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H W Wahner

Publications and source records attributed to H W Wahner.

At least 37 records · Page 2Linked to original sources
PubMed1993

Long-term fracture prediction by bone mineral assessed at different skeletal sites.

Bone mineral density (BMD) was measured at the lumbar spine and cervical and intertrochanteric regions of the proximal femur by dual-photon absorptiometry and bone mineral content was assessed at the distal and midradius by single-photon absorptiometry in an age-stratified random sample of 304 Rochester, Minnesota women aged 30-94 years. Over follow-up extending to 10 years (median 8.3 years), 93 women experienced 163 new fractures. After adjusting for age, these bone mineral measurements predicted the likelihood of any incident fracture due to moderate trauma, with relative hazards varying from 1.4 to 1.6 per SD decrease in baseline bone mineral. A 1 SD decrease in lumbar spine BMD increased the risk of a new vertebral fracture comparably to a 17 year increase in age; a 1 SD decrease in femoral BMD was comparable to a 13-14 year increase in age on the risk of a hip fracture. We conclude that bone mineral measurements made at a variety of skeletal sites can predict the occurrence for at least 8-10 years of moderate trauma fractures of the sort that might be related to osteoporosis.

Absorptiometry, Photon↗
PubMed1993

Dual energy x-ray absorptiometry of implanted femora after cemented and press-fit total hip arthroplasty in a canine model.

The effect of a press-fit and cemented titanium alloy endoprosthesis on the measurement of bone mineral density (BMD) of the proximal femur in a canine model with dual energy x-ray absorptiometry (DXA) was determined. Seven regions of interest, corresponding to zones 1-7 according to Gruen et al., were measured. Eight unpaired femora were scanned with DXA before implantation (five separate scans per femur), after press-fitting with a titanium alloy femoral component (five separate scans per femur); and after cementing with the same component (five separate scans per femur). When the titanium alloy endoprosthesis was press-fit, the BMD of five of seven regions of the proximal femur increased significantly (range, 2.7-23.1%; mean, 11.2%), although the mean precision error of this measurement was not altered (before implantation, 1.1%; after press-fit 1.8%). Cementing of the implant caused a variable effect on BMD, resulting in a decrease in distal regions where cortical bone was relatively thin compared with the cement mantle (regions 3, 4, and 5) and in an increase in the other regions. Cementing of the implant significantly increased the mean precision error of measurement to 7.2% (range, 1.1-12.6%).

Absorptiometry, Photon↗
PubMed1993

Influence of breastfeeding and other reproductive factors on bone mass later in life.

The influence of reproductive factors on bone mass at six skeletal sites was assessed in an age-stratified random sample of white women residing in Rochester, Minnesota. After age-adjustment, whether or not women had ever breastfed, total duration of breastfeeding and duration of breastfeeding per child were not associated with reduced bone mineral, but breastfeeding for more than 8 months was associated with greater bone mineral at some sites. There were no consistent effects on bone mineral, after adjusting for age, of gravidity or parity, age at menarche, age at first delivery, use of oral contraceptives or estrogen replacement therapy, various sex hormones, nor any of the other reproductive factors assessed. There was a strong protective effect of obesity, which was also correlated with a number of the reproductive variables. While animal studies suggest that pregnancy and lactation may be associated with calcium loss from the skeleton, these data indicate that such factors have little long-term impact on bone mass in humans and little potential for identifying women at high risk of osteoporosis later in life.

Adult↗
PubMed1993

Preventive effects of transdermal 17 beta-estradiol on osteoporotic changes after surgical menopause: a two-year placebo-controlled trial.

OBJECTIVE: The purpose of our study was to evaluate the effects of three dosages of transdermally administered 17 beta-estradiol on markers of bone loss in women who had recently undergone surgical menopause. STUDY DESIGN: This was a 2-year, randomized, double-blind, placebo-controlled study that reviewed 127 women stratified by age. Biochemical indicators of bone metabolism in urine and serum were periodically assessed, as was bone mineral content of the lumbar spine and radius. Statistical analysis examined the percent changes from baseline in bone mineral density by using an analysis of covariance with treatment as a factor and the baseline value as a covariant, by performing all-pairwise comparisons among the three estradiol groups, and by testing for a linear dose-response relationship. RESULTS: After 2 years of therapy, a significant dose-response relationship was detected. CONCLUSION: This 2-year study demonstrates that transdermally administered 17 beta-estradiol is a safe and effective regimen for preventing bone loss in recently postmenopausal women.

