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J A Falch

Publications and source records attributed to J A Falch.

16 recordsLinked to original sources
PubMed1992

Development and evaluation of an index to predict early postmenopausal bone loss.

An index to predict individual postmenopausal bone loss is presented. The index is developed by means of data from a 10-year prospective Norwegian study in which bone mass of the distal forearm was measured annually in 73 women. All the women were 47 years old and premenopausal at inclusion. Independent risk factors for postmenopausal bone loss were identified by applying multivariate regression analysis on anthropometric, biochemical, nutritional, and life-style variables measured at menopause. The analysis identified low body weight, reduced renal phosphate reabsorption, and smoking as significant independent risk factors, and by means of these three factors a predictive index for postmenopausal bone loss was developed. This index was validated by using data from a 10-year longitudinal Dutch study, in which bone mass of the proximal radius was measured annually in 86 women, aged between 49 and 57 years and perimenopausal at inclusion. We defined women with the highest index score as "high-risk persons." According to this definition approximately 25% of the perimenopausal women were classified as high-risk persons, and the estimated sensitivity/specificity/positive predictive power were 36%, 89%, and 74%, respectively, when used to select women with a postmenopausal bone loss above average. We conclude that the index may be helpful in identifying healthy perimenopausal women in whom bone mass measurements should be considered.

Female↗
PubMed1992

Serum levels of intact parathyroid hormone in elderly patients with hip fracture living at home.

The serum levels of intact parathyroid hormone and cholecalciferol metabolites have been measured in patients with hip fracture above 70 years of age admitted to hospital from home-living conditions and compared with serum levels in age- and sex-matched home-living control subjects. It was found that patients with hip fracture had significantly lower levels of calcidiol (29.7 +/- 15.9 vs 46.0 +/- 27.8 nmol/l) and calcitriol (63.6 +/- 25.0 vs 91.1 +/- 39.5 pmol/l) with no difference in serum levels of intact parathyroid hormone (4.7 +/- 2.1 vs 5.3 +/- 3.3 pmol/l). The data suggest that secondary hyperparathyroidism is not an important risk factor in our population of patients with hip fracture.

Aged↗
PubMed1991

[Determination of intact parathyroid hormone in patients with calcium metabolism disorders].

We have used an immunoradiometric assay (IRMA) to measure intact PTH. The serum-levels of PTH followed a log-normal distribution in a population of 85 healthy post-menopausal women, with a geometric mean of 1.9 pmol/l and a range of 0.8-6.1 pmol/l. The correlation between measurements performed using the IRMA and a radioimmunoassay which measured the C-terminal portion of the PTH molecule was 0.85. It was only the IRMA, however, that could measure subnormal values. Two of 27 patients with primary hyperparathyroidism had PTH-values in the upper reference interval. The rest of the patients had elevated levels. Patients with hypercalcemia due to malignancy had subnormal or low normal (less than 2.5 pmol/l) PTH values. Half of the patients with hypoparathyroidism had PTH below the limit of detection. Four subjects with familial hypercalciuric hypercalcemia had normal (3) or slightly elevated PTH-levels.

Adult↗
PubMed1990

Perimenopausal appendicular bone loss: a 10-year prospective study.

The rate of bone loss before and after the menopause were studied prospectively in 73 healthy women, who were all aged 47 and premenopausal at the start of the study. Bone mass was measured annually by radiogrammetry of 6 metacarpals and by dual photon absorptiometry of the distal and proximal forearm. The rate of bone loss was nearly linear the first 6 years both before and after the menopause. At the menopause, the mean rate increased more than 3-fold. The postmenopausal rate of bone loss in the forearm demonstrated an inter-individual normal distribution with a range from 1% to 6% per year. This prospective study suggests that the menopause, and not age per se determines the start of a period with increased rate of bone loss from the appendicular skeleton. As this rate varies considerably between women, estimation of early postmenopausal rate of bone loss will be of importance when advising women concerning prophylactic treatment against osteoporosis.

Absorptiometry, Photon↗
PubMed1988

Validation of a radioreceptor assay for 1,25-dihydroxyvitamin D using selected ion monitoring GC-MS.

This report describes two methods for the measurement of 1,25-dihydroxyvitamin D [1,25(OH)2D] in serum: A modified radio receptor assay (RRA), employing a 1,25(OH)2D receptor from calf thymus, and selected ion monitoring (SIM) with combined capillary gas chromatography (GC)-mass spectrometry (MS). The intra-assay coefficient of variation was close to 13% for both methods, and the inter-assay coefficients of variation were 14.0 and 6.5% for RRA and SIM (GC-MS), respectively. Aliquots of 2 ml (RRA) and 20 ml (SIM) serum were used, and the limits of detection were 10 and 6 pmol/l, respectively. The analytical recovery of each method was assessed, and a maximum deviation from the expected value of 10 and 2% was found for RRA and SIM, respectively. A correlation coefficient of 0.93 (slope 0.97) was obtained when 27 different serum samples were analyzed by both methods. Included in this study were serum samples from healthy subjects and patients with subnormal as well as supranormal 1,25(OH)2D levels. This result showed that the RRA accurately measured the serum levels of 1,25(OH)2D and therefore should be useful in the diagnosis and control of vitamin D dependent diseases.

