J. Leung

Does the use of ACE inhibitors or angiotensin receptor blockers affect bone loss in older men

SummaryIn a prospective cohort study of 5,995 older American men (MrOS), users of angiotensin-converting enzyme (ACE) inhibitors had a small but significant increase in bone loss at the hip over 4xa0years after adjustment for confounders. Use of angiotensin II AT1 receptor blockers (ARB) was not significantly associated with bone loss.IntroductionExperimental evidence suggests that angiotensin II promotes bone loss by its effects on osteoblasts. It is therefore plausible that ACE inhibitor and ARB may reduce rates of bone loss. The objective of this study is to examine the independent effects of ACE inhibitor and ARB on bone loss in older men.MethodsOut of 5,995 American men (87.2%) aged ≥65xa0years, 5,229 were followed up for an average of 4.6xa0years in a prospective six-center cohort study—The Osteoporotic Fractures in Men Study (MrOS). Bone mineral densities (BMD) at total hip, femoral neck, and trochanter were measured by Hologic densitometer (QDR 4500) at baseline and yearxa04.ResultsOut of 3,494 eligible subjects with complete data, 1,166 and 433 subjects reported use of ACE inhibitors and ARBs, respectively. When compared with nonusers, continuous use of ACE inhibitors was associated with a small (0.004xa0g/cm2) but significant increase in the average rate of BMD loss at total hip and trochanter over 4xa0years after adjustment for confounders. Use of ARB was not significantly associated with bone loss.ConclusionUse of ACE inhibitors but not ARB may marginally increase bone loss in older men.

Dietary intake, blood pressure and osteoporosis.

Both hypertension and osteoporosis have common underlying nutritional aetiology, with regards to dietary cations intake. We tested the hypothesis that sodium intake reflected in urinary Na/Cr and blood pressure would be negatively associated with bone mineral density (BMD), whereas other cations may have opposite associations. Subjects were part of a study of bone health in 4000 men and women aged 65 years and over. A total of 1098 subjects who were not on antihypertensive drugs or calcium supplements and who provided urine samples were available for analysis. Logistic regression was used to examine associations between total hip and lumbar spine BMD, age, gender, body mass index (BMI), urinary Na/Cr, K/Cr, calcium and magnesium intake, systolic blood pressure and diastolic blood pressure. Total hip BMD was inversely associated with age, being female and urinary Na/Cr, and positively associated with BMI, urine K/Cr and dietary calcium intake. Lumbar spine BMD was inversely associated with being female and urinary Na/Cr, and positively associated with BMI, dietary calcium intake and SBP. We conclude that sodium intake, reflected by urinary Na/Cr, is the major factor linking blood pressure and osteoporosis as shown by the inverse relationship with BMD. The findings lend further emphasis to the health benefits of salt reduction in our population both in terms of hypertension and osteoporosis.

Predictive values of calcaneal quantitative ultrasound and dual energy X ray absorptiometry for non-vertebral fracture in older men: results from the MrOS study (Hong Kong)

SummaryCalcaneal QUS is comparable to DXA in predicting non-vertebral fractures in older Chinese men.IntroductionThe predictive values of calcaneal quantitative ultrasound (QUS) and dual-energy X-ray absorptiometry (DXA) for non-vertebral fractures in older Chinese men were examined.MethodsOne thousand nine hundred twenty-one Chinese men aged 65–92xa0years had calcaneal QUS and axial DXA bone mineral density (BMD) measurements. The incidence of non-vertebral fractures was documented. Cox regression and receiver operating curve (ROC) analysis were used to examine the associations of QUS parameters and BMD with the incidence of non-vertebral fractures.ResultsThe duration of follow-up was (mean±SD) 6.5u2009±u20091.7xa0years. One hundred thirty-one non-vertebral fractures were recorded, 71 of which were major fragility fractures. Broadband ultrasound attenuation (BUA) and quantitative ultrasound index (QUI) were significantly associated with non-vertebral fractures and major fragility fractures, with age and fracture history-adjusted hazard ratio (95% CI) of 1.23 (1.03, 1.47) and 1.32 (1.10, 1.59) per standard deviation reduction, respectively, for non-vertebral fractures; 1.32 (1.04, 1.68) and 1.43 (1.11, 1.84), respectively, for major fragility fractures. Age and fracture history-adjusted areas under ROC curves of hip or spine BMDs were significantly greater than that of BUA or QUI in predicting major fragility fractures, but not in predicting all non-vertebral fractures. The addition of BUA or QUI had no effect on AUCs of total hip BMD alone.ConclusionsThe ability of calcaneal QUS to predict non-vertebral fractures was comparable to that of axial BMD by DXA, but was inferior to BMD in predicting major fragility fractures in older Chinese men.

