Build better bones with exercise (B3E pilot trial): results of a feasibility study of a multicenter randomized controlled trial of 12 months of home exercise in older women with vertebral fracture.

We pilot-tested a trial of home exercise on individuals with osteoporosis and spine fracture. Our target enrollment was met, though it took longer than expected. Participants stayed in the study and completed the exercise program with no safety concerns. Future trials should expand the inclusion criteria and consider other changes. PURPOSE: Osteoporotic fragility fractures create a substantial human and economic burden. There have been calls for a large randomized controlled trial examining the effect of exercise on fracture incidence. The B3E pilot trial was designed to evaluate the feasibility of a large trial examining the effects of home exercise on individuals at high risk of fracture. METHODS: Community-dwelling women ≥ 65 years with radiographically confirmed vertebral compression fractures were recruited at seven sites in Canada and Australia. We randomized participants in a 1:1 ratio to a 12-month home exercise program or equal attention control group, both delivered by a physiotherapist (PT). Participants received six PT home visits in addition to monthly phone calls from the PT and a blinded research assistant. The primary feasibility outcomes of the study were recruitment rate (20 per site in 1 year), retention rate (75% completion), and intervention adherence rate (60% of weeks meeting exercise goals). Secondary outcomes included falls, fractures and adverse events. RESULTS: One hundred forty-one participants were recruited; an average of 20 per site, though most sites took longer than anticipated. Retention and adherence met the criteria for success: 92% of participants completed the study; average adherence was 66%. The intervention group did not differ significantly in the number of falls (IRR 0.97, 95% CI 0.58 to 1.63) or fragility fractures (OR 1.11, 95% CI 0.60 to 2.05) compared to the control group. There were 18 serious adverse events in the intervention group and 12 in the control group. CONCLUSION: An RCT of home exercise in women with vertebral fractures is feasible but recruitment was a challenge. Suggestions are made for the conduct of future trials.

Falls relate to vitamin D and parathyroid hormone in an Australian nursing home and hostel.

OBJECTIVES: To determine whether falling relates to serum levels of vitamin D and parathyroid hormone. DESIGN: A cross-sectional study with retrospective analysis. SETTING: An aged-care institution in Melbourne Australia. PARTICIPANTS: Ambulant nursing home and hostel residents (n = 83). MEASUREMENTS: Frequency of falling, frequency of going outdoors, use of cane or walker, age, sex, weight, type of accommodation, and duration of residence. Serum concentrations of 25-hydroxyvitamin D, 1,25-dihydroxyvitamin D, and parathyroid hormone (PTH). Plasma concentrations of albumin, calcium, phosphate, and creatinine. Use of furosemide or non-benzodiazepine anticonvulsants. RESULTS: Median age of residents was 84 years. The cohort was vitamin D deficient with a median (interquartile range) 25-hydroxyvitamin D level of 27 (18-37) nmol/L (one-third the reference range median), P < .001. The median (interquartile range) PTH of 5.2 (3.8-7.7) pmol/L exceeded the reference range median, P < .001. Residents who fell (n = 33) had lower serum 25-hydroxyvitamin D levels than other residents (medians 22 vs 29 nmol/L, P = .02) and higher serum PTH levels (medians 6.2 vs 4.8 pmol/L, P < .01). Sixty residents lived in the hostel (72%), and 41 (49%) walked without any walking aid. In a multiple logistic regression for falling, higher serum PTH remained independently associated with falling, with an odds ratio (95% confidence interval) for falling of 5.6 (1.7-18.5) per unit of the natural logarithm of serum PTH. Other terms in the regression were hostel accommodation, odds ratio .04 (.01-.25), and ability to walk without aids, odds ratio .07 (.01-.37). CONCLUSIONS: In ambulant nursing home and hostel residents, residents who fall have lower serum 25-hydroxyvitamin D and higher serum parathyroid hormone levels than other residents. The association between falling and serum PTH persists after adjustment for other variables.

Acid susceptibility of arrested enamel lesions: in situ study.

Arrested lesions are more resistant to a new cariogenic challenge, but the degree of surface rehardening needed to achieve this is unknown. The aim of this in situ study was to analyze the acid susceptibilityof newly formed and arrested enamel lesions with known arrestment period and surface microhardness. Six individuals wore an oral appliance with human enamel blocks for 3 periods: (1) 21 days of demineralization due to plaque accumulation and cariogenic challenge, 4 blocks/person (nonfluoride dentifrice); (2) 75 days of arrestment, brushing with fluoride dentifrice, 2 blocks/person; (3) 21 days of demineralization, 5 blocks/person: 1 sound block, 2 demineralized blocks and 2 demineralized and arrested blocks (nonfluoride dentifrice). After period 1, all blocks showed a dull whitish surface characteristic of active, noncavitated lesions. After arrestment, the surfaces assumed a shiny and smooth aspect. The Knoop hardness number (KHN, mean+/-SD) of the sound blocks was 307.6+/-15.0. After period 1, microhardness decreased significantly to 162.6+/-33.5 KHN (p<0.001). The microhardness of subsequently arrested lesions (279.8+/-23.1 KHN) was significantly greater than after demineralization, but lower than that of sound enamel. Arrested enamel did not show a decrease in microhardness when subjected to a new cariogenic challenge and after the same cariogenic challenge showed similar microhardness to sound enamel. The results showed that, although noncavitated lesions probably take years to reach microhardness levels like sound enamel, this does not imply that special care, in addition to the ones normally given to sound tooth surfaces, is necessary.

