood , Hyperhomocysteinemia/diagnosis , Hyperhomocysteinemia/physiopathology , Inflammation/blood , Inflammation/diagnosis , Inflammation/physiopathology , Male , Netherlands , Time Factors , Treatment Outcome
4.
Calcif Tissue Int ; 96(5): 401-9, 2015 May.
Article in English | MEDLINE | ID: mdl-25712255

ABSTRACT

High plasma homocysteine (Hcy) levels are associated with increased osteoporotic fracture incidence. However, the mechanism remains unclear. We investigated the effect of Hcy-lowering vitamin B12 and folic acid treatment on bone mineral density (BMD) and calcaneal quantitative ultrasound (QUS) parameters. This randomized, double-blind, placebo-controlled trial included participants aged ≥65 years with plasma Hcy levels between 12 and 50 µmol/L. The intervention comprised 2-year supplementation with either a combination of 500 µg B12, 400 µg folic acid, and 600 IU vitamin D or placebo with 600 IU vitamin D only. In total, 1111 participants underwent repeated dual-energy X-ray assessment and 1165 participants underwent QUS. Femoral neck (FN) BMD, lumbar spine (LS) BMD, calcaneal broadband ultrasound attenuation (BUA), and calcaneal speed of sound (SOS) were assessed. After 2 years, FN-BMD and BUA had significantly decreased, while LS-BMD significantly increased (all p < 0.01) and SOS did not change in either treatment arm. No statistically significant differences between the intervention and placebo group were present for FN-BMD (p = 0.24), LS-BMD (p = 0.16), SOS (p = 0.67), and BUA (p = 0.96). However, exploratory subgroup analyses revealed a small positive effect of the intervention on BUA at follow-up among compliant persons >80 years (estimated marginal mean 64.4 dB/MHz for the intervention group and 61.0 dB/MHz for the placebo group, p = 0.04 for difference). In conclusion, this study showed no overall effect of treatment with vitamin B12 and folic acid on BMD or QUS parameters in elderly, mildly hyperhomocysteinemic persons, but suggests a small beneficial effect on BUA in persons >80 years who were compliant in taking the supplement.


Subject(s)
Bone Density/drug effects , Folic Acid/therapeutic use , Homocysteine/blood , Osteoporosis/prevention & control , Vitamin B 12/therapeutic use , Absorptiometry, Photon , Aged , Aged, 80 and over , Calcaneus/diagnostic imaging , Dietary Supplements , Double-Blind Method , Female , Femur Neck/diagnostic imaging , Humans , Male , Osteoporosis/blood , Ultrasonography
5.
Age Ageing ; 44(1): 136-42, 2015 Jan.
Article in English | MEDLINE | ID: mdl-25038832

ABSTRACT

BACKGROUND: several studies have been pointing towards a non-linear relationship between serum 25(OH)D and cardiovascular disease. Next to vitamin D deficiency, also higher levels of 25(OH)D have been reported to be associated with increased cardiovascular risk. We aimed to investigate the nature of the relationship between serum 25(OH)D and measures of arterial stiffness and arteriosclerosis in an elderly population. DESIGN: cross-sectional. SETTING/SUBJECTS: a subgroup of the B-PROOF study was included to determine associations between serum 25(OH)D and arterial stiffness and atherosclerosis (n = 567, 57% male, age 72.6 ± 5.6 years, mean serum 25(OH)D 54.6 ± 24.1 nmol/l). METHODS: carotid intima media thickness (IMT) was assessed using ultrasonography and pulse wave velocity (PWV) was determined with applanation tonometry. Associations were tested using multivariable restricted cubic spline functions and stratified linear regression analysis. RESULTS: the associations between serum 25(OH)D and carotid IMT or PWV were non-linear. Spline functions demonstrated a difference between 25(OH)D deficient and sufficient individuals. In serum 25(OH)D sufficient participants (≥50 nmol/l; n = 287), a positive association with IMT and serum 25(OH)D was present (ß 1.24; 95%CI [0.002; 2.473]). PWV levels were slightly lower in vitamin D deficient individuals, but the association with 25(OH)D was not significant. CONCLUSION: our study demonstrates that associations of serum 25(OH)D and PWV and IMT in an elderly population are not linear. In particular from serum 25(OH)D levels of 50 nmol/l and up, there is a slight increase of IMT with increasing 25(OH)D levels.


