Search PubMedSearch

Biomedical subjects

J F Steiner

Publications and source records attributed to J F Steiner.

At least 19 recordsLinked to original sources

Exercise training improves functional status in patients with peripheral arterial disease.

PURPOSE: In patients with intermittent claudication (IC) a structured walking exercise program improves exercise performance. However, few studies have evaluated the effects of exercise training on functional status during daily activities. We hypothesized that a supervised exercise training program would improve functional status in patients with IC, with 24 weeks of training more beneficial than 12 weeks. A secondary aim was to evaluate the effects of strength training and combinations of strength and treadmill training on functional status. METHODS: Twenty-nine men with disabling IC were randomized to 12 weeks of either supervised treadmill training (3 hr/wk at a work intensity sufficient to produce claudication), strength training (3 hr/wk of resistive training of six muscle groups of each leg), or to a nonexercising control group. Functional status was assessed by questionnaires characterizing walking ability (Walking Impairment Questionnaire, WIQ), habitual physical activity level (Physical Activity Recall, PAR), and physical, social, and role functioning, well-being, and overall health (Medical Outcomes Study SF-20, MOS). Patients alos had their activity levels monitored with an activity monitor (Vitalog). RESULTS: After 12 weeks of treadmill training PAR scores increased by 48 metabolic equivalent hr/wk, the MOS physical functioning score by 24 percentage points, and the number of bouts of walking activity measured by the Vitalog by 4.5 bouts/hr (all p < 0.05). No changes were seen in WIQ scores. After 12 additional weeks of treadmill training improvements initially observed in the PAR, MOS, and Vitalog scores were maintained, and in addition the ability to walk distances (WIQ) improved by 31 percentage points, and the IC severity score had improved by 29 percentage points (both p < 0.05). After 12 weeks of strength training patients improved their WIQ walking speed, stair climbing scores, and MOS well-being scores with no other changes in functional status. Subjects in the control group did not improve functional status by any measure. Twelve weeks of treadmill training after the strength training program maintained WIQ walking speed scores, and activity level defined by Vitalog improved. Twelve weeks of combined treadmill and strength training after the control period had no effect on functional status. CONCLUSIONS: A supervised treadmill training program improved functional status during daily activities, with 24 weeks more effective than 12. In addition, treadmill training alone was more effective in improving functional status in patients with IC than strength training or combinations of the training modalities.

Aged

Safety belt nonuse by internal medicine patients: a missed opportunity in clinical preventive medicine.

BACKGROUND: The United States Preventive Services Task Force recommends that physicians routinely counsel all patients to wear safety belts. We undertook this study to determine the prevalence of the nonuse of safety belts among internal medicine patients, to measure the association of nonuse with other health risk factors, and to ascertain the safety belt counseling practices of physicians. PATIENTS AND METHODS: A total of 492 consecutive patients attending a university-based general medicine clinic were given a validated, self-administered questionnaire, and 94% responded. A medical chart review was performed in a blinded fashion on 94% of the eligible charts. RESULTS: Of the 454 patients who provided safety belt information, 243 (54%) did not wear safety belts. Nonusers were more likely to be problem drinkers, inactive, obese, and to have a low income (adjusted odds ratios 1.8 to 2.0). Of patients with all four of these characteristics, 91% did not use safety belts. The leading reasons for safety belt nonuse were discomfort (35%), short driving distances (24%), and forgetfulness (13%). Obese patients were more likely to report discomfort as their reason for nonuse (odds ratio 2.4; 95% confidence limit 1.4 to 4.3). Eighteen patients (3.9%) reported that a physician had ever counseled them about safety belt use. Only two of 314 medical records (0.6%) noted physician questioning or counseling about safety belt use. CONCLUSIONS: The majority of patients attending an internal medicine clinic do not wear safety belts. Nonusers are more likely to be problem drinkers, inactive, obese, and to have a low income. Patients with multiple health risk factors are at significant risk of nonuse. The most common reason for nonuse is physical discomfort, especially among obese patients. Finally, physicians rarely counsel patients to use safety belts.

Alcoholism

Finding temporal patterns--a set-based approach.

We created an inference engine and query language for expressing temporal patterns in data. The patterns are represented by using temporally-ordered sets of data objects. Patterns are elaborated by reference to new objects inferred from original data, and by interlocking temporal and other relationships among sets of these objects. We found the tools well-suited to define scenarios of events that are evidence of inappropriate use of prescription drugs, using Medicaid administrative data that describe medical events. The tools' usefulness in research might be considerably more general.

