Left atrial enlargement in healthy obese: prevalence and relation to left ventricular mass and diastolic function.

BACKGROUND: Left atrial (LA) enlargement has been reported in the obese. However, its prevalence in the healthy obese, clinical correlates and relation to left ventricular (LV) mass and diastolic function have been little investigated. METHODS: Thirty-five consecutive, healthy, normotensive obese (body mass index greater than 28, mean +/- SD 34.2 +/- 2.3 kg/m2) and 35 nonobese subjects (body mass index 24.6 +/- 2.3 kg/m2) comparable in age and sex underwent echocardiographic measurements of LA posteroanterior (parasternal view), mediolateral and superoinferior (apical views) dimensions, aortic root diameter, LV mass and Doppler assessment of LV diastolic function. LA enlargement was defined as a posteroanterior dimension greater than 40 mm. A ratio of LA posteroanterior dimension to aortic root diameter greater than 1.4 was used as an index for disproportionate LA enlargement. RESULTS: LA enlargement was more frequent in the obese than in the nonobese (37% versus 6%, P<0.0001). Similarity, disproportionate LA enlargement was more frequent in the obese (34% versus 6%, P<0.0001). LA posteroanterior dimension correlated well with body mass index (r=0.52, P<0.0001) and LV mass (r=0.56, P<0.0001), and weakly with blood pressure (r=0.28, P<0.02). There was no significant correlation with LV diastolic function, age or sex. In multivariate analysis (multiple r=0.61, P<0.0001), LA posteroanterior dimension correlated significantly only with mass (P<0.005), and the association with body mass index and blood pressure became nonsignificant. Similar results were obtained when LA posteroanterior dimension was replaced with mediolateral or superoinferior dimensions. CONCLUSIONS: LA enlargement is frequent in the normotensive, otherwise healthy obese and correlates well with LV mass. It is not mediated through impairment of LV diastolic function, and likely reflects a physiological adaptation of the heart to the obese state. Further studies are needed to determine whether LA enlargement in the obese is associated with adverse long term outcome.

Are lean smokers at increased risk of lung cancer? The Israel Civil Servant Cancer Study.

BACKGROUND: Whether leanness is related to an increased risk of lung cancer is controversial. OBJECTIVE: To examine the association of leanness with lung cancer incidence in a sample of Israeli men. METHODS: The 23-year lung cancer incidence (1963 through 1986) was determined by linkage to the Israel Cancer Registry in 9975 male civil servants aged 40 through 69 years at initial examination in 1963. In 198,298 person-years of follow-up, 153 cases of lung cancer were identified. In 1963, body mass index (BMI) and cigarette smoking status were determined; in the 1968 reexamination, lung function tests were performed and BMI was reassessed. RESULTS: Adjusted for age, smoking, and city by Cox regression, BMI was exponentially inversely related to lung cancer incidence, with a relative risk of 2.3 (95% confidence interval [CI], 1.4 to 3.8) comparing the lowest fifth of BMI (< 22.93 kg/m2) with the highest. The association was evident in light, moderate, and heavy smokers. Among smokers, the adjusted relative risk was 3.7 (95% CI, 1.9 to 7.3) for the lowest fifth of BMI. The associations were stronger for men in the lowest 10th of the BMI distribution (< 21.38 kg/m2). Controlling for lung function did not materially change the results. The adjusted population-attributable fraction associated with the lowest fifth of BMI among smokers was 20.4% (95% CI, 10.1% to 29.9%). Survival analysis showed that the association of BMI with lung cancer persisted throughout follow-up. CONCLUSIONS: The association shown between thinness and lung cancer incidence, particularly in smokers, was not attributable to the confounding factors studied, preclinical weight loss, or competing risks. Thinness in smokers may lead to, or may reflect, enhanced host susceptibility.

Comparison of clinical and self reported diagnosis for rheumatology outpatients.

OBJECTIVE: To examine the sensitivity of patient self reported diagnoses compared with physician diagnoses in a rheumatology outpatient population. METHODS: A mailed survey to 472 rheumatology outpatients (81% response rate) asked about joint symptoms, disabilities, and underlying rheumatic conditions. The self-reported diagnoses were linked with physician diagnoses in the rheumatology clinic computer based diagnostic registry. RESULT: Overall there was an 87% sensitivity for self reported compared with physician diagnoses when the matching criteria included compatible yet different diagnoses such as rheumatoid arthritis (RA) and osteoarthritis (OA). The sensitivity for exact match was 65%, and it varied with the underlying clinical diagnosis, and was greatest for RA (90%) and ankylosing spondylitis (AS) (100%), and intermediate for OA (52%) and psoriatic arthritis (50%). The sensitivity of self report was primarily related to the type of diagnosis (RA or AS v other rheumatic conditions; odds ratio = 16.3, 95% confidence interval (CI) 9.0 to 29.5), and also to difficulty in activities of daily living (odds ratio = 2.3, 95% CI 1.1 to 4.6) but not age, gender, duration of disease, or clinic attendance, as shown by multivariate analysis. CONCLUSIONS: This study in a rheumatology outpatient population indicated that most patients report a diagnosis which is compatible with the clinical diagnosis. These findings give an upper limit to the sensitivity of self reported diagnoses, though further research is needed to assess the extent to which our results may be generalised to other settings.

