Sudden cardiac death in diabetes mellitus: risk factors in the Rochester diabetic neuropathy study.

OBJECTIVES: To determine risk factors for sudden cardiac death and the role of diabetic autonomic neuropathy (DAN) in the Rochester diabetic neuropathy study (RDNS). METHODS: Associations between diabetic and cardiovascular complications, including DAN, and the risk of sudden cardiac death were studied among 462 diabetic patients (151 type 1) enrolled in the RDNS. Medical records, death certificates, and necropsy reports were assessed for causes of sudden cardiac death. RESULTS: 21 cases of sudden cardiac death were identified over 15 years of follow up. In bivariate analysis of risk covariates, the following were significant: ECG 1 (evolving and previous myocardial infarctions): hazard ratio (HR) = 4.4 (95% confidence interval (CI), 1.6 to 12.1), p = 0.004; ECG 2 (bundle branch block or pacing): HR = 8.6 (2.9 to 25.4), p<0.001; ECG 1 or ECG 2: HR = 4.2 (1.3 to 13.4), p = 0.014; and nephropathy stage: HR = 2.1 (1.3 to 3.4), p = 0.002. Adjusting for ECG 1 or ECG 2, autonomic scores, QTc interval, high density lipoprotein (HDL) cholesterol, 24 hour microalbuminuria, and 24 hour total proteinuria were significant. However, adjusting for nephropathy, none of the autonomic indices, QTc interval, HDL cholesterol, microalbuminuria, or total proteinuria was significant. At necropsy, all patients with sudden cardiac death had coronary artery or myocardial disease. CONCLUSIONS: Sudden cardiac death was correlated with atherosclerotic heart disease and nephropathy, and to a lesser degree with DAN and HDL cholesterol. Although DAN is associated with sudden cardiac death, it is unlikely to be its primary cause.

Variation in clinical preventive services.

CONTEXT: Preventive services are not delivered at optimal rates in primary care settings, and the literature suggests that a systems approach is key to improvement. Studying variation among clinics could help us to understand the extent of system use in practice. PRACTICE PATTERN EXAMINED: The proportion of patients who are up-to-date for preventive services in 44 primary care practices in the Midwest. PREVENTIVE SERVICES EXAMINED: Papanicolaou (Pap) smear, cholesterol testing, mammography, clinical breast examination, blood pressure measurement, influenza and pneumococcal vaccinations, and advice on tobacco use. DATA SOURCE: 6830 patients surveyed after their clinic visit (response rate, 85%). RESULTS: The proportion of patients up-to-date for preventive services varied widely among clinics. For example, up-to-date rates for Pap smear testing ranged from 70% to 93% and 45% to 88% for cholesterol screening. There was little correlation between a clinic's performance on one preventive service (relative to the other 43 clinics) and its performance on others. When correlations between pairs of up-to-date rates within clinics were examined, only 4 of 28 service pairs were positive and statistically significant and only 1 had a correlation coefficient that exceeded 0.5 (for mammography and clinical breast examination). CONCLUSION: There is wide variation in the rates at which various preventive services are performed, both between and within clinics. This variation, which is probably due to a lack of organized prevention systems that cover multiple services, provides a clear target for improvement efforts.

Time trends in the prevalence of atherosclerosis: a population-based autopsy study.

