This article summarizes the new 2011 report on dietary requirements for calcium and vitamin D from the Institute of Medicine (IOM). An IOM Committee charged with determining the population needs for these nutrients in North America conducted a comprehensive review of the evidence for both skeletal and extraskeletal outcomes. The Committee concluded that available scientific evidence supports a key role of calcium and vitamin D in skeletal health, consistent with a cause-and-effect relationship and providing a sound basis for determination of intake requirements. For extraskeletal outcomes, including cancer, cardiovascular disease, diabetes, and autoimmune disorders, the evidence was inconsistent, inconclusive as to causality, and insufficient to inform nutritional requirements. Randomized clinical trial evidence for extraskeletal outcomes was limited and generally uninformative. Based on bone health, Recommended Dietary Allowances (RDAs; covering requirements of ≥97.5% of the population) for calcium range...

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The 2011 Report on Dietary Reference Intakes for Calcium and Vitamin D from the Institute of Medicine: What Clinicians Need to Know

The charge to the committee (Institute of Medicine Committee to Review Dietary Reference Intakes for Vitamin D and Calcium) was to assess current relevant data and update, as appropriate, the DRIs (Dietary Reference Intakes) for vitamin D and calcium. The review was to include consideration of chronic disease indicators (e.g., reduction in risk of cancer) and other (non-chronic disease) indicators and health outcomes. The definitions of these terms are discussed below. Consistent with the framework for DRI development, the indicators to assess adequacy and excess intake were to be selected based on the strength and quality of the evidence and their demonstrated public health significance, taking into consideration sources of uncertainty in the evidence. Further, the committee deliberations were to incorporate, as appropriate, systematic evidence-based reviews of the literature.Specifically, in carrying out its work, the committee was to: Review evidence on indicators to assess adequacy and indicators to assess excess intake relevant to the general North American population, including groups whose needs for or sensitivity to the nutrient may be affected by particular conditions that are widespread in the population such as obesity or age-related chronic diseases. Special groups under medical care whose needs or sensitivities are affected by rare genetic disorders or diseases and their treatments were to be excluded; Consider systematic evidence-based reviews, including those made available by the sponsors as well as others, and carefully document the approach used by the committee to carry out any of its own literature reviews; Regarding selection of indicators upon which to base DRI values for adequate intake, give priority to selecting indicators relevant to the various age, gender, and life stage groups that will allow for the determination of an Estimated Average Requirement (EAR); Regarding selection of indicators upon which to base DRI values for upper levels of intake, give priority to examining whether a critical adverse effect can be selected that will allow for the determination of a so-called benchmark intake; Update DRI values, as appropriate, using a risk assessment approach that includes (1) identification of potential indicators to assess adequacy and excess intake, (2) selection of the indicators of adequacy and excess intake, (3) intake-response assessment, (4) dietary intake assessment, and (5) risk characterization. Identify research gaps to address the uncertainties identified in the process of deriving the reference values and evaluating their public health implications.

Dietary Reference Intakes for Calcium and Vitamin D

QUITE apart from the academic consideration that vital and medical statistics now form an obligatory part of the education of students seeking the University of London's diploma in public health, the demand for information about the methods of vital and medical statistics is increasing. The most casual reader of the newspapers is now aware that population problems are of serious practical importance and that the publications of the General Register Office cannot be ignored. It is scarcely an exaggeration to say that the recently issued preliminary report on the census of 1931 is one of the most sensational documents which has appeared for years, and that he who reads it intelligently will understand what is meant by saying that civilisation is in the melting pot. An Introduction to Medical Statistics. By Hilda M. Woods William T. Russell. Pp. x + 125. (London: P. S. King and Son, Ltd., 1931.) 7s. 6d.

