Two RCTs and one meta-analysis (a systematic review of 42 papers) found that evidence is inconclusive regarding the association of specific circulating concentrations of 25-hydroxyvitamin D [25(OH)D] and bone health outcomes in post-menopausal women and older adult men. In those studies reporting a positive association in the meta-analysis, specific 25(OH)D concentrations ranging from 40nmol to 80nmol per L were shown to have declines in bone health outcomes (fractures, falls and bone loss). Further research is needed to determine the association of specific circulating concentrations of 25(OH)D with bone health outcomes.

• Grade I means there is Good/Strong evidence supporting the statement;
• Grade II is Fair;
• Grade III is Limited/Weak;
• Grade IV is Expert Opinion Only;
• Grade V is Not Assignable.
• High (A) means we are very confident that the true effect lies close to that of the estimate of the effect;
• Moderate (B) means we are moderately confident in the effect estimate;
• Low (C) means our confidence in the effect estimate is limited;
• Very Low (D) means we have very little confidence in the effect estimate.
• Ungraded means a grade is not assignable.

Thirteen studies regarding the primary risk factors for the development of osteoporosis in people with COPD were reviewed.  People with COPD are at increased risk for osteoporosis and/or vertebral fractures, and the prevalence ranges from 25% to 60%.  Four studies support a positive correlation between low body weight and/or BMI with decreased bone mineral density in subjects with COPD.  Additional risk factors reported include older age, smoking, and corticosteroid use.  Emerging research reports associations between hypercapnia, vitamin D status and bone mineral density; further research is needed in these areas.   

• Grade I means there is Good/Strong evidence supporting the statement;
• Grade II is Fair;
• Grade III is Limited/Weak;
• Grade IV is Expert Opinion Only;
• Grade V is Not Assignable.
• High (A) means we are very confident that the true effect lies close to that of the estimate of the effect;
• Moderate (B) means we are moderately confident in the effect estimate;
• Low (C) means our confidence in the effect estimate is limited;
• Very Low (D) means we have very little confidence in the effect estimate.
• Ungraded means a grade is not assignable.

Two RCTs and one meta-analysis (systematic review of 44 RCTs) found a direct effect of oral vitamin D₃ supplementation on circulating levels of 25(OH)D in post-menopausal women and older adult men. In studies reporting a treatment effect, specific doses ranging from five mcg to 50mcg (200 IU to 2,000 IU) of vitamin D₃ were utilized. Meta-regression results suggested that 100 IU (2.5mcg) of vitamin D₃ will increase the serum 25(OH)D concentrations by one nmol to two nmol per L suggesting doses of 400 IU to 800 IU (10mcg to 20mcg) daily may be inadequate to prevent vitamin D deficiency in at-risk individuals. It is difficult to determine adequate intake since there is a lack of agreement regarding optimal levels of serum 25(OH)D. Additional research is needed to determine the vitamin D dosage necessary to reach optimal serum 25(OH)D levels in post-menopausal women and older adult men.

• Grade I means there is Good/Strong evidence supporting the statement;
• Grade II is Fair;
• Grade III is Limited/Weak;
• Grade IV is Expert Opinion Only;
• Grade V is Not Assignable.
• High (A) means we are very confident that the true effect lies close to that of the estimate of the effect;
• Moderate (B) means we are moderately confident in the effect estimate;
• Low (C) means our confidence in the effect estimate is limited;
• Very Low (D) means we have very little confidence in the effect estimate.
• Ungraded means a grade is not assignable.

One meta-analysis (a systematic review of 19 studies), five RCTs and two cross-sectional studies found an association between supplemental vitamin D and bone mineral density (BMD) in post-menopausal women and older adult men. Vitamin D dosage ranged from 400 IU to 1,400 IU (10mcg to 35 mcg) per day, however it is difficult to determine the optimal dosage and the effect of vitamin D alone, since varying combinations of nutrients were used including calcium and vitamin K. One additional RCT with a supplement containing 200 IU (five mcg) of Vitamin D and other nutrients found an improvement in bone turnover markers, but no effect in bone mineral density. Further research is needed to determine the independent association between supplemental vitamin D and bone mineral density in post-menopausal women and older adult men.

