Association of bone mineral density with albuminuria and estimated glomerular filtration rate: the Dong-gu Study

The effect of a body shape index (ABSI) and its interaction with low estimated glomerular filtration rate (eGFR) on osteoporosis in elderly Chinese

BACKGROUND

Both obesity and chronic kidney disease (CKD) contribute to osteoporosis risk, but the effect of a newly developed index (e.g., a body shape index, ABSI) of central obesity and its interaction with low estimated glomerular filtration rate (eGFR) on osteoporosis remains unknown.

METHODS

A total of 2534 Chinese individuals were enrolled in our ongoing cohort study: Osteoporosis Preventive Project. ABSI and eGFR were calculated as obesity-related indexes and renal function markers, respectively. A logistic regression model was used to estimate the association between osteoporosis and related clinical parameters (e.g., ABSI, eGFR), and to assess the additive and multiplicative interactions between risk factors and osteoporosis. Relative excess risk due to interaction (RERI), attributable proportion due to interaction (AP) and synergy index (SI) were calculated to assess the additive interaction.

RESULTS

High ABSI was significantly associated with an increased risk of osteoporosis in participants compared with the lowest quartile of ABSI in both crude and adjusted models. Individuals in the lower quartiles of eGFR had a significantly increased risk of osteoporosis compared with those in the highest quartiles in crude models. After adding age and other variables in the model, the association was abolished. In addition, after adjusting for variables, high ABSI with low eGFR (RERI: 0.45, 95% CI: 0.15-0.75; AP: 0.39, 95% CI: 0.17-0.60) still displayed a noticeable interaction on the risk of osteoporosis. The multiplicative interactive effect between high ABSI with low eGFR on osteoporosis was statistically significant in the multivariable-adjusted model (P < 0.05).

CONCLUSION

Our study indicated that higher ABSI increases the risk of osteoporosis independently and synergistically with low eGFR in Chinese elderly adults. The findings increase our understanding of the interactions of osteoporosis risk factors and may help provide potential interventions for osteoporosis.

Comparison between linear regression and four different machine learning methods in selecting risk factors for osteoporosis in a Chinese female aged cohort

BACKGROUND

Population aging is emerging as an increasingly acute challenge for countries around the world. One particular manifestation of this phenomenon is the impact of osteoporosis on individuals and national health systems. Previous studies of risk factors for osteoporosis were conducted using traditional statistical methods, but more recent efforts have turned to machine learning approaches. Most such efforts, however, treat the target variable (bone mineral density [BMD] or fracture rate) as a categorical one, which provides no quantitative information. The present study uses five different machine learning methods to analyze the risk factors for T-score of BMD, seeking to (1) compare the prediction accuracy between different machine learning methods and traditional multiple linear regression (MLR) and (2) rank the importance of 25 different risk factors.

METHODS

The study sample includes 24 412 women older than 55 years with 25 related variables, applying traditional MLR and five different machine learning methods: classification and regression tree, Naïve Bayes, random forest, stochastic gradient boosting, and eXtreme gradient boosting. The metrics used for model performance comparisons are the symmetric mean absolute percentage error, relative absolute error, root relative squared error, and root mean squared error.

RESULTS

Machine learning approaches outperformed MLR for all four prediction errors. The average importance ranking of each factor generated by the machine learning methods indicates that age is the most important factor determining T-score, followed by estimated glomerular filtration rate (eGFR), body mass index (BMI), uric acid (UA), and education level.

CONCLUSION

In a group of women older than 55 years, we demonstrated that machine learning methods provide superior performance in estimating T-Score, with age being the most important impact factor, followed by eGFR, BMI, UA, and education level.

Degree of Albuminuria is Associated With Increased Risk of Fragility Fractures Independent of Estimated GFR

Introduction

Fragility fractures are common in persons with chronic kidney disease (CKD); however, the association between fragility fractures and albuminuria is not well-studied. The primary objective of this study is to determine the association of albuminuria with incident risk of fragility fractures. The secondary objective is to examine the risk of fragility fracture by estimated glomerular filtration rate (eGFR) and Kidney Disease Improving Global Outcomes (KDIGO) risk categories.

Methods

Community dwelling adults residing in Alberta, Canada who had at least 1 creatinine and albuminuria measurement between April 1, 2008 and March 31, 2019 participated in the study (N = 2.72 million). Incident fragility fractures were identified using Canadian Chronic Disease Surveillance Systems Osteoporosis Working Group algorithms. Albuminuria was categorized as none/mild (albumin-to-creatinine ratio [ACR] <30 mg/g, protein-to-creatinine ratio [PCR] <150 mg/g, trace/negative dipstick); moderate (ACR 30-300 mg/g, PCR 150-500 mg/g, 1+ dipstick) or severe (ACR >300 mg/g, PCR >500 mg/g, ≥2+ dipstick). Multivariable analysis controlled for 42 variables.

