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Biomedical subjects

Heike A Bischoff-Ferrari

Publications and source records attributed to Heike A Bischoff-Ferrari.

12 recordsLinked to original sources
PubMed2007

The 25-hydroxyvitamin D threshold for better health.

Available data supporting a target serum level of at least 75 nmol/l 25-hydroxyvitamin D (25-OHD) include studies on bone mineral density (bmd), fracture prevention, lower extremity function, and cancer prevention. Given the high cost and disability from falls, fractures, and cancer treatment a shared threshold for 25-OHD has significant public health implications, especially so, if a large part of the population is below this threshold. This article summarizes available evidence supporting the 75 nmol/l threshold, reviews adherence to Vitamin D treatment in fracture trials in regard to achieved anti-fracture efficacy, and finally discusses current recommendations for Vitamin D intake.

Bone Density↗
PubMed2006

Effect of cholecalciferol plus calcium on falling in ambulatory older men and women: a 3-year randomized controlled trial.

BACKGROUND: A recent meta-analysis found that cholecalciferol (vitamin D) should reduce falls by more than 20%. However, little is known about whether supplemental cholecalciferol plus calcium citrate malate will lower the long-term risk of falling in men, active older individuals, and older individuals with higher 25-hydroxyvitamin D levels. METHODS: We studied the effect of 3-year supplementation with cholecalciferol-calcium on the risk of falling at least once in 199 men and 246 women 65 years or older and living at home. Individuals received 700 IU of cholecalciferol plus 500 mg of calcium citrate malate per day or placebo in a randomized double-blind manner. Subjects were classified as less physically active if physical activity was below the median level. Low 25-hydroxyvitamin D levels were classified as those below 32 ng/mL (<80 nmol/L). RESULTS: In 3 years, 55% of women and 45% of men reported at least 1 fall. Mean +/- SD baseline 25-hydroxyvitamin D levels were 26.6 +/- 12.7 ng/mL (66.4 +/- 31.7 nmol/L) in women and 33.2 +/- 14.2 ng/mL (82.9 +/- 34.9) in men. Cholecalciferol-calcium significantly reduced the odds of falling in women (odds ratio [OR], 0.54; 95% confidence interval [CI], 0.30-0.97), but not in men (OR, 0.93; 95% CI, 0.50-1.72). Fall reduction was most pronounced in less active women (OR, 0.35; 95% CI, 0.15-0.81). Baseline 25-hydroxyvitamin D level did not modulate the treatment effect. CONCLUSIONS: Long-term dietary cholecalciferol-calcium supplementation reduces the odds of falling in ambulatory older women by 46%, and especially in less active women by 65%. Supplementation had a neutral effect in men independent of their physical activity level.

Accidental Falls↗
PubMed2006

Estimation of optimal serum concentrations of 25-hydroxyvitamin D for multiple health outcomes.

Recent evidence suggests that vitamin D intakes above current recommendations may be associated with better health outcomes. However, optimal serum concentrations of 25-hydroxyvitamin D [25(OH)D] have not been defined. This review summarizes evidence from studies that evaluated thresholds for serum 25(OH)D concentrations in relation to bone mineral density (BMD), lower-extremity function, dental health, and risk of falls, fractures, and colorectal cancer. For all endpoints, the most advantageous serum concentrations of 25(OH)D begin at 75 nmol/L (30 ng/mL), and the best are between 90 and 100 nmol/L (36-40 ng/mL). In most persons, these concentrations could not be reached with the currently recommended intakes of 200 and 600 IU vitamin D/d for younger and older adults, respectively. A comparison of vitamin D intakes with achieved serum concentrations of 25(OH)D for the purpose of estimating optimal intakes led us to suggest that, for bone health in younger adults and all studied outcomes in older adults, an increase in the currently recommended intake of vitamin D is warranted. An intake for all adults of > or =1000 IU (25 microg) [DOSAGE ERROR CORRECTED] vitamin D (cholecalciferol)/d is needed to bring vitamin D concentrations in no less than 50% of the population up to 75 nmol/L. The implications of higher doses for the entire adult population should be addressed in future studies.

Age Factors↗
PubMed2005

Positive association between serum 25-hydroxyvitamin D level and bone density in osteoarthritis.

