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PubMed2005

Mortality after low-energy fractures in patients aged at least 45 years old.

BACKGROUND: Fractures sustained in low-energy injuries are recognized as a major public health issue, although, with the exception of proximal femoral fractures, little is known about the subsequent mortality rates. The aim of this study was to compare the survival rates of a population of individuals who sustained 3 types of low-energy fractures with age-matched cohorts from within the same population. METHODS: Between January 1988 and December 1999, data were prospectively gathered from all inpatient and outpatient fracture cases at a single trauma unit. During this time, 18,019 patients sustained low-energy fractures of the proximal femur, proximal humerus, or wrist. Survival analysis using the life table method was performed and hazard ratios calculated for risk of mortality when compared to general population controls within the first year postinjury, between the second and fifth years postinjury, and between the sixth and tenth years postinjury. The effects of various social, physical, and mental health parameters on survival were also analyzed using a Cox proportional hazards model. RESULTS: The patients who sustained proximal femoral fractures were older and significantly more physically and mentally impaired than the patients who sustained wrist fractures. The demographic features of the proximal humeral fracture cohort were intermediate between these 2 groups. The mortality was high in all age groups following proximal femoral and proximal humeral fractures, though the relative risk of death, when compared to age-matched population controls, decreased with increasing age at fracture. The risk of death in these groups was greatest in younger individuals and in the first year postinjury. The wrist fracture population had similar or enhanced survival when compared to age-matched population controls. The mortality after fracture was independently predicted by age at fracture, male gender, and use of walking aids, for all 3 fracture groups (P < 0.05), and additionally by level of social dependence in the proximal femoral fracture group (P < 0.05). LEVEL OF EVIDENCE: level one, prospective cohort study. CONCLUSIONS: There is prolonged risk of premature mortality seen in both proximal femoral and proximal humeral fracture groups in the younger age cohorts, possibly as a result of concomitant medical comorbidities contributing to their premature deaths. Elderly patients sustaining proximal femoral fractures, despite high risk of mortality in the first year after injury, have survival approaching those of the general population in the longer term. Elderly patients who sustain wrist fractures have consistently better survival rates than the general population. This group of patients may be physiologically more robust than their age-matched peers in the general population.

Accidental Falls↗
PubMed2001

Description and mission evaluation of the Hungarian case-control surveillance of congenital abnormalities, 1980-1996.

BACKGROUND: The Hungarian Case-Control Surveillance of Congenital Abnormalities was established in 1980. This article describes how the Hungarian Case-Control Surveillance of Congenital Abnormalities was first organized and is currently maintained. The baseline statistics are provided and potential venues of postmarketing surveillance of drug teratogenicity and other public health tasks and research are proposed. METHODS: Cases with congenital abnormalities and patient controls with Down syndrome were selected from the Hungarian Congenital Abnormality Registry. Population controls without congenital abnormalities were selected from the National Birth Registry on the basis of three matching criteria: sex, week of birth, and district of parent's residence. Three sources of information concerning drug exposures, maternal disorders, and pregnancy complications, among others, were used: (1) prospective and medically recorded data from antenatal care logbooks and discharge summaries; (2) retrospective maternal self-reported data obtained with a structured questionnaire in all the three study groups; and (3) data collected by regional nurse in house visits to nonrespondent cases and patient controls. Twenty-five congenital abnormality groups were evaluated. During the 17-year period of data collection, 22,843 cases, 38,151 population controls, and 834 patient controls were incorporated into the data set, constituting the largest population-based case-control data set of congenital abnormalities to date. RESULTS: Demographic features of pregnant women and informative offspring are presented along with the distribution of 25 main groups of congenital abnormalities. CONCLUSIONS: This system is appropriate for postmarketing the surveillance of drug teratogenicity, for the improvement of congenital abnormality diagnosis, to get informed consent, to have a communication with parents and to provide material for research.

