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Biomedical subjects

C Christiansen

Publications and source records attributed to C Christiansen.

At least 271 records · Page 15Linked to original sources
PubMed1991

Use of nasally administered salmon calcitonin in preventing bone loss.

This article reviews several of our studies in which we evaluated the effect of nasal salmon calcitonin in preventing bone loss in normal women just after menopause. In the first study, after treatment with nasal salmon calcitonin, bone loss stopped and, in fact, actually increased slightly. In contrast, the placebo group continued to lose bone mass. On the other hand, bone mass in the forearm, which has more cortical bone, showed no change in response to nasal salmon calcitonin. The effect of salmon calcitonin nasal spray in women with established osteoporosis has also been studied. In one study, bone mass in the forearm was constant in the group receiving nasal salmon calcitonin plus calcium, whereas bone mass in the placebo plus calcium group decreased by roughly 2%. Similarly, patients in the group without any treatment also lost 2%. The effect of nasal salmon calcitonin is probably the result of a reduction in the bone resorption to a level seen in premenopausal females. When women were divided according to their baseline bone turnover or initial bone mass, the women with the highest turnover level (assessed by alkaline phosphatase or fasting urinary hydroxyproline) or the lowest bone mass were the group with the greatest increase in bone mass. In conclusion, treatment with salmon calcitonin nasal spray in patients with established osteoporosis stops bone loss, normalizes bone turnover, and causes no subjective or objective side effects.

Administration, Intranasal↗
PubMed1991

The impact of measurement errors on the diagnostic value of bone mass measurements: theoretical considerations.

It has become clear over the last decade that correlations between measurements of forearm bone mineral content (BMCarm) by single-photon absorptiometry (SPA) and measurements of spinal bone mineral density (BMDspine) by dual-photon absorptiometry (DPA) in healthy subjects and patients with spinal fractures are invariably significant, but not very powerful (i.e. r = 0.5-0.7). Nonetheless, several recent studies have shown that appendicular bone mass measurements discriminate between spinal fracture and non-fracture at least as well as do spinal DPA measurements. Correlations of a given parameter with measured BMDspine are less important than those with true BMDspine. To establish the latter we made the following assumptions: (1) accuracy errors or SPA BMCarm and DPA BMDspine measurements of 2%-4% and 8%-10%, respectively; and (2) a measured biological variation of SD = 14% for both BMCarm and BMDspine, corresponding to that of healthy women at the menopause. On these assumptions, we found that a correlation between true BMCarm and true BMDspine at about r = 0.8-0.9 yields a correlation between measured BMCarm and measured BMDspine at about r = 0.6--corresponding to experimental data in healthy women at the menopause. Furthermore, we found that the correlation between DPA measured BMDspine and true BMDspine is about the same as that between the SPA measured BMCarm and the true BMDspine. Thus, with the assumptions given above, spinal (DPA) and fore-arm (SPA) measurements appears to predict equally the true BMDspine in healthy perimenopausal women.

Bone Density↗
PubMed1991

Bleeding patterns during continuous combined estrogen-progestogen therapy.

Bleeding and climacteric symptoms were recorded in two groups of postmenopausal women receiving either continuous combined estradiol and norethisterone acetate or estradiol and cyproterone acetate. Out of a sample of 99 postmenopausal women aged 45 to 54 years, 86 completed a 2-year, double-blind, placebo-controlled study. Comparison of the bleeding patterns in the two groups revealed a statistically significant difference: More women in the estradiol-cyproterone acetate group experienced bleeding and for a longer duration. Thirteen women in the estradiol-norethisterone acetate group were amenorrheic, compared with two in the other group. The Kupperman index score in both groups declined to about 30% to 40% of initial values (p less than 0.001). The hot flushes in both treatment groups decreased to a highly significant degree (p less than 0.001), to a value below 20% of baseline values. We conclude that a continuous combination of estrogen and progestogen can produce amenorrhea and symptomatic relief. However, the progestogen components seem to differ in their ability to control bleeding.