Results

Patients with severe albuminuria had an increased risk of hip fracture (odds ratio [OR] = 1.37; 95% confidence interval [CI] 1.28, 1.47]), vertebral fracture (OR = 1.31; 95% CI 1.21, 1.41) and any-type fracture (OR = 1.22; 95% CI 1.17, 1.28) compared with patients with none/mild albuminuria. Patients in the most severe KDIGO risk category had an increased risk of hip fracture (OR = 1.22; 95% CI 1.16, 1.29), vertebral fracture (OR = 1.18; 95% CI 1.09, 1.26) and any type of fracture (OR = 1.25; 95% CI 1.21, 1.30).

Conclusion

This study demonstrates the important role of albuminuria as a risk factor for fragility fractures in CKD and may help inform risk stratification and prevention strategies in this high-risk population category.

Calcification of lower extremity arteries is related to the presence of osteoporosis in postmenopausal women with type 2 diabetes mellitus: a cross-sectional observational study

It is unknown whether there is any relationship between extremity arterial macroangiopathy and osteoporosis in type 2 diabetic mellitus (T2DM) patients. We provide evidence to show the association between lower extremity arterial calcification and the presence of osteoporosis in postmenopausal T2DM women, but not in T2DM men of similar age.

PURPOSE

To investigate the relationship between lower extremity arterial calcification and the presence of osteoporosis in type 2 diabetic mellitus (T2DM) patients.

METHODS

We performed a retrospective cross-sectional study in patients with T2DM. They were assigned into two groups (patients with or without vascular calcification) in both sexes. Clinical characteristics, presence of osteoporosis, and bone metabolic markers were compared. Arterial calcification was determined by ultrasonography examination. Osteoporosis was defined based on the measurements from dual-energy X-ray absorptiometry. The relationship between the lower extremity arterial calcification and the presence of osteoporosis was analyzed. Statistical analysis was performed in SPSS 26.0.

RESULTS

A total of 933 T2DM patients (535 men ≥ 50 years old, and 398 postmenopausal women) were identified and analyzed. A significant association between arterial calcification and osteoporosis was only observed in women, with a higher prevalence of osteoporosis observed in women with calcification (40.8%) than in women without calcification (26.9%) (P = 0.004). Compared to women without calcification, women with calcification had lower bone mineral densities in the hip (P < 0.001) and femoral neck (P < 0.001). Ordinal logistic regression analysis showed that women with calcification had a nearly 2-fold increased risk for osteoporosis, even after adjusting for age, duration of T2DM, body mass index, pulse pressure, clearance of creatinine, glycosylated hemoglobin, and fasting C-peptide. Similar differences were not identified between men with and without calcification.

CONCLUSION

Calcification of lower extremity arteries is related with the presence of osteoporosis in postmenopausal T2DM women.

Association between urine albumin to creatinine ratio and bone mineral density: a cross-sectional study

BACKGROUND

Studies on the association between urinary albumin to creatinine ratio (ACR) and bone mineral density (BMD) are still controversial.

AIMS

This study investigated the association between ACR and BMD in the general US population.

METHODS

This cross-sectional study identified 2007 individuals aged 40 or above years with complete and valid data on urinary albumin to creatinine ratio (ACR) and femoral neck, total femur and lumbar spine BMD from the National Health and Nutrition Examination Survey 2013-2014. ACR was directly measured with established methods. BMDs were measured by dual-energy X-ray absorptiometry (DXA). After adjusting for multiple covariates, we used general linear model (GLM) to compare the mean of BMD between the quartiles of ACR.

RESULTS

The mean age of participants in this study was 54.6 ± 11.3 years; 52.6% of them were female. ACR was negatively associated with BMD at femoral neck, total femur and lumbar spine (all P < 0.05). After adjusting for covariates, higher level of ACR quartile was associated with lower femoral neck BMD (P for trend = 0.032), but with not total femur and lumbar spine BMD (all P for trend > 0.05)).

CONCLUSION

ACR was negatively associated with femoral neck BMD in the general US population. Future studies are warranted to confirm our results.

