Catherine J. Bacon

Randomized Controlled Trial of Calcium Supplementation in Healthy, Nonosteoporotic, Older Men

BACKGROUND There is no consistent evidence, to our knowledge, that calcium supplementation affects bone mineral density (BMD) in men, despite male osteoporosis being a common clinical problem. METHODS To determine the effects of calcium supplementation (600 mg/d, 1200 mg/d, or placebo) on BMD in men, we conducted a double-blind, randomized controlled trial for a 2-year period at an academic clinical research center. A total of 323 healthy men at least 40 years old (mean age, 57 years) were recruited by newspaper advertisement. Complete follow-up was achieved in 96% of subjects. RESULTS The BMD increased at all sites in the group receiving calcium, 1200 mg/d, by 1% to 1.5% more than those receiving placebo. The results for the group receiving calcium, 600 mg/d, were not different from the placebo group at any BMD site. There was no interaction between the BMD treatment effect and either age or dietary calcium intake. There were dosage-related, sustained decreases in serum parathyroid hormone (P < .001), total alkaline phosphatase activity (P = .01), and procollagen type 1 N-terminal propeptide (P < .001) amounting to 25%, 8%, and 20%, respectively, in the group receiving calcium, 1200 mg/d, at 2 years. Tooth loss, constipation, and cramps were unaffected by calcium supplementation, falls tended to be less frequent in the group receiving calcium, 1200 mg/d, but vascular events tended to be more common in the groups receiving calcium vs the group receiving placebo. CONCLUSION Calcium, 1200 mg/d, has effects on BMD in men comparable with those found in postmenopausal women but a dosage of 600 mg/d is ineffective for treating BMD. TRIAL REGISTRATION actr.org.au Identifier: 012605000274673.

Vitamin D insufficiency and health outcomes over 5 y in older women

BACKGROUND Vitamin D insufficiency was shown to be associated with adverse musculoskeletal and nonskeletal outcomes in numerous observational studies. However, some studies did not control for confounding factors such as age or seasonal variation of 25-hydroxyvitamin D [25(OH)D]. OBJECTIVE We sought to determine the effect of vitamin D status on health outcomes. DESIGN Healthy community-dwelling women (n = 1471) with a mean age of 74 y were followed in a 5-y trial of calcium supplementation. 25(OH)D was measured at baseline in all women. Skeletal and nonskeletal outcomes were evaluated according to seasonally adjusted vitamin D status at baseline. RESULTS Fifty percent of women had a seasonally adjusted 25(OH)D concentration <50 nmol/L. These women were significantly older, heavier, and less physically active and had more comorbidities than women with a seasonally adjusted 25(OH)D concentration > or =50 nmol/L. Women with a seasonally adjusted 25(OH)D concentration <50 nmol/L had an increased incidence of stroke and cardiovascular events that did not persist after adjustment for between-group differences in age or comorbidities. Women with a seasonally adjusted 25(OH)D concentration <50 nmol/L were not at increased risk of adverse consequences for any musculoskeletal outcome, including fracture, falls, bone density, or grip strength or any nonskeletal outcomes, including death, myocardial infarction, cancer, heart failure, diabetes, or adverse changes in blood pressure, weight, body composition, cholesterol, or glucose. CONCLUSIONS Vitamin D insufficiency is more common in older, frailer women. Community-dwelling older women with a seasonally adjusted 25(OH)D concentration <50 nmol/L were not at risk of adverse outcomes over 5 y after control for comorbidities. Randomized placebo-controlled trials are needed to determine whether vitamin D supplementation in individuals with vitamin D insufficiency influences health outcomes. This trial was registered at www.anzctr.org.au as ACTRN 012605000242628.

Effects of calcium supplementation on lipids, blood pressure, and body composition in healthy older men: a randomized controlled trial

BACKGROUND Calcium supplementation has been suggested to have beneficial effects on serum lipids, blood pressure, and body weight, but these possibilities have not been rigorously assessed in men. OBJECTIVE This study evaluated the effect of calcium supplementation on the change in the ratio of HDL to LDL cholesterol (primary endpoint) and on changes in cholesterol fractions, triglycerides, blood pressure, and body composition (secondary endpoints). DESIGN We carried out a randomized controlled trial of calcium supplementation in 323 generally healthy men over a period of 2 y. Subjects were randomly assigned to take placebo, 600 mg Ca/d, or 1200 mg Ca/d. RESULTS There was no significant treatment effect on the ratio of HDL to LDL cholesterol (P = 0.47) nor on weight, fat mass, lean mass, triglycerides, or total, LDL, or HDL cholesterol (P > 0.28 for all). There were downward trends in systolic and diastolic blood pressures within the calcium-supplemented groups, but there were no significant treatment effects over the whole trial period (P > 0.60). In a post hoc analysis of those with baseline calcium intakes below the median value (785 mg/d), blood pressures showed borderline treatment effects (P = 0.05-0.06 for changes at 2 y in those who received 1200 mg Ca/d compared with placebo: systolic, -4.2 mm Hg; diastolic, -3.3 mm Hg). Low magnesium intake showed a similar interaction. No treatment effects on weight or body composition were found. CONCLUSIONS These data do not show significant effects of calcium supplementation on serum lipids or body composition. Calcium supplementation in those with low dietary intakes may benefit blood pressure control. This trial was registered with the Australian Clinical Trials Registry as ACTRN 012605000274673.

Very high rates of vitamin D insufficiency in women of child-bearing age living in Beijing and Hong Kong.

