Large-scale circulating proteome association study (CPAS) meta-analysis identifies circulating proteins and pathways predicting incident hip fractures

Hip fractures are associated with significant disability, high cost, and mortality. However, the exact biological mechanisms underlying susceptibility to hip fractures remain incompletely understood. In an exploratory search of the underlying biology as reflected through the circulating proteome, we performed a comprehensive Circulating Proteome Association Study (CPAS) meta-analysis for incident hip fractures. Analyses included 6430 subjects from two prospective cohort studies (Cardiovascular Health Study and Trøndelag Health Study) with circulating proteomics data (aptamer-based 5 K SomaScan version 4.0 assay; 4979 aptamers). Associations between circulating protein levels and incident hip fractures were estimated for each cohort using age and sex-adjusted Cox regression models. Participants experienced 643 incident hip fractures. Compared with the individual studies, inverse-variance weighted meta-analyses yielded more statistically significant associations, identifying 23 aptamers associated with incident hip fractures (conservative Bonferroni correction 0.05/4979, P < 1.0 × 10-5). The aptamers most strongly associated with hip fracture risk corresponded to two proteins of the growth hormone/insulin growth factor system (GHR and IGFBP2), as well as GDF15 and EGFR. High levels of several inflammation-related proteins (CD14, CXCL12, MMP12, ITIH3) were also associated with increased hip fracture risk. Ingenuity pathway analysis identified reduced LXR/RXR activation and increased acute phase response signaling to be overrepresented among those proteins associated with increased hip fracture risk. These analyses identified several circulating proteins and pathways consistently associated with incident hip fractures. These findings underscore the usefulness of the meta-analytic approach for comprehensive CPAS in a similar manner as has previously been observed for large-scale human genetic studies. Future studies should investigate the underlying biology of these potential novel drug targets.

Albuminuria: An Underappreciated Risk Factor for Cardiovascular Disease

Albuminuria, an established biomarker of the progression of chronic kidney disease, is also recognized as a biomarker for the risk of cardiovascular disease. Elevated urinary albumin excretion indicates kidney damage and systemic vascular disease, including myocardial capillary disease and arterial stiffness. Albuminuria is associated with an increased risk of coronary artery disease, stroke, heart failure, arrhythmias, and microvascular disease. There are now several therapeutic agents that can lead to albuminuria lowering and a reduction in cardiovascular risk. However, screening for albuminuria is still low. Considering the importance of multidisciplinary management of patients with cardiovascular disease, it is crucial that health care professionals managing such patients are aware of the benefits of albuminuria surveillance and management.

Albuminuria Screening in People With Type 2 Diabetes in a Managed Care Organization

Introduction

Albuminuria-an increased amount of urine albumin, in milligrams, adjusted for grams of urine creatinine-is an early marker of diabetic kidney disease. Several new classes of medications are now available that effectively lower albuminuria levels with the potential to delay or prevent the progression of diabetic kidney disease. However, screening for albuminuria in the U.S. is low in population-based studies (<10% to ∼50% at most). In this study, we examine whether screening for albuminuria was improved in an integrated model of healthcare delivery following the recommendations of the National Committee for Quality Assurance mandate (an umbrella group for the managed healthcare industry) to screen for albuminuria.

Methods

We examined screening for albuminuria over a 2-year period among people with Type 2 diabetes in a U.S. HMO with an electronic medical record, onto which automated laboratory ordering for albuminuria could be added when a patient appeared at the laboratory (for any reason) if albuminuria testing had not been obtained within the previous 365 days. Participants under this plan received diabetes education at no cost and panel managers to guide their diabetes care. Logistic regression using data from 2020 and 2021, separately, evaluated the relationship between patient characteristics and the likelihood of albuminuria screening.

Results

There were 20,688 and 22,487 participants with Type 2 diabetes mellitus in 2020 and 2021, respectively, who were analyzed. Approximately 80% were screened for albuminuria in both years. African American participants and those aged >64 years were more likely to have completed albuminuria screening. Screened individuals had lower HbA1c, blood pressure, and low-density lipoprotein cholesterol levels than those who were not screened.

Conclusions

In an integrated healthcare model, it is possible to achieve consistently high rates of albuminuria screening in people with Type 2 diabetes, especially in groups at high risk for kidney disease.

Association of Immune Cell Subsets with Incident Hip Fracture: The Cardiovascular Health Study

In this study, we aimed to evaluate the association of innate and adaptive immune cell subsets in peripheral blood mononuclear cells (PBMCs) with hip fracture. To conduct this study, we used data from the Cardiovascular Health Study (CHS), a U.S. multicenter observational cohort of community-dwelling men and women aged ≥ 65 years. Twenty-five immune cell phenotypes were measured by flow cytometry from cryopreserved PBMCs of CHS participants collected in 1998-1999. The natural killer (NK), γδ T, T helper 17 (Th17), and differentiated/senescent CD4+CD28- T cell subsets were pre-specified as primary subsets of interest. Hip fracture incidence was assessed prospectively by review of hospitalization records. Multivariable Cox hazard models evaluated associations of immune cell phenotypes with incident hip fracture in sex-stratified and combined analyses. Among 1928 persons, 259 hip fractures occurred over a median 9.7 years of follow-up. In women, NK cells were inversely associated with hip fracture [hazard ratio (HR) 0.77, 95% confidence interval (CI) 0.60-0.99 per one standard deviation higher value] and Th17 cells were positively associated with hip fracture [HR 1.18, 95% CI 1.01-1.39]. In men, γδ T cells were inversely associated with hip fracture [HR 0.60, 95% CI 0.37-0.98]. None of the measured immune cell phenotypes were significantly associated with hip fracture incidence in combined analyses. In this large prospective cohort of older adults, potentially important sex differences in the associations of immune cell phenotypes and hip fracture were identified. However, immune cell phenotypes had no association with hip fracture in analyses combining men and women.

Dexamethasone Suppression Testing in a Contemporary Cohort with Adrenal Incidentalomas in Two U.S. Integrated Healthcare Systems

Autonomous cortisol secretion (ACS) from an adrenal adenoma can increase the risk for comorbidities and mortality. The dexamethasone suppression test (DST) is the standard method to diagnose ACS. A multi-site, retrospective cohort of adults with diagnosed adrenal tumors was used to understand patient characteristics associated with DST completion and ACS. Time to DST completion was defined using the lab value and result date; follow-up time was from the adrenal adenoma diagnosis to the time of completion or censoring. ACS was defined by a DST > 1.8 µg/dL (50 nmol/L). The Cox proportional hazards regression model assessed associations between DST completion and patient characteristics. In patients completing a DST, a logistic regression model evaluated relationships between elevated ACS and covariates. We included 24,259 adults, with a mean age of 63.1 years, 48.1% obese, and 28.7% with a Charlson comorbidity index ≥ 4. Approximately 7% (n = 1768) completed a DST with a completion rate of 2.36 (95% CI 2.35, 2.37) per 100 person-years. Fully adjusted models reported that male sex and an increased Charlson comorbidity index were associated with a lower likelihood of DST completion. Current or former smoking status and an increased Charlson comorbidity index had higher odds of a DST > 1.8 μg/dL. In conclusion, clinical policies are needed to improve DST completion and the management of adrenal adenomas.

Plasma Levels of Branched Chain Amino Acids, Incident Hip Fractures, and Bone Mineral Density of the Hip and Spine

OBJECTIVE

Branched chain amino acids (BCAA) are building blocks for protein, an essential component of bone. However, the association of plasma levels of BCAA with fractures in populations outside of Hong Kong or with hip fractures in particular is not known. The purpose of these analyses was to determine the relationship of BCAA including valine, leucine, and isoleucine and total BCAA (SD of the sum of Z-scores for each BCAA) with incident hip fractures and bone mineral density (BMD) of the hip and lumbar spine in older African American and Caucasian men and women in the Cardiovascular Health Study.

DESIGN

Longitudinal analyses of association of plasma levels of BCAA with incident hip fractures and cross-sectional BMD of the hip and lumbar spine from the Cardiovascular Health Study.

SETTING

Community.

PARTICIPANTS

A total of 1850 men (38% of cohort) and women; mean age 73 years.

MAIN OUTCOME MEASURES

Incident hip fractures and cross-sectional BMD of the total hip, femoral neck, and lumbar spine.

RESULTS

In fully adjusted models, over 12 years of follow-up, we observed no significant association between incident hip fracture and plasma values of valine, leucine, isoleucine, or total BCAA per 1 SD higher of each BCAA. Plasma values of leucine but not valine, isoleucine, or total BCAA, were positively and significantly associated with BMD of the total hip (P = .03) and femoral neck (P = .02), but not the lumbar spine (P = .07).

