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H Mallmin

Publications and source records attributed to H Mallmin.

At least 37 records · Page 2Linked to original sources

Low body mass index and use of corticosteroids, but not cholestasis, are risk factors for osteoporosis in patients with chronic liver disease.

BACKGROUND/AIMS: Metabolic bone disease is known to complicate chronic liver disease. In a cross-sectional, controlled study we have studied the prevalence of osteoporosis in patients with various types of chronic liver disease. We also identified risk factors predisposing to osteoporosis in this patient group. METHODS: Seventy-two hospitalised patients, 46 females and 26 males, were included. Age- and sex-matched individuals from the background population served as controls. Bone mineral density was measured by dual energy X-ray absorptiometry at the lumbar spine and femoral neck. RESULTS: Bone mineral density was significantly lower in patients with chronic liver disease than in controls at the lumbar spine (Z-score: -0.35 SD+/-1.36 vs. 0.26 SD+/-1.19, p<0.01) but not at the femoral neck (Z-score: -0.18 SD+/-1.48 vs. 0.17 SD+/-1.08, NS). Patients with cholestatic chronic liver disease did not have lower bone mineral density compared with patients with non-cholestatic chronic liver disease (Z-score: -0.35 SD+/-1.30 vs. -0.34 SD+/-1.45). Osteoporosis was found in 30% of the patients and 15% of the controls, respectively. In a multivariate regression analysis on risk factors in the patient group, the following factors were associated with osteoporosis: use of corticosteroids (odds ratio=18.9; p<0.01), low body mass index (odds ratio=14.1; p=0.001), high age and female sex. CONCLUSION: Patients with chronic liver disease are at risk of developing osteoporosis. Risk factors for osteoporosis in chronic liver disease are low body mass index and corticosteroid therapy, in addition to high age and female sex. Cholestatic liver disease per se is not associated with an increased risk for osteoporosis.

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Differences in whole body measurements by DXA-scanning using two Lunar DPX-L machines.

OBJECTIVE: To compare bone mineral and body composition results of two dual-energy X-ray absorptiometry (DXA) instruments from the same manufacturer. SETTINGS: The Medical departments of Sahlgrenska University Hospital, Göteborg and University Hospital, Uppsala, Sweden. DESIGN: Unique aluminium spine phantoms (Phant A and B) delivered with each DXA machine (DXA-A and DXA-B) were cross-checked on the other machine by using the 'AP spine mode'. Eight adolescents were examined on both instruments within 5 h to ascertain total body variables by using standard, as well as extended, modes of analysis. All these double-examinations were undertaken on two occasions, before and after exchange of a detector on the DXA-B. SUBJECTS: Four males and four females aged 15.4-19.2 y with normal body weights, were examined on both occasions. On each occasion, the first examination was performed in Göteborg on four individuals and in Uppsala on four individuals. RESULTS: On the first occasion the phantom measurements resulted in much lower bone mineral density (BMD) values on the DXA-B than on the DXA-A. Later it was detected that a so-called R-value and the corresponding '%-fat' value were out of range on the DXA-B. After exchange of detector, the difference in phantom BMD-values between the two machines had diminished. On the first occasion in vivo BMD values were lowest on the DXA-B (P < 0.01), while on the second occasion they were significantly lower on the DXA-A (P < 0.05). Soft tissue differences were greater after detector exchange and as compared to DXA-A, DXA-B underestimated body fat by 3.5 kg (13.2 vs 9.7 kg, P < 0.001) and overestimated lean tissue mass by 3.8 kg (47.1 vs 50.9 kg, P < 0.001) on the second occasion. CONCLUSIONS: The differences in results between two apparently identical Lunar DPX-L machines were not acceptable. In multicenter studies, it may be necessary to standardise results of participating machines into results of one machine by means of regression equations obtained by examining subsamples of individuals on one master machine and other participating instruments.

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Stability assessment of a moderately conforming all-polyethylene tibial component in total knee arthroplasty: a prospective RSA study with 2 years of follow-up of the Kinemax Plus design.