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An Introduction to Medical Statistics

Context Understanding the incidence and subsequent mortality following hip fracture is essential to measuring population health and the value of improvements in health care. Objective To examine trends in hip fracture incidence and resulting mortality over 20 years in the US Medicare population. Design, Setting, and Patients Observational study using data from a 20% sample of Medicare claims from 1985-2005. In patients 65 years or older, we identified 786 717 hip fractures for analysis. Medication data were obtained from 109 805 respondents to the Medicare Current Beneficiary Survey between 1992 and 2005. Main Outcome Measures Age- and sex-specific incidence of hip fracture and age- and risk-adjusted mortality rates. Results Between 1986 and 2005, the annual mean number of hip fractures was 957.3 per 100 000 (95% confidence interval [CI], 921.7-992.9) for women and 414.4 per 100 000 (95% CI, 401.6-427.3) for men. The age-adjusted incidence of hip fracture increased from 1986 to 1995 and then steadily declined from 1995 to 2005. In women, incidence increased 9.0%, from 964.2 per 100 000 (95% CI, 958.3-970.1) in 1986 to 1050.9 (95% CI, 1045.2-1056.7) in 1995, with a subsequent decline of 24.5% to 793.5 (95% CI, 788.7-798.3) in 2005. In men, the increase in incidence from 1986 to 1995 was 16.4%, from 392.4 (95% CI, 387.8-397.0) to 456.6 (95% CI, 452.0-461.3), and the subsequent decrease to 2005 was 19.2%, to 369.0 (95% CI, 365.1-372.8). Age- and risk-adjusted mortality in women declined by 11.9%, 14.9%, and 8.8% for 30-, 180-, and 360-day mortality, respectively. For men, age- and risk-adjusted mortality decreased by 21.8%, 25.4%, and 20.0% for 30-, 180-, and 360-day mortality, respectively. Over time, patients with hip fracture have had an increase in all comorbidities recorded except paralysis. The incidence decrease is coincident with increased use of bisphosphonates. Conclusion In the United States, hip fracture rates and subsequent mortality among persons 65 years and older are declining, and comorbidities among patients with hip fractures have increased.

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Incidence and mortality of hip fractures in the United States.

Objective To test the efficacy of supplemental vitamin D and active forms of vitamin D with or without calcium in preventing falls among older individuals. Data sources We searched Medline, the Cochrane central register of controlled trials, BIOSIS, and Embase up to August 2008 for relevant articles. Further studies were identified by consulting clinical experts, bibliographies, and abstracts. We contacted authors for additional data when necessary. Review methods Only double blind randomised controlled trials of older individuals (mean age 65 years or older) receiving a defined oral dose of supplemental vitamin D (vitamin D 3 (cholecalciferol) or vitamin D 2 (ergocalciferol)) or an active form of vitamin D (1α-hydroxyvitamin D 3 (1α-hydroxycalciferol) or 1,25-dihydroxyvitamin D 3 (1,25-dihydroxycholecalciferol)) and with sufficiently specified fall assessment were considered for inclusion. Results Eight randomised controlled trials (n=2426) of supplemental vitamin D met our inclusion criteria. Heterogeneity among trials was observed for dose of vitamin D (700-1000 IU/day v 200-600 IU/day; P=0.02) and achieved 25-hydroxyvitamin D 3 concentration (25(OH)D concentration: v ≥60 nmol/l; P=0.005). High dose supplemental vitamin D reduced fall risk by 19% (pooled relative risk (RR) 0.81, 95% CI 0.71 to 0.92; n=1921 from seven trials), whereas achieved serum 25(OH)D concentrations of 60 nmol/l or more resulted in a 23% fall reduction (pooled RR 0.77, 95% CI 0.65 to 0.90). Falls were not notably reduced by low dose supplemental vitamin D (pooled RR 1.10, 95% CI 0.89 to 1.35; n=505 from two trials) or by achieved serum 25-hydroxyvitamin D concentrations of less than 60 nmol/l (pooled RR 1.35, 95% CI 0.98 to 1.84). Two randomised controlled trials (n=624) of active forms of vitamin D met our inclusion criteria. Active forms of vitamin D reduced fall risk by 22% (pooled RR 0.78, 95% CI 0.64 to 0.94). Conclusions Supplemental vitamin D in a dose of 700-1000 IU a day reduced the risk of falling among older individuals by 19% and to a similar degree as active forms of vitamin D. Doses of supplemental vitamin D of less than 700 IU or serum 25-hydroxyvitamin D concentrations of less than 60 nmol/l may not reduce the risk of falling among older individuals.