PURPOSE: Mortality from coronary heart disease is declining but little is known about trends in the prevalence of atherosclerosis. Autopsy rates in Olmsted County, Minnesota, are higher than the national average, offering an opportunity to address this matter. In this study, we determined the prevalence of anatomic coronary disease among autopsied Olmsted County residents and examined the generalizability of these findings. SUBJECTS AND METHODS: Reports of the 2,562 autopsies performed between 1979 and 1994 on Olmsted County residents > or =20 years of age were reviewed for the presence of coronary disease. RESULTS: Among autopsied decedents less than 60 years old at death and among coroner's cases, the prevalence of anatomic coronary disease declined with time (P for trend = 0.05); no trend was detected among older persons or noncoroner's cases. By logistic regression analysis, the crude odds ratio ([OR] per 5 years) for the association between time and anatomic coronary disease was 0.94 (95% confidence interval [CI]: 0.86 to 1.03; P = 0.18]. Age, sex, and antemortem diagnosis of heart disease were also strongly related to the presence of disease. After adjustment for sex and antemortem diagnosis of heart disease, the prevalence of anatomic coronary disease decreased more in younger people than in older people (age 40 years: OR 0.43 [95% CI: 0.24 to 0.80]; age 60 years: OR 0.62 [95% CI: 0.45 to 0.87]; age 80 years: OR 0.89 [95% CI: 0.64 to 1.23]). CONCLUSION: The prevalence of anatomic coronary disease at autopsy decreased between 1979 and 1994, particularly among younger people, supporting the notion that the burden of coronary disease has shifted toward the elderly. These results suggest that the decreased incidence of coronary artery disease has contributed to the recent decrease in coronary mortality, particularly among younger people.

Attitudes of Olmsted County, Minnesota, residents about tobacco smoke in restaurants and bars.

OBJECTIVE: To determine the attitudes of Olmsted County, Minnesota, adults about environmental tobacco smoke in restaurants, bars, and nightclubs. SUBJECTS AND METHODS: In this population survey,2014 adults were contacted by random digit dial methods between February 28 and May 5, 2000, and asked to participate in a telephone survey; 1224 (61%) consented. RESULTS: For the 57% (95% confidence interval [CI], 54%-60%) of the study population that reported exposure to environmental tobacco smoke, the most frequently reported sites of exposure were restaurants (44% [95% CI, 41%-48%]), work (21% [95% CI, 18%-24%]), and bars (19% [95% CI, 16%-22%]). Seventy-two percent (95% CI, 69%-74%) of respondents said that they would select a smoke-free restaurant over one where smoking is permitted, and 70% (95% CI, 67%-72%) said that they would select a smoke-free bar over one where smoking is permitted. The majority of respondents said that they would not dine out or visit bars or nightclubs more often or less often if all restaurants, bars, and nightclubs were smoke-free. CONCLUSIONS: Olmsted County residents prefer smoke-free restaurants, bars, and nightclubs.

Number needed to treat: caveat emptor.

Number needed to treat (NNT)-the inverse of the absolute risk reduction resulting from an intervention-was introduced as a yardstick to describe the harm as well as the benefit of therapeutic maneuvers. Analysis using NNT works well when comparing two or more interventions that have their impact over the same period of time in similar populations or patients. Under other conditions, however, analysis based on NNT can produce results that diverge widely from the impact that the interventions can be expected to have on risk of death. This can happen either for entire populations or for an individual when comparing NNTs for interventions which have their effects on different subsets of the population or when comparing interventions which have their effects over different periods of time. We demonstrate how this can occur by comparing the NNTs and effect of intervention on deaths in a population for automatic implantable cardioverter defibrillators (AICDs), heart transplantation, and cholesterol lowering through nutritional intervention with plant stanol ester.

Preventing heart disease and stroke: messages from the United States.

After rising steeply in the United States for the first two-thirds of the century, mortality from cardiovascular disease in the United States has declined sharply in the past 40 years. In addition to advances in the treatment of clinically manifest cardiovascular disease, the decline in deaths from cardiovascular disease results from a decline in tobacco consumption, decreased serum cholesterol levels, and improved control of hypertension. However, recent changes in risk factor levels are a cause for concern. These changes include sharp increases in smoking among young adults; increases in obesity and type II diabetes; a decrease in physical activity; and, a decline in hypertension control. In order to reduce the burden of cardiovascular disease in Olmsted County, Minnesota, we organized CardioVision 2020 (www.cardiovision2020.org). CardioVision 2020 is a population-based, multi-faceted, collaborative project based on personal commitment and community action.

The ability of a computer program based on the Marquette Matrix-12 short measurement matrix to replicate coding by the Minnesota ECG coding laboratory.