Adult↗
PubMed1993

Assessment of body composition with use of dual-energy x-ray absorptiometry: evaluation and comparison with other methods.

Dual-energy x-ray absorptiometry (DEXA) is a relatively new method of assessing body composition in humans. In the current study, DEXA was analyzed for accuracy and precision by using both anthropomorphic phantoms and a combination of body composition techniques in humans. Satisfactory precision for measurement of total body fat, fat-free mass, and total body bone mineral could be demonstrated in vivo and in vitro. Predictions of lean body mass in humans on the basis of DEXA, total body water, and total body potassium were significantly different. The results of multiple regression analysis suggested that a component of total body water was related to body potassium, and another component was predicted by body fat. In addition, extracellular fluid volume, as measured by the bromide space technique, was significantly associated with both fat-free mass and fat mass as measured by DEXA. These findings have implications for the interpretation of body composition data in humans.

Absorptiometry, Photon↗
PubMed1993

Noninvasive evaluation of the lymphatic system with lymphoscintigraphy: a prospective, semiquantitative analysis in 386 extremities.

PURPOSE: Lymphoscintigraphy has emerged as the diagnostic test of choice in patients with suspected lymphedema. To assess the lymphatic circulation of 386 extremities in 188 patients, we prospectively recorded a semiquantitative index of lymphatic transport in addition to visual evaluation of lymphoscintigraphy image patterns. METHODS: Sixty-one male and 127 female patients were studied (mean age 48 years, range 13 to 87 years). Twenty had upper extremity swelling, and 168 had lower extremity swelling. The disease was bilateral in 60 patients. Lymphoscintigraphy was performed by injecting a mean of 503 microCi of technetium 99m-antimony trisulfide colloid subcutaneously into the second interdigital space of the extremity. Time for transport to regional lymph nodes, appearance of lymph vessels and nodes and distribution pattern were scored. These scores were compiled into a modified Kleinhans transport index (TI). To assess the venous circulation, 155 patients underwent evaluation of the venous system by impedance plethysmography, ultrasonography, or contrast venography. RESULTS: The mean TI (+/- SEM) in 79 asymptomatic extremities was 2.6 +/- 0.5, with 66 (83.5%) demonstrating normal lymphoscintigraphy pattern (TI < 5). Patients with clinical diagnosis of lymphedema (n = 124) had a mean TI of 23.8 +/- 1.5; 81.5% of these were greater than 5. Fifty-six patients (30%) had primary and 68 (36%) had secondary lymphedema. (TI of 26 +/- 3.5 and 22.1 +/- 1.9, respectively, p = NS). Patients without any lymphatic transport (TI of 45) were more likely to have cellulitis in their history (p < 0.05). Contrast lymphangiography in six patients correlated with lymphoscintigraphy. Sixty-four patients (34%) had swelling without lymphedema (venous edema, cardiac edema, lipedema, etc.; TI of 1.9 +/- 0.4, p < 0.001). Of the 41 patients with abnormal venous studies, 18 (44%) had an elevated TI. CONCLUSIONS: Semiquantitative evaluation of the lymphatic transport with lymphoscintigraphy reliably depicts abnormalities in the lymphatic circulation. Lymphoscintigraphy excluded lymphedema as a cause of leg swelling in one third of our patients.

Adolescent↗
PubMed1992

Treatment of postmenopausal osteoporosis with transdermal estrogen.

