Biomedical subjects

W M O'Fallon

Publications and source records attributed to W M O'Fallon.

At least 19 recordsLinked to original sources

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

Incidence and natural history of primary systemic amyloidosis in Olmsted County, Minnesota, 1950 through 1989.

No reports of the incidence rates for primary systemic amyloidosis (AL) have come to our attention. Records of all residents of Olmstead County, Minnesota, with a diagnosis of amyloidosis were obtained from the Mayo Clinic and its affiliated hospitals, as well as other medical groups that might have seen local patients for the period January 1, 1950 to December 31, 1989. Twenty-one patients fulfilled the criteria for the diagnosis of AL. The median age was 73.5 years, and 62% were men. In all but one patient the diagnosis was made ante mortem. The clinical data of the 21 patients were similar to those referral patients with AL seen at Mayo Clinic. Immunohistochemical stains were positive for monoclonal light chains in the amyloid deposits in 15 of the 21 cases. In six cases, tissue was not available for immunohistochemical studies. Three of the six patients without immunohistochemical stains had a free monoclonal lambda light chain in the urine, and the other three had a monoclonal serum protein. Immunoelectrophoresis/immunofixation detected a monoclonal (M)-protein in the serum of 16 of 17 patients tested. A monoclonal light chain was found in the urine of 10 of 15 patients. The overall sex- and age-adjusted rate per million person-years was 6.1 from 1950 to 1969 and 10.5 from 1970 to 1989. The similarity of these rates suggests no significant increase over time.

Aged↗

PubMed1992

Ankylosing spondylitis in Rochester, Minnesota, 1935-1989. Is the epidemiology changing?

OBJECTIVE: To determine trends in the incidence and clinical presentation of ankylosing spondylitis first diagnosed between 1935 and 1989 among residents of Rochester, Minnesota, and in the survival of the patients. METHODS: Population-based descriptive study. RESULTS: The overall age- and sex-adjusted incidence rate was 7.3 per 100,000 person-years (95% confidence interval 6.1-8.4). The rate tended to decline between 1935 and 1989, but there was little change in the age at symptom onset or diagnosis over the 55-year study period. Overall survival was not decreased up to 28 years following diagnosis. CONCLUSION: These data indicate that there is a constancy in the epidemiologic characteristics of ankylosing spondylitis and suggest that previously study results indicating changes may have been due to biases in patient selection and study design.

Adolescent↗

PubMed1992

Incidence of clinically diagnosed vertebral fractures: a population-based study in Rochester, Minnesota, 1985-1989.

Vertebral fractures are the classic hallmark of osteoporosis, yet little is known of their epidemiology. The incidence of clinically diagnosed vertebral fractures was therefore directly assessed in the predominantly white (European descent) population of Rochester, Minnesota. Altogether, 341 Rochester residents were radiologically diagnosed for the first time with one or more vertebral fractures in the 5 year study period, 1985-1989. The overall age- and sex-adjusted incidence rate was 117 per 100,000 person-years (95% CI, 105 to 130). The age-adjusted rate in women (145 per 100,000 person-years) was almost twice that in men (73 per 100,000 person-years). Of all fractures, 47 (14%) followed severe trauma, 282 (83%) followed moderate or no trauma, and 12 (3%) were pathologic. Incidence rates for fractures following moderate trauma were higher in women than in men and rose steeply with age in both genders. In contrast, fractures following severe trauma were more frequent in men, and their incidence increased less with age. These Rochester rates are greater than those previously reported from studies in Britain and Sweden but lower than the incidence rates extrapolated from a prevalence study in this population.

Adult↗

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

Risk of fractures in patients with pernicious anemia.

In a series of postmenopausal women previously studied by our group, pernicious anemia was associated with reduced bone mineral density of the spine and with vertebral fractures. To determine whether osteoporotic fractures represent an important clinical problem for such patients, we conducted a population-based retrospective cohort study of all Rochester, Minnesota residents newly diagnosed with pernicious anemia from 1950 through 1979. These 131 individuals were followed through the inpatient and outpatient records of all medical care providers in the community for 1550 person-years. In comparison with fracture rates from the general community, patients with pernicious anemia had a 1.9-fold increase in proximal femur fractures, a 1.8-fold increase in vertebral fractures, and a 2.9-fold increase in distal forearm fractures (all p less than 0.05). Increases in the risk of proximal humerus and pelvis fractures were not statistically significant. Clinicians should be aware that pernicious anemia is associated with an increased risk of osteoporotic fractures, but the mechanism is unknown.

Adult↗

PubMed1992

Secular trends in the incidence of postmenopausal vertebral fractures.

