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PubMed1999

Randomized controlled trial of the effect of medical audit on AIDS prevention in general practice.

OBJECTIVE: We aimed to evaluate the effect of a medical audit on AIDS prevention in general practice. METHODS: We conducted a prospective randomized controlled study performed as 'lagged intervention'. At the time of comparison, the intervention group had completed 6 months of audit including a primary activity registration, feedback of own data and a meeting with colleagues and experts, and had received brief summaries of the meetings and reminders about the project (a full 'audit circle'). The participants were from general practices in Copenhagen and the Counties of Funen and Vejle, Denmark. One hundred and thirty-three GPs completed the project. The main outcome measures were the number of consultations involving AIDS prevention and the number of talks about AIDS initiated by the GP, and some elements of the content were registered on a chart. RESULTS: No statistically significant difference was observed in the frequency of consultations involving AIDS prevention between the intervention group (1.2% of consultations) and the control group (1.4%). Furthermore, no significant differences were observed regarding the content of these consultations or regarding the fraction of such consultations initiated by the GPs. CONCLUSIONS: Medical audit had no observed effect on AIDS prevention in general practice.

Acquired Immunodeficiency Syndrome↗
PubMed1997

Major haemorrhagic complications during oral anticoagulant therapy in a Danish population-based cohort.

OBJECTIVES: To estimate the incidence of bleeding leading to death or hospital admission in out-patients treated with oral anticoagulants. DESIGN: Population-based historical cohort study 1 January 1992 to 31 September 1994. SETTING: The County of North Jutland, Denmark (488,000 inhabitants). SUBJECTS: Six hundred and eighty-two consecutive patients commencing oral anticoagulant therapy. MAIN OUTCOME MEASURES: Fatal bleeding or bleeding demanding hospital admission. RESULTS: In 756 treatment-years of follow-up, there were 45 major haemorrhagic events (6.0 per 100 treatment-years) in 42 patients, of which seven (0.9 per 100 treatment-years) were fatal. The risk of a first major haemorrhagic episode was highest during the first 90 days of treatment compared with duration above one year (incidence rate ratio, IRR, 1.9; 95% CI, 0.8-4.1). The rate was highest above the age of 60 years, 6.8 per 100 treatment-years, compared with 2.9 per 100 treatment-years below 60 years (IRR 2.3; 95% CI, 1.0-5.6). The rate for a bleeding event was slightly higher in females than in males (IRR 1.3; 95% CI, 0.7-2.3), but did not vary according to type of anticoagulant drug. CONCLUSIONS: The reported rates of major bleeding in this routine community setting implied a higher bleeding risk than was found in randomized trials or when patients are monitored in specialist anticoagulation clinics.

Adult↗
PubMed1999

Mortality cancer risk in parkinsonian patients: a population-based study.

Cancer mortality in a population-based cohort of 10,322 parkinsonian patients (448 deaths observed during 1987 to 1994) was compared with that of the Italian province of Rome using the standardized mortality ratio (SMR). The overall cancer mortality risk was lower in this cohort than in the reference population (SMR, 56; 95% CI, 51 to 61). This reduction included most cancer sites as well as both smoking-related (SMR, 51; 95% CI, 42 to 60) and nonsmoking-related cancers (SMR, 58; 95% CI, 52 to 65). The observed reduction in cancer mortality risk in this cohort cannot be explained entirely by the hypothesis that smokers are less likely to develop PD.

Adult↗
PubMedDate not supplied

ATSDR's trichloroethylene subregistry methods and results: 1989-2000.

The National Exposure Registry of the Agency for Toxic Substances and Disease Registry (ATSDR) uses standard methods to study human exposure in four chemical subregistries: trichloroethylene (TCE), dioxin, benzene, and trichloroethane. The TCE Subregistry includes a baseline cohort of 4006 white registrants with drinking water exposure in Michigan, Indiana, Illinois, Pennsylvania, and Arizona. Between 3 and 6 follow-ups per site were conducted from 1989 to 2000, after baseline. Standardized morbidity ratios, controlling for age and sex, compared prevalences of 16 general health conditions in the subregistry with aggregated national estimates from the 1989-1994 National Health Interview surveys. Excess cases of dermatologic, hematologic, or hepatic disorders and strokes persisted over the lifetime of the registry. Persistent excess urinary tract disorders are likely caused by a systematic bias. This review of first-generation methods may be used to strengthen future exposure registries.

Adolescent↗
PubMedDate not supplied

Hospital utilization of Saskatchewan people with fetal alcohol syndrome.