CONCLUSIONS

Plasma levels of the BCAA leucine may be associated with higher BMD in older men and women. However, given the lack of significant association with hip fracture risk, further information is needed to determine whether BCAAs would be novel targets for osteoporosis therapies.

The Association of Tryptophan and Its Metabolites With Incident Hip Fractures, Mortality, and Prevalent Frailty in Older Adults: The Cardiovascular Health Study

Amino acids are the building blocks of proteins, and sufficient protein intake is important for skeletal health. We utilized stored serum from the Cardiovascular Health Study in 1992-1993 to examine the relationship between levels of the essential amino acid tryptophan (trp) and its oxidized and nonoxidized metabolites to risk for incident hip fractures and mortality over 12 years of follow-up. We included 131 persons who sustained a hip fracture during this time period and 131 without a hip fracture over these same 12 years of follow-up; 58% female and 95% White. Weighted multivariable Cox hazards models were used to estimate the hazard ratios (HR) and 95% confidence intervals (CI) of incident hip fracture associated with a one standard deviation (SD) higher trp or its metabolites exposure. Relative risk regression was used to evaluate the cross-sectional association of trp and its metabolites with frailty. Higher serum levels of trp were significantly associated with lower risk of incident hip fractures (HR = 0.75 per SD of trp (95% CI 0.57-0.99) but were not significantly associated with mortality or frailty status by Freid's frailty index. There were no statistically significant associations between any of the oxidized or nonoxidized products of trp with incident hip fractures (p ≥ 0.64), mortality (p ≥ 0.20), or cross-sectional frailty status (p ≥ 0.13) after multiple testing adjustment. Randomized clinical trials examining whether increasing trp intake is beneficial for osteoporosis are needed. © 2023 The Authors. JBMR Plus published by Wiley Periodicals LLC on behalf of American Society for Bone and Mineral Research. This article has been contributed to by U.S. Government employees and their work is in the public domain in the USA.

Mortality Following Hip Fracture in Older Adults With and Without Coronary Heart Disease

BACKGROUND

Comorbidities like coronary heart disease are common among older people who sustain an osteoporotic hip fracture. However, their impact on short- and long-term mortality post-hip fracture is not well quantified.

METHODS

We examined 4092 and 1173 older adults without and with prevalent coronary heart disease, respectively. Post-hip fracture mortality rates were computed with Poisson models and hazard ratios with Cox regression. For perspective, we compared mortality rates among participants with prevalent coronary heart disease who had either a hip fracture or incident heart failure (but no hip fracture).

RESULTS

Among participants without prevalent coronary heart disease, the mortality rate post-hip fracture was 21.83 per 100 participant years, including 49.27 per 100 participant years in the first 6 months following hip fracture. Among participants with prevalent coronary heart disease, the corresponding mortality rates were 32.52 and 79.44 per 100 participant years, respectively. Participants with prevalent coronary heart disease and incident heart failure (but no hip fracture) had corresponding post-incident heart failure mortality rates per 100 participant years of 25.62 overall and 46.4 in the first 6 months. In all 3 groups, the hazard ratio for mortality was similarly elevated: 5- to 7-fold at 6 months and 1.7- to 2.5-fold beyond 5 years.

CONCLUSION

As a case study in the absolute effects of a comorbidity on post-hip fracture mortality, hip fracture in a person with coronary heart disease carries an exceedingly high mortality rate, even higher than that following incident heart failure in individuals with coronary heart disease.

Erratum. The Association of Measures of Cardiovascular Autonomic Function, Heart Rate, and Orthostatic Hypotension With Incident Glucose Disorders: The Cardiovascular Health Study. Diabetes Care 2022;45:2376-2382

In Table 3 of the article cited above, the β (95% CI) and P value data were incorrect due to a calculation error. The revised data do not identify specific associations of measures of autonomic function with fasting measures of insulin resistance or insulin secretion available in the Cardiovascular Health Study (CHS). However, the main outcome of the article-that certain measures of cardiac autonomic function are prospectively associated with fasting glucose level changes-remains unaffected. The authors apologize for the error. The online version of the article (https://doi.org/10.2337/dc22-0553) has been updated with the corrected data.

Age-Related Factors Associated with Hip Fracture Risk

OBJECTIVES

Advancing age is a powerful risk factor for hip fracture. The biological mechanisms through which aging impacts hip fracture risk have not been well studied.

METHODS

Biological factors associated with "advancing age" that help to explain how aging is associated with hip fracture risk are reviewed. The findings are based on analyses of the Cardiovascular Health Study, an ongoing observational study of adults ages >65 years with 25 years of follow up.

RESULTS

Five age-related factors were found to be significantly associated with hip fracture risk: (1) microvascular disease of the kidney (albuminuria and / or elevated urine albumin to creatinine ratio) and of the brain (abnormal white matter disease on brain MRI); (2) increased serum levels of carboxymethyl-lysine (CML), an advanced glycation end-product that reflects glycation and oxidative stress; (3) reduced parasympathetic tone, as derived from 24-hour Holter monitoring; (4) carotid artery atherosclerosis in the absence of clinical cardiovascular disease; and (5) increased trans-fatty acid levels in the blood. Each of these factors was associated with a 10-25%. increased risk of fracture. These associations were independent of traditional risk factors for hip fracture.

CONCLUSION

Several factors associated with older age help to explain how "aging" may be associated with hip fracture risk. These same factors may also explain the high risk for mortality following hip fracture.

The associations of markers of endothelial dysfunction with hip fracture risk

Endothelial dysfunction underlies the development of atherosclerotic vascular disease, which in turn is associated with osteoporotic fractures. Here, we examined the association of two markers of endothelial dysfunction with incident hip fracture risk in older adults but found no statistically significant associations between them.

PURPOSE/INTRODUCTION

Endothelial dysfunction underlies the development of atherosclerotic vascular disease. Vascular disease, in turn, is associated with the risk of osteoporotic fractures, such as hip fractures. Here, we examine whether two measures of endothelial dysfunction are related to hip fracture risk.

METHODS

Participants for this study were 2792 individuals (mean age 78.6 years) who had flow-mediated dilation (FMD) measured after ischemia in the forearm and 2255 adults (mean age 73.3 years) with measured soluble intercellular adhesion molecule (siCAM) levels, a constitutive endothelial cell membrane protein associated with the initiation of atherosclerosis. Mean follow-up was 9.7 and 11.7 years, respectively. There were 375 and 265 incident hip fractures, respectively, in each group.

RESULTS

In Cox proportional hazards models, there was no significant association between FMD response and incident hip fracture (HR per 1% higher FMD was 0.98 [0.93, 1.04]; p = 0.44). In exploratory analyses, when data were examined dichotomously, participants in the lowest 80% of FMD (≤ 4.5%) had an adjusted 1.29 (0.98, 1.68; p = 0.067) higher hazard of hip fracture compared to participants in the upper 20% of FMD change. There were no significant associations between siCAM and incident hip fracture whether examined as a continuous or dichotomized variable.

CONCLUSIONS

Among older adults, two measures of endothelial dysfunction were not significantly associated with hip fracture risk. There was a trend for higher fracture risk with lower FMD.

Association of covert brain infarcts and white matter hyperintensities with risk of hip fracture in older adults: the Cardiovascular Health Study

Covert brain infarcts and white matter hyperintensities (WMHs), incidental markers of brain microvascular disease commonly seen on brain MRIs in older adults, have been associated with falls and lower bone mineral density. We found covert infarcts and WMHs may also be associated with an increased risk of future hip fracture.

INTRODUCTION

To determine whether covert infarcts and white matter hyperintensities (WMHs) are associated with increased risk of incident hip fracture.

METHODS

A prospective cohort of 3373 community-dwelling adults aged ≥ 65 years enrolled in the Cardiovascular Health Study with a brain MRI (1992-1993) was analyzed. Covert infarcts were categorized by number of infarcts and largest infarct size. WMH burden was assessed by radiologists and graded qualitatively from 0 (no WMHs) to 9 (extensive).

RESULTS

Participants had 465 incident hip fractures during a mean follow-up of 12.8 years. The demographic-adjusted hazard of incident hip fracture was 32% higher among participants with ≥ 1 covert infarct compared to those without infarcts (hazard ratio (HR) 1.32; 95% CI, 1.08-1.62). The hazard of incident hip fracture was similar after further adjustment for medications and medical history (HR = 1.34; 95% CI, 1.08-1.65), but attenuated following additional adjustment for functional status, frailty, and falls (HR = 1.25; 95% CI, 0.99-1.57). Fully adjusted hazard of incident hip fracture per increase in infarct number was 1.10 (95% CI, 0.98-1.23); risk in individuals whose largest infarct was ≥ 20 mm versus 3 to < 20 mm was similar. Compared with WMH grades 0-1, the demographic-adjusted hazard of hip fracture was 1.34 (95% CI, 1.09-1.66) and 1.83 (95% CI, 1.37-2.46), respectively, for WMH grades 2-3 and 4-9. The hazard was similar following adjustment for medications and medical history (grades 2-3: HR = 1.32; 95% CI, 1.05-1.64; grades 4-9: HR = 1.69; 95% CI, 1.23-2.30), but attenuated following additional adjustment for functional status, frailty, and falls (grades 2-3: HR = 1.24; 95% CI, 0.98-1.56; grades 4-9: HR = 1.34; 95% CI, 0.95-1.90).