Several studies suggest secular increases in hip fracture incidence through this century, but little is known about such trends for vertebral fracture. We have examined changes in the incidence of clinically ascertained vertebral fractures among Rochester, Minnesota residents aged 35-69 years, that were first diagnosed between 1950 and 1989. Our results indicate no overall increase in incidence over the 40-year period. Categorization of fractures according to the level of preceding trauma, however, revealed a significant increase in the incidence of fractures following moderate trauma among women aged 60-69 years. This increase occurred between 1950 and 1964, and leveled off thereafter. Rates for severe trauma fractures among postmenopausal women, and for vertebral fractures from any cause among younger men and women, remained stable. The rise in moderate trauma fractures in postmenopausal women paralleled that for hip fractures in Rochester and began to plateau at around the same time. It might have resulted from increased diagnosis of vertebral fractures, but the increase in hip fracture incidence is inconsistent with this explanation. An increase in the prevalence of osteoporosis, however, might account for the trend in both types of fractures.

Adult↗

PubMed1992

Influence of coronary heart disease on morbidity and mortality after carotid endarterectomy: a population-based study in Olmsted County, Minnesota (1970-1988)

To evaluate the prognostic importance of coronary artery disease among patients undergoing carotid endarterectomy, 177 residents of Olmsted County, Minnesota who underwent carotid endarterectomy during the period 1970 through 1988 were followed up to July 1, 1989. Patients were stratified as to the presence (n = 64) or absence (n = 93) of overt coronary artery disease or prior myocardial revascularization (n = 20) at the time of endarterectomy. At 30 days after carotid endarterectomy, there were no significant differences between patients with or without coronary artery disease in the occurrence of death, myocardial infarction or stroke. Kaplan-Meier estimate of 8-year relative survival after carotid endarterectomy (assessed as a percent of survival in age- carotid endarterectomy (assessed as a percent of survival in age- and gender-matched control subjects) was 89% in those without and 75% in those with overt coronary artery disease. Of the 59 total deaths, 29 (49%) had a cardiac cause and 4 (7%) were due to stroke (p less than 0.0001). The cumulative incidence of a cardiac event at 8 years after carotid endarterectomy was greater in those with than in those without overt coronary artery disease (61% vs. 25%, p less than 0.0001). In multivariable analysis, uncorrected coronary artery disease and diabetes were the only independent predictors of subsequent cardiac events, whereas age was the only independent predictor of death. These population-based data suggest that carotid endarterectomy can be safely undertaken in patients with stable coronary artery disease. In long-term follow-up of these patients, coronary rather than cerebral vascular disease is the most frequent cause of morbidity and mortality. Thus, these data lend strong support to the concept of early identification and management of coronary artery disease in patients undergoing carotid endarterectomy.

Cohort Studies↗

PubMed1992

Conditions associated with carpal tunnel syndrome.

With use of a comprehensive medical records-linkage system, we identified the comorbid conditions and risk factors in the residents of Rochester, Minnesota, who had a diagnosis of carpal tunnel syndrome during 1961 through 1980. In 43.2% of the 1,016 patients, no associated conditions were found on review of the medical records, whereas associated conditions were documented in 56.8%. The most frequent of these conditions were Colles' fracture, rheumatoid arthritis, hormonal agents or oophorectomy (or both), diabetes mellitus, and, among men, occupations that involved excessive use of the hands. Rheumatoid arthritis, diabetes mellitus, and pregnancy were significantly more frequent among the study patients with carpal tunnel syndrome than in the general population of Rochester, Minnesota. The standardized morbidity ratio was 3.6 for rheumatoid arthritis, 2.3 for diabetes mellitus, and 2.5 for pregnancy. The population attributable risk for pregnancy among women 15 to 44 years old was 7.0%. The standardized morbidity ratio for polymyalgia rheumatica was not significantly increased.

Adolescent↗

PubMed1992

Fracture risk in patients with parkinsonism: a population-based study in Olmsted County, Minnesota.

In this population-based retrospective cohort study, the 138 Olmsted County, Minnesota residents first diagnosed with Parkinson's disease during 1967-79 were matched by age and sex to an equal number of control subjects from the community. Fractures were assessed through review of each subject's complete (inpatient and outpatient) medical records. At the time of diagnosis, County residents with parkinsonism were no more likely to have a history of selected fractures than control subjects (32% in each group). Subsequently, 33% of cases and 20% of controls experienced one or more new fractures during 696 person-years of follow-up (p = 0.008). The greatest increase in risk was seen for proximal femur fractures, confirming previous case-control studies. By 10 years after diagnosis, an estimated 27% of the parkinsonism cohort had experienced a new hip fracture. The pattern of fractures that was observed suggested that the increased risk was due more to specific types of falls than to disuse osteoporosis.

Aged↗

PubMed1992

Relationship of cardiac disease to stroke occurrence, recurrence, and mortality.