We describe the hospital utilization of 194 Saskatchewan persons with Fetal Alcohol Syndrome (88% Aboriginal), born between 1973-92. Complete provincial hospitalization data were obtained for 128 patients; partial data for 29 patients. Proportionately more persons missing data were adopted, not living with biological family members or were deceased. The hospital separation rates for the children with FAS, pooled from 1987-91, compared to the 1989-90 Saskatchewan rates were significantly higher (95% level of confidence) for males and females < 1 year, 1-4 years and 5-14 years of age. Relative to Saskatchewan Registered Indians, significantly higher hospitalization rate ratios were observed for males with FAS in all age groups and for females only age 5-14 years. Rate ratios for younger females may not have achieved significance because of missing data. Higher hospitalization rates in children with FAS may not be explained solely by factors associated with ethnicity.

Adolescent↗
PubMed2003

Explaining the excess of rare species in natural species abundance distributions.

The observation that a few species in ecological communities are exceptionally abundant, whereas most are rare, prompted the development of species abundance models. Nevertheless, despite the large literature on the commonness and rarity of species inspired by these pioneering studies, some widespread empirical patterns of species abundance resist easy explanation. Notable among these is the observation that in large assemblages there are more rare species than the log normal model predicts. Here we use a long-term (21-year) data set, from an estuarine fish community, to show how an ecological community can be separated into two components. Core species, which are persistent, abundant and biologically associated with estuarine habitats, are log normally distributed. Occasional species occur infrequently in the record, are typically low in abundance and have different habitat requirements; they follow a log series distribution. These distributions are overlaid, producing the negative skew that characterizes real data sets.

Animals↗
PubMed1993

Descriptive epidemiology of idiopathic dilated cardiomyopathy in Washington County, Maryland, 1975-1991.

Estimates of the incidence of idiopathic dilated cardiomyopathy (IDC) were obtained by identifying cases from Washington County, Maryland who were hospitalized at local and regional hospitals over a recent 17 year period. All of the verified cases had evidence of ventricular dilatation and hypokinesis, with a left ventricular ejection fraction of less than 40%. A total of 26 cases were hospitalized over the period 1975-1991. The average age of the cases at the time of diagnosis was 55.5 years (range 22-80 years of age). About 58% of the subjects were males. A marked increase in newly diagnosed cases of IDC occurred in this population in recent years; 38% of the cases (10 of 26) were newly diagnosed during 1991 alone. Over the period 1975-1991, the average annual incidence rate of hospitalized cases was 1.6 per 100,000 among men and 1.2 per 100,000 among women. During the last 7 years of the case ascertainment period (1985-1991), the average annual incidence rate was 3.5 per 100,000 among men and 2.5 per 100,000 among women. These results provide additional evidence that IDC is being increasingly recognized by clinicians, and underscore the need for an improved understanding of the distribution and determinants of this often fatal condition.

Adult↗
PubMed1997

Cancer following breast reduction surgery in Denmark.

Intuitively, breast tissue mass should be directly related to a woman's risk of breast cancer, simply because having more cells at risk would seem to increase the potential for malignant transformation. However, studies attempting to link breast size with breast cancer risk have been inconsistent. Limitations include crude measures of breast size, the inability to distinguish glandular from adipose tissue, and the confounding influence of co-factors such as obesity. A nationwide study in Denmark was undertaken to investigate the effect of breast reduction surgery on the subsequent risk of breast cancer, including an evaluation of the patterns of risk by age and time since surgery. The Danish Hospital Discharge Registry was used to identify women who underwent reduction mammaplasty between 1977 and 1992. Linkage based on personal identification numbers with the Danish Cancer Registry provided information on cancer incidence. Expected numbers of cancers were calculated from rates in the general population. Among 7,720 women whose breasts were surgically reduced, 182 cancers were subsequently observed cf 209 expected (standardized incidence ratio [SIR] = 0.9;95 percent confidence interval [CI] = 0.7-1.0). Breast cancer was significantly reduced by nearly 50 percent (29 observed cf 53.9 expected, SIR = 0.5, CI = 0.4-0.8), and accounted for the overall deficit in cancer. The risk reductions were related inversely to age at surgery, with significant deficits apparent only among women 40 years of age and older at surgery and especially among those over age 50 (SIR = 0.3). No clear trend was apparent with increasing years post-surgery. The findings indicate that breast reduction surgery among women over age 40 is associated with a lower subsequent risk of breast cancer, but the surgery and presumably glandular mass appear less closely related to breast cancer risk among younger women.

