Jun Iwamoto

Low-dose vitamin D prevents muscular atrophy and reduces falls and hip fractures in women after stroke: a randomized controlled trial.

OBJECTIVE Vitamin D supplementation is suggested to reduce the risk of falls among ambulatory or institutionalized elderly subjects. The present study was undertaken to address the reduced risk of falls and hip fractures in patients with long-standing stroke by vitamin D supplementation. METHODS Ninety-six elderly women with poststroke hemiplegia were followed for two years. Patients were randomly assigned to one of the two groups, and 48 patients received 1,000 IU ergocalciferol daily, and the remaining 48 received placebo. The number of falls per person and incidence of hip fractures were compared between the two groups. Strength and tissue ATPase of skeletal muscles on the nonparetic side were assessed before and after the study. RESULTS At baseline, serum 25-hydroxyvitamin D levels were in the deficient range (<10 ng/ml) in all patients; and vitamin D treatment enhanced serum 25-hydroxyvitamin D and 1,25-dihydroxyvitamin D levels. Vitamin D treatment accounted for a 59% reduction in falls (95% CI, 28-81%; p = 0.003). There were increases in the relative number and size of type II muscle fibers and improved muscle strength in the vitamin D-treated group. Hip fractures occurred in 4 of 48 placebo group and 0 in 48 vitamin D2 group during the 2-year study period (log-rank, p = 0.049). CONCLUSION Vitamin D may increase muscle strength by improving atrophy of type II muscle fibers, which may lead to decreased falls and hip fractures.

Effect of whole-body vibration exercise on lumbar bone mineral density, bone turnover, and chronic back pain in post-menopausal osteoporotic women treated with alendronate.

Background and aims: Exercise may enhance the effect of alendronate on bone mineral density (BMD) and reduce chronic back pain in elderly women with osteoporosis. The aim of this study was to determine whether whole-body vibration exercise would enhance the effect of alendronate on lumbar BMD and bone turnover, and reduce chronic back pain in post-menopausal women with osteoporosis. Methods: Fifty post-menopausal women with osteoporosis, 55–88 years of age, were randomly divided into two groups of 25 patients each: one taking alendronate (5 mg daily, ALN) and one taking alendronate plus exercise (ALN+EX). Exercise consisted of whole-body vibration using a Galileo machine (Novotec, Pforzheim, Germany), at an intensity of 20 Hz, frequency once a week, and duration of exercise 4 minutes. The study lasted 12 months. Lumbar BMD was measured by dual energy X-ray absorptiometry (Hologic QDR 1500W). Urinary cross-linked N-terminal telopeptides of type I collagen (NTX) and serum alkaline phos-phatase (ALP) levels were measured by enzyme-linked immunosorbent assay and standard laboratory techniques, respectively. Chronic back pain was evaluated by face scale score at baseline and every 6 months. Results: There were no significant differences in baseline characteristics, including age, body mass index, years since menopause, lumbar BMD, urinary NTX and serum ALP levels, or face scale score between the two groups. The increase in lumbar BMD and the reduction in urinary NTX and serum ALP levels were similar in the ALN and ALN+EX groups. However, the reduction in chronic back pain was greater in the ALN+EX group than in the ALN group. Conclusions: The results of this study suggest that whole-body vibration exercise using a Galileo machine appears to be useful in reducing chronic back pain, probably by relaxing the back muscles in post-menopausal osteoporotic women treated with alendronate.

Differential effect of treadmill exercise on three cancellous bone sites in the young growing rat

The aim of the present study was to examine cancellous bone changes induced by exercise on three different skeletal sites, the lumbar vertebra, the proximal, and the distal tibia, in the young growing rat. Forty 4-week-old female Sprague-Dawley rats were randomized into 4 groups of 10 animals each; 8 weeks exercise (8EX), 8 weeks sedentary control (8CON), 12 weeks exercise (12EX), and 12 weeks sedentary control (12CON). The exercise regimen consisted of treadmill running at 24 m/min 1 hr per day 5 days a week. After each period of exercise, the proximal and distal tibial metaphyses (PTM and DTM, respectively) and the fifth lumbar (L5) vertebral body were processed for histomorphometry of the cancellous bone (secondary spongiosa) and cortical periosteum. Eight and twelve weeks of exercise significantly increased the mineral apposition rate and bone formation rate in the PTM and DTM, and 12 weeks of exercise significantly increased the labeled perimeter in the DTM, compared with the age-matched controls. Eight and twelve weeks of exercise significantly increased cancellous bone volume in the PTM (mean +/- standard deviation, 8EX; 19.1 +/- 2.9% vs 8CON; 14.3 +/- 3.1%, P < 0.05 and 12EX; 18.8 +/- 3.5% vs 12CON; 15.2 +/- 3.3%, P < 0.05), and 12 weeks exercise significantly increased cancellous bone volume in the DTM, compared with age-matched control (12EX; 32.5 +/- 7.7%, 12CON; 22.2 +/- 4.8%, P < 0.05). The increase in cancellous bone volume by 12 weeks exercise was higher in the DTM than that in the PTM (43.4% and 24.0%, respectively). On the other hand, the exercise did not significantly affect cancellous bone volume and bone formation in the L5 vertebral body, although the cortical periosteal bone formation rate and the L5 vertebral bone mass were increased. These findings suggest that cancellous bone adaptation to treadmill exercise is site specific, and the effect may be influenced by factors such as mechanical loading and metaphyseal bone architecture in the young growing rat.

