Eva Ribom

Type I Collagen α1 Sp1 Polymorphism and the Risk of Cruciate Ligament Ruptures or Shoulder Dislocations

Background Cruciate ligament ruptures and shoulder dislocations are often caused by trauma, but predisposing intrinsic factors might also influence the risk. These injuries are more common in those with a previously injured sibling, an observation that might indicate a genetic predisposition. It is well known that polymorphisms in the collagen I gene are associated not only with osteoporosis and osteoporotic fracture risk, but also with osteoarthritis. Hypothesis Because collagen I is abundant in ligaments and tendons, the authors hypothesized that collagen I α1 Sp1 polymorphism also was related to the occurrence of cruciate ligament ruptures and shoulder dislocations. Study Design Case-control study; Level of evidence, 3. Methods A total of 358 patients and 325 randomly selected population-based female controls were included in the study. Of the cases, 233 had a cruciate ligament rupture and 126 had had a shoulder dislocation. Age-adjusted odds ratios (ORs) with 95% confidence intervals (CIs) estimated by unconditional logistic regression were used as measures of association. Results Compared with the homozygous SS category, the heterozygous participants displayed a similar risk (OR, 1.06; 95% CI, 0.76–1.49), whereas the ss genotype was underrepresented in the injured population compared with the controls (OR, 0.15; 95% CI, 0.03–0.68). This latter estimate was similar for both cruciate ligament ruptures and shoulder dislocations, and was furthermore not modified by general joint laxity. Conclusion The authors found a substantially decreased risk of these injuries associated with collagen type I α1 Sp1 polymorphism. The study might encourage other investigators to consider further research in the area of genes and soft tissue injuries.

Six months of hormone replacement therapy does not influence muscle strength in postmenopausal women

OBJECTIVES Postmenopausal hormone replacement therapy (HRT) has positive effects on fracture incidence before any effects on bone mineral density can be demonstrated. This has been attributed to increased muscle strength by HRT. This study was designed to evaluate the effect of 6 months of HRT on muscle strength in postmenopausal women. METHODS Forty postmenopausal women, aged 60-78 were included in the study. They were randomly divided in two groups with 20 women in each group. One group received Menorest 50 microg/24 h (estradiol 4.3 mg) and Gestapuran 2.5 mg (medroxyprogesteron) daily and the other group received placebo treatment. The study was conducted as a double blinded, prospective and placebo controlled trial. Hand grip strength, isokinetic knee flexion and extention, and physical activity were measured before treatment, after 3 and 6 months. Physical activity was estimated using a classification system of physical activity. A JAMAR hydraulic hand dynamometer and a Cybex II dynamometer were used to evaluate muscle strength. RESULTS Hand grip strength in the right hand, increased significantly in both groups (HRT P<0.001 and placebo P<0.01) and in the left hand in the HRT group (P<0.01). However, there were no differences in muscle strength between the two groups. There was no significant change in isokinetic knee flexion or extension after 6 months in either of the groups. The estimated physical activity increased slightly in the placebo group, but there was no significant difference compared to the treatment group. CONCLUSIONS Our data suggest that 6 months of HRT does not influence muscle strength in postmenopausal women.

Muscle strength correlates with total body bone mineral density in young women but not in men

Background: Osteoporosis is a growing health problem. One of the proposed reasons for this is a more sedentary lifestyle. The aim of this study was to investigate the associations between muscle strength and total body bone mineral density (TBMD) in young adults at expected peak bone mass.

A Poly Adenosine Repeat in the Human Vitamin D Receptor Gene is Associated with Bone Mineral Density in Young Swedish Women