The study was undertaken to determine whether a computer program that uses "short measurement matrix" data from the Marquette Matrix-12 system can replicate Minnesota electrocardiogram (ECG) coding laboratory interpretations. An agreement was found between coding of median complex ECGs at the Minnesota ECG coding laboratory and coding based on Marquette Matrix-12 short measurement matrix. The comparison was based on 763 ECGs plus chest pain history and serum enzyme values for a stratified random sample of 141 patients hospitalized in 1990 or 1991 for an event coded as HICDA 410.x (acute myocardial infarction), 411 (other acute and subacute forms of ischemic heart disease), 413 (angina pectoris), or 796.9 (other ill defined and unknown causes of morbidity and mortality). The population was reconstructed from the stratified random sample to enable population-based inferences. Exact agreement between Matrix-12 and Minnesota coding laboratory interpretation on 4 ECG patterns (evolving diagnostic, diagnostic, equivocal, or other ECG pattern) was 74.5% (Kappa = 0.63 +/- 0.05) for the stratified random sample and 78.8% (Kappa = 0.66 +/- 0.05) for the reconstructed population. For coding myocardial infarction based on the ECG, serum enzyme levels, and ischemic chest pain, agreement was 91.5% (Kappa = 0.85 +/- 0.04) for the stratified random sample and 90% (Kappa = 0.83 +/- 0.04) for the reconstructed population. Although ECG interpretation by a computer program based on the short measurement matrix of the Matrix 12 system results in better agreement than prior attempts to replicate the Minnesota coding laboratory, interpretation remains unacceptably discordant.

The CardioVision 2020 baseline community report card.

OBJECTIVE: To establish baseline data for the CardioVision 2020 program, a collaborative project in Olmsted County, Minnesota, organized to reduce cardiovascular disease rates by altering 5 health-related items: (1) eliminating tobacco use and exposure, (2) improving nutrition, (3) increasing physical activity, (4) lowering serum cholesterol level, and (5) controlling blood pressure. SUBJECTS AND METHODS: Data about tobacco use, diet, and physical activity were collected by random digit dial interview and follow-up questionnaire from a sample of the population. Blood pressure data were collected from medical records at Mayo Clinic, and serum cholesterol data were derived from the Mayo Clinic laboratory database. Data were stratified into 6 age groups. RESULTS: A total of 624 women and 608 men responded to the questionnaire. Population blood pressure data were available for 1,956 women and 1,084 men. Population serum cholesterol data were available for 17,042 women and 12,511 men. Except for women in the 30- to 39-year-old age group, less than 10% of the population sampled met 4 or 5 goals. Conversely, about 90% of the population met at least 1 goal, and about 80% met 1, 2, or 3 of the goals. CONCLUSION: The data from the Olmsted County population indicate considerable opportunity to reduce this population's burden of cardiovascular disease.

Validation of death certificate diagnosis of out-of-hospital coronary heart disease deaths in Olmsted County, Minnesota.

OBJECTIVE: To evaluate the validity of death certificate diagnosis of out-of-hospital (OOH) coronary heart disease (CHD) and sudden cardiac death (SCD) in Olmsted County, Minnesota, between 1981 and 1994. METHODS: In this review of the medical records, autopsy reports, and coroner's files, OOH deaths with heart disease as the underlying cause of death on the death certificate were classified into CHD (International Classification of Diseases, 9th Revision, Clinical Modification [ICD-9-CM] codes 410-414) and non-CHD (other ICD-9-CM heart disease codes) deaths. A 10% random sample (n = 174) of these death certificates was reviewed by physicians, and published validation criteria were applied to classify these deaths into validated CHD or non-CHD categories. Sudden cardiac death was defined as validated CHD that occurred at an OOH location with less than 24 hours between symptom onset and death. RESULTS: The death certificate definition of OOH CHD death (ICD-9-CM codes 410-414) had high sensitivity and positive predictive value of 91% and 96%, respectively. The specificity and the negative predictive value were slightly lower at 86% and 72%, respectively. The sensitivity of death certificate diagnosis of CHD for validated SCD was 89%, and the positive predictive value was 77%. Using a more restrictive definition of SCD, that is, less than 1 hour between the onset of symptoms and death, the positive predictive value of CHD codes for SCD was lower at 52%. CONCLUSIONS: In Olmsted County, the positive predictive values of death certificate diagnosis for OOH CHD and SCD are high. Relying on death certificate diagnoses results in about 5% underestimation of the true CHD rates, whereas their use as a surrogate for SCD yields a 16% overestimation of the true SCD rates.

