Search PubMed⌕ Search

Biomedical subjects

B Ettinger

Publications and source records attributed to B Ettinger.

At least 91 records · Page 5Linked to original sources

A practical guide to preventing osteoporosis.

Physicians should advise women reaching menopause about the risk of osteoporosis and what practical steps can be taken to reduce this risk. The average woman at menopause can expect to live to be 80 years old; during these years she will face a 15% risk of hip fracture and a 10% risk of vertebral fracture. These risks are increased in Asians and whites, in women who are short and thin, and in those with poorly developed musculature. General advice regarding the correction of certain unhealthy habits and changes in life-style may enhance skeletal health, but prompt restoration and long-term maintenance of physiologic levels of estrogen remain the only proved effective way of reducing bone loss and the risk of fracture.

Adult↗

Prevention of osteoporosis: treatment of estradiol deficiency.

Estradiol (E2) plays a major role in maintaining women's skeletal integrity. Loss of bone mass is a regular occurrence with E2 deficiency, regardless of etiology. Estrogen-dependent bone loss follows a predictable pattern. Initially, it is quite rapid, preferentially affecting trabecular bone, which may decrease by 5-8% annually, whereas compact or cortical bone decreases by 1-3% annually. After 10-15 years of E2 deficiency, the rate of loss each year decreases; however, by that time, skeletal mass may be one-third to one-half of its youthful level. Because of the resultant skeletal fragility, even minimal trauma can produce fractures of the spine and wrist. After an additional 10-15 years of bone loss, hip fractures occur with alarming frequency. Timely restoration of E2 levels can prevent estrogen-dependent bone loss and can reduce significantly the risk of fracture. Studies show that 2 mg of E2 administered orally is an adequate dose; 1 mg will suffice if it is combined with a high dietary calcium intake. High calcium intake without estrogen is not effective in preventing the accelerated loss of bone that occurs in the years immediately after menopause. Long-term studies confirm that postmenopausal women who regularly use estrogen have greater bone mass and fewer osteoporotic fractures. Physicians should be encouraged to treat all estrogen-deficient women, particularly those who appear to be at higher risk for osteoporosis.

Bone and Bones↗

Optimal use of postmenopausal hormone replacement.

The well-informed physician can use the following specific strategies to help postmenopausal women obtain maximum benefit from estrogen therapy: 1) choosing the woman most likely to benefit; 2) initiating therapy at a time when it will do the most good; 3) tailoring treatment to maximize safety, efficacy, and acceptability; and 4) fostering patient commitment to long-term treatment through education, monitoring, and supportive counseling.

Drug Administration Schedule↗

Overview of the efficacy of hormonal replacement therapy.

The most widely recognized reason for prescribing estrogen for menopausal women is for control of symptoms. Estrogen effectively reduces the vasomotor, somatic, and associated psychologic components of the menopausal syndrome. Recently, however, the role of estrogen in the prevention of disease, particularly osteoporosis, urogenital atrophy, and atherosclerotic cardiovascular disease, has prompted consideration of this treatment for a more long-term goat. Bone loss occurring after menopause can be prevented by the use of estrogen; this significantly reduces the morbidity and mortality of associated fractures. Atrophic changes, which can occur earlier in the menopause than previously recognized, also respond to estrogen treatment. Atherosclerotic risk profiles are improved by estrogen replacement: blood pressure is lowered, total cholesterol and low-density lipoprotein cholesterol are reduced, and high-density lipoprotein cholesterol is increased. Most studies have found that the incidence of angina or myocardial infarction is lower in estrogen users than in nonusers, and overall mortality rates from cardiovascular disease appear to be reduced as well.

Arteriosclerosis↗

Postmenopausal bone loss is prevented by treatment with low-dosage estrogen with calcium.

Bone mass was measured prospectively in 73 women during the period immediately after menopause. By comparing the rates of loss at three skeletal sites, we assessed the protective effects of calcium supplements given alone or combined with low-dosage estrogen therapy. After 2 years of follow-up, spinal trabecular mineral content, measured by quantitative computed tomography, decreased by a mean of 9.0% (p = 0.002 compared with baseline) in untreated women and a mean of 10.5% (p = 0.0001) in women given calcium supplements alone. By contrast, women given conjugated estrogens, 0.3 mg/d, with calcium supplements showed an insignificant increase of 2.3%. Significant losses of a lesser magnitude were seen in the appendicular cortical skeleton of women not receiving therapy and in those receiving calcium alone, but no significant changes were observed in women receiving estrogen with calcium.

