RESUMEN
BACKGROUND: During the recent years, a new theory postulating that lack of early childhood infections would increase the prevalence rate of allergies has rapidly gained momentum. This hygiene hypothesis has been widely disseminated to the general public and it has been suggested that vaccinations would accordingly indirectly increase rates of atopy. We thus investigated associations between acute infections, infection pressure (i.e. number of daily child contacts) and atopy in one of the largest population-based medical surveys ever published in the medical literature. METHODS: Almost all Finns born between 1976 and 1984 and a sample of older teenagers aged up to 19 years (n=5 47 190) were vaccinated and questioned to establish clinical history of mumps and rubella and manifestations of atopy (rhinoconjunctivitis, eczema, and asthma) in 1982-1986. A subsample (n=37 733) including all those subjects who were vaccinated during the first 2 months of the measles, mumps, and rubella (MMR) programme were also queried information about upper respiratory infections (URIs) and infection pressure. Crude and adjusted prevalence ratios of atopy among those with infectious disease history compared with those without it were calculated. RESULTS: The risk of URI and a history of mumps and rubella increased with the number of daily contacts. This association was apparent especially among the youngest subjects with regard to URIs whereas the proportion with histories of mumps and rubella increased with increasing infection pressure more clearly among the 6-year-olds. Atopy was not associated with daily child contacts among pre-schoolers. Children with histories of repeated URIs and MMR diseases had substantially more atopy than those with lower URI or MMR disease rates. CONCLUSIONS: Atopic subjects seem to be especially prone to clinically apparent acute respiratory tract infections, and might be in particular need of protection by immunizations. This study does not support the idea that the prevalence of atopy in affluent countries would be affected from disappearing respiratory tract infections.
Asunto(s)
Enfermedades Transmisibles/inmunología , Hipersensibilidad/inmunología , Enfermedad Aguda , Adolescente , Asma/epidemiología , Asma/inmunología , Niño , Enfermedades Transmisibles/epidemiología , Conjuntivitis Alérgica/epidemiología , Conjuntivitis Alérgica/inmunología , Eccema/epidemiología , Eccema/inmunología , Humanos , Hipersensibilidad/epidemiología , Lactante , Sarampión/epidemiología , Sarampión/inmunología , Paperas/epidemiología , Paperas/inmunología , Vigilancia de la Población/métodos , Prevalencia , Infecciones del Sistema Respiratorio/epidemiología , Infecciones del Sistema Respiratorio/inmunología , Rinitis Alérgica Estacional/epidemiología , Rinitis Alérgica Estacional/inmunología , Rubéola (Sarampión Alemán)/epidemiología , Rubéola (Sarampión Alemán)/inmunologíaRESUMEN
A liquid chromatography-tandem mass spectrometry (LC-MS/MS) method is presented for the simultaneous screening and quantitation of 18 antihistamine drugs in blood samples. Sample pretreatment involved liquid-liquid extraction of the basic antihistamines followed by a second extraction of the acidic antihistamines. The recoveries were 43-113% for basic drugs and 23-66% for acidic drugs. The combined extracts were run by LC on C(18) reversed phase column using acetonitrile-ammonium acetate mobile phase at pH 3.2. The mass spectrometric analysis was performed with a triple stage quadrupole mass analyzer. Screening was performed using multiple reaction monitoring (MRM) and any compounds tentatively identified as antihistamine drugs were then automatedly verified by their Product Ion Spectra in a subsequent MS/MS run. Quantitation was based on the MRM data from the screening step. In validation tests, the method showed good linearity at the relevant concentrations. The attained limits of quantitation varied between 0.0005 and 0.01mg/l in blood and were lower than the therapeutic concentrations (C(max)). The limits for identification by Product Ion Spectra were also lower than C(max), except for clemastine, which has exceptionally low concentrations in blood. The intra-assay relative standard deviations were better than 10% and the inaccuracy varied between 39% for levocabastine and 5% for cyclizine, the majority of the values being <20%.