OBJECTIVE: To describe the association between serum 25-hydroxyvitamin D (25[OH]D) level and bone mineral density (BMD) in persons with primary knee osteoarthritis (OA). METHODS: We conducted a population-based survey of the Framingham Study. A total of 228 subjects with primary radiographic knee OA were identified. For vitamin D status, 25(OH)D levels < or =15 ng/ml were classified as vitamin D deficient, 25(OH)D levels 16-32 ng/ml were classified as hypovitaminosis D, and 25(OH)D levels >32 ng/ml were classified as vitamin D replete. We compared average BMD between categories of 25(OH)D levels in subjects with OA using a linear regression model while adjusting for sex, age, body mass index (BMI), knee pain, physical activity, cohort, and disease severity. RESULTS: Mean age was 74.4 years and 36% were men. Of 228 individuals, 15% were vitamin D deficient, 51% had hypovitaminosis D, and 34% were vitamin D replete. Compared with subjects with vitamin D deficiency, those with hypovitaminosis D had a 7.3% higher BMD (adjusted percent difference; P = 0.02) and vitamin D replete subjects had an 8.5% higher BMD (adjusted percent difference; P = 0.02; test for trend across categories: P = 0.04). CONCLUSION: We observed a significant positive association between serum 25(OH)D and BMD in individuals with primary knee OA, independent of sex, age, BMI, knee pain, physical activity, and disease severity. Given the high prevalence of low 25(OH)D status in persons with knee OA and the positive association between 25(OH)D and BMD, vitamin D supplementation may enhance BMD in individuals with OA.

Adult↗
PubMed2005

Vitamin D intake and risk of incident hypertension: results from three large prospective cohort studies.

Emerging evidence suggests an inverse relation between vitamin D and blood pressure. We examined the independent association between intake of vitamin D and the risk of incident hypertension among participants of 3 large and independent prospective cohorts: Nurses Health Study I (NHS I; n=77,436), NHS II (n=93,803), and Health Professionals' Follow-up Study (HPFS; n=38,074). Relative risks and 95% confidence intervals for incident hypertension were computed according to quintiles of vitamin D intake using Cox proportional hazards regression and adjusted for relevant covariates. Each cohort was followed for > or =8 years. Vitamin D intake was not associated with the risk of developing hypertension. The multivariable relative risk estimates for the highest compared with lowest quintile of intake were 0.98 (0.93 to 1.04) in NHS I, 1.13 (0.99 to 1.29) in NHS II, and 1.03 (0.93 to 1.15) in HPFS. When we compared participants who consumed > or =1600 to <400 IU per day and those who consumed > or =1000 to <200 IU per day, no association was found. We conclude that higher intake of vitamin D is not associated with a lower risk of incident hypertension.

Adult↗
PubMed2005

Fracture prevention with vitamin D supplementation: a meta-analysis of randomized controlled trials.

CONTEXT: The role and dose of oral vitamin D supplementation in nonvertebral fracture prevention have not been well established. OBJECTIVE: To estimate the effectiveness of vitamin D supplementation in preventing hip and nonvertebral fractures in older persons. DATA SOURCES: A systematic review of English and non-English articles using MEDLINE and the Cochrane Controlled Trials Register (1960-2005), and EMBASE (1991-2005). Additional studies were identified by contacting clinical experts and searching bibliographies and abstracts presented at the American Society for Bone and Mineral Research (1995-2004). Search terms included randomized controlled trial (RCT), controlled clinical trial, random allocation, double-blind method, cholecalciferol, ergocalciferol, 25-hydroxyvitamin D, fractures, humans, elderly, falls, and bone density. STUDY SELECTION: Only double-blind RCTs of oral vitamin D supplementation (cholecalciferol, ergocalciferol) with or without calcium supplementation vs calcium supplementation or placebo in older persons (> or =60 years) that examined hip or nonvertebral fractures were included. DATA EXTRACTION: Independent extraction of articles by 2 authors using predefined data fields, including study quality indicators. DATA SYNTHESIS: All pooled analyses were based on random-effects models. Five RCTs for hip fracture (n = 9294) and 7 RCTs for nonvertebral fracture risk (n = 9820) met our inclusion criteria. All trials used cholecalciferol. Heterogeneity among studies for both hip and nonvertebral fracture prevention was observed, which disappeared after pooling RCTs with low-dose (400 IU/d) and higher-dose vitamin D (700-800 IU/d), separately. A vitamin D dose of 700 to 800 IU/d reduced the relative risk (RR) of hip fracture by 26% (3 RCTs with 5572 persons; pooled RR, 0.74; 95% confidence interval [CI], 0.61-0.88) and any nonvertebral fracture by 23% (5 RCTs with 6098 persons; pooled RR, 0.77; 95% CI, 0.68-0.87) vs calcium or placebo. No significant benefit was observed for RCTs with 400 IU/d vitamin D (2 RCTs with 3722 persons; pooled RR for hip fracture, 1.15; 95% CI, 0.88-1.50; and pooled RR for any nonvertebral fracture, 1.03; 95% CI, 0.86-1.24). CONCLUSIONS: Oral vitamin D supplementation between 700 to 800 IU/d appears to reduce the risk of hip and any nonvertebral fractures in ambulatory or institutionalized elderly persons. An oral vitamin D dose of 400 IU/d is not sufficient for fracture prevention.