Amenorrhea↗
PubMed1991

Postmenopausal hormone replacement therapy prevents central distribution of body fat after menopause.

The reduction in cardiovascular risk induced by hormone replacement therapy is only partly explained by changes in serum lipids and lipoproteins. As body composition and body fat distribution in particular are independent predictors of cardiovascular disease, we investigated the effect of postmenopausal hormone therapy on body composition parameters directly measured. Sixty-two early postmenopausal women were followed up for 2 years in a prospective, randomized, placebo-controlled study. We found that combined estrogen-progestogen therapy prevented the increase in abdominal fat after menopause (P less than .05), and that this effect was independent of the effect on serum lipids and lipoproteins. The therapy reduced postmenopausal bone loss significantly (P less than .001), whereas it did not have a statistically significant influence on total body fat mass or total lean body mass. The findings of the present study suggest that some of the protective impact of postmenopausal hormone therapy on cardiovascular disease may be explained by the effect on body composition, in particular abdominal fat.

Abdomen↗
PubMed1991

The carboxy-terminal propeptide of type I procollagen in serum as a marker of bone formation: the effect of nandrolone decanoate and female sex hormones.

Seventy-nine osteoporotic (prior forearm or vertebral fracture), but otherwise healthy, postmenopausal women (aged 55 to 75 years) were allocated to two double-blind trials: (1) 39 women received either nandrolone decanoate (anabolic steroid) 50 mg as an intramuscular depot injection or a placebo injection every 3 weeks for 1 year; and (2) 40 women received either 2 mg 17 beta-estradiol plus 1 mg norethisterone acetate or placebo tablets daily for 1 year. Sixty-seven (85%) completed the 1 year of treatment. Serum concentration of type I procollagen carboxy-terminal propeptide (PICP) was measured before and at 3, 6, 9, and 12 months of therapy. In addition, 32 of the women had an iliac bone biopsy taken after double tetracycline labeling. Initial serum PICP correlated significantly with histomorphometrically measured rate of bone formation (r = .4; P less than .05) and plasma bone Gla protein (r = .6; P less than .001), but not with histomorphometrically measured bone resorption or biochemical estimates of bone resorption (fasting urinary hydroxyproline and calcium). Estrogen-progestogen therapy significantly decreased (P less than .001) serum PICP by about 30%, whereas anabolic steroid therapy hardly affected it. We conclude that serum PICP may be used as a noninvasive measurement of bone formation on a group basis. Whereas bone formation is clearly decreased during estrogen-progestogen therapy, it is not affected by long-term therapy with anabolic steroids.

Aged↗
PubMed1991

Progestogens: therapeutic and adverse effects in early post-menopausal women.

Progestogen treatment is associated with a number of subjective symptoms. In the present study, 148 healthy post-menopausal women suffering from mild climacteric symptoms were randomly allocated to 12 weeks of treatment with (a) 2 mg oestradiol valerate combined with cyproterone acetate, medroxyprogesterone acetate or levonorgestrel; (b) 1.5 mg 17 beta-oestradiol combined with desogestrel; or (c) placebo. Climacteric symptoms, Kupperman index scores and potential adverse progestogen effects were recorded before treatment and three times per month during therapy. All the hormone regimens had a rapid effect, reducing the severity of climacteric symptoms to about 30% of the baseline values (P less than 0.001) within one month. Hot flushes were reduced in severity and/or frequency by 76 100% within 3 months (P less than 0.001). The regimens which included hydroxyprogesterone derivatives produced a transient increase in breast tenderness. Other recorded potential adverse progestogen effects showed no significant changes during the study. We concluded that the addition of progestogens (whether 19-nortestosterone or hydroxyprogesterone derivatives) does not produce significant side effects during combined hormone replacement therapy.

