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Biomedical subjects

O Johnell

Publications and source records attributed to O Johnell.

At least 127 records · Page 7Linked to original sources
PubMed1998

Circumstances around the fall in a multinational hip fracture risk study: a diverse pattern for prevention. MEDOS Study Group). Mediterranean Osteoporosis Study.

Hip fracture is a major public health problem, but with a potential for prevention. Data from a European multicentre study on hip fracture epidemiology with a case control design, the MEDOS study, were used to describe and analyse circumstances around falls associated with hip fracture. The study includes 2185 fracture cases age > 50 years from 14 centres in southern Europe: Portugal, Spain, France, Italy, Greece and Turkey. Information was collected by a standardized and validated questionnaire translated into six languages and administered by trained interviewers. Circumstances around the fall were categorized according to: (1) place, age group and time of day; (2) functional disability; (3) drug consumption including alcohol; and (4) environmental factors. Possibilities for prevention were also analysed. High risk falls were identified using seven reasonably well-established risk factors, and similarly eight risk factors were used to identify high risk fallers. Selected trains of events were also studied. A pattern of great diversity was found both among the fallers and the environment in which they fell and fractured the hip. Those with more than one factor involved constituted only 14.7% of female and 19.7% of male fractures. A majority of cases were not physically disabled before the fall. A majority (66.5%) fell and fractured their hip indoors and only 4.3% outside in darkness. Cardiovascular and cerebrovascular comborbidity were observed with 4.9 and 7.8%, of falls respectively. Falls in a stairway comprised 11% of falls. The correlation between the number of the risk factors of the faller and in the environment was 0.07 and there was no difference between males and females. The pattern of causality behind falls that cause hip fracture and therefore of prevention comprises many sometimes small groups and intricate time sequence. The results suggest that global preventive strategies could presently not be implemented. Instead, the pattern of prevention should include different target groups and be country and site specific. For the high risk group of institutionalized patients prevention can be implemented without delay.

Accidental Falls↗
PubMed1998

Osteopromotive membranes enhance onlay integration and maintenance in the adult rat skull.

This study aimed to evaluate the effect of an osteopromotive membrane technique on onlay bone graft survival. Unicortical bone grafts were positioned bilaterally below the temporal muscle in 21 adult Lewis rats. In 14 rats, the bone graft on the right side was covered by an expanded polytetrafluoroethylene GORE-TEX membrane, whereas that on the left side was left uncovered. Seven rats were killed after 12 (group 1) and 20 (group 2) weeks, respectively. The remaining animals (n = 7, group 3) received membranes bilaterally, of which the right-sided membrane was removed after 12 weeks, and these animals were killed after 20 weeks. The specimens were assessed by routine histology and immunohistochemical labelling for various matrix proteins. After 12 weeks (group 1), size differences between the sides were not significant, although all control onlay bone grafts showed microscopic signs of pronounced resorption. At 20 weeks (group 2), graft integration was more complete on the membrane side. For group 3, the height was significantly more preserved on the side where the membrane was not removed. Immunolabelling demonstrated a more intense bone remodelling at the membrane sites. Membrane treatment resulted in improved graft integration and significantly greater size persistence, but complete height was not maintained.

Animals↗
PubMed1998

Assessment of sex hormones and bone mineral density in relation to occurrence of fracture in men: a prospective population-based study.

Patients with fragility fractures have low bone mineral density (BMD)--this statement is supported mainly by data on women. In this study, including only men, the objectives were to determine whether a decline in BMD alone or in combination with data on male sex hormones and skinfold thickness could be of value in predicting forthcoming fractures. We also wanted to find out whether high consumers of alcohol can be identified by measuring BMDs and male sex hormones. A prospective, population-based study was performed in the city of Malmö, Sweden. 242 men were randomly selected; all were of Scandinavian ethnic background, and were aged 50, 60, 70, and 80 years. Forearm BMD, testosterone, sex-hormone-binding globulin (SHBG), and skinfold thickness were analyzed. In addition, alcohol consumption and carbohydrate-deficient transferrin (CDT)--a marker of alcohol abuse--were analyzed. The study group was followed prospectively for 7 years and all fractures sustained were recorded. Prospectively, for a 1 SD decrease in forearm BMD, the Cox proportional hazard model gave a relative risk (RR) of 1.75 with a 95% confidence interval of 1.08-2.83 for a forthcoming fracture and 3.88 (1.30-11.57) for a hip fracture. For a 1 SD change in skinfold thickness, measured on the dorsum of the hand, a RR of 1.69 (0.99-2.87) for a forthcoming fracture was found and the corresponding value for hip fracture was 2.34 (1.10-5.00). Testosterone and SHBG did not enhance fracture prediction. Abusers of alcohol had, retrospectively, significantly more fractures. Individuals with alcohol consumption rates in the highest quartile had significantly higher CDT levels, but we were unable to identify high consumers of alcohol by analyzing BMD or sex hormones. In this study we found that forearm BMD and skinfold thickness could be used in predicting forthcoming fractures in men.