Abnormalities, Drug-Induced↗
PubMed2002

I105V polymorphism and promoter methylation of the GSTP1 gene in prostate adenocarcinoma.

The GSTP1 gene encodes for an enzyme, glutathione S-transferase pi (GSTpi),involved in detoxification of carcinogens. An aminoacid substitution (I105V) in GSTP1 produces a variant enzyme with lower activity and less capability of effective detoxification. This variant GSTP*B allele has been associated with a propensity to develop several neoplasms. Because GSTP1 promoter hypermethylation and inactivation of GSTpi expression is a frequent alteration in prostate carcinoma, we hypothesized that this somatic epigenetic modification could obviate any reduced enzyme activity caused by the germ-line polymorphism. We tested for the GSTP1 genotype in a population of prostate cancer patients, and in a control group composed of patients with benign prostatic hyperplasia (BPH) and healthy blood donors. Tissue samples from the 105 prostate cancer cases (105 adenocarcinomas and 34 prostatic intraepithelial neoplasia lesions), and from 43 BPH patients were tested for GSTP1 hypermethylation by methylation-specific PCR. GSTpi protein expression was assessed by immunohistochemistry. No significant effect on prostate cancer risk was detectable for GSTP1 genotype compared with the control population (odds ratio, 1.02; 95% confidence interval, 0.59-1.75). Moreover, no association was found between this genotype and tumor or BPH methylation status. Patients with unmethylated carcinomas did not disclose significant differences in genotypic distribution compared with the control population. In adenocarcinoma, a strong association (P < 0.00001) between GSTP1 promoter hypermethylation and loss of GSTpi expression was observed; however, this trend was not retained in prostatic intraepithelial neoplasia or BPH lesions. Although the GSTP1 polymorphism is not associated with altered susceptibility to prostate cancer, somatic promoter hypermethylation is an effective, but not the only, cause of decreased GSTpi function.

Adenocarcinoma↗
PubMed2002

Ten-year mortality for patients discharged after hospitalization for chest pain or other symptoms raising suspicion of acute myocardial infarction in relation to hospital discharge diagnosis.

AIM: To describe the 10-year prognosis for patients discharged after hospitalization for chest pain or other symptoms giving an initial suspicion of acute myocardial infarction (AMI) in relation to the final hospital diagnosis and furthermore to compare the outcome amongst these patients with the outcome amongst a sex-, age- and community-matched control population. METHODS: All patients who were hospitalized because of chest pain or other symptoms raising a suspicion of AMI and who were discharged alive from hospital. Patients were divided into three groups according to the final diagnosis: (1) confirmed or possible AMI, (2) confirmed or possible myocardial ischaemia and (3) other aetiology. Information on 10-year mortality was available in 3103 patients. A sex-, age- and community-matched control population (n=3221) was compared with the study population in terms of 10-year mortality. TIME OF SURVEY: 15 February 1986 to 9 November 1987. SETTING: Sahlgrenska University Hospital. RESULTS: Patients with confirmed or possible AMI (n=849) had a significantly higher mortality (59.4%) than patients with confirmed or possible myocardial ischaemia (n=1191) who had a mortality of 49.5% (P < 0.0001). The latter group had a higher mortality than patients with 'other aetiology' (n=1063) of whom 40.6% died (P < 0.0001). When comparing the prognosis for patients with AMI and myocardial ischaemia, there was a significant interaction with sex, with a more marked difference in women than in men. Amongst all patients, the 10-year mortality was 49.1 vs. 37.3% in the control group (P < 0.0001). CONCLUSION: The very long term prognosis was strongly associated with diagnosis amongst patients hospitalized and discharged alive because of chest pain or other symptoms raising suspicion of AMI. The absolute mortality difference between patients who were discharged from hospital with confirmed diagnosis of AMI and those whose symptoms were considered to have other aetiology than AMI or ischaemia was nearly 20%. However, the absolute mortality difference between the patients included in the survey and a control population was only 12%.

