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F W Lafferty

Publications and source records attributed to F W Lafferty.

8 recordsLinked to original sources
PubMed1996

Correlations of dual-energy X-ray absorptiometry, quantitative computed tomography, and single photon absorptiometry with spinal and non-spinal fractures.

Controversy continues as to which method of measuring bone mineral density (BMD) best detects osteoporosis and best correlates with fractures of the spine, hip and elsewhere. To answer these questions the prevalence of fractures was carefully determined among 90 subjects (70 with osteoporosis, 6 with mild primary hyperparathyroidism, 1 with osteomalacia and 13 normals) and simultaneous measurements were made using spinal computed tomography (QCT), spinal anteroposterior (AP) and supine lateral dual X-ray absorptiometry (DXA), femoral neck and total hip DXA, and distal third radial DXA and single photon absorptiometry (SPA). The DXA measurements which had the greatest sensitivity in detecting osteoporosis (defined as a BMD lower than -2.5 SD of peak bone mass at age 30 years) were the supine lateral spine DXA (84%) and femoral neck DXA (75%); less sensitive were the DXA measurements of the distal third of the radius (61%) and AP spine (51%). DXA measurements of the femoral neck and distal third of the radius were more useful than spinal measurements in detecting the osteopenia of mild primary hyperparathyroidism. Vertebral compression fractures (VCF) correlated well with spinal QCT (r = 0.38) and lateral spine DXA (r = -0.41), but poorly with AP spine DXA (r = -0.17) and distal third radial DXA (r = -0.02). Non-spinal fractures correlated best with the distal third radial DXA (r = -0.42). In conclusion, spinal QCT, supine lateral spine DXA and femoral neck DXA are the best BMD methods to screen for osteoporosis, whereas AP spine DXA is a poor screening method in women over 60 years of age. Spinal QCT and lateral spine DXA correlate well with VCFs, whereas correlations of VCFs with AP spine DXA, femoral neck DXA and distal third radial DXA are poor.

Absorptiometry, Photon↗
PubMed1994

Postmenopausal estrogen replacement: a long-term cohort study.

To assess the long-term effects of estrogen replacement therapy (ERT) in 157 postmenopausal women, a prospective, nonrandomized, cohort study was conducted from 1964 to 1989. ERT consisted of 0.625 mg of conjugated equine estrogen daily for the first 25 days of each month without oral progesterone from 1964 to 1984. From 1984 to 1989 5 mg of medroxyprogesterone was added from day 14 to 25 of every sixth month in subjects with an intact uterus. The mean loss of height was significantly less among the ERT subjects after age 65 years and remained at 0.08 cm/year from age 56 to 80 years, whereas the loss of height accelerated among the control subjects to 0.19 cm/year from age 66 to 70, to 0.22 cm/year from age 71 to 75, and to 0.30 cm/year from age 76 to 80. The mean cortical bone density at the distal third of the radius was significantly greater among the ERT subjects compared to the control subjects with the difference representing a 12.0% higher bone density with ERT. The risk of both vertebral compression and peripheral fractures was significantly reduced in the ERT group (relative risk 0.28). The mean serum LDL cholesterol was 21% lower and the mean HDL cholesterol, 37% higher among ERT subjects compared to control subjects. Both ERT and total serum cholesterol had independent effects on the development of cardiovascular disease (myocardial infarction and stroke) in a multivariate analysis.

Adult↗
PubMed1991

Differential diagnosis of hypercalcemia.