Adolescent↗
PubMed2001

Per capita alcohol consumption and liver cirrhosis mortality in 14 European countries.

AIM: To estimate the effects of changes in per capita alcohol consumption on liver cirrhosis mortality rates in various demographic groups across 14 western European countries. METHOD: Yearly changes in gender- and age-specific mortality rates from 1950 to 1995 were analysed in relation to corresponding yearly changes in per capita alcohol consumption, employing the Box-Jenkins technique for time series analysis. Country-specific estimates were pooled into three regions: northern, central and southern Europe. MEASUREMENTS: Cirrhosis mortality data for 5-year age groups were converted into gender-specific mortality rates in the age groups 15+, 15-44, 45-64 and 65+ and expressed as the number of deaths per 100,000 inhabitants. Alcohol sales were used to measure aggregate consumption, which were calculated into consumption (litres 100% alcohol) per year per inhabitant over 14 years of age and weighted with a 10-year distributed lag model. FINDINGS: The country-specific analyses demonstrated a positive and statistically significant effect of changes in per capita consumption on changes in cirrhosis mortality in 13 countries for males and in nine countries for females. The strongest alcohol effect was found in northern Europe, due mainly to a large effect in Sweden. Moreover, when different age groups were analysed significant estimates were obtained in 29 of 42 cases for males and in 20 of 42 cases for females. Most of the non-significant estimates were found in older age groups. CONCLUSIONS: The results suggest clearly that a change in the overall level of drinking as a general rule affect cirrhosis mortality in different drinking cultures as well as among different demographic groups. Moreover, the findings correspond with what is expected from the collectivity theory of drinking cultures.

Adolescent↗
PubMed2005

Outdoor air pollution, mortality, and hospital admissions from coronary heart disease in Sheffield, UK: a small-area level ecological study.

AIMS: To examine the hypothesis that coronary heart disease mortality and emergency hospital admission rates are higher in areas with higher outdoor air pollution levels. METHODS AND RESULTS: Modelled nitrogen oxides (NO(x)), particulate matter (PM(10)), and carbon monoxide (CO) levels were interpolated to 1030 census enumeration districts using an ecological study design. Results, based on 6857 deaths and 11,407 admissions from 1994-98 and a population of 199,682 aged >or=45 years, were adjusted for age, sex, deprivation, and smoking prevalence. Mortality rate ratios were 1.17 (95% CI 1.06-1.29), 1.08 (95% CI 0.96-1.20), and 1.05 (95% CI 0.95-1.16) in the highest relative to the lowest NO(x), PM(10), and CO quintile categories, respectively. Corresponding admission rate ratios were 1.00 (95% CI 0.90-1.10), 1.01 (95% CI 0.90-1.14), and 0.88 (95% CI 0.79-0.98). CONCLUSION: The results are consistent with an excess risk of coronary heart disease mortality in areas with high outdoor NO(x), a proxy for traffic-related pollution, but residual confounding cannot be ruled out. If causality were assumed, 6% of coronary heart disease deaths would have been attributable to outdoor NO(x,) and targeting pollution reduction measures at high pollution areas would be an option for coronary mortality prevention.

Age Distribution↗
PubMed1996

Incidence of inflammatory bowel disease in Italy: a nationwide population-based study. Gruppo Italiano per lo Studio del Colon e del Retto (GISC)

BACKGROUND: The epidemiology of inflammatory bowel disease (IBD) in Southern Europe is still unclear. Sporadic reports suggest a lower incidence of IBD in Italy than in other Western Countries and the USA. METHODS: A nationwide population-based study was carried out to estimate IBD incidence rates in eight Italian cities. All new cases of IBD diagnosed over 4 years in the target populations were collected from multiple information sources. RESULTS: From 1989 to 1992, 509 ulcerative colitis (UC), 222 Crohn's disease (CD) and 10 undefined IBD cases were collected, giving age-adjusted incidence rates (per 100,000 per year) of 5.2 for UC and 2.3 for CD. Using the capture-recapture method, an estimated completeness of 0.81 was obtained for case archives, without appreciable and significant differences between areas. The rates computed after correcting underestimation were 6.8 for UC and 2.8 for CD. The sex ratio M/F was 1.7 for UC and 1.0 for CD. The highest age-specific incidence rates were between 30 and 39 years for UC and between 20 and 29 years for CD. CONCLUSIONS: The incidence rate of CD in italy is homogeneous between the cities investigated and lower than those reported for other Mediterranean countries. In contrast, the UC incidence rate is within the range of those reported in European studies. A wide variability in the UC rates between the cities was also observed. These results could be related to different environmental factors or the genetic background of the populations, or both.