https://www.bmj.com/content/bmj/339/bmj.b3692.full.pdf

Fall prevention with supplemental and active forms of vitamin D: a meta-analysis of randomised controlled trials

Objectives To review and synthesize the literature in the following areas: the association of specific circulating 25(OH)D concentrations with bone health outcomes in children, women of reproductive age, postmenopausal women and elderly men; the effect of dietary intakes (foods fortified with vitamin D and/or vitamin D supplementation) and sun exposure on serum 25(OH)D; the effect of vitamin D on bone mineral density (BMD) and fracture or fall risk; and the identification of potential harms of vitamin D above current reference intakes. Data sources MEDLINE(R) (1966-June Week 3 2006); Embase (2002-2006 Week 25); CINAHL (1982-June Week 4, 2006); AMED (1985 to June 2006); Biological Abstracts (1990-February 2005); and the Cochrane Central Register of Controlled Trials (2nd Quarter 2006). Review methods Two independent reviewers completed a multi-level process of screening the literature to identify eligible studies (title and abstract, followed by full text review, and categorization of study design per key question). To minimize bias, study design was limited to randomized controlled trials (RCTs) wherever possible. Study criteria for question one were broadened to include observational studies due to a paucity of available RCTs, and question four was restricted to systematic reviews to limit scope. Data were abstracted in duplicate and study quality assessed. Differences in opinion were resolved through consensus or adjudication. If clinically relevant and statistically feasible, meta-analyses of RCTs on vitamin D supplementation and bone health outcomes were conducted, with exploration of heterogeneity. When meta-analysis was not feasible, a qualitative systematic review of eligible studies was conducted. Results 167 studies met our eligibility criteria (112 RCTs, 19 prospective cohorts, 30 case-controls and six before-after studies). The largest body of evidence on vitamin D status and bone health was in older adults with a lack of studies in premenopausal women and infants, children and adolescents. The quality of RCTs was highest in the vitamin D efficacy trials for prevention of falls and/or fractures in older adults. There was fair evidence of an association between low circulating 25(OH)D concentrations and established rickets. However, the specific 25(OH)D concentrations associated with rickets is uncertain, given the lack of studies in populations with dietary calcium intakes similar to North American diets and the different methods used to determine 25(OH)D concentrations. There was inconsistent evidence of an association of circulating 25(OH)D with bone mineral content in infants, and fair evidence that serum 25(OH)D is inversely associated with serum PTH. In adolescents, there was fair evidence for an association between 25(OH)D levels and changes in BMD. There were very few studies in pregnant and lactating women, and insufficient evidence for an association between serum 25(OH)D and changes in BMD during lactation, and fair evidence of an inverse correlation with PTH. In older adults, there was fair evidence that serum 25(OH)D is inversely associated with falls, fair evidence for a positive association with BMD, and inconsistent evidence for an association with fractures. The imprecision of 25(OH)D assays may have contributed to the variable thresholds of 25(OH)D below which the risk of fractures, falls or bone loss was increased. There was good evidence that intakes from vitamin D-fortified foods (11 RCTs) consistently increased serum 25(OH)D in both young and older adults. Eight randomized trials of ultraviolet (UV)-B radiation (artificial and solar exposure) were small and heterogeneous with respect to determination of the exact UV-B dose and 25(OH)D assay but there was a positive effect on serum 25(OH)D concentrations. It was not possible to determine how 25(OH)D levels varied by ethnicity, sunscreen use or latitude. Seventy-four trials examined the effect of vitamin D(3) or D(2) on 25(OH)D concentrations. Most