The magnitude and pattern of the migration of an all-polyethylene tibial component with moderately conforming articular surfaces in total knee arthroplasty was analyzed in 20 patients > or =60 years during a 2-year follow-up using radiostereometry (RSA). Most of the migration occurred during the initial 4 months, whereafter the migration diminished, reaching a mean maximum migration of 0.75 mm at 2 years. Similar patterns were found for rotation of the implant. Maximum subsidence at 2 years was 0.7 mm and was most commonly located at the posteromedial part of the tibial component. These results indicate that an all-polyethylene tibial component with moderately conforming articular geometry and with a thickness of 10-12 mm demonstrated migration patterns compatible with a favorable prognosis in regard to future aseptic loosening.

Aged↗

Excessive dietary intake of vitamin A is associated with reduced bone mineral density and increased risk for hip fracture.

BACKGROUND: The highest incidence of osteoporotic fractures is found in northern Europe, where dietary intake of vitamin A (retinol) is unusually high. In animals, the most common adverse effect of toxic doses of retinol is spontaneous fracture. OBJECTIVE: To investigate whether excessive dietary intake of vitamin A is associated with decreased bone mineral density and increased risk for hip fracture. DESIGN: A cross-sectional study and a nested case-control study. SETTING: Two counties in central Sweden. PARTICIPANTS: For the cross-sectional study, 175 women 28 to 74 years of age were randomly selected. For the nested case-control study, 247 women who had a first hip fracture within 2 to 64 months after enrollment and 873 age-matched controls were selected from a mammography study cohort of 66,651 women 40 to 76 years of age. MEASUREMENTS: Retinol intake was estimated from dietary records and a food-frequency questionnaire. Bone mineral density was measured with dual-energy x-ray absorptiometry. Hip fracture was identified by using hospital discharge records and was confirmed by record review. RESULTS: In multivariate analysis, retinol intake was negatively associated with bone mineral density. For every 1-mg increase in daily intake of retinol, risk for hip fracture increased by 68% (95% CI, 18% to 140%; P for trend, 0.006). For intake greater than 1.5 mg/d compared with intake less than 0.5 mg/d, bone mineral density was reduced by 10% at the femoral neck (P = 0.05), 14% at the lumbar spine (P = 0.001), and 6% for the total body (P = 0.009) and risk for hip fracture was doubled (odds ratio, 2.1 [CI, 1.1 to 4.0]). CONCLUSION: High dietary intake of retinol seems to be associated with osteoporosis.

Adult↗

Relationships between bone mass measurements and lifetime physical activity in a Swedish population.

Lifetime occupational and leisure time activities were assessed by a questionnaire in order to evaluate their relationship to bone mass measurements and biochemical markers of bone metabolism in a population of 61 women and 61 men, randomly selected from a Swedish population register, to represent ages between 22 and 85 years. We also considered possible confounders by using questions about smoking habits, milk consumption, hormone replacement therapy (HRT), and menopausal age. Bone mineral density (BMD) and bone mineral content (bone mass, BMC) of the total body, lumbar spine, and proximal femur (neck, trochanter, Ward's triangle) were measured by dual energy X-ray absorptiometry (DXA), and BMD of the forearm with single energy X-ray absorptiometry (SXA). In addition, both DXA and SXA provided information on bone area. Quantitative ultrasound measurements (QUS) at the heel were performed to assess the speed of sound (SOS) and broadband ultrasound attenuation (BUA). Fasting blood samples were analyzed for biochemical markers of bone metabolism as well as parathyroid hormone (PTH) and total serum calcium. After adjustment for confounding factors, neither BMD nor QUS measurements were consistently related to lifetime leisure time or occupational activities; nor were there any consistent patterns relating biochemical markers of bone metabolism to bone mass measurements. However, physical activity seemed to influence bone mass, area, and width more than density. In men, high levels of leisure time activity were associated with raised values for lumbar spine area (6.2%) and width (3.3%) as well as for femoral neck area (5.5%) compared with their low activity counterpart. Men exposed to high levels of occupational activity demonstrated lower lumbar spine BMD (10.9%) and area (5.3%) than men with low activity levels. Within an unselected Swedish population, estimation of lifetime occupational and sport activities as well as bedrest, using a questionnaire, demonstrated no major effects on bone density. However, the association between high levels of lifetime activity and raised values for bone mass, area, and width indicate that geometrical changes in bone may provide better estimations of mechanically induced bone strength than bone density, at least in men.