OBJECTIVE: To evaluate the tolerance and effectiveness of transdermal estrogen for women with established postmenopausal osteoporosis and vertebral fractures. DESIGN: Double-blind, randomized, placebo-controlled clinical trial lasting 1 year. SETTING: Referral-based outpatient clinic. PATIENTS: Seventy-five postmenopausal women, 47 to 75 years of age, with one or more vertebral fractures due to osteoporosis. INTERVENTIONS: Thirty-nine women received dermal patches delivering 0.1 mg of 17 beta-estradiol for days 1 to 21 and oral medroxyprogesterone acetate for days 11 to 21 of a 28-day cycle. Another 39 women received placebo. MEASUREMENTS: Bone turnover assessed by biochemical markers and iliac bone histomorphometry; bone loss assessed by serial measurement of bone density; and vertebral fracture rate. RESULTS: Compared with the placebo group, the median annual percentage change in bone mineral density in the estrogen group reflected increased or steady-state bone mineral density at the lumbar spine (5.3 compared with 0.2; P = 0.007), femoral trochanter (7.6 compared with 2.1; P = 0.03), and midradius (1.0 compared with -2.6, P less than 0.001) but showed no significant difference at the femoral neck (2.6 compared with 1.4; P = 0.17). Estrogen treatment uniformly decreased bone turnover as assessed by several methods including serum osteocalcin concentration (median change, -0.35 compared with 0.02 nmol/L; P less than 0.001). Histomorphometric evaluation of iliac biopsy samples confirmed the effect of estrogen on bone formation rate per bone volume (median change, -12.9 compared with -6.2% per year; P = 0.004). Also, 8 new fractures occurred in 7 women in the estrogen group, whereas 20 occurred in 12 women in the placebo group, yielding a lower vertebral fracture rate in the estrogen group (relative risk, 0.39; 95% CI, 0.16 to 0.95). CONCLUSIONS: Transdermal estradiol treatment is effective in postmenopausal women with established osteoporosis.

Administration, Cutaneous↗
PubMed1992

Is caffeine consumption a risk factor for osteoporosis?

High caffeine consumption has been proposed as a risk factor for osteoporotic fracture, but the evidence associating high caffeine intake with low bone density is inconsistent. We therefore examined the influence of caffeine consumption on bone mineral at six skeletal sites in an age-stratified random sample of white women residing in Rochester, Minnesota. After age adjustment, there was no association between overall caffeine consumption and bone mineral at five of the six sites. In the femoral shaft, however, there was a statistically significant interaction between age and caffeine consumption so that high caffeine intake was associated with slight reductions in bone mineral among elderly subjects but with modestly increased bone mineral at younger ages. When caffeine intake was categorized by source, no consistent influence of coffee, tea, or other caffeinated beverage consumption could be detected on bone mineral. Caffeine intake was, however, positively associated with cigarette smoking and alcohol consumption. After adjusting for age, caffeine consumption was not correlated with biochemical indices of bone turnover, circulating concentrations of estradiol and estrone, or other dietary and musculoskeletal variables. These data suggest that caffeine intake in the range consumed by a representative sample of white women is not an important risk factor for osteoporosis. Among elderly women, however, in whom calcium balance performance is impaired, high caffeine intake may predispose to cortical bone loss from the proximal femur.

Adult↗
PubMed1992

Assessing hip fracture risk in a population-based health survey: the NHANES III osteoporosis component.

A unique study of osteoporotic hip fracture risk, currently being conducted as part of a national health survey of the United States population, is described. The osteoporosis component of the third National Health and Nutrition Examination Survey (NHANES III) will provide data on multiple risk factors for hip fracture, including bone density of the proximal femur, from a nationally representative sample of adults that includes the very old. The minimum age for inclusion in the component is 20 years, so risk factors can be examined across the adult age range. The component includes men as well as women, and blacks and Mexican Americans as well as non-Hispanic whites. Finally, a longitudinal follow-up of the cohort will allow risk factor data to be related to subsequent hip fracture occurrence.

Adult↗
PubMed1992

Osteoporosis and calcification of the aorta.

In an age-stratified random sample of 200 Rochester, Minnesota women, the prevalence of aortic calcification rose with aging, as did the prevalence of vertebral fractures, while bone mass fell. The statistically significant positive association of aortic calcification with vertebral fractures and the negative associations with bone mass at six skeletal sites were mainly accounted for by age. After age-adjustment, the only association remaining was a negative one between calcified aortic plaques and bone mineral density (BMD) of the lumbar spine (P < 0.05). Aortic calcification was not associated with any measures of calcium metabolism, after adjusting for age, except for a slight negative association between linear aortic calcifications and 25(OH) vitamin D levels (P < 0.05). BMD values of the lumbar spine were somewhat greater than predicted for age in women with severe aortic calcification, but similar findings were seen at other skeletal sites and none of the differences was statistically significant. While overestimation of bone mass was generally minimal, severe aortic calcification may distort lumbar spine assessments in a minority of postmenopausal women.

Adult↗
PubMed1992

Pernicious anaemia as a risk factor for osteoporosis.

