Joel S Finkelstein

Boston Children's Hospital, Boston, Massachusetts, United States

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Publications (102)1175.38 Total impact

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    ABSTRACT: Patients with type 2 diabetes mellitus (DM2) have increased fracture risk. We found that African-American women with DM2 have increased cortical porosity and lower cortical bone density at the radius than non-diabetic controls. These cortical deficits are associated with hyperglycemia and may contribute to skeletal fragility associated with DM2.
    11/2014;
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    ABSTRACT: Proton pump inhibitors (PPIs) have been associated with diminished bone mineral density (BMD) and an increased risk of fracture, however prior studies have not yielded consistent results and many have sub-optimal ascertainment of both PPI use and BMD. We used data from the Study of Women's Health Across the Nation (SWAN), a multi-center, multi-ethnic community-based longitudinal cohort study of women across the menopause transition to examine the association between annualized BMD changes and new use of PPIs. We compared changes in BMD in new PPI users with changes in BMD in new users of Histamine 2 receptor antagonists (H2RAs) and with changes in BMD in subjects who did not use either class of medications. Mixed linear regression models included recognized risk factors for osteoporosis, including demographics, menopausal transition stage, BMI, lifestyle factors, as well as comorbidities and concomitant medications. To provide further evidence for the validity of our analytic approach, we also examined the effects of hormone therapy (HT), a class of medications that should reduce bone loss, on changes in BMD as an internal positive control group. We identified 207 new users of PPIs, 185 new users of H2RAs and 1,676 non-users. Study subjects had a mean age of 50 years and were followed for a median of 9.9 years. Adjusted models found no difference in the annualized BMD change at the lumbar spine, femoral neck or total hip in PPI users compared with H2RA users or non-users. These results were robust to sensitivity analyses. BMD increased as expected in HT users, supporting the validity of our study design. These longitudinal analyses plus similar prior studies argue against an association between PPI use and BMD loss. © 2014 American Society for Bone and Mineral Research
    Journal of bone and mineral research: the official journal of the American Society for Bone and Mineral Research 08/2014; · 6.04 Impact Factor
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    ABSTRACT: Context: Young adults with cystic fibrosis (CF) are at risk for low bone density and fractures, but the underlying alterations in bone microarchitecture that may contribute to their increased fracture risk are currently unknown. Objective: The main goal of this study was to utilize high resolution peripheral quantitative computed tomography (HR-pQCT) to characterize the bone micro-architecture, volumetric bone mineral density (vBMD), and estimated strength of the radius and tibia in young adults with CF compared to healthy volunteers. Design: Cross-sectional study. Setting: Outpatient clinical research center within a tertiary academic medical center. Participants: Thirty young adults with CF ages 18-40 years were evaluated and compared to 60 healthy volunteers matched by age (± 2 years), gender, and race. Intervention: N/A Main Outcome Measures: The primary outcomes were HR-pQCT-derived cortical and trabecular vBMD, bone microarchitecture, and estimates of bone strength. Results: At the radius and tibia, young adults with CF had smaller bone cross-sectional area and lower vBMD. Cortical and trabecular microarchitecture were compromised at both sites, most notably involving the trabecular bone of the tibia. These differences translated into lower estimated bone strength both at the radius and tibia. After accounting for BMI differences, young adults with CF had lower bone area and estimated bone strength at the radius and had compromised trabecular microarchitecture and lower total and trabecular vBMD and estimated bone strength at the tibia. Alterations in trabecular bone density and microarchitecture and estimated strength measures of the tibia were also greater than expected based on DXA-derived areal BMD differences. Conclusions: Young adults with CF have compromised bone microarchitecture and lower estimated bone strength at both the radius and tibia, even after accounting for their smaller body size. These skeletal deficits likely explain the higher fracture risk observed in young adults with CF.