The Association of Aspartate Aminotransferase/Alanine Aminotransferase Ratio with Diabetic Nephropathy in Patients with Type 2 Diabetes

PURPOSE

To investigate the relationship between aspartate aminotransferase to alanine aminotransferase ratio (AST/ALT) and diabetic nephropathy (DN).

PATIENTS AND METHODS

A total of 402 patients with type 2 diabetes mellitus were divided into three groups, such as normoalbuminuria (n = 196), microalbuminuria (n = 131) and macroalbuminuria (n = 75) groups. Basic information and laboratory results were collected. Serum AST/ALT, tumor necrosis factor-α (TNF-α), interleukin (IL)-2, IL-4, IL-6, IL-10 and interferon- γ (INF- γ) were also measured. DN was defined as microalbuminuria or macroalbuminuria. The estimated glomerular filtration rate (eGFR) was calculated using the following formula: 186 × (serum creatinine)^-1.154× (age)^-0.203× (0.742 if female).

RESULTS

The AST/ALT in the macroalbuminuria group was higher than in the microalbuminuria and normoalbuminuria groups. The concentrations of tumor necrosis factor-α (TNF-α), IL-2, IL-4, IL-10 and INF-γ in the macroalbuminuria group were significantly higher than those in the two other groups. Multivariate logistical analysis showed that after adjusting confounding factors, TNF-α and high AST/ALT were independent risks for DN and macroalbuminuria. Furthermore, the AST/ALT had significantly positive correlation with TNF-α (r = 0.101, P = 0.048), IL-4 (r = 0.185, P = 0.005) and IL-6 (r = 0.274, P < 0.001) levels.

CONCLUSION

This study showed that high AST/ALT was an independent risk factor for the DN. Additionally, AST/ALT was positively correlated with inflammation cytokines, such as TNF-α, IL-4 and IL-6 levels.

The relationship between atherosclerosis and bone mineral density in patients with type 2 diabetes depends on vascular calcifications and sex

It is unknown whether a relationship exists between bone mineral density (BMD) and atherosclerosis with or without vascular calcification. In our study, a negative correlation between carotid atherosclerosis and BMD was found in female T2DM patients with vascular calcification, but not in those without calcification and males.

INTRODUCTION

Atherosclerosis is considered associated with low bone mineral density (BMD). However, most previous studies focus on patients with arterial atherosclerosis with vascular calcification. It is still unknown whether a relationship exists between atherosclerosis and BMD in patients without calcification. It is also unknown if sex plays a role in this relationship.

METHODS

We performed a retrospective cross-sectional study, which included 1459 type 2 diabetes mellitus (T2DM) patients (648 males ≥ 50 years old, and 811 postmenopausal females). They were assigned to three groups: group 1 (patients without carotid plaques and without carotid calcification), group 2 (patients with carotid plaques but without carotid calcification), and group 3 (patients with carotid plaques and with carotid calcification). Clinical characteristics and BMD were compared. The relationship between atherosclerosis and BMD was determined by binary logistic regression analysis. Statistical analysis was performed using SPSS 25.0.

RESULTS

Significant differences were only observed in women. The percentage of osteoporosis was higher in group 3 (43.64%) than in groups 1 (34.82%) and 2 (32.14%) (P = 0.016). Low BMD was found in the lumbar (P = 0.032), hip (P < 0.001), and femoral neck (P < 0.001). The odds ratio for osteoporosis increased significantly in a score-dependent manner in postmenopausal female patients with calcified atherosclerosis, but not in uncalcified patients. In men, no differences or relationships were identified.

CONCLUSION

A negative correlation between carotid atherosclerosis and BMD was found in female T2DM patients with vascular calcification, but not in those without calcification. A similar relationship was not observed in male patients with or without calcification. Thus, the relationship between atherosclerosis and bone mineral density in patients with type 2 diabetes depends on vascular calcifications and sex.

Association between Bone Mineral Density and Severity of Chronic Kidney Disease

OBJECTIVE

We sought to evaluate the association between femoral neck (FN) and lumbar spine (LS) bone mineral densities (BMDs) with severity of chronic kidney disease (CKD) and prevalence of osteopenia or osteoporosis (OP) among the CKD group.

METHODS

Cross-sectional data from 11050 participants aged ≥20 years from the National Health and Nutrition Examination Survey (NHANES) were analyzed. Specifically, Pearson correlation was applied to analyze the relationship between BMD and estimated glomerular filtration rate (eGFR). General linear models (GLMs) were adjusted for potential confounders and used to analyze mean BMD, based on CKD and CKD stages.