Subject(s)
Arteriosclerosis/etiology , Vascular Stiffness , Vitamin D/analogs & derivatives , Age Factors , Aged , Aged, 80 and over , Aging/blood , Arteriosclerosis/blood , Arteriosclerosis/diagnosis , Arteriosclerosis/physiopathology , Biomarkers/blood , Carotid Intima-Media Thickness , Cross-Sectional Studies , Female , Humans , Linear Models , Male , Manometry , Multivariate Analysis , Nonlinear Dynamics , Pulse Wave Analysis , Risk Factors , Vitamin D/blood
6.
BMC Geriatr ; 11: 80, 2011 Dec 02.
Article in English | MEDLINE | ID: mdl-22136481

ABSTRACT

BACKGROUND: Osteoporosis is a major health problem, and the economic burden is expected to rise due to an increase in life expectancy throughout the world. Current observational evidence suggests that an elevated homocysteine concentration and poor vitamin B12 and folate status are associated with an increased fracture risk. As vitamin B12 and folate intake and status play a large role in homocysteine metabolism, it is hypothesized that supplementation with these B-vitamins will reduce fracture incidence in elderly people with an elevated homocysteine concentration. METHODS/DESIGN: The B-PROOF (B-Vitamins for the PRevention Of Osteoporotic Fractures) study is a randomized double-blind placebo-controlled trial. The intervention comprises a period of two years, and includes 2919 subjects, aged 65 years and older, independently living or institutionalized, with an elevated homocysteine concentration (≥ 12 µmol/L). One group receives daily a tablet with 500 µg vitamin B12 and 400 µg folic acid and the other group receives a placebo tablet. In both tablets 15 µg (600 IU) vitamin D is included. The primary outcome of the study is osteoporotic fractures. Measurements are performed at baseline and after two years and cover bone health i.e. bone mineral density and bone turnover markers, physical performance and physical activity including falls, nutritional intake and status, cognitive function, depression, genetics and quality of life. This large multi-center project is carried out by a consortium from the Erasmus MC (Rotterdam, the Netherlands), VUmc (Amsterdam, the Netherlands) and Wageningen University, (Wageningen, the Netherlands), the latter acting as coordinator. DISCUSSION: To our best knowledge, the B-PROOF study is the first intervention study in which the effect of vitamin B12 and folic acid supplementation on osteoporotic fractures is studied in a general elderly population. We expect the first longitudinal results of the B-PROOF intervention in the second semester of 2013. The results of this intervention will provide evidence on the efficacy of vitamin B12 and folate supplementation in the prevention of osteoporotic fractures. TRIAL REGISTRATION: The B-PROOF study is registered with the Netherlands Trial (NTR NTR1333) and with ClinicalTrials.gov (NCT00696514).


Subject(s)
Dietary Supplements , Folic Acid/therapeutic use , Fractures, Bone/prevention & control , Osteoporosis/drug therapy , Vitamin B 12/therapeutic use , Aged , Aged, 80 and over , Double-Blind Method , Female , Fractures, Bone/epidemiology , Humans , Incidence , Male , Osteoporosis/epidemiology , Treatment Outcome
7.
Am J Clin Nutr ; 109(2): 276-287, 2019 02 01.
Article in English | MEDLINE | ID: mdl-30721968

ABSTRACT

Background: Lean body mass (LM) plays an important role in mobility and metabolic function. We previously identified five loci associated with LM adjusted for fat mass in kilograms. Such an adjustment may reduce the power to identify genetic signals having an association with both lean mass and fat mass. Objectives: To determine the impact of different fat mass adjustments on genetic architecture of LM and identify additional LM loci. Methods: We performed genome-wide association analyses for whole-body LM (20 cohorts of European ancestry with n = 38,292) measured using dual-energy X-ray absorptiometry) or bioelectrical impedance analysis, adjusted for sex, age, age2, and height with or without fat mass adjustments (Model 1 no fat adjustment; Model 2 adjustment for fat mass as a percentage of body mass; Model 3 adjustment for fat mass in kilograms). Results: Seven single-nucleotide polymorphisms (SNPs) in separate loci, including one novel LM locus (TNRC6B), were successfully replicated in an additional 47,227 individuals from 29 cohorts. Based on the strengths of the associations in Model 1 vs Model 3, we divided the LM loci into those with an effect on both lean mass and fat mass in the same direction and refer to those as "sumo wrestler" loci (FTO and MC4R). In contrast, loci with an impact specifically on LM were termed "body builder" loci (VCAN and ADAMTSL3). Using existing available genome-wide association study databases, LM increasing alleles of SNPs in sumo wrestler loci were associated with an adverse metabolic profile, whereas LM increasing alleles of SNPs in "body builder" loci were associated with metabolic protection. Conclusions: In conclusion, we identified one novel LM locus (TNRC6B). Our results suggest that a genetically determined increase in lean mass might exert either harmful or protective effects on metabolic traits, depending on its relation to fat mass.