    The Journal of clinical endocrinology and metabolism. 06/2014;
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    ABSTRACT: Context: In-vitro and animal studies have reported conflicting results regarding an independent role for FSH in the regulation of bone turnover. Objective: To test the hypothesis that suppressing serum FSH while holding serum gonadal steroid levels stable in the eugonadal range will affect biochemical markers of bone metabolism in healthy men. Design: Randomized controlled trial. Setting: Tertiary care academic teaching hospital. Participants: Eugonadal men aged 20-50. Interventions: Participants received monthly GnRH analog injections to suppress FSH secretion plus daily topical testosterone gel in pre-specified doses (Intervention Group). Controls received matching placebos (Control Group). Subjects in the intervention group were individually matched with subjects in the control group to ensure that the mean testosterone and estradiol levels (measured every 4 weeks during the 16 week study period) in the 2 groups were similar. Main Outcome Measures: Biochemical markers of bone resorption (serum NTX and CTX), bone formation (serum osteocalcin), and FSH were measured at baseline and after 16 weeks of treatment. Results: Serum FSH declined by 2% in the control group and by 60% in the intervention group (P < 0.0001 for the between-group difference). Despite the substantial suppression of serum FSH in the intervention group, serum NTX, CTX, and osteocalcin did not change in the intervention group, nor were any between-group differences observed. Conclusion: When gonadal steroid levels are held constant, short-mid term suppression of FSH does not affect bone turnover in men. FSH does not appear to be a significant regulator of bone metabolism in eugonadal men.
    The Journal of Clinical Endocrinology and Metabolism 03/2014; · 6.31 Impact Factor
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    ABSTRACT: Context: Anorexia nervosa (AN), a prevalent psychiatric disorder predominantly affecting women, is characterized by self-induced starvation and low body weight. Increased clinical fractures are common and most women have low bone mineral density (BMD). Previously investigated treatments have led to no or modest increases in BMD in AN. Objective: To investigate the effect of teriparatide [(hPTH-1-34), TPT], an anabolic agent, on low bone mass in women with AN. Design: Randomized, placebo-controlled Setting: Clinical Research Center Patients: 21 women with AN: 10 (mean age ± SEM: 47 ± 2.7 years) treated with TPT and 11 (47.1 ± 2.3 years) treated with placebo Interventions: TPT (20 mg SC) or placebo for six months Main outcome measures: Change in BMD of the spine and hip by dual-energy X-ray absorptiometry. Secondary outcome measures included changes in serum P1NP, CTX, sclerostin and IGF-I levels. Results: At six months, spine BMD increased significantly more with TPT [postero-anterior (PA) spine: 6.0 ± 1.4% and lateral spine: 10.5 ± 2.5%] compared to placebo (PA spine: 0.2 ± 0.7%; p<0.01 and lateral spine: -0.6 ± 1.0%; p<0.01). The results remained significant after controlling for baseline BMI, P1NP and IGF-I. Changes in femoral neck (p=0.4) and total hip (p=0.8) BMD were comparable in both groups, as were changes in weight. Serum P1NP levels increased after three months of TPT treatment and remained at this higher level at six months, whereas P1NP levels were unchanged in the placebo group (p=0.02). TPT was well tolerated by all subjects. Conclusions: This study demonstrates that TPT administration increases spine BMD substantially after only six months of therapy in women with AN.
    The Journal of Clinical Endocrinology and Metabolism 01/2014; · 6.31 Impact Factor
  • New England Journal of Medicine 12/2013; 369(25):2457. · 54.42 Impact Factor
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    ABSTRACT: Current approaches to diagnosing testosterone deficiency do not consider the physiological consequences of various testosterone levels or whether deficiencies of testosterone, estradiol, or both account for clinical manifestations. We provided 198 healthy men 20 to 50 years of age with goserelin acetate (to suppress endogenous testosterone and estradiol) and randomly assigned them to receive a placebo gel or 1.25 g, 2.5 g, 5 g, or 10 g of testosterone gel daily for 16 weeks. Another 202 healthy men received goserelin acetate, placebo gel or testosterone gel, and anastrozole (to suppress the conversion of testosterone to estradiol). Changes in the percentage of body fat and in lean mass were the primary outcomes. Subcutaneous- and intraabdominal-fat areas, thigh-muscle area and strength, and sexual function were also assessed. The percentage of body fat increased in groups receiving placebo or 1.25 g or 2.5 g of testosterone daily without anastrozole (mean testosterone level, 44±13 ng per deciliter, 191±78 ng per deciliter, and 337±173 ng per deciliter, respectively). Lean mass and thigh-muscle area decreased in men receiving placebo and in those receiving 1.25 g of testosterone daily without anastrozole. Leg-press strength fell only with placebo administration. In general, sexual desire declined as the testosterone dose was reduced. The amount of testosterone required to maintain lean mass, fat mass, strength, and sexual function varied widely in men. Androgen deficiency accounted for decreases in lean mass, muscle size, and strength; estrogen deficiency primarily accounted for increases in body fat; and both contributed to the decline in sexual function. Our findings support changes in the approach to evaluation and management of hypogonadism in men. (Funded by the National Institutes of Health and others; ClinicalTrials.gov number, NCT00114114.).
