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D M Reid

Publications and source records attributed to D M Reid.

At least 91 records · Page 5Linked to original sources
PubMed1998

A UK Consensus Group on management of glucocorticoid-induced osteoporosis: an update.

In the UK, over 250 000 patients take continuous oral glucocorticoids (GCs), yet no more than 14% receive any therapy to prevent bone loss, a major complication of GC treatment. Bone loss is rapid, particularly in the first year, and fracture risk may double. This review, based wherever possible on clinical evidence, aims to provide easy-to-use guidance with wide applicability. A treatment algorithm is presented for adults receiving GC doses of 7.5 mg day(-1) or more for 6 months or more. General measures, e.g. alternative GCs and routes of administration, and therapeutic interventions, e.g. cyclical etidronate and hormone replacement, are recommended.

Bone Resorption↗
PubMed1998

Is screening for osteoporosis worthwhile?

Osteoporosis is a common condition, which is recognised by the occurrence of fragility fractures and leads to considerable mortality and morbidity with huge financial implications world-wide. Based on predicted demographic changes, the implications of this disease are set to increasingly affect the healthcare budgets of all nations. The determinants of fracture are skeletal factors, such as peak bone mass, the rate of bone loss and extra-skeletal factors, which include trauma and the response to that trauma. Some of these factors are genetically determined, but several have environmental origins, which could, theoretically, be manipulated. There are two potential means whereby osteoporotic fractures might be prevented. Measures could be targeted at the entire population, with the aim of shifting the distribution of bone mass in a beneficial direction, through modifying the behaviour of all individuals. The alternative is a high risk approach, whereby intervention is targeted only at those considered to have the greatest risk of future fracture. Mass bone density screening falls into the second approach. Bone density is a good predictor of future fracture risk, and cost-effectiveness analyses of the high risk approach suggest economic benefits of policies targeting pharmacological treatment to those individuals at highest risk. However, there are important concerns about the levels of compliance achievable with such therapeutic interventions, the balance of risks and benefits for some of these interventions (for example, hormone replacement therapy), and the outcome when treatment is discontinued. On current evidence, it is certainly not appropriate to target hormone replacement therapy for women at the menopause on the basis of a bone density screening programme. However, newer bone-specific agents are being developed which might be administered at later ages, closer to the time when fracture incidence rates rise steeply. Bone densitometry has been shown to predict fractures even in the elderly, and high risk strategies for the targeting of such agents (for example, the bisphosphonates or selective oestrogen receptor modulators) will remain important research issues for the future.

Bone Density↗
PubMed1998

Management of male osteoporosis: report of the UK Consensus Group.

Although osteoporosis is generally regarded as a disease of women, up to 30% of hip fractures and 20% of vertebral fractures occur in men. Risk factors for osteoporotic fractures in men include low body mass index, smoking, high alcohol consumption, corticosteroid therapy, physical inactivity, diseases that predispose to low bone mass, and conditions increasing the risk of falls. The key drugs and diseases that definitely produce a decrease in bone mineral density (BMD) and/or an increase in fracture rate in men are long-term corticosteroid use, hypogonadism, alcoholism and transplantation. Age-related bone loss may be a result of declining renal function, vitamin D deficiency, increased parathyroid hormone levels, low serum testosterone levels, low calcium intake and absorption. Osteoporosis can be diagnosed on the basis of radiological assessments of bone mass, or clinically when it becomes symptomatic. Various biochemical markers have been related to bone loss in healthy and osteoporotic men. Their use as diagnostic tools, however, needs further investigation. A practical approach would be to consider a bone density more than one SD below the age-matched mean value (Z < -1) as an indication for therapy. The treatment options for men with osteoporosis include agents to influence bone resorption or formation and specific therapy for any underlying pathological condition. Testosterone treatment increases BMD in hypogonadal men, and is most effective in those whose epiphyses have not closed completely. Bisphosphonates are the treatment of choice in idiopathic osteoporosis, with sodium fluoride and anabolic steroids to be used as alternatives.

Adult↗
PubMed1998

Comparison of the precision of two vertebral morphometry programs for the lunar EXPERT-XL imaging densitometer.