Lessons from experienced guideline implementers: attend to many factors and use multiple strategies.

BACKGROUND: Studies of clinical guideline implementation have focused almost entirely on changing individual clinician behavior with single intervention strategies and without much attention to the situational context. The goal of this project was to learn from clinic leaders, seasoned in the guideline implementation process, what contextual variables they viewed as important and whether implementation success could be expected if only a single implementation strategy was used. METHODS: In 1998, 12 people with extensive experience in leading clinical guideline implementation were identified who were thought to have particularly keen insight into the process. They were interviewed to generate variables they considered important, as well as strategies they considered effective when used appropriately. A modified nominal group/Delphi process was then used for rating these variables and strategies, and the reactions of international experts were obtained to add perspective to this information. RESULTS: Eighty-seven variables and 25 strategies were identified, clustering in 6 categories (ranked in order of importance by the panel): organizational capabilities for change, infrastructure for implementation, implementation strategies, medical group characteristics, guideline characteristics, and external environment. All six categories were considered to be important, key, or essential by the experienced implementers, although variables within a medical group that directly affect its ability to undertake planned change were rated as much more important than either guideline characteristics or the external environment. DISCUSSION: Although the opinions of those experienced in the process of guideline implementation are primarily of value for generating hypotheses, panel members believe that implementation efforts focusing on the individual physician with a single strategy are unlikely to be successful. Rather, implementation efforts must use multiple strategies that take account of multiple characteristics of the guideline, practice organization, and external environment.

Clinician satisfaction with a preventive services implementation trial. The IMPROVE project.

OBJECT: To discover how attempts to increase the delivery of preventive services affect clinician satisfaction. METHODS: The IMPROVE project was a randomized clinical trial conducted in 44 clinics in and around Minneapolis-St. Paul, Minnesota. Personnel were trained in continuous quality improvement techniques to organize preventive services delivery systems. Satisfaction with delivery of these services and with the sponsoring organizations was measured before the intervention (Time 1), at the end of the intervention (Time 2), and 1 year post-intervention (Time 3). RESULTS: At no time was the intervention associated with a change in the respondents satisfaction with their places of work or with their job roles. Satisfaction with preventive services delivery increased from Time 1 to Time 3 among intervention-clinic respondents. Satisfaction with the IMPROVE project and the efforts of the two managed care organizations to help the clinics deliver preventive services peaked at Time 2 and declined toward baseline at Time 3. Satisfaction with preventive services delivery tended to increase more in the 13 intervention clinics that implemented a preventive services delivery system than in the nine intervention clinics that did not implement a preventive services delivery system (p = 0.15). CONCLUSIONS: Planned organizational change to create systems for preventive services delivery can be associated with increased clinician satisfaction with the way these services are delivered. However, increased satisfaction with preventive services does not necessarily indicate that service delivery rates have increased.

Busy physicians and preventive services for adults.

OBJECTIVE: To study the relationship between overall productivity and the rates at which primary care physicians, in a fee-for-service setting, deliver or prescribe preventive services to adult patients. PATIENTS AND METHODS: The charts of 452 adult patients treated by 8 family practitioners and 5 internists in a fee-for-service practice setting were randomly selected and abstracted for provision of 10 preventive services over a 27-month period. The percentage of eligible patients screened for each service was correlated with the production of each physician measured in relative value units (RVUs). RESULTS: The correlation coefficient between RVUs and the aggregate of the 10 services was 0.23 (95% confidence interval [CI], -0.36 to 0.70). The individual correlation coefficients between RVUs and 9 of the 10 preventive services ranged from -0.05 to 0.43. For cervical cancer screening, however, the correlation coefficient was -0.72 (95% CI, -0.91 to -0.24). CONCLUSION: With the exception of screening for cervical cancer, the data presented in this study do little to support physicians' common belief that lack of time is the reason they are unable to incorporate prevention strategies into their clinical practice.