Subject(s)
Adipose Tissue/metabolism , Body Composition/genetics , Body Fluid Compartments/metabolism , Muscle, Skeletal/metabolism , Phenotype , Polymorphism, Single Nucleotide , ADAMTS Proteins/genetics , Absorptiometry, Photon , Adolescent , Adult , Aged , Aged, 80 and over , Alpha-Ketoglutarate-Dependent Dioxygenase FTO/genetics , Electric Impedance , Extracellular Matrix Proteins/genetics , Female , Genome-Wide Association Study , Humans , Male , Middle Aged , RNA-Binding Proteins/genetics , Receptor, Melanocortin, Type 4/genetics , Versicans/genetics , White People/genetics , Young Adult
8.
J Am Med Dir Assoc ; 18(1): 88.e1-88.e15, 2017 01.
Article in English | MEDLINE | ID: mdl-27889507

ABSTRACT

OBJECTIVE: To investigate whether the CYP2C9*2 and *3 variants modify benzodiazepine-related fall risk. DESIGN: Three prospective studies; the Rotterdam Study, B-PROOF, and LASA. SETTING: Community-dwelling individuals living in or near five Dutch cities. PARTICIPANTS: There were 11,485 participants aged ≥55 years. MEASUREMENTS: Fall incidents were recorded prospectively. Benzodiazepine use was determined using pharmacy dispensing records or interviews. Cox proportional hazard models adjusted for age and sex were applied to determine the association between benzodiazepine use and fall risk stratified for CYP2C9 genotype and comparing benzodiazepine users to nonusers. The results of the three studies were combined applying meta-analysis. Within benzodiazepine users, the association between genotypes and fall risk was also assessed. RESULTS: Three thousand seven hundred five participants (32%) encountered a fall during 91,996 follow-up years, and 4% to 15% (depending on the study population) used benzodiazepines. CYP2C9 variants had frequencies of 13% for the *2 allele and 6% for the *3 allele. Compared to nonusers, current benzodiazepine use was associated with an 18% to 36% increased fall risk across studies with a combined hazard ratio (HR) = 1.26 (95% confidence interval [CI], 1.13; 1.40). CYP2C9*2 or *3 allele variants modified benzodiazepine-related fall risk. Compared to nonusers, those carrying a CYP2C9*2 or *3 allele and using benzodiazepines had a 45% increased fall risk (HR, 1.45 95% CI, 1.21; 1.73), whereas CYP2C9*1 homozygotes using benzodiazepines had no increased fall risk (HR, 1.14; 95% CI, 0.90; 1.45). Within benzodiazepine users, having a CYP2C9*2 or *3 allele was associated with an increased fall risk (HR, 1.35; 95% CI, 1.06; 1.72). Additionally, we observed an allele dose effect; heterozygous allele carriers had a fall risk of (HR = 1.30; 95% CI, 1.05; 1.61), and homozygous allele carriers of (HR = 1.91 95% CI, 1.23; 2.96). CONCLUSIONS: CYP2C9*2 and *3 allele variants modify benzodiazepine-related fall risk. Those using benzodiazepines and having reduced CYP2C9 enzyme activity based on their genotype are at increased fall risk. In clinical practice, genotyping might be considered for elderly patients with an indication for benzodiazepine use. However, because the exact role of CYP2C9 in benzodiazepine metabolism is still unclear, additional research is warranted.


Subject(s)
Accidental Falls , Benzodiazepines/adverse effects , Cytochrome P-450 CYP2C9/genetics , Genotype , Aged , Aged, 80 and over , Female , Humans , Male , Netherlands , Pharmacogenetics , Proportional Hazards Models , Prospective Studies
9.
Nat Commun ; 8(1): 80, 2017 07 19.
Article in English | MEDLINE | ID: mdl-28724990

ABSTRACT

Lean body mass, consisting mostly of skeletal muscle, is important for healthy aging. We performed a genome-wide association study for whole body (20 cohorts of European ancestry with n = 38,292) and appendicular (arms and legs) lean body mass (n = 28,330) measured using dual energy X-ray absorptiometry or bioelectrical impedance analysis, adjusted for sex, age, height, and fat mass. Twenty-one single-nucleotide polymorphisms were significantly associated with lean body mass either genome wide (p < 5 × 10-8) or suggestively genome wide (p < 2.3 × 10-6). Replication in 63,475 (47,227 of European ancestry) individuals from 33 cohorts for whole body lean body mass and in 45,090 (42,360 of European ancestry) subjects from 25 cohorts for appendicular lean body mass was successful for five single-nucleotide polymorphisms in/near HSD17B11, VCAN, ADAMTSL3, IRS1, and FTO for total lean body mass and for three single-nucleotide polymorphisms in/near VCAN, ADAMTSL3, and IRS1 for appendicular lean body mass. Our findings provide new insight into the genetics of lean body mass.Lean body mass is a highly heritable trait and is associated with various health conditions. Here, Kiel and colleagues perform a meta-analysis of genome-wide association studies for whole body lean body mass and find five novel genetic loci to be significantly associated.