Androgen Antagonists↗
PubMed1991

Serum-free gamma carboxyglutamic acid (free Gla) is a poor biochemical marker of bone resorption in early postmenopausal women.

In this study, we assessed the potential value of serum-free Gla to reflect changes of bone turnover at menopause. Serum-free Gla was measured in 49 healthy postmenopausal women and 19 healthy age-matched premenopausal women. No difference in serum-free Gla concentrations was observed between the two groups. In a double-blind longitudinal study of 36 postmenopausal women (a subgroup of the above 49 women) treated with either oral oestradiol valerate in a cyclical combination with cyproterone acetate (n = 19) or placebo (n = 17) for nine months, the serum-free Gla concentration was unchanged with placebo and decreased by only 10% after hormonal replacement therapy. Initial serum-free Gla concentrations in postmenopausal women did not correlate with other biochemical markers of bone turnover. The predictive value of serum-free Gla concentration for the spontaneous rate of bone loss in early postmenopause was also assessed, and the marker showed no correlation to bone loss. These data indicate that the serum concentration of free Gla is not a useful marker of the bone turnover rate in the early postmenopause.

Biomarkers↗
PubMed1991

Measurement of body fat in elderly subjects by dual-energy x-ray absorptiometry, bioelectrical impedance, and anthropometry.

Body fat was measured in 46 elderly subjects by dual-energy x-ray absorptiometry [BF(DEXA)], bioelectrical impedance analysis (BIA), and anthropometry. Equations for prediction of the body fat (by DEXA) of elderly people by BIA and/or anthropometry were developed. The prediction of body fat (by DEXA) by anthropometric variables alone gave an r2 of 0.94 and the corresponding SEEs were 1.61 kg for men and 2.43 kg for women. When BIA variables were added as predictors, r2 increased by 2-5% (P less than 0.05) and the corresponding SEE decreased by 25% (P less than 0.05). The prediction of body fat (by DEXA) in elderly subjects and by BIA or anthropometry with equations developed in populations of young healthy adults (adapted from the literature) was generally not good although the correlation coefficients were high (r greater than 0.9, P less than 0.001), which suggests that our equations may improve prediction of body fat in elderly subjects.

Absorptiometry, Photon↗
PubMed1991

Radiology and imaging determinants of bone mass.

Osteoporosis is a disease that shows no symptoms until fractures occur, and for that reason, relatively few diagnoses are made in time for effective therapy to be administered. Consequently, a large number of individuals experience the pain, expense, disability, and decreased quality of life caused by these age-related fractures. Sufficient diagnosis should result in decreased morbidity from osteoporotic fractures, and for that purpose determinations of bone mass and rate of bone loss are important. This review briefly outlines the most recent developments in this area with special attention to the issues on which those in the field today are in general agreement.

Absorptiometry, Photon↗
PubMed1991

Influence of temperature of bupivacaine on spread of spinal analgesia.

A prospective, randomised study was performed to investigate the influence of temperature on sensory blockade in spinal anaesthesia. Three ml of plain bupivacaine 0.5% were injected intrathecally at either 4 degrees C, room temperature, or 37 degrees C. There were 10 patients in each group, who were kept sitting for 2 minutes after injection. The maximum level of sensory blockade was significantly higher (p less than 0.01) in the group who received the solution adjusted to 37 degrees C, and variability of level was smaller (p less than 0.05). Time to two-segment regression was shorter in the 37 degrees C group than in the 4 degrees C group (p less than 0.05). Hypotension required administration of ephedrine more often in the 37 degrees C group (p less than 0.05). It is concluded that the use of plain bupivacaine 0.5% adjusted to 37 degrees C results in a higher and more predictable sensory blockade.

Aged↗
PubMed1991

The effect of growth hormone (GH) therapy on urinary pyridinoline cross-links in GH-deficient adults.