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Oral isotretinoin therapy in severe acne induces transient suppression of biochemical markers of bone turnover and calcium homeostasis.

Although dietary vitamin A is required for normal growth and development, long-term or high-dose administration of vitamin A derivatives (retinoids) may produce a variety of skeletal side-effects in man. In this study we investigated the early effects of oral isotretinoin therapy on bone turnover and calcium homeostasis in eleven consecutive patients with nodulocystic acne. The effects on bone metabolism were correlated to radiological and bone mineral density measurements following drug therapy for six months. Markers of bone turnover, i.e. serum osteocalcin, the carboxyterminal propeptide of type I collagen, bone specific alkaline phosphatase, the carboxyterminal telopeptide of type I collagen, and urine levels of calcium and hydroxyproline decreased significantly within five days of treatment (p < 0.05). There was also a statistically significant decrease in serum calcium, with a minimum on day five, and a marked increase in serum parathyroid hormone (p < 0.05). With continued treatment, however, the abnormal levels of these markers returned to baseline values within 14 days. No significant roentgenological changes or effects on bone mineral density were found in response to the drug. The observed inhibitory effects of isotretinoin on bone turnover, despite elevated parathyroid hormone levels, indicates that the drug exerts a direct effect on bone tissue.

Acne Vulgaris↗

An evaluation of dual-energy X-Ray absorptiometry and underwater weighing to estimate body composition by means of carcass analysis in piglets.

To evaluate the use of dual-energy X-ray absorptiometry (DXA) and underwater weighing (UWW) for body-composition measurements, the carcasses of eight piglets (12-wk old, 15-22 kg in weight) were dissected into muscle, fat and bone. Thereafter, the components were homogenized and chemically analyzed for fat and bone mineral mass. Body components as measured by DXA correlated closely to the carcass analysis (r = 0.90-1.0). However, DXA still overestimated significantly the bone mineral mass, lean mass and total weight, and underestimated fat mass. The reproducibility of measurements, expressed as the CV for fat mass was 13.5%, whereas for total weight, lean mass and bone mineral mass, the CV was 0.74-1.9%. Fat mass was overestimated by UWW using the equations of Siri or Kraybill (r = 0. 77), but not by the equation of Lohman et al. (r = 0.69). The difference between the estimation of fat by chemical analysis and estimations by DXA and UWW was significantly affected by the amount of water in lean mass and fat-free mass.

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Postoperative drainage of knee arthroplasty is not necessary: a randomized study of 90 patients.

We studied the management of postoperative drainage after total knee replacement (TKR). 90 primary total knee joint arthroplasties were prospectively randomized into 3 groups: a) no drain, b) an autotransfusion system, c) a standard disposable closed suction drainage system. We monitored hemoglobin and hematocrit values, drainage volume and transfusions (homologous and autologous), range of knee motion, knee swelling and hospital stay. Parameters were recorded preoperatively, days 0-8 and 4 months postoperatively. No significant differences were seen between the groups in any of the parameters measured. The results show no benefit from using postoperative drainage systems in knee arthroplasties. Savings of SEK 400 (USD 55) per patient would have resulted if drains had not been used at all.

Aged↗

Case-control study on symptoms and signs of "asymptomatic" primary hyperparathyroidism.

BACKGROUND: Symptoms, signs, and treatment of mild primary hyperparathyroidism (HPT) are controversial. METHODS: One hundred two patients with HPT and matched controls were recruited from 5202 females attending population-based mammography screening at age 55 to 75 years. Patients' total serum calcium averaged 10.40 +/- 0.564 mg/dL and intact serum parathyroid hormone 58 +/- 33 ng/L. All patients lacked knowledge of their disease. Questions revealed traditional symptoms of HPT in 24% of cases and 43% of controls (P = .01). All individuals underwent the same biochemical analyses, bone mass determination, and questionnaires on symptoms, illnesses, medications, and background variables. RESULTS: Patients with HPT had more psychic complaints (P = .03 to .007) of lassitude, fatigue, irritability, and lack of sexual and emotional interests. They had lower bone density in total body, spine, and hip (P = .008 to .0004) and higher serum alkaline phosphatase, cholesterol (very-low-density lipoprotein), triglycerides (total, very-low-density lipoprotein), glucose, urate, and hemoglobin values (P = .02 to .0001). Patients visited physicians more often (P = .008) and had more antihypertensive therapy (P = .02). CONCLUSIONS: Mild, "asymptomatic" HPT in patients unaware of their disorder displays significant psychic symptoms, bone loss, and risk factors of cardiovascular disease.

