Li Yung Lui

BMD at multiple sites and risk of fracture of multiple types: long-term results from the Study of Osteoporotic Fractures.

In a large cohort of U.S. women aged 65 and older, we report the relationships of BMD measured at several sites, and subsequent fracture risk at multiple sites over >8 years of follow‐up. Although we found almost all fracture types to be related to low BMD, the overall proportion of fractures attributable to low BMD is modest.

Circulating sex hormones and breast cancer risk factors in postmenopausal women: reanalysis of 13 studies.

Background:Breast cancer risk for postmenopausal women is positively associated with circulating concentrations of oestrogens and androgens, but the determinants of these hormones are not well understood.Methods:Cross-sectional analyses of breast cancer risk factors and circulating hormone concentrations in more than 6000 postmenopausal women controls in 13 prospective studies.Results:Concentrations of all hormones were lower in older than younger women, with the largest difference for dehydroepiandrosterone sulphate (DHEAS), whereas sex hormone-binding globulin (SHBG) was higher in the older women. Androgens were lower in women with bilateral ovariectomy than in naturally postmenopausal women, with the largest difference for free testosterone. All hormones were higher in obese than lean women, with the largest difference for free oestradiol, whereas SHBG was lower in obese women. Smokers of 15+ cigarettes per day had higher levels of all hormones than non-smokers, with the largest difference for testosterone. Drinkers of 20+u2009g alcohol per day had higher levels of all hormones, but lower SHBG, than non-drinkers, with the largest difference for DHEAS. Hormone concentrations were not strongly related to age at menarche, parity, age at first full-term pregnancy or family history of breast cancer.Conclusion:Sex hormone concentrations were strongly associated with several established or suspected risk factors for breast cancer, and may mediate the effects of these factors on breast cancer risk.

Long-term Risk of Incident Vertebral Fractures

CONTEXTnVertebral fractures are the most common osteoporotic fracture. Women with low bone mineral density (BMD) and prevalent vertebral fractures have a greater risk of incident vertebral fractures over the short-term, but their absolute risk of vertebral fracture over the long-term is uncertain.nnnOBJECTIVEnTo examine the absolute risk of incident vertebral fracture by BMD and prevalent vertebral fracture status over 15 years.nnnDESIGN, SETTING, AND PARTICIPANTSnA total of 9704 white women were recruited at 4 US clinical centers and enrolled in the Study of Osteoporotic Fractures, a longitudinal cohort study. Of these, 2680 attended a clinic visit an average of 14.9 years after baseline; mean age of 68.8 years at entry and 83.8 years at follow-up. Mean Outcome Measure Incident vertebral fractures identified from lateral spinal radiographs defined as a decrease of at least 20% and 4 mm at any vertebral level. Prevalent vertebral fractures were identified on the baseline radiographs using vertebral morphometry. Bone mineral density was measured at the total hip and lumbar spine using dual-energy x-ray absorptiometry.nnnRESULTSnOf the 2680 women, 487 (18.2%) had an incident vertebral fracture including 163 of the 394 (41.4%) with a prevalent vertebral fracture at baseline and 324 of the 2286 (14.2%) without a prevalent vertebral fracture at baseline (odds ratio, 4.21; 95% confidence interval, 3.33-5.34). Low BMD was associated with an increased risk of incident vertebral fracture (odds ratio per 1 SD decrease in total hip BMD, 1.78 [95% confidence interval, 1.58-2.00]). The absolute risk of vertebral fracture ranged from 56% among women with total hip BMD T score of -2.5 or less and a prevalent vertebral fracture to 9% in women with normal BMD and no prevalent vertebral fracture.nnnCONCLUSIONSnLow BMD and prevalent vertebral fractures are independently related to new vertebral fractures over 15 years of follow-up. Women with a prevalent vertebral fracture have a substantially increased absolute risk of an incident fracture, especially if they have osteoporosis diagnosed by BMD.

