Bone Loading and the Spine: Total Body and Lumbar Bone Mineral Density in Elite Male Gymnasts, Swimmers and Controls

528 (BC) on chemotherapy and adjuvant therapy, fractures occur at relatively normal bone density. Methods: We reviewed two single site retrospective studies, a multicenter randomized controlled trial and a prospective study of postmenopausal women with breast cancer. Results: 1) A single center study with a 6 year follow up, evaluated 422 newly diagnosed women with BC, aged 42 to 75 years. Seventy-nine (18%) women sustained fractures, often within 4 years of cancer diagnosis. The mean age was 62 ± 8 years, 13% of fractures were hip fractures, and the mean hip T-score was −1.3 ± 0.6; 2) Another single center retrospective study recently identified during a median follow-up of 4.9 years, in 17,110 women with BMD testing (658 BC patients), 1193 women experienced an osteoporotic fracture (62 in BC and 1131 in no-BC groups). Among all fractured women, BMD are similar between BC and no-BC groups. BC patients who experienced an osteoporotic fracture tend to have less-advanced BC, lower rates of chemotherapy treatment, and higher rates of tamoxifen treatment; 3) In the Austrian Breast Cancer Study Group (ABCSG) multi-center study, the effect of denosumab on fractures was assessed. The median patient age was 64 years (range 38–91). After 3 years, fractures occurred equally (10%) in women with BC in the control group (n = 1709) with normal or low bone mass (not osteoporosis). Denosumab reduced fracture risk by 50%; 4) Within the Women’s Health Initiative Bone Density Study, we evaluated 211 women presenting with a prior diagnosis of breast cancer, and 566 women with other cancers, while 10,097 cases were cancer free. Women with low bone mass and osteoporosis were more likely to sustain fractures (p = 0.02), with the majority of fractures being seen in women with low bone mass (58%). The FRAX risk calculation was greater in women with fractures, the mean 10 year-risk of major fractures was 15.40 ± 9.77% and the risk for hip fracture was 4.3 ± 5.46 %. Conclusion: The relation between BMD and fracture risk in women with BC varies according to the stage of treatment. This raises the possibility of bone quality alterations in women on chemotherapy or adjuvant therapy, and a return to an age-related pattern of bone loss in cancer survivors.

Abstracts

Fig. 1. Total body BMD Z-scores (+SD) for each group by age.

BONE LOADING AND THE SPINE: TOTAL BODY AND LUMBAR BONE MINERAL DENSITY IN ELITE MALE GYMNASTS, SWIMMERS AND CONTROLS Lisa Gannon, Karen Hind; Institute for Sport, Physical Activity and Leisure, Centre for Sports Performance, Carnegie Faculty, Leeds Beckett University, UK

Background: Elite gymnastics and swimming demand long hours of training, involving contrasting magnitudes of forces on the skeleton. Although gravitational skeletal loading is associated with positive increases in total bone mineral density (BMD), little is known about the effect of such training on sitespecific BMD in young athletic males at different ages across the development of peak bone mass. The purpose of the study was to explore the bone mineral properties of young male athletes involved in high impact (gymnastics) versus low impact (swimming) sports. Methods: 98 males, aged 6–24yrs: gymnasts (n = 38) swimmers (n = 23) controls (n = 37) completed the bone-specific physical activity questionnaire (BPAQ) and a 7 day diet and exercise diary. Dual energy X-ray absorptiometry (iDXA, GE Lunar) determined bone mineral properties of the total body and lumbar spine (L1-L4), with the latter scan also determining body composition. Participants were divided into three groups: juniors (pre-pubescent), adolescents (11–16 yrs) and seniors (18–25 yrs). Results: Gymnasts in all three groups had significantly higher BPAQ scores than swimmers and controls (p < 0.001). Age-matched senior gymnasts had significantly higher lumbar spine L1-L4 BMD (g.cm2) and Z-scores than swimmers (p = 0.004) and controls (p = 0.012). BPAQ total score was positively associated with lumbar spine BMD Z-score in adolescents (R2 = 0.440), and BMD g/cm2 in seniors (R2 = 0.591, all p < 0.05), as was lean body mass with total body (less head) bone mineral content (BMC) in juniors and adolescents (R2 = 0.770, p < 0.001) and total body BMD in seniors (R2 = 0.632, p = 0.05) regardless of sport participation. Conclusion: Gravitational loading in gymnastics appears to elucidate benefits for accruing peak bone mass, particularly in the male spine. This supports the role of weight-bearing exercise during growth and, if BMD is maintained, may reduce osteoporosis risk in later life. Swimmers may benefit from including impact loading exercise in their training programme.

Supported by the Carnegie Research Fund.

Fig. 2. L1-L4 Z-scores (+ SD) for each group by age. Junior – gymnasts (n = 11) swimmers (n = 5) controls (n = 11) Adolescents – gymnasts (n = 13) swimmers (n = 12) controls (n = 14) Seniors – gymnasts (n = 14) swimmers (n = 6) controls (n = 12)

BONE MINERAL DENSITY AND TRABECULAR BONE SCORE IN UKRAINIAN WOMEN WITH OBESITY Vladyslav Povoroznyuk, Nataliia Dzerovych, Larysa Martynyuk, Iryna Syzonenko; D.F. Chebotarev Institute of Gerontology NAMS Ukraine,

Kyiv, Ukraine The aim of this study was to evaluate the bone mineral density (BMD), trabecular bone score (TBS) in the Ukrainian women with obesity. Materials and Methods: 1025 women aged 40–89 years (mean age – 62.7 ± 9.7 yrs; mean height – 161.4 ± 6.2 cm; mean weight – 73.9 ± 13.8 kg, body mass index – 28.4 ± 5.1 kg/m2) were examined. The women were divided into the following groups depending on their body mass index: A – 360 women with obesity, BMI ≥ 30 kg/m2 (mean age – 64.0 ± 8.9 yrs; mean height – 160.7 ± 5.9 cm; mean weight – 87.6 ± 10.5 kg,body mass index – 33.9 ± 3.5 kg/m2),B – 665 women without obesity, BMI < 30 kg/m2 (mean age – 62.0 ± 10.0 yrs; mean height – 161.7 ± 6.4 cm; mean weight – 66.4 ± 8.9 kg, body mass index – 25.4 ± 2.8 kg/m2). BMD was measured by the DXA method (Prodigy, GEHC Lunar, Madison, WI, USA). TBS (L1-L4) was assessed by means of TBS iNsight® software installed on our DXA machine (Med-Imaps, Pessac, France). The study results are presented in the following manner: M ± SD. We performed an one-way ANOVA test, multiple regression and correlation analysis. Significance was set at p < 0.05. “Statistika 6.0” © StatSoft, Inc. was used for data processing purposes. Results: We have found that obese women have a significantly higher BMD of lumbar spine (A – 1.114 ± 0.197 g/cm2, B – 0.994 ± 0.194 g/cm2), femoral neck (A – 0.873 ± 0.137 g/cm2, B – 0.822 ± 0.136 g/cm2), total body (A – 1.123 ± 0.108 g/cm2, B – 1.037 ± 0.111 g/cm2) and ultradistal forearm (A – 0.429 ± 0.087 g/cm2, B – 0.371 ± 0.082 g/cm2) in comparison with women without obesity.When analyzing

Journal of Clinical Densitometry: Assessment & Management of Musculoskeletal Health

Volume 19, 2016