We aimed to describe the vitamin D status of young women living in two Chinese cities in the spring--Beijing in the north (latitude 39 degrees north) and Hong Kong (latitude 22 degrees north) in the south. We also examined the relationship between serum 25-hydroxyvitamin D and parathyroid hormone (PTH) concentrations to determine a threshold for serum 25-hydroxyvitamin D above which there is no further suppression of PTH. Finally, we examined whether dietary Ca intake influences this relationship. Non-pregnant women aged 18-40 years (n 441) were recruited between February and June. Fasting blood was collected and dietary intakes were assessed using 5 d food records. Mean serum 25-hydroxyvitamin D concentration was lower in Beijing than Hong Kong women (29 v. 34 nmol/l; P < 0.001). Vitamin D deficiency (< or = 25 nmol/l) was indicated in 40% of Beijing and 18% of Hong Kong women, and over 90% of women in both cities were insufficient (< or = 50 nmol/l). Mean Ca and vitamin D intakes were 478 mg/d and 2.0 microg/d, respectively. The relationship between 25-hydroxyvitamin D concentration and PTH was linear throughout the range with a slope of -0.36 (different from 0; P < 0.001; R 0.26), with no apparent threshold. There was no influence of Ca intake on the relationship between 25-hydroxyvitamin D and PTH concentration. Vitamin D deficiency is common and insufficiency is very common in non-pregnant women in Hong Kong and Beijing during spring. Serum 25-hydroxyvitamin D was inversely associated with PTH with no apparent threshold. Strategies such as vitamin D fortification or supplementation may be required.

Vitamin D status of Māori and non-Māori octogenarians in New Zealand: a cohort study (LiLACS NZ)

BACKGROUND AND OBJECTIVES This study assessed vitamin D status and its determinants in a cohort of octogenarians living within New Zealands Bay of Plenty and Lakes Districts. METHODS AND STUDY DESIGN Serum 25- hydroxyvitamin D [25(OH)D] concentration was measured in 209 Māori (aged 80-90 years) and 357 non-Māori (85 years), along with demographic, lifestyle, supplement use and other health data. RESULTS Mean [95% CI] 25(OH)D concentration was 69 [67 to 72] nmol/L, with 15% >100 nmol/L and 6 individuals >150 nmol/L. Concentrations in Māori (59 [55 to 62] 4 nmol/L) were lower than in non-Māori (75 [72 to 78] nmol/L; p<0.001), a difference maintained when adjusted for day-of-year measured. Vitamin D supplementation was reported by 98 participants (18%): including a greater proportion of women (24%) than men (11%; p<0.001) and of non-Māori (24%) than Māori (7%; p<0.001). Of those taking vitamin D, 49% took high oral doses (>=25 μg/day or equivalent) and five individuals took >50 μg/day. Vitamin D supplement use strongly and independently predicted seasonally- adjusted 25(OH)D concentration and was associated with 28 nmol/L higher levels than non-use. Other predictors included Māori ethnicity (10 nmol/L lower concentration than for non-Māori), and female gender (11 nmol/L lower). CONCLUSIONS Vitamin D status in New Zealand octogenarians appears higher than previously reported, particularly in non-Māori compared to Māori. Prescribed and non-prescribed oral vitamin D supplementation is prevalent in this group and a strong indicator of vitamin D status.

The Effect of Cervical Spine Manipulation on Postural Sway in Patients With Nonspecific Neck Pain

OBJECTIVE This crossover study aimed to determine whether a single high-velocity, low-amplitude manipulation of the cervical spine would affect postural sway in adults with nonspecific neck pain. METHODS Ten participants received, in random order, 7 days apart, a high-velocity, low-amplitude manipulation applied to a dysfunctional spinal segment and a passive head-movement control. Four parameters of postural sway were measured before, immediately after, and at 5 and 10 minutes after each procedure. RESULTS Results showed no differences between interventions in change in any of the parameters. When changes before and immediately after each procedure were analyzed separately, only the control showed a significant change in the length of center of pressure path (an increase from median, 118 mm; interquartlie range, 93-137 mm to an increase to 132 mm; 112-147; P = .02). CONCLUSION This study failed to show evidence that single manipulation of the cervical spine influenced postural sway. Given the ability of the postural control system to reweight the hierarchy of sensory information to compensate for inadequacies in any 1 component, it is possible that any improvements in the mechanisms controlling postural sway elicited by the manipulative intervention may have been concealed.

Falls and depression in octogenarians - life and living in advanced age: a cohort study in New Zealand

INTRODUCTION Falls and injury have the most devastating consequences for very old people. Depression may be a significant cause and consequence of falls. AIM To examine the association between falls and depression in octogenarians. METHODS LiLACS NZ (Life and Living in Advanced Age: A Cohort Study in New Zealand), cohort study data of Māori (aged 80-90 years, 11-year age band) and non-Māori (aged 85 years, 1-year age band) followed for 3 years was used to describe the incidence and prevalence of falls and depression. Falls by self-report were accumulated over 3 years. Geriatric depression score (GDS) was ascertained at baseline. RESULTS Over 3 years, fewer Māori (47%) than non-Māori (57%) fell; 19% of non-Māori and 20% of Māori scored 5+ (depressed) on the GDS. For non-Māori and Māori, people with depression were more likely to fall than Māori not diagnosed with depression (OR 2.72, CI 1.65-4.48 for non-Māori and OR 2.01, CI 1.25-3.25 for Māori). This remained significant, adjusted for age and sex. Depression was a significant predictor of hospitalisations from falls for Māori (OR 5.59, CI 2.4-12.72, adjusted for age and sex) and non-Māori (OR 4.21, 2.3-7.44, adjusted for sex). CONCLUSION Depression and falls are common and co-exist in octogenarians. GPs thinking about falls should also think about depression and vice versa.