CONCLUSION

Older, community-dwelling adults with covert infarcts or WMHs may be at increased risk of hip fracture.

The Association of Measures of Cardiovascular Autonomic Function, Heart Rate, and Orthostatic Hypotension With Incident Glucose Disorders: The Cardiovascular Health Study

OBJECTIVE

The autonomic nervous system (ANS) innervates pancreatic endocrine cells, muscle, and liver, all of which participate in glucose metabolism. We tested whether measures of cardiovascular ANS function are independently associated with incident diabetes and annual change in fasting glucose (FG) levels as well as with insulin secretion and insulin sensitivity in older adults without diabetes.

RESEARCH DESIGN AND METHODS

Heart rate (HR) and measures of HR variability (HRV) were derived from 24-h electrocardiographic monitoring. Blood pressure, seated and standing, was measured. Cox proportional hazards models and linear mixed models were used to analyze the associations between HRV, HR, and orthostatic hypotension (SBP >20 mmHg decline) and incident diabetes or longitudinal FG change.

RESULTS

The mean annual unadjusted FG change was 1 mg/dL. Higher detrended fluctuation analyses (DFA) values, averaged over 4-11 (DFA1) or 12-20 beats (DFA2)-reflecting greater versus less organization of beat-to-beat intervals-were associated with less FG increase over time (per 1-SD increment: DFA1: -0.49 mg/dL/year [-0.96, -0.03]; DFA2: -0.55 mg/dL/year [-1.02, -0.09]). In mutually adjusted analyses, higher SD of the N-N interval (SDNN) was associated with less FG increase over time (per 1-SD increment: SDNN: -0.62 mg/dL/year [-1.22, -0.03]). Higher values of DFA1, DFA2, and SDNN were each associated with greater insulin secretion and insulin sensitivity but not with incident diabetes. We observed no association of HR or orthostatic hypotension with diabetes or FG change.

CONCLUSIONS

Specific measures of cardiac autonomic function are prospectively related to FG level changes and insulin secretion and action.

The Association of Lipids and Lipoproteins with Hip Fracture Risk: The Cardiovascular Health Study

BACKGROUND

It is uncertain if lipids or lipoproteins are associated with osteoporotic fractures. In this study, incident hip fracture risk according to conventional lipid levels and lipoprotein levels and sizes was examined.

METHODS

We followed 5832 participants aged ≥65 years from the Cardiovascular Health Study for hip fracture for a mean of 13.5 (SD 5.7) years. Standard enzymatic methods were used to determine lipid levels (ie, high-density lipoprotein-cholesterol [HDL-c], low-density lipoprotein-cholesterol [LDL-c], and triglycerides). Nuclear magnetic resonance spectroscopy was used to measure lipoprotein fractions (ie, very-low-density lipoprotein-particle [VLDL-P], low-density lipoprotein-particle [LDL-P], high-density lipoprotein-particle [HDL-P]) in a subset of 1849 participants.

RESULTS

We documented 755 incident hip fractures among women (1.19 fractures per 100 participant years [95% confidence interval, 1.04, 1.35]) and 197 among men (0.67 fractures per 100 participant years [95% CI, 0.41, 1.10]) over an average follow-up. HDL-c and LDL-c levels had statistically significant nonlinear U-shaped relationships with hip fracture risk (HDL-c, P = .009; LDL-c, P = .02). Triglyceride levels were not significantly associated with hip fracture risk. In fully adjusted conjoint models, higher VLDL-P concentration (hazard ratio [HR] per 1 standard deviation [SD] increment 1.47 [1.13, 1.91] and size [HR per 1 SD increment 1.24 [1.05, 1.46]) and higher high-density lipoprotein particle size (HR per 1 SD increment 1.81 [1.25, 2.62]) were all associated with higher hip fracture risk.

CONCLUSIONS

Lipids and lipoproteins are associated with hip fracture risk in older adults. The associations are complex. Mechanistic studies are needed to understand these findings.

Trimethylamine N-oxide and hip fracture and bone mineral density in older adults: The cardiovascular health study

CONTEXT

Gut microbiota-derived metabolite trimethylamine N-oxide (TMAO) may adversely affect bone by inducing oxidative stress. Whether this translates into increased fracture risk in older adults is uncertain.

OBJECTIVE

Determine the associations of plasma TMAO with hip fracture and bone mineral density (BMD) in older adults.

DESIGN AND SETTING

Cox hazard models and linear regression stratified by sex examined the associations of TMAO with hip fracture and BMD in the longitudinal cohort of the Cardiovascular Health Study.

PARTICIPANTS

5019 U.S. adults aged ≥65 years.

EXPOSURE

Plasma TMAO.

MAIN OUTCOME MEASURES

Incident hip fractures; total hip BMD dual x-ray absorptiometry in a subset (n = 1400).

RESULTS

Six hundred sixty-six incident hip fractures occurred during up to 26 years of follow-up (67,574 person-years). After multivariable adjustment, TMAO was not significantly associated with hip fracture (women: hazard ratio (HR) [95% confidence interval (CI)] of 1.00[0.92,1.09] per TMAO doubling; men: 1.12[0.95,1.33]). TMAO was also not associated with total hip BMD (women: BMD difference [95% CI] of 0.42 g/cm2*100 [-0.34,1.17] per TMAO doubling; men: 0.19[-1.04,1.42]). In exploratory analyses, we found an interaction between body mass index (BMI) and the association of TMAO with hip fracture (P < 0.01). Higher TMAO was significantly associated with risk of hip fracture in adults with overweight or obesity (BMI ≥ 25) (HR [95% CI]:1.17[1.05,1.31]), but not normal or underweight.

CONCLUSIONS

Among older US men and women, TMAO was not significantly associated with risk of hip fracture or BMD overall. Exploratory analyses suggested a significant association between higher TMAO and hip fracture when BMI was elevated, which merits further study.

The cross-sectional association of cognition with diabetic peripheral and autonomic neuropathy-The GRADE study

BACKGROUND

Studies examining whether measures of cognition are related to the presence of diabetic peripheral neuropathy (DPN) and/or cardiovascular autonomic neuropathy (CAN) are lacking, as are data regarding factors potentially explaining such associations.

METHODS

Participants were from the Glycemia Reduction Approaches in Diabetes Study (GRADE) that examined 5047 middle-aged people with type 2 diabetes of <10 years of known duration. Verbal learning and immediate and delayed recall (memory) were assessed with the Spanish English Verbal Learning Test; frontal executive function and processing speed with the Digit Symbol Substitution Test; and ability to concentrate and organize data with word and animal fluency tests. DPN was assessed with the Michigan Neuropathy Screening Instrument and CAN by indices of heart rate variability (standard deviation of normal beat to beat variation [SDNN] and root mean square of successive differences [RMSSD]).

RESULTS

DPN was significantly inversely related to measures of immediate recall and processing speed. The percent of cognitive variation explained by DPN was small. Tests of CAN had an inconsistent or absent association with measures of cognition. Higher waist circumference and urine albumin creatinine (UACR) levels were the strongest correlates in the relationship between DPN and cognitive impairment.

CONCLUSION

DPN, but not CAN, was cross-sectionally associated with lower performance in measures of cognition in people with type 2 diabetes of <10 years of known duration. Greater waist circumference and UACR were important variables in this association. The mechanisms underlying the cross-sectional association of DPN with cognitive impairment are unknown. Clinicaltrials.gov: NCT01794143.

Serum non-esterified fatty acid levels and hip fracture risk: The Cardiovascular Health Study

Among elderly participants from the Cardiovascular Health Study, we found that non-esterified trans fatty acid levels had a significant prospective association with hip fracture risk. Other non-esterified fatty acid classes were not associated with hip fracture risk.

INTRODUCTION

Serum non-esterified fatty acids (NEFAs) are bioactive metabolic intermediates that can be taken up by bone tissue. Their associations with hip fracture risk have not been previously examined.

METHODS

Thirty-five individual NEFAs in five classes (saturated [SFA], mono-un-saturated [MUFA], poly-unsaturated n-6 and n-3 [PUFA], and trans-FA) were measured in Cardiovascular Health Study participants (n = 2139, mean age 77.8 years) without known diabetes. The multivariable associations of NEFA levels with hip fracture risk were evaluated in Cox hazards models.

