Using remotely sensed data to identify areas at risk for hantavirus pulmonary syndrome.

The 1993 U.S. hantavirus pulmonary syndrome (HPS) outbreak was attributed to environmental conditions and increased rodent populations caused by unusual weather in 1991- 92. In a case-control study to test this hypothesis, we estimated precipitation at 28 HPS and 170 control sites during the springs of 1992 and 1993 and compared it with precipitation during the previous 6 years by using rainfall patterns at 196 weather stations. We also used elevation data and Landsat Thematic Mapper satellite imagery collected the year before the outbreak to estimate HPS risk by logistic regression analysis. Rainfall at case sites was not higher during 1992-93 than in previous years. However, elevation, as well as satellite data, showed association between environmental conditions and HPS risk the following year. Repeated analysis using satellite imagery from 1995 showed substantial decrease in medium- to high-risk areas. Only one case of HPS was identified in 1996.

General internists influence students to choose primary care careers: the power of role modeling.

PURPOSE: To determine whether medical students supervised by general internist attendings during the third-year medicine clerkship are more likely to choose primary care careers than students supervised by subspecialist attendings. METHODS: One hundred forty-four consecutive medical students rotating on the general medicine inpatient service during the 1993-1994 academic year were surveyed about their career choice and professional expectations, both at the beginning and end of the clerkship; an additional 50 students completed a post-clerkship survey only. The cohort of students was surveyed at graduation to determine stability of their career preferences. RESULTS: Both pre- and post-clerkship surveys were completed by 138 of 144 students (96%); post-clerkship surveys were completed by 181/194 (93%); and graduation surveys were completed by 137/188 (73%). Fifty-eight students (32%) designated primary care (general internal medicine, general pediatrics, or family practice) as their career choice post-clerkship; of these, 45 students (78%) also indicated a primary care career choice at graduation. Characteristics associated with choosing primary care post-clerkship were: low income expectation, desire to interact closely with patients, desire to contribute to society, low class rank, female gender, and high educational debt. Having a physician parent was negatively associated with choosing primary care. After controlling for important demographic, academic and attitudinal characteristics, increasing exposure to a general internist attending was associated with choosing primary care (OR = 5.1, comparing highest to lowest amount). Among students choosing primary care, exposure to a general internist attending was associated with choosing general internal medicine in a dose-dependent fashion (OR = 4.2, comparing highest to lowest amount). CONCLUSIONS: Although career choice is clearly related to personal characteristics such as socioeconomic background and humanistic qualities, a high degree of exposure to general internists during the medicine clerkship is associated with choosing primary care. Exposure of students interested in primary care to general internist attendings may also influence them to consider general internal medicine over family practice and pediatrics.

Medical student career choice: do physical diagnosis preceptors influence decisions?

The authors attempted to measure the influence of a physical diagnosis course and its preceptors on the career decisions of second-year medical students. They designed pre- and post-course questionnaires for 204 second-year medical students in a University of Texas Health Science Center at San Antonio Advanced Physical Diagnosis course. They found that 48% of students changed their career choice during the study period, 75% believed their preceptor was a very good role model, and 39% thought their preceptor influenced their career choice. Students who believed their preceptor was a good role model were 31 times more likely to consider their preceptors' career (confidence interval [CI] 95, 4.1-236). In results from students precepted by primary care physicians, there was a nonsignificant trend toward choosing a primary care career (Odds Ratio [OR]) 1.6 [CI95, 0.7-3.3]). Factors associated with a final career choice of primary care were a primary care career choice at baseline (OR 8.5 [CI95, 3.8-19.0]) and a belief that physical diagnosis skills would be important to a future career (OR 4.7 [CI95, 1.1-20.0]). By multivariable analysis, only a primary care career choice at baseline remained significant (OR 8.7 [CI95, 3.5-21.3]). The authors concluded that good role models can influence students to consider alternative career choices, but this effect is still overshadowed by a student's baseline career choice.(ABSTRACT TRUNCATED AT 250 WORDS)

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.

Assessment and treatment of impotence.

Impotence is a common problem. History is primarily relied on to diagnose psychogenic impotence. Sex therapy is an effective treatment. Antihypertensive and psychiatric medicines often cause impotence, but most medicines should be considered a cause if this is supported by the history. Hormonal causes should be suspected in a patient with decreased libido or decreased testicular size, and testosterone should be measured in these cases. Hormone replacement may restore sexual function in hypogonadal men. Doppler sonogram or arteriography should be used to diagnose vascular impotence for men who would be good surgical candidates. Only young men without other illness are considered. There is little need to test neurologic function because there is no specific treatment for neurogenic impotence. These patients and patients who do not respond to the aforementioned treatments should be offered the vacuum erection device, penile self-injection therapy, or penile prosthesis. Choice depends on comorbid illness as well as patient preference. A basic algorithm for the evaluation and treatment of impotence is given in Figure 2.

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.

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.

Detection of injury-prone behaviors among internal medicine patients.

OBJECTIVES: 1) To describe the prevalence of eight injury-prone behaviors (IPBs) and the associations of these behaviors with ten standard chronic disease and sociodemographic risk factors (CDSRFs) among internal medicine patients and 2) to identify a subset of patients with multiple IPBs who might be at particularly high risk of injury. DESIGN: Cross-sectional survey. SETTING: The University of Colorado Health Sciences Center general internal medicine clinic. PATIENTS: Four hundred ninety-two consecutive continuity care patients were eligible. The response rate was 94.3% (464/492). INSTRUMENT: A validated, self-administered questionnaire. MAIN RESULTS: Thirty-four percent of patients did not wear safety belts regularly and 32% had no smoke detector in their homes. Nearly 26% of patients had firearms at home and 6% had a loaded and unlocked gun at home. Fourteen percent of patients had seriously thought about suicide and 6% had attempted suicide. In the prior month, 10% had ridden with a drunk driver, and 4% had driven after drinking too much. Of patients aged 65 years or older, 50% had had recent falls. After adjustment for other CDSRFs, problem drinking was the CDSRF most frequently associated with IPBs. Among men, problem drinking was significantly associated with drinking and driving (OR = 35.3), safety belt non-use (OR = 4.3), and previous thoughts of or attempts at suicide (OR = 6.2). Among women, problem drinking was significantly associated with drinking and driving (OR = 8.7). Among men, being unmarried was the demographic risk factor associated with the most IPBs. Of all IPBs, safety belt non-use was most frequently associated with CDSRFs (ORs ranged from 2.8 to 4.4). Men with three or more IPBs were more likely to be problem drinkers (OR = 9.6), smokers (OR = 15.8), obese (OR = 6.3), and unmarried (OR = 67.1). CONCLUSIONS: 1) Injury-prone behaviors are common among patients attending a university-based internal medicine clinic; 2) men and women have substantially different patterns of risk factor associations; 3) CDSRFs, such as problem drinking smoking, and being unmarried, are associated with many IPBs; 4) safety belt non-use is the IPB associated with the most CDSRFs; and 5) CDSRFs appear to cluster in men with multiple IPBs, suggesting that screening for high-risk individuals may be feasible in clinical practice.