Artificial Intelligence

A prospective study of heparin-induced osteoporosis in pregnancy using bone densitometry.

OBJECTIVE: Our purpose was to evaluate the subclinical occurrence of heparin-induced osteoporosis in pregnancy, by means of bone densitometry. STUDY DESIGN: A prospective, consecutive cohort of 14 pregnant women requiring heparin therapy and 14 pregnant controls matched for age, race, and smoking status was identified by 20 weeks' gestation at a university medical center. Proximal femur bone density measurements were taken at baseline, immediately post partum, and 6 months post partum in the cases and controls. Vertebral measurements were also obtained on both groups immediately post partum and 6 months post partum. Bone density as a function of heparin dosing and duration was examined. Nonparametric statistical tests were used for all comparisons. RESULTS: Five of 14 cases (36%) had a > or = 10% decrease from the baseline proximal femur measurements to immediate postpartum values versus none of the 14 matched controls (p = 0.04). Mean proximal femur bone density measurements also decreased in the cases (p = 0.01); this difference continued to be statistically significant 6 months post partum (p = 0.03). No dose-response relationship could be demonstrated. CONCLUSION: Heparin adversely affected bone density in about one third of exposed patients.

Absorptiometry, Photon

The clinical evaluation for diagnosing obstructive airways disease in high-risk patients.

OBJECTIVE: We measured the ability of the medical history, physical examination, and peak flowmeter in diagnosing any degree of obstructive airways disease (OAD). DESIGN: Prospective comparison of historical and physical findings with independently measured spirometry. SETTING: University outpatient clinic. PATIENTS: Ninety-two adult consecutive outpatient volunteers with a self-reported history of smoking, asthma, chronic bronchitis, or emphysema. MEASUREMENTS: All subjects completed a pulmonary history questionnaire and received peak flow (PF) and spirometric testing. The subjects were independently examined for 12 pulmonary physical signs by four internists blinded to all other results. Multivariable analysis was used to create a diagnostic model to predict OAD as diagnosed by spirometry (FEV1 < 80 percent of predicted not secondary to restrictive disease, or FEV1/FVC less than 0.7). RESULTS: The best model diagnosed OAD when any of three variables were present--a history of smoking more than 30 pack-years, diminished breath sounds, or peak flow less than 350 L/min. This model had a sensitivity of 98 percent and specificity of 46 percent. In addition, the model detected all subjects with probable restrictive lung disease. Thirty-one percent of subjects had none of these variables and were at very low (3 percent) risk of OAD. Fifty percent of subjects with one or more abnormal variables had OAD. CONCLUSIONS: The history, physical examination, and peak flowmeter can be used to screen high-risk patients for OAD. Using this diagnostic model, 31 percent of subjects could be classified at very low risk of OAD while half of those referred for spirometry would have abnormal results.

Airway Obstruction

Incidence of digoxin toxicity in outpatients.

The incidence of digoxin toxicity among patients in hospitals has declined in recent years. To evaluate whether a similar decline has occurred in ambulatory care, we reviewed randomly selected medical records for 183 outpatients receiving ongoing treatment with digoxin at 10 urban and rural Department of Veterans Affairs Medical Centers in the Rocky Mountain region. The prevalence of traditional risk factors for digoxin toxicity--elevated serum digoxin and serum creatinine levels, hypokalemia, and a new prescription of an interacting drug-was established from computerized laboratory and pharmacy records. Of the 183 patients, 50 (27.3%) had one or more risk factors for digoxin toxicity: serum digoxin levels were elevated in 13.6% of patients in whom a level was obtained, with hypokalemia in 14.3%, elevated creatinine levels in 17.9%, and possible drug interactions in 5.5% of patients over a 1-year period. Nevertheless, digoxin toxicity occurred in only 2 persons (1.1% or 1.4 per 100 patient-years of treatment). We conclude that digoxin toxicity was rare in this group of outpatients, even in persons presumed to be at high risk because of metabolic abnormalities, increased digoxin concentrations, or the use of interacting drugs. The low rate of digoxin toxicity in outpatients parallels the decline in the incidence of toxicity observed in hospital-based studies.

Aged

The effect of prescription size on acquisition of maintenance medications.