Asunto(s)
Cromatografía Liquida/métodos , Antagonistas de los Receptores Histamínicos H1/sangre , Espectrometría de Masas/métodos , Humanos , Modelos Lineales , Reproducibilidad de los ResultadosRESUMEN
BACKGROUND: alpha-tocopherol supplementation significantly reduced risk of prostate cancer in the Alpha-Tocopherol Beta-Carotene Cancer Prevention (ATBC) Study. Sex hormones are thought to be involved in the etiology of prostate cancer. We examined whether long-term supplementation with alpha-tocopherol modified serum hormone levels. METHODS: Men who were cancer-free consumed > or = 90% of the study capsules, and who had both baseline and follow-up blood available, were eligible for the study. One hundred men who received alpha-tocopherol were matched on age, study center, and length of time between blood draws to 100 men who received a placebo. Multivariate linear regression models which allowed for a separate intercept for each matched pair were used to evaluate the effect of alpha-tocopherol supplementation on follow-up hormone concentrations. RESULTS: Compared to men who received a placebo, we found significantly lower serum androstenedione (P = 0.04) and testosterone (P = 0.04) concentrations among men who received alpha-tocopherol, after controlling for baseline hormone level, follow-up serum cholesterol concentration, body mass index, smoking, and fasting time. Geometric mean (95% confidence interval; CI) androstenedione concentration among men who received alpha-tocopherol was 145 ng/dl (CI, 137-153) after adjusting for covariates, compared to 158 ng/dl (CI, 148-167) among men who received a placebo. Mean testosterone concentrations for men who received alpha-tocopherol and placebo were 539 (CI, 517-562) and 573 (CI, 549-598) ng/dl, respectively. CONCLUSIONS: These results suggest that long-term alpha-tocopherol supplementation decreases serum androgen concentrations, and could have been one of the factors contributing to the observed reduction in incidence and mortality of prostate cancer in the alpha-tocopherol treatment group of the ATBC Study.
Asunto(s)
Androstenodiona/sangre , Neoplasias de la Próstata/sangre , Testosterona/sangre , Vitamina E/administración & dosificación , Consumo de Bebidas Alcohólicas , Colesterol/sangre , Deshidroepiandrosterona/sangre , Ingestión de Alimentos , Estudios de Seguimiento , Humanos , Modelos Lineales , Masculino , Persona de Mediana Edad , Análisis Multivariante , Prolactina/sangre , Neoplasias de la Próstata/prevención & control , Radioinmunoensayo , Análisis de Regresión , Globulina de Unión a Hormona Sexual/análisis , FumarRESUMEN
Many countries use trivalent measles-mumps-rubella (MMR) vaccine for their mumps and rubella immunization programs. In Finland, a national 2-dose MMR vaccination program for children, free of charge and on a voluntary basis, was launched in 1982. Serological confirmation of all suspected cases of mumps and rubella has been required since 1987. Despite intensive surveillance, no persistent sequelae or deaths attributable to vaccination have been detected. Indigenous mumps and rubella were eliminated in 1996, but 4 imported cases of mumps and 2 of rubella occurred from 1997 to 1999. Lack of secondary cases indicates sufficient immunity in the community. Compared with an epidemic year, up to thousands of cases of mumps meningoencephalitis and orchitis and around 50 cases of congenital rubella syndrome are now avoided annually. A 2-dose vaccine regimen in children during the last 17 years (1983-1999) has interrupted circulation of the target viruses entirely. Finland is the first country documented to be free of indigenous mumps and rubella (measles was eliminated in 1996). Despite the ongoing possibility of imported disease, major outbreaks probably can be avoided by maintaining high vaccination coverage and the 2-dose policy. JAMA. 2000;284:2643-2647.