The selection of a screening test for frailty identification in community-dwelling older adults

BackgroundFrailty in older Chinese has been less often studied and the selection of one screening test feasible in primary care and population survey is needed. We attempted to examine the sensitivity and specificity of each of the five Fried’s criteria as a single screening test in the identification of frailty.MethodsWe recruited 4000 community-dwelling Chinese adults 65 years or older stratified by 3 age-stratum and identified frailty as having 3 or more of Fried’s criteria: underweight(BMI<18.5), handgrip strength(<lowest quintile), walking speed(<lowest quintile), self-reported exhaustion and low physical activity(PASE score<lowest quintile).ResultsThe proportion of frailty in the 3 age groups (65–69 years, 70–74 years, 75 years and above) were 2.3%, 3.4% and 11.9% respectively in men and 1.4%, 2.6% and 11.6% in women. Among the 5 criteria, walking speed, grip strength and physical activity (PASE score) divided at their respective lowest quintile values, achieved similar Area Under Curve in the Receiver Operating Characteristics analysis. For walking speed, the sensitivity and specificity were 82.7% and 83.1% in men and 91.9% and 84.5% in women respectively. For grip strength, the corresponding values were 89.5% and 80.6% in men; and 84.5% and 81.9% in women. For physical activity, they were 83.7% and 83.5% in men; and 82.8% and 84.7% in women.ConclusionEither walking speed or grip strength measurement may be suitable for frailty screening in primary care or population health survey. A cut-off value of 0.9 m/s in walking speed and 28 kg in grip strength for older men; and a corresponding value of 0.8 m/s and 18 kg for older women is recommended for the screening of frailty in community-dwelling older Chinese adults.

No Association between Dietary Vitamin K Intake and Fracture Risk in Chinese Community-Dwelling Older Men and Women: A Prospective Study

Data on the association between dietary vitamin K intake and fracture risk are limited among Chinese. This study examined such an association in community-dwelling elderly in Hong Kong. We present data from 2,944 subjects (1,605 men, 1,339 women) who participated in a prospective cohort study. Baseline dietary intakes of energy, protein, calcium, vitamin D, and vitamin K were assessed using a food-frequency questionnaire. Data on incident hip fracture and nonvertebral fracture during a median of 6.9 follow-up years were collected from a hospital database. Cox regression analyses were performed with adjustments for age, education attainment, smoking status, alcohol use, body mass index, hip bone mineral density, physical activity, use of calcium supplement, and energy-adjusted nutrient intakes. There were 29 (1.8xa0%) men and 19 (1.4xa0%) women with incident hip fractures and 97 (6.0xa0%) men and 88 (6.6xa0%) women with nonvertebral fractures. The median (interquartile range) of dietary vitamin K intake was 241.8 (157.5–360.8) and 238.9 (162.4–343.6) μg/day in men and women, respectively. Similar dietary vitamin K intakes were observed between subjects with hip or nonvertebral fractures and subjects without hip or nonvertebral fractures. In both men and women, dietary vitamin K intake was not associated with fracture risks at all measured sites in either crude or adjusted models. In Chinese community-dwelling elderly, hip or nonvertebral fracture risk was not associated with dietary vitamin K intake. The high dietary vitamin K intake of the studied group may have limited the ability to detect the association between vitamin K intake and fracture risk.