trials used vitamin D(3), and the majority enrolled older adults. In three trials, there was a greater response of serum 25(OH)D concentrations to vitamin D(3) compared to vitamin D(2), which may have been due to more rapid clearance of vitamin D(2) in addition to other mechanisms. Meta-analysis of 16 trials of vitamin D(3) was consistent with a dose-response effect on serum 25(OH)D when comparing daily doses of /= 400 IU. An exploratory analysis of the heterogeneity demonstrated a significant positive association comparable to an increase of 1 - 2 nmol/L in serum 25(OH)D for every 100 additional units of vitamin D although heterogeneity remained after adjusting for dose. Vitamin D(3) in combination with calcium results in small increases in BMD compared to placebo in older adults although quantitative synthesis was limited due to variable treatment durations and BMD sites. The evidence for fracture reduction with vitamin D supplementation was inconsistent across 15 trials. The combined results of trials using vitamin D(3) (700 - 800 IU daily) with calcium (500 - 1,200 mg) was consistent with a benefit on fractures although in a subgroup analysis by setting, benefit was primarily in elderly institutionalized women (fair evidence from two trials). There was inconsistent evidence across 14 RCTs of a benefit on fall risk. However, a subgroup analysis showed a benefit of vitamin D in postmenopausal women, and in trials that used vitamin D(3) plus calcium. In addition, there was a reduction in fall risk with vitamin D when six trials that adequately ascertained falls were combined. Limitations of the fall and fracture trials included poor compliance with vitamin D supplementation, incomplete assessment of vitamin D status and large losses to follow-up. We did not find any systematic reviews that addressed the question on the level of sunlight exposure that is sufficient to maintain serum 25(OH)D concentrations but minimizes risk of melanoma and non-melanoma skin cancer. There is little evidence from existing trials that vitamin D above current reference intakes is harmful. In most trials, reports of hypercalcemia and hypercalciuria were not associated with clinically relevant events. The Women's Health Initiative study did report a small increase in kidney stones in postmenopausal women aged 50 to 79 years whose daily vitamin D(3) intake was 400 IU (the reference intake for 50 to 70 years, and below the reference intake for > 70 years) combined with 1000 mg calcium. The increase in renal stones corresponded to 5.7 events per 10,000 person-years of exposure. The women in this trial had higher calcium intakes than is seen in most post-menopausal women. Conclusions The results highlight the need for additional high quality studies in infants, children, premenopausal women, and diverse racial or ethnic groups. There was fair evidence from studies of an association between circulating 25(OH)D concentrations with some bone health outcomes (established rickets, PTH, falls, BMD). However, the evidence for an association was inconsistent for other outcomes (e.g., BMC in infants and fractures in adults). It was difficult to define specific thresholds of circulating 25(OH)D for optimal bone health due to the imprecision of different 25(OH)D assays. Standard reference preparations are needed so that serum 25(OH)D can be accurately and reliably measured, and validated. In most trials, the effects of vitamin D and calcium could not be separated. Vitamin D(3) (>700 IU/day) with calcium supplementation compared to placebo has a small beneficial effect on BMD, and reduces the risk of fractures and falls although benefit may be confined to specific subgroups. Vitamin D intake above current dietary reference intakes was not reported to be associated with an increased risk of adverse events. However, most trials of higher doses of vitamin D were not adequately designed to assess long-term harms.

http://www.reboundhealth.com/cms/images/pdf/MedicalAbstract/effectiveness%20and%20safety%20of%20vitamin%20d%20in%20relation%20to%20bone%20health%20id%2016060.pdf

Effectiveness and safety of vitamin D in relation to bone health.

