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PubMed2005

Community prevalence of hepatitis B infection and modes of transmission in Tamil Nadu, India.

BACKGROUND AND OBJECTIVE: There have been very few community based studies on prevalence of hepatitis B virus (HBV) infection in India. We undertook this study to determine the prevalence of HBV infection in a southern State of India, Tamil Nadu and to describe the important factors related to transmission of the virus in the community. METHODS: Analysis of stored blood samples from a representative population of Tamil Nadu from an earlier community cluster survey on sexually transmitted diseases (STD) prevalence using proportionate to population size (PPS) technique was done. Serum markers of HBV viz., hapatitis B surface antigen (HBsAg), hepatitis B e antigen (HBe Ag) and antibody to surface antigen (anti-HBs) were performed. RESULTS: 1981 subjects were screened in the study. HBsAg prevalence was 5.7 per cent (CI 4.6- 6.8) with 23.5 per cent (25/106) of these having positive HBe-antigen. Community seroprevalence (HbsAg + anti-HBs) of hepatitis B infection was 27.4 per cent (CI: 25.3-29.5) with the highest prevalence of 32.7 per cent (CI: 30.2-35.2) noted in the 15-20 yr age group. Significant independent association (OR 1.4; P=0.006) was detected with family history of exposure to HBV infection by logistic modeling. Other risk factors noted to have significant association were use of disposable needles during injection (OR 0.5; P=0.02) in men, smoking (OR 3; P=0.04) and use of condom (OR 0.6; P=0.08) in women. INTERPRETATION AND CONCLUSION: This community based study shows a high prevalence of hepatitis B infection in the state of Tamil Nadu with the highest prevalence being in the younger (15-20 yr) age group. High prevalence rate in childhood with e-antigenemia seen in 23.5 per cent of HBsAg positive subjects suggest childhood transmission. Poor injection practices and high-risk sexual behavior were found to be additional risk factors for transmission of the disease in the community.

Adolescent↗

PubMed1989

Short term outcome in babies refused perinatal intensive care.

OBJECTIVE: To compare the mortality in babies refused admission to a regional perinatal centre with that in babies accepted for intensive care in the centre. DESIGN: Retrospective study with group comparison. SETTING: Based at the Royal Maternity Hospital, Belfast, with follow up of patients in all obstetric units in Northern Ireland. PATIENTS: Requests for transfer of 675 babies to the regional perinatal centre (prenatally and postnatally) were made from hospitals in Northern Ireland between January 1984 and December 1986. In all, 343 babies were refused admission to the centre, and complete data were available for 332 of them. These babies were either admitted to other neonatal intensive care units (261 babies) or remained in hospitals with only special care cots (71 babies). MAIN OUTCOME MEASURE: Short term mortality. RESULTS: Seventy of the 332 babies refused admission to the centre died compared with 51 of the 333 who were admitted. Multivariate analysis based on a logistic model showed a non-significant increase in mortality among babies treated in other intensive care units compared with babies treated in the centre (relative odds 1.2; 95% confidence interval 0.7 to 1.9). The increase in mortality in babies who remained in a special care baby unit, however, was significant (3.5; 1.7 to 7.0). This increase was particularly significant in babies born at less than or equal to 32 weeks' gestation and who weighed less than 1500 g (8.4; 2.5 to 28.1). CONCLUSIONS: The results of the study confirm the benefits of neonatal intensive care and its particular value in improving survival in babies of low birth weight. As the babies were refused admission to the regional perinatal centre because intensive care cots were not available this deficiency should be corrected.

Gestational Age↗

PubMed2001

Risk factors for and outcomes of noncatastrophic suspensory apparatus injury in Thoroughbred racehorses.