AbstractPeak bone mass (PBM) and subsequent bone loss are important risk factors for development of osteoporosis later in life, and twin studies have reported strong genetic influence on PBM. The genetic factor influencing PBM is polygenetic, and many genes most likely exert relatively small effects on bone mass. The poly adenosine (A) microsatellite in the 3′ untranslated region (UTR) of the VDR gene has been associated with both prostate and breast cancer risk but little is known about the effect of bone mineral density (BMD). In this report the poly A microsatellite and the linked BsmI SNP have been investigated in a population-based cohort of 343 Swedish women, aged 20–39. BMD was measured by dual x-ray absorptiometry at the spine, proximal femur, total body and heel and by quantitative ultrasound at the heel. Correlations were found between VDR genotypes and BMD at lumbar spine L2-L4, (ss versus LL , P = 0.03 and BB versus bb, P = 0.02, respectively), with a similar pattern concerning total hip (ss versus LL, P = 0.12 and BB versus bb, P = 0.16 respectively). After corrections for age, height, fat and lean mass, the VDR BsmI genotype was still associated to BMD at the lumbar spine (BB versus bb, P = 0.03). The polymorphisms were in linkage disequilibrium (Chi-square = 566, P < 0.0001). In conclusion, genetic variation in the VDR is associated with BMD in premenopausal women, and further studies are needed to evaluate a possible functional role of the VDR 3′UTR poly A repeat, a region that has shown to be of important for mRNA stability.

Inferior physical performance test results of 10,998 men in the MrOS Study is associated with high fracture risk

BACKGROUND most fractures are preceded by falls. OBJECTIVE the aim of this study was to determine whether tests of physical performance are associated with fractures. SUBJECTS a total of 10,998 men aged 65 years or above were recruited. METHODS questionnaires evaluated falls sustained 12 months before administration of the grip strength test, the timed stand test, the six-metre walk test and the twenty-centimetre narrow walk test. Means with 95% confidence interval (95% CI) are reported. P < 0.05 is a statistically significant difference. RESULTS fallers with a fracture performed worse than non-fallers on all tests (all P < 0.001). Fallers with a fracture performed worse than fallers with no fractures both on the right-hand-grip strength test and on the six-metre walk test (P < 0.001). A score below -2 standard deviations in the right-hand-grip strength test was associated with an odds ratio of 3.9 (95% CI: 2.1-7.4) for having had a fall with a fracture compared with having had no fall and with an odds ratio of 2.6 (95% CI: 1.3-5.2) for having had a fall with a fracture compared with having had a fall with no fracture. CONCLUSION the right-hand-grip strength test and the six-metre walk test performed by old men help discriminate fallers with a fracture from both fallers with no fracture and non-fallers.

Estimation of physical performance and measurements of habitual physical activity may capture men with high risk to fall—Data from the Mr Os Sweden cohort

To evaluate if clinically usable estimates of physical performance and level of habitual physical activity are associated with fall risk in elderly men. A population-based sample of 3014 randomly selected men aged 69-80 years was recruited to medical centers in Gothenburg, Malmoe, or Uppsala. The level of physical activity and self-reported falls during the preceding 12 months was evaluated using a questionnaire. The physical performance ability was estimated by measurements of handgrip strength, a timed stands test, a 6-m walking test and a 20-cm narrow walk test. Falls were reported in 16.5% of the men. Fallers performed 6.2+/-19.0% (mean+/-standard deviations; S.D.) less in right handgrip measures, 8.8+/-40.6% slower in the timed stands test, 6.8+/-30.8% slower in the 6-m walking test, and 5.3+/-28.8% slower in the 20-cm narrow walk test (all p<0.001, respectively). The odds ratio for falls among men who performed <-3 S.D. or failed compared to the mean (+1 S.D. to -1 S.D.) in the timed stands test was 3.41 (95% CI 2.31-5.02; p<0.001) and 2.46 (95% CI 1.80-3.34; p<0.001) in 20-cm narrow walk test. There were more fallers that never were physical active (73.0% vs. 65.4%, p<0.001) and who were sitting more (6.4+/-2.5 h/day vs. 6.0+/-2.3 h/day, p<0.05) than among the non-fallers. Fallers scored less than non-fallers in all the estimates of physical performance and they were more sedentary in their life style. The report suggests that clinical usable tests of physical performance and evaluation of habitual physical activity in the clinical situation possibly can be used to predict risk of falls in elderly men.

Population-based reference values of handgrip strength and functional tests of muscle strength and balance in men aged 70-80 years

With aging, the incidence of falls and fractures increases. There has during the last decades been secular changes in demographics so that the proportion of elderly increases in society. Hence, there is an increasing need for clinicians to be able to make a solid appraisal of the elderly patients functional capacity, as to identify individuals with an increased risk to fall. If high risk individuals could be targeted fall preventive strategies might be implemented in specific risk cohorts. This would require reference values for muscle strength tests and functional tests, in order to defined high risk individuals performing inferior. From the MrOS Sweden cohort, 999 subjects aged 70-80 years were evaluated. Muscle strength and functional performance was tested by timed-stands test, 6-m and 20-cm narrow walk tests and Jamar handgrip strength test. Normative data is presented. With increasing age, there was a 10-18% successively decline in performance throughout the entire age span. This study provides reference values for handgrip strength and functional muscle tests in 70-80 years old men. The decline in the test values with increasing age, infer the use of age-specific normative data when using these tests both in clinical and research settings.

