| 181. |
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| 182. |
- Lorentzon, Mattias, 1970, et al.
(författare)
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Osteoporosis and fractures in women: the burden of disease
- 2022
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Ingår i: Climacteric. - : Informa UK Limited. - 1369-7137 .- 1473-0804. ; 25:1, s. 4-10
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Tidskriftsartikel (refereegranskat)abstract
- Osteoporosis is a disease characterized by impaired bone microarchitecture and reduced bone mineral density (BMD) resulting in bone fragility and increased risk of fracture. In western societies, one in three women and one in five men will sustain an osteoporotic fracture in their remaining lifetime from the age of 50 years. Fragility fractures, especially of the spine and hip, commonly give rise to increased morbidity and mortality. In the five largest European countries and Sweden, fragility fractures were the cause of 2.6 million disability-adjusted life years in 2016 and the fracture-related costs increased from euro29.6 billion in 2010 to euro37.5 billion in 2017. In the European Union and the USA, only a small proportion of women eligible for pharmacological treatment are being prescribed osteoporosis medication. Secondary fracture prevention, using Fracture Liaison Services, can be used to increase the rates of fracture risk assessment, BMD testing and use of osteoporosis medication in order to reduce fracture numbers. Additionally, established primary prevention strategies, based on case-finding methods utilizing fracture prediction tools, such as FRAX, to identify women without fracture but with elevated risk, are recommended in order to further reduce fracture numbers.
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| 183. |
- Lorentzon, Mattias, 1970, et al.
(författare)
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Osteoporosis epidemiology using international cohorts
- 2022
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Ingår i: Current Opinion in Rheumatology. - : Ovid Technologies (Wolters Kluwer Health). - 1040-8711 .- 1531-6963. ; 34:5, s. 280-288
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Tidskriftsartikel (refereegranskat)abstract
- Purpose of review To provide an update on the most important new cohort studies within osteoporosis and their bearing on clinical management and directions for future research. Recent findings We identified a collection of new observational cohort studies - including new reports from already established large cohorts - and intervention studies providing new insights into osteoporosis pathophysiology, risk finding, intervention, and treatment barriers. Recent cohort studies in osteoporosis highlight the importance of timely identification and treatment of people who are at high risk of suffering osteoporotic fractures. Physical performance is a strong indicator of fracture risk and one that is tightly linked to a number of chronic conditions, not least inflammatory conditions like rheumatoid arthritis. Advances in case finding may involve opportunistic screening for low bone mineral density and vertebral fractures of radiology images obtained for other purposes, polygenic risk scores, and routinely collected medication and comorbidity information.
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| 184. |
- Lorentzon, Mattias, 1970, et al.
(författare)
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Osteoporosis: the evolution of a diagnosis.
- 2015
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Ingår i: Journal of internal medicine. - : Wiley. - 1365-2796 .- 0954-6820. ; 277:6, s. 650-661
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Tidskriftsartikel (refereegranskat)abstract
- The global trend toward increased longevity has resulted in aging populations and a rise in diseases or conditions that primarily affect older persons. One such condition is osteoporosis (fragile or porous bones), which causes an increased fracture risk. Vertebral and hip fractures lead to increased morbidity and mortality and result in enormous healthcare costs. Here we review the evolution of the diagnosis of osteoporosis. In an attempt to separate patients with normal bones from those with osteoporosis and to define the osteoporosis diagnosis, multiple factors and characteristics have been considered. These include pathology and histology of the disease, the endocrine regulation of bone metabolism, bone mineral density (BMD), fracture type or trauma severity, risk models for fracture prediction, and thresholds for pharmacological intervention. The femoral neck BMD -2.5 SDs cut-off for the diagnosis of osteoporosis is arbitrarily chosen, and there is no evidence to support the notion that fracture location (except vertebral fractures) or severity is useful to discriminate osteoporotic from normal bones. Fracture risk models (including factors unrelated to bone) dissociate bone strength from the diagnosis, and treatment thresholds are often based on health-economic considerations rather than bone properties. Vertebral fractures are a primary feature of osteoporosis, characterized by decreased bone mass, strength, and quality and a high risk of another such fracture that can be considerably reduced by treatment. We believe that the 2001 definition of osteoporosis by the National Institutes of Health Consensus Development Panel on Osteoporosis is still valid and useful: 'Osteoporosis is defined as a skeletal disorder characterized by compromised bone strength predisposing a person to an increased risk of fracture'. This article is protected by copyright. All rights reserved.
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| 185. |
- Lorentzon, Mattias, 1970, et al.
(författare)
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Polymorphisms in the aromatase gene predict areal BMD as a result of affected cortical bone size: the GOOD study.