    New England Journal of Medicine 09/2013; 369(11):1011-22. · 54.42 Impact Factor
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    ABSTRACT: Context:Concern has been raised that medications that block serotonin reuptake may affect bone metabolism, resulting in bone loss.Objective:The aim of the study was to compare annual bone mineral density (BMD) changes among new users of selective serotonin reuptake inhibitors (SSRIs), new users of tricyclic antidepressants (TCAs), and nonusers of antidepressant medications.Design and Setting:We conducted a prospective cohort study at five clinical centers in the United States.Participants:The study included 1972 community-dwelling women, aged 42 years and older, enrolled in the Study of Women's Health Across the Nation (SWAN).Exposure:The use of antidepressant medications was assessed by interview and verified from medication containers at annual visits. Subjects were categorized as nonusers (no SSRI or TCA use at any examination), SSRI users (initiated SSRI use after the baseline SWAN visit), or TCA users (initiated TCA use after the baseline visit), using a computerized dictionary to categorize type of medication.Main Outcome Measures:BMD at the lumbar spine, total hip, and femoral neck was measured using dual-energy x-ray absorptiometry at annual visits.Results:BMD was compared among 311 new users of SSRIs, 71 new users of TCAs, and 1590 nonusers. After adjustment for potential confounders, including age, race, body mass index, menopausal status, and hormone therapy use, mean lumbar spine BMD decreased on average 0.68% per year in nonusers, 0.63% per year in SSRI users (P = .37 for comparison to nonusers), and 0.40% per year in TCA users (P = .16 for comparison to nonusers). At the total hip and femoral neck, there was also no evidence that SSRI or TCA users had an increased rate of bone loss compared with nonusers. Results were similar in subgroups of women stratified by the Center for Epidemiologic Studies Depression Scale (<16 vs ≥16).Conclusions:In this cohort of middle-aged women, use of SSRIs and TCAs was not associated with an increased rate of bone loss at the spine, total hip, or femoral neck.
    The Journal of Clinical Endocrinology and Metabolism 09/2013; · 6.31 Impact Factor
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    ABSTRACT: Several studies, using dual-energy x-ray absorptiometry (DXA), have reported substantial bone loss after bariatric surgery. However, profound weight loss may cause artifactual changes in DXA areal bone mineral density (aBMD) results. Assessment of volumetric bone mineral density (vBMD) by quantitative computed tomography (QCT) may be less susceptible to such artifacts. We assessed changes in BMD of the lumbar spine and proximal femur prospectively for 1 year using DXA and QCT in 30 morbidly obese adults undergoing Roux-en-Y gastric bypass surgery and 20 obese non-surgical controls. At one year, subjects who underwent gastric bypass surgery lost 37 ± 2 kg compared with 3 ± 2 kg lost in the non-surgical controls (p < 0.0001). Spine BMD declined more in the surgical group than in the non-surgical group whether assessed by DXA (-3.3 vs. -1.1%, p = 0.034) or by QCT (-3.4 vs. 0.2%, p = 0.010). Total hip and femoral neck aBMD declined significantly in the surgical group when assessed by DXA (-8.9 vs. -1.1%, p < 0.0001 for the total hip and -6.1 vs. -2.0%, p = 0.002 for the femoral neck), but no changes in hip vBMD were noted using QCT. Within the surgical group, serum P1NP and CTX levels increased by 82 ± 10% and by 220 ± 22%, respectively, by 6 months and remained elevated over 12 months (p < 0.0001 for all). Serum calcium, vitamin D, and PTH levels remained stable in both groups. We conclude that moderate vertebral bone loss occurs in the first year after gastric bypass surgery. However, striking declines in DXA aBMD at the proximal femur were not confirmed with QCT vBMD measurements. These discordant results suggest that artifacts induced by large changes in body weight after bariatric surgery affect DXA and/or QCT measurements of bone, particularly at the hip.