Aged↗
PubMed1999

The relative risks of hyperglycaemia, obesity and dyslipidaemia in the relatives of patients with Type II diabetes mellitus.

Type II (non-insulin-dependent) diabetes mellitus has a substantial genetic component; however, its molecular basis remains largely unknown. The mode of inheritance is likely to be polygenic, with penetrance influenced by environmental factors. Although the familial aggregation of Type II diabetes is acknowledged, there is little data concerning the prevalence of diabetes in the relatives of subjects with diabetes in comparison with the general population, and our objective was to address this question in the defined geographic region of Oxfordshire, England. We studied 139 first degree relatives of 90 probands with Type II diabetes who attended routine diabetes clinics in Oxfordshire and documented the fasting plasma glucose, triglyceride and HDL-cholesterol concentrations and BMI of these subjects. The probands were selected without regard to family history of diabetes. The control population data were derived from two large-scale Oxford community studies which documented the prevalences of known and newly diagnosed diabetes. The prevalences of newly diagnosed and known diabetes were calculated for each group. The mean BMI, and concentrations of fasting glucose, triglyceride and HDL-cholesterol were compared and prevalence ratios for obesity (defined as BMI > 30 kg/m2), hyperglycaemia (defined as fasting plasma glucose > or = 6.1 mmol/l), and dyslipidaemia (defined as triglyceride > 2.0 mmol/l, HDL < 1.0 mmol/l) were calculated. There was a fourfold higher prevalence of hyperglycaemia in the first degree relatives of subjects with Type II diabetes compared with the control population: the prevalence ratio after adjustment for age, sex and BMI was 4.32 (95 % confidence interval 2.29-8.17). The relatives had a considerably higher fasting plasma glucose concentration than the control population (5.18+/-0.67 mmol/l (mean +/- 1 SD) vs 4.76+/-1.59 mmol/l, p = 0.0001), and this difference remained statistically significant after adjustment for age, sex and obesity. The relatives were significantly more obese, had higher fasting plasma insulin concentrations and had lower HDL-cholesterol concentrations. In conclusion, there is a strong familial aggregation of hyperglycaemia and obesity in the relatives of subjects with Type II diabetes and these subjects have higher fasting plasma insulin concentrations and lower HDL-cholesterol than the general population. These data indicate the particular relevance of screening the first degree relatives of subjects with Type II diabetes, as intervention strategies which aim to improve the metabolic profile are indicated for a large proportion of these subjects.

Adult↗
PubMed1981

IgE responses to environmental antigens in atopic children.

The levels of IgE antibodies to inhaled and dietary antigens and total serum IgG, IgA, IgM and IgE were studied in two highly selected populations of children who had either severe asthma and no history of eczema, or severe asthma and generalized eczema. These populations were age-matched with a healthy control population. The results showed that the eczematous children had significantly higher levels of IgE antibodies to common environmental antigens than the non-eczematous patients with severe asthma. Both patient groups had significantly higher IgE antigen specific antibody levels than the control population to these antigens. Minor differences in total IgG, IgA and IgM levels were noted between the groups. The variations in total IgE levels between the groups showed the same pattern as for specific IgE antibodies.

Antigens↗
PubMed2000

Venous thromboembolism and oral contraceptive use: a methodological study of diagnostic suspicion and referral bias.