Subject(s)
Genome-Wide Association Study , Thinness/genetics , 17-Hydroxysteroid Dehydrogenases/genetics , ADAMTS Proteins/genetics , Aldehyde Oxidoreductases/genetics , Alpha-Ketoglutarate-Dependent Dioxygenase FTO/genetics , Body Composition , Extracellular Matrix Proteins/genetics , Humans , Insulin Receptor Substrate Proteins/genetics , Phenotype , Polymorphism, Single Nucleotide , Quantitative Trait Loci , Regulatory Elements, Transcriptional , Versicans/genetics
11.
Nutrients ; 9(1)2016 Dec 24.
Article in English | MEDLINE | ID: mdl-28029114

ABSTRACT

AIM: We investigated cross-sectional associations between circulating homocysteine, folate, biomarkers of vitamin B12 status and brain volumes. We furthermore compared brain volumes of participants who received daily folic acid and vitamin B12 supplementation with participants who did not. METHODS: Participants of the B-PROOF study (n = 2919) were assigned to 400 µg folic acid and 500 µg vitamin B12, or a placebo. After two years of intervention, T1-weighted magnetic resonance imaging (MRI) scans were made in a random subsample (n = 218) to obtain grey and white matter volume, and total brain volume (TBV). Plasma homocysteine, serum folate, vitamin B12, holotranscobalamin, and methylmalonic acid concentrations were measured. RESULTS: Multiple linear regression analyses showed inverse associations between plasma homocysteine with TBV (ß = -0.91, 95% CI -1.85-0.03; p = 0.06) and between serum folate and TBV (ß = -0.20, 95% CI -0.38, -0.02; p = 0.03). No significant associations were observed for serum vitamin B12 and holotranscobalamin. Fully adjusted ANCOVA models showed that the group that received B-vitamins had a lower TBV (adjusted mean 1064, 95% CI 1058-1069 mL) than the non-supplemented group (1072, 95% CI 1067-1078 mL, p = 0.03). CONCLUSIONS: Results were contradictory, with higher Hcy levels associated with lower TBV, but also with higher folate levels associated with lower TBV. In addition, the lack of a baseline measurement withholds us from giving recommendations on whether folic acid and vitamin B12 supplementation will be beneficial above and beyond normal dietary intake for brain health.


Subject(s)
Brain/anatomy & histology , Folic Acid/blood , Homocysteine/blood , Vitamin B 12/blood , Aged , Biomarkers/blood , Body Mass Index , Cross-Sectional Studies , Dietary Supplements , Double-Blind Method , Female , Humans , Linear Models , Magnetic Resonance Imaging , Male , Methylmalonic Acid/blood , Nutritional Status , Organ Size , Tandem Mass Spectrometry , Transcobalamins/analysis
12.
J Steroid Biochem Mol Biol ; 164: 168-176, 2016 11.
Article in English | MEDLINE | ID: mdl-26275945

ABSTRACT

BACKGROUND/OBJECTIVES: The prevalence of vitamin D deficiency among seniors is high. Whereas sun exposure, vitamin D intake, genes, demographics, and lifestyle have been identified as being important determinants of vitamin D status, the impact of these factors is expected to differ across populations. To improve current prevention and treatment strategies, this study aimed to explore the main determinants of vitamin D status and its relative importance in a population of community-dwelling Dutch older adults. METHODS/SUBJECTS: Serum 25-hydroxyvitamin D (25(OH)D) was measured in 2857 adults aged ≥65 years. Sun exposure was assessed with a structured questionnaire (n=1012), vitamin D intake using a Food Frequency Questionnaire (n=596), and data on genetic variation that may affect 25(OH)D status was obtained for 4 genes, DHCR7 (rs12785878), CYP2R1 (rs10741657), GC (rs2282679), and CYP24A1 (rs6013897) (n=2530). RESULTS: Serum 25(OH)D concentrations <50nmol/L were observed in 45% of the population; only 6% of these participants used vitamin D supplements. Sun exposure (being outside daily during summer: 66±25nmol/L vs not being outside daily during summer: 58±27nmol/L, P=0.02) and vitamin D intake (per unit µg/day during winter/spring: 3.1±0.75nmol/L, P<0.0001) were associated with higher 25(OH)D concentrations. Major allele carriers of SNPs related to DHCR7, CYP24A1, and GC, as well as CYP2R1 minor allele carriers had the highest 25(OH)D concentrations. Together, sun (R2=0.29), vitamin D intake (R2=0.24), and genes (R2=0.28) explained 35% (R2=0.35) of the variation in 25(OH)D concentrations during summer/autumn period, when adjusted for age, sex, BMI, education, alcohol consumption, smoking, physical activity, and self-rated health status (n=185). CONCLUSION: The investigated determinants explained 35% of 25(OH)D status. Of the three main determinants under study, sun exposure still appeared to be an important determinant of serum 25(OH)D in older individuals, closely followed by genes, and vitamin D intake. Given the low frequency of vitamin D supplement use in this population, promoting supplement use may be an inexpensive, easy, and effective strategy to fight vitamin D deficiency.