Comparative precision tests of the vertebral height measurement function of the Aberdeen Vertebral Morphometry System (AVMS) software and Lunar EXPERT-XL software were undertaken using four vertebrae from the same lateral spine dual energy X-ray absorptiometry (DXA) image of the same subject (male, 67 years). Two of the vertebrae were abnormal and two were normal. Three observers inexperienced in morphometry and one experienced observer took part in the study. Repeatability was obtained from 10 sequential measurements of the posterior, middle and anterior heights at the same sitting by the same observer. Intraobserver reproducibility compared the means of one set of measurements for all vertebrae with another taken 1 week later. Interobserver reproducibility compared the means of one set of measurements for all vertebrae from an experienced and an inexperienced observer, and from two inexperienced observers. The AVMS software had significantly higher (p < 0.05) repeatability (mean coefficient of variability, CV = 3.5%) than the Lunar software (mean CV = 5%), significantly higher (p < 0.01) intraobserver reproducibility (mean CV = 4.6%) than the Lunar software (mean CV = 8.5%), and significantly higher (p < 0.05) interobserver reproducibility (mean CV = 4.7%) than the Lunar software (mean CV = 7.5%). In conclusion, the new AVMS method possessed higher precision when measuring both abnormal and normal vertebrae and when used by both experienced and inexperienced observers.

Absorptiometry, Photon↗
PubMed1997

Randomized trial of osteoporosis screening. Use of hormone replacement therapy and quality-of-life results.

BACKGROUND: Screening perimenopausal women for low bone density has yet to be tested in a randomized trial. The effect of screening on the use of hormone replacement therapy (HRT) and the subsequent quality of life in these women is unknown. The purpose of this study was to assess the effect of a screening program on HRT use of quality of life. METHODS: A random sample of women aged 45 to 54 years and living within 32 km of Aberdeen, Scotland, was selected from the community health index. Subjects were further randomized to screening or no screening using the design of Zelen. Two years after randomization, a questionnaire follow-up was mailed to both groups to assess HRT use and quality-of-life scores. RESULTS: Use of HRT was higher in the screened group (30% vs 24%; difference, 6%; 95% confidence interval, 1%-11%; P = .02). A multivariate analysis indicated that the odds of using HRT for a screened woman whose measurement for bone mineral density was in the lowest quartile was 2.54 (95% confidence interval, 1.74-3.71) greater than that of an unscreened woman. Screening and subsequent HRT use did not have any detectable effects-positive or adverse-on women's quality of life. CONCLUSION: Screening for low bone density significantly increases the use of HRT in this population but without any immediate adverse or positive effects on quality of life.

Bone Density↗
PubMed1997

Mothers and daughters menopausal ages: is there a link?

OBJECTIVE: To confirm whether there is a familial association in menopausal age between mothers and daughters. DESIGN: questionnaire survey of women attending an osteoporosis screening programme. SUBJECTS: 551 women who fulfilled the study inclusion criteria out of a random population sample of 2399 women aged between 45 to 54 living within 32 km of Aberdeen who were selected from the community health index. RESULTS: 1758 women attended screening and completed the questionnaire. Of these only 1081 women were eligible being neither hormone replacement therapy users, nor had they had a hysterectomy. However, only 551 (51%) knew their mothers menopausal age. Women with premature (< 40 years) and early menopause (< 45 years) reported significantly lower maternal menopausal ages than women with normal menopausal ages (43.81, 45.40 and 48.38 for premature, early and normal women respectively p < 0.0001). The odds of a woman having an early or premature menopause if their mother had experienced an early menopause was 6.02 (95% confidence interval 3.39 to 10.66). CONCLUSION: There seems to be a strong relationship between mothers and daughters menopausal age.

Adult↗
PubMed1997

Alcohol consumption and age of maternal menopause are associated with menopause onset.

OBJECTIVES: To examine whether a number of nutritional and familial factors were associated with menopausal development. METHODS: A prospective postal survey amongst a random sample of 1227 women aged 47 to 51 who were premenopausal in a cross-sectional survey 2 years previously. Women were classed into three groups; premenopause (regular menstruation); irregular menstruation; postmenopausal (absence of menstrual cycle for at least 6 months). Proportional odds regression was used to identify those factors which were independently predictive of subsequent menopausal development. RESULTS: There was an 80% (n = 983) survey response rate. After exclusion of current HRT users (n = 178); 150 (19%) women were postmenopausal, 277 (34%) had erratic menstruation and 378 (47%) were premenopause. There were significant univariate associations between menopausal status and age (P < 0.001), age of maternal menopause (P = 0.006), alcohol consumption (P = 0.005) and social class (P = 0.03). Maternal age and alcohol consumption were significantly correlated with estradiol levels (r = 0.45, P = 0.02, and r = 0.61, P = 0.02 for maternal age and alcohol consumption, respectively). In proportional odds regression analyses, age, maternal menopausal age, alcohol consumption and smoking were independently associated with menopausal status. CONCLUSIONS: These results suggest that, (1) there is a strong familial association in menopausal age, and (2) moderate consumption of alcohol is associated with delayed menopausal development.

Age Factors↗
PubMed1997

Secondary osteoporosis.