BACKGROUND: In studies of oral contraceptive oral contraceptive use and risk of venous thromboembolism, bias related to heightened diagnostic suspicion and preferential referral of oral contraceptive users has been an issue. The aim of our study was to determine the presence and potential impact of diagnostic suspicion and referral bias. METHODS: We conducted a case/non-case study in 21 regional study centers in Germany and, in parallel, a conventional case-control study using the same cases but randomly selected population controls from the same areas. Women with symptoms compatible with venous thromboembolism were included in the study between 1994 and 1999, and classified as cases or non-cases (first reference group) according to the diagnostic work-up (case/non-case study). A second reference group consisted ofpopulation controls (conventional case-control study as an internal comparison for the case/non-case study): 606 cases, 462 non-cases and 2942 population controls aged 15-49 years. Adjusted unconditional regression analyses were performed. RESULTS: Adjusted odds ratios for venous thromboembolism in oral contraceptive users were systematically higher in the classical case-control study compared to the case/non-case approach (using the same cases) across all subgroup analyses (e.g. for idiopathic cases, the odds ratio was 67% higher in the case-control study: 4.33 (95% confidence interval (CI) 3.27-5.74) versus 2.60 (95% CI 1.75-3.88)). We found a significantly increasing trend of oral contraceptive use in four categories of increasingly sophisticated diagnostic tests that were applied to 1067 women with a suspicion of venous thromboembolism, irrespective of the outcome. Stratified analysis showed the diagnostic level to be a confounder. CONCLUSION: In our population-based study with the possibility of internal comparison, we found clear evidence that diagnostic suspicion and referral bias does play an important role in case-control studies of venous thromboembolism risk among oral contraceptive users. This underlines the importance of making an effort to avoid this bias when designing a new study.

Adolescent↗
PubMed1988

Skin problems in workers using visual display terminals. A study of 201 patients.

201 patients with skin problems caused in their own opinion by working with visual display terminals (VDTs) were referred and examined. 18% claimed that their condition improved overnight and 21% that it did so over the weekend. In 25 patients, the skin problems occurred mainly on the cheek turned towards the VDT. Half the patients had rosacea, but their subjective skin symptoms were generally more severe than those in ordinary cases of rosacea, i.e., severe pain, itching and burning. The rest of the patients mainly had common facial dermatoses such as seborrhoeic eczema, acne vulgaris and atopic dermatitis. The patients' skin types, judged by their response to ultraviolet light, did not differ from those of a control population. 18% had non-specific skin problems, e.g., itching and redness. This latter group of patients most closely resembles those cases previously described amongst VDT-workers. An attempt to correlate skin problems with VDTs' electrostatic field strength was unsuccessful because of difficulties in eliminating it. Of 52 electrostatic shields placed in front of patients' VDTs, 38 were defective and 9 were wrongly earthed. The prevalence of migraine-like headache was 40%, which is much higher than in a control population. There was no great use of cosmetics by the study population. When followed up after an average of 8 months, 2/3 of the patients had fewer skin complaints. The question of whether the prevalence of skin problems in general is higher amongst individuals using VDTs than in a control population is addressed in a current study.

Adult↗
PubMed1992

[Growth, weight and physical proportionality in twins].

The growth, weight and proportionality of twins aged 1-15 years from the South Moravian Region were studied and compared with a control population. The sample of twins was divided in three groups: identical twins, nonidentical like-sexed twins and boys and girls from the unlike-sexed pairs. No reasonable differences between twins A and B were observed, therefore they are not evaluated separately. All the twins were born in years 1973-1987, the total number was 2,226 boys and 2,302 girls. A comparison with a control population revealed a lower mean height as well as weight of identical twins until the age of 15 years. The mean weight of identical twins was lower than that of nonidentical ones. Similar pattern were observed also in height, the statistical significance was found only in boys and only on a 5% level. Twins from unlike-sexed pairs were more like the control population than twins from unidentical like-sexed pairs, however, the differences in height in girls were not statistically significant. The distribution of proportionality values has shown an accumulation near zero--we can conclude that twins are more proportionate than other children of their age (i.e. less obese and less meagre). As expected, the observed intra-pair differences in identical pairs were significantly lower than in nonidentical like-sexed pairs.

Adolescent↗
PubMed1985

Releasable vascular plasminogen activator and thrombotic strokes.