Failure of a continuous quality improvement intervention to increase the delivery of preventive services. A randomized trial.

CONTEXT: Although there has been enormous interest in continuous quality improvement (CQI) as a measure to improve health care, this enthusiasm is based largely on its apparent success in business rather than formal evaluations in health care. OBJECTIVE: To determine whether a managed care organization can increase delivery of eight clinical preventive services by using CQI. DESIGN: Primary care clinics were randomly assigned to improve delivery of preventive services with CQI (intervention group) or to provide usual care (control group). INTERVENTION: Through leadership support, training, consulting, and networking, each intervention clinic was assisted to use CQI multidisciplinary teams to develop and implement systems for delivery of preventive services. SETTING: 44 primary care clinics in greater Minneapolis-St. Paul. PATIENTS: Patients 19 years of age and older completed surveys at baseline (n = 6830) and at follow-up (n = 6431). Medical chart audits were completed on 4777 patients at baseline and 4546 patients at follow-up. MAIN OUTCOME MEASURES: The proportion of patients who were up-to-date (according to chart audit) and the proportion of patients who were offered a service if not up-to-date (according to patient report) for 8 preventive services. RESULTS: Compared with the control group, based on the proportion of patients who were up-to-date, use of only one preventive service--pneumococcal vaccine--increased significantly in the intervention group (17.2% absolute increase from baseline to follow-up compared with a 0.3% absolute increase in the control group, P = 0.003). Similarly, based on patient report of being offered a service if not up-to-date, delivery of only one preventive service--cholesterol testing--significantly increased in the intervention group compared with the control group (4.6% increase vs. 0.4% absolute decrease in the control group; P = 0.006). CONCLUSION: In this trial, CQI methods did not result in clinically important increases in preventive service delivery rates.

The ability of trained nurses to detect lumps in a test set of silicone breast models.

BACKGROUND: Screening for breast carcinoma is a Healthy People 2000 objective and physical examination is an important component of the screening process. However, many women do not have access to a high quality breast examination. To help address this problem for Native American women, the authors developed the Nurses Providing Annual Cancer Screening (NPACS) training program, a week-long training session conducted at the nurses' clinical site. The goal of the current study was to demonstrate that, after receiving training, the nurses can detect masses in breast models at acceptably high rates. METHODS: Thirty-four nurses who had completed the NPACS training program performed examinations of a test set of six silicone breast models. True-positive and false-positive rates of lump detection were calculated. RESULTS: The nurses were able to detect more lumps in the simulated breasts than both untrained and trained physicians tested in previous trials using the same methodology. On the average, nurses found 76% of the 18 lumps in the 6 breast models. However, their rate of false-positive detections also was somewhat higher. Although the modal number of false-positive detections for both physicians and nurses was 0, the median number of false-positive detections was 0 for the physicians and 1.0 for the nurses. CONCLUSIONS: In the current study, trained nurses were able to detect masses in breast models at high rates. This observation suggests that widespread training of nurses to perform screening breast examinations might be considered as a response to the breast carcinoma screening needs of adult women.

Trends in heart disease deaths in Olmsted County, Minnesota, 1979-1994.

BACKGROUND: Although age-adjusted heart disease mortality has declined since the 1960s, this decline may not have applied equally to all subgroups. OBJECTIVE: To examine recent trends in heart disease mortality, specifically in women and in the elderly. METHODS: Age- and sex-specific heart disease mortality (International Classification of Diseases, Ninth Edition, Clinical Modification [ICD-9-CM] codes 390-398, 402, 404-429) in Olmsted County, Minnesota, between 1979 and 1994 were studied. RESULTS: The total number of heart disease deaths was 3095; 1578 (51%) occurred in women and 1984 (64%) in persons aged 75 years or older. Most heart disease deaths (77%) were coronary disease deaths (ICD-9-CM codes 410-414). Age-adjusted heart disease mortality rates declined from 123 per 100,000 (95% confidence interval [CI], 102-144/100,000) in 1979 to 81 per 100,000 (95% CI, 67-95/100,000) in 1994. Poisson regression analyses indicated that the trends differed according to sex and age. For women, the relative risk (RR) of heart disease death in 1994 compared with 1979 was 0.69 vs 0.53 for men (P = .06). This equates to a decline in heart disease mortality of 2.5% per year in women or 32% over the period and 4.2% per year in men or 47% over the period. The decline was less pronounced as age increased (P < .001). For 60-year-old women, the RR for 1994 compared with 1979 was 0.59, whereas for 80-year-old women, the RR for 1994 compared with 1979 was 0.76. For men, the RR for 1994 compared with 1979 was 0.60 for 80-year-old men vs 0.46 for 60-year-old men. CONCLUSIONS: Between 1979 and 1994, in Olmsted County, the decline in heart disease mortality was of lesser magnitude in women and in the elderly, emphasizing the importance of age- and sex-specific trends to characterize time patterns in heart disease deaths to target preventive measures.