1. If gastric acid is necessary for the absorption of dietary calcium, the total absence of gastric acid secretion that occurs in pernicious anaemia could result in bone loss. To investigate this, we measured calcium absorption and bone density in 21 postmenopausal women (ages 51-76 years) with pernicious anaemia and in 24 normal postmenopausal women (ages 51-79 years). 2. Relative to the normal women, in the women with pernicious anaemia the bone mineral density of the lumbar spine was decreased by 16% (P less than 0.001). 3. After adjustment for age and body weight, lumbar spine bone mineral density correlated with the serum concentration of group 1 pepsinogens (a group of proteins produced by the gastric fundus) (r = 0.61, P less than 0.01). 4. Despite achlorhydria, the women with pernicious anaemia had normal true fractional calcium absorption and normal serum levels of parathyroid hormone and 1,25-dihydroxyvitamin D. 5. We conclude that gastric acid is not required for the absorption of dietary calcium. Thus, the loss of cancellous bone must be caused by some mechanism yet to be identified.

Achlorhydria↗
PubMed1992

Asymmetric cortical degenerative syndromes: clinical and radiologic correlations.

Eight patients presented with slowly progressive focal neurologic syndromes that conformed to one of three clinically defined categories: progressive nonfluent aphasia (three patients), progressive perceptual-motor impairment (four patients), and progressive frontal lobe syndrome (one patient). Planar MRI and MRI-based surface or volume renderings demonstrated focal areas of atrophy that correlated well with clinical deficits. Single-photon emission computed tomography (SPECT) showed areas of cortical hypoperfusion that corresponded to focally atrophic regions revealed by MRI, but abnormal areas with SPECT were larger than those suggested by MRI. MRI and SPECT are useful in defining the regional structural and functional cerebral abnormalities that underlie slowly progressive focal neurologic syndromes caused by asymmetric cortical degeneration.

Aged↗
PubMed1992

Cyst decompression surgery for autosomal dominant polycystic kidney disease.

A prospective study was undertaken to evaluate the efficacy of surgical cyst decompression for retarding the progression of renal failure and for the management of chronic pain associated with autosomal dominant polycystic kidney disease (ADPKD). Thirty patients with ADPKD and pain (14 patients), renal insufficiency (4 patients), or both (12 patients) underwent unilateral (19 patients) or bilateral (11 patients) cyst reduction surgery. The patients were monitored for 21 +/- 2 months postoperatively. The probability of being painfree was 80% at 1 yr and 62% at 2 yr. Preoperative and 1-to 3-month postoperative serum creatinine levels and GFR (clearance of insulin or (125I) iothalamate) were not significantly different (2.2 +/- 0.3 versus 2.2 +/- 0.3 mg/dL and 49 +/- 8 versus 54 +/- 9 mL/min/1.73 m2, respectively). One-year serum creatinine levels remained unchanged in patients with normal preoperative renal function (1.0 +/- 0.07 versus 1.0 +/- 0.05 mg/dL), whereas those with preoperative progressive renal insufficiency had no difference in the mean slope of reciprocal serum creatinine plots preceding and after surgery (-0.008 +/- 0.001 versus -0.009 +/- 0.002 dL/mg/month). In patients who underwent unilateral surgery, split function isotope scans showed no change in function of the operated kidney when compared with the nonoperated kidney. Surgical cyst decompression provides effective relief of chronic pain without compromising renal function. However, the data in this article do not support the use of this procedure to slow progression of renal insufficiency in ADPKD.

Adult↗
PubMed1991

Classification of vertebral fractures.

Although it is a cardinal feature of involutional osteoporosis, there is often disagreement on what constitutes a vertebral fracture. We measured vertebrae T4-L5 in 52 healthy women to develop a normal range (mean +/- 3 SD) for vertebral shape and used these data to assess the prevalence of vertebral fractures. We classified vertebral fractures by type of deformity (wedge, biconcavity, or compression) and further by the degree of deformity (grades 1 and 2). In 195 postmenopausal women who were an age-stratified random sample of the Rochester population (ages 47-94), 40 (21%) had vertebral fractures (mean, 2 per person). There was a similar number of compression and wedge fractures, and grade 2 fractures were as common as grade 1. In a referral sample of 74 women with suspected osteoporosis, 62 (84%) had vertebral fractures (mean, 3.3 per person). Wedge fractures were most common, and grade 2 fractures were more common than grade 1. The distribution of type and grade of fractures differed between the two patient groups (P less than 0.01). Bone mineral density of the lumbar spine was related to mean fracture grade (r = -0.33, P less than 0.05) and to fracture number (r = -0.57, P less than 0.001) but not to fracture type. We conclude that a comprehensive approach is required in describing vertebral fractures. Using this approach we found distortion in the fracture characteristics of women referred to an osteoporosis clinic compared to women in the community.

