1. |
- Michaëlsson, Karl, 1959-, et al.
(författare)
-
Dietary calcium and vitamin D intake in relation to osteoporotic fracture risk
- 2003
-
Ingår i: Bone. - 8756-3282 .- 1873-2763. ; 32:6, s. 694-703
-
Tidskriftsartikel (refereegranskat)abstract
- The etiologic role of dietary calcium and vitamin D intake in primary prevention of osteoporotic fractures is uncertain, despite considerable research efforts. With the aim to examine these associations with an improved precision, we used data from a large population-based prospective cohort study in central Sweden. We estimated nutrient intake from a self-administered food-frequency questionnaire filled in by 60,689 women, aged 40-74 years at baseline during 1987-1990. During follow-up, we observed 3986 women with a fracture at any site and 1535 with a hip fracture. Rate ratio of fractures (RR) and 95% CI were estimated using Cox proportional hazards models. We found no dose-response association between dietary calcium intake and fracture risk. The age-adjusted RR of hip fracture was 1.01 (95% CI 0.96-1.06) per 300 mg calcium/day and the corresponding risk of any osteoporotic fracture was 0.99 (95% CI 0.96-1.03). Furthermore, women with an estimated calcium intake below 400 mg/day and those with a calcium intake higher than 1200 mg/day both had a similar age-adjusted hip fracture risk as those with intermediate calcium intakes: RR 1.07 (95% CI 0.92-1.24) and RR 1.00 (95% CI 0.79-1.27), respectively. Vitamin D intake was not associated with fracture risk. Furthermore, women in the highest quintiles compared to the lowest quintiles of both calcium and vitamin D intake had an age-adjusted RR of 1.02 for all fractures (95% CI 0.88-1.17). Dietary calcium or vitamin D intakes estimated at middle and older age do not seem to be of major importance for the primary prevention of osteoporotic fractures in women.
|
|
2. |
- Michaëlsson, Karl, 1959-, et al.
(författare)
-
Use of low potency estrogens does not reduce the risk of hip fracture
- 2002
-
Ingår i: Bone. - 8756-3282 .- 1873-2763. ; 30:4, s. 613-618
-
Tidskriftsartikel (refereegranskat)abstract
- High endogenous sexual hormone levels and use of medium potency estrogens are associated with a reduced risk of hip fracture in postmenopausal women. However, it is not clear if low potency estrogens confer the same benefits as the more widely used forms of menopausal hormone replacement. We examined the association between postmenopausal use of low potency estrogens, mainly estriol, and hip fracture risk in a population-based, case-control study. Using data from mailed questionnaires and telephone interviews, we analyzed the association between low potency estrogen use and hip fracture risk among 1327 cases, 50-81 years of age, and 3262 randomly selected age-matched controls. Ever use of low potency estrogens was reported by 19% of the cases and 23% of controls. Compared to with never users of any hormone replacement therapy, ever users of low potency estrogens had a multivariate odds ratio (OR) for hip fracture of 0.96 (95% confidence interval [CI] 0.67-1.39). Current use was also not associated with a reduction in risk: OR 0.94 (95% CI 0.58-1.53), and longer duration of use was also not associated with a risk reduction. Even current use of the highest dose of oral estriol (2 mg/day) conferred no risk reduction (OR 1.01, 95% CI 0.61-1.67) compared with never use of hormone replacement therapy. After exclusion of ever users of medium potency estrogens from the analyses, we found a risk reduction of fracture among current vaginal low potency estrogen users (multivariate OR 0.67, 95% CI 0.49-0.92). In contrast to medium potency estrogens, low potency estrogens did not confer a substantial overall reduction in hip fracture risk.
|
|
3. |
- Engstrom, Annette, et al.
(författare)
-
Associations between dietary cadmium exposure and bone mineral density and risk of osteoporosis and fractures among women
- 2012
-
Ingår i: Bone. - : Elsevier BV. - 8756-3282 .- 1873-2763. ; 50:6, s. 1372-1378
-
Tidskriftsartikel (refereegranskat)abstract
- Osteoporosis and its main health outcome, fragility fractures, are large and escalating public health problems. Cadmium, a widespread food contaminant, is a proposed risk factor; still the association between estimated dietary cadmium exposure and bone mineral density (BMD) has never been assessed. Within a sub-cohort of the Swedish Mammography Cohort, we assessed dietary cadmium exposure based on a food frequency questionnaire (1997) and urinary cadmium (2004-2008) in relation to total-body BMD and risk of osteoporosis and fractures (1997-2009) among 2676 women (aged 56-69 years). In multivariable-adjusted linear regression, dietary cadmium was inversely associated with BMD at the total body and lumbar spine. After further adjustment for dietary factors important for bone health and cadmium bioavailability-calcium, magnesium, iron and fiber, the associations became more pronounced. A 32% increased risk of osteoporosis (95% Cl: 2-71%) and 31% increased risk for any first incident fracture (95% Cl; 2-69%) were observed comparing high dietary cadmium exposure (>= 13 mu g/day, median) with lower exposures (<13 mu g/day). By combining high dietary with high urinary cadmium (>= 0.50 mu g/g creatinine), odds ratios among never-smokers were 2.65 (95% Cl: 1.43-4.91) for osteoporosis and 3.05 (95% Cl; 1.66-5.59) for fractures. In conclusion, even low-level cadmium exposure from food is associated with low BMD and an increased risk of osteoporosis and fractures. The partial masking of the associations by essential nutrients indicates important interplay between dietary factors and contaminants present in food. In separate analyses, dietary and urinary cadmium underestimated the association with bone effects.
|
|
4. |
|
|
5. |
- Hantikainen, Essi, et al.