Effect of walking exercise on bone metabolism in postmenopausal women with osteopenia/osteoporosis

The purpose of this prospective study was to determine whether moderate walking exercise in postmenopausal women with osteopenia/osteoporosis would affect bone metabolism. Fifty postmenopausal women, aged 49–75 years, with osteopenia/osteoporosis were recruited: 32 women entered the exercise program (the exercise group) and 18 served as controls (the control group). The exercise consisted of daily outdoor walking, the intensity of which was 50% of maximum oxygen consumption, with a duration of at least 1 h with more than 8000 steps, at a frequency of 4 days a week, over a 12-month period. Lumbar (L2–L4) bone mineral density (BMD) was measured at the baseline and every 6 months with dual-energy X-ray absorptiometry (DXA) in both groups. Serum bone-specific alkaline phosphatase (BAP) and urinary cross-linked N-terminal telopeptides of type I collagen (NTX) levels were measured at baseline and at months 1, 3, 6, 9, and 12 by EIA and ELISA, respectively, in the exercise group, and urinary NTX level was measured at the baseline and every 6 months in the control group. There were no significant differences in baseline characteristics including age, height, body weight, bone mass index, years since menopause, lumbar BMD, and urinary NTX level between the two groups. Although no significant changes were observed in lumbar BMD and the urinary NTX level in the control group, lumbar BMD in the exercise group was increased as compared with the control group, but was sustained from the baseline. In the exercise group, the urinary NTX level rapidly responded to walking exercise from month 3, and this reduction was sustained until month 12, followed by reduction in the serum BAP level. A moderately negative correlation was found between the percent change in the urinary NTX level at month 3 and that in lumbar BMD at month 12 in the exercise group. This study clearly demonstrates that the mechanism for the positive response of lumbar BMD to moderate walking exercise in postmenopausal women with osteopenia/osteoporosis appears to be the suppression of bone turnover, and that an early change in the urinary NTX level may be useful to predict the long-term response of increasing lumbar BMD to exercise, although its efficacy for lumbar BMD may be quite modest.

Risedronate and ergocalciferol prevent hip fracture in elderly men with parkinson disease

BACKGROUND There is a high incidence of hip fractures in patients with Parkinson disease (PD). Bone mineral density (BMD) is decreased in patients with PD, correlating with the immobilization-induced bone resorption and hypovitaminosis D with compensatory hyperparathyroidism. OBJECTIVE To evaluate the effectiveness of risedronate, an inhibitor of bone resorption, on osteoporosis and the risk of hip fractures in elderly men with PD. METHODS This was a 2-year, randomized, double-blind, placebo-controlled trial. In a prospective study of patients with PD, 121 patients received a daily dose of 2.5 mg risedronate and vitamin D2 1,000 IU for 2 years, and the remaining 121 received placebo and vitamin D2 1,000 IU. Incidence of hip fractures was compared between the two groups. RESULTS Nine patients sustained hip fractures in the placebo group, and three hip fractures occurred in the risedronate group. The relative risk of a hip fracture in the risedronate group vs the placebo group was 0.33 (95% CI, 0.09 to 1.20). BMD increased by 2.2% in the risedronate group and decreased by 2.9% in the placebo group (p < 0.0001). Urinary deoxypyridinoline, a bone resorption marker, decreased by 46.7% in the risedronate group and by 33.0% in the placebo group. CONCLUSION Treatment with risedronate and vitamin D2 increases bone mineral density in elderly men with Parkinson disease and reduces the risk of hip fractures.

Relationship Between Radiographic Abnormalities of Lumbar Spine and Incidence of Low Back Pain in High School and College Football Players A Prospective Study

Background Low back pain is a common presenting symptom among players of American football. In Japan, however, skeletal disorders in football players, including low back problems, have been rarely studied, and management to prevent skeletal disorders has not been established. Study Design An epidemiological study with prospective observation. Methods The authors analyzed the relationship between lumbar spine abnormalities viewed through radiographs taken during the preparticipation physical examination, and the incidence of low back pain during a 1-year period in 171 high school and 742 college football players. Abnormalities assessed were spondylolysis, disc space narrowing, spinal instability, Schmorls node, balloon disc, and spina bifida occulta. Results High school players with spondylolysis had a higher incidence of low back pain (79.8%) than those with no abnormal radiographic results (37.1%). College players with spondylolysis, disc space narrowing, and spinal instability had a higher incidence of low back pain (80.5%, 59.8%, and 53.5%, respectively) than those with no abnormal radiographs (32.1%), and college players with spondylolysis had a higher incidence of low back pain than those with disc space narrowing and spinal instability. Conclusions The results of the present study suggest that an abnormality such as spondylolysis is the most significant risk factor for low back pain in high school and college football players, and that disc space narrowing and spinal instability are also significant risk factors for low back pain in athletes with greater athletic activity such as college football players.