Urine calcium and urine sodium concentrations are not related, after adjustment for urine magnesium.

BACKGROUND AND OBJECTIVES: Urine calcium correlates with urine sodium. The aims of this study were to investigate whether the urine sodium-calcium relationship persists into old age and whether it holds after adjustment for urine magnesium. DESIGN: Cross-sectional descriptive analysis. PATIENTS: Residents of two aged care institutions (median age 84 years) who were not taking diuretics, calcium or vitamin D supplements. MEASUREMENTS: Early morning urine calcium, sodium and magnesium, plasma creatinine and serum 25-hydroxyvitamin D and parathyroid hormone. RESULTS: Urine calcium correlated with urine sodium (r = 0.29, P < 0.01) and with urine magnesium (r = 0.56, P < 0.001). After adjustment for urine magnesium, the relationship between urine sodium and urine calcium was no longer significant. Forty-five percent of the interindividual variation in urine calcium was explained by a linear model on the basis of urine magnesium and plasma creatinine. CONCLUSION: The data indicate that a correlation between urine sodium and calcium persists in very old age. However, this correlation no longer holds after adjustment for urine magnesium. Further studies examining urine calcium excretion should also consider urine magnesium.

Risk factors for secondary hyperparathyroidism in a nursing home population.

OBJECTIVE: Secondary hyperparathyroidism may cause bone loss and structural deterioration of bone and may thus be a cause of fracture in the elderly. Vitamin D deficiency, renal impairment and medications are potential causes of hyperparathyroidism and may also directly predispose to fracture. We present the first findings of an ongoing study of hip fracture, vitamin D deficiency and hyperparathyroidism in a large Australian nursing home. DESIGN: Descriptive prevalence study. PATIENTS: Two hundred and fifty-one nursing home residents were eligible for inclusion. Informed consent and successful venepuncture were obtained for 99. Residents were of median age 83 years with interquartile range (IR) 77-89 years. MEASUREMENTS: 25-Hydroxyvitamin D (25OHD), intact parathyroid hormone (PTH), creatinine and biochemistry, demographic data and current medications. RESULTS: Fifty-two per cent of 99 subjects had 25OHD below the reference range of 28-165 nmol/l and 96.5% were below the reference range mean. Those with low 25OHD had lower plasma calcium corrected for albumin than those with normal 25OHD (medians 2.34 vs 2.41 mmol/l, 95% confidence interval for the difference between medians (CI) -0.10 to -0.04 mmol/l, P = 0.0001) and higher PTH (medians 5.8 vs 3.9 pmol/l, CI 0.10-2.6 pmol/l, P = 0.0360). Twenty-eight per cent of 97 residents had PTH above the upper reference range limit of 6.5 pmol/l. Residents receiving frusemide had higher PTH than other residents (medians 6.95 vs 3.45 pmol/l, CI 1.9-4.2 pmol/l, P < 0.0001). In linear modelling, the most important predictor of the natural logarithm of PTH was daily frusemide dose, adjusted R2 (Ra2) = 31.8%, F = 39.3, P < 0.001. Creatinine and the reciprocal of 25OHD were other significant predictors with the final Ra2 = 39.4%, F = 17.7, P < 0.001. CONCLUSIONS: Vitamin D deficiency is a common risk factor for secondary hyperparathyroidism in nursing home residents despite a climate in which vitamin D nutrition is thought to be ample. However, the daily frusemide dose is a more important predictor of PTH in this population.

Relationships with serum parathyroid hormone in old institutionalized subjects.

OBJECTIVE AND BACKGROUND: Old people in residential care are at the highest risk of any group for hip fracture. This may relate to their high prevalence of hyperparathyroidism. There are few data, however, on relationships with serum parathyroid hormone (PTH) in these individuals. This study therefore examined complex associations with serum PTH in nursing home and hostel residents. DESIGN: Cross-sectional analysis. PATIENTS: One hundred and forty-three nursing home and hostel residents of median age 84 years. MEASUREMENTS: Serum PTH, 25-hydroxyvitamin D (25OHD), 1,25-dihydroxyvitamin D (1,25-(OH)2D), plasma creatinine, phosphate, calcium, albumin, Bsm-1 vitamin D receptor genotype, age, weight and use of frusemide or thiazide. RESULTS: The statistical models determined accounted for half the interindividual variation in serum PTH. Heavier weight was associated with both the prevalence of secondary hyperparathyroidism and the serum concentration of PTH. Novel interactions with serum PTH were identified between: weight and 25OHD; 25OHD and phosphate; and phosphate and thiazide diuretic use. Plasma phosphate was associated with PTH independently of calcium and 1,25-(OH)2D. There was no independent association between PTH and nuclear vitamin D receptor genotype. CONCLUSIONS: Heavier weight is associated with both the prevalence and severity of secondary hyperparathyroidism and consistent with animal models of secondary hyperparathyroidism, phosphate may relate to serum PTH independently of 1,25-(OH)2D or calcium.