Aged↗
PubMed2005

Association between serum concentrations of 25-hydroxyvitamin D and gingival inflammation.

BACKGROUND: Vitamin D has been shown to have immunomodulatory effects in in vitro and in animal studies. However, data from clinical studies of inflammatory diseases are scarce. OBJECTIVE: The purpose of this study was to evaluate the association between serum concentrations of 25-hydroxyvitamin D [25(OH)D] and gingival inflammation. DESIGN: We analyzed data from 77,503 gingival units (teeth) in 6700 never smokers aged 13 to >90 y from the third National Health and Nutrition Examination Survey. Multiple logistic regression models adjusted for subject- and site-specific covariates included age, sex, race-ethnicity, income, body mass index, diabetes, use of oral contraceptives and hormone replacement therapy among women, intake of vitamin C, missing teeth, full crown coverage, presence of calculus, frequency of dental visits, and dental examiner and survey phase. Generalized estimating equations were used to account for correlated observations within subjects. RESULTS: Compared with sites in subjects in the lowest 25(OH)D quintile, sites in subjects in the highest 25(OH)D quintile were 20% (95% CI: 8%, 31%) less likely to bleed on gingival probing (P for trend < 0.001). The association appeared to be linear over the entire 25(OH)D range, was consistent across racial or ethnic groups, and was similar among men and women as well as among users and nonusers of vitamin and mineral supplements. CONCLUSIONS: Vitamin D may reduce susceptibility to gingival inflammation through its antiinflammatory effects. Gingivitis may be a useful clinical model to evaluate the antiinflammatory effects of vitamin D.

Adolescent↗
PubMed2004

Effect of Vitamin D on falls: a meta-analysis.

CONTEXT: Falls among elderly individuals occur frequently, increase with age, and lead to substantial morbidity and mortality. The role of vitamin D in preventing falls among elderly people has not been well established. OBJECTIVE: To assess the effectiveness of vitamin D in preventing an older person from falling. DATA SOURCES: MEDLINE and the Cochrane Controlled Trials Register from January 1960 to February 2004, EMBASE from January 1991 to February 2004, clinical experts, bibliographies, and abstracts. Search terms included trial terms: randomized-controlled trial or controlled-clinical trial or random-allocation or double-blind method, or single-blind method or uncontrolled-trials with vitamin D terms: cholecalciferol or hydroxycholecalciferols or calcifediol or dihydroxycholecalciferols or calcitriol or vitamin D/aa[analogs & derivates] or ergocalciferol or vitamin D/bl[blood]; and with accidental falls or falls, and humans. STUDY SELECTION: We included only double-blind randomized, controlled trials (RCTs) of vitamin D in elderly populations (mean age, 60 years) that examined falls resulting from low trauma for which the method of fall ascertainment and definition of falls were defined explicitly. Studies including patients in unstable health states were excluded. Five of 38 identified studies were included in the primary analysis and 5 other studies were included in a sensitivity analysis. DATA EXTRACTION: Independent extraction by 3 authors using predefined data fields including study quality indicators. DATA SYNTHESIS: Based on 5 RCTs involving 1237 participants, vitamin D reduced the corrected odds ratio (OR) of falling by 22% (corrected OR, 0.78; 95% confidence interval [CI], 0.64-0.92) compared with patients receiving calcium or placebo. From the pooled risk difference, the number needed to treat (NNT) was 15 (95% CI, 8-53), or equivalently 15 patients would need to be treated with vitamin D to prevent 1 person from falling. The inclusion of 5 additional studies, involving 10 001 participants, in a sensitivity analysis resulted in a smaller but still significant effect size (corrected RR, 0.87; 95% CI, 0.80-0.96). Subgroup analyses suggested that the effect size was independent of calcium supplementation, type of vitamin D, duration of therapy, and sex, but reduced sample sizes made the results statistically nonsignificant for calcium supplementation, cholecalciferol, and among men. CONCLUSIONS: Vitamin D supplementation appears to reduce the risk of falls among ambulatory or institutionalized older individuals with stable health by more than 20%. Further studies examining the effect of alternative types of vitamin D and their doses, the role of calcium supplementation, and effects in men should be considered.