BACKGROUND AND PURPOSE: This is a study of cardiac diseases associated with the 1,382 cases of first cerebral infarction in residents of Rochester, Minn., during 1960-1984. METHODS: This is a population-based study in Rochester, Minn., for which the medical record-linkage system was used to identify cardiac disease among patients with first cerebral infarction. RESULTS: There were 318 patients (23%) who had at least one major potential cardiac source of emboli. The proportion of patients with a cardiac source of emboli was significantly higher among patients older than age 75 years (29%) than among younger patients (17%). The 30-day stroke recurrence rate among patients with a cardiac source of emboli (2%) was not significantly different than that among those without a cardiac source of emboli (2%). Among patients with a cardiac source of emboli, there was no difference in the probability of stroke at 30 days and at 90 days for those treated or not treated with anticoagulants. During the first 30 days after cerebral infarction, the risk of death in patients with a cardiac source of emboli (23%) was 14 times that of recurrent stroke. The risk of death at 30 days in patients without a cardiac source of emboli was 8%. CONCLUSIONS: Significant independent predictors of death (Cox proportional-hazards analysis) were age, prior myocardial infarction, atrial fibrillation present at onset of stroke, congestive heart failure before the stroke, and an age x congestive heart failure interaction. The only significant independent predictors of recurrent stroke were cardiac valve disease and congestive heart failure.

Cerebrovascular Disorders↗

PubMed1992

A community-based study of the epidemiology of asthma. Incidence rates, 1964-1983.

To determine whether the incidence of asthma had increased in Rochester, Minnesota, from January 1, 1964 through December 31, 1983, we used a population-based computer-linked medical diagnosis system to identify individual medical records with diagnosis of asthma or other conditions mimicking asthma. All records were reviewed using explicit predetermined diagnostic criteria; we identified 3,622 incident cases of asthma, including definite asthma (n = 1,547), probable asthma (n = 952), and single wheezing episodes (n = 1,123). The annual age- and sex-adjusted incidence of definite + probable asthma rose from 183 per 100,000 in 1964 to 284 per 100,000 in 1983. This rise was entirely accounted for by increased incidence rates in children and adolescents (age range, 1 to 14 yr); incidence rates for infants younger than 1 yr of age and for adults remained constant. For definite + probable asthma cases, the incidence rates for males were higher than for females from infancy through 9 yr of age and for persons older than 50; incidence rates for females were higher than for males from 15 through 49 yr of age. The median age at onset was 3 yr for males and 8 yr for females. We conclude that asthma begins in early childhood, with a higher incidence and earlier onset in males, and that the increase in incidence rates seen from 1964 to 1983 occurred only in children and in adolescents.

Age Factors↗

PubMed1992

Incidence of migraine headache: a population-based study in Olmsted County, Minnesota.

To determine the incidence of clinically detected migraine headache in the defined population of Olmsted County, MN, 1979-1981, we screened over 6,400 patient records from several diagnostic rubrics using the unique resources of the Rochester Epidemiology Project for population-based studies. We identified 629 Olmsted County residents who fulfilled the International Headache Society's 1988 criteria for newly diagnosed migraine headache between 1979 and 1981. The overall age-adjusted incidence was 137 per 100,000 person-years for males and 294 per 100,000 person-years for females. The highest incidence in females was among those aged 20 to 24 years (689 per 100,000 person-years), and in males, the highest incidence was among those aged 10 to 14 years (246 per 100,000 person-years). From 1979 to 1981, there was a striking increase in the age-adjusted incidence in those under 45 years of age: the incidence increased 34% in women and 100% for men. This is the first population-based study of migraine incidence across all ages.

Adolescent↗

PubMed1992

Dialysis support of patients with primary systemic amyloidosis. A study of 211 patients.

BACKGROUND: The study assessed dialysis support in patients with primary systemic amyloidosis without associated multiple myeloma in whom renal insufficiency developed. METHODS: The study group consisted of 211 patients with biopsy-proved primary systemic amyloidosis examined at the Mayo Clinic, Rochester, Minn. No patient was lost to follow-up. RESULTS: Thirty-seven (18%) of the patients received dialysis therapy. Of those presenting with renal amyloid, one third received dialysis. The median time from diagnosis to initiation of dialysis was 13.8 months. The median survival for patients from the start of dialysis was 8.2 months. There was no survival difference between hemodialysis (n = 27) and peritoneal dialysis (n = 10). The most important predictors of which patients would ultimately require dialysis were the 24-hour urinary protein loss and serum creatinine values at the time amyloidosis was diagnosed. None of the patients seen at diagnosis with a normal serum creatinine value and proteinuria of less than 2 g/d required dialysis during follow-up. Of the 37 patients who received dialysis, 31 died, and 21 of the 31 died as a result of extrarenal progression of their systemic amyloidosis. Fifteen of the 31 deaths were a result of cardiac amyloidosis. All long-term survivors had normal echocardiograms without evidence of amyloid. CONCLUSION: Eighteen percent of patients with primary amyloidosis undergo dialysis. The 24-hour urinary protein loss and creatinine values are helpful in predicting which patients eventually will require dialysis. The median survival for patients starting dialysis is less than 1 year. Patients whose two-dimensional echocardiograms are normal are most likely to derive long-term benefit from dialysis.