OBJECTIVE: To determine whether large prescriptions (> or = 90 days' supplies) enhance the acquisition of maintenance medications by patients. DESIGN: Study 1: multisite, retrospective cohort study evaluating outpatient digoxin use. Study 2: single-site, retrospective cohort study to confirm Study 1. SETTING: Study 1: Ten Veterans Affairs Medical Centers in the Rocky Mountain region. Study 2: The only facility from Study 1 (site C) that dispensed large prescriptions of maintenance medications. PATIENTS: Randomly selected outpatients receiving two or more digoxin prescriptions (n = 176 in Study 1, n = 114 in Study 2). INTERVENTION: None. RESULTS: The main outcome measure was the proportion of prescribed doses of maintenance medications obtained. In Study 1, patients who received at least one large digoxin prescription obtained a mean of 137.2% of their prescribed digoxin doses over a mean of nine months, compared with 91.3% for patients who received only small prescriptions of < 90 days' supplies (p = 0.02). Patients receiving large prescriptions were more likely to obtain at least 100% of their prescribed amounts of digoxin (adjusted OR = 11.4, 95% CI = 1.3-96.8, p = 0.03). At site C, patients in Study 1 obtained a mean of 129.0% of all maintenance drugs given in large supplies, compared with 95.2% of drugs prescribed only in small supplies (p = 0.006). In Study 2, acquisition of digoxin increased progressively from 89.7% among individuals who received only small digoxin prescriptions to 113.0% for those who received only large supplies (p = 0.002), over a mean of 14 months. CONCLUSIONS: Large prescriptions facilitate the acquisition of maintenance medications but may lead to oversupplies, while small prescriptions impose a barrier to obtaining these drugs.

Aged

Can moderate chronic obstructive pulmonary disease be diagnosed by historical and physical findings alone?

BACKGROUND: The value of the history and physical examination in diagnosing chronic obstructive pulmonary disease (COPD) is uncertain. This study was undertaken to determine the best clinical predictors of COPD and to define the incremental changes in the ability to diagnose COPD that occur when the physical examination findings and then the peak flowmeter results are added to the pulmonary history. SUBJECTS AND METHODS: Ninety-two outpatients with a self-reported history of cigarette smoking or COPD completed a pulmonary history questionnaire and received peak flow and spirometric testing. The subjects were independently examined for 12 physical signs by 4 internists blinded to all other results. Multivariate analyses identified independent predictors of clinically significant, moderate COPD, defined as a forced expiratory volume in 1 second (FEV1) less than 60% of the predicted value or a FEV1/FVC (forced vital capacity) less than 60%. RESULTS: Fifteen subjects (16%) had moderate COPD. Two historical variables from the questionnaire--previous diagnosis of COPD and smoking (70 or more pack-years)--significantly entered a logistic regression model that diagnosed COPD with a sensitivity of 40% and a specificity of 100%. Only the physical sign of diminished breath sounds significantly added to the historical model to yield a mean sensitivity of 67% and a mean specificity of 98%. The peak flow result (best cutoff value was less than 200 L/min) significantly added to the models of only one of the four physicians for a mean final sensitivity of 77% and a specificity of 95%. Subjects with none of the three historical and physical variables had a 3% prevalence of COPD; this prevalence was unchanged by adding the peak flow results. CONCLUSIONS: Diminished breath sounds were the best predictor of moderate COPD. A sequential increase in sensitivity and a minimal decrease in specificity occurred when the quality of breath sounds was added first to the medical history, followed by the peak flow result. The chance of COPD was very unlikely with a normal history and physical examination.

Adult

Finasteride: a 5 alpha-reductase inhibitor.

The pharmacology and pharmacokinetics of finasteride are reviewed, and finasteride's clinical efficacy, adverse effects, and dosage in patients with benign prostatic hyperplasia (BPH) are described. Finasteride is a member of a new class of medications, the azasteroids, that have antiandrogenic activity limited to certain tissues, including the prostate gland. Finasteride inhibits the activity of 5 alpha-reductase, the enzyme necessary for converting testosterone to dihydrotestosterone in the prostate and other tissues. BPH is androgen dependent, and dihydrotestosterone is necessary for the hyperplasia to occur. Finasteride is well absorbed after oral administration; peak plasma concentration is reached in as little as one hour. Finasteride is approximately 90% bound to plasma proteins, is widely distributed, and is extensively metabolized by the liver. In clinical studies, finasteride has been effective in decreasing prostatic volume, increasing urinary flow rate, and decreasing the obstructive and irritative symptoms of BPH. Because of the heterogeneity of BPH, however, treatment is successful in only one third to one half of patients. Finasteride's adverse effects include decreased libido, ejaculatory disorders, and effects on prostate-specific antigen. The recommended dosage of finasteride is 5 mg/day orally. Therapy should be continued for at least six months before the clinical response is evaluated. Finasteride provides a pharmacologic alternative to surgery in patients with BPH.