IMPROVE: bridge over troubled waters.

BACKGROUND: The original collaborative project was described in a 1995 Journal article titled "Competing HMOs Collaborate to Improve Preventive Services." IMPROVE (IMproving PRevention through Organization, Vision, and Empowerment) was a large randomized controlled trial using continuous quality improvement to implement clinical systems to improve the delivery of adult preventive services in primary care settings. The project was funded by the Agency for Health Care Policy and Research and initiated as a collaboration between two health maintenance organizations (HMOs) in the Twin Cities: Health Partners and Blue Plus. METHODOLOGY: Forty-four clinics were recruited for the study. Initially the 22 intervention clinics received the multifaceted intervention of leadership support, training on CQI and prevention systems, and consultation and networking opportunities. Next, the comparison clinics received similar assistance, and other clinics were invited into the collaboration. Ultimately, 57 clinics were involved in the project. Multiple collaborations--among clinics, leaders, and HMOs--developed during the project. STATUS: Despite turmoil in the environment during the project, many benefits have been described, including enhanced leadership, growth of systems thinking, better change management skills, and collaboration of competing organizations. SUMMARY: The IMPROVE collaboration survived and flourished in a very competitive market. It was viewed positively by clinicians, medical clinics, and HMOs, and its benefits have extended into the community.

Agreement and coding reliability of the Minnesota and Mayo electrocardiographic coding systems.

PROBLEM: To determine whether diagnoses of myocardial infarction assigned by a system that uses Marquette 12SL electrocardiographic (ECG) codes with manual over-reading agree with diagnoses assigned by Minnesota ECG codes. STUDIES UNDERTAKEN: Agreement and recode reliability of Minnesota and Mayo coding systems based on 768 ECGs plus chest pain history and serum enzyme values were analyzed for a stratified random sample of 141 patients with an event in 1990 or 1991 coded as HICDA 410.x, 411, 413 or 796.9. The population was reconstructed from the stratified random sample so that population-based inferences could be made from the analysis. RESULTS: For the stratified random sample, exact agreement on 4 categories (evolving diagnostic, diagnostic, equivocal, or other ECG) between Mayo and Minnesota ECG coding was 53.9% (kappa = 0.37 +/- 0.05). Code-recode agreement was higher for Minnesota coding (83.0%; kappa = 0.74 +/- 0.05) compared with Mayo coding (73.8%; kappa = 0.64 +/- 0.05). The same pattern was present for the reconstructed population. For coding myocardial infarction based on the ECG, serum enzyme levels, and the presence or absence of ischemic chest pain, agreement between Mayo and Minnesota coding was 84.4% (kappa = 0.72 +/- 0.05) based on the stratified random sample and 81.7% (kappa = 0.67 +/- 0.06) based on the reconstructed population. For the stratified random sample, reliability of diagnosis of myocardial infarction was 93.6% (kappa = 0.88 +/- 0.04) for the Minnesota system and 94.3% (kappa = 0.90 +/- 0.03) for the Mayo system. CONCLUSION: ECG interpretation by the Mayo and Minnesota coding systems differs significantly, and Mayo ECG coding is less reliable than Minnesota ECG coding. Coding of myocardial infarction on the basis of ECGs, serum enzymes, and ischemic chest pain, however, is equally reliable for both systems.