Associations of dietary protein intake on subsequent decline in muscle mass and physical functions over four years in ambulant older Chinese people

ObjectiveTo examine the association of dietary protein intake with 4-year change in physical performance measures and muscle mass in Chinese community-dwelling older people aged 65 and older in Hong Kong.DesignProspective cohort study design.SettingHong Kong, People’s of Republic of China.ParticipantsThere were 2,726 (1411 male, 1315 female) community-dwelling older people aged 65 and older.MeasurementsBaseline total, animal and vegetable protein intakes were collected using a validated food frequency questionnaire. Relative protein intake expressed as g/kg body weight was calculated and divided into quartiles for data analysis. Baseline and 4-year physical performance measures (normal and narrow 6-meters walking speed and step length in a 6-meters walk) were measured and 4-year change in appendicular skeletal muscle mass (ASM) from baseline was assessed by dual-energy X-ray absorptiometry. Univariate analysis identified age and sex as significant factors associated with change in physical performance measures or ASM, thus adjustments for these factors were made for subsequent analysis of covariance.ResultsMedian relative total protein intake was 1.3 g/kg body weight in men and 1.1 g/kg body weight in women. After adjustment for age and sex, relative total protein intake and animal protein intake were not associated with change in physical performance measures and ASM. In contrast, participants in the highest quartile (>0.72 g/kg body weight) of relative vegetable protein intake lost significantly less ASM over 4-year than those in the lowest quartile of relative vegetable protein intake (<=0.40 g/kg body weight) (adjusted mean ± SE: 0.270 ± 0.029 vs. 0.349 ± 0.030 kg, ptrend=0.025). There was no association between relative vegetable protein intake and change in physical performance measures.ConclusionsHigher protein intake from vegetable source was associated with reduced muscle loss in Chinese community-dwelling older people in Hong Kong whereas no association between total and animal protein intake and subsequent decline in muscle mass or physical performance measures was observed in this sample.

The added value of trabecular bone score to FRAX® to predict major osteoporotic fractures for clinical use in Chinese older people: the Mr. OS and Ms. OS cohort study in Hong Kong.

SummaryThe association of trabecular bone score (TBS) with fracture risk and its added predictive value to FRAX® for clinical use have never been independently evaluated in a Chinese population. TBS may improve the predictive power of FRAX® for clinical use in older Chinese men.IntroductionTrabecular bone score (TBS) of lumbar spine on Dual X-ray densitometry provides information on bone architecture. We therefore examined the additive value of TBS to FRAX® in predicting major osteoporotic fractures (MOFs) in older Chinese people.MethodsFour thousand community-dwelling Chinese men and women aged ≥65xa0years were followed up for fracture incidence for an average period of 9.94 and 8.82xa0years, respectively. At baseline, areal BMD of hip and lumbar spine were measured by DXA, TBS was estimated for the lumbar spine, and FRAX® for 10-year risk of MOFs (hip, clinical spine, shoulder, and wrist) was estimated. Cox regression model was used to evaluate the associations between TBS and FRAX® with the MOFs risk. The area under receiver-operating characteristic curve (AUC), integrated discrimination improvement (IDI), and category-based net reclassification improvement (NRI) were applied to evaluate the improved prediction ability.ResultsDuring the follow-up, 126 men and 215 women had at least one incident MOF. Each SD decrease in TBS was significantly associated with incident MOFs, with HR (95%CI) of 1.53 (1.30–1.80) and 1.40 (1.22–1.61) in men and women, respectively. TBS-adjusted FRAX® predicts better than FRAX® with a significantly increased AUC and IDI in men. Using specific intervention thresholds, TBS-adjusted FRAX® brings about 5xa0% overall correct reclassification for MOFs prediction than FRAX® in men. The increased correct MOFs risk classifications were not significant in older women.ConclusionsTBS-adjusted FRAX® may improve the predictive power of FRAX® on MOFs for clinical use in older Chinese men.