Bone and Bones↗

Randomized trial of allopurinol in the prevention of calcium oxalate calculi.

In a double-blind study, we examined the efficacy of allopurinol in the prevention of recurrent calcium oxalate calculi of the kidney. Sixty patients with hyperuricosuria and normocalciuria who had a history of calculi were randomly assigned to receive either allopurinol (100 mg three times daily) or a placebo. After the study, the placebo group had 63.4 percent fewer calculi (P less than 0.001), whereas the allopurinol group had 81.2 percent fewer calculi (P less than 0.001). During the study period, the mean rate of calculous events was 0.26 per patient per year in the placebo group and 0.12 in the allopurinol group. When the treatment groups were compared by actuarial analysis, the allopurinol group was found to have a significantly longer time before recurrence of calculi (P less than 0.02). We conclude that allopurinol is effective in the prevention of calcium oxalate stones in patients with hyperuricosuria. The large reduction in the frequency of calculi in the placebo group underscores the positive treatment bias that regularly occurs in trials of prophylaxis against renal calculi when historical controls are used.

Allopurinol↗

Metabolic fate and solubility of triamterene--not an explanation for triamterene nephrolithiasis.

In an attempt to explain the triamterene stone diathesis, we studied the excretion and solubility of triamterene, 1, and its metabolite, the sulfate ester of the hydroxy derivative of triamterene, 3. The urinary excretion pattern and metabolism in stone formers was the same as in other chronic users of triamterene or healthy volunteers. The solubility of triamterene in urine was approximately one-half of its solubility in buffer solution, whereas the sulfate ester, 3, was nearly twice as soluble in urine as in the buffer solution. In the majority of the subjects studied, we found concentrations of 3 which approached or exceeded apparent solubility limits in urine. This was not true for triamterene where most measured urine concentrations were less than the apparent solubility as determined by equilibration. Alteration in the metabolism of triamterene is probably not a causative factor for triamterene nephrolithiasis. The saturation of urine with triamterene and especially with the sulfate ester, 3, may be related to stone formation, but other physical factors play a role in determining the relative amounts of drug found in calculus material.

Adult↗

Bone mineral changes in primary hyperparathyroidism.

We studied 34 patients with primary hyperparathyroidism in order to assess their bone mineral status, to determine its relationship to biochemical parameters (serum calcium and parathyroid hormone) and surgical status, and to determine the relationship between peripheral cortical bone and spinal trabecular bone in this disease. These patients were studied with radiogrammetry of the metacarpals, Norland-Cameron photon absorptiometry of the radius, quantitative computed tomography (QCT) of the spine, industrial radiography of the hands, and conventional radiography of the thoracolumbar spine. We also calculated a spinal fracture index from thoracolumbar spine films. We found that the appendicular measurements correlated well together, but less well with spinal QCT. The spinal fracture index correlated best with QCT (r = -0.55), although significant dispersion was noted. We found that, in general, these hyperparathyroid patients had statistically significant decrements in bone mineral content in both the appendicular and the axial portions of the skeleton. However, the decrement in the appendicular skeleton did not correlate well with that in the axial skeleton. Therefore we conclude that it is necessary to measure both peripheral and central bone mineral content in order to reliably assess the skeletal demineralizing effects of primary hyperparathyroidism in an individual patient.

Adult↗

Isolated systolic hypertension in the elderly. A placebo-controlled, dose-response evaluation of chlorthalidone.

One hundred seventy-one patients, 60 years of age or older with isolated systolic hypertension, were randomly assigned to receive chlorthalidone 12.5, 25.0, or 50.0 mg or placebo once daily for 12 weeks. The majority of the patients receiving chlorthalidone 12.5 mg achieved therapeutic success with no clinically significant biochemical changes or side effects. The 50.0-mg dose level enhanced efficacy only minimally over the 25.0-mg dose level. Drug-related side effects were significantly more prevalent in the chlorthalidone 50.0-mg group than in the placebo group. The data suggest that most elderly patients with isolated systolic hypertension, regardless of the severity, could be treated effectively and safely with chlorthalidone 12.5 mg per day.

Age Factors↗

Bone mineral content in early-postmenopausal and postmenopausal osteoporotic women: comparison of measurement methods.