RESULTS

We documented 303 incident hip fractures during 11.1 years of follow-up. Among the five NEFA classes, total trans FA levels were positively associated with higher hip fracture risk (HR 1.17 [95% CI, 1.04, 1.31; p = 0.01] per one standard deviation higher level). The SFA lignoceric acid (24:0) was positively associated with higher risk (HR 1.09 [1.04, 1.1]; p < 0.001), while behenic (22:0) and docosatetraenoic (22:4 n6) acids were associated with lower risk (HR 0.76 [0.61, 0.94]; p = 0.01; 0.84 [0.70, 1.00]; p = 0.05, respectively).

CONCLUSION

Total plasma trans NEFA levels are related to hip fracture risk, suggesting an unrecognized benefit of their systematic removal from food. Novel associations of individual NEFAs with hip fracture risk require confirmation in other cohort studies.

Shape of the OGTT glucose response curve: relationship with β-cell function and differences by sex, race, and BMI in adults with early type 2 diabetes treated with metformin

INTRODUCTION

The shape of the glucose curve during an oral glucose tolerance test (OGTT) reflects β-cell function in populations without diabetes but has not been as well studied in those with diabetes. A monophasic shape has been associated with higher risk of diabetes, while a biphasic pattern has been associated with lower risk. We sought to determine if phenotypic or metabolic characteristics were associated with glucose response curve shape in adults with type 2 diabetes treated with metformin alone.

RESEARCH DESIGN AND METHODS

This is a cross-sectional analysis of 3108 metformin-treated adults with type 2 diabetes diagnosed <10 years who underwent 2-hour 75 g OGTT at baseline as part of the Glycemia Reduction Approaches in Diabetes: A Comparative Effectiveness Study (GRADE). Insulin sensitivity (homeostasis model of insulin sensitivity, HOMA2-S) and β-cell function (early, late, and total incremental insulin and C peptide responses adjusted for HOMA2-S) were calculated. Glucose curve shape was classified as monophasic, biphasic, or continuous rise.

RESULTS

The monophasic profile was the most common (67.8% monophasic, 5.5% biphasic, 26.7% continuous rise). The monophasic subgroup was younger, more likely male and white, and had higher body mass index (BMI), while the continuous rise subgroup was more likely female and African American/black. HOMA2-S and fasting glucose did not differ among the subgroups. The biphasic subgroup had the highest early, late, and total insulin and C peptide responses (all p<0.05 vs monophasic and continuous rise). Compared with the monophasic subgroup, the continuous rise subgroup had similar early insulin (p=0.3) and C peptide (p=0.6) responses but lower late insulin (p<0.001) and total insulin (p=0.008) and C peptide (p<0.001) responses.

CONCLUSIONS

Based on the large multiethnic GRADE cohort, sex, race, age, and BMI were found to be important determinants of the shape of the glucose response curve. A pattern of a continuously rising glucose at 2 hours reflected reduced β-cell function and may portend increased glycemic failure rates.

TRIAL REGISTRATION NUMBER

NCT01794143.

Urine creatinine concentration and clinical outcomes in older adults: The Cardiovascular Health Study

PURPOSE

Loss of muscle mass and strength are associated with long-term adverse health outcomes in older adults. Urine creatinine concentrations (Ucr; mg/dl) are a measure of muscle tissue mass and turnover. This study assessed the associations of a spot Ucr level with muscle mass and with risk of hospitalization, mortality, and diabetes mellitus in older adults.

METHODS

We examined 3424 participants from the Cardiovascular Health Study who provided spot urine samples in 1996-1997 and who were followed through June 2015. All participants underwent baseline measurement of grip strength. In a sub-cohort, 1331 participants underwent dual energy X-ray absorptiometry (DEXA) scans, from which lean muscle mass was derived. Participants were followed for a median of 10 years for hospitalizations and mortality, and 9 years for diabetes mellitus.

RESULTS

In linear regression analysis, a one standard deviation higher Ucr concentration (64.6 mg/dl) was associated with greater grip strength (kg force) β = 0.44 [0.16, 0.72]; p = 0.002) and higher lean muscle mass (kg) (β = 0.43 [0.08, 0.78]; p = 0.02). In Cox regression analyses, each standard deviation greater Ucr concentration was associated with lower rates of hospitalizations (0.94 [95% confidence interval, 0.90, 0.98]; p < 0.001) and lower mortality risk (0.92 [0.88, 0.97]; p < 0.001), while a one standard deviation increase in muscle mass derived from DEXA had no such significant association. Ucr levels were not associated with incident diabetes mellitus risk (0.97 [0.85, 1.11]; p = 0.65).

CONCLUSION

A higher spot Ucr concentration was favorably associated with muscle mass and strength and with health outcomes in older community-living adults. The ease of obtaining a spot Ucr makes it an attractive analyte to use for gauging the health of older adults.

The cross-sectional association of renal dysfunction with tests of cognition in middle-aged adults with early type 2 diabetes: The GRADE Study

OBJECTIVE

The association of renal dysfunction with tests of cognition in type 2 diabetes has been examined in individuals with moderate and advanced renal disease. Here we examine the association of renal dysfunction with tests of cognition in a cohort of middle-aged adults with short duration diabetes (mean 4.0 ± 2.8 years).

METHODS

Baseline data were examined from the Glycemia Reduction Approaches in Diabetes (GRADE) study (n = 4998). Renal dysfunction was defined by the presence of albumin in the urine or by estimated glomerular filtration rate (eGFR). Cognition was assessed with the Spanish English Verbal Learning Test, Letter and Animal fluency tests, and the Digit Symbol Substitution Test.

RESULTS

Participants with albuminuria or eGFR <60 ml/min/1.73 m2 had significantly lower test scores of information processing speed and perception, executive function and ability to categorize information, and of verbal learning and memory compared to participants without renal disease. Adjustment for hypertension, dyslipidemia, and waist circumference attenuated many of these findings but markers of impaired learning and executive function continued to remain lower in association with higher urine albumin levels.

CONCLUSION

In type 2 diabetes of short duration, there are already subtle deficiencies in markers of cognition in association with renal disease in middle aged adults.

Hospitalization Rates in Older Adults With Albuminuria: The Cardiovascular Health Study

BACKGROUND

Albuminuria is highly prevalent among older adults, especially those with diabetes. It is associated with several chronic diseases, but its overall impact on the health of older adults, as measured by hospitalization, has not been quantified.

METHOD

We followed up 3,110 adults, mean age 78 years, for a median 9.75 years, of whom 654 (21%) had albuminuria (≥30 mg albumin/gram creatinine) at baseline. Poisson regression models, adjusted for cardiovascular, renal, and demographic factors, were used to evaluate the association of albuminuria with all-cause and cause-specific hospitalizations, as defined by ICD, version 9, categories.

RESULTS

The rates of hospitalization per 100 patient-years were 65.85 for participants with albuminuria and 37.55 for participants without albuminuria. After adjustment for covariates, participants with albuminuria were more likely to be hospitalized for any cause than participants without albuminuria (incident rate ratio, 1.39 [95% confidence intervals, 1.27. 1.53]) and to experience more days in hospital (incident rate ratio 1.56 [1.37, 1.76]). The association of albuminuria with hospitalization was similar among participants with and without diabetes (adjusted incident rate ratio for albuminuria versus no albuminuria: diabetes 1.37 [1.11, 1.70], no diabetes 1.40 [1.26, 1.55]; p interaction nonsignificant). Albuminuria was significantly associated with hospitalization for circulatory, endocrine, genitourinary, respiratory, and injury categories.

CONCLUSIONS

Albuminuria in older adults is associated with an increased risk of hospitalization for a broad range of illnesses. Albuminuria in the presence or absence of diabetes appears to mark a generalized vulnerability to diseases of aging among older adults.

Soluble CD14 and CD14 Variants, Other Inflammatory Markers, and Glucose Dysregulation in Older Adults: The Cardiovascular Health Study

OBJECTIVE

Experimental studies have implicated soluble (s)CD14, an effector of lipopolysaccharide-induced inflammation, in insulin resistance, but its role in human metabolic endotoxemia has not been studied. We evaluated sCD14 in relation to dysglycemia in older adults and how this compares to other markers of inflammation.

RESEARCH DESIGN AND METHODS

We investigated associations of sCD14, interleukin-6 (IL-6), CRP, and white blood cell (WBC) count with insulin resistance (quantitative insulin-sensitivity check index and HOMA 2 of insulin resistance) and incident type 2 diabetes in a population-based cohort of older adults. We also assessed the causal role of sCD14 in insulin resistance using an instrumental variable approach by Mendelian randomization.

