Biomedical subjects

O H Sörensen

Publications and source records attributed to O H Sörensen.

7 recordsLinked to original sources

PubMed2004

Seven years of treatment with risedronate in women with postmenopausal osteoporosis.

The effects of 7 years of risedronate treatment were evaluated in a second 2-year extension of a 3-year vertebral fracture study in women with osteoporosis. For the first 5 years of the study, women received risedronate 5 mg/day or placebo according to the original randomization, with maintenance of blinding. All the women who entered into the 6-7 years extension study received risedronate 5 mg/day. Endpoints included vertebral and nonvertebral fracture assessments, changes in biochemical markers of bone turnover, and bone mineral density (BMD) measurements. A total of 164 women (placebo/risedronate group, 81; risedronate group, 83) entered the 6-7 years extension study and 136 (83%) completed the study. Annualized incidence of new vertebral fractures during the 6-7 years was similar between the 2 treatment groups (3.8%). The incidence of vertebral fractures did not change in the 7-year risedronate group during the 6-7 years as compared to 4-5 years, while a significant reduction was observed in the placebo group that switched to risedronate treatment during years 6-7. The incidence of nonvertebral fractures was 7.4% and 6.0% in the placebo/risedronate and risedronate groups, respectively, during years 6-7. Urinary N-telopeptide decreased from baseline by 54% and 63% at 3 months and 7 years, respectively, in the risedronate group. The increases in BMD from baseline after 5 years of risedronate treatment were maintained or increased further during years 6-7; lumbar spine BMD after 5 and 7 years of risedronate treatment increased from baseline by 8.8% and 11.5%, respectively, for this extension study population. Risedronate was well tolerated and the occurrence of upper gastrointestinal adverse events was low. After 7 years of continuous risedronate treatment there were significant increases in BMD and decreases in bone turnover to within premenopausal levels and there was no indication of any loss of anti-fracture efficacy.

Aged↗

PubMed1995

Vitamin D is related to blood pressure and other cardiovascular risk factors in middle-aged men.

A previous study has shown that serum levels of the active vitamin D metabolite 1,25-(OH)2-vitamin D were inversely related to blood pressure levels while the prohormone 25-OH-vitamin D was found to be related to insulin metabolism. Also other clinical and experimental data support the view that vitamin D metabolism is involved in blood pressure regulation and other metabolic processes. The present study was conducted in order to see if the above mentioned relationships between the vitamin D endocrine system and blood pressure, as well as other cardiovascular risk factors, could be found in a cross-section population-based study. Serum levels of 1,25-(OH)2-vitamin D, 25-OH-vitamin D, and blood pressure were therefore measured in 34 middle-aged men and metabolic cardiovascular risk factors were evaluated by means of intravenous glucose and fat tolerance tests, euglycemic hyperinsulinemic clamp, lipoprotein measurements, and lipoprotein lipase activity determinations. Serum levels of 1,25-(OH)2-vitamin D were found to be inversely correlated to the blood pressure (r = -0.42, P < .02), VLDL triglycerides (r = -0.47, P < .005), and to triglyceride removal at the intravenous fat tolerance test (r = 0.34, P < .05), while serum levels of 25-OH-vitamin D were correlated to fasting insulin (r = -0.35, P < .05), insulin sensitivity during clamp (r = 0.54, P < .001), and lipoprotein lipase activity both in adiposal tissue (r = 0.48, P < .005) and skeletal muscle (r = 0.38, P < .03).(ABSTRACT TRUNCATED AT 250 WORDS)

Adipose Tissue↗

PubMed1992

Serum levels of 1,25-(OH)2-vitamin D are not altered by long-term supplementation with alphacalcidol (1-OH-vitamin D3). A double-blind, placebo-controlled study.

The endogenous production of 1,25-(OH)2-vitamin D has been estimated to be 1.5 micrograms daily. Despite the use of alphacalcidol (1,25-(OH)2-vitamin D) during more than a decade the long-term effects of the serum levels of 1,25-(OH)2-vitamin D have been poorly investigated. When 1 microgram of alphacalcidol was given daily to 39 non-vitamin D deficient subjects in a double-blind, placebo-controlled study during 4 months no significant effects on the serum levels of 1,25-(OH)2-vitamin D or 25-(OH)-vitamin D were found. The treatment however induced a 50% increase in urinary excretion of calcium (p less than 0.01). In conclusion, long-term supplementation with a physiological dose of alphacalcidol does not influence the serum levels of 1,25-(OH)2-vitamin D, despite a marked effect on urinary calcium excretion.

Adult↗

PubMed1990

Delayed hypersensitivity in primary and secondary hyperparathyroidism. Treatment with active vitamin D.