Subject(s)
Vitamin D Deficiency/epidemiology , Vitamin D Deficiency/genetics , Vitamin D/therapeutic use , Vitamins/therapeutic use , Aged , Aged, 80 and over , Cholestanetriol 26-Monooxygenase/genetics , Cross-Sectional Studies , Cytochrome P450 Family 2/genetics , Dietary Supplements , Female , Humans , Male , Oxidoreductases Acting on CH-CH Group Donors/genetics , Polymorphism, Single Nucleotide , Seasons , Sunlight , Vitamin D/analogs & derivatives , Vitamin D/blood , Vitamin D/genetics , Vitamin D Deficiency/blood , Vitamin D Deficiency/prevention & control , Vitamin D3 24-Hydroxylase/genetics , Vitamins/genetics
13.
Nutrients ; 8(11)2016 Nov 23.
Article in English | MEDLINE | ID: mdl-27886078

ABSTRACT

Lowering elevated plasma homocysteine (Hcy) concentrations by supplementing vitamin B12 and folic acid may reduce depressive symptoms and improve health-related quality of life (HR-QoL) in older adults. This study aimed to test this hypothesis in a randomized controlled trial. Participants (N = 2919, ≥65 years, Hcy concentrations ≥12 µmol/L) received either 500 µg vitamin B12 and 400 µg folic acid daily or placebo for two years. Both tablets contained 15 µg vitamin D3. Depressive symptoms were measured with the Geriatric Depression Scale-15 (GDS-15). HR-QoL was assessed with the SF-12 Mental and Physical component summary scores and the EQ-5D Index score and Visual Analogue Scale. Differences in two-year change scores were analyzed with Analysis of Covariance (ANCOVA). Hcy concentrations decreased more in the intervention group, but two-year change scores of the GDS-15 and three of four HR-QoL measures did not differ between groups. The EQ-5D Index score declined less in the intervention group than in the placebo group (mean change 0.00 vs. -0.02, p = 0.004). In conclusion, two-year supplementation with vitamin B12 and folic acid in older adults with hyperhomocysteinemia showed that lowering Hcy concentrations does not reduce depressive symptoms, but it may have a small positive effect on HR-QoL.


Subject(s)
Affect , Depression/prevention & control , Dietary Supplements , Folic Acid/administration & dosage , Homocysteine/blood , Hyperhomocysteinemia/drug therapy , Quality of Life , Vitamin B 12/administration & dosage , Age Factors , Aged , Biomarkers/blood , Depression/diagnosis , Depression/etiology , Depression/psychology , Double-Blind Method , Drug Combinations , Female , Humans , Hyperhomocysteinemia/blood , Hyperhomocysteinemia/diagnosis , Male , Netherlands , Psychiatric Status Rating Scales , Risk Factors , Time Factors , Treatment Outcome , Up-Regulation
14.
J Hypertens ; 33(9): 1897-906; discussion 1906, 2015 Sep.
Article in English | MEDLINE | ID: mdl-26147383

ABSTRACT

INTRODUCTION: Hyperhomocysteinemia is an important cardiovascular risk indicator in the oldest old, and is associated with elevated arterial stiffness in this age group. Since several intervention trials reported a lack of benefit of B-vitamin supplementation on cardiovascular outcomes, we aimed to investigate the effect of B-vitamin supplementation on arterial stiffness and atherosclerosis in hyperhomocysteinemic elderly patients. METHODS: The B-PROOF study is a double-blind, randomized controlled trial, including 2919 elderly aged at least 65 years, with hyperhomocysteinemia (12-50  µmol/l), treated with B-vitamins (500  µg vitamin B12 and 400  µg folic acid) or placebo for 2 years. In a subgroup (n = 569), the effect of B-vitamins on pulse wave velocity (PWV) was investigated as a measurement of arterial stiffness. To measure atherosclerosis, carotid intima-media thickness (IMT) measures had been used. Incidents of cardiovascular and cerebrovascular events were determined via structured questionnaires, and blood pressure was also measured. RESULTS: Compared to placebo, B-vitamin supplementation lowered serum homocysteine by 3.6  µmol/l (P < 0.001). Analysis of covariance showed no effect of supplementation on PWV levels, and this was not different for patients without increased arterial stiffness at baseline. Furthermore, no effect on carotid IMT was observed. DISCUSSION: Vitamin B12 and folic acid supplementation in hyperhomocysteinemic elderly patients have no effect on PWV or carotid IMT. Further research will still be necessary to unravel the effects and pathways of homocysteine-lowering treatment on cardiovascular outcomes.