Adolescent↗
PubMed1994

Hip and distal arm fracture rates in peri- and postmenopausal insulin-treated diabetic females.

OBJECTIVES: Hip and distal arm fractures are associated with osteoporosis in the postmenopausal female. In diabetic patients, bone mass has been found to be reduced leading to the hypothesis that diabetes is a risk factor for osteoporosis. Whether this has any clinical implication has only been sparsely elucidated. DESIGN: A cross-sectional case-control study. SETTING: All insulin-treated diabetic females above the age of 40 years who regularly visited the Steno Memorial Hospital out-patient clinic in 1989. Peri-and postmenopausal females from the general population living in a similar suburban region of Copenhagen admitted to Glostrup University Hospital because of a hip or Colles' fracture between 1 January 1989 and 31 October 1990. SUBJECTS: The study comprised 748 insulin-treated diabetic females. Thirty hip fractures and 82 Colles' fractures were reported after the age of 40 years. Out of 26,564 females from the general population, 622 were admitted to Glostrup hospital because of a hip or Colles' fracture. METHODS/INTERVENTION: Answers based on questionnaires sent to all diabetic females, and the use of hospital files and hospital registers. RESULTS: In diabetic females aged 40-49 years, Colles' fracture rate was 2/1000 years and hip fracture rate 0.43/1000 years. Fracture rate increased with age and, amongst 80-89-year-old diabetic females, the frequency of both fracture rates was 31/1000 years. These rates were slightly lower than the rates in the general female population. The relative risk of Colles' fracture in diabetic females aged 40-49 years was 0.3 +/- 0.2 (95% confidence limits) and that of hip fracture 1.0 +/- 1.1. In diabetic females aged 80-89 years, the risk of Colles' fracture and hip fracture were 1.3 +/- 1.1 and 1.0 +/- 0.9. Fracture rate was not associated with the development of diabetic complications, long-term metabolic control, or age at diagnosis. CONCLUSION: Our results suggest that diabetic osteopenia does not have any clinical impact on fracture risk.

Adult↗
PubMed2004

Geographic correlation between deprivation and risk of meningococcal disease: an ecological study.

BACKGROUND: Meningitis caused by Neisseria meningitidis is a serious infection which is most common in young children and adolescents. This study investigated the relationships between the incidence and age distribution of meningococcal disease, and socioeconomic environment. METHODS: An ecological design was used, including mapping using a Geographical Information System (GIS) at census ward level. RESULTS: Incidence of meningococcal disease was highest in the most deprived wards, with a relative risk of 1.97 (1.55 - 2.51). Mapping revealed geographical coincidence of deprivation and meningococcal disease, particularly in urban areas. Two-thirds of the increased incidence was due to cases in the under fives. CONCLUSIONS: The results suggest that area deprivation is a risk factor for meningococcal disease, and that its effects are seen most in young children.

Adolescent↗
PubMed1991

Electrostatic effects in proteins: comparison of dielectric and charge models.

Two approaches for calculating electrostatic effects in proteins are compared and ana analysis is presented of the dependence of calculated properties on the model used to define the charge distribution. Changes in electrostatic free energy have been calculated using a screened Coulomb potential (SCP) with a distance-dependent effective dielectric permittivity to model bulk solvent effects and a finite difference approach to solve the Poisson-Boltzmann (FDPB) equation. The properties calculated include shifts in dissociation constants of ionizable groups, the effect of annihilating surface charges on the binding of metals, and shifts in redox potentials due to changes in the charge of ionizable groups. In the proteins considered the charged sites are separated by 3.5-12 A. It is shown that for the systems studied in this distance range the SCP yields calculated values which are at least as accurate as those obtained from solution of the FDPB equation. In addition, in the distance range 3-5 A the SCP gives substantially better results than the FDPB equation. Possible sources of this difference between the two methods are discussed. Shifts in binding constants and redox potentials were calculated with several standard charge sets, and the resulting values show a variation of 20-40% between the 'best' and 'worst' cases. From this study it is concluded that in most applications, changes in electrostatic free energies can be calculated economically and reliably using an SCP approach with a single functional form of the screening function.

Bacterial Proteins↗
PubMed1998

Industry-wide study of mortality of pulp and paper mill workers.