Use of a Swedish T-Score Reference Population for Women Causes a Two-Fold Increase in the Amount of Postmenopausal Swedish Patients that Fulfill the WHO Criteria for Osteoporosis

The WHO criteria for osteoporosis are based on bone mineral density (BMD) values in comparison to a reference population of healthy young adults. The aim of this study was to create BMD references for ethnic Swedish women, and to investigate whether the use of these T-score measurements influence the amount of Swedish postmenopausal patients that are diagnosed as having osteoporosis. A bone density reference was created by measuring a population-based sample of 335 randomly selected Swedish women aged 20-39yr. BMD was measured by dual-energy X-ray absorptiometry (DXA) at the lumbar spine, proximal femur, and total body. These locally derived T-score values were subsequently used to diagnose a sample of 300 consecutive postmenopausal Swedish patients referred to the Uppsala Osteoporosis Unit. There was a slight age-dependent decrease in femoral neck BMD, whereas no age effect was seen at other sites such as total hip, lumbar spine, or total body. This suggests that the cohort represents the steady state BMD at the ages of expected peak bone mass in Swedish women. The correlation between BMD measures at different sites differed from r=0.55 (lumbar spine BMD vs femoral neck BMD [FNBMD]) to r=0.92 (total hip BMD vs FNBMD). Central DXA-generated T-scores were calculated from this cohort, and these were significantly higher (0.3-0.5 SD) as compared with manufacturers and NHANESIII reference populations. This indicates that young Swedish women have a higher peak bone mass than the subjects included in the reference populations currently used for clinical measurements. The T-score in total hip derived from the investigated cohort was subsequently used to diagnose 300 clinical patients (mean age 63yr) referred for a DXA scan by their physicians. The use of this locally established and ethnic representative, T-score reference increased the prevalence of osteoporosis in femoral neck and total hip with 53-106%. A Swedish female BMD reference representing peak bone mass has been established and the normative data are presented. Notably, this cohort has considerably higher BMD as compared to the NHANESIII and manufacturers reference populations. The use of the present T-score reference therefore causes approximately a 2-fold increase in the amount of Swedish postmenopausal women that fulfill the WHO criteria for osteoporosis. This demonstrates the problems with using T-score as diagnostic threshold for osteoporosis and is an argument for future strategies to obtain standardized densitometric cut-offs, for example, mg/cm(2).

International and ethnic variability of falls in older men.

Aims: Fallers and especially recurrent fallers are at high risk for injuries. The aim of this study was to evaluate fall epidemiology in older men with special attention to the influence of age, ethnicity and country of residence. Methods: 10,998 men aged 65 years or above recruited in Hong Kong, the United States (US) and Sweden were evaluated in a cross-sectional retrospective study design. Self-reported falls and fractures for the preceding 12 months were registered through questionnaires. Group comparisons were done by chi-square test or logistic regression. Results: The proportion of fallers among the total population was 16.5% in ages 65–69, 24.8% in ages 80–84 and 43.2% in ages above 90 (P <0.001). The corresponding proportions of recurrent fallers in the same age groups were 6.3%, 10.1% and 18.2%, respectively (P <0.001), and fallers with fractures 1.0%, 2.3% and 9.1%, respectively (P <0.001). The proportion of fallers was highest in the US, intermediate in Sweden and lowest in Hong Kong (in most age groups P <0.05). The proportion of fallers among white men in the US was higher than in white men in Sweden (all comparable age groups P <0.01) but there were no differences in the proportion of fallers in US men with different ethnicity. Conclusions: The proportion of fallers in older men is different in different countries, and data in this study corroborate with the view that society of residence influences fall prevalence more than ethnicity.

There is in elderly men a group difference between fallers and non-fallers in physical performance tests

There is in elderly men a group difference between fallers and non-fallers in physical performance tests