Aged↗
PubMed1998

Balance and gait performance in an urban and a rural population.

OBJECTIVE: To compare the differences in standing balance and gait performance between two populations, correlated with age and physical activities of daily living. DESIGN: A cross-sectional study. SETTINGS: Malmö, the third largest city in Sweden, and Sjöbo, a typical agricultural community 60 km east of Malmö. PARTICIPANTS: Participants were 570 men and women from the urban community (urban) and 391 from the rural community (rural), born in 1938, 1928, 1918, and 1908, and women born in 1948. The two cohorts were subdivided into true urbans, who had lived only in the city (n = 269), and true rurals, who had never lived in a city (n = 354). MEASUREMENTS: Information about workload, housing, spare time activities, medication, and illness during different decades of life was gathered using two questionnaires. The first questionnaire was sent to the home after agreement to participate, and the second was presented at the test session. The clinical measurements were standing balance, gait speed, and step length. RESULTS: The urban subjects had significantly (P < .001) impaired balance compared with rural subjects. This difference increased with increasing age. The urban subjects walked faster than the rural subjects (P < .001), and the urban subjects used fewer steps than their rural counterparts (P < .001). Spare time activities had a significant influence on the above tests, but, except for gait velocity (P = .011), workload was of minor importance according to analysis of covariance. CONCLUSION: Background factors such as usual daily activities of living and lifestyle seem to be of importance when evaluating and comparing different populations with respect to their balance and gait performance.

Adult↗
PubMed1998

How well can a previous fracture indicate a new fracture? A questionnaire study of 29,802 postmenopausal women.

In a population-based, retrospective study, we investigated the effect of a previous fracture on the risk of a later fracture. A questionnaire was mailed to 46,353 postmenopausal women aged 50-80 years and 29,802 (64%) responded. Questions were asked about fractures after age 25 and in what year they had occurred. The fractures were grouped according to whether they occurred within 5 and 10 years before answering the questionnaire. The occurrence of a fracture preceding these time intervals increased the odds ratio (OR) of having sustained a hip fracture to 1.6 (95% CI 1.1-2.3) for a previous ankle fracture and to 3.5 (95% CI 2.4-5.0) for a previous humerus fracture. Corresponding figures for having sustained a spine fracture were 1.5 (95% CI 1.1-2.1) for a previous ankle fracture and 4.5 (95% CI 3.4-5.9) for a previous spine fracture. It seems possible to select women for evaluation and intervention against osteoporosis by using information on previous fragility fractures.

Age Distribution↗
PubMed1998

Bone mineral density assessed by quantitative ultrasound and dual energy X-ray absorptiometry. Normative data in Malmö, Sweden.

We measured bone mineral density (BMD) in 128 men and 143 women, aged 22-90, by dual energy X-ray absorptiometry (DEXA) and quantitative ultrasound (QUS). We found reduced bone mineral density in relation to age as measured both by DEXA and QUS. There was a correlation between 0.28 and 0.52 in men and between 0.53 and 0.77 in women when comparing DEXA and QUS measurements. When including only persons with low bone mass, the correlation was less.

Absorptiometry, Photon↗
PubMed1997

The socioeconomic burden of fractures: today and in the 21st century.