Aged↗
PubMed1991

Rates of vertebral bone loss before and after liver transplantation in women with primary biliary cirrhosis.

Atraumatic fractures caused by osteoporosis may be a serious complication of primary biliary cirrhosis. Mean (+/- S.D.) bone mineral density in the lumbar spine in 210 ambulatory women with primary biliary cirrhosis was 1.02 +/- 0.19 gm/cm2, 7% lower than that in 139 age-matched normal women (after adjustment for age and body weight) (p less than 0.001). Bone mineral density in the lumbar spine was inversely related to a risk score index of liver disease severity (r = -0.29, p less than 0.001). The mean rate of bone loss in 105 of these 210 women was 2%/yr +/- 4%/yr, twice as great as in the 139 normal women (p less than 0.02). In 20 women with primary biliary cirrhosis followed up after orthotopic liver transplantation, bone mineral density in the lumbar spine decreased at 3 mo (p less than 0.01), and this decrease may have resulted in atraumatic fractures in 13 of them. Bone mineral density in the lumbar spine then increased (p less than 0.01) so that by 12 mo the median bone mineral density in the lumbar spine was similar to that before transplantation and by 24 mo it was 5% above it. Therefore we conclude that the progressive bone loss observed in primary biliary cirrhosis (which is further accentuated immediately after transplantation) may be halted, and the bone mass may be restored toward normal within 2 to 3 yr after orthotopic liver transplantation.

Absorptiometry, Photon↗
PubMed1991

An evaluation of forearm bone mineral measurement with dual-energy X-ray absorptiometry.

Dual-energy x-ray absorptiometry (DEXA) has been reported to be a valuable means of bone mineral measurement of the lumbar spine and hip. In order to determine whether DEXA could be as useful for bone mineral analysis of the forearm, we compared its accuracy, precision and measurement performance to single-photon absorptiometry (SPA). There was high correlation between these techniques for integral bone mineral density in standard aluminum tubes (r = 0.99) and 30 adult volunteers or patients with osteoporosis (r = 0.95). The mean short-term precision of DEXA was 0.9% in vitro and about 1.5% in vivo. DEXA produced excellent bone images which enhance long-term in vivo precision. The measurement performance of both instruments was largely unaffected by localized fat deposits or increases in forearm thickness or proportion of fat subcutaneously. We conclude that DEXA is a clinically useful alternative to SPA for forearm bone mineral assessment.

Absorptiometry, Photon↗
PubMed1990

Effect of fluoride treatment on the fracture rate in postmenopausal women with osteoporosis.

Although fluoride increases bone mass, the newly formed bone may have reduced strength. To assess the effect of fluoride treatment on the fracture rate in osteoporosis, we conducted a four-year prospective clinical trial in 202 postmenopausal women with osteoporosis and vertebral fractures who were randomly assigned to receive sodium fluoride (75 mg per day) or placebo. All received a calcium supplement (1500 mg per day). Sixty-six women in the fluoride group and 69 women in the placebo group completed the trial. As compared with the placebo group, the treatment group had increases in median bone mineral density of 35 percent (P less than 0.0001) in the lumbar spine (predominantly cancellous bone), 12 percent (P less than 0.0001) in the femoral neck, and 10 percent (P less than 0.0001) in the femoral trochanter (sites of mixed cortical and cancellous bone), but the bone mineral density decreased by 4 percent (P less than 0.02) in the shaft of the radius (predominantly cortical bone). The number of new vertebral fractures was similar in the treatment and placebo groups (163 and 136, respectively; P not significant), but the number of nonvertebral fractures was higher in the treatment group (72 vs. 24; P less than 0.01). Fifty-four women in the fluoride group and 24 in the placebo group had side effects sufficiently severe to warrant dose reduction; the major side effects were gastrointestinal symptoms and lower-extremity pain. We conclude that fluoride therapy increases cancellous but decreases cortical bone mineral density and increases skeletal fragility. Thus, under the conditions of this study, the fluoride-calcium regimen was not effective treatment for postmenopausal osteoporosis.

Aged↗