Asunto(s)
Programas de Inmunización , Vacuna contra el Sarampión-Parotiditis-Rubéola/administración & dosificación , Paperas/epidemiología , Rubéola (Sarampión Alemán)/epidemiología , Niño , Finlandia/epidemiología , Política de Salud , Humanos , Paperas/prevención & control , Rubéola (Sarampión Alemán)/prevención & controlRESUMEN
OBJECTIVE: Revaccination policies adopted in many countries to control measles have raised various safety issues including those concerning the second vaccine dose. We performed a prospective, double-blind, crossover trial among twins receiving a measles-mumps-rubella (MMR) vaccine. STUDY DESIGN: The study comprised 1162 monozygous and heterozygous twins, each of whom randomly received placebo and then vaccine, or vice versa, 3 weeks apart, at 14 to 83 months of age. Most of the oldest children had previously been vaccinated against measles, and one half of the remainder of children had had the disease. Symptoms and signs were recorded daily on structured forms. Statistical methods included a complex analysis of the vaccine attributability of the symptoms and conditional logistic regression. RESULTS: Vaccination-attributable events occurred in 6% overall. At 14 to 18 months of age, reactions developed between days 6 and 14, peaking at day 10. The clearest vaccine-attributable effect was fever exceeding 101.3 degrees F (38. 5 degrees C; odds ratio: 3.28; 95% confidence interval: 2.23-4.82; P <.001), but the same trend was found for rash, arthralgia, conjunctivitis, staying in bed, drowsiness, and irritability. At 6 years of age, systemic reactions occurred 5 to 15 times less frequently, only arthralgia being associated with vaccination. Zygocity, gender, history of allergy, or infections did not modify reactions. Instead, respiratory symptoms developed within days postinjection to a level of 15% to 20% without subsequent decline and with no difference between vaccinees and placebo recipients. CONCLUSION: Vaccination was avoided during infections, but many small children became mildly ill within a week or so with no relation to vaccination (the healthy vaccinee effect). MMR vaccine was virtually nonreactogenic when given at 6 years of age. vaccine, measles, mumps, rubella, reactogenicity, adverse events, zygocity, healthy vaccinee effect.
Asunto(s)
Vacuna contra el Sarampión-Parotiditis-Rubéola/inmunología , Factores de Edad , Formación de Anticuerpos/inmunología , Artralgia/inducido químicamente , Niño , Preescolar , Conjuntivitis/inducido químicamente , Estudios Cruzados , Método Doble Ciego , Exantema/inducido químicamente , Femenino , Fiebre/inducido químicamente , Humanos , Lactante , Masculino , Vacuna contra el Sarampión-Parotiditis-Rubéola/efectos adversos , Placebos , Gemelos Dicigóticos , Gemelos MonocigóticosRESUMEN
BACKGROUND AND AIMS: The risk of gastric cancer (GCA) is increased in atrophic gastritis. A low serum pepsinogen group I (SPGI) level is a good serologic indicator of atrophic gastritis of the gastric corpus and fundus, and can be used for diagnosis of subjects with atrophic gastritis and of increased risk for GCA. The present study was undertaken to investigate whether SPGI assay and a diagnostic gastroscopy could enable the diagnosis of GCA at an early stage. MATERIAL AND METHODS: The study was carried out as part of the Alpha-Tocopherol, Beta-Carotene Cancer prevention study (ATBC study) in Finland, in which 22,436 male smokers aged 50-69 years were screened by SPGI. Low SPGI levels (< 25 microg/l) were found in 2196 (9.8%) men. Upper GI endoscopy (gastroscopy) was performed in 1344 men (61%) and 78% of these had moderate or severe atrophic corpus gastritis in endoscopic biopsies. A control series of 136 men from the ATBC study cohort with abdominal symptoms, but with SPGI > or = 50 microg/l were similarly endoscopied, and 2.2% of these had corpus atrophy. RESULTS: Neoplastic alterations were found in 63 (4.7%; 95% CI: 3.6%-5.8%) of the 1344 endoscopied men with low SPGI levels. Of these, 42 were definite dysplasias of low grade, 7 dysplasias of high grade, 11 invasive carcinomas, of which 7 were 'early' cancers, and 3 carcinoid tumors. In the control series, 1 man (0.7%) of the 136 men had a definite low-grade dysplasia. Thus, 18 (1.3%; 95% CI 0.7%-2.0%) cases with 'severe' neoplastic lesions (4 advanced cancers, 7 early cancers and 7 dysplasias of high grade) were found in the low SPGI group, but there were none in the control group. All four patients with advanced cancer died from the malignancy within 5 years (mean survival time 2.5 years), whereas surgical treatment in all those with early cancer or high-grade dysplasia was curative. One of the seven patients with early cancer and two of the seven with high-grade dysplasia died within 5 years, but none died from the gastric cancer. Thus, curative treatment was given to 14 of 18 men in whom a malignant lesion was found in gastroscopy. This is about 15% of all gastric cancer cases (92 cases) which were diagnosed within 5 years after SPGI screening in the 22,436 men. Among the gastric cancer cases of the main ATBC study, the 5-year survival rate was 33% (85% of the non-survivors died from gastric cancer). CONCLUSIONS: We conclude that assay of SPGI followed by endoscopy is an approach which can enable the early diagnosis of gastric cancer at a curable stage.