A study of pulp and paper mill workers indicated low risks of death from all causes (standardized mortality ratio (SMR) = 0.74) and all cancers (SMR = 0.81) compared with U.S. rates. The leukemia death rate in workers was not higher than the U.S. rate but was higher than the rate in county populations surrounding mills. Workers whose last jobs were in the finishing areas of the mills had an elevated SMR for liver cancer. An internal comparison of occupational characteristics indicated that workers employed in mills using other chemical pulping operations had significantly elevated mortality from all causes, all cancers, heart disease, lymphomas, and brain cancers. Lung cancer mortality was elevated in mills using kraft pulping. The internal comparisons confirmed the association between work in finishing and the risk of liver cancer. This study was designed to investigate whether pulp and paper mill workers have any risks that would indicate the need for studies detailing exposures.

Adult↗
PubMed2003

Neurological diseases and accidental falls of the aged.

OBJECTIVE: To assess the influence of central and peripheral neurological diseases on the incidence of accidental falls of the aged. DESIGN: 1. Case-control study with cross-section at two years and 2. prospective study in a follow-up up to seven years thereafter. SETTING: Sample of a population study including all 589 inhabitants older than 70 years in three rural communities. PARTICIPANTS: 44 subjects with recurrent falls during two years' follow-up and 41 age and sex matched controls. MEASURES: Neurological diseases and evaluation, other diseases, and incidence of falls during the seven years' follow-up after the cross-section. RESULTS: Compared with the controls the fallers had more often multiple vascular lesions of the brain, extrapyramidal symptoms and signs as well as lumbar nerve root lesions. In the follow-up, cerebrovascular disease, especially with multiple lesions and residual signs of pyramidal tract lesion, Parkinson's disease, rigidity and hypokinesia were associated with increases risk of falling. In multivariate analysis signs of pyramidal tract lesion, rigidity and prior falls were predictors of falls. An increase in the incidence of falls was also associated with vascular lesion of the cerebellum, cerebral white matter hypodensity and cortical atrophy visible on CT. CONCLUSIONS: High incidence of falls was associated with chronic central nervous system diseases. Lumbar root lesions were more common among the fallers but did not increase the incidence of falls in the follow-up. Neurological diseases and evaluation, other diseases, and incidence of falls during the seven years' follow-up after the cross-section. Compared with the controls the fallers had more often multiple vascular lesions of the brain, extrapyramidal symptoms and signs as well as lumbar nerve root lesions. In the follow-up, cerebrovascular disease, especially with multiple lesions and residual signs of pyramidal tract lesion, Parkinson's disease, rigidity and hypokinesia were associated with increased risk of falling. In multivariate analysis signs of pyramidal tract lesion, rigidity, and prior falls were predictors of falls. An increase in the incidence of falls was also associated with vascular lesion of the cerebellum, cerebral white matter hypodensity and cortical atrophy visible on CT.

Accidental Falls↗
PubMed1997

Aortic dissection type A versus type B: a different post-surgical death hazard?

OBJECTIVE: Patients with type B aortic dissection differ from patients with type A dissection in age, hypertension prevalence, indications and timing of surgical treatment, yet reported long-term results have been rather similar (see Doroghazi et al. J Am Coll Cardiol 1984;3:1026-1034). METHODS: With the aim of comparing the post-surgical history, we have reviewed our results in 288 dissections, 213 type A and 75 type B, operated consecutively between 1 January 1970 and 31 November 1994. Follow-up was 100% complete. Empirical survival of both groups was interpolated with a fully parametric method and the shape and scale of the hazard function was investigated. RESULTS: Survival was not significantly different between type A and type B. Parametric survival was, respectively, 0.52% (70% C.L.: 0.48-0.55) vs. 0.56% (0.51-0.62) at 5 years, 0.44% (0.40-0.47) vs. 0.28% (0.23-0.25) at 10 years, 0.37% (0.33-0.41) vs. 0.25% (0.19-0.32) at 15 years, and 0.31% (0.26-0.35) vs. 0.24% (0.18-0.31) at 20 years. Following the high perioperative risk phase in type A dissection, the intermediate and late risk remains constant at a rate of 0.0033 events/month (3.9% patient-years (pt.-years)). By contrast, the postoperative course of type B dissection shows an intermediate risk phase between 4 and 10 years with an average linearized risk of 9.3% pt.-years and a peak of 20%. This determined lower survival rates (24 vs. 31% at 20 years, P = NS). CONCLUSIONS: We conclude that patients with type B dissection have a steeper postoperative death hazard as compared to type A dissection patients. Age confounding or late entry do not explain the difference. This could be possibly related to a greater propensity for expansion, higher risk of malperfusion complications or to limitations of our current surgical treatment.

Adult↗