Subject(s)
Atherosclerosis/physiopathology , Blood Pressure/drug effects , Cardiovascular Diseases/physiopathology , Dietary Supplements , Folic Acid/administration & dosage , Hyperhomocysteinemia/physiopathology , Vascular Stiffness/drug effects , Vitamin B 12/administration & dosage , Aged , Aged, 80 and over , Atherosclerosis/mortality , Blood Pressure/physiology , Cardiovascular Diseases/mortality , Carotid Intima-Media Thickness , Double-Blind Method , Female , Humans , Hyperhomocysteinemia/mortality , Male , Pulse Wave Analysis , Risk Factors , Treatment Outcome , Vascular Stiffness/physiology
15.
J Am Med Dir Assoc ; 16(7): 621-7, 2015 Jul 01.
Article in English | MEDLINE | ID: mdl-25838206

ABSTRACT

OBJECTIVES: First, the association between serum 25-hydroxyvitamin D (25[OH]D) and cognitive performance was examined. Second, we assessed whether there was evidence for an interplay between 25(OH)D and glucose homeostasis in the association with cognitive performance. DESIGN, SETTING, AND PARTICIPANTS: Associations were studied using cross-sectional data of 776 (3 domains) up to 2722 (1 domain) Dutch community-dwelling older adults, aged 65 years or older. MEASUREMENTS: Serum 25(OH)D, plasma glucose, and insulin concentrations were obtained. Cognitive performance was assessed with an extensive cognitive test battery. Prevalence ratios (PRs) were calculated to quantify the association between 25(OH)D and cognition; poor performance was defined as the worst 10% of the distribution of the cognitive scores. RESULTS: The overall median MMSE score was 29 (IQR 28-30). Higher serum 25(OH)D was associated with better attention and working memory, PR 0.50 (95% CI 0.29-0.84) for the third serum 25(OH)D tertile, indicating a 50% lower probability of being a poor performer than participants in the lowest tertile. Beneficial trends were shown for 25(OH)D with executive function and episodic memory. Serum 25(OH)D was not associated with plasma glucose or insulin. Plasma insulin only modified the association between serum 25(OH)D and executive function (P for interaction: .001), suggesting that the improvement in executive function with high 25(OH)D concentrations is stronger in participants with high plasma insulin concentrations compared with those with low plasma insulin concentrations. CONCLUSION: Higher 25(OH)D concentrations significantly associated with better attention and working memory performance. This study does not demonstrate an interplay between serum 25(OH)D and glucose homeostasis in the association with cognitive performance.


Subject(s)
Blood Glucose , Executive Function/physiology , Homeostasis , Vitamin D/analogs & derivatives , Aged , Aged, 80 and over , Cross-Sectional Studies , Female , Homes for the Aged , Humans , Insulin/blood , Male , Netherlands , Vitamin D/blood
16.
Am J Clin Nutr ; 100(6): 1578-86, 2014 Dec.
Article in English | MEDLINE | ID: mdl-25411293

ABSTRACT

BACKGROUND: Elevated plasma homocysteine concentrations are a risk factor for osteoporotic fractures. Lowering homocysteine with combined vitamin B-12 and folic acid supplementation may reduce fracture risk. OBJECTIVE: This study [B-vitamins for the PRevention Of Osteoporotic Fractures (B-PROOF)] aimed to determine whether vitamin B-12 and folic acid supplementation reduces osteoporotic fracture incidence in hyperhomocysteinemic elderly individuals. DESIGN: This was a double-blind, randomized, placebo-controlled trial in 2919 participants aged ≥65 y with elevated homocysteine concentrations (12-50 µmol/L). Participants were assigned to receive daily 500 µg vitamin B-12 plus 400 µg folic acid or placebo supplementation for 2 y. Both intervention and placebo tablets also contained 600 IU vitamin D3. The primary endpoint was time to first osteoporotic fracture. Exploratory prespecified subgroup analyses were performed in men and women and in individuals younger than and older than age 80 y. Data were analyzed according to intention-to-treat and per-protocol principles. RESULTS: Osteoporotic fractures occurred in 61 persons (4.2%) in the intervention group and 75 persons (5.1%) in the placebo group. Osteoporotic fracture risk was not significantly different between groups in the intention-to-treat analyses (HR: 0.84; 95% CI: 0.58, 1.21) or per-protocol analyses (HR: 0.81; 95% CI: 0.54, 1.21). For persons aged >80 y, in per-protocol analyses, osteoporotic fracture risk was lower in the intervention group than in the placebo group (HR: 0.27; 95% CI: 0.10, 0.74). The total number of adverse events (including mortality) did not differ between groups. However, 63 and 42 participants in the intervention and placebo groups, respectively, reported incident cancer (HR: 1.56; 95% CI: 1.04, 2.31). CONCLUSIONS: These data show that combined vitamin B-12 and folic acid supplementation had no effect on osteoporotic fracture incidence in this elderly population. Exploratory subgroup analyses suggest a beneficial effect on osteoporotic fracture prevention in compliant persons aged >80 y. However, treatment was also associated with increased incidence of cancer, although the study was not designed for assessing cancer outcomes. Therefore, vitamin B-12 plus folic acid supplementation cannot be recommended at present for fracture prevention in elderly people. The B-PROOF study was registered with the Netherlands Trial Register (trialregister.nl) as NTR1333 and at clinicaltrials.gov as NCT00696414.