Releasable vascular plasminogen activator was measured in 28 patients (14 males and 14 females) with a history of thrombotic strokes documented by computed tomographic scanning. Levels were compared with those in a control population of 126 healthy subjects with no history of thromboembolic disease. The patient population tended to have higher levels of activator than the control population, 0.53 Committee on Thrombolytic Agents (CTA) units/ml of plasma for patients versus 0.21 CTA units/ml for control subjects; however, there was a wide distribution of values, as reported in all previous populations. Since plasminogen activator levels distribute in a non-Gaussian manner, patient values and control values were stratified into deciles. By this approach, the distribution among the patient was not significantly different from that among the control subjects except in females, who demonstrated skewing to higher deciles (p = 0.019). It is concluded that thrombotic strokes are not associated with low levels of releasable vascular plasminogen activator, and in fact, these patients may present with levels considerably above the mean for normal subjects.

Adolescent↗
PubMed1999

Asymptomatic primary biliary cirrhosis: a study of its natural history and prognosis.

OBJECTIVE: To document the natural history of asymptomatic primary biliary cirrhosis and identify prognostic features that would predict the development of symptomatic disease. METHODS: A retrospective chart review of all patients with abnormal liver biochemical tests and antimitochondrial antibody-positive, liver biopsy-compatible primary biliary cirrhosis who were seen in a single tertiary care center between 1983 and 1994 was performed. Statistical analysis using Cox regression was employed to compare survival of the study population with an age- and gender-matched control population and to identify potential prognostic variables. RESULTS: Ninety-one patients were included. Median age at presentation was 53.2 yr. Ninety percent were female. Median follow up was 61.2 months (range 7-206 months). Thirty-six percent (33 patients) became symptomatic with 11% (10 patients) progressing to death or liver transplant. Median predicted length of survival from onset of disease for the entire cohort was 14 yr. Patient survival was less than that predicted for an age- and gender-matched control population (p < 0.05). Univariate and multivariate analysis on a broad spectrum of clinical, biochemical, and histological features at the time of initial presentation failed to reveal any prognostic variables that would distinguish those who would become symptomatic from those who would remain symptom-free. Specifically, three primary variables of interest (associated autoimmune disorders, hepatomegaly, and histological stage) were not found to predict prognosis. CONCLUSION: Patients who present with asymptomatic primary biliary cirrhosis have a shorter life span than the general population. Presently, there are no prognostic features that identify the patients who will develop progressive disease from those who will remain symptom-free. Therefore, treatment should be offered to all patients.

Adult↗
PubMed2001

Acute health effects common during graffiti removal.

OBJECTIVE: The aim of this study was to identify possible health effects caused by different cleaning agents used in graffiti removal. METHODS: In 38 graffiti removers working 8-h shifts in the Stockholm underground system, the exposure to organic solvents was assessed by active air sampling, biological monitoring, and by interviews and a questionnaire. Health effects were registered, by physical examinations, porta7ble spirometers and self-administered questionnaires. The prevalence of symptoms was compared with 49 controls working at the underground depots, and with 177 population controls. RESULTS: The 8-h time-weighted average exposures (TWA) were low, below 20% of the Swedish permissible exposure limit value (PEL) for all solvents. The short-term exposures occasionally exceeded the Swedish short-term exposure limit values (STEL), especially during work in poorly ventilated spaces, e.g. in elevators. The graffiti removers reported significantly higher prevalence of tiredness and upper airway symptoms compared with the depot controls, and significantly more tiredness, headaches and symptoms affecting airways, eyes and skin than the population controls. Among the graffiti removers, some of the symptoms increased during the working day. On a group basis, the lung function registrations showed normal values. However, seven workers displayed a clear reduction of peak expiratory flow (PEF) over the working shift. CONCLUSIONS: Though their average exposure to organic solvents was low, the graffiti removers reported significantly higher prevalence of unspecific symptoms such as fatigue and headache as well as irritative symptoms from the eyes and respiratory tract, compared with the controls. To prevent adverse health effects it is important to inform the workers about the health risks, and to restrict use of the most hazardous chemicals. Furthermore, it is important to develop good working practices and to encourage the use of personal protective equipment.