Risedronate therapy for prevention of hip fracture after stroke in elderly women

BACKGROUND There is a high incidence of hip fractures in patients with hemiplegic stroke. Bone mineral density (BMD) is decreased in the hemiplegic side in patients after stroke, correlating with the degree of paralysis and of hypovitaminosis D. OBJECTIVE To evaluate the efficacy of risedronate in reducing the severity of osteoporosis and in decreasing the risk of hip fractures in elderly women following an acute stroke. METHODS This was a 12-month, randomized, double blind, placebo-controlled trial. In a prospective study of stroke patients, 187 patients received a daily dose of 2.5 mg risedronate for 12 months, and the remaining 187 received placebo. Incidence of hip fracture was compared between the two groups at the endpoint of the study. RESULTS Seven patients sustained hip fractures on the hemiplegic side in the placebo group, and one hip fracture occurred in the risedronate group (p = 0.0360; OR = 7.0). BMD increased by 1.5% and decreased by 4.9% in the risedronate group and placebo group (p < 0.0001). Urinary deoxypyridinoline, a bone resorption marker, decreased by 53.4% in the risedronate group and increased by 35.8% in the placebo group. CONCLUSION Treatment with risedronate increases bone mineral density in elderly women following an acute stroke and prevents hip fractures.

Amelioration of osteoporosis and hypovitaminosis D by sunlight exposure in hospitalized, elderly women with Alzheimer's disease: a randomized controlled trial

The JBMR editors express a note of concern that a substantial amount of the text of Sato et al., Amelioration of Osteoporosis and Hypovitaminosis D by Sunlight Exposure in Hospitalized Elderly Women With Alzheimers Disease: A Randomized Controlled Trial. J Bone Miner Res. 2005;20(8): 1327–1333 (DOI: 10.1359/JBMR.050402) is duplicated in Sato et al., Amelioration of osteoporosis and hypovitaminosis D by sunlight exposure in Parkinsons disease (Parkinsonism Relat Disord. 2011;17(1):22‐26 (DOI:10.1016/j.parkreldis.2010.10.008).

Risk factors for hip fracture among elderly patients with Alzheimer's disease

Incidence of hip fracture among patients with Alzheimers disease (AD), especially in elderly patients, is high. To analyze risk factors of hip fracture, we prospectively studied a cohort of elderly female patients with AD. Subjects studied were 225 female patients with AD, and the average age was 76 years old. At baseline, we recorded body mass index (BMI), a score of Mini-Mental State Examination (MMSE) and bone mineral density (BMD), and measured serum concentrations of ionized calcium, intact parathyroid hormone (PTH), pyridinoline cross-linked carboxyterminal telopeptide of type I collagen (ICTP), intact bone Gla protein (BGP), 25-hydroxyvitamin (25-OHD) and 1, 25-dihydroxyvitamin D (1, 25-[OH]2D). The patients were followed for 2 years. During the 2-year study, hip fractures occurred in 29 patients. We compared baseline variables between the 29 patients with and 176 patients without hip fracture. AD patients with lower BMD, low concentrations of serum ionized calcium and 25-OHD (mean 3.0 ng/ml) with compensatory hyperparathyroidism were found to have an increased risk of hip fracture. Also, concentrations of serum ICTP and BGP were higher in the fracture group than in the nonfracture group. Elderly female AD patients with low BMD and serum 25-OHD concentrations <5 ng/ml with secondary hyperparathyroidism have a high risk of hip fracture, and the risk may be reduced by vitamin D supplementation.

Relationship between radiographic abnormalities of lumbar spine and incidence of low back pain in high school rugby players: a prospective study

The purpose of this study was to examine the relationship between prevalent radiographic abnormalities of the lumbar spine and the incidence of low back pain in high school rugby players. Three hundred and twenty‐seven incoming high school rugby players (15–16 years of age) were recruited between 1986 and 1994. All of them underwent athletic physical examination before participation in high school athletics. The relationship between prevalent radiographic abnormalities of the lumbar spine in the pre‐participation athletic physical examination and the incidence of low back pain during a 1‐year period after the start of participation in athletics was analyzed. Radiographic abnormalities assessed were spondylolysis, disc space narrowing, spinal instability, Schmorls node, balloon disc, and spina bifida occulta. The frequency of respective radiographic abnormalities was 15.6%, 13.1%, 32.7%, 14.1%, 11.6%, and 30.6%. Two hundred and forty‐three players (74.3%) had at least one of these radiographic abnormalities. The incidence of low back pain was 44.0% in players with no such radiographic abnormalities and 41.2% in those with at least one radiographic abnormality. The incidence of low back pain in players with the respective radiographic abnormalities was 72.5%, 46.5%, 46.7%, 39.1%, 34.2%, and 41.0%, and only players with spondylolysis had a significantly higher incidence of low back pain than those with no radiographic abnormalities. This study shows that a radiographic abnormality, specifically spondylolysis, is a significant radiological risk factor for low back pain in high school rugby players.