OBJECTIVE: To evaluate effects of toe grabs, exercise intensity, and distance traveled as risk factors for subclinical to mild suspensory apparatus injury (SMSAI) in Thoroughbred racehorses and to compare incidence of severe musculoskeletal injury (MSI) in horses with and without SMSAI. DESIGN: Nested case-control study. ANIMALS: 219 Thoroughbred racehorses racing or in race training. PROCEDURE: Racehorses were examined weekly for 90 days to determine incidence of suspensory ligament injury and monitor horseshoe characteristics. Every horse's exercise speeds and distances were recorded daily. Conditional logistic regression was used to compare exposure variables between incident case (n = 25) and selected control (125) horses. Survival analysis was used to compare time to MSI for horses with (n = 41) and without (76) SMSAI. RESULTS: The best-fitting logistic model for the data included age (< 5 vs > or = 5 years old), toe grab height the week of injury (none vs very low, low, regular, or Quarter Horse height), and weekly distance the week preceding injury (miles). Although the 95% confidence intervals for all odds ratios included 1, the odds for SMSAI appeared to increase with the presence of a toe grab, higher weekly distance, and age > or = 5 years. Horses that had SMSAI were significantly more likely to have a severe MSI or severe suspensory apparatus injury than were horses that did not. CONCLUSIONS AND CLINICAL RELEVANCE: Results suggest that pre-existing SMSAI is associated with development of severe MSI and severe suspensory apparatus injury. Modifying training intensity and toe grab height for horses with SMSAI may decrease the incidence of severe MSI.

Age Factors↗

PubMed2000

Screening for abdominal aortic aneurysm: lessons from a population-based study.

OBJECTIVES: To test the acceptability of screening and to identify modifiable risk factors for abdominal aortic aneurysm (AAA) in men. DESIGN: A trial of ultrasound screening for AAA in a population-based random sample of men aged 65-83 years, and a cross-sectional case-control comparison of men in the same sample. PARTICIPANTS: 12,203 men who had an ultrasound examination of their abdominal aorta, and completed a questionnaire covering demographic, behavioural and medical factors. MAIN OUTCOME MEASURES: Prevalence of AAA, and independent associations of AAA with demographic, medical and lifestyle factors. RESULTS: Invitations to screening produced a corrected response of 70.5%. The prevalence of AAAs (> 30 mm) rose from 4.8% in men aged 65-69 years to 10.8% in those aged 80-83 years. The overall prevalence of large (> 50 mm) aneurysms was 0.69%. In a multivariate logistic model Mediterranean-born men had a 40% lower risk of AAA (> 30 mm) compared with men born in Australia (odds ratio [OR], 0.6; 95% CI, 0.4-0.8), while ex-smokers had a significantly increased risk of AAA (OR, 2.3; 95% CI, 1.9-2.8), and current smokers had even higher risks. AAA was significantly associated with established coronary and peripheral arterial disease and a waist:hip ratio greater than 0.9; men who regularly undertook vigorous exercise had a lower risk (OR, 0.8; 95% CI, 0.7-1.0). CONCLUSION: Ultrasound screening for AAA is acceptable to men in the likely target population. AAA shares some but not all of the risk factors for occlusive vascular disease, but the scope for primary prevention of AAA in later life is limited.

Aged↗

PubMed2002

Hysterectomy for the massive leiomyomatous uterus.

OBJECTIVE: To determine if the complication rate of abdominal hysterectomy is increased in women with greatly enlarged myomatous uteri. METHODS: Three groups of women undergoing abdominal hysterectomy were analyzed according to uterine size: group 1, 208 women with uteri less than 500 g; group 2, 63 women with uterine weights of 500-999 g; and group 3, 47 women with leiomyomata whose uteri weighed at least 1000 g. Logistic regression was used to compare the groups on the risks of having at least one major complication. Adjusted comparisons on other surgical outcomes were performed using a logistic model (for qualitative variables) or a general linear model (for quantitative variables). RESULTS: The risk of experiencing at least one perioperative complication, including blood loss over 500 mL, perioperative blood transfusion, major organ injury, therapeutic antibiotic use, and hospital readmission, increased significantly with uterine weight (P =.006). Group 3 women were at greater risk of having at least one of these complications than either group 1 or group 2 women, with adjusted odds ratios of 3.42 (95% confidence interval [CI] 1.62, 7.25) and 2.64 (95% CI 1.14, 6.13), respectively. Estimated blood loss with surgery also increased with increasing uterine weight (P <.001). Mean estimated blood losses for the study groups were 555.8 +/- 386.5 mL (group 3), 464.3 +/- 285.2 mL (group 2), and 387.6 +/- 281.4 mL (group 1) (P =.032). CONCLUSION: The complication rate from hysterectomy increases with increasing uterine weight, due mainly to an increased blood loss associated with surgery for larger uteri.