Bone-Density Testing Interval and Transition to Osteoporosis in Older Women

BACKGROUNDnAlthough bone mineral density (BMD) testing to screen for osteoporosis (BMD T score, -2.50 or lower) is recommended for women 65 years of age or older, there are few data to guide decisions about the interval between BMD tests.nnnMETHODSnWe studied 4957 women, 67 years of age or older, with normal BMD (T score at the femoral neck and total hip, -1.00 or higher) or osteopenia (T score, -1.01 to -2.49) and with no history of hip or clinical vertebral fracture or of treatment for osteoporosis, followed prospectively for up to 15 years. The BMD testing interval was defined as the estimated time for 10% of women to make the transition to osteoporosis before having a hip or clinical vertebral fracture, with adjustment for estrogen use and clinical risk factors. Transitions from normal BMD and from three subgroups of osteopenia (mild, moderate, and advanced) were analyzed with the use of parametric cumulative incidence models. Incident hip and clinical vertebral fractures and initiation of treatment with bisphosphonates, calcitonin, or raloxifene were treated as competing risks.nnnRESULTSnThe estimated BMD testing interval was 16.8 years (95% confidence interval [CI], 11.5 to 24.6) for women with normal BMD, 17.3 years (95% CI, 13.9 to 21.5) for women with mild osteopenia, 4.7 years (95% CI, 4.2 to 5.2) for women with moderate osteopenia, and 1.1 years (95% CI, 1.0 to 1.3) for women with advanced osteopenia.nnnCONCLUSIONSnOur data indicate that osteoporosis would develop in less than 10% of older, postmenopausal women during rescreening intervals of approximately 15 years for women with normal bone density or mild osteopenia, 5 years for women with moderate osteopenia, and 1 year for women with advanced osteopenia. (Funded by the National Institutes of Health.).

A Comparison of Prediction Models for Fractures in Older Women: Is More Better

BACKGROUNDnA Web-based risk assessment tool (FRAX) using clinical risk factors with and without femoral neck bone mineral density (BMD) has been incorporated into clinical guidelines regarding treatment to prevent fractures. However, it is uncertain whether prediction with FRAX models is superior to that based on parsimonious models.nnnMETHODSnWe conducted a prospective cohort study in 6252 women 65 years or older to compare the value of FRAX models that include BMD with that of parsimonious models based on age and BMD alone for prediction of fractures. We also compared FRAX models without BMD with simple models based on age and fracture history alone. Fractures (hip, major osteoporotic [hip, clinical vertebral, wrist, or humerus], and any clinical fracture) were ascertained during 10 years of follow-up. Area under the curve (AUC) statistics from receiver operating characteristic curve analysis were compared between FRAX models and simple models.nnnRESULTSnThe AUC comparisons showed no differences between FRAX models with BMD and simple models with age and BMD alone in discriminating hip (AUC, 0.75 for the FRAX model and 0.76 for the simple model; P = .26), major osteoporotic (AUC, 0.68 for the FRAX model and 0.69 for the simple model; P = .51), and clinical fracture (AUC, 0.64 for the FRAX model and 0.63 for the simple model; P = .16). Similarly, performance of parsimonious models containing age and fracture history alone was nearly identical to that of FRAX models without BMD. The proportion of women in each quartile of predicted risk who actually experienced a fracture outcome did not differ between FRAX and simple models (P > or = .16).nnnCONCLUSIONnSimple models based on age and BMD alone or age and fracture history alone predicted 10-year risk of hip, major osteoporotic, and clinical fracture as well as more complex FRAX models.

Lipid-Lowering Drug Use and Breast Cancer in Older Women: A Prospective Study

OBJECTIVEnTo test the hypothesis that use of lipid-lowering drugs reduces the risk of breast cancer in older women.nnnMETHODSnThis was a multicenter prospective cohort study conducted at four community-based clinical centers in the United States, including 7528 Caucasian women, mean age 77 years. The main outcome measure was incident breast cancer confirmed by medical record and pathology reports identified over an average of 6.8 years (244 cases).nnnRESULTSnThe use of lipid-lowering drugs was reported by 576 women (7.7%). The age-adjusted incidence of breast cancer was 3.1/1000 person-years among statin users, 1.4 among women using other lipid-lowering agents, and 5.0 among nonusers. After adjustment for age and body weight, the relative risk (RR) of breast cancer among statin users was 0.28 (95% confidence intervals [CI] 0.09-0.86), and among women who used other lipid-lowering drugs, it was 0.37 (95% CI 0.14-0.99) in comparison to nonusers. The combined group of lipid-lowering drug users had a 68% reduction in the risk of breast cancer (95% CI 32%-85%). Further adjustment for hormone use, family history of breast cancer, mammography use, or other risk factors did not alter the results.nnnCONCLUSIONSnOlder women who use lipid-lowering drugs may have a reduced risk of breast cancer. Given the widespread use of statins in older women, these results could have a large public health impact. However, these findings need confirmation in other prospective studies, as they were based on a small number of breast cancer events.