Aged↗

A high dietary calcium intake is needed for a positive effect on bone density in Swedish postmenopausal women.

The importance of dietary calcium for bone health is unclear, partly since most investigations have dealt only with a fairly narrow range of calcium intake. In the present population-based observational study with longitudinal dietary assessment, we investigated women with a mean age of 60 years and with a consistently high (range 1417-2417, mean 1645 mg, n = 40), intermediate (800-1200, mean 1006 mg, n = 35) or low (400-550, mean 465 mg, n = 40) estimated daily consumption of calcium. Measurements of bone mineral density (BMD) of the lumbar spine, femoral neck and total body were performed by dual-energy X-ray absorptiometry, as well as ultrasound of the heel. In a multivariate analysis, with adjustment for energy intake the risk factors for osteoporosis (age, body mass index, physical activity, menopausal age, use of estrogens, smoking and former athletic activity), the group with the highest calcium intake had higher values for BMD than the others at all measured sites. The average mean difference compared with the low and the intermediate calcium group was 11% for the femoral neck, 8-11% for the lumbar spine and 5-6% for total body BMDs. In univariate analyses and multivariate models which did not include energy intake, the differences between the groups were less pronounced. The women in the intermediate calcium group had approximately the same mean BMD values as those in the low calcium group. These findings support the view that only a high calcium intake (3% highest percentiles in the studied population) protects against osteoporosis in Swedish postmenopausal women.

Adult↗

Bone metabolism in endurance trained athletes: a comparison to population-based controls based on DXA, SXA, quantitative ultrasound, and biochemical markers.

In general, physical exercise appears to have favorable effects on the skeleton. However, a few recent reports have described negative effects, including reduced bone density (BMD) and high bone turnover in runners. The aim of our study was to compare endurance runners to controls with respect to BMD at different sites and ultrasound transmission through the peripheral skeleton, and to use PTH, total serum calcium, and biochemical markers of bone metabolism as a complement in evaluating the effects of endurance running on bone. Thirty runners (mean age 32 years, range 19-54 years) participated in the study. Their main form of training consisted of endurance running at moderate intensity for about 7 hours (range 2-12 hours) per week, and they had been active in their sport for about 12 years (range 1-21 years). For a comparison, 30 age- and sex-matched population based controls were investigated. BMD values, measured by dual energy X-ray absorptiometry (DXA), were higher in runners than in controls for the total body (3.6%; P = 0.03), legs (9.6%; P = 0. 001), femoral neck (10.0%; P = 0.01), trochanter (9.9%; P = 0.01), and Wards triangle (11.8%; P = 0.02), but not in the lumbar spine or in the forearm measured by single energy X-ray absorptiometry (SXA). The quantitative ultrasound measurement of the calcaneus also revealed higher values in runners than in controls for both broadband ultrasound attenuation (9.2%; P = 0.002) and speed of sound (3.1%; P = 0.0001). At all sites, BMD was related to ultrasound measurements in controls, but no such relationship was evident in runners. Concentrations of parathyroid hormone (PTH) were lower (23.2%; P = 0.02) in runners than in controls, whereas total serum calcium concentrations were slightly higher (3.0%; P = 0.003). The levels of PICP (bone formation) and ICTP (bone resorption) in serum were lower (18.0%; P = 0.03 and 22.2%; P = 0.004, respectively) in runners than in controls, but no differences were seen for osteocalcin or bone specific alkaline phosphatase (b-ALP). In conclusion, BMD at the focus of strain for running, that is, the legs, is higher in endurance runners when compared to matched controls. Low bone turnover in runners, indicated by lower levels of PTH and biochemical markers of bone metabolism, point to an influence of endurance running at the cellular level.

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Proportional changes in body fluid with hemodialysis evaluated by dual-energy X-ray absorptiometry and transthoracic bioimpedance with particular emphasis on the thoracic region.