The impact of musculoskeletal disorders in the population: are they just aches and pains? Findings from the 1990 Ontario Health Survey.

OBJECTIVE: In light of the high frequency of symptoms of musculoskeletal (MSK) disorders in the population, our objective was to establish the impact of these disorders on morbidity and health care utilization. METHODS: Analysis of interview data from the 1990 Ontario Health Survey (sample size 45,650 from the household population age > or = 16 years) has provided one of the first opportunities to relate reported MSK morbidity to disability, illness duration, and use of health services. RESULTS: Overall, MSK disorders were reported as a cause of morbidity or health care utilization by 29% of the population aged > or = 16 years. The prevalence of chronic MSK disorders was 22%; this includes the 5% of the population who reported longterm disability due to MSK disorders. Of reported MSK disorders, 79% had a duration of over 6 months, and the median duration was 5 years. MSK disorders impact in the previous 2 weeks, defined as reduced activity or use of health care (seeing a health professional or taking prescription or nonprescription medication) specifically because of MSK disorders, was reported by 12% of the population, of whom 72% reported chronic MSK disorders. A health professional had been consulted within the previous year for 72% of the reported MSK disorders. The proportion with consultations was over 80% for durations of one year or less, and remained over 50% for disease durations > or = 10 years. CONCLUSIONS: Reported MSK disorders cannot be dismissed as minor problems not requiring ongoing care in view of their long duration, disabling impact, and continuing consumption of health care services and resources.

Long-term care facility policies on life-sustaining treatments and advance directives in Canada.

OBJECTIVE: To describe the prevalence and content of long-term care facility policies regarding the use of life-sustaining treatments (cardiopulmonary resuscitation (CPR), artificial hydration and nutrition, dialysis, antibiotics for life-threatening infections, transfer to acute care hospital) and advance directives in Canada. DESIGN: Cross-sectional mailed survey. SETTING: Canadian long-term care facilities with 25 beds or more listed in the 1991-92 Directory of Long Term Care Centres in Canada. Institutions listed as, "general hospitals," "psychiatric hospitals," "children's treatment centres," "group homes," or as purely residential facilities were excluded. PARTICIPANTS: Chief Executive Officers or their designates. MAIN OUTCOME MEASURES: Respondents' self-reports regarding the existence of life-sustaining treatment or advance directive policies and content analysis of the policies themselves. RESULTS: Of 1472 long-term care facilities, 1021 (69%) responded. Of these, 344 (34%) institutions had 397 policies regarding the use of life-sustaining treatments or advance directives. Three hundred twenty facilities (31%) had 349 do-not-resuscitate (DNR) policies (40% on CPR alone and 60% on CPR plus other life-sustaining treatments). Seventeen institutions (2%) each had one policy addressing life-sustaining treatments other than CPR, and 31 institutions (3%) each had one policy addressing advance directives. Of the 397 policies, 171 (43%) required routine discussion with all patients, 156 (39%) mentioned futility, 331 (83%) indicated that the competent patient had the right to make a decision about life-sustaining treatment, 265 (67%) indicated that the family of the incompetent patient had this right, 27 policies (7%) mentioned conflict resolution, 378 (95%) had an explicit requirement for recording the decision, 10 (3%) required explicit communication of the decision to the competent patient, 10 (3%) required such communication to the family of the incompetent patient, 260 (66%) required updating of the decision, and 213 (54%) mentioned rescinding or changing the decision. CONCLUSIONS: Only one-third of Canadian long-term care facilities have do-not-resuscitate policies, and even fewer have policies on advance directives or life-sustaining treatments other than CPR. The policies themselves could be improved by encouraging routine advance discussions, scrutinizing the use of the futility standard, stipulating procedures for conflict resolution, and explicitly requiring communication of the decision to competent patients or substitute decision makers of incompetent patients.

Partner notification for sexually transmitted diseases: an overview of the evidence.