Secondary osteoporosis is diagnosed when there is a well-established disease-related risk factor for fracture or low bone mass. Secondary osteoporosis is associated with a substantial minority of osteoporotic fractures in women perhaps with a majority of osteoporotic related fractures in men. This chapter does not review all the possible causes of low bone mass and fractures but picks out some of the more important causes of, with an emphasis on the main iatrogenic cause, that is corticosteroid induced osteoporosis. It also highlights some of the possible causes which could be avoidable. Where appropriate the methods of prevention and treatment of secondary osteoporosis are reviewed.

Adrenal Cortex Hormones↗
PubMed1997

Polymorphisms of the interleukin-6 gene are associated with bone mineral density.

Genetic factors play an important role in determining bone mass and several genes probably act as regulators of this process. Interleukin-6 (IL-6) is a candidate gene for regulation of bone density, since it has stimulatory effects on cells of the osteoclast lineage and has been implicated in the pathogenesis of bone loss associated with estrogen deficiency. Here we studied the relationship between bone mineral density (BMD) and a polymorphic AT rich minisatellite repeat in the 3' flank of the IL-6 gene in a cohort of 200 women. Six length variants were identified (designated A-F), but four of these were rare such that the last majority of individuals fell into one of two common genotypes: F/F (58.5%) and C/F (27.5%). There was a significant relationship between IL-6 genotype and bone mass at the lumbar spine as determined by analysis of variance (p = 0.04) and a similar trend for bone mass at the femoral neck (p = 0.11). When BMD values were compared in the two common genotypes, we found that spine BMD values were significantly higher in the C/F genotype (mean +/- SEM = 0.94 +/- 0.04 g/cm2) as compared with the F/F genotype (0.81 +/- g/cm2; p = 0.012). A similar trend was seen for hip BMD values, but here, the difference failed to reach statistical significance (p = 0.06). Further analysis showed that genotype-specific effects on bone mass were observed in both premenopausal and postmenopausal women and did not increase with age, suggesting that the association between IL-6 polymorphisms and bone density may be mediated by an effect on peak bone mass, rather than rate of bone loss. We conclude that bone mass is associated with two common polymorphisms of the IL-6 gene. Although the mechanisms that underlie this association will require further research, our data suggest that polymorphic variation at the IL-6 gene locus may contribute to the genetic regulation of bone mass.

Absorptiometry, Photon↗
PubMed1997

Differential and wound-inducible expression of 1-aminocylopropane-1-carboxylate oxidase genes in sunflower seedlings.

In an effort towards understanding the biochemical properties and physiological functions of 1-aminocyclopropane-1-carboxylic acid (ACC) oxidase homologues, we have isolated three ACC oxidase clones from sunflower (Helianthus annuus) seedlings. ACCO1 is a cDNA clone while ACCO2 and ACCO3 and reverse transcriptase-polymerase chain reaction clones. Southern analysis indicated the existence of at least three members in the sunflower ACC oxidase gene family. Expression studies showed that ACCO3 was equally expressed in leaves, hypocotyl, and roots of sunflower seedlings, but it constituted only a small amount of the total ACC oxidase transcripts. In contrast, ACCO1 and ACCO2 were differentially expressed in these organs. ACCO1 mRNA was most abundant in roots, whereas ACCO2 was the major homologue in leaves and in hypocotyl. The levels of total ACC oxidase transcripts in these organs were also determined. High ACC oxidase transcript levels were associated with tissue containing rapidly dividing cells. Wounding and silver ion treatments of hypocotyls increased ACC oxidase mRNA levels and ACC oxidase activity; these events being consistent with the increases in ethylene production. In contrast, ACC oxidase protein levels were not affected by these treatments, suggesting that either a translational regulation and/or a rapid turn-over of the protein is involved in both wound- and silver ion-induced gene expression. Contrary to data in the literature, we found that auxins, ethephon and ACC did not affect ACC oxidase mRNA levels in sunflower hypocotyls. The complexity of ACC oxidase regulation and the significance of organ differential expression of ACC oxidase genes are discussed.

Amino Acid Oxidoreductases↗
PubMed1997

Nutritional influences on bone mineral density: a cross-sectional study in premenopausal women.

The association between current and past dietary intake and bone mineral density (BMD) was investigated in 994 healthy premenopausal women aged 45-49 y. BMD was measured with dual-energy X-ray absorptiometry (DXA). Dietary intake was assessed with a food-frequency questionnaire (FFQ). Energy-adjusted nutrient intakes were grouped into quartiles and mean BMD at the lumbar spine (LS), femoral neck (FN), femoral trochanter (FT), and femoral Wards (FW) were calculated. With higher intakes of zinc, magnesium, potassium, and fiber, LS BMD was significantly higher (P < 0.05-0.006), and a significant difference in LS BMD was also found between the lowest and highest quartiles for these nutrients and vitamin C intake (P < 0.05-0.01). These results remained significant after adjustment for important confounding factors. LS BMD and FT BMD were lower in women reporting a low intake of milk and fruit in early adulthood than in women with a medium or high intake (P < 0.01). High, long-term intake of these nutrients may be important to bone health, possibly because of their beneficial effect on acid-base balance.