Alterations in body composition during extracorporeal hemodialysis (HD) were investigated in 12 hemodialysis patients (9 males and 3 females, mean age 50 +/- 15 years) with a mean ultrafiltration of 2.6 +/- 1.0 L. Analysis was performed using a dual-energy x-ray absorptiometry technique (DXA), which measures 3 principal components of the body: fat mass (FM): lean body mass (LBM), i.e., all soft tissues excluding fat; and bone mineral content (BMC). These 3 components were calculated for the whole body and for different body regions (namely, the thorax, trunk, lower limbs, and upper limbs). The thoracic cage region could be defined manually, separately from the trunk, and its tissue composition was calculated. DXA analysis was performed concomitant with a measurement of the basal thoracic impedance (TFI) by bioimpedance cardiography prior to and 1 h after dialysis. We found a significant decrease in the total LBM, from 55.8 +/- 8.8 to 53.3 +/- 9.3 kg (p < 0.05), but no change in either the FM or BMC. Moreover, there was a disproportional reduction in the LBM in different regions, being significantly greater in the thorax (7.47 +/- 3.7%) than in the other body regions (trunk 4.3 +/- 2.0%, lower limbs 5.4 +/- 2.1%, and upper limbs 4.7 +/- 1.5%). Regarding bioimpedance, a stronger significant correlation was detected between the percentage changes in the TFI and the changes in thoracic fluid (r = 0.80, p < 0.01) than between the changes in the TFI and the changes in the total body fluid (r = 0.63, p < 0.01). The absolute values of the TFI were also significantly and negatively correlated to the thoracic lean mass to fat mass ratio, both before and after HD (r = 0.82, p < 0.001 and r = 0.86, p < 0.001, respectively). In conclusion, DXA is a very sensitive technique to detect fluid changes during HD in the thorax when the thoracic cavity is defined as a region of interest as well as for the whole body. The data also indicate an extracellular compartmental imbalance between different regions with a significantly greater change in the thoracic region. Transthoracic bioimpedance is a useful technique for evaluating the HD induced changes in the thoracic fluid, rather than total body fluid.

Absorptiometry, Photon↗

Aluminum, Alzheimer's disease and bone fragility.

The incidence of fragility fractures has increased epidemically. Especially patients with senile dementia (including Alzheimer's disease) have a greatly increased risk of fragility fractures. Aluminum inhibits bone mineralization; the greater the aluminium exposure, the higher the risk of an early fracture. Aluminium is neurotoxic and may, in addition to genetic factors, play a role in the development of Alzheimer's disease by contributing to the formation of the characteristic beta-amyloid and neurofibrillary tangles. Thus, a common denominator between Alzheimer's disease and bone fragility may be a chronic low-grade aluminum intoxication. The epidemic of fragility fractures may be caused by increased aluminium exposure--due to the use of aluminum cooking pots or the pollution acidification of our environment. In our pilot study of 26 hip-fracture patients (13 patients with Alzheimer's disease and 13 individually age- and gender-matched non-demented patients), the aluminum content, determined mass-spectro-metrically, was higher in trabecular bone biopsies from the patients with Alzheimer's disease than from the non-demented patients (p = 0.005). The aluminum content was also higher in the younger of the 26 patients (p = 0.02). Our findings agree with the hypothesis that aluminum plays a role in the development of Alzheimer's disease and bone fragility.

Aged↗

Screening for osteopenia and osteoporosis: selection by body composition.