Asunto(s)
Pepsinógeno A/sangre , Lesiones Precancerosas/diagnóstico , Neoplasias Gástricas/diagnóstico , Anciano , Biopsia , Método Doble Ciego , Finlandia/epidemiología , Estudios de Seguimiento , Gastritis Atrófica/sangre , Gastroscopía , Humanos , Masculino , Persona de Mediana Edad , Lesiones Precancerosas/sangre , Lesiones Precancerosas/epidemiología , Estómago/patología , Neoplasias Gástricas/sangre , Neoplasias Gástricas/epidemiología , Tasa de Supervivencia , Factores de TiempoRESUMEN
CONTEXT: High serum or dietary levels of vitamin E and beta carotene appear to be associated with lower risk of stroke, but studies regarding their supplementation have not supported their use in stroke prevention. OBJECTIVE: To determine if vitamin E (dl-alpha tocopherol) and beta carotene supplementations could be used in prevention of stroke in men at high risk for hemorrhagic or ischemic events. DESIGN: Population-based, randomized, double-blind, placebo-controlled, 2 x 2 factorial design trial (the Alpha-Tocopherol, Beta-Carotene Cancer Prevention Study), conducted from April 1985 through April 30, 1993, with median follow-up of 6 years. INTERVENTIONS: Alpha tocopherol, 50 mg; beta carotene, 20 mg; both; or placebo. PARTICIPANTS: From the total male population aged 50 through 69 years in southwestern Finland (n = 290,406), 29,133 male smokers were randomized to 1 of 4 treatment regimens. We excluded 614 men because of previous stroke at baseline, leaving 28, 519. MAIN OUTCOME MEASURES: Incident and fatal subarachnoid and intracerebral hemorrhage, cerebral infarction, and unspecified stroke. RESULTS: Stroke occurred in a total of 1057 men: 85 had subarachnoid and 112 had intracerebral hemorrhage, 807 had cerebral infarction, and 53 had unspecified stroke. Within 90 days from onset, 160 men died of stroke. Vitamin E supplementation increased the risk of subarachnoid hemorrhage (relative risk [RR], 2.45; 95% confidence interval [CI], 1.08-5.55) and decreased risk of cerebral infarction (RR, 0.70; 95% CI, 0.55-0.89) in hypertensive men but had no effect among normotensive men. Furthermore, it decreased the risk of cerebral infarction, without elevating the risk of subarachnoid hemorrhage, among hypertensive men with concurrent diabetes (RR, 0.33; 95% CI, 0.14-0.78). Beta carotene supplementation appeared to increase the risk of intracerebral hemorrhage and modestly decrease that of cerebral infarction among men with greater alcohol consumption. CONCLUSION: Vitamin E supplementation may prevent ischemic stroke in high-risk hypertensive patients, but further studies are needed. Arch Neurol. 2000;57:1503-1509
Asunto(s)
Suplementos Dietéticos , Accidente Cerebrovascular/prevención & control , Vitamina E/uso terapéutico , beta Caroteno/uso terapéutico , Método Doble Ciego , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Factores de Riesgo , Accidente Cerebrovascular/mortalidad , Resultado del Tratamiento , Vitamina E/sangre , beta Caroteno/sangreRESUMEN
Chlorophenols contaminated the drinking water system and a local lake in the village of Järvelä in southern Finland. Period prevalence rates of symptoms, signs and diseases among the residents 15 years or older who responded (69%) to a survey in the contaminated area (1773 subjects) were compared with the rates of three uncontaminated areas (2018 subjects). Gastrointestinal and skin symptoms, in particular, were significantly (p < 0.05) more common in the contaminated area than in each control area. Nausea, general malaise, headache, anorexia, exceptional tiredness, and respiratory infections were significantly increased compared to the control areas combined. A dose-response was also observed: higher consumption of drinking water and contaminated fish further significantly increased (p < 0.05) reported symptoms. In conclusion, long-term use of chlorophenol polluted household water and fish can cause symptoms already familiar in connection with occupational chlorophenol exposures.