Adult↗

PubMed2003

Age and disability affect dietary intake.

The purpose of the study was to provide information on dietary intake in the InCHIANTI study population, a representative sample (n = 1453) of persons living in two towns of Tuscany (Italy), including a large number of old and very old individuals (79.5% >65 y old). We also investigated whether difficulties in nutrition-related activities were associated with inadequate intake of selected nutrients. The percentage of persons with an inadequate intake of nutrients according to Italian Recommended Nutrients Levels (LARN) was higher in the older age groups. Older persons tended to adapt their diets in response to individual functional difficulties, often leading to monotonous food consumption and, as a consequence, to inadequate nutrient intakes. Multiple logistic models were used to evaluate whether inadequate intake of selected nutrients could be predicted by nutrition-related difficulties. Reporting difficulties in three or more nutrition-related activities (chewing, self-feeding, shopping for basic necessities, carrying a shopping bag, cooking a warm meal, using fingers to grasp or handle) significantly increased the risk of inadequate intake of energy [odds ratio (OR) = 3.8, 95% CI = 1.9-7.8) and vitamin C (OR = 2.2, 95% CI = 1.2-4.2, after adjustment for energy intake). More attention to functional problems in the elderly population and the provision of formal or informal help to those who have difficulty in purchasing, processing and eating food may reduce, at least in part, the percentage of older persons with poor nutrition.

Aged↗

PubMed1999

Self-reported health status of low-income mothers.

PURPOSE: To determine the self-reported health status of low-income mothers before major health and welfare policy reform in the state of Ohio, to compare the health status of this group with the general population age-based norms, and to examine differences in health status among insurance and racial subgroups. Policy makers and others have a need for key health-status information about low-income mothers, a topic for which little empirical data currently exist. DESIGN: Descriptive using a cross-sectional survey with convenience sampling; 502 women were interviewed at intake sites in four countries in central Ohio, 1995 to 1996. METHODS: Health status was measured using the general health status index developed by J. E. Ware and colleagues (1995). Two summary measures, one indicating physical health and one indicating mental health, were used and compared with published norms. Multivariate logistic models were examined for depression and physical health status. FINDINGS: A significant level of depression in the population of low-income mothers was found as were differences in physical health scores by insurance group. People insured privately had the highest physical health scores, while those enrolled in fee-for-service Medicaid had scores indicating the poorest health. No significant difference was found between racial groups in self-reported health status. CONCLUSIONS: Self-reported mental health status is low among some low-income female populations. Physical health is worse for the Medicaid-enrolled group compared to both uninsured and privately insured groups. This poor state of health will likely diminish the success of welfare reform to improve the economic self-sufficiency of these women unless comprehensive health services are available.

Adult↗

PubMed1999

Associations of medical status and physical fitness with periodontal disease.