Adult↗
PubMed1988

A longitudinal study of pre- and postmenopausal changes in calcium metabolism.

Longitudinal changes in the serum concentration of calcium, phosphate, alkaline phosphatase, PTH, calcitonin and the renal handling of calcium and phosphate were studied in 19 normal women of the same age before and after the menopause. Significant increase in serum calcium, phosphate and calcitonin and urine calcium/creatinine and TmPO4/GF were shown to precede the premenopause. After cessation of the menstruation, no statistically significant further changes were observed in these variables. Changes in PTH were not observed neither during the premenopausal nor the post-menopausal period. Alkaline phosphatase increased in the postmenopausal period suggesting an increase in bone turn-over.

Calcium↗
PubMed1987

Postmenopausal osteoporosis: no effect of three years treatment with 1,25-dihydroxycholecalciferol.

The therapeutic effect of 1,25-dihydroxycholecalciferol (1,25(OH)2D3) in postmenopausal osteoporosis was tested in a single blind, randomized prospective study. Thirty-nine women, 50-65 years of age, were treated for three years with 0.5 microgram 1,25(OH)2D3 daily. In a control group, 37 women were given 400 IU vitamin D3 daily. There was no significant difference in annual bone loss from the distal or proximal forearm between the groups. New vertebral fractures were evaluated, and in the treatment group, the annual increase in vertebral fractures was 0.18 +/- 0.387 and in the control group 0.13 +/- 0.330. New long bone fractures were 7 and 5, respectively. None of the observed differences were statistically significant. In the 1,25(OH)2D3 group, 28% had to reduce the dose because of slight hypercalcaemia. We conclude that 1,25(OH)2D3 as used in this study is not effective in the treatment of osteoporosis.

Aged↗
PubMed1987

Early postmenopausal bone loss is not associated with a decrease in circulating levels of 25-hydroxyvitamin D, 1,25-dihydroxyvitamin D, or vitamin D-binding protein.

To study changes in the rate of bone loss before and after the menopause, 19 normal premenopausal women of the same age were followed with annual measurements of appendicular bone mass for 8 yr. Their serum estrone, estradiol, 25-hydroxyvitamin D, 1,25-dihydroxyvitamin D, and vitamin D-binding protein levels also were measured annually. The serum estrogen levels declined before the menopause, and the rate of bone loss more than doubled at the time of the menopause. There were no significant changes in the serum 25-hydroxyvitamin D, 1,25-dihydroxyvitamin LD or vitamin D-binding protein levels from the pre- to the postmenopausal period. We conclude that changes in vitamin D metabolite levels are not associated with early postmenopausal bone loss.

Bone Diseases, Metabolic↗
PubMed1985

Mineral-metabolic side effects of low-dose antacids.

Mineral-metabolic side effects of a low dose of a conventional Al-Mg antacid were examined in 10 healthy volunteers, who were given one antacid tablet after the 3 main meals and at bedtime (buffering capacity, 120 mmol/day) for 4 weeks. Compared with the pre-medication state, the following changes of statistical significance occurred during antacid ingestion: increase in urinary excretion of magnesium, calcium, and aluminum; decrease in urinary excretion of phosphate; increase in maximal renal phosphate reabsorption (Tm PO4/GFR); and increase in serum concentration of aluminum. Most of the changes were normalized 3-4 days after cessation of antacid medication. There was no change in intestinal absorption of calcium. The fact that even this low dose of antacids can provoke measurable changes in mineral metabolism, including aluminum absorption, is noteworthy, although we did not see any clinical symptoms from the biochemical changes.

Adult↗
PubMed1985

Epidemiology of hip fractures in Norway.

During the 2-year period 1978-1979, a total of 2109 hip fractures (of the proximal end of the femur) occurred in Oslo. The age- and sex-specific annual incidence was the highest ever reported. A previous hip fracture had occurred in 13 per cent of the women and 6.8 per cent of the men. In 1979, a total of 5920 hip fractures was reported in Norway. Compared with Oslo, all other counties had a lower incidence. The number of fractures in Oslo was five times greater in 1982 compared with 1950. This increase cannot be explained only by the increasing number of elderly persons.

Adult↗