Subject(s)
Dietary Supplements , Folic Acid/administration & dosage , Homocysteine/blood , Osteoporotic Fractures/epidemiology , Osteoporotic Fractures/prevention & control , Vitamin B 12/administration & dosage , Aged , Aged, 80 and over , Dose-Response Relationship, Drug , Double-Blind Method , Endpoint Determination , Female , Follow-Up Studies , Humans , Hyperhomocysteinemia/blood , Hyperhomocysteinemia/drug therapy , Incidence , Male , Motor Activity , Netherlands , Risk Factors , Treatment Outcome
17.
Neurology ; 83(23): 2158-66, 2014 Dec 02.
Article in English | MEDLINE | ID: mdl-25391305

ABSTRACT

OBJECTIVE: We investigated the effects of 2-year folic acid and vitamin B12 supplementation on cognitive performance in elderly people with elevated homocysteine (Hcy) levels. METHODS: This multicenter, double-blind, randomized, placebo-controlled trial included 2,919 elderly participants (65 years and older) with Hcy levels between 12 and 50 µmol/L. Participants received daily either a tablet with 400 µg folic acid and 500 µg vitamin B12 (B-vitamin group) or a placebo tablet. Both tablets contained 15 µg vitamin D3. Data were available for global cognitive functioning assessed by Mini-Mental State Examination (n = 2,556), episodic memory (n = 2,467), attention and working memory (n = 759), information processing speed (n = 731), and executive function (n = 721). RESULTS: Mean age was 74.1 (SD 6.5) years. Hcy concentrations decreased 5.0 (95% confidence interval -5.3 to -4.7) µmol/L in the B-vitamin group and 1.3 (-1.6 to -0.9) µmol/L in the placebo group. Cognitive domain scores did not differ over time between the 2 groups, as determined by analysis of covariance. Mini-Mental State Examination score decreased with 0.1 (-0.2 to 0.0) in the B-vitamin group and 0.3 (-0.4 to -0.2) in the placebo group (p = 0.05), as determined by an independent t test. CONCLUSIONS: Two-year folic acid and vitamin B12 supplementation did not beneficially affect performance on 4 cognitive domains in elderly people with elevated Hcy levels. It may slightly slow the rate of decline of global cognition, but the reported small difference may be attributable to chance. CLASSIFICATION OF EVIDENCE: This study provides Class I evidence that 2-year supplementation with folic acid and vitamin B12 in hyperhomocysteinemic elderly people does not affect cognitive performance.


Subject(s)
Cognition Disorders/drug therapy , Cognition/drug effects , Folic Acid/therapeutic use , Memory/drug effects , Vitamin B 12/therapeutic use , Aged , Aged, 80 and over , Dietary Supplements , Double-Blind Method , Executive Function/physiology , Female , Humans , Male , Neuropsychological Tests , Vitamin B 12/administration & dosage
18.
Drugs Aging ; 31(12): 917-27, 2014 Dec.
Article in English | MEDLINE | ID: mdl-25398701

ABSTRACT

BACKGROUND: Medication use is a potentially modifiable risk factor for falling; psychotropic and cardiovascular drugs have been indicated as main drug groups that increase fall risk. However, evidence is mainly based on studies that recorded falls retrospectively and/or did not determine medication use at the time of the fall. Therefore, we investigated the associations indicated in the literature between medication use and falls, using prospectively recorded falls and medication use determined at the time of the fall. METHODS: Data from the B-PROOF (B-vitamins for the prevention of osteoporotic fractures) study were used, concerning community-dwelling elderly aged ≥65 years. We included 2,407 participants with pharmacy dispensing records. During the 2- to 3-year follow-up, participants recorded falls using a fall calendar. Cox proportional hazard models were applied, adjusting for potential confounders including age, sex, health status variables and concomitant medication use. RESULTS: During follow-up, 1,147 participants experienced at least one fall. Users of anti-arrhythmic medication had an increased fall risk (hazard ratio [HR] 1.61; 95% confidence interval [CI] 1.12-2.32) compared with non-users. Similarly, non-selective beta-blocker use was associated with an increased fall risk (HR 1.41 [95% CI 1.12-1.78]), while statin use was associated with a lower risk (HR 0.81 [95% CI 0.71-0.94]). Benzodiazepine use (HR 1.32 [95% CI 1.02-1.71]), and antidepressant use (HR 1.40 [95% CI 1.07-1.82]) were associated with an increased fall risk. Use of other cardiovascular and psychotropic medication was not associated with fall risk. CONCLUSION: Our results strengthen the evidence for an increased fall risk in community-dwelling elderly during the use of anti-arrhythmics, non-selective beta-blockers, benzodiazepines, and antidepressant medication. Clinicians should prescribe these drugs cautiously and if possible choose safer alternatives for older patients.