- 2006
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Ingår i: Journal of bone and mineral research : the official journal of the American Society for Bone and Mineral Research. - 0884-0431. ; 21:2, s. 332-9
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Tidskriftsartikel (refereegranskat)abstract
- The association between aromatase gene polymorphisms, bone parameters, and sex steroid levels was studied in 1068 men (18.9 +/- 0.6 years of age). Several aromatase gene polymorphisms were found to be associated with serum testosterone levels and cortical bone size but not with trabecular volumetric BMD. INTRODUCTION: Both testosterone and estrogens are important for the male skeleton. Aromatase, the product of the CYP19 gene, is the key enzyme in the conversion of testosterone to estradiol. A functional aromatase enzyme has been shown to be crucial for the normal development of the male skeleton. The role of genetic polymorphisms in the aromatase gene for trabecular volumetric BMD (vBMD) and cortical bone size has not previously been studied in men. MATERIALS AND METHODS: The Gothenburg Osteoporosis and Obesity Determinants (GOOD) study consists of 1068 men (18.9 +/- 0.6 years of age). The TTTA repeat polymorphism (TTTAn) and three single nucleotide polymorphisms (SNPs), including the Val80 SNP, in the CYP19 gene, were analyzed. Serum levels of testosterone and estradiol were measured. Areal BMD (aBMD) was measured by DXA, whereas cortical and trabecular vBMD and cortical bone size were measured by pQCT. RESULTS: The TTTAn and the Val80 genotypes were independent predictors of aBMD of the radius, lumbar spine, total body, and cortical bone size (cortical cross-sectional area and thickness) of both the radius and tibia. In contrast, trabecular vBMD was not associated with CYP19 polymorphisms. Homozygosity for the long allele (>9 repeats) of the TTTAn and for the G allele of the Val80 SNP was associated with the highest aBMD and testosterone levels as well as with the greatest cortical bone size. Regression analyses indicated that the association with aBMD was mediated through affected cortical bone size. CONCLUSIONS: We showed, in a large well-characterized cohort of men at the age of peak bone mass, that several common aromatase polymorphisms are associated with cortical bone size but not with trabecular vBMD. One may speculate that affected CYP19 activity, resulting in altered testosterone levels during pubertal development, might contribute to the association between CYP19 polymorphisms and cortical bone size.
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| 186. |
- Lorentzon, Mattias, 1970, et al.
(författare)
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Pubertal timing predicts leg length and childhood body mass index predicts sitting height in young adult men.
- 2011
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Ingår i: The Journal of pediatrics. - : Elsevier BV. - 1097-6833 .- 0022-3476. ; 158:3, s. 452-7
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Tidskriftsartikel (refereegranskat)abstract
- OBJECTIVE: To investigate the impact of pubertal timing and childhood body mass index (BMI), both within normal range, on adult anthropometrics. STUDY DESIGN: Detailed growth charts were retrieved for the men participating in the population-based Gothenburg Osteoporosis and Obesity Determinants study. Age at peak height velocity and childhood BMI were calculated (n = 527), and anthropometric measurements were performed. RESULTS: Analysis of variance analysis of tertiles according to age at peak height velocity demonstrated that the early peak height velocity tertile had a lower adult height (180.9 +/- 6.8 cm) compared with the middle tertile group (182.7 +/- 6.9 cm, P < .05), and this difference was attributable to shorter leg length. No difference was seen for sitting height. In contrast, analysis of tertiles according to childhood BMI demonstrated low sitting height in the low BMI tertile (93.7 +/- 3.3 cm for low, 94.6 +/- 3.3, for middle, and 94.8 +/- 3.3 cm for high childhood BMI tertiles, P < .05 and P < .01, respectively), but childhood BMI did not affect adult height and leg length. CONCLUSION: We demonstrate that subjects with early pubertal timing have reduced adult height and leg length, and subjects with low childhood BMI have reduced adult sitting height. Thus childhood body composition and pubertal timing have different impact on trunk growth and growth of long bones.
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| 187. |
- Lorentzon, Mattias, 1970, et al.
(författare)
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Reduced bone mineral density in SOCS-2-deficient mice.
- 2005
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Ingår i: Pediatric research. - 0031-3998. ; 57:2, s. 223-6
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Tidskriftsartikel (refereegranskat)abstract
- Suppressor of cytokine signaling-2 (SOCS-2) is a member of the suppressor of cytokine signaling family, implicated in the negative regulation of cytokine action through inhibition of the Janus kinase (JAK) signal transducers and activators of transcription (STAT) signal transduction pathway. We have previously reported that SOCS-2-/- mice display an increased longitudinal skeletal growth associated with a deregulated GH/IGF-I signaling. The aim of the present study was to determine the role of SOCS-2 in the regulation of bone mineral density (BMD). Dual x-ray absorptiometry (DXA) analyses demonstrated that the areal BMD of the tibia was reduced in both 4-wk-old (-8.6%) and 15-wk-old (-6.0%) SOCS 2-/- mice compared with wild-type (WT) mice. The trabecular volumetric BMD, as measured by peripheral quantitative computerized tomography (pQCT) in the metaphyseal region of the distal femur, was reduced in both 4-wk-old (-10%) and 15-wk-old (-32%) SOCS 2-/- mice compared with WT mice. pQCT analyses in the diaphyseal region of tibia also revealed that the cortical volumetric BMD was reduced in both 4-wk-old (-7%) and 15-wk-old (-3%) SOCS 2-/- mice. The cortical cross-sectional area was reduced in 4-wk-old but not in 15-wk-old SOCS 2-/- mice. In conclusion, SOCS-2 inactivation results in reduced trabecular and cortical volumetric BMD. These effects are not consistent with an augmented GH/IGF-I signaling and, therefore, the mechanism behind the reduced BMD remains to be elucidated.