Adult↗
PubMed1987

Overpopulation as crisis: redirecting health care services in rural Bangladesh.

This article examines the consequences of a "population-as-crisis" theme on the institutional configuration and resource endowments of health care services in an integrated Ministry of Health and Population Control in Bangladesh. The Ministry's focus on women as child bearers and its emphasis on sterilization supported by incentives has contradictory consequences as women become vulnerable to a limited health service and incentives encourage a focus on meeting sterilization targets. Both undermine people's access to and use of primary health care services. Findings from three studies, undertaken between 1978 and 1983, support the argument that despite international concern with preventive and promotive primary health care, simultaneous support for and emphasis on population control inhibits meeting the goals of a broad-based rural primary health care service.

Bangladesh↗
PubMed2001

Correlated responses to selection for faster development and early reproduction in Drosophila: the evolution of larval traits.

Studies on selection for faster development in Drosophila have typically focused on the trade-offs among development time, adult weight, and adult life span. Relatively less attention has been paid to the evolution of preadult life stages and behaviors in response to such selection. We have earlier reported that four laboratory populations of D. melanogaster selected for faster development and early reproduction, relative to control populations, showed considerably reduced preadult development time and survivorship, dry weight at eclosion, and larval growth rates. Here we study the larval phase of these populations in greater detail. We show here that the reduction in development time after about 50 generations of selection is due to reduced duration of the first and third larval instars and the pupal stage, whereas the duration of the second larval instar has not changed. About 90% of the preadult mortality in the selected populations is due to larval mortality. The third instar larvae, pupae, and freshly eclosed adults of the selected populations weigh significantly less than controls, and this difference appears during the third larval instar. Thereafter, percentage weight loss during the pupal stage does not differ between selected and control populations. The minimum amount of time a larva must feed to subsequently complete development is lower in the selected populations, which also exhibit a syndrome of reduced energy expenditure through reduction in larval feeding rate, larval digging and foraging activity, and pupation height. Comparison of these results with those observed earlier in populations selected for adaptation to larval crowding and faster development under a different protocol from ours reveal differences in the evolved traits that suggest that the responses to selection for faster development are greatly affected by the larval density at which selection acts and on details of the selection pressures acting on the timing of reproduction.

Adaptation, Physiological↗
PubMed1988

Risk factors in renal cell carcinoma. II. Medical history, occupation, multivariate analysis, and conclusions.

Potential risk factors in renal cell carcinoma (RCC) were studied in a case-control study of 315 RCC cases and 313 hospital and 336 population controls. Risk factors included medical history, radiation exposure, predominant lifetime occupation, exposure to high-risk industries, and summary of important risk factors by a linear logistic regression model based on the comparison of RCC cases and controls selected from hospitals and the general population for 33 variables. A significant increase in urologic, cardiovascular, malignant, digestive, and metabolic disease was observed among cases over population controls. Exposure to radiation increased the risk, especially in females. A predominant lifetime occupation as a professional decreased the risk, whereas work as an operative increased the risk significantly. Work in petroleum-related and dry-cleaning industries were associated with elevated risk. Multivariate analysis comparing cases with each of the control groups for males and females identified obesity as the most important risk factor in RCC. Weight control at an early age might help to prevent the occurrence of a significant proportion of this rare but increasing malignant disease.

Carcinoma, Renal Cell↗
PubMed1991

[Color-Doppler study of the velocity profile of the left ventricular outflow tract in normal subjects and in patients with valvular aortic stenosis].