OBJECTIVE: The aim was to study the effect of growth hormone (GH) on new markers of bone resorption (fasting urinary excretion of pyridinium cross-links (pyridinoline and deoxypyridinoline)) in GH-deficient adults. DESIGN: Randomized, double-blind, placebo-controlled cross-over study. The treatment periods (GH 2 IU/m2 subcutaneously, or placebo daily for 4 months) were separated by a 4-month washout period. PATIENTS: Twenty GH-deficient adults (aged 18-39). MEASUREMENTS: Blood and fasting urine samples were collected at the end of each 4-month treatment period. Plasma bone Gla protein was measured by radioimmunoassay and urine pyridinoline and deoxypyridinoline were measured by spectrofluorometry after high performance liquid chromatography and corrected for urinary creatinine. RESULTS: GH increased fasting urinary excretion of pyridinoline (287 +/- 123%, P less than 0.001) and deoxypyridinoline (313 +/- 140%, P less than 0.001). The GH-induced increment in these parameters correlated with the increase seen in plasma bone Gla protein (r = 0.83-0.86, P less than 0.001). CONCLUSION: Four months of GH substitution in GH-deficient adults increases bone resorption as well as bone formation. The effect on bone mass has yet to be assessed.

Adolescent↗
PubMed1991

Desogestrel in hormone replacement therapy: long-term effects on bone, calcium and lipid metabolism, climacteric symptoms, and bleeding.

Seventy-three healthy, postmenopausal women, aged 45-54 years, were randomly assigned to one of three groups for 2 years of treatment: 17 beta-oestradiol 1.5 mg on days 1-12 and 17 beta-oestradiol 1.5 mg + desogestrel 150 micrograms on days 13-24 (E2/DG) or oestradiol valerate 2 mg on days 1-11 and oestradiol valerate 2 mg + medroxyprogesterone acetate 10 mg on days 12-21 (E2V/MPA) or placebo. Fifty-seven women (78%) completed the study. Bone mineral content of the distal regions of the forearms (measured by single photon absorptiometry, SPA) and bone mineral density of the spine (measured by dual energy X-ray absorptiometry, DXA) showed increases of 0.5-1% and 4-5%, respectively, in the hormone groups over 2 years. The placebo group exhibited a decrease in spinal bone density of 2% per year, and in the forearm of 2.5-3.5% per year. Biochemical estimates of bone turnover (serum alkaline phosphatase and fasting urinary calcium) decreased significantly to premenopausal levels in the hormone groups but remained unchanged in the placebo group. In both hormone groups total cholesterol decreased by about 9% (P less than 0.001), whereas low density lipoprotein cholesterol decreased by 16% in the E2/DG group and 20% in the E2V/MPA group (P less than 0.001). High density lipoprotein cholesterol showed only minor, insignificant changes in the hormone groups. The placebo group had virtually unchanged values. Climacteric symptoms, including hot flushes, were significantly reduced in both hormone groups. Bleeding occurred regularly in about 80% of the women.(ABSTRACT TRUNCATED AT 250 WORDS)

Absorptiometry, Photon↗
PubMed1991

Validation of body composition by dual energy X-ray absorptiometry (DEXA).

The present study validates the use of dual energy X-ray absorptiometry (DEXA) for measurement of body composition. The precision error was expressed as the SD (CV%) for fat mass, FAT%, lean tissue mass, and total body bone mineral: 1.1 kg (6.4%), 1.6% (5.7%), 1.4 kg (3.1%), and 0.03 kg (1.2%), respectively. The accuracy study in vitro used (1) mixtures of water and alcohol, (2) mixtures of ox muscle and lard, and (3) dried bones. In the clinically relevant range of values there were only small influences on DEXA measurements of variations in amount and composition of the soft tissue equivalents. The accuracy study in vivo compared the components of body composition measured recently by DEXA and earlier by dual photon absorptiometry, counting of naturally occurring total body 40K, and body density by underwater weighing in 25 healthy adult subjects. We found agreement between fat percentage (and lean body mass) by DEXA and the three established measurements modalities; mean differences were (-5.3 to -0.4%) and (-0.7 to 2.5 kg) for fat percentage and lean body mass, respectively. We conclude that DEXA provides a new method of measuring body composition with precision and accuracy errors, which are compatible with the application of DEXA in group research studies and probably also in clinical measurements of the single subject.