RESULTS

FN BMD was positively correlated with the eGFR in the total and male CKD, but not in the female CKD population. LS BMD was not significantly associated with eGFR. After controlling for partial correlations, FN T-score was positively correlated with the eGFR in the total at-risk population. According to FN BMD, OP prevalence was positively associated with CKD stage. However, according to LS BMD, there was no significant association between OP and CKD stage.

CONCLUSION

Our results may explain the higher prevalence of hip fracture, relative to that of the spine, among CKD patients and generate meaningful insights to guide care, prevention, and treatment regimens for CKD patients. However, the fact that this was a cross-sectional study may limit the possibility of drawing concrete conclusions. Nevertheless, these findings open up a new frontier for further studies to uncover the higher decrease of FN BMD compared to LS BMD among CKD cases.

Proteinuria Is Associated With Increased Risk of Fragility Fracture in Men With or at Risk of HIV Infection

BACKGROUND

Proteinuria has been associated with bone loss and fractures in general population, but data in HIV-infected population are lacking.

SETTING

Prospective, multicenter cohort study of men with or at risk of HIV infection.

METHODS

Between 2006 and 2015, urine protein measurements and bone fracture histories were ascertained semiannually in 947 HIV-infected (HIV+) and 969 HIV-uninfected (HIV-) men aged 40 years or older. Proteinuria was defined as protein-to-creatinine ratio ≥200 mg/g at ≥2 consecutive visits. Outcome measures (1) all fractures (excluding fractures of skull, face, and digits) and (2) fragility fractures (fractures of vertebral column, femur, wrist, and humerus). Multivariable Cox proportional hazards models assessed the association between proteinuria and fracture after adjusting for additional risk factors.

RESULTS

The overall period prevalence of proteinuria was higher among HIV+ than HIV- (29% vs 6%, P < 0.001). Men with proteinuria had a significantly higher risk of fragility fracture compared with men without proteinuria [adjusted hazard ratio (aHR) = 2.29 (1.12-4.66)] and did not differ by HIV serostatus (p-interaction = 0.83). The risk of all fractures was not statistically different between men with or without proteinuria [aHR = 1.31 (0.84-2.05)]. Among HIV+ men, the association between confirmed proteinuria and fragility fracture was attenuated [aHR = 2.12 (0.95-4.73)] after additional adjustment for CD4 T-cell count/mm, history of AIDS, the presence of detectable plasma HIV-1 RNA, and cumulative exposure to tenofovir disoproxil fumarate.

CONCLUSIONS

Proteinuria was more common in HIV+ than in HIV- men and was a strong independent risk factor for fragility fracture regardless of HIV serostatus. Proteinuria should prompt consideration of a thorough evaluation for bone disease among HIV+ persons.

Microangiopathy is associated with bone loss in female type 2 diabetes mellitus patients

OBJECTIVE

Type 2 diabetes mellitus complicated with microvascular diseases can be used as a model to study the relationship between bone health and the microvascular situation.

METHODS

A total of 2,170 patients with type 2 diabetes mellitus (1,188 postmenopausal females and 982 males aged ⩾50 years) were included in our cross-sectional study. These patients were grouped according to 24-hour urine protein level: Group I (<30 mg), Group II (30-299 mg) and Group III (≥300 mg). Bone mineral density of the lumbar spine, hip and femoral neck was evaluated by dual-energy X-ray absorptiometry. Fundus oculi photography for diabetic retinopathy and 24-h urine protein for diabetic nephropathy were used as markers of microangiopathy in type 2 diabetes mellitus. Characteristics of the patients and bone mineral density were compared. Multivariate analysis was used to study the association between bone mineral density and microangiopathy. Statistical analysis was performed using SPSS 20.0. p < 0.05 was considered statistically significant.

RESULTS

Group III had the lowest bone mineral density level in both genders. Multivariate analysis revealed that microangiopathy was negatively correlated with bone mineral density in females (lumbar: r = -0.522, p < 0.001; hip: r = -0.301, p = 0.010; femoral neck: r = -0.314, p = 0.009), but not in males, after adjustment for age, body mass index, hypertension, hyperlipidemia, diabetic status, hepatic function, kidney function, sex hormones and 25(OH) vitamin D.

CONCLUSION

These results demonstrate an independent negative correlation between microangiopathy and bone mineral density in postmenopausal female type 2 diabetes mellitus patients.

Association between Bone Mineral Density and Albuminuria: Cross-Sectional Analysis of Data from the 2011 Korea National Health and Nutrition Examination Survey V-2

BACKGROUND

Albuminuria is known to be independently associated with progression of renal and cardiovascular disease. However, little is known regarding the exact relationship between albuminuria and bone mineral density (BMD). The aim of this population-based study conducted in Korea was to identify the association between albuminuria and BMD.