To determine the possible associations of medical status and physical fitness with periodontal disease, a cross-sectional study was conducted. The subjects were 517 males and 113 females aged 23 to 83 years who participated in a multiphasic health test at the Aichi Prefectural Center of Health Care, Japan, from 1992 to 1997. Their periodontal status was assessed by means of the CPITN scoring system. To assess the strength of associations between the examined factors and the score, odds ratios were computed using ordinal logistic models. Conventional risk factors such as old age, smoking habits, and higher fasting plasma glucose and simplified debris index increased the risk of periodontal disease. Hypertension, hematuria, leucocytosis or thrombocytosis, positive C-reactive protein and higher serum alkaline phosphatase were positively associated with the score, whereas higher serum high-density lipoprotein cholesterol was related to a lower risk. Poor physical fitness affecting aerobic capacity, foot balance and reaction was associated with a higher CPITN score. These associations were independent of the conventional risk factors. Although these new potential risk factors should be further investigated for their causal relationship, our findings suggested a close relationship of oral health to medical status and physical fitness.

Adult↗

PubMed2000

Improved birth outcomes among HIV-infected women with enhanced Medicaid prenatal care.

OBJECTIVES: This study evaluated the impact of enhanced prenatal care on the birth outcomes of HIV-infected women. METHODS: Medicaid claims files linked to vital statistics were analyzed for 1723 HIV-infected women delivering a live-born singleton from January 1993 to October 1995. Prenatal care program visits were indicated by rate codes. Logistic models controlling for demographic, substance use, and health care variables were used to assess the program's effect on preterm birth (less than 37 weeks) and low birthweight (less than 2500 g). RESULTS: Of the women included in the study, 75.3% participated in the prenatal care program. Adjusted program care odds were 0.58 (95% confidence interval [CI] = 0.42, 0.81) for preterm birth and 0.37 (95% CI = 0.24, 0.58) for low-birthweight deliveries in women without a usual source of prenatal care. Women with a usual source had lower odds of low-birthweight deliveries if they had more than 9 program visits. The effect of program participation persisted in sensitivity analyses that adjusted for an unmeasured confounder. CONCLUSIONS: A statewide prenatal care Medicaid program demonstrates significant reductions in the risk of adverse birth outcomes for HIV-infected women.

Adult↗

PubMed2000

Relationship between breast milk feeding and atopic dermatitis in children.

OBJECTIVE: To determine whether or not the breast milk feeding has a role in the prevalence of atopic dermatitis among children. METHODS: The target population of the study was all children participating in health check-up program for 3-year-old children in 60 municipalities locating 10 selected prefectures during designated 2 months between October and December 1997. Using a questionnaire, information on nutrition in infants (breast milk only, bottled milk only, or mixed), parity, mothers' age at birth, and a history of atopic dermatitis was obtained. Besides, data on potential confounding factors were obtained. RESULTS: Questionnaires from 3856 children (81.6% of those who were to participate in the programs, and 96.4% of children who participated them) were analyzed. After the adjustment for all potential confounding factors using unconditional logistic models, the risk of atopic dermatitis was slightly higher among children with breast milk (odds ratio [OR] = 1.16 with 95% confidence interval [CI] 0.96-1.40). Mothers' age at birth (OR for those who were more than 30 years or older in comparison with those who were younger than 30 years = 1.15; 95% CI, 0.96-1.37) and those with second or later parity orders (OR = 1.14, 95% CI; 0.95-1.35) showed odds ratios that were higher than unity without statistical significance. CONCLUSION: Breast milk elevates the risk of atopic dermatitis slightly without statistical significance; the risk may be, however, higher in children in second or later parity orders.

Adult↗

PubMed2005

MnSOD Val-9Ala genotype, pro- and anti-oxidant environmental modifiers, and breast cancer among women on Long Island, New York.