The ALU polymorphism of angiotensin I converting enzyme (ACE) and atherosclerosis, incident chronic diseases and mortality in an elderly Chinese population

ObjectiveWe examined the contribution of ACE I/D polymorphism in a large Chinese population to four year change in ankle-brachial index (ABI), development of cardiovascular diseases and mortality in a prospective study adjusting for many confounding factors.MethodData are drawn from a longitudinal study of 4000 community-living men and women aged 65 years and over, for which detailed information regarding lifestyle, chronic diseases, body mass index (BMI), ABI measurements and ACE polymorphisms were documented at baseline. During the fifth year of follow up, incident cardiovascular diseases, ABI, and mortality were documented, and related to ACE genotype adjusting for age, smoking, alcohol, dietary intake, physical activity, body mass index, and use of ACE inhibitors.ResultsWomen with the D/D genotype had the greatest reduction in mean ABI after adjusting for confounding factors. D/D genotype was also more common among women who developed hypertension or myocardial infarction. However D/D genotype was associated with mortality only in men.ConclusionIn a Chinese elderly population, ACE polymorphism may be considered’ deleterious’ to longevity, the D/D genotype being associated with mortality, the atherosclerotic process, hypertension and myocardial infarction. There are gender differences in the relationship between D/D genotype and cardiovascular diseases and mortality may not be mediated by the atherosclerotic process alone.

Added clinical use of trabecular bone score to BMD for major osteoporotic fracture prediction in older Chinese people: the Mr. OS and Ms. OS cohort study in Hong Kong

SummaryThe thresholds of trabecular bone score (TBS) require validation for clinical application in older Chinese people. The lower threshold of TBS significantly improved the accuracy of prediction by bone mineral density-based osteoporosis status for major osteoporotic fracture in older Chinese men.IntroductionTrabecular bone score (TBS) is a relatively new indicator of skeletal fragility. Its clinical application warrants further investigations. Our aim was to validate and recommend practical thresholds of TBS for fracture prediction in older Chinese people.MethodsOlder men and women in Mr. and Ms. Os (Hong Kong) study were followed up for an average of 9.94xa0±xa02.77 and 8.82xa0±xa01.49xa0years, respectively. Major osteoporotic fracture (MOF) risks of TBS category in each BMD category (normal, osteopenia, or osteoporosis) were compared using Poisson regression model. The improved fracture risk prediction power was evaluated by the sensitivity, the specificity, the area under the receiver-operating characteristic curve (AUC), and the net reclassification improvement index (NRI).ResultsMOF incidence gradually increased with the increased risk categories of bone mineral density (BMD) and tertiles of TBS both in men and women. Compared with the lowest risk category, the rate ratios (RR, 95xa0% CI) of MOF for osteoporosis with the lowest TBS was 9.66 (4.19–22.26) and 6.24 (1.53–25.42) in men and women, respectively. The fracture risk for osteopenic men with the lowest TBS was significantly higher than that for normal men, with RR (95xa0% CI) of 4.68 (2.11–10.41). The predictive power of osteoporosis alone was significantly improved by TBS in men [mean AUC (95xa0% CI) rose from 0.604 (0.562–0.646) to 0.666 (0.623–0.710) and sensitivity rose from 32.5 to 64.3xa0%]. The improvement in predictive power was not significant in older women.ConclusionsTBS in combination with BMD can predict MOF more reliably in older men than by BMD alone.

Does measurement of ankle‐brachial index contribute to prediction of adverse health outcomes in older Chinese people?

This study examined whether ankle‐brachial index (ABI) is predictive of all‐cause mortality, cardiovascular mortality, hospital admission for stroke, ischaemic heart disease or myocardial infarction among older people aged 65 years and above, and whether the inclusion of ABI in prediction models adds any incremental value to traditional cardiovascular risk factors.