Hip fractures are a burden to both the individual and the community. Only 50% of patients regain the mobility and independence they enjoyed 12 months before the hip fracture occurred. Direct costs are high: about US$7,000 for the immediate hospital care and $21,000 in total costs for the first year. The numbers of hip fractures worldwide are projected to increase from 1.7 million in 1990 to 6.3 million in 2050 because of the aging of the population; therefore, the total cost of these fractures will also increase. Based on today's currency values and a cost of $21,000 per patient, the total cost of hip fractures in the year 2050 will be $131.5 billion. The costs and morbidity associated with other fractures, such as vertebral fractures, are less well defined. Because hip fractures are associated with the highest and most well-defined costs, morbidity, and mortality of all fragility fractures, models with high sensitivity can now be devised for evaluating the costs and benefits of interventions. These models are constructed using data on incidence, morbidity, mortality, and costs of fractures, along with the efficacy of an intervention, to estimate the impact of that intervention against osteoporosis. According to one model, the cost per hip fracture avoided is $48,600 if a 62-year-old woman with osteoporosis receives treatment with a drug that is administered for 5 years at $830/year and produces a 50% reduction in fracture rate. The cost per life-year saved is $30,600, and the cost per quality-adjusted life-year is $14,900. By comparison, using this model, treatment of a 62-year-old woman with a diastolic pressure of 95 mm Hg using a drug costing $420/year that reduces risk of stroke by 38% results in costs of $144,200 per stroke avoided, $17,800 per life-year saved, and $14,300 per quality-adjusted life-year. Health economic models allow for changes in assumptions, such as extent of compliance, effectiveness of therapy, and risk of side effects. Cost-effectiveness varies according to treatment and is highly sensitive to the estimated efficacy of treatment, patient compliance, age of the patient at the start of treatment, and fracture risk assigned to the patient. Greater cost-effectiveness occurs when treatments are more efficacious and when they are directed at patients with the highest risk of fracture.

Cost Savings↗
PubMed1997

Anthropometric measurements and vertebral deformities. European Vertebral Osteoporosis Study (EVOS) Group.

To investigate the association between anthropometric indices and morphometrically determined vertebral deformity, the authors carried out a cross-sectional study using data from the European Vertebral Osteoporosis Study (EVOS), a population-based study of vertebral osteoporosis in 36 European centers from 19 countries. A total of 16,047 EVOS subjects were included in this analysis, of whom 1,973 subjects (915 males, 1,058 females) (12.3%) aged 50 years or over had one or more vertebral deformities ("cases"). The cases were compared with the 14,074 subjects (6,539 males, 7,535 females) with morphometrically normal spines ("controls"). Data were collected on self-reported height at age 25 years and minimum weight after age 25 years, as well as on current measured height and weight. Body mass index (BMI) and height and weight change were calculated from these data. The relations between these variables and vertebral deformity were examined separately by sex with logistic regression adjusting for age, smoking, and physical activity. In females, there was a significant trend of decreasing risk with increasing quintile of current weight, current BMI, and weight gain since age 25 years. In males, subjects in the lightest quintile for these measures were at increased risk but there was no evidence of a trend. An ecologic analysis by country revealed a negative correlation between mean BMI and the prevalence of deformity in females but not in males. The authors conclude that low body weight is associated with presence of vertebral deformity.

Age Factors↗
PubMed1997

Population-based geographic variations in DXA bone density in Europe: the EVOS Study. European Vertebral Osteoporosis.

The purpose of this study was to investigate variations in bone density between 16 European populations, 13 of which were participants in the European Vertebral Osteoporosis Study (EVOS). Men and women aged 50-80 years were recruited randomly from local population registers, stratified in 5-year age bands. The other three centres recruited similarly. Random samples of 20-100% of EVOS subjects were invited for dual-energy X-ray absorptiometry (DXA) densitometry of the lumbar spine and/or proximal femur using Hologic, Lunar or Norland pencil beam machines or, in one centre, a Sopha fan-beam machine. Cross-calibration of the different machines was undertaken using the European Spine Phantom prototype (ESPp). Highly significant differences in mean bone density were demonstrated between centres, giving rise to between centre SDs in bone density that were about a quarter of a population SD. These differences persisted when centres using Hologic machines and centres using Lunar machines were considered separately. The centres were ranked differently according to whether male or female subjects were being considered and according to site of measurement (L2-4, femoral neck or femoral trochanter). As expected, bone mineral density (BMD) had a curvilinear relationship with age, and apparent rates of decrease slowed as age advanced past 50 years in both sexes. In the spine, not only did male BMD usually appear to increase with age, but there was a highly significant difference between centres in the age effect in both sexes, suggesting a variability in the impact of osteoarthritis between centres. Weight was consistently positively associated with BMD, but the effects of height and armspan were less consistent. Logarithmic transformation was needed to normalize the regressions of BMD on the independent variates, and after transformation, all sites except the femoral neck in females showed significant increases in SD with age. Interestingly, the effect of increasing weight was to decrease dispersion in proximal femur measurements in both sexes, further accentuating the tendency in women for low body mass index to be associated with osteoporosis as defined by densitometry. It is concluded that there are major differences between BMD values in European population samples which, with variations in anthropometric variables, have the potential to contribute substantially to variations in rates of osteoporotic fracture risk in Europe.