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| 188. |
- Lorentzon, Mattias, 1970, et al.
(författare)
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Smoking is associated with lower bone mineral density and reduced cortical thickness in young men.
- 2007
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Ingår i: The Journal of clinical endocrinology and metabolism. - : The Endocrine Society. - 0021-972X .- 1945-7197. ; 92:2, s. 497-503
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Tidskriftsartikel (refereegranskat)abstract
- CONTEXT: Smoking has previously been associated with reduced areal bone mineral density (aBMD) in elderly subjects, but the association remains controversial in adolescents. OBJECTIVE: The aim of this study was to determine whether smoking was associated with aBMD or volumetric BMD (vBMD) and bone size in young men. DESIGN AND SETTING: aBMD was measured using dual x-ray absorptiometry. vBMD and bone size were measured using peripheral quantitative computerized tomography (pQCT). Smoking habits were assessed using questionnaires. Levels of sex steroids, PTH, and 25-OH-vitamin D were measured in serum. PARTICIPANTS: The population-based Gothenburg Osteoporosis and Obesity Determinants (GOOD) study includes 1068 young men, age 18.9 +/- 0.6 yr (mean +/- SD). MAIN OUTCOME MEASURE: The main outcome measure was smoking as predictor of bone parameters and serum sex hormone levels. RESULTS: Of the study subjects, 8.7% smoked daily. Bone parameters were compared between smokers and nonsmokers. Smokers had significantly lower aBMD (dual x-ray absorptiometry) of the total body (crude: -2.1%; adjusted for age, height, weight, calcium intake, and physical activity: -1.8%), lumbar spine (crude: -4.3%; adjusted: -3.3%), and trochanter (crude: -6.6%; adjusted: -5.0%) than nonsmokers. Using peripheral quantitative computerized tomography, we found that smokers had lower cortical thickness of both the radius (crude: -2.8%; adjusted: -2.9%) and tibia (crude: -4.5%; adjusted: -4.0%) than the nonsmokers, whereas no difference was seen for cortical vBMD. Smokers had higher serum levels of total and free testosterone and lower 25-OH-vitamin D than nonsmokers. Adjustment for testosterone and/or 25-OH-vitamin D levels did not alter the associations between smoking and bone parameters. CONCLUSIONS: We demonstrate that smoking was associated with lower aBMD and reduced cortical thickness in young men.
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| 189. |
- Lorentzon, Mattias, 1970, et al.
(författare)
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The COMT val158met polymorphism is associated with peak BMD in men.
- 2004
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Ingår i: Journal of bone and mineral research : the official journal of the American Society for Bone and Mineral Research. - 0884-0431. ; 19:12, s. 2005-11
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Tidskriftsartikel (refereegranskat)abstract
- The associations between the functional val158met polymorphism of the estrogen-degrading COMT enzyme and skeletal properties in young men were investigated. BMD was associated with COMT genotype. INTRODUCTION: Peak BMD is an important predictor of future risk of osteoporosis, and it is to a large extent determined by genetic factors. Estrogens are involved in the accretion of bone mass during puberty. Catechol-O-methyltransferase (COMT) is involved in the degradation of estrogens. There is a functional polymorphism in the COMT gene (val158met), resulting in a 60-75% difference in enzyme activity between the val (high activity [H]) and met (low activity [L]) variants. The aim of this cross-sectional study was to investigate the associations between this polymorphism and peak BMD in young men. MATERIALS AND METHODS: A total of 458 healthy men (mean age, 19 +/- 0.6 years) were genotyped and classified as COMT(LL), COMT(HL), or COMT(HH). Areal BMD (aBMD) was measured by DXA. Cortical and trabecular volumetric BMD (vBMD) were measured by pQCT. The associations between COMT genotype and skeletal phenotypes were determined. RESULTS AND CONCLUSIONS: Regression models using physical activity, height, weight, age, and COMT genotype as covariates showed that COMT genotype was an independent predictor of aBMD in the total body and in all femur locations investigated, but not in the spine. The values for COMT(HL) and COMT(HH) were very similar, and therefore, they were pooled into one group. aBMD at Ward's triangle, trochanter, and total femur were 4.9%, 4.5%, and 3.7% lower, respectively, in the COMT(LL) than in the COMT(HL/HH) group (p < 0.01). pQCT analyses showed that COMT genotype was an independent predictor of trabecular vBMD of the tibia, radius, and fibula. Trabecular vBMD of the radius and fibula in COMT(LL) was 5.3% and 7.4% lower, respectively, than that of the combined COMT(HL/HH) group. COMT genotype was associated with cortical vBMD but not with cortical cross-sectional area in the tibia. These findings show that the COMT polymorphism is associated with BMD in young adult men.
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