Excessive oxidative stress may induce and promote breast carcinogenesis. Manganese superoxide dismutase (MnSOD) is critical to management of oxidative stress by catalyzing the formation of hydrogen peroxide from two superoxide anions. To examine the relationship between MnSOD Val-9Ala polymorphism, breast cancer and potential modifiers, we analyzed data from a large population-based case-control study. Study participants completed an in-home interviewer-administered questionnaire, and self-completed a Block food frequency questionnaire. Age-adjusted unconditional logistic models included 1034 cases and 1084 controls. As compared with Val/Val genotype, we found no association between MnSOD Ala/Val (OR = 0.98, 95% CI: 0.79-1.21) and Ala/Ala (OR = 1.00, 95% CI: 0.79-1.28) genotypes and breast cancer. Results did not differ by menopausal status, stage of tumor, or estrogen and progesterone receptor status. No discernable patterns of interaction were found between this MnSOD variant and anti-oxidative exposures, including fruit and vegetable intake or NSAID use, or pro-oxidant exposures, including smoking and alcohol. This study provides little evidence that variation in Val-9Ala polymorphism of MnSOD alone or through substantial interaction with key exposures believed to be pro- or anti-oxidant properties influences breast cancer risk.

Aged↗

PubMed2003

Predictors of advanced proximal neoplasia in persons with abnormal screening flexible sigmoidoscopy.

BACKGROUND & AIMS: The relationship between distal and proximal colonic findings is uncertain. Thus, there is no consensus on which findings on screening flexible sigmoidoscopy should trigger colonoscopy. METHODS: We analyzed data from the Prostate, Lung, Colorectal, and Ovarian Cancer Screening Trial to assess the relationship between distal and proximal colonic findings. RESULTS: A total of 8802 subjects had an abnormal baseline sigmoidoscopy and colonoscopy follow-up. Subjects with <10-mm single or multiple tubular adenomas had similar risks for advanced proximal neoplasia as subjects with hyperplastic polyps or other benign lesions (3%-5%). Subjects with large (>or=10 mm), villous, or severely dysplastic distal adenomas had similarly elevated risks for advanced proximal neoplasia (11%-12%). Multivariate logistic modeling showed a significantly increased risk for advanced proximal neoplasia associated with the presence of a large tubular (odds ratio [OR], 2.6; 95% confidence interval [CI], 2.0-3.4) or villous distal adenoma (OR, 2.7; 95% CI, 2.1-3.5) but not with the presence of one (OR, 1.05; 95% CI, 0.8-1.3) or multiple (OR, 0.8; 95% CI, 0.5-1.2) <10-mm tubular distal adenomas. CONCLUSIONS: Among subjects with a polypoid lesion on screening flexible sigmoidoscopy, those with small tubular distal adenomas are at similar risk for advanced proximal neoplasia as those without distal adenomas. Subjects with a large, villous, or dysplastic distal adenoma are at increased risk. A strategy that encourages individuals with small tubular adenomas on sigmoidoscopy to undergo follow-up colonoscopy and excludes those with nonadenomatous lesions is of questionable validity, because both groups are at similar risk for advanced proximal neoplasia.

Adenoma↗

PubMedDate not supplied

[Work-related disabilities and workers' difficulties in rejoining the labor market].

This cross-sectional study was conducted on permanently disabled workers assisted by the Center for Occupational Rehabilitation (CRP) in Belo Horizonte, Minas Gerais, Brazil, to evaluate factors associated with their chances of readmission into the labor market. A logistic model was used to investigate workers' acceptance into the professional rehabilitation program and their return into the market. The most decisive factors for their acceptance were age, presence of repetitive strain injury (RSI), and educational level. The most favorable situation was that of workers with RSI under 40 years of age and with average schooling (75.6%). Results showed that young male workers with high educational levels were the ones with the best chances of rejoining the market (90.9%). A controversial issue relates to workers' acceptance and program results. In order to be accepted, the worker had to display a given age and educational profile. Workers with RSI had this profile, but once accepted they were the ones with the greatest difficulty in rejoining the work force. In addition, discrimination against female workers was observed, despite their characteristics being similar to those of males.

Accidents, Occupational↗

PubMed1999

Health habit counseling amidst competing demands: effects of patient health habits and visit characteristics.