Accidental Falls↗
PubMed2004

Association between serum concentrations of 25-hydroxyvitamin D3 and periodontal disease in the US population.

BACKGROUND: Periodontal disease (PD) is a common chronic inflammatory disease and an important risk factor for tooth loss. Vitamin D might affect periodontal disease risk via an effect on bone mineral density (BMD) or via immunomodulatory effects. OBJECTIVE: The objective was to evaluate whether serum 25-hydroxyvitamin D(3) [25(OH)D(3)] concentrations are associated with PD in the third National Health and Nutrition Examination Survey. DESIGN: We analyzed data on periodontal attachment loss (AL) and serum 25(OH)D(3) concentrations from 11 202 subjects aged > or =20 y. Mean AL was modeled in a multiple linear regression with quintile of serum 25(OH)D(3) concentration as an independent variable. The model was stratified by age and sex and was adjusted for age within age groups, race or ethnicity, smoking, diabetes, poverty income ratio, body mass index, estrogen use, and gingival bleeding. RESULTS: 25(OH)D(3) concentrations were significantly and inversely associated with AL in men and women aged > or =50 y. Compared with men in the highest 25(OH)D(3) quintile, those in the lowest quintile had a mean AL that was 0.39 mm (95% CI: 0.17, 0.60 mm) higher; in women, the difference in AL between the lowest and highest quintiles was 0.26 mm (0.09, 0.43 mm). In men and women younger than 50 y, there was no significant association between 25(OH)D(3) and AL. The BMD of the total femoral region was not associated with AL and did not mediate the association between 25(OH)D(3) and AL. CONCLUSIONS: Low serum 25(OH)D(3) concentrations may be associated with PD independently of BMD. Given the high prevalence of PD and vitamin D deficiency, these findings may have important public health implications.

Adult↗
PubMed2004

Higher 25-hydroxyvitamin D concentrations are associated with better lower-extremity function in both active and inactive persons aged > or =60 y.

BACKGROUND: Vitamin D may improve muscle strength through a highly specific nuclear receptor in muscle tissue. OBJECTIVES: We investigated whether there is an association between 25-hydroxyvitamin D [25(OH)D] concentrations and lower-extremity function in ambulatory older persons, whether that association differs by activity level, and, if so, whether there is an identifiable threshold in the association. DESIGN: The study was a population-based survey of the ambulatory US population aged 60 to > or =90 y (n = 4100). Lower-extremity function according to serum 25(OH)D concentrations was assessed by linear regression analyses and regression plots after control for activity level (inactive or active) and several other potential confounders. Separate analyses were performed for the timed 8-foot (ie, 2.4 m) walk test and a repeated sit-to-stand test. RESULTS: The 8-foot walk test compared subjects in the lowest and highest quintiles of 25(OH)D; the latter group had an average decrease of 0.27 s [95% CI: -0.44, -0.09 s (or 5.6%); P for trend < 0.001]. The sit-to-stand test compared subjects in the lowest and highest quintiles of 25(OH)D; the latter group had an average decrease of 0.67 s [95% CI: -1.11, -0.23 s (or 3.9%); P for trend = 0.017]. In the 25(OH)D reference range of 22.5-94 nmol/L, most of the improvement occurred in subjects with 25(OH)D concentrations between 22.5 and approximately 40 nmol/L, and further improvement was seen in the range of 40-94 nmol/L. Stratification by activity level showed no significant effect modification. CONCLUSION: In both active and inactive ambulatory persons aged > or =60 y, 25(OH)D concentrations between 40 and 94 nmol/L are associated with better musculoskeletal function in the lower extremities than are concentrations < 40 nmol/L.

Aged↗