A better understanding of the velocity profiles in the cardiac chambers and great vessels should allow more accurate estimation of cardiac output and valve surface area by Doppler echocardiography. The velocity profile in the left ventricular outflow tract was studied by Colour Doppler in 12 patients with pure valvular aortic stenosis with normal left ventricular function and compared with a control population of 12 normal subjects. The selected recordings were digitised and stocked on a laser optic disc. Measurement of the angle of incidence of the line of colour aliasing with respect to the interventricular septum was performed manually on a colour video display unit. A program of digitised image processing allowed the tracing of the axes of reference defining the angle of incidence measured at peak systole. The average angle of incidence was 40.7 +/- 5.6 degrees in the control population and 56.8 +/- 6.8 degrees in aortic stenosis; therefore, in this condition, the angle was significantly flatter (less acute) (p less than 0.001). The correlation between the angle of incidence and the transvalvular pressure gradient was poor (r = 0.24). These results suggest that: real time ambulatory analysis of isovelocity profiles in the left ventricular outflow tract is possible by using the phenomenon of colour aliasing: the presence of an obstacle to left ventricular ejection tends to flatten the velocity profile, justifying the use of the continuity equation in patients with calcific aortic stenosis but questioning its systematic use in control populations of normal subjects used as a reference.

Adolescent↗
PubMed2000

Impact of the Massachusetts tobacco control programme: population based trend analysis.

OBJECTIVE: To assess the impact of the Massachusetts tobacco control programme, which, since its start in January 1993, has spent over $200m-"the highest per capita expenditure for tobacco control in the world"-funded by an extra tax of 25 cents per pack of cigarettes. DESIGN: Population based trend analysis with comparison group. SUBJECTS: Adult residents of Massachusetts and other US states excluding California. MAIN OUTCOME MEASURES: Per capita consumption of cigarettes as measured by states' sales tax records; prevalence of smoking in adults as measured by several population-based telephone surveys. RESULTS: From 1988 to 1992, decline in per capita consumption of cigarettes in Massachusetts (15%) was similar to that in the comparison states (14%), corresponding to an annual decline of 3-4% for both groups. During 1992-3, consumption continued to decline by 4% in the comparison states but dropped 12% in Massachusetts in response to the tax increase. From 1993 onward, consumption in Massachusetts showed a consistent annual decline of more than 4%, whereas in the comparison states it levelled off, decreasing by less than 1% a year. From 1992, the prevalence of adult smoking in Massachusetts has declined annually by 0.43% (95% confidence interval 0.21% to 0.66%) compared with an increase of 0. 03% (-0.06% to 0.12%) in the comparison states (P<0.001). CONCLUSIONS: These findings show that a strongly implemented, comprehensive tobacco control programme can significantly reduce tobacco use.

Adult↗
PubMed2001

The clinical features of functional dysphonia.

OBJECTIVE: This report aims to study the prevalence of features of laryngeal muscle tension in a population of patients with functional dysphonia (FD) and nondysphonic control subjects. STUDY DESIGN: Prospective control-blinded, cross-sectional study. METHODS: We reported on a prospective control-blinded, cross-sectional study of the prevalence of the six features described by Van Lawrence and the six features incorporated in the Morrison-Rammage classification. A senior laryngologist and senior speech pathologist independently rated sound-free, random-sequence video laryngoscopies of 51 patients with FD and 52 nondysphonic control subjects. Assessments were made of the presence or absence of the 12 laryngoscopic features of laryngeal dysfunction, and an overall rating made of the vocal technique as "normal" or "abnormal." RESULTS: More than 60% of the control population demonstrated 1 or more of the 12 features of hyperfunction. There was no significant difference in the prevalence of the six Van Lawrence features, the six Morrison-Rammage features, or the total number of abnormal features between patients with FD and control subjects. On overall assessment, both assessors noted a high prevalence (50% and 36%, respectively) of abnormal vocal technique in the control population. There was no statistical difference in the total number of abnormal features observed between patients with FD and control subjects. Positive predictive value calculations showed that the presence of a clinical feature, at best, presented a 75% chance of correctly identifying a patient with FD and, at worst, a 50% chance. CONCLUSION: The laryngoscopy features commonly associated with FD are frequently prevalent in the nondysphonic population and fail to distinguish patients with FD from normal subjects.

Adolescent↗