OBJECTIVE: This study assesses the effects of competing demands, such as poor health habits or new medical problems, on health-habit counseling during a primary care visit. METHODS: We surveyed a consecutive sample of 1,259 patients visiting primary care clinicians at an academic VA medical center. Before the visit, patients reported their health status, health habits, and sociodemographics; immediately after the visit, patients reported reasons for the visit and whether they had been counseled about specific health habits. We scored visit acuity ranging from visits for unscheduled walk-in care or new medical problems to scheduled visits for check-ups or old problems. We defined counseling "triggers" as clinical indications for counseling about particular health habits (e.g., smoking). We developed a logistic model predicting primary care provider counseling during a visit. RESULTS: Over two-thirds of patients (68.9%) received some health habit counseling. Controlling for other independent variables, patients with more triggers were more likely to report being counseled. Counseling rates went up as visit acuity went down; patients with the lowest visit acuity having 67% greater odds of being counseled than patients with the highest visit acuity. CONCLUSIONS: Physicians set priorities for health-habit counseling during a visit based on patients' health habit problems or triggers; whether the visit is scheduled or walk-in; and whether the patient has new or acute problems. Future research about primary care performance of health habit counseling should account for these patient and visit characteristics, and prevention-oriented health care organizations should ensure access to scheduled "check-up" visits.

Aged↗

PubMed1998

Bayesian analysis via Gibbs sampling of susceptibility to intramammary infection in Holstein cattle.

A Bayesian analysis was undertaken to assess the susceptibility of Holsteins to mastitis from 120 to 305 d in milk. Data included 595 lactations from 267 cows. The response variable was presence or absence of intramammary infection; explanatory variables were period and season of calving, somatic cell score, and cow. The logistic model adopted had period and season of calving and the regression on somatic cell score with vague prior distributions, and cow effects had a normal prior with unknown variance sigma u2, which, in turn, had a gamma prior. Implementation was by Gibbs sampling. Posterior densities of location parameters were unimodal and symmetric. The probability of intramammary infection of a sample cow was skewed. The posterior distribution of sigma u2 was skewed also. Gibbs samples of sigma u2 had high lag correlations, which gave an effective sample ranging between 47 and 117 from a chain of size 3000. There were differences between estimates of sigma u2 found using Gibbs sampling and those obtained using approximations. The low information content arising from the small size of the data and the binary nature of the response are reasons for such differences. A sensitivity analysis revealed influences of hyperparameters of the prior distribution of sigma u2 on inferences about this parameter.

Animals↗

PubMedDate not supplied

[Evaluation of the diagnosis of pigmented tumors of the skin and factors leading to a decision to excise. Dermatologists of the Postgraduate Association of Haute-Normandie].

INTRODUCTION: The necessity of excising melanomas characterized by a slight thickness at an early stage, leads dermatologists to remove pigmented lesions which do not correspond to melanomas. The aims of this study were: a) to prospectively assess the accuracy of melanoma diagnosis, b) to quantify the number of excisions performed according to the degree of melanoma suspicion, c) to determine the specific clinical sign or signs of relevant diagnostic value. PATIENTS AND METHODS: This study was conducted prospectively from January 1996 to August 1997 by dermatologists in private practice and dermatologists from a University Hospital staff. When it was decided to excise a pigmented lesion, a form was filled out choosing the most appropriate clinical diagnosis, the degree of melanoma suspicion, and clinical signs which lead to surgery. Based on histological findings as the reference, the sensitivity, specificity, accuracy of melanoma diagnosis and the kappa test that evaluates the concordance between clinical and histological diagnosis, were performed. The diagnostic value of clinical signs was assessed by variance analysis. RESULTS: Of the 353 excised lesions, 38 (10.7 p. 100) were identified as melanoma on histologic examination. The sensitivity, the specificity and diagnostic accuracy were: 79 p. 100, 94 p. 100 and 53 p. 100 respectively. The kappa test concordance between clinical and histological diagnosis was 0.66. Two hundred and two lesions (57 p. 100) were excised even though the clinical suspicion of melanoma was poorly considered. Only one of these 202 lesions was identified histologically as a true melanoma. Thirty seven (24.5 p. 100) of the 151 remaining excised lesions with an "average" or "strong" suspicion were true melanomas. The clinical signs considered, alone or associated, had a poor predictive positive value (< 38 p. 100). An analytical approach performed with a logistic model permitted the identification of two associated signs suggesting a best diagnostic value. DISCUSSION: This is the only study, to our knowledge, reported in the literature which prospectively assesses the sensitivity, specificity and concordance between clinical and histological diagnosis of melanoma. Results were considered from average to good. The originality of this study was to assess the number of pigmented lesions excised according to the degree of melanoma suspicion, suggesting the possibility of reducing the number of nevi removed when the melanoma risk was considered clinically poor. Finally, this study emphasizes the limits of clinical semiology and the need for future diagnostic methods in the assessment of melanoma.