Absorptiometry, Photon↗
PubMed1991

Hormone replacement therapy prevents coronary artery disease in ovariectomized cholesterol-fed rabbits.

The prevention of coronary artery disease in women is of considerable importance. We have therefore investigated the influence of oestrogen monotherapy and oestrogen-progestogen replacement therapy on coronary artery disease using a simple morphometric method. We studied sixty-three cholesterol-fed rabbits for nineteen weeks. They were randomized to either ovariectomy (51 rabbits) or a sham operation (12 rabbits). The ovariectomized rabbits were randomized to receive either 17 beta-estradiol, 17 beta-estradiol plus norethisterone acetate, 17 beta-estradiol plus levonorgestrel, or placebo. The rabbits with the sham operation received placebo. The hormone therapies reduced the development of coronary artery disease compared to placebo (p less than 0.0001). Furthermore, the coronary artery disease was attended by atherosclerosis in the more distal parts of the coronary arteries (p less than 0.0001), the thoracic aorta (p less than 0.0001) and the abdominal aorta (p less than 0.0001), and by a reduced relative heart weight (p less than 0.05). We conclude that coronary atherosclerosis can be determined quantitatively by morphometry in rabbit arteries. Estradiol monotherapy reduces coronary atherosclerosis in cholesterol-fed rabbits and the addition of norethisterone acetate or levonorgestrel does not attenuate this beneficial effect.

Animals↗
PubMed1991

Body composition and calcium metabolism in adult treated coeliac disease.

Twenty two treated adult patients with coeliac disease (aged 20-70 years) were examined. Body composition was assessed from anthropometry and directly measured by dual photon absorptiometry. Bone mineral content was measured in the spine (dual photon absorptiometry) and at two forearm sites (single photon absorptiometry). Compared with age matched healthy subjects, treated coeliac patients had lower body mass index (-5%, p less than 0.05) and lower directly measured total body fat mass (-30%, p less than 0.001). They also had decreased bone mineral content (-9 to -13%, p less than 0.01) in the spine and in the forearms. The serum concentrations of albumin, D vitamin binding protein, and iron were reduced (-6 to -22%, p less than 0.01), but otherwise blood and urine analyses were normal. We conclude that this group of treated adult coeliac patients had a reduced fat mass and bone mineral content compared with the general population.

Adult↗
PubMed1991

Estrogen monotherapy and combined estrogen-progestogen replacement therapy attenuate aortic accumulation of cholesterol in ovariectomized cholesterol-fed rabbits.

Cardiovascular disease is currently the leading cause of death among women in the United States. To investigate the effect of postmenopausal hormone therapy on atherogenesis, we studied 75 cholesterol-fed female rabbits for 19 wk. The rabbits were randomly assigned to five groups. Four groups underwent bilateral ovariectomy followed by treatment with either 17 beta-estradiol, 17 beta-estradiol plus norethisterone acetate, 17 beta-estradiol plus levonorgestrel, or placebo. The fifth group had a sham operation and received placebo. The hormone groups had only one-third of the aortic accumulation of cholesterol found in the placebo groups, a difference that was highly statistically significant (P less than 0.0001). No significant differences in aortic accumulation of cholesterol were found in the hormone groups. This indicates that estrogen attenuates atherogenesis in cholesterol-fed ovariectomized rabbits and that two commonly prescribed progestogens do not counteract the effect. The beneficial effect of estradiol could only partly be explained by its lowering effects on serum total cholesterol or VLDL cholesterol, which implies that estradiol possesses additional beneficial effects, possibly a direct action on the arterial wall.

Animals↗