The differential diagnosis of hypercalcemia has expanded to over 25 separate disease states, with primary hyperparathyroidism and malignancy accounting for 80-90% of all hypercalcemic patients. Primary hyperparathyroidism comprises the majority of hypercalcemic patients among the ambulatory population, but malignancy accounts for up to 65% of such patients in the hospital. Factors favoring primary hyperparathyroidism include a family history of hyperparathyroidism or multiple endocrine neoplasia, a history of childhood radiation to the head and neck, the postmenopausal state, a history of renal calculi or peptic ulcer, hypertension, the induction of hypercalcemia by thiazides, or an asymptomatic patient with a prolonged, stable mild hypercalcemia. The usefulness of the serum calcium, parathyroid hormone, chloride, phosphorus, serum 25-OHD, and 1,25-(OH)2D, and urinary calcium in the differential diagnosis of hypercalcemia is discussed. The pitfalls of an excessive reliance on the serum PTH in diagnosing hyperparathyroidism are stressed. The discriminant values of the serum calcium, chloride, phosphorus, and parathyroid hormone are explored, with the serum parathyroid hormone, chloride, and calcium proving most useful in separating primary hyperparathyroidism from other forms of hypercalcemia. Multivariate discriminant analysis using the serum calcium, phosphorus, and chloride and the hematocrit achieves an accuracy of 95-98% and is the most economical method of identifying hyperparathyroidism. The addition of the amino-terminal or intact PTH assay increases the accuracy to 99% and is essential in the presence of renal insufficiency.

Calcitriol↗
PubMed1989

Primary hyperparathyroidism. A review of the long-term surgical and nonsurgical morbidities as a basis for a rational approach to treatment.

We studied long-term morbidity after parathyroid surgery for primary hyperparathyroidism in 100 patients and compared it with the long-term morbidity of medical follow-up from the literature. The surgical treatment of primary hyperparathyroidism was associated with negative results of neck explorations, persistent hypercalcemia, recurrent hypercalcemia, permanent hypoparathyroidism, or recurrent laryngeal nerve damage in 13 (19%) of 68 patients followed up for five years postoperatively. A review of medical follow-up as reported in the literature showed progression of disease in 8% to 22% of patients followed up for five to ten years. There was no convincing evidence that mild primary hyperparathyroidism resulted in progressive osteoporosis or renal failure. Furthermore, no significant improvement in hypertension, peptic ulcer disease, or renal function followed successful parathyroid surgery. Unless future studies demonstrate progressive osteoporosis or renal damage in untreated, mild primary hyperparathyroidism, medical follow-up is a reasonable alternative to surgery in the compliant patient over 50 years of age.

Adult↗
PubMed1985

Post-menopausal estrogen replacement: the prevention of osteoporosis and systemic effects.

The long-term effects of estrogen replacements in post-menopausal women were assessed in 61 estrogen-treated and 63 control subjects followed prospectively for 3-16 yr (mean 8.6 yr). A loss of height of 1.3 cm (1/2") or more developed with twice the frequency among control as among estrogen-replaced subjects, with the major difference appearing after 65 yr of age. However, estrogen replacement was not an absolute protection against height loss, especially after 70 yr of age. Myocardial infarctions and abnormal electrocardiograms were significantly reduced among the estrogen-replaced compared to the control subjects, but further observations are needed. Long-term estrogen replacement in post-menopausal women reduces the development of spinal osteoporosis and may reduce the development of ischemic heart disease.

Adult↗
PubMed1981

Primary hyperparathyroidism. Changing clinical spectrum, prevalence of hypertension, and discriminant analysis of laboratory tests.

The clinical spectrum of 100 consecutive cases of surgically proved primary hyperparathyroidism treated from 1974 through 1978 was analyzed. Their laboratory test results were compared with 64 cases of other form of hypercalcemia using multivariate discriminant analysis. The clinical spectrum has dramatically shifted during the past three decades from renal calculi and bone disease to the asymptomatic patient discovered by routine serum chemical analysis. Hypertension was twice as common among hyperparathyroid patients as in the general population but failed to improve in 92% after parathyroidectomy. The most useful discriminant laboratory test in descending order of value were the serum chloride, serum calcium, hematocrit, serum phosphorus, and parathormone. Multivariate discriminant analysis of the serum calcium, phosphorus, chloride, and Hct provided a 98% degree of accuracy in separating hyperparathyroidism from other forms of hypercalcemia.

Adult↗