Aged↗

PubMed1992

Risk of age-related fractures in patients with primary hyperparathyroidism.

BACKGROUND: Bone mass is reduced, but the influence of primary hyperparathyroidism (HPT) on fracture risk is controversial. We addressed this issue in a population-based retrospective cohort study. METHODS: Ninety residents of Rochester, Minn, were first diagnosed with HPT in 1965 through 1976 and an equal number of age- and sex-matched control subjects from the community were identified. Fractures were assessed through review of each subject's complete (inpatient and outpatient) medical records in the community. RESULTS: Prior to the date of diagnosis, Rochester residents with HPT were more likely to have a history of fractures than were matched control subjects from the same population (30% vs 18%). Subsequently, 36% of cases and 31% of control subjects experienced one or more new fractures during 1072 person-years of follow-up; survival free of a new fracture was almost the same in the two groups. Women had more fractures than men, and fracture rates increased with age. Fractures appeared to be somewhat more frequent in those with baseline serum calcium levels of 2.74 mmol/L or more, in those with comorbid conditions possibly due to HPT and in those who did not undergo parathyroidectomy, but these differences were not statistically significant. In a multivariate analysis, only age at diagnosis was an independent predictor of fracture risk, with a 36% increase in risk per 10-year increase in age. CONCLUSIONS: Overall fracture risk was increased prior to diagnosis of HPT but not afterward. Because the numbers involved were small, however, we cannot exclude an increased likelihood of fractures in certain subgroups of HPT patients.

Age Factors↗

PubMed1992

Epidemiology of Lyme disease in Olmsted County, MN, 1975-1990.

Lyme disease has been reported in Minnesota since 1980. Until now, it has not been regarded as endemic in Olmsted County. We reviewed the medical records of all 68 cases of Lyme disease diagnosed in residents of Olmsted County for 1980-1990. Only 17 of the 68 cases met Centers for Disease Control surveillance criteria for definite Lyme disease (13 men, 4 women). Of these 17 cases, 3 were likely acquired in Olmsted County. The age and sex adjusted incidence rate was 2.3/100,000 (95% CI 1.1-3.4). Although reporting of Lyme disease is mandatory in Minnesota, only 7 suspected or definite cases were actually reported to public health officials. Of these, 4 met the case definition. In this population Lyme disease was both over-diagnosed and underreported. This observation questions current data and could have important health policy implications if confirmed nationally.

Adolescent↗

PubMed1991

Predictors of intracranial carotid artery atherosclerosis. Duration of cigarette smoking and hypertension are more powerful than serum lipid levels.

The effect of cigarette smoking on intracranial internal carotid artery atherosclerosis (ICAS) was studied by obtaining cigarette smoking histories and data on other potential predictors, including serum lipid estimations, for consecutive patients undergoing carotid arteriography. The duration of cigarette smoking was the most significant independent predictor of the presence of ICAS. Other independently significant predictors of ICAS were hypertension, diabetes mellitus, and current systolic blood pressure. The interaction of diabetes and duration of smoking was a significant negative predictor. In patients for whom serum lipid values were available, lower levels of apolipoprotein A-I were associated with a higher risk of having ICAS. However, the effect of apolipoprotein A-I as a predictor of the presence of ICAS was far outweighted by the effects of duration of smoking and hypertension.

Adult↗

PubMed1991

Serum lipids and lipoproteins are less powerful predictors of extracranial carotid artery atherosclerosis than are cigarette smoking and hypertension.

The effect of serum lipids and lipoproteins on extracranial carotid artery atherosclerosis (CAS) was studied in patients who underwent carotid arteriography. Serum lipid and lipoprotein values along with data on other potential predictors of extracranial CAS were determined in 240 patients who had at least one extracranial carotid artery visualized. In a multiple logistic regression analysis, the independently significant predictors of the presence of extracranial CAS were, in decreasing order of significance, duration of smoking of cigarettes, hypertension, age, and low-density lipoprotein cholesterol. Serum cholesterol, triglycerides, high-density lipoprotein cholesterol, and apolipoprotein A-I did not show an independent effect. Although low-density lipoprotein cholesterol was an independent predictor of the presence of extracranial CAS, its effect as a predictor was far outweighed by the effects of the duration of smoking of cigarettes and a history of hypertension.

Adult↗