5-alpha Reductase Inhibitors

Appropriate reductions in compliance among well-controlled hypertensive patients.

Physicians have traditionally viewed partial compliance with medications as a concern only in hypertensive patients whose blood pressure (BP) is poorly controlled. However, partial compliance also occurs in patients whose BP has become normal on medications; in them, reduced compliance may indicate that they have been prescribed more medication than they need. During enrollment for a study of medication reduction in hypertensive patients, we identified 118 male veterans who were eligible for the study because their diastolic BP had been less than 95 mmHg for more than 6 months. Fifty-nine of these patients (50.0%) agreed to participate in the study, of whom 71% successfully reduced or stopped ("stepped down") one or more of their antihypertensive drugs over a 1-year period. The 59 patients who did not enroll continued to receive routine care for hypertension in the clinic without intensive efforts at stepdown. Nevertheless, 24% of these patients reduced or stopped at least one medication over the same time period. In the year prior to the study, 29 of the 118 eligible patients (24.6%) had obtained less than 80% of their medications, measured by pharmacy refill records. Compliance in obtaining antihypertensive medications prior to the study was lower among eligible patients who stepped down medications during the study year (90.4% +/- 18.7%) than in those who did not (102.1% +/- 26.1%, p = 0.006). After adjustment for other predictors of stepdown (number of medications, duration of clinic enrollment, and pre-reduction systolic BP), each 10% increase in compliance among all eligible patients was associated with a reduction in the odds ratio for successful stepdown of 0.8 (95% CI 0.5-1.0, p = 0.01). We conclude that many well-controlled hypertensives appropriately obtain less medications than they are prescribed. Such patients should be considered for reduction of antihypertensive drugs.

Aged

Emergency resuscitation in children. The role of intraosseous infusion.

Intraosseous infusion is a temporary procedure for use in pediatric emergencies when intravenous access is difficult. Multiple drugs and fluids can be safely administered through the intraosseous route. Dosage and rate of infusion are essentially the same as with intravenous infusion.

Child, Preschool

A general method of compliance assessment using centralized pharmacy records. Description and validation.

The prescription refill records of centralized pharmacies are a potential source of information about patient compliance with long-term medications. We developed a method for assessing compliance in such settings and validated our measures using pharmacy data and clinical information from patients with seizure disorders and hypertension. For patients taking the anticonvulsant medication phenytoin, compliance with the drug correlated significantly with mean plasma phenytoin level. For patients on antihypertensive medications, compliance with the treatment regimen correlated with control of diastolic blood pressure. Many patients (15% in the phenytoin validation, and 33% in the blood pressure validation) obtained substantial oversupplies of medications; for these patients, the direct relationship between compliance and drug effect was not evident. A majority of seizure patients with "subtherapeutic" mean plasma phenytoin levels were identified as noncompliant using our measures. We conclude that our method of assessing compliance in obtaining medications is feasible in "managed care" settings, appears to be a valid correlate of drug effects, and may be useful in research and patient care.

Computers

Changing patterns of disease on an inpatient medical service: 1961-1962 to 1981-1982.

To assess changes in disease on an internal medicine teaching service, the records of 292 patients admitted to University Hospital, Denver, Colorado, in the academic years 1961-1962 or 1981-1982 were reviewed. It was hypothesized that patients admitted more recently would be older, more chronically and catastrophically ill, and more likely to have multiple illnesses than patients of an earlier era. Over time, length of stay and mortality rates decreased and acuteness of illness increased, whereas age, chronicity, and co-morbidity remained constant. Changes in the prevalence of some common diseases reflected evolving medical and social influences on hospital use. Modern medical residents are exposed to more patients for a shorter time. They see more acute illness but less of the ongoing process of diagnosis and treatment. Awareness of such changes can help educators design residency programs that better prepare internists for practice.

Acute Disease