RESULTS

After adjustment for conventional risk factors, each of the four biomarkers showed positive cross-sectional associations with both insulin resistance measures. These associations persisted after mutual adjustment for all markers except sCD14. Over a median follow-up of 11.6 years, 466 cases of diabetes occurred. All biomarkers except sCD14 were positively associated with diabetes, although only WBC count remained associated (hazard ratio 1.43 per doubling [95% CI 1.07, 1.90]) after mutual adjustment. Instrumental variable analysis did not support a causal role for sCD14 in insulin resistance.

CONCLUSIONS

Among older adults, sCD14 was associated with insulin resistance, but this disappeared after adjustment for other biomarkers, showed no evidence of a causal basis, and was not accompanied by a similar association with diabetes. IL-6, CRP, and WBC count were each associated with insulin resistance and diabetes, WBC count most robustly. These findings do not support a central role for sCD14, but they highlight the preeminence of WBC count as an inflammatory measure of diabetes risk in this population.

Assessing risk factors of non-fatal outcomes amid a competing risk of mortality: the example of hip fracture

The Fine-Gray method is often used instead of Cox regression to account for competing risks of death in time-to-event analyses for non-fatal outcomes. A series of examples using well-known risk factors of hip fracture in an older cohort with substantial competing mortality demonstrates that the Fine-Gray approach can yield estimates that implausibly contradict long-established associations, while Cox regression preserves them. Cox regression is generally preferred for risk factor-outcome associations even in the presence of competing risk of death.

INTRODUCTION

Factors like age, sex, and race are associated not only with risk of hip fracture but also with mortality. Substantial misunderstanding remains regarding the appropriate statistical approach to account for the competing risk of mortality.

METHODS

In the Cardiovascular Health Study, an ongoing cohort study of 5888 older adults, we followed participants for incident hip fracture from their 1992-1993 visit through June 2014. We contrasted the conventional cause-specific Cox analysis, which censors individuals at the time of death, with the Fine-Gray (FG) approach, which extends participant follow-up even after death, to estimate the association of well-established demographic and clinical factors with incident hip fracture.

RESULTS

For age, current smoking and sex, Cox and FG methods yielded directionally concordant but quantitatively different strengths of association. For example, the Cox hazard ratio (HR) for a 5-year increment in age was 1.74 (95% CI, 1.61-1.87), while the corresponding FG HR was 1.16 (1.09-1.24). In contrast, the FG approach estimated a stronger association of hip fracture with sex. The two approaches yielded nearly identical results for race. For diabetes and kidney function, the estimates were discordant in direction, and the FG HRs suggested effects that were in the opposite direction of well-understood and widely accepted associations.

CONCLUSIONS

Cause-specific Cox models provide appropriate estimates of hazard for non-fatal outcomes like hip fracture even in the presence of competing risk of mortality. The Cox approach estimates hazard in the population of individuals who have not yet had an incident hip fracture and remain alive, which is typically the group of clinical interest. The Fine-Gray method estimates hazard in a hypothetical population that can yield misleading inferences about risk factors in populations of clinical interest.

Higher albumin:creatinine ratio and lower estimated glomerular filtration rate are potential risk factors for decline of physical performance in the elderly: the Cardiovascular Health Study

Introduction

Mildly reduced renal function and elevated urine protein levels are each prospectively associated with hip fracture risk in older adults. Here we determine whether these markers are associated with reduced appendicular muscle performance.

Methods

We prospectively examined the associations of urine albumin:creatinine ratio (ACR) and reduced estimated glomerular filtration rate (eGFR) with longitudinal changes in grip strength and gait speed >2 years in 2317 older community-dwelling men and women (median age 77 years). The median ACR was 9.8 [interquartile range (IQR) 5.40–21.50] mg/g creatinine and the median eGFR was 71.6 (IQR 59.1–83.56) mL/min/1.73 m². Models were adjusted for demographic factors, clinical history and biochemical measures in four candidate pathways: diabetes, oxidative stress, inflammation and fibrosis.

Results

In demographic- and covariate-adjusted models, a 2-fold higher baseline urine ACR was associated with longitudinal changes of −0.17 kg [95% confidence interval (CI) −0.29 to −0.06) in grip strength and −1.10 cm/s (95% CI −1.67 to −0.53) gait speed per year. Corresponding estimates for a 10 mL/min/1.73 m² lower baseline eGFR were −0.13 kg (95% CI −0.23 to −0.04) and −0.89 cm/s (95% CI −1.37 to −0.40), respectively. The associations of a 2-fold higher baseline ACR and a 10 mL/min/1.73 m² lower baseline eGFR using cystatin C with grip strength and gait speed were equivalent to ∼1.2–1.9 additional years of age. Adjustment for covariates in candidate pathways did not attenuate these estimates.

Conclusions

In older adults, higher ACR and lower eGFR are potential risk factors for a decline of physical performance >2 years.

The Interaction of a Diabetes Gene Risk Score With 3 Different Antihypertensive Medications for Incident Glucose-level Elevation

BACKGROUND

Elevations of fasting glucose (FG) levels are frequently encountered in people treated with thiazide diuretics. The risk is lower in people treated with ACE inhibitors (ACEi). To determine if genetic factors play a role in FG elevation, we examined the interaction of a diabetes gene risk score (GRS) with the use of 3 different antihypertensive medications.

METHODS

We examined 376 nondiabetic hypertensive individuals with baseline FG <100 mg/dl who were genotyped for 24 genes associated with risk of elevated glucose levels. All participants had ≥1 follow-up FG level over 6 years of follow-up. Participants were randomized to treatment with a thiazide-like diuretic (chlorthalidone), a calcium channel blocker (CCB; amlodipine), or an ACEi (lisinopril). Outcomes were an FG increase of ≥13 or ≥27 mg/dl, the upper 75% and 90% FG increase in the parent cohort from which the present cohort was obtained. Odds ratios were adjusted for factors that increase FG levels.

RESULTS

For every 1 allele increase in GRS, the adjusted odds ratios (ORs) were 1.06 (95% confidence interval (CI): 0.99, 1.14; P = 0.06) and 1.09 (95% CI: 0.99, 1.20; P = 0.08). When results were examined by randomized medications, participants randomized to amlodipine had statistically significant odds for either outcome (OR: 1.23; 95% CI: 1.03, 1.48; P = 0.01 and OR: 1.31; 95% CI: 1.06, 1.62; P = 0.01). No such risk increase was found in participants randomized to the other 2 medications.

CONCLUSIONS

A diabetes GRS predicts FG elevation in people treated with a CCB, but not with an ACEi or diuretic. These findings require confirmation.

CLINICAL TRIALS REGISTRATION

Trial number NCT00000542.

The associations of subclinical atherosclerotic cardiovascular disease with hip fracture risk and bone mineral density in elderly adults

In the absence of clinically recognized cardiovascular disease, increased carotid artery intimal medial thickness was associated with higher hip fracture risk in older adults, despite its association with higher bone mineral density (BMD). Low ankle brachial index and aortic wall thickness were not associated with fracture risk or BMD.

INTRODUCTION

Clinically recognized cardiovascular disease (CVD) is associated with osteoporosis and hip fracture risk, but the relationship of subclinical atherosclerosis to bone health is not certain.

METHODS

We followed 3385 participants from the Cardiovascular Health Study (mean age 74.7 ± 5.3 years) with a median time to fracture of 12.1 years who underwent baseline carotid artery and aortic wall ultrasound scanning and ankle brachial blood pressure index (ABI) determinations. A subset underwent bone mineral density (BMD) testing.

RESULTS

There were 494 hip fractures during follow-up. Among persons without clinical CVD, an average standard-deviation increase in a composite score of maximal common and internal carotid artery intimal medial thickness (cIMT) was associated with increased risk of hip fracture [(HR 1.18 [1.04, 1.35]), even though cIMT was positively associated with BMD. Neither aortic wall thickness nor ABI were associated with hip fracture risk or BMD. Among participants with clinical CVD, cIMT and aortic wall thickness, but not ABI, were associated with increased hip fracture risk.

CONCLUSION

Subclinical cIMT is associated with an increased risk of hip fractures despite being associated with increased BMD. This finding suggests that vascular health, even in its early stages, is linked to bone health, by pathways other than BMD.

Relationships between cerebral structure and cognitive function in African Americans with type 2 diabetes

BACKGROUND

Relationships between cognitive function and brain structure remain poorly defined in African Americans with type 2 diabetes.