Asunto(s)
Clorofenoles , Enfermedades Gastrointestinales/epidemiología , Enfermedades de la Piel/epidemiología , Contaminación Química del Agua , Abastecimiento de Agua , Finlandia/epidemiología , Enfermedades Gastrointestinales/inducido químicamente , Humanos , Oportunidad Relativa , Prevalencia , Enfermedades de la Piel/inducido químicamenteRESUMEN
Failure to seroconvert (primary vaccine failure) is believed to be the principal reason (approx. > 95%) why some vaccinees remain susceptible to measles and is often attributed to the persistence of maternal antibodies in children vaccinated at a young age. Avidity testing is able to separate primary from secondary vaccine failures (waning and/or incomplete immunity), but has not been utilized in measles epidemiology. Low-avidity (LA) and high-avidity (HA) virus-specific IgG antibodies indicate primary and secondary failure, respectively. Measles vaccine failures (n = 142; mean age 10.1 years, range 2-22 years) from an outbreak in 1988-9 in Finland were tested for measles-virus IgG avidity using a protein denaturating EIA. Severity of measles was recorded in 89 failures and 169 non-vaccinees (mean age 16.2 years, range 2-22 years). The patients with HA antibodies (n = 28) tended to have clinically mild measles and rapid IgG response. Among failures vaccinated at < 12, 12-15 and > 15 months of age with single doses of Schwarz-strain vaccine in the 1970s, 50 (95% CI 1-99), 36 (CI 16-56) and 25% (CI 8-42) had HA antibodies, respectively. When a single measles, mumps and rubella (MMR) vaccine had been given after 1982 at 15 months of age, only 7% (CI 0-14) showed HA antibodies. Omitting re-vaccinees and those vaccinated at < 15 months, Schwarz-strain recipients had 3.6 (CI 1.1-11.5) higher occurrence of HA responses compared to MMR recipients. Apart from one municipality, where even re-vaccinees had high risk of primary infection, 89% (CI 69 to approximately 100) of the infected re-vaccinees had an HA response. Secondary measles-vaccine failures are more common than was more previously thought, particularly among individuals vaccinated in early life, long ago, and among re-vaccinees. Waning immunity even among individuals vaccinated after 15 months of age, without the boosting effect of natural infections should be considered a relevant possibility in future planning of vaccination against measles.