The vitamin D endocrine system, besides its traditional role in mineral metabolism, also affects the immune system. A recent study demonstrated that vitamin D supplementation restored a blunted delayed hypersensitivity response (DH) in elderly vitamin D-deficient subjects. In the present study the DH, as measured by the tuberculin test (PPD), was studied in two groups of patients with a disturbed vitamin D system, i.e. primary hyperparathyroidism (HPT) and secondary HPT due to chronic renal failure. A significant reduction in DH was found in the patients with chronic renal failure when compared to control subjects (4.1 +/- 5.3 vs 12 +/- 9.3 mm, p less than 0.05) whereas only a non-significant tendency to a reduced DH was seen in the HPT patients (9.5 +/- 9.2 mm). Treatment with alphacalcidol, a synthetic analogue to the active vitamin D metabolite over 3-6 months did not affect the DH in any of the hyperparathyroid patient groups. Thus it seems likely that other factors than vitamin D were involved in their reduced DH response.

Calcitriol↗

PubMed1989

An association between mineral metabolism and the renin-aldosterone system in human hypertension.

In recent years abnormalities of calcium metabolism have been described in human hypertension. In this study, the relationships between indices of calcium metabolism and the renin-aldosterone system were studied in 39 subjects with untreated essential hypertension. No significant associations were found between the major determinants of calcium metabolism (plasma ionised calcium, parathyroid hormone and 1,25(OH)2-vitamin D) and the renin-aldosterone system. Serum magnesium was, however, positively correlated to plasma renin activity (PRA) (r = 0.38, P less than 0.05) while both 24 h urinary excretion of calcium and cAMP were found to be correlated to both PRA and urinary aldosterone in a positive way (r = 0.39-0.42, P less than 0.01 and r = 0.33-0.57, P less than 0.01, respectively). In this study there was no other evidence of any major influence of the renin-aldosterone status on the calcium balance in human hypertension. The urinary leak of calcium might be determined by the action of the renin-aldosterone system.

Adult↗

PubMed1988

Hypertension in primary hyperparathyroidism--reduction of blood pressure by long-term treatment with vitamin D (alphacalcidol). A double-blind, placebo-controlled study.

Patients with primary hyperparathyroidism (HPT) often have raised blood pressure but a simple cause-and-effect relationship has not been established. In 33 persons with probable primary HPT and mild hypercalcemia detected in a health survey, diastolic blood pressure (DBP) was significantly higher than among age- and sex-matched, normocalcemic, controls (89.4 +/- 9.8 (SD) v 85.2 +/- 8.9 mm Hg; P less than 0.05). Among the hypercalcemic individuals, DBP was, in a multivariate analysis, inversely related to the serum calcium and plasma-ionized calcium concentrations and to the serum levels of parathyroid hormone. A prospective, placebo-controlled, double-blind, study evaluating the effects of active vitamin D, alphacalcidol, (1 microgram daily) was carried out in the hypercalcemic patients over a six-month period. This treatment caused a slight further increase (0.05 mmol/L) of both serum calcium and plasma-ionized calcium concentrations. At the same time there was a significant reduction of DBP with a mean of 6.7 mm Hg compared with placebo (P less than 0.05). The hypotensive action of the vitamin D compound was inversely related to the pretreatment serum levels of 1,25(OH)2D3 and additive to concomitant, unchanged, antihypertensive medications. The negative correlation between serum calcium and blood pressure is similar to that obtained in normocalcemic individuals and suggests that raised blood pressure, at least in the milder forms of primary HPT, is only independently associated with the disease. Active vitamin D, although it raises serum calcium, can lower blood pressure also in hypercalcemic patients as previously demonstrated in normocalcemic individuals.

Blood Pressure↗

PubMed1977

Bone composition and vitamin D after Pólya gastrectomy.

With the aim of evaluating bone phosphorus/hydroxyproline ratio (P/Hypro) as an index of osteomalacia, this bone index and the bone mineral content (BMC) have been investigated together with other indices of calcium metabolism in 27 gastrectomized patients. None of the patients had clinically manifest bone symptoms. The mean values of bone P/Hypro, BMC, plasma calcium and plasma magnesium were subnormal; the mean values of serum parathyroid hormone (iPTH) and plasma alkaline phosphatase were elevated. Mean serum 25-hydroxycholecalciferol (25-OH-D) did not differ from normal. A significant positive correlation was found between bone P/Hypro and serum 25-OH-D, but no significant correlation between bone P/Hypro and BMC. Serum 25-OH-D and bone P/Hypro were significantly lower and serum iPTH was significantly higher in a subgroup of 12 patients with no regular supplementary intake of vitamin D. In conclusion, the gastrectomized patients had blood biochemical evidence of a mild vitamin D insufficiency and the low bone P/Hypro values can be explained by mild osteomalacic changes in bone.

Adult↗