Context Hip fractures are a public health concern because they are associated with significant morbidity, excess mortality, and the majority of the costs directly attributable to osteoporosis. Objective To examine trends in hip fracture rates in Canada. Design, Setting, and Patients Ecologic trend study using nationwide hospitalization data for 1985 to 2005 from a database at the Canadian Institute for Health Information. Data for all patients with a hospitalization for which the primary reason was a hip fracture (570 872 hospitalizations) were analyzed. Main Outcome Measures Age-specific and age-standardized hip fracture rates. Results There was a decrease in age-specific hip fracture rates (all P for trend Conclusions Age-standardized rates of hip fracture have steadily declined in Canada since 1985 and more rapidly during the later study period. The factors primarily responsible for the earlier reduction in hip fractures are unknown.

https://jamanetwork.com/journals/jama/articlepdf/184467/joc90086_883_889.pdf

Trends in hip fracture rates in Canada.

"Arthritis" describes more than 100 conditions that affect the joints, the tissues that surround joints and other connective tissue. These conditions range from relatively mild forms of tendonitis and bursitis to systemic illnesses, such as rheumatoid arthritis. Life with arthritis in Canada: a personal and public health challenge presents the latest knowledge about arthritis in the Canadian population and its wide-ranging impact. It provides an overview of the impact of arthritis, and is designed to increase public awareness of the importance of prevention and timely management. Although progress has been made on interventions, arthritis remains common, disabling and costly. Increasing participation in physical activity and maintaining a healthy body weight may help to mitigate the effects of arthritis.

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Life with arthritis in Canada: a personal and public health challenge.

Efficacy of food fortification on serum 25-hydroxyvitamin D concentrations: systematic review

Over the next few decades, hip fractures will be a major public health concern as the number of elderly, a population at high risk for osteoporosis, increases substantially. The rising incidence of hip fracture is a concern for both afflicted individuals and the health care system because these fractures are associated with significant morbidity, mortality, and costs. This study investigated trends of hip fractures in Canada from 1985 to 2005 through analysis of national databases on hospitalization and morbidity. The primary study outcome measures were age-specific and age-standardized hip fracture rates. The Cochran-Armitage test for linear trend was used to estimate yearly changes in age-specific hip fracture subgroups. Joinpoint regression analysis identified points at which a statistically significant change over time occurred in the linear slope of the trends in hip fracture rates. Over the 21 years of observation, 570,872 cases of hospitalization for hip fractures were identified. A progressive decrease in age-specific hip fracture rates occurred over time among both males (25.0%) and females (31.8%) (P < 0.001 for both): Age-adjusted hip fracture rates among females decreased from 118.6 per 100,000 person-years (95% confidence interval [CI], 115.9-121.4) in 1985 to 80.9 (95% CI, 79.2-82.6) in 2005. Similarly, the age-adjusted hip fracture rates for males decreased from 68.2 per 100,000 person-years (95% CI, 65.6-70.8) to 51.1 (95% CI, 49.4-52.7). Among males and females, joinpoint regression analysis identified a change in the linear slope around 1996. During the early part of the study (1985-1996), the average percentage decrease per year in hip fracture rates was 1.2% (95% CI, 1.0%-1.3%) whereas during the later part of the study (1996-2005), the decrease was 2.4% (95% CI, 2.1%-2.6%) per year from 1996 to 2005 (P < 0.001 for difference in slopes in both time periods). Large changes occurred among both females and males with greater slope reductions after 1996 (P < 0.001 for difference in slopes for both). These findings demonstrate significant progressive decreases in age-standardized rates of hip fracture between 1985 and 2005 and show a more rapid decline in rates in the second half of the study period. The factors contributing to the earlier reduction in hip fracture at a time when there was no widespread diagnostic testing or modern drug therapy are unknown.

Siobhan O'Donnell

Papers

Effectiveness and safety of vitamin D in relation to bone health.

Trends in hip fracture rates in Canada.

Life with arthritis in Canada: a personal and public health challenge.

Efficacy of food fortification on serum 25-hydroxyvitamin D concentrations: systematic review

Trends in Hip Fracture Rates in Canada