    Journal of bone and mineral research: the official journal of the American Society for Bone and Mineral Research 08/2013; · 6.04 Impact Factor
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    ABSTRACT: Objective.To characterize changes in bone resorption in relation to the final menstrual period (FMP), reproductive hormones, body mass index (BMI), and ethnicity.Methods.Urinary type I collagen N-telopeptide (NTX), estradiol, and FSH levels were measured annually for up to 8 years spanning the menopause transition in 918 African-American, Chinese, Japanese, or Caucasian women.Results.Urinary NTX began to increase sharply about 2 years before the FMP, reaching its peak level about 1-1.5 years after the FMP. NTX levels declined modestly from 2-6 years after the FMP but remained about 20% higher than before the menopause transition. The sharp rise in FSH occurred in conjunction with a sharp decline in estradiol and shortly after FSH levels began increasing rapidly. The mean increase in urinary NTX across the menopause transition was greatest in women with BMI's <25 kg/m(2) and smallest in women with BMI's >30 kg/m(2). Increases in NTX were greatest in Japanese women and smallest in African-Americans. These differences were attenuated, but not eliminated, when analyses were adjusted for covariates, particularly BMI.Summary.During the menopause transition a decline in ovarian function beginning about 2 years before the FMP is followed by an increase in bone resorption and subsequently by bone loss. The magnitude of the increase in bone resorption is inversely associated with BMI. Ethnic differences in changes in bone resorption are attenuated, but not eliminated, by adjustment for BMI. Ethnic differences in BMI, and corresponding ethnic differences in bone resorption, appear to account for much of the ethnic variation in peri-menopausal bone loss.
    The Journal of Clinical Endocrinology and Metabolism 05/2013; · 6.31 Impact Factor
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    ABSTRACT: African-American women have a lower risk of fracture than Caucasian women, and this difference is only partially explained by differences in DXA areal bone mineral density (aBMD). Little is known about racial differences in skeletal microarchitecture and the consequences for bone strength. To evaluate potential factors underlying this racial difference in fracture rates, we used high-resolution peripheral quantitative computed tomography (HR-pQCT) to assess cortical and trabecular bone microarchitecture and estimate bone strength using micro-finite element analysis in African-American (n = 100) and Caucasian (n = 173) women participating in the Study of Women's Health Across the Nation (SWAN). African-American women had larger and denser bones than Caucasians, with greater total area, aBMD, and total volumetric BMD (vBMD) at the radius and tibia metaphysis (p < 0.05 for all). African-Americans had greater trabecular vBMD at the radius, but higher cortical vBMD at the tibia. Cortical microarchitecture tended to show the most pronounced racial differences, with higher cortical area, thickness, and volumes in African-Americans at both skeletal sites (p < 0.05 for all), and lower cortical porosity in African-Americans at the tibia (p < 0.05). African-American women also had greater estimated bone stiffness and failure load at both the radius and tibia. Differences in skeletal microarchitecture and estimated stiffness and failure load persisted even after adjustment for DXA aBMD. The densitometric and microarchitectural predictors of failure load at the radius and tibia were the same in African-American and Caucasian women. In conclusion, differences in bone microarchitecture and density contribute to greater estimated bone strength in African-Americans and probably explain, at least in part, the lower fracture risk of African-American women.
    Journal of bone and mineral research: the official journal of the American Society for Bone and Mineral Research 04/2013; · 6.04 Impact Factor
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    ABSTRACT: Context:The associations of serum sex steroid and FSH levels with change of bone mineral density (BMD) across the complete menopausal transition are incompletely understood.Objective:The objective of the study was to examine the associations of annual serum levels of FSH, estradiol (E(2)), T, and SHBG with the rates of bone loss in 3 phases: pretransmenopausal [baseline to 1 year before the final menstrual period (FMP)], transmenopausal (1 year before to 2 years after the FMP), later postmenopausal (≥ 2 years after the FMP).Design:The design of the study was a repeated-measures, mixed-effects regression.Setting:This was a community-based observational study, with a 10-year follow-up.Participants:A total of 720 participants of the Study of Women's Health Across the Nation Bone Study participated in the study.Outcome Measures:Annualized lumbar spine (LS) and femoral neck (FN) BMD decline was measured.Results:The mean annual change in BMD was slowest in pretransmenopause (0.27%/year in FN) and fastest in transmenopause (2.16%/year in LS). In the pretransmenopausal phase, for every doubling of FSH level, LS BMD change was faster by -0.32%/year (P < .0001). In the transmenopausal phase, for every doubling of FSH level, LS BMD change was -0.35%/year faster (P < .0001); for every doubling of SHBG level, LS BMD change was -0.36%/year faster (P < .0001). In the later postmenopausal phase, for each doubling of the E(2) level, the LS BMD change was slower by +0.26%/year (P = .049); for each SHBG doubling, the LS BMD change was 0.21%/year slower (P = .048). The FN associations were weaker and inconsistent.Conclusions:Higher E(2) levels and lower FSH levels were associated with lower rates of LS bone loss in some but not all menopausal transition phases.