• Grade I means there is Good/Strong evidence supporting the statement;
• Grade II is Fair;
• Grade III is Limited/Weak;
• Grade IV is Expert Opinion Only;
• Grade V is Not Assignable.
• High (A) means we are very confident that the true effect lies close to that of the estimate of the effect;
• Moderate (B) means we are moderately confident in the effect estimate;
• Low (C) means our confidence in the effect estimate is limited;
• Very Low (D) means we have very little confidence in the effect estimate.
• Ungraded means a grade is not assignable.

One meta-analysis/systematic review, combining the results of 13 RCTs suggest that supplementation with vitamin D₃ (400 IU to 800 IU) plus calcium (500mg to 1,200mg) may be beneficial in reducing the incidence of fractures in institutionalized older adults. The reduction of fractures might be accounted for by higher mean serum levels of 25(OH)D (at least 74nmol per L), due to good volunteer compliance. One RCT concluded that supplementation with 100,000 IU vitamin D₂ every four months, does not significantly reduce fractures in institutionalized older adults. Further research is needed to determine the role of vitamin D₃ and vitamin D₂ supplementation alone in reducing the incidence of fractures.

• Grade I means there is Good/Strong evidence supporting the statement;
• Grade II is Fair;
• Grade III is Limited/Weak;
• Grade IV is Expert Opinion Only;
• Grade V is Not Assignable.
• High (A) means we are very confident that the true effect lies close to that of the estimate of the effect;
• Moderate (B) means we are moderately confident in the effect estimate;
• Low (C) means our confidence in the effect estimate is limited;
• Very Low (D) means we have very little confidence in the effect estimate.
• Ungraded means a grade is not assignable.

One meta-analysis/systematic review, one RCT and one prospective cohort study found that evidence is inconsistent regarding the effect of supplemental vitamin D₂ or vitamin D₃ on the reduction of falls in older adult men and women. Further research is needed to determine the role of vitamin D₂ or vitamin D₃ alone in preventing falls in older adults.

• Grade I means there is Good/Strong evidence supporting the statement;
• Grade II is Fair;
• Grade III is Limited/Weak;
• Grade IV is Expert Opinion Only;
• Grade V is Not Assignable.
• High (A) means we are very confident that the true effect lies close to that of the estimate of the effect;
• Moderate (B) means we are moderately confident in the effect estimate;
• Low (C) means our confidence in the effect estimate is limited;
• Very Low (D) means we have very little confidence in the effect estimate.
• Ungraded means a grade is not assignable.

Clinical trials and cross-sectional studies have reported reduced bone mineral content and bone mineral density in untreated children, adolescents and adults with celiac disease; both of these parameters improve significantly with compliance to a gluten-free dietary pattern for at least 1 year.  Compliance with dietary treatment initiated during childhood or adolescence allows achievement of a normal bone mineralization.  However, studies in untreated adults have shown that a gluten-free dietary pattern improves but may not normalize bone mineral density; successful treatment depends on the age at diagnosis, as patients who do not receive treatment in childhood and adolescence may never reach peak bone mass.  Further studies are needed regarding the effects of calcium and vitamin D supplementation on bone mineral content and bone mineral density, as well as hormone replacement therapy for postmenopausal women. 

• Grade I means there is Good/Strong evidence supporting the statement;
• Grade II is Fair;
• Grade III is Limited/Weak;
• Grade IV is Expert Opinion Only;
• Grade V is Not Assignable.
• High (A) means we are very confident that the true effect lies close to that of the estimate of the effect;
• Moderate (B) means we are moderately confident in the effect estimate;
• Low (C) means our confidence in the effect estimate is limited;
• Very Low (D) means we have very little confidence in the effect estimate.
• Ungraded means a grade is not assignable.