(författare)
-
Prospective study of dietary Non Enzymatic Antioxidant Capacity on the risk of hip fracture in the elderly
- 2016
-
Ingår i: Bone. - : Elsevier BV. - 8756-3282 .- 1873-2763. ; 90, s. 31-36
-
Tidskriftsartikel (refereegranskat)abstract
- Background: Dietary antioxidants may play an important role in the prevention of bone loss and associated fractures by reducing levels of oxidative stress. We prospectively investigated the association between dietary Non Enzymatic Antioxidant Capacity (NEAC) and the risk of hip fracture and whether this effect was modified by smoking. Method: In the Swedish National March Cohort 13,409 men and women over the age of 55 who had not experienced cancer, cardiovascular disease or hip fracture, were followed through record-linkages from 1997 through 2010. NEAC was assessed by a validated food frequency questionnaire collected at baseline. We categorized the distribution of NEAC into sex-specific quartiles and used multivariable adjusted Cox proportional hazards regression models to estimate hazard ratios (HRs) with 95% confidence intervals (95% CI). Results: During a mean follow-up time of 12.4 years, we identified 491 incident cases of first hip fracture. Subjects in the highest quartile of dietary NEAC had a 39% lower risk of incident hip fracture compared to those in the lowest quartile (HR: 0.61; 95% CI: 0.44-0.85). The association was non-linear (p for non-linearity: 0.004) with a potential threshold between the first and the second quartile and no further risk reduction at higher levels of dietary NEAC. Due to a low smoking prevalence in our study population, we had limited power to detect effect modification between dietary NEAC and smoking on a multiplicative or additive scale. Conclusion: Higher dietary NEAC intake is associated with lower risk of hip fracture in the elderly.
|
|
6. |
- Karampampa, Korinna, et al.
(författare)
-
Declining incidence trends for hip fractures have not been accompanied by improvements in lifetime risk or post-fracture survival - A nationwide study of the Swedish population 60 years and older
- 2015
-
Ingår i: Bone. - : Elsevier BV. - 8756-3282 .- 1873-2763. ; 78, s. 55-61
-
Tidskriftsartikel (refereegranskat)abstract
- Background: Hip fracture is a common cause of disability and mortality among the elderly. Declining incidence trends have been observed in Sweden. Still, this condition remains a significant public health problem since Sweden has one of the highest incidences worldwide. Yet, no Swedish lifetime risk or survival trends have been presented. By examining how hip fracture incidence, post-fracture survival, as well as lifetime risk have developed between 1995 and 2010 in Sweden, this study aims to establish how the burden hip fractures pose on the elderly changed over time, in order to inform initiatives for improvements of their health. Material and Methods: The entire Swedish population 60 years-old and above was followed between 1987 and 2010 in the National Patient Register and the Cause of Death Register. Annual age-specific hip fracture cumulative incidence was estimated using hospital admissions for hip fractures. Three-month and one-year survival after the first hip fracture were also estimated. Period life table was used to assess lifetime risk of hip fractures occuring from age 60 and above, and the expected mean age of the first hip fracture. Results: The age-specific hip fracture incidence decreased between 1995 and 2010 in all ages up to 94 years, on average by 1% per year. The lifetime risk remained almost stable, between 9% and 11% for men, and between 18% and 20% for women. The expected mean age of a first hip fracture increased by 2.5 years for men and by 2.2 years for women. No improvements over time were observed for the 3-month survival for men, while for women a 1% decrease per year was observed. The 1-year survival slightly increased over time for men (0.4% per year) while no improvement was observed for women. Conclusions: The age-specific hip fracture incidence has decreased overtime. Yet the lifetime risk of a hip fracture has not decreased because life expectancy in the population has increased in parallel. Overall, survival after hip fracture has not improved.
|
|
7. |
- Larsson, Susanna C, et al.