Absorptiometry, Photon↗
PubMed1997

Quality of life as outcome in the treatment of osteoporosis: the development of a questionnaire for quality of life by the European Foundation for Osteoporosis.

The morbidity of osteoporosis is caused by fractures. Vertebral fractures lead to pain and disability and a decrease in quality of life. A Working Party of the European Foundation for Osteoporosis has developed a specific questionnaire for patients with established vertebral osteoporosis. This questionnaire is intended for use in clinical trials. The questionnaire consists of questions and visual analogue scales in the following domains: pain, activities of daily living, jobs around the house, mobility, leisure and social activities, general health perception and mood. The questionnaire has been translated from English into French, German, Italian, Hebrew, Swedish and Dutch. The questionnaire is currently being validated in a multicentre study involving patients with stable osteoporosis and control subjects. Preliminary results indicate that the reproducibility is sufficient and that the questionnaire is able to discriminate between patients with vertebral osteoporosis and control subjects.

Activities of Daily Living↗
PubMed1997

The hospital burden of vertebral fracture in Europe: a study of national register sources.

The aims of this study were to quantify the hospital burden of vertebral fracture in Europe and to compare this with that of hip fracture. Information on hospital discharges was sought by age and sex from Ministries of Health in Europe. Discharge rates for vertebral fracture, available from 12 countries, varied by more than 4-fold between countries, which was greater than the differences between sexes. Where the discharge rate was high for vertebral fracture the incidence of hip fracture was also high. Since nearly all cases of hip fracture are hospitalized, this suggests a relationship between hip and vertebral fracture risk that is not explained by different admission policies for vertebral fractures European countries.

Age Factors↗
PubMed1997

World-wide projections for hip fracture.

The aims of this study were to estimate the present and future incidence of hip fracture world-wide. From a survey of available data on current incidence, population trends and the secular changes in hip fracture risk, the numbers of hip fractures expected in 2025 and 2050 were computed. The total number of hip fractures in men and women in 1990 was estimated to be 338,000 and 917,000 respectively, a total of 1.26 million. Assuming no change in the age- and sex-specific incidence, the number of hip fractures is estimated to approximately double to 2.6 million by the year 2025, and 4.5 million by the year 2050. The percentage increase will be greater in men (310%) than in women (240%). With modest assumptions concerning secular trends, the number of hip fractures could range between 7.3 and 21.3 million by 2050. The major demographic changes will occur in Asia. In 1990, 26% of all hip fractures occurred in Asia, whereas this figure could rise to 37% in 2025 and to 45% in 2050. We conclude that the socioeconomic impact of hip fractures will increase markedly throughout the world, particularly in Asia, and that there is an urgent need to develop preventive strategies, particularly in the developing countries.

Age Distribution↗
PubMed1997

A single bone density measurement can predict fractures over 25 years.

The purpose of the present study was to determine the predictive ability of a single bone mineral density (BMD) measurement on a 25-year perspective. A group of 1076 women (age 20-78 years) had had their forearm BMD measured from 1970 to 1975. In those women that were still alive at the end of 1994 (n = 410), all fragility fractures (distal end of the radius, proximal end of the humerus, hip, and vertebra) that had occurred after the BMD measurement and that were roentgen verified were recorded, after a follow-up time of 20-25 years. Altogether, 213 fractures occurred in the cohort. In the age group > or = 40-70 (at time of BMD measurement) the relative risk (RR) associated with a 1 SD decrease of forearm BMD was 1.66 (CI 1.13-2.46) for a hip fracture (n = 43), 1.79 (CI 1.22-2.62) for a vertebral fracture (n = 63), and 1.33 (CI 1.20-1.73) for all fractures. In the age group 30-50, a fracture of the distal end of the radius after 20 years could be predicted; RR 1.90 (CI 1.02-3.55). These are slightly lower predictive values compared with previous studies of the same population with follow-up times of 11 and 13 years, especially with regard to hip fractures. However, the present study demonstrates that a single BMD measurement at the forearm has a predictive ability for fragility fractures--including hip fractures--on a 25-year perspective.