METHODS

Cognitive testing and cerebral magnetic resonance imaging in African Americans from the Diabetes Heart Study Memory IN Diabetes (n = 480) and Action to Control Cardiovascular Risk in Diabetes MIND (n = 104) studies were examined for associations. Cerebral gray matter volume (GMV), white matter volume (WMV) and white matter lesion volume (WMLV) and cognitive performance (Mini-mental State Exam [MMSE and 3MSE], Digit Symbol Coding (DSC), Stroop test, and Rey Auditory Verbal Learning Test) were recorded. Multivariable models adjusted for age, sex, BMI, scanner, intracranial volume, education, diabetes duration, HbA1c, LDL-cholesterol, smoking, hypertension and cardiovascular disease assessed associations between cognitive tests and brain volumes by study and meta-analysis.

RESULTS

Mean(SD) participant age was 60.1(7.9) years, diabetes duration 12.1(7.7) years, and HbA1c 8.3(1.7)%. In the fully-adjusted meta-analysis, lower GMV associated with poorer global performance on MMSE/3MSE (β̂ = 7.1 × 10^-3, SE 2.4 × 10^-3, p = 3.6 × 10^-3), higher WMLV associated with poorer performance on DSC (β̂ = -3 × 10^-2, SE 6.4 × 10^-3, p = 5.2 × 10^-5) and higher WMV associated with poorer MMSE/3MSE performance (β̂ = -7.1 × 10^-3, SE = 2.4 × 10^-3, p = 3.6 × 10^-3).

CONCLUSIONS

In African Americans with diabetes, smaller GMV and increased WMLV associated with poorer performance on tests of global cognitive and executive function. These data suggest that WML burden and gray matter atrophy associate with cognitive performance independent of diabetes-related factors in this population.

Rapid eGFR change as a determinant of cardiovascular and renal disease outcomes and of mortality in hypertensive adults with and without type 2 diabetes

A rapid decline in estimated glomerular filtration rate over 2 years in a large hypertensive cohort was associated with similar risks for overall cardiovascular disease in people with or without diabetes mellitus, but with higher all-cause mortality, heart failure, and end stage renal disease risk in people with diabetes.

The Effects of eGFR Change on CVD, Renal, and Mortality Outcomes in a Hypertensive Cohort Treated With 3 Different Antihypertensive Medications

BACKGROUND

Impaired renal function is a risk factor for cardiovascular disease, end-stage renal disease (ESRD), and mortality. The impact of short-term renal function decline on outcomes is less well studied. The association of antihypertensive medications with the impact of short-term estimated glomerular filtration rate (eGFR) decline is not known.

METHODS

We examined 20,207 hypertensive participants with baseline and 2-year creatinine levels from which eGFR changes were estimated. The associations between eGFR change with incident coronary heart disease (CHD), stroke, heart failure (HF), all-cause mortality, and ESRD during 2.9 years of in-trial follow up, and with mortality during in-trial and post-trial follow-up (7.6 years), were studied. Results were assessed by primary hypertension (HTN) treatment (chlorthalidone, lisinopril, and amlodipine) and adjusted for baseline eGFR levels.

RESULTS

In the short run, an eGFR decline below the cohort median (-1.28 ml/minute/1.73 m2/2 years) vs. above the median, or a 5 ml/min/1.73 m2/year decline vs. no decline, was associated with significant hazard risk for CHD (1.06-1.28), HF (1.24-1.91), ESRD (2.84-6.01), and mortality (1.08-1.19), but not with stroke risk. In the long term, there was a significant association with mortality (1.11-1.34). Interaction terms for outcomes by antihypertensive treatments were not statistically significant except for ESRD between amlodipine vs. chlorthalidone (hazard ratio: 3.17 [2.59, 3.88] vs. 2.41 [1.98, 2.97]; P interaction = 0.005) for a 5 ml/min/1.73 m2/year eGFR decline.

CONCLUSION

Decline in eGFR over 2 years is associated with increased risk of clinical outcomes beyond the effects of baseline eGFR. These risks were the same irrespective of the primary medication used to treat HTN.

Associations of Early Kidney Disease With Brain Magnetic Resonance Imaging and Cognitive Function in African Americans With Type 2 Diabetes Mellitus

BACKGROUND

Relationships between early kidney disease, neurocognitive function, and brain anatomy are poorly defined in African Americans with type 2 diabetes mellitus (T2DM).

STUDY DESIGN

Cross-sectional associations were assessed between cerebral anatomy and cognitive performance with estimated glomerular filtration rate (eGFR) and urine albumin-creatinine ratio (UACR) in African Americans with T2DM.

SETTING & PARTICIPANTS

African Americans with cognitive testing and cerebral magnetic resonance imaging (MRI) in the African American-Diabetes Heart Study Memory in Diabetes (AA-DHS MIND; n=512; 480 with MRI) and Action to Control Cardiovascular Risk in Diabetes (ACCORD) MIND (n=484; 104 with MRI) studies.

PREDICTORS

eGFR (CKD-EPI creatinine equation), spot UACR.

MEASUREMENTS

MRI-based cerebral white matter volume (WMV), gray matter volume (GMV), and white matter lesion volume; cognitive performance (Mini-Mental State Examination, Digit Symbol Coding, Stroop Test, and Rey Auditory Verbal Learning Test). Multivariable models adjusted for age, sex, body mass index, scanner, intracranial volume, education, diabetes duration, hemoglobin A_1c concentration, low-density lipoprotein cholesterol concentration, smoking, hypertension, and cardiovascular disease were used to test for associations between kidney phenotypes and the brain in each study; a meta-analysis was performed.

RESULTS

Mean participant age was 60.1±7.9 (SD) years; diabetes duration, 12.1±7.7 years; hemoglobin A_1c concentration, 8.3%±1.7%; eGFR, 88.7±21.6mL/min/1.73m²; and UACR, 119.2±336.4mg/g. In the fully adjusted meta-analysis, higher GMV associated with lower UACR (P<0.05), with a trend toward association with higher eGFR. Higher white matter lesion volume was associated with higher UACR (P<0.05) and lower eGFR (P<0.001). WMV was not associated with either kidney parameter. Higher UACR was associated with lower Digit Symbol Coding performance (P<0.001) and a trend toward association with higher Stroop interference; eGFR was not associated with cognitive tests.

LIMITATIONS

Cross-sectional; single UACR measurement.

CONCLUSIONS

In African Americans with T2DM, mildly high UACR and mildly low eGFR were associated with smaller GMV and increased white matter lesion volume. UACR was associated with poorer processing speed and working memory.

Association of Increased Urinary Albumin With Risk of Incident Clinical Fracture and Rate of Hip Bone Loss: the Osteoporotic Fractures in Men Study

Prior studies suggest that increased urine albumin is associated with a heightened fracture risk in women, but results in men are unclear. We used data from Osteoporotic Fractures in Men (MrOS), a prospective cohort study of community-dwelling men aged ≥65 years, to evaluate the association of increased urine albumin with subsequent fractures and annualized rate of hip bone loss. We calculated albumin/creatinine ratio (ACR) from urine collected at the 2003-2005 visit. Subsequent clinical fractures were ascertained from triannual questionnaires and centrally adjudicated by review of radiographic reports. Total hip BMD was measured by DXA at the 2003-2005 visit and again an average of 3.5 years later. We estimated risk of incident clinical fracture using Cox proportional hazards models, and annualized BMD change using ANCOVA. Of 2982 men with calculable ACR, 9.4% had ACR ≥30 mg/g (albuminuria) and 1.0% had ACR ≥300 mg/g (macroalbuminuria). During a mean of 8.7 years of follow-up, 20.0% of men had an incident clinical fracture. In multivariate-adjusted models, neither higher ACR quintile (p for trend 0.75) nor albuminuria (HR versus no albuminuria, 0.89; 95% CI, 0.65 to 1.20) was associated with increased risk of incident clinical fracture. Increased urine albumin had a borderline significant, multivariate-adjusted, positive association with rate of total hip bone loss when modeled in ACR quintiles (p = 0.06), but not when modeled as albuminuria versus no albuminuria. Macroalbuminuria was associated with a higher rate of annualized hip bone loss compared to no albuminuria (-1.8% more annualized loss than in men with ACR <30 mg/g; p < 0.001), but the limited prevalence of macroalbuminuria precluded reliable estimates of its fracture associations. In these community-dwelling older men, we found no association between urine albumin levels and risk of incident clinical fracture, but found a borderline significant, positive association with rate of hip bone loss. © 2016 American Society for Bone and Mineral Research.

Association of 3 Different Antihypertensive Medications With Hip and Pelvic Fracture Risk in Older Adults: Secondary Analysis of a Randomized Clinical Trial

IMPORTANCE

On the basis of observational studies, the use of thiazide diuretics for the treatment of hypertension is associated with reduced fracture risk compared with nonuse. Data from randomized clinical trials are lacking.

OBJECTIVE

To examine whether the use of thiazide diuretics for the treatment of hypertension is associated with reduced fracture risk compared with nonuse.