To investigate associations among methods for noninvasive measurement of skeletal bone mass, we studied 40 healthy early postmenopausal women and 68 older postmenopausal women with osteoporosis. Methods included single- and dual-energy quantitative computed tomography (QCT) and dual-photon absorptiometry (DPA) of the lumbar spine, single-photon absorptiometry (SPA) of the distal third of the radius, and combined cortical thickness (CCT) of the second metacarpal shaft. Lateral thoracolumbar radiography was performed, and a spinal fracture index was calculated. There was good correlation between QCT and DPA methods in early postmenopausal women and modest correlation in postmenopausal osteoporotic women. Correlations between spinal measurements (QCT or DPA) and appendicular cortical measurements (SPA or CCT) were modest in healthy women and poor in osteoporotic women. Measurements resulting from one method are not predictive of those by another method for the individual patient. The strongest correlation with severity of vertebral fracture is provided by QCT; the weakest, by SPA. There was a high correlation between single- and dual-energy QCT results, indicating that errors due to vertebral fat are not substantial in these postmenopausal women. Single-energy QCT may be adequate and perhaps preferable for assessing postmenopausal women. The measurement of spinal trabecular bone density by QCT discriminates between osteoporotic women and younger healthy women with more sensitivity than measurements of spinal integral bone by DPA or of appendicular cortical bone by SPA or CCT.

Adult↗

Quantitative computed tomography for prediction of vertebral fracture risk.

Vertebral trabecular mineral content and peripheral cortical bone mineral were measured in 94 female and 44 male osteoporotic patients and compared to vertebral mineral values obtained for 323 control subjects in a cross-sectional study. The rate of change of spinal trabecular mineral with age (measured by quantitative computed tomography) in control females averaged 1.2% per year from age 20 to 80, with an accelerated loss demonstrated at the menopause. Trabecular bone mass in male controls declined an average 0.72% per year. Female osteoporotics had a mean decrement of 48 mg cm-3 (39%) compared to age-matched controls, whereas males were decreased 66 mg cm-3 (50%). Radial cortical bone was correlated with spinal mineral in osteoporotics for both males (r = 0.48) and females (r = 0.62). Vertebral compression fractures or wedging was generally absent in patients with vertebral mineral values above 110 mg cm-3, whereas almost all patients with values below 65 mg cm-3 had fractures. Quantitative computed tomography for measurement of vertebral trabecular bone mineral density is useful for defining those patients in whom the risk of vertebral fracture is increased.

Adult↗

The true composition of kidney stones passed during triamterene therapy.

The potassium-sparing agent triamterene and its metabolites have been identified as components of kidney stones passed by patients receiving that drug. We have analyzed 66 such kidney stones by use of quantitative thin-layer chromatography. The stones contained not only the unchanged triamterene but also significant amounts of an intermediate metabolite, hydroxytriamterene, and large amounts of the sulfate ester of hydroxytriamterene. Of the stones 49 per cent contained less than 5 per cent triamterene and its metabolites, and no stone comprised 100 per cent triamterene-derived material. Of all the triamterene-related material unchanged triamterene dominated. However, the relative fractions of triamterene and hydroxytriamterene in the kidney stones exceeded the relative fractions of these 2 components in the urine.

Chromatography, Thin Layer↗

Long-term estrogen replacement therapy prevents bone loss and fractures.

Although several case-control studies have shown an inverse association between postmenopausal estrogen use and fractures, quantitation of fracture incidence has been lacking. To quantify the degree to which estrogen replacement therapy prevents postmenopausal osteoporosis, a retrospective study was done comparing the occurrence of fractures in 245 long-term estrogen users and 245 case-matched controls, followed for an average of 17.6 years. Quantitative bone mineral assessments were obtained from 18 women using estrogen replacement therapy and their controls (average age, 73 years). Osteoporotic fracture incidence in estrogen users was 50% as great as in the controls (p less than 0.01). Estrogen users showed significantly greater bone mineral: 54.2% greater spinal mineral (p less than 0.0002), 19.4% greater forearm mineral (p less than 0.0005), and 15.6% greater metacarpal cortical thickness (p less than 0.005). Long-term estrogen replacement therapy confers significant protection against bone loss and fracture.

Bone Resorption↗

Osteoporosis: assessment by quantitative computed tomography.

The results presented in this article indicate that quantitative computed tomography provides a reliable means of evaluating and monitoring the many forms of osteoporosis and its various treatments. The greatest advantages of spinal QCT for noninvasive bone mineral measurement are its high precision, the high sensitivity of the vertebral spongiosa measurement site, and the potential for widespread application.

Adult↗