Reliability and Validity of the Pittsburgh Sleep Quality Index and the Epworth Sleepiness Scale in Older Men

BACKGROUNDnThe Pittsburgh Sleep Quality Index (PSQI) and the Epworth Sleepiness Scale (ESS) are commonly used to quantify sleep and excessive daytime sleepiness in older adults. These measures, however, have not been comprehensively evaluated for their psychometrics in older men. We determined the internal consistency reliability and construct validity of the PSQI and ESS in a sample of older men.nnnMETHODSnParticipants were 3,059 men (mean age = 76.4 years) in the Osteoporotic Fractures in Men Study (MrOS) who completed the two questionnaires, wrist actigraphy, and a range of additional psychosocial and health measures.nnnRESULTSnInternal consistency was adequate for the PSQI (Cronbachs α =.69) and the ESS (α = .70) total scores. PSQI daytime dysfunction and sleep medications components were weakly associated with the total score, but their removal did not notably improve internal consistency. PSQI and ESS totals were associated with each other and with theoretically related variables (ie, actigraphic variables, depressive symptoms, mobility/instrumental activities of daily living, health-related quality of life) in expected directions. The PSQI differentiated participants reporting no sleep disorder from those reporting particular disorders more reliably than the ESS.nnnCONCLUSIONSnIn general, we found evidence of the internal consistency reliability and construct validity of the PSQI and ESS in older men. Despite low correlation with the PSQI global score, the PSQI daytime dysfunction and sleep medications components do not appreciably reduce the PSQI total scores reliability or validity in older men.

Self‐Reported Sleep and Nap Habits and Risk of Falls and Fractures in Older Women: The Study of Osteoporotic Fractures

OBJECTIVES: To test the association between self‐reported sleep and nap habits and risk of falls and fractures in a large cohort of older women.

Longitudinal Study of Changes in Hip Bone Mineral Density in Caucasian and African‐American Women

Objectives: To determine whether changes in hip bone mineral density (BMD) differ in Caucasian and African American women.

Validation of the Pittsburgh Sleep Quality Index and the Epworth Sleepiness Scale in older black and white women

OBJECTIVESnDespite routine use with older adults, the Pittsburgh Sleep Quality Index (PSQI) and Epworth Sleepiness Scale (ESS) have not been adequately validated in older samples, particularly those from diverse racial backgrounds. The objective of this study was to determine the reliability and validity of and to provide normative data for these questionnaires in community-dwelling older women.nnnMETHODSnParticipants were 306 black and 2662 white women aged ≥70 from the Study of Osteoporotic Fractures. Participants completed the PSQI and ESS; provided self-reported assessments of mood, cognition and functioning; and underwent wrist actigraphy for sleep-wake estimation.nnnRESULTSnGood internal consistency in both black and white women was demonstrated for the PSQI and ESS. Two PSQI subscales, however, were found to have inadequate reliability (Medications and Daytime Dysfunction). Both the PSQI and ESS were associated with theoretically similar measures in the expected directions. The PSQI also differentiated participants with no reported sleep disorder from those reporting at least one sleep disturbance, such as insomnia, sleep apnea and restless legs. The ESS only differentiated women reporting no sleep disorder from those reporting insomnia.nnnCONCLUSIONnIn general, findings suggest that the PSQI and ESS are internally consistent, valid measures of self-reported sleep problems in older women. Additional research is required to evaluate the impact of removing the Medications and Daytime Dysfunction PSQI subscales on this measures internal consistency in older women.