    The Journal of Clinical Endocrinology and Metabolism 02/2013; · 6.31 Impact Factor
  • Elaine W Yu, Joel S Finkelstein
    JAMA The Journal of the American Medical Association 10/2012; 308(14):1428-1429. · 29.98 Impact Factor
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    ABSTRACT: Objective: Vitamin D deficiency is highly prevalent in high-risk patient populations, but the prevalence among otherwise healthy adults is less well-defined. The goal of this study was to determine the prevalence and predictors of low 25-hydroxyvitamin D (25OHD) levels in healthy younger adults.Methods: This was a cross-sectional study of 634 healthy volunteers aged 18-50 years performed between January, 2006 and May, 2008. We measured serum 25OHD and parathyroid hormone and recorded demographic variables including age, sex, race, and use of multivitamin (MVI) supplements.Results: 39% of subjects had 25OHD ≤ 20 ng/mL and 64% had 25OHD ≤ 30 ng/mL. Predictors of lower 25OHD levels included male sex, black or Asian race, and lack of MVI use (p < 0.001 foswr all predictors). Seasonal variation in 25OHD levels was present in the overall cohort but was not observed in MVI users. Lower 25OHD levels were associated with increased risk of elevated PTH. Regression models predicted 25OHD levels ≤ 20 or ≤ 30 ng/mL with areas under the receiver operating characteristic (ROC) curves of 0.76 and 0.80, respectively.Conclusion: Low 25OHD levels are prevalent in healthy adults and may confer risk of skeletal disease. Black and Asian adults are at increased risk of deficiency and MVI use appears partially protective. Our models predicting low 25OHD levels may guide decision-making regarding whom to screen for vitamin D deficiency.
    Endocrine Practice 09/2012; · 2.49 Impact Factor
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    ABSTRACT: OBJECTIVE: Bone turnover markers (BTMs) predict fracture in older women, whereas data on younger women are lacking. To test the hypothesis that BTMs measured before and after menopause predict fracture risk, we performed a cohort study of 2,305 women. METHODS: Women attended up to nine clinic visits for an average of 7.6 ± 1.6 years; all were aged 42 to 52 years and were premenopausal or early perimenopausal at baseline. Incident fractures were self-reported. Serum osteocalcin and urinary cross-linked N-telopeptide of type I collagen (NTX) were measured at baseline. NTX was measured at each annual follow-up. Interval-censored survival models or generalized estimating equations were used to test whether baseline BTMs and changes in NTX, respectively, were associated with fracture risk. Hazard ratios (HRs) or odds ratios were calculated with 95% CIs. RESULTS: Women who experienced fractures (n = 184) had about a 10% higher baseline median NTX (34.4 vs 31.5 nanomoles of bone collagen equivalents per liter per nanomole of creatinine per liter; P = 0.001), but there was no difference in osteocalcin. A 1-SD decrease in lumbar spine bone mineral density (BMD) measured premenopausally was associated with a higher fracture risk during menopause (HR, 1.50; 95% CI, 1.28-1.68). Women with a baseline NTX greater than the median had a 45% higher risk of fracture, multivariable-adjusted (HR, 1.46; 95% CI, 1.05-2.26). The HR of fracture among women with both the lowest spine BMD (quartile 1) and the highest NTX (quartile 4) at baseline was 2.87 (95% CI, 1.61-6.01), compared with women with lower NTX and higher BMD. Women whose NTX increased more than the median had a higher risk of fracture (odds ratio, 1.51; 95% CI, 1.08-2.10). Women who had baseline NTX greater than the median experienced greater loss of spine and hip BMD. CONCLUSIONS: A higher urinary NTX excretion measured before menopause and across menopause is associated with a higher risk of fracture. Our results are consistent with the pathophysiology of transmenopausal changes in bone strength.