METHODS

We performed a cross-sectional analysis of data from the Korea National Health and Nutrition Examination Survey (KNHANES V-2) 2011. BMD was measured for total hip (TH), femur neck (FN), and lumbar spine (LS). Analysis of covariance was used to compare BMD levels between the groups at the TH, FN, and LS sites, after adjusting for age. Separate analyses were performed according to sex; women were divided into two groups according to menopausal status and each group was subdivided into three according to urine albumin-to-creatinine ratio (level 1, <30 mg/g; level 2, 30 to 299 mg/g; level 3, ≥300 mg/g).

RESULTS

Data on a total of 1,831 adults (857 men and 974 women) were analyzed. In postmenopausal women, after adjusting for age, BMD of TH tended to decrease as levels of albuminuria increased (0.767±0.117, 0.757±0.129, 0.752±0.118, respectively; P=0.040). However, there was no significant difference in BMD according to albuminuria level in premenopausal women and men.

CONCLUSION

Level of albuminuria was closely related with BMD of TH in postmenopausal women, after adjusting for age, but there was no significant relationship between albuminuria and BMD in premenopausal women and men.

Reduced kidney function is associated with BMD, bone loss and markers of mineral homeostasis in older women: a 10-year longitudinal study

Kidney function decreases with age; however, the long-term influence on bone density (BMD) in older women already at risk of osteoporosis is unknown. We followed kidney function and bone loss for 10 years. Declining kidney function was adversely associated with bone loss and mineral homeostasis in old women, though it attenuated with advanced aging.

INTRODUCTION

Existing studies do not fully address the relationship between kidney function and bone metabolism with advanced aging in Caucasian women. This study describes the association between kidney function, BMD, bone loss and bone metabolism in older women and provides a review of the available literature for context.

METHODS

We studied participants from the OPRA cohort with follow-up after 5 and 10 years. Using plasma cystatin C (cysC), estimated glomerular function rate (eGFR) was evaluated at age 75 (n = 981), 80 (n = 685) and 85 (n = 365). Women were stratified into "normal" function (CKD stages 1-2), "intermediate" (stage 3a) and "poor" (stages 3b-5), and outcome measures-BMD, bone loss and markers of mineral homeostasis-were compared.

RESULTS

Femoral neck (FN) BMD positively associated with kidney function at 75 years old ([Formula: see text] = 0.001, p = 0.028) and 80 years old ([Formula: see text] = 0.001, p = 0.001), although with small effect size. Prevalence of osteoporosis (FN T-score ≤ - 2.5) did not differ with kidney function. Measured at age 75, women with poor kidney function had higher annual percentage bone loss over 5 years compared to those with normal function (2.3%, 95% CI 1.8-2.8 versus 1.3%, 95% CI 1.1-1.5, p = 0.007), although not when measured from age 80 or 85. Additionally, markers of mineral homeostasis (PTH, phosphate, vitamin D, calcium), CRP and osteocalcin differed by kidney function.

CONCLUSIONS

In old women, kidney function is associated with BMD, bone loss and altered mineral homeostasis; probably, a relationship attenuated in the very elderly.

Relationship between plasma pentraxin 3 level and risk of chronic kidney disease in the Korean elderly: the Dong-gu study

Purpose This study investigated the cross-sectional association between chronic kidney disease (CKD) and plasma pentraxin 3 (PTX3) levels in a Korean population, in a community-based cohort study.

METHODS

A total of 1816 (891 men, 925 women) subjects were randomly selected from the cohort of participants for the final analyses. Plasma PTX3 concentration was determined using enzyme-linked immunosorbent assays. The participants were divided into four quartiles according to the PTX3 levels. Multivariate logistic regression was performed to evaluate the association between plasma PTX3 level and CKD. Covariates inserted into the multivariate model included smoking status, systolic blood pressure, body mass index, waist circumference, high-density lipoprotein, low-density lipoprotein uric acid, white blood cell count, and carotid intima-media thickness.

RESULTS

Compared to the lowest PTX3 group (Q1), a significantly higher risk of CKD was found in the highest group (Q4), with an odds ratio of 1.58 and 95% confidence interval of 1.18-2.11 (P for trend <0.001).

CONCLUSIONS

This study showed that higher plasma PTX3 levels are significantly associated with CKD risk. The biological mechanism remains unclear; therefore, further molecular investigation of association between CKD and PTX3 is needed.

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.