Asunto(s)
Anticuerpos Antivirales/sangre , Especificidad de Anticuerpos/inmunología , Inmunoglobulina G/sangre , Vacuna Antisarampión/inmunología , Sarampión/inmunología , Sarampión/prevención & control , Adolescente , Adulto , Distribución por Edad , Factores de Edad , Niño , Preescolar , Brotes de Enfermedades , Femenino , Finlandia/epidemiología , Humanos , Masculino , Sarampión/sangre , Sarampión/epidemiología , Vacuna Antisarampión/uso terapéutico , Factores de Tiempo , Insuficiencia del Tratamiento , VacunaciónRESUMEN
BACKGROUND: Some epidemiological investigations suggest that higher intake or biochemical status of vitamin E and beta-carotene might be associated with reduced risk of colorectal cancer. METHODS: We tested the effects of alpha-tocopherol and beta-carotene supplementation on the incidence of colorectal cancer in the Alpha-Tocopherol, Beta-Carotene Cancer Prevention (ATBC) Study, a double-blind, placebo-controlled trial among 29,133 50-69-year-old male cigarette smokers. Participants were randomly assigned to receive alpha-tocopherol (50 mg), beta-carotene (20 mg), both agents, or a placebo daily for 5-8 years. Incident colorectal cancers (n = 135) were identified through the nationwide cancer registry, and 99% were histologically confirmed. Intervention effects were evaluated using survival analysis and proportional hazards models. RESULTS: Colorectal cancer incidence was somewhat lower in the alpha-tocopherol arm compared to the no alpha-tocopherol arm, but this finding was not statistically significant (relative risk (RR) = 0.78, 95% confidence interval (CI) 0.55-1.09; log-rank test p = 0.15). Beta-carotene had no effect on colorectal cancer incidence (RR = 1.05, 95% CI 0.75-1.47; log-rank test p = 0.78). There was no interaction between the two substances. CONCLUSION: Our study found no evidence of a beneficial or harmful effect for beta-carotene in colorectal cancer in older male smokers, but does provide suggestive evidence that vitamin E supplementation may have had a modest preventive effect. The latter finding is in accord with previous research linking higher vitamin E status to reduced colorectal cancer risk.
Asunto(s)
Neoplasias Colorrectales/epidemiología , Neoplasias Colorrectales/prevención & control , Suplementos Dietéticos , Vitamina E/administración & dosificación , beta Caroteno/administración & dosificación , Anciano , Neoplasias Colorrectales/mortalidad , Método Doble Ciego , Finlandia/epidemiología , Humanos , Incidencia , Masculino , Persona de Mediana Edad , Factores de Riesgo , FumarRESUMEN
CONTEXT: Many recent cross-sectional studies have suggested that lack of early exposure to communicable diseases, including measles, in affluent countries may have increased rates of atopic disease. OBJECTIVE: To study the association between natural measles infection and atopy. DESIGN AND SETTING: Cross-sectional nationwide study in Finland using data gathered between November 1, 1982, and June 30, 1986. SUBJECTS: A total of 547910 individuals aged 14 months to 19 years who at the time of measles-mumps-rubella (MMR) vaccination had relevant information collected on the occurrence of measles and allergic rhinitis, eczema, and asthma. MAIN OUTCOME MEASURES: Lifetime occurrence of atopic manifestations in subjects who had had measles compared with those who had not, expressed as age-specific and age-adjusted prevalence ratios. RESULTS: The age-adjusted prevalence ratio of atopic manifestations among those who had had measles (n = 20 690) compared with those who had not (n = 527 220) was 1.32 (95% confidence interval [CI], 1.27-1.36) for eczema, 1.41 (95% CI, 1.33-1.49) for rhinitis, and 1.67 (95% CI, 1.54-1.79) for asthma. The positive association between measles and atopy was evident at all ages, in both urban and rural dwellers, and among subjects with many or few contacts at home or in day care. CONCLUSIONS: Based on our data, measles and atopy occur more frequently together than expected, which does not support the hypothesis that experiencing natural measles infection offers protection against atopic disease.
Asunto(s)
Hipersensibilidad Inmediata/epidemiología , Hipersensibilidad Inmediata/virología , Sarampión/inmunología , Adolescente , Asma/epidemiología , Asma/virología , Niño , Preescolar , Estudios Transversales , Recolección de Datos , Eccema/epidemiología , Eccema/virología , Finlandia/epidemiología , Humanos , Lactante , Sarampión/epidemiología , Prevalencia , Rinitis