There is a great need for simple means of identifying persons at low risk of developing osteoporosis, in order to exclude them from screening with bone mineral measurements, since this procedure is too expensive and time-consuming for general use in the unselected population. We have determined the relationships between body measure (weight, height, body mass index, lean tissue mass, fat mass, waist-to-hip ratio) and bone mineral density (BMD) in 175 women of ages 28-74 years in a cross-sectional study in a county in central Sweden. Dual-energy X-ray absorptiometry was performed at three sites: total body, L2-4 region of lumbar spine, and neck region of the proximal femur. Using multiple linear regression models, the relationship between the dependent variable, BMD, and each of the body measures was determined, with adjustment for confounding factors. Weight alone, in a multivariate model, explained 28%, 21% and 15% of the variance in BMD of total body, at the lumbar spine and at the femoral neck according to these models. The WHO definition of osteopenia was used to dichotomize BMD, which made it possible, in multivariate logistic regression models, to estimate the risk of osteopenia with different body measures categorized into tertiles. Weight of over 71 kg was associated with a very low risk of being osteopenic compared with women weighing less than 64 kg, with odds ratios (OR) of 0.01 (95% confidence interval (CI) 0.00-0.09), 0.06 (CI 0.02-0.22) and 0.13 (CI 0.04-0.42) for osteopenia of total body, lumbar spine and femoral neck, respectively. Furthermore a sensitivity/specificity analysis revealed that, in this population, a woman weighing over 70 kg is not likely to have osteoporosis. Test specifics of a weight under 70 kg for osteoporosis (BMD less than 2.5 SD compared with normal young women) of femoral neck among the postmenopausal women showed a sensitivity of 0.94, a specificity of 0.36, positive predictive value (PPV) of 0.21, and negative predictive value (NPV) of 0.97. Thus, exclusion of the 33% of women with the highest weight meant only that 3% of osteoporotic cases were missed. The corresponding figures for lumbar spine were sensitivity 0.89, specificity 0.38, PPV 0.33, and NPV 0.91. All women who were defined as being osteoporotic of total body weighed under 62 kg. When the intention was to identify those with osteopenia of total body among the postmenopausal women we attained a sensitivity of 0.92 and a NPV of 0.91 for a weight under 70 kg, whereas we found that weight could not be used as an exclusion criterion for osteopenia of femoral neck and lumbar spine. Our data thus indicate that weight could be used to exclude women from a screening program for postmenopausal osteoporosis.

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Effect of prefracture versus postfracture dietary assessment on hip fracture risk estimates.

BACKGROUND: Dietary factors are presumed to have influence on bone mass and hence fracture susceptibility. Most information in this respect is based on retrospective assessment of previous dietary habits. In a population-based case-control study nested within a cohort, we collected dietary information both before and after a first hip fracture. Thus it was possible to study reported changes in dietary habits, intentional as well as unintentional, among hip fracture patients after a first hip fracture and to compare postfracture with prefracture dietary information. METHODS: More than 65 000 women born 1914-1948 in two counties in central Sweden completed a food frequency questionnaire regarding their usual current dietary habits, before attending a mammographic screening between the years 1987 and 1990. Subsequently 123 of them sustained a first hip fracture and were defined as cases in the present study. For every case, one control, individually matched by age and county of residence, was selected from the cohort. A second identical food frequency questionnaire was mailed to both cases and controls on average 2 years after the hip fracture event. In total 98 case/control pairs could be included in the analysis. The association between diet and hip fracture was evaluated and the results from the two dietary assessments were contrasted. Women who themselves claimed that they had not changed their diet in recent years were analysed separately. RESULTS: The hip fracture cases, compared with the controls, had reduced their reported dietary intake of dairy products after the fracture. Apparently this was not intentional since this effect was more pronounced among those cases who claimed that their diet was unchanged. The changes were most apparent among the younger cases with a more recent hip fracture and with a body mass index above the median. Half of the cases, more than twice the frequency in controls, who were initially classified as having high intake of dairy products were classified as having low intake (<800 mg calcium/day) after the hip fracture. This also lowered, in fact reversed, the relative risk estimates of hip fracture both for intake of dairy products and calcium. Crude odds ratios of highest quartile of intake versus lowest, changed from 3.0 to 0.6 for dairy products and from 2.6 to 0.9 for calcium. No other foods or nutrients displayed such notable differences between the two surveys. CONCLUSION: We conclude that the use of current and retrospective dietary information after a hip fracture can lead to a differential misclassification in dietary studies and to biased estimates of hip fracture risk as compared with prospectively collected dietary information.

Age Distribution↗

The Wagner revision stem for severe osteolysis. 31 hips followed for 1.5-5 years.

We used the Wagner (1989) method in 31 hip revisions because of loosening with pronounced scalloping, which made a conventional revision unsuitable. The radiographs showed that within a few months new bone developed in the defects. In 5 cases, a new revision was necessary at an early stage, because of dislocation and/or subsidence. At follow-up after 3 (1.5-5) years, 21 of the remaining 26 hips were pain-free and 23 had almost full range of motion.

Adult↗