DESIGN, SETTING, AND PARTICIPANTS

Using Veterans Affairs and Medicare claims data, this study examined hip and pelvic fracture hospitalizations in Antihypertensive and Lipid-Lowering Treatment to Prevent Heart Attack Trial participants randomized to first-step therapy with a thiazide-type diuretic (chlorthalidone), a calcium channel blocker (amlodipine besylate), or an angiotensin-converting enzyme inhibitor (lisinopril). Recruitment was from February 1994 to January 1998; in-trial follow-up ended in March 2002. The mean follow-up was 4.9 years. Posttrial follow-up was conducted through the end of 2006, using passive surveillance via national databases. For this secondary analysis, which used an intention-to-treat approach, data were analyzed from February 1, 1994, through December 31, 2006.

MAIN OUTCOMES AND MEASURES

Hip and pelvic fracture hospitalizations.

RESULTS

A total of 22 180 participants (mean [SD] age, 70.4 [6.7] years; 43.0% female; and 49.9% white non-Hispanic, 31.2% African American, and 19.1% other ethnic groups) were followed for up to 8 years (mean [SD], 4.9 [1.5] years) during masked therapy. After trial completion, 16 622 participants for whom claims data were available were followed for up to 5 additional years (mean [SD] total follow-up, 7.8 [3.1] years). During the trial, 338 fractures occurred. Participants randomized to receive chlorthalidone vs amlodipine or lisinopril had a lower risk of fracture on adjusted analyses (hazards ratio [HR], 0.79; 95% CI, 0.63-0.98; P = .04). Risk of fracture was significantly lower in participants randomized to receive chlorthalidone vs lisinopril (HR, 0.75; 95% CI, 0.58-0.98; P = .04) but not significantly different compared with those randomized to receive amlodipine (HR, 0.82; 95% CI, 0.63-1.08; P = .17). During the entire trial and posttrial period of follow-up, the cumulative incidence of fractures was nonsignificantly lower in participants randomized to receive chlorthalidone vs lisinopril or amlodipine (HR, 0.87; 95% CI, 0.74-1.03; P = .10) and vs each medication separately. In sensitivity analyses, when 1 year after randomization was used as the baseline (to allow for the effects of medications on bone to take effect), similar results were obtained for in-trial and in-trial plus posttrial follow-up.

CONCLUSIONS AND RELEVANCE

These findings from a large randomized clinical trial provide evidence of a beneficial effect of thiazide-type diuretic therapy in reducing hip and pelvic fracture risk compared with treatment with other antihypertensive medications.

TRIAL REGISTRATION

clinicaltrials.gov Identifier: NCT00000542.

Systemic markers of microvascular disease and bone mineral density in older adults : The cardiovascular health study

Here we report that abnormal brain white matter and, to a lesser extent, albuminuria are associated with reduced bone mineral density in the hip, spine, and total body in men and women. These findings may explain the increased hip fracture risk reported in some studies in association with microvascular disorders.

INTRODUCTION

Markers of microvascular disease have been individually associated with increased risk of osteoporotic fractures in some studies. Here, we examine whether these markers are associated with reduced bone mineral density (BMD) individually and together.

METHODS

BMD testing using dual x-ray absorptiometry of the hip, lumbar spine, and total body was performed in 1473 participants from the Cardiovascular Health Study (mean age ~ 78 years): 1215 were assessed for urinary albumin-creatinine ratio, 944 for abnormal white matter disease (AWMD) by brain MRI, and 541 for retinal vascular disease with fundus photographs. Linear regression models were used to evaluate the cross-sectional association of each marker with BMD accounting for potentially confounding factors.

RESULTS

AWMD was associated with lower hip, spine, and total body BMD in women (β -3.08 to -4.53; p < 0.01 for all) and lower hip and total body BMD in men (β -2.90 to -4.24; p = 0.01-0.03). Albuminuria was associated with lower hip (β -3.37; p = .05) and total body (β -3.21; p = .02) BMD in men, but not in women. The associations of AWMD and albuminuria with BMD persisted with mutual adjustment and appeared to be additive to each other. Retinal vascular disease was not associated with BMD in men or women.

CONCLUSION

AWMD and, to a lesser extent, albuminuria were independently associated with lower BMD, suggesting that microvascular disease may play a role in the pathogenesis of reduced BMD. These findings need to be confirmed by longitudinal studies.

CONSENSUS STATEMENT BY THE AMERICAN ASSOCIATION OF CLINICAL ENDOCRINOLOGISTS AND AMERICAN COLLEGE OF ENDOCRINOLOGY ON THE COMPREHENSIVE TYPE 2 DIABETES MANAGEMENT ALGORITHM--2015 EXECUTIVE SUMMARY

This document represents the official position of the American Association of Clinical Endocrinologists and the American College of Endocrinology. Where there were no randomized controlled trials or specific U.S. FDA labeling for issues in clinical practice, the participating clinical experts utilized their judgment and experience. Every effort was made to achieve consensus among the committee members. Position statements are meant to provide guidance, but they are not to be considered prescriptive for any individual patient and cannot replace the judgment of a clinician.

Soluble CD14 and fracture risk

Soluble CD14 (sCD14) is an inflammatory marker associated with osteoclasts. Using Cox proportional hazards models, we found a positive association between plasma levels of sCD14 and risk of incident fracture among participants in the Cardiovascular Health Study. sCD14 may be useful in identifying those at risk for fracture.

INTRODUCTION

Soluble CD14, a proinflammatory cytokine, is primarily derived from macrophages/monocytes that can differentiate into osteoclasts. The purpose of this study was to examine the relationship between sCD14 levels and osteoporotic fractures.

METHODS

In the Cardiovascular Health Study, 5462 men and women had sCD14 levels measured at baseline. Incident hip fractures (median follow-up time 12.5 years) and incident composite fractures (defined as the first hip, pelvis, humerus, or distal radius fracture, median follow-up 8.6 years) were identified from hospital discharge summaries and/or Medicare claims data. Cox proportional hazards models were used to model the association between sCD14 levels and time to incident hip or composite fracture, overall and as a function of race and gender.

RESULTS

In unadjusted models, there was a positive association between sCD14 levels (per 1 standard deviation increase, i.e., 361.6 ng/mL) and incident hip (HR, 1.26; 95 % CI, 1.17, 1.36) and composite (HR, 1.20; 95 % CI, 1.12, 1.28) fractures. When models were fully adjusted for demographics, lifestyle factors, and medication use, these associations were no longer significant. However, in whites, the association of sCD14 levels with hip fractures remained significant in fully adjusted models (HR, 1.11; 95 % CI, 1.01-1.23). Associations of sCD14 levels with hip and composite fracture did not differ between men and women.

CONCLUSIONS

In this large cohort of community-dwelling older adults, higher sCD14 levels were associated with an increased risk of incident hip fractures in whites.

Fibrosis markers, hip fracture risk, and bone density in older adults

We examined whether blood levels of two markers of fibrosis (transforming growth factor beta one (TGF-β1) and procollagen type III N-terminal propeptide (PIIINP)) are related to hip fracture risk and to bone mineral density (BMD). TGF-β1 levels were associated with lower hip fracture risk in women and with lower BMD in men. PIIINP levels were not associated with either outcome.

INTRODUCTION

TGF-β1 serves several roles in bone formation and resorption. A consequence of TGF-β1 activation is the production of PIIINP, a marker of collagen III deposition. Here, we explore whether these two biomarkers are related to incident hip fracture and bone mineral density (BMD) and whether their associations are modified by systemic inflammation, as measured by C-reactive protein (CRP) levels.

METHODS

Participants were from the Cardiovascular Health Study (mean age 78 years; mean follow-up 8.3 years). We included 1681 persons with measured levels of TGF-β1 (149 hip fractures) and 3226 persons with measured levels of PIIINP (310 hip fractures).

RESULTS

Among women, higher TGF-β1 levels were associated with lower hip fracture risk (HR, per doubling, 0.78 [95 % CI 0.61, 0.91]). Among men, TGF-β1 levels were associated with hip fracture risk in a non-linear manner, but among those with elevated CRP levels, doubling was associated with increased risk of fracture (HR 2.22 [1.20, 4.08]) (p = 0.02, interaction between low and high CRP and TGF-β1 on fracture risk). TGF-β1 levels had no significant association with total hip or total body BMD in women but were significantly associated with lower BMD in men. There were no associations of PIIINP levels with hip fracture risk or BMD in men or women.

CONCLUSIONS

TGF-β1 levels appear to be associated with bone-related phenotypes in a sex-specific manner. The reasons for these differences between men and women regarding TGF-β1 levels and hip fracture risk and bone density require further investigation.