OBJECTIVE: To compare the effectiveness of alternative partner notification strategies for gonorrhea, chlamydia, syphilis, HIV and hepatitis B. DATA SOURCES: Studies were identified using MEDLINE, EMBASE, SCISEARCH and other databases, review of reference lists and personal contact with over 80 international experts. STUDY SELECTION: Studies with at least two comparison groups exposed to different partner notification strategies were included. DATA EXTRACTION: Methodological rigor was assessed, and information regarding study populations, interventions and outcomes was extracted independently by two reviewers. MAIN RESULTS: Twelve studies met our inclusion criteria; five were methodologically strong; seven provided data on the referral process; four provided data on trained interviewers compared with routine care providers; and three provided data on the interview process. CONCLUSIONS: Only limited, broad conclusions regarding the effectiveness of various partner notification approaches could be drawn from these comparative studies. Until newer data become available, practice guidelines must be based to a large extent on other grounds.

Partner notification for sexually transmitted diseases: proposed practice guidelines.

Using the results of an analysis of available scientific evidence and a survey of current practice in Canada, as well as expert opinion, these guidelines attempt to consider current partner notification practice in Canada and recommend an approach to determining practice which is flexible enough to address local circumstances. Priority areas for future research were also identified.

A survey of public health partner notification for sexually transmitted diseases in Canada.

OBJECTIVE: To describe the range of practice for sexually transmitted disease (STD) contact tracing/partner notification (PN) by public health agencies in Canada. METHODS: A two-level mailed survey, using two different questionnaires, was conducted from Aug. 1991 to Feb. 1992, directed to: 1) provincial and territorial epidemiologists/directors of STD control, asking about program organization; and 2) 154 local health units/provincially run PN programs, asking about practice patterns of STD partner notification. CONCLUSIONS: In Canada, STD PN by public health agencies is routinely practised in most provinces. PN efforts vary by the STD; less PN effort goes to chlamydia despite a high burden of illness; HIV PN is frequently perceived to be within the responsibility of the physician. For STDs with higher PN effort, the preferred method is provider referral. Targeting is seldom utilized, and there are little available data at a local level monitoring even process measures of effectiveness.

An approach to the development of practice guidelines for community health interventions.

The Community Health Practice Guidelines (CHPG) project was initiated to develop a systematic approach to the critical evaluation of evidence on the effectiveness and efficiency of community health interventions and to the formulation of evidence-based practice recommendations. Three community health interventions--immunization delivery methods, partner notification for sexually transmitted diseases and the combination of restaurant inspection and education of food handlers--were used as prototypes to develop a standardized approach. The CHPG process consists of three components: a review of scientific evidence, a practice survey and formulation of practice guidelines. Imperatives for further development of the CHPG and define research priorities process include creating a coalition of public health organizations to sponsor the process and refining the consensus process so that the practice guidelines accurately reflect both the scientific basis of public health practice and the values of those affected.

Helicobacter pylori infection in children. Is there specific symptomatology?

Helicobacter pylori is an established cause of chronic-active gastritis in both adults and children. However, it is unclear whether H. pylori causes specific clinical symptoms. Therefore, the spectrum of clinical symptoms associated with H. pylori infection was studied in consecutive symptomatic children undergoing diagnostic endoscopy at two pediatric centers, using a structured questionnaire. In Toronto, Canada, 86 of 97 eligible children were enrolled into the study and in Limerick, Ireland, 24 of 29 were enrolled. The frequency of biopsy-confirmed H. pylori infection in Limerick, 16 of 24 (67%), was fivefold higher than in Toronto, 11 of 86 (13%, P = 0.0001). The two study populations were comparable in clinical presentation and duration of symptomatology and did not differ in age (11.9 +/- 3.5 and 11.6 +/- 2.0 years, respectively). Within both study populations H. pylori infection was not associated with specific clinical symptomatology, including duration of abdominal pain, location of pain, and history of melena or vomiting. H. pylori was positively associated with hematemesis in the Limerick group. These findings demonstrate that H. pylori infection in children is not associated with specific clinical symptomatology across varying geographical locations.

Hospital policies on life-sustaining treatments and advance directives in Canada.