Subject(s)
Accidental Falls/statistics & numerical data , Accidental Falls/prevention & control , Aged , Aged, 80 and over , Anti-Arrhythmia Agents/adverse effects , Benzodiazepines/adverse effects , Female , Health Services for the Aged , Hip Fractures/epidemiology , Hip Fractures/prevention & control , Humans , Incidence , Independent Living , Male , Netherlands/epidemiology , Proportional Hazards Models , Prospective Studies , Randomized Controlled Trials as Topic
19.
Drugs Aging ; 31(8): 611-21, 2014 Aug.
Article in English | MEDLINE | ID: mdl-24993981

ABSTRACT

BACKGROUND: Elevated homocysteine levels are a risk indicator for cardiovascular disease, fractures and cognitive decline. Previous studies indicated associations between homocysteine levels and medication use, including antihypertensive, lipid-lowering and antidiabetic medication. However, results were often contradictory and inconclusive. Our objective was to study the associations established previously in more detail by sub-classifying medication groups, and investigate the potential mediating role of vitamin B12 and folate status. MATERIALS AND METHODS: Baseline data from the B-PROOF (B-vitamins for the PRevention Of Osteoporotic Fractures) study were used. We included 2,912 participants aged ≥65 years, with homocysteine levels of 12-50 µmol/L and creatinine levels ≤150 µmol/L, for whom self-reported medication data were available. We used multivariable linear regression models and analysis of covariance to assess the association between medication use and plasma homocysteine levels, and the potential mediation by serum vitamin B12 and folate. RESULTS: The mean age was 74 years (standard deviation, 6.5), 50 % were women, and median homocysteine levels were 14 µmol/L [interquartile range, 13-17 µmol/L]. Higher mean homocysteine levels were observed in users vs. non-users for diuretics (15.2 vs. 14.9, p = 0.043), high-ceiling sulphonamide diuretics (16.0 vs. 14.9, p < 0.001), medication acting via the renin-angiotensin system (15.2 vs. 14.9, p = 0.029) and metformin (15.6 vs. 15.1, p = 0.006). Non-selective ß-blocker use was associated with lower mean homocysteine levels (14.4 vs. 15.0, p = 0.019). Only this association was mediated by an underlying association with vitamin B12 and folate levels. CONCLUSION: The associations between homocysteine levels and medication use appear to be fairly modest. Our results suggest that medication use is unlikely to contribute to clinically relevant changes in plasma homocysteine levels.


Subject(s)
Homocysteine/blood , Vitamin B 12 Deficiency/blood , Aged , Diuretics/administration & dosage , Female , Folic Acid/administration & dosage , Health Services for the Aged , Humans , Male , Metformin/administration & dosage , Netherlands , Osteoporosis/epidemiology , Population Surveillance , Vitamin B 12/administration & dosage
20.
Blood Press Monit ; 18(6): 332-8, 2013 Dec.
Article in English | MEDLINE | ID: mdl-24192847

ABSTRACT

OBJECTIVE: Indices of arterial stiffness and aortic pressure are usually assessed by applanation tonometry. The more recently introduced oscillometric device is simpler to use. Several studies have investigated the agreement between these two devices, but not in populations with elevated levels of arterial stiffness. Therefore, we evaluated the agreement in an elderly population with high risk of arterial stiffness. PATIENTS AND METHODS: We included a subgroup of the B-PROOF study (n=344, mean age 73 years, 60% men), whose aortic pulse wave velocity (aPWV), aortic augmentation index (AIx), aortic pulse pressure (PP), and aortic systolic blood pressure (SBP) were assessed both with applanation tonometry (SphygmoCor) and with oscillometry (Arteriograph). We investigated agreement between the two devices using Pearson correlations and Bland-Altman analysis. We carried out a stratified analysis in participants with more pronounced arterial stiffness (SphygmoCor aPWV>12 m/s). RESULTS: The oscillometric method produced higher values of AIx, aortic PP, and aortic SBP (P<0.01) than applanation tonometry. aPWV values were lower (P<0.01) and were not correlated (r=-0.06, P=0.92), whereas AIx measurements (r=0.35 P<0.01), aortic PP (r=0.57 P<0.01), and aortic SBP (r=0.68 P<0.01) measurements were correlated. Bland-Altman analysis showed insufficient agreement between the two devices, especially in those with elevated levels of arterial stiffness (aPWV>12 m/s). CONCLUSION: Particularly in the elderly with elevated levels of arterial stiffness, measurements of aPWV obtained with oscillometry and applanation tonometry show poor agreement. Also, AIx, aortic SBP, and aortic PP show clearly less than optimal agreement.


Subject(s)
Cardiovascular Diseases/diagnosis , Manometry/methods , Oscillometry/methods , Pulse Wave Analysis , Vascular Stiffness/physiology , Aged , Aged, 80 and over , Aorta/physiopathology , Blood Pressure , Blood Pressure Determination/methods , Female , Humans , Male , Risk Factors
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