Brain MRI Volume Findings in Diabetic Adults With Albuminuria: The ACCORD-MIND Study

BACKGROUND

Albuminuria is associated with cognitive impairment in people with type 2 diabetes mellitus (T2DM). The brain volume correlates of albuminuria in people with T2DM have not been well investigated.

METHODS

We examined 502 individuals with T2DM (9-12 years duration; mean age ~62 years) who had a brain MRI at baseline and at 40 months. Baseline MRI findings were examined by the presence or absence of albuminuria (≥30mg/g creatinine). Changes in MRI findings were examined by whether albuminuria was persistent, intermittent, or absent during follow-up.

RESULTS

At baseline, participants with albuminuria (28.7% of the cohort) had more abnormal white matter volume (AWMV) than participants without albuminuria on unadjusted analysis. This difference was attenuated with adjustment for systolic blood pressure, which was higher in participants with albuminuria than in those without albuminuria. During ~3.5 years of follow-up, participants with persistent albuminuria (15.8%) had a greater increase in new AWMV than participants without albuminuria (59.8%) or those with intermittent albuminuria on unadjusted analysis. This difference was attenuated with adjustment for age and systolic blood pressure. There were no significant differences in gray matter volume and total brain volume between participants with or without albuminuria at baseline or during follow-up. There was no significant effect modification of these findings by estimated glomerular filtration rate (eGFR) at baseline or change in eGFR during follow-up.

CONCLUSIONS

In this diabetic cohort, baseline albuminuria and persistent albuminuria were not independently associated with any significant differences in brain volume measurements compared with participants without albuminuria.

Relations of Postload and Fasting Glucose With Incident Cardiovascular Disease and Mortality Late in Life: The Cardiovascular Health Study

BACKGROUND

Older adults have a high prevalence of postload hyperglycemia. Postload glucose has shown more robust associations with cardiovascular disease (CVD) and death than fasting glucose, but data in the oldest old are sparse.

METHODS

Fasting and 2-hour postload glucose were measured in community-dwelling older adults, mean age 78, at the 1996-1997 follow-up visit of the Cardiovascular Health Study. We evaluated their associations with atherosclerotic CVD (ASCVD) and mortality using standard Cox regression and competing-risks analyses and assessed improvement in prediction-model discrimination with the c-statistic.

RESULTS

Among 2,394 participants without treated diabetes and available data on glycemic measures, there were 579 ASCVD events and 1,698 deaths during median follow-up of 11.2 years. In fully adjusted models, both fasting and 2-hour glucose were associated with ASCVD (HR per SD, 1.13 [1.03-1.25] and 1.17 [1.07-1.28], respectively) and all-cause mortality (HR 1.12 [1.07-1.18] and 1.14 [1.08-1.20]). After mutual adjustment, however, the associations for fasting glucose with both outcomes were abolished, but those for postload glucose were largely unchanged. Consistent findings were observed for ASCVD in competing-risks models.

CONCLUSION

In adults surviving to advanced old age, postload glucose was associated with ASCVD and mortality independently of fasting glucose, but fasting glucose was not associated with these outcomes independently of postload glucose. These findings affirm the robust association of postload glucose with ASCVD and death late in life.

Association of Fetuin-A With Incident Fractures in Community-Dwelling Older Adults: The Cardiovascular Health Study

Fetuin-A, a serum protein that regulates calcium mineralization, has been associated with bone mineral density (BMD) in several cross-sectional human studies, suggesting a possible beneficial effect on clinically important measures of bone health. Fetuin-A and incidence of subsequent fracture was assessed in 4714 men and women ≥65 years of age. Proportional hazards models were used to estimate risk of incident hip (hospital discharge ICD-9 codes) and composite fracture (hip, pelvis, humerus, or proximal forearm; hospital discharge ICD-9 codes and Medicare claims data). A total of 576 participants had an incident hip fracture (median follow-up 11.2 years) and 768 had an incident composite fracture (median follow-up 6.9 years). In unadjusted analyses, there was no association between fetuin-A (per SD increase) and risk of hip fracture (hazard ratio [HR], 0.96; 95% CI, 0.88 to 1.05) or composite fracture (HR, 0.99; 95% CI, 0.92 to 1.06). Results were not significantly changed after adjustment for potential confounding variables. Analyses modeling fetuin-A in quartiles or within a subset with available BMD measures also showed no statistically significant association with risk of hip or composite fracture. Though fetuin-A was positively associated with areal BMD in partially adjusted models (total hip: β, 0.013 g/cm(2) ; 95% CI, 0.005 to 0.021; femoral neck: β, 0.011 g/cm(2) ; 95% CI, 0.004 to 0.018; and lumbar spine: β, 0.007 g/cm(2) ; 95% CI, 0.001 to 0.028), these associations were no longer significant after further adjustment for BMI and in final multivariate models. In this large sample of community-dwelling older adults, a small positive association between fetuin-A and areal BMD appeared attributable to confounding variables and we found no evidence of an association between fetuin-A and risk of clinical fracture.

Association of levels of fasting glucose and insulin with rare variants at the chromosome 11p11.2-MADD locus: Cohorts for Heart and Aging Research in Genomic Epidemiology (CHARGE) Consortium Targeted Sequencing Study

BACKGROUND

Common variation at the 11p11.2 locus, encompassing MADD, ACP2, NR1H3, MYBPC3, and SPI1, has been associated in genome-wide association studies with fasting glucose and insulin (FI). In the Cohorts for Heart and Aging Research in Genomic Epidemiology Targeted Sequencing Study, we sequenced 5 gene regions at 11p11.2 to identify rare, potentially functional variants influencing fasting glucose or FI levels.

METHODS AND RESULTS

Sequencing (mean depth, 38×) across 16.1 kb in 3566 individuals without diabetes mellitus identified 653 variants, 79.9% of which were rare (minor allele frequency <1%) and novel. We analyzed rare variants in 5 gene regions with FI or fasting glucose using the sequence kernel association test. At NR1H3, 53 rare variants were jointly associated with FI (P=2.73×10(-3)); of these, 7 were predicted to have regulatory function and showed association with FI (P=1.28×10(-3)). Conditioning on 2 previously associated variants at MADD (rs7944584, rs10838687) did not attenuate this association, suggesting that there are >2 independent signals at 11p11.2. One predicted regulatory variant, chr11:47227430 (hg18; minor allele frequency=0.00068), contributed 20.6% to the overall sequence kernel association test score at NR1H3, lies in intron 2 of NR1H3, and is a predicted binding site for forkhead box A1 (FOXA1), a transcription factor associated with insulin regulation. In human HepG2 hepatoma cells, the rare chr11:47227430 A allele disrupted FOXA1 binding and reduced FOXA1-dependent transcriptional activity.

CONCLUSIONS

Sequencing at 11p11.2-NR1H3 identified rare variation associated with FI. One variant, chr11:47227430, seems to be functional, with the rare A allele reducing transcription factor FOXA1 binding and FOXA1-dependent transcriptional activity.

Ratio of urine albumin to creatinine attenuates the association of dementia with hip fracture risk

CONTEXT

Microvascular disease is a leading cause of cognitive impairment. Approximately 50% of people with a hip fracture have cognitive impairment.

OBJECTIVE

We tested the hypothesis that microvascular diseases of the brain (lacunar infarcts and white matter disease [WMD]), kidney (albuminuria [≥ 30 mg/g creatinine] and albumin creatinine ratio [ACR]), and eye (retinal vascular disorders) attenuate the association of cognitive impairment with hip fracture risk.

SETTING

The Cardiovascular Health Cognition Study.

PATIENTS

Three thousand, one-hundred six participants (mean age, ∼ 79 y; 8.84 y median follow-up) with cognitive testing. Subsets received ACR testing (n=2389), brain magnetic resonance imaging scans (n = 2094), and retinal photography (n = 1098).

MAIN OUTCOME MEASURE

Incident hip fracture.

RESULTS

There were 488 participants (16%) with mild cognitive impairment (MCI) and 564 (18%) with dementia. There were 337 incident hip fractures, of which 19% occurred in participants with MCI and 26% in participants with dementia. Adjusted hazard ratios (HR) and 95% confidence interval for hip fracture in participants with MCI were 2.45 (1.67-3.61) and for dementia 2.35 (1.57-3.52). With doubling of ACR, the HR for fracture was attenuated in participants with dementia compared with participants with normal cognition [interaction HR 0.70 (0.55-0.91)]. No such effect was found in participants with MCI. Albuminuria, lacunar infarcts, WMD, and retinal vascular disease (RVD) did not modify the association of dementia or MCI with hip fracture risk.

CONCLUSIONS

ACR attenuates part of the risk of hip fracture in people with dementia, suggesting that these disorders share a common pathogenesis.