    Menopause (New York, N.Y.) 07/2012; · 3.08 Impact Factor
  • Elaine W Yu, Joel S Finkelstein
    JAMA The Journal of the American Medical Association 06/2012; 307(24):2591-2. · 29.98 Impact Factor
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    ABSTRACT: Context: Whether menopause-related changes in sex steroids account for midlife weight gain in women or whether weight drives changes in sex steroids remains unanswered. Objective: The objective of the study was to characterize the potential reciprocal nature of the associations between sex hormones and their binding protein with waist circumference in midlife women. Design, Setting, and Participants: The study included 1528 women (mean age 46 yr) with 9 yr of follow-up across the menopause transition from the observational Study of Women's Health Across the Nation. Main Outcome Measures: Waist circumference, SHBG, testosterone, FSH, and estradiol were measured. Results: Current waist circumference predicted future SHBG, testosterone, and FSH but not vice versa. For each sd higher current waist circumference, at the subsequent visit SHBG was lower by 0.04-0.15 sd, testosterone was higher by 0.08-0.13 sd, and log(2) FSH was lower by 0.15-0.26 sd. Estradiol results were distinct from those above, changing direction across the menopause transition. Estradiol and waist circumference were negatively associated in early menopausal transition stages and positively associated in later transition stages (for each sd higher current waist circumference, future estradiol was lower by 0.15 sd in pre- and early perimenopause and higher by 0.38 sd in late peri- and postmenopause; P for interaction <0.001). In addition, they appeared to be reciprocal, with current waist circumference associated with future estradiol and current estradiol associated with future waist circumference. However, associations in the direction of current waist circumference predicting future estradiol levels were of considerably larger magnitude than the reverse. Conclusions: These Study of Women's Health Across the Nation data suggest that the predominant temporal sequence is that weight gain leads to changes in sex steroids rather than vice versa.
    The Journal of Clinical Endocrinology and Metabolism 06/2012; 97(9):E1695-704. · 6.31 Impact Factor
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    ABSTRACT: Fibroblast growth factor 23 is a phosphate- and vitamin D-regulating hormone. The objective of this study was to determine the effect of ergocalciferol administration on fibroblast growth factor 23 levels in healthy vitamin D-deficient subjects. In this 12-week trial conducted in a clinical research center, 18- to 45-year-old subjects (n=90) with 25-hydroxyvitamin D levels ≤20 ng/ml (by chemiluminescent immunoassay) were randomized to weekly ergocalciferol treatment of 50,000 international units or placebo, while consuming a self-selected diet. Changes in fibroblast growth factor 23, 25-hydroxyvitamin D (by liquid chromatography/tandem mass spectroscopy), 1,25-dihydroxyvitamin D, parathyroid hormone, and serum phosphate were measured. Mean 25-hydroxyvitamin D (P<0.0001), 1,25-dihydroxyvitamin D (P=0.01), and fibroblast growth factor 23 (P=0.003) increased in the treatment versus placebo group. In the treatment group, 25-hydroxyvitamin D increased from 18 ± 7 to 40 ± 12 ng/ml at week 4 (P<0.0001) and remained stable at 43 ± 12 ng/ml at week 12 (P<0.0001); 1,25-dihydroxyvitamin D increased from 42 ± 17 to 52 ± 18 pg/ml at week 4 (P<0.001) and then remained stable, and fibroblast growth factor 23 increased from 43 ± 17 to 60 ± 33 pg/ml at week 8 (P=0.001) and 74 ± 42 pg/ml at week 12 (P<0.0001). Urinary phosphate excretion increased within the treatment group, but parathyroid hormone and serum phosphate were unchanged. Ergocalciferol administration increases circulating fibroblast growth factor 23. When measuring fibroblast growth factor 23, concurrent 25-hydroxyvitamin D measurements should be obtained, because vitamin D deficiency may lower circulating fibroblast growth factor 23 levels.