Adult↗

PubMed1993

Decline in stroke mortality in North Carolina. Description, predictions, and a possible underlying cause.

Data from the National Center for Health Statistics were used to describe the decline in age-adjusted stroke mortality rates from 1962 to 1987 for North Carolina and for six regions of the state. For the state as a whole, stroke mortality decreased from 0.0050 to 0.0018 (64% decrease) for white males, 0.0039 to 0.0016 (59% decrease) for white females, 0.0072 to 0.0030 (58% decrease) for black males, and 0.0064 to 0.0025 (61% decrease) for black females. Under the hypothesis that the rate of decline in stroke mortality will slow and approach a "floor," a four-parameter logistic model was fit to the data. This model suggests that most of the decline in North Carolina stroke rates had occurred by 1987 and that the rates are now approaching the floor. For example, the estimated 1987 white male stroke mortality rate was 0.00190 and the floor 0.00176, suggesting only a 7% decline in the future. Similar percentage differences between 1987 levels and the floor were estimated for the three other race-gender groups. This analysis also suggested that while the absolute disparity by sex and race decreased between 1962 and 1987, the ratio of black to white mortality rates and the ratio of male to female mortality rates remained relatively constant. Estimates of 1-year case-fatality rates from two surveys of hospitalized stroke patients in a high-mortality five-county region of North Carolina decreased from 51% in 1970 to 38% in 1980. This decrease in stroke fatality rate is sufficient to account for 64% of the decrease in mortality estimated for this region over the same period.

Black People↗

PubMed2006

Radical radiotherapy for invasive bladder cancer: What dose and fractionation schedule to choose?

PURPOSE: To establish the alpha/beta ratio of bladder cancer from different radiotherapy schedules reported in the literature and provide guidelines for the design of new treatment schemes. METHODS AND MATERIALS: Ten external beam radiotherapy (EBRT) and five brachytherapy schedules were selected. The biologically effective dose (BED) of each schedule was calculated. Logistic modeling was used to describe the relationship between 3-year local control (LC3y) and BED. RESULTS: The estimated alpha/beta ratio was 13 Gy (95% confidence interval [CI], 2.5-69 Gy) for EBRT and 24 Gy (95% CI, 1.3-460 Gy) for EBRT and brachytherapy combined. There is evidence for an overall dose-response relationship. After an increase in total dose of 10 Gy, the odds of LC3y increase by a factor of 1.44 (95% CI, 1.23-1.70) for EBRT and 1.47 (95% CI, 1.25-1.72) for the data sets of EBRT and brachytherapy combined. CONCLUSION: With the clinical data currently available, a reliable estimation of the alpha/beta ratio for bladder cancer is not feasible. It seems reasonable to use a conventional alpha/beta ratio of 10-15 Gy. Dose escalation could significantly increase local control. There is no evidence to support short overall treatment times or large fraction sizes in radiotherapy for bladder cancer.

Brachytherapy↗