Adult↗
PubMed1997

The relationship between childhood growth, bone mass, and muscle strength in male and female adolescents.

In this population-based study, the relationship between childhood weight and height, and adolescent bone mass and muscle strength have been studied in 39 girls and 48 boys. Total body and femoral neck bone mass measurements (bone mineral content, BMC and bone mineral density, BMD) were made by dual X-ray absorptiometry. Quadriceps muscle strength was measured. Mean age at the time of measurement was 15.1 years for girls and boys. Results were individually linked to data on childhood (birth to 6 years of age) weight and height, taken from community health records. Childhood weight was found to be predictive of adolescent total body BMC (TBMC). However, this was not the case when correlating childhood weight and total body BMD (TBMD), suggesting that growth determines the size of the skeleton, whereas the density within that bone envelope is to a greater extent governed by other factors. Further, in a multiple regression model we found that the combined effect of childhood weight and height was significantly correlated with adolescent quadriceps muscle strength.

Absorptiometry, Photon↗
PubMed1997

Bone graft incorporation after cortical perforations of the host bed.

A fundamental issue in onlay bone graft persistence is the unpredictable extent of incorporation and volumetric maintenance of the graft. The purpose of this study was to evaluate the effects on integration of onlays, with either their cancellous or cortical portion facing toward the host bed, positioned over cortical perforations at the recipient site. Tibial or femoral unicortical bone grafts were harvested from isogeneic donors and positioned subperiostally on each tibia of 22 adult Lewis rats. On the experimental side, the recipient outer cortical bone surface received multiple perforations, 0.25 mm in diameter. The contralateral side served as a control (no cortical perforations). The findings were assessed after 4 and 20 weeks using routine histologic and immunohistochemistry techniques. Cortical perforations induced a migration of the recipient bone marrow into the graft as well as a reduced size diminution. More cortical bone remodeling and marginal lamellar bone apposition were observed after orientating the cortical portion of the graft toward the recipient site. These observations may be useful clinically to improve long-term success after autogeneic bone grafting.

Animals↗
PubMed1997

What is the impact of osteoporosis?

A body of evidence points towards a close connection between susceptibility to fractures and osteoporosis. The incidence of osteoporotic fractures, both in absolute figures and in age-specific figures, has increased worldwide throughout this century. Although some reports show that the age-specific incidence is levelling-off, there will be a continuously increasing number of individuals with such fractures that will have implications from an economical point of view not only for the affected individual but for society as a whole. The outcome after such fractures, especially those of the hip, is by no means always favourable, partly due to insufficient results after orthopaedic treatment and partly due to an already high comorbidity. Therefore, trying to prevent osteoporotic fractures by non-pharmacological or pharmacological regimens is of utmost importance.

Aged↗
PubMed1997

The natural course of arthrosis of the knee.

The aim of this study was to describe the course of untreated or conservatively treated arthrosis of the knee joint. Of 265 patients presenting with knee pain who had weightbearing radiographs taken between 1970 and 1973, 132 (33 men and 99 women) responded to and participated in a clinical followup 20 years later using the Hospital for Special Surgery score and new weightbearing radiographs. Arthrosis was defined as an equal to or greater than 50% joint space narrowing. In 75 of 132 knees of Ahlbäck Class 0 (57%) and 20 of 52 knees of Ahlbäck Class I (39%), the classification remained unchanged. The Hospital for Special Surgery score at followup was compared with the Ahlbäck classes in the 1970s for the 110 cases for which surgery was not done. A higher Ahlbäck class at the time of presentation was associated with lower functional score (Hospital for Special Surgery) 20 years later. In addition, in the contralateral knee a reduction of joint space may occur. In the arthrosis group with total joint space reduction or attrition there was a clinical and radiographic deterioration that would merit surgical intervention to avoid unnecessary loss of function. However, in knees with equal to or greater than 50% joint space reduction (Ahlbäck I) and pain, a considerable number (39%) did not deteriorate radiographically during a 20-year period, and 25% remain free of pain. It appears that the long-term prognosis of mild knee arthrosis is not necessarily poor. A substantial number of these patients will not have progression of the arthrosis.

Adult↗