    Clinical Journal of the American Society of Nephrology 02/2012; 7(4):624-31. · 5.07 Impact Factor
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    ABSTRACT: The objective of this study was to describe: the time of onset and offset of bone mineral density (BMD) loss relative to the date of the final menstrual period (FMP); the rate and amount of BMD decline during the 5 years before and the 5 years after the FMP; and the independent associations between age at final menstrual period (FMP), body mass index (BMI) and race/ethnicity with rates of BMD loss during this time interval. The sample included 242 African-American, 384 Caucasian, 117 Chinese and 119 Japanese women, pre- or early peri-menopausal at baseline, who had experienced their FMP and for whom an FMP date could be determined. Loess-smoothed curves showed that BMD loss began 1 year before the FMP and decelerated (but did not cease) 2 years after the FMP, at both the lumbar spine (LS) and femoral neck (FN) sites. Piece-wise, linear, mixed effects regression models demonstrated that during the 10-year observation period, at each bone site, the rates and cumulative amounts of bone loss were greatest from 1 year before through 2 years after the FMP, termed the transmenopause. Postmenopausal loss rates, those occurring between 2 and 5 years after the FMP, were less than those observed during transmenopause. Cumulative, 10-year LS BMD loss was 10.6% 7.38% was lost during the transmenopause. Cumulative FN loss was 9.1% 5.8% was lost during the transmenopause. Greater BMI and African American heritage were related to slower loss rates, while the opposite was true of Japanese and Chinese ancestry. © 2011 American Society for Bone and Mineral Research.
    Journal of bone and mineral research: the official journal of the American Society for Bone and Mineral Research 10/2011; · 6.04 Impact Factor
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    Elaine W Yu, Bijoy J Thomas, J Keenan Brown, Joel S Finkelstein
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    ABSTRACT: PURPOSE: Major alterations in body composition, such as with obesity and weight loss, have complex effects on the measurement of bone mineral density (BMD) by dual-energy x-ray absorptiometry (DXA). The effects of altered body fat on quantitative computed tomography (QCT) measurements are unknown. METHODS: We scanned a spine phantom by DXA and QCT before and after surrounding with sequential fat layers (up to 12 kg). In addition, we measured lumbar spine and proximal femur BMD by DXA and trabecular spine BMD by QCT in 13 adult volunteers before and after a simulated 7.5 kg increase in body fat. RESULTS: With the spine phantom, DXA BMD increased linearly with sequential fat layering at the normal (p < 0.01) and osteopenic (p < 0.01) levels, but QCT BMD did not change significantly. In humans, fat layering significantly reduced DXA spine BMD values (mean ± SD: -2.2 ± 3.7%, p = 0.05) and increased the variability of measurements. In contrast, fat layering increased QCT spine BMD in humans (mean ± SD: 1.5 ± 2.5%, p = 0.05). Fat layering did not change mean DXA BMD of the femoral neck or total hip in humans significantly, but measurements became less precise. Associations between baseline and fat-simulation scans were stronger for QCT of the spine (r(2)  = 0.97) than for DXA of the spine (r(2)  = 0.87), total hip (r(2)  = 0.80), or femoral neck (r(2)  = 0.75). Bland-Altman plots revealed that fat-associated errors were greater for DXA spine and hip BMD than for QCT trabecular spine BMD. CONCLUSIONS: Fat layering introduces error and decreases the reproducibility of DXA BMD spine and hip measurements in human volunteers. Although overlying fat also affects QCT BMD measurements, the error is smaller and more uniform than with DXA BMD. Caution must be used when interpreting BMD changes in humans whose body composition is changing. © 2011 American Society for Bone and Mineral Research.
    Journal of bone and mineral research: the official journal of the American Society for Bone and Mineral Research 09/2011; · 6.04 Impact Factor

Publication Stats

6k Citations
1,175.38 Total Impact Points

Institutions

  • 2013
    • Boston Children's Hospital
      Boston, Massachusetts, United States
  • 2004–2012
    • Albert Einstein College of Medicine
      • Department of Obstetrics & Gynecology & Women's Health
      New York City, New York, United States
  • 1988–2012
    • Massachusetts General Hospital
      • • Division of Endocrinology
      • • Department of Medicine
      • • Biostatistics Center
      • • Neuroendocrine Unit
      Boston, MA, United States
  • 2011
    • Kaiser Permanente
      Oakland, California, United States
  • 2005–2011
    • Harvard Medical School
      • Department of Medicine
      Boston, Massachusetts, United States
  • 2003–2010
    • Partners HealthCare
      Boston, Massachusetts, United States
  • 2003–2008
    • Brigham and Women's Hospital
      • • Center for Brain Mind Medicine
      • • Department of Medicine
      • • Division of Pharmacoepidemiology and Pharmacoeconomics
      Boston, MA, United States
  • 2002
    • University of Southern California
      Los Angeles, California, United States