Absorptiometry, Photon↗
PubMed1997

Estimating the cost effectiveness of screening tests.

A number of criteria have been postulated that a screening test should fulfill in order for it to be a good or worthwhile screening tool. However, it is a rare test which fulfills all the criteria that have been thought to be important. Therefore, there always exists some form of trade-off between, for example, the detection rate and the false-positive rate and cost. It is the magnitude and form of these trade-offs, which differ for each screening test, that are important, not whether a test fulfills some arbitrary set of criteria. In this paper, we describe some of the trade-offs which occur when appraising a screening test and we argue that listing arbitrary criteria is an unhelpful activity.

Cost-Benefit Analysis↗
PubMed1997

Effects of disease and corticosteroids on appendicular bone mass in postmenopausal women with rheumatoid arthritis: comparison with axial measurements.

The potential value of measurements of peripheral bone mass in rheumatoid arthritis (RA) as an assessment of long-term disease activity has recently received renewed attention. This study examines the effects of RA and corticosteroid therapy on newer methods of measuring peripheral bone mass, comparing the results with dual-energy X-ray absorptiometry (DXA) at axial sites. Peripheral quantitative computed tomography of the radius, ultrasound of the calcaneus, and DXA of the hip and spine were compared between 29 controls and 46 women with RA of whom 25 were receiving low-dose corticosteroid therapy. Bone mass was significantly reduced in the RA groups for: (i) radial trabecular (36.1%) and total (15.6%) measurement sites; (ii) calcaneal ultrasound attenuation (31.7%) and velocity (6.6%); and (iii) femoral neck (15.4%) bone mineral density. Lumbar spine and radial cortical measurements were not significantly affected. There were no significant differences between the RA groups. Disease activity and physical activity did appear to be responsible for much of the reduction in bone mass. These results demonstrate that RA is associated with significant bone loss at the hip, radius and calcaneus, but not at the lumbar spine. In this small study, low-dose corticosteroids had little additional deleterious effect.

Absorptiometry, Photon↗
PubMed1997

gamma-Aminobutyric acid stimulates ethylene biosynthesis in sunflower.

gamma-Aminobutyric acid (GABA), a nonprotein amino acid, is often accumulated in plants following environmental stimuli that can also cause ethylene production. We have investigated the relationship between GABA and ethylene production in excised sunflower (Helianthus annuus L.) tissues. Exogenous GABA causes up to a 14-fold increase in the ethylene production rate after about 12 h. Cotyledons fed with [14C]GABA did not release substantial amounts of radioactive ethylene despite its chemical similarity to 1-aminocyclopropane-1-carboxylic acid (ACC), indicating that GABA is not likely to be an alternative precursor for ethylene. GABA causes increases in ACC synthase mRNA accumulation, ACC levels, ACC oxidase mRNA levels, and in vitro ACC oxidase activity. In the presence of aminoethoxyvinylglycine or alpha-aminoisobutyric acid, GABA did not stimulate ethylene production. We therefore conclude that GABA stimulates ethylene biosynthesis mainly by promoting ACC synthase transcript abundance. Possible roles of GABA as a signal transducer are suggested.

Amino Acid Oxidoreductases↗
PubMed1997

The role of endogenous ethylene in the expansion of Helianthus annuus leaves.

The possible role of ethylene in leaf expansion of the primary leaves of sunflower plants (Helianthus annuus) was studied. Our lowest application of ethephon promoted expansion of primary leaves. Higher concentrations of ethephon, and a range of concentrations of 1-aminocyclopropane-1-carboxylic acid, increased endogenous ethylene concentration and caused a reduction in the area of the primary leaves. The inhibition in leaf expansion induced by ethephon and 1-aminocyclopropane-1-carboxylic acid was reversed by pretreating the plants with an inhibitor of ethylene action, namely silver thiosulphate. Treating leaves with lower concentrations of aminoethoxyvinylglycine reduced ethylene production and stimulated leaf expansion. This effect of aminoethoxyvinylglycine could be nullified by pretreating the plants with 1-aminocyclopropane-1-carboxylic acid. Treatment with silver thiosulphate enhanced leaf expansion. This indicates that endogenous ethylene normally plays a significant role in leaf expansion. Flooded and gravistimulated plants produced more ethylene and had smaller leaves. This could suggest that the increased ethylene is the main cause of the slowed leaf growth, however, only in some cases were we able to partially reverse the effect of flooding with silver thiosulphate. This indicates that there are probably many factors, in addition to increased ethylene, that inhibit leaf expansion in flooded and gravistimulated plants.

Amino Acids↗