(författare)
-
Mendelian randomization in the bone field
- 2019
-
Ingår i: Bone. - : Elsevier BV. - 8756-3282 .- 1873-2763. ; 126, s. 51-58
-
Tidskriftsartikel (refereegranskat)abstract
- Identification of causative risk factors amenable for modification is essential for the prevention and treatment of osteoporosis. Observational studies have identified associations between several potentially modifiable risk factors and osteoporosis. However, observational studies are susceptible to confounding, reverse causation bias, and measurement error, all of which limit their ability to provide causal estimates of the effect of exposures on outcomes, thereby reducing their ability to inform prevention and treatment strategies against bone loss and fractures. In addition, not all risk factors are suitable for an analysis in a randomized clinical trial. Mendelian randomization is a genetic epidemiological method that exploits genetic variants as unbiased proxies for modifiable exposures (e.g., biomarkers, adiposity measures, dietary factors, and behaviors) to determine the causal relationships between exposures and health outcomes. This technique has been used to provide evidence of causal associations of serum estradiol concentrations, smoking, body mass index, and type 2 diabetes with bone mineral density and the lack of associations of serum thyroid stimulating hormone, urate, C-reactive protein, and 25‑hydroxyvitamin D concentrations with bone mineral density in generally healthy populations. This review will briefly explain the concept of Mendelian randomization, the advantages and potential limitations of this study design, and give examples of how Mendelian randomization has been used to investigate questions relevant to osteoporosis.
|
|
8. |
|
|
9. |
- Michaëlsson, Karl, et al.
(författare)
-
The positive effect of dietary vitamin D intake on bone mineral density in men is modulated by the polyadenosine repeat polymorphism of the vitamin D receptor
- 2006
-
Ingår i: Bone. - : Elsevier BV. - 8756-3282 .- 1873-2763. ; 39:6, s. 1343-1351
-
Tidskriftsartikel (refereegranskat)abstract
- INTRODUCTION: Few studies have considered the dietary influence of vitamin D intake on bone mineral density (BMD). Numerous studies have examined the association between VDR polymorphism and BMD, but no previous study has examined the joint influence of dietary vitamin D intake and VDR polymorphism on BMD. METHODS: We therefore conducted a study in 230 men aged 41-76 years of age. BMD was measured with DXA. A second bone scan was performed on average 2.7 years after the first investigation. Dietary habits were assessed by 14 dietary 24-h recall interviews. The polyadenosine (A) VDR genotypes were determined. RESULTS: Dietary vitamin D intake was associated with BMD at all sites, also after multivariate adjustment. Those in the highest quintile of intake had 9% higher femoral neck BMD (p = 0.004), 6% higher BMD at the lumbar spine (p = 0.06) and 5% higher total body BMD (p = 0.003) compared to men in the lowest quintile of dietary vitamin D intake. However, the positive association between vitamin D intake and BMD was especially apparent among those with the L/L polyadenosine (A) VDR genotype explaining between 10 and 15% of the variability in BMD depending on site (p < 0.004). There was furthermore a trend, in the lumbar spine, of less reduction in BMD with increasing vitamin D intake (p = 0.07) but not at the other sites. Calcium intake conferred no association with BMD. CONCLUSIONS: Our results indicate that the extent of positive association between dietary vitamin D intake and BMD in men is dependent on VDR polymorphism, a novel conceivable important gene-environmental interaction.
|
|
10. |
- Schilcher, Jörg, et al.
(författare)
-
Atypical femoral fractures are a separate entity, characterized by highly specific radiographic features. A comparison of 59 cases and 218 controls
- 2013
-
Ingår i: Bone. - : Elsevier. - 8756-3282 .- 1873-2763. ; 52:1, s. 389-392
-
Tidskriftsartikel (refereegranskat)abstract
- Background: Estimations of the risk of bisphosphonate associated atypical femoral fractures vary between different population-based studies, from considerable to neglectable. A possible explanation for these discrepancies could be different definitions of atypical fractures. We aimed to identify specific radiographic fracture characteristics associated with bisphosphonate use. less thanbrgreater than less thanbrgreater thanMethods: In a previous nationwide study, 59 atypical and 218 ordinary fractures were diagnosed. The atypical fractures were defined by their stress-type fracture pattern. All fractures were now re-assessed by a physician in training, without information about bisphosphonate use. The fracture angle (0-180 degrees) was measured. Presence of local lateral cortical thickening (a callus reaction), more than 2 fragments, or a medial spike was noted. The reader then made a judgment whether the fracture appeared as an atypical fracture based on the ASBMR criteria. less thanbrgreater than less thanbrgreater thanResults: Frequency distribution analysis of the fracture angle showed a distinct subgroup, comprising 25% of all 277 fractures, with a mean of 89 and SD of 10 degrees. Forty-two of 57 patients in this subgroup used bisphosphonates, whereas only 27 of 213 others did (specificity 0.93; 95% CI 0.88-0.96). Presence of a callus reaction had also a high specificity for bisphosphonate use (0.96; 95% CI 0.92-0.98). The ASBMR criteria had a lower specificity, increasing the number of atypical fractures without bisphosphonate use from 13 to 31. This led to a decrease in age-adjusted relative risk associated with bisphosphonate use from 47 (95% CI 26-87) to 19 (95% CI 12-29). less thanbrgreater than less thanbrgreater thanInterpretation: Stress fractures of the femoral shaft are a specific entity, which is easily diagnosed on radiographs and strongly related to bisphosphonate use. Differences in diagnostic criteria may partially explain the large differences in relative risk between different population-based studies.
|
|