OBJECTIVE: To determine the prevalence and content of hospital policies on life-sustaining treatments (cardiopulmonary resuscitation [CPR], mechanical ventilation, dialysis, artificial nutrition and hydration, and antibiotic therapy for life-threatening infections) and advance directives in Canada. DESIGN: Cross-sectional mailed survey. SETTING: Canada. PARTICIPANTS: Chief executive officers or their designates at public general hospitals. MAIN OUTCOME MEASURES: Information regarding the existence of policies on life-sustaining treatments or advance directives and the content of the policies. RESULTS: Questionnaires were completed for 697 (79.2%) of the 880 hospitals surveyed. Of the 697 respondents 362 (51.9%) sent 388 policies; 355 (50.9%) sent do-not-resuscitate (DNR) policies (i.e., policies that addressed CPR alone or in combination with other life-sustaining treatments). Of the 388 policies 327 (84.3%) addressed CPR alone, 28 (7.2%) addressed CPR plus other life-sustaining treatments, 10 (2.6%) addressed advance directives, and the remaining 23 (5.9%) addressed other life-sustaining treatments. Of the 355 DNR policies 1 (0.3%) stated that routine discussion with patients is required, 315 (88.7%) restricted their scope to terminally or hopelessly ill patients, 187 (52.7%) mentioned futility, 29 (8.2%) mentioned conflict resolution, 9 (2.5%) and 13 (3.7%) required explicit communication of the decision to the competent patient or family of the incompetent patient respectively, 110 (31.0%) authorized the family of an incompetent patient to rescind the DNR order, 224 (63.1%) authorized the nursing staff to do so, and 217 (61.1%) authorized physicians to do so. CONCLUSIONS: Although about half of the public general hospitals surveyed had DNR policies few had policies regarding other life-sustaining treatments or advance directives. Existing policies could be improved if hospitals encouraged routine advance discussions, removed the restriction to terminally or hopelessly ill patients, scrutinized the use of the futility standard, stipulated procedures for conflict resolution, explicitly required communication of the decision to competent patients or substitute decision-makers of incompetent patients and scrutinized the provision allowing families and health care professionals to rescind the wishes of now incompetent patients.

Relative importance of musculoskeletal disorders as a cause of chronic health problems, disability, and health care utilization: findings from the 1990 Ontario Health Survey.

OBJECTIVE: Musculoskeletal disorders (MSD) are a leading cause of morbidity in the population, yet their prominence seems to be insufficiently appreciated. We describe the ranking compared with other major body systems of the prevalence of MSD, including arthritis and rheumatism, and back/neck disorders, as a cause of chronic health problems, longterm disability, restricted activity days, consultation with health professionals, and use of both prescription and nonprescription drugs. METHODS: We analyzed data from the 1990 Ontario Health Survey, a stratified random sample of the household dwelling population in Ontario, based on 45,650 individuals aged 16 years and over. RESULTS: MSD ranked first in prevalence as the cause of chronic health problems, longterm disabilities, and consultations with a health professional and ranked 2nd for restricted activity days and use of both prescription and nonprescription drugs. No other body systems ranked invariably within the top 2 ranks for the morbidity indices examined. Even when compared to other major disease groups, arthritis and rheumatism ranked consistently in the top 3 and back/neck disorders also ranked high. MSD were mentioned as a reason for 40% of all chronic conditions, 54% of all longterm disability, 24% of restricted activity days and almost 20% of health care utilization. The impact of MSD was even greater in the 65 and over age group. CONCLUSIONS: MSD have a major role in the health profile of the population. This high burden of illness should be considered in planning health care services and setting research priorities.

Insulin resistance is an important determinant of left ventricular mass in the obese.

BACKGROUND: Obesity in adults is associated with increased left ventricular (LV) mass. The mechanism for this is unclear, however. We tested the hypothesis that insulin resistance is an important independent contributing factor to LV mass in the healthy obese population. METHODS AND RESULTS: The study population consisted of 40 normotensive, nondiabetic, otherwise healthy obese subjects with body mass index (BMI) > 25 kg/m2. LV mass was echocardiographically determined according to the Penn convention, using the formula of Devereux and Reichek. Insulin resistance was assessed using indices derived from Intravenous Glucose Tolerance Test (IVGTT): insulin level at baseline, insulin level at 90 minutes of IVGTT (insulin-90), insulin integration over 90 minutes of IVGTT, and rate of glucose disposal (k value). Insulin-90 (r = .61, P = .0001), k value (r = .55, P = .003), insulin integration over 90 minutes (r = .46, P = .003), basal insulin (r = .44, P = .005), and BMI (r = .59, P = .0001) were all strongly correlated with LV mass by univariate analysis. No significant correlation was found with blood pressure or age. In multivariate regression analysis, only insulin-90 and k value correlated significantly with LV mass (P = .03, P = .02, respectively), accounting for 50% of the variance of LV mass, whereas the association with BMI became insignificant (P = .2). CONCLUSIONS: LV mass in the normotensive nondiabetic obese population is strongly associated with, and may be mediated by, the degree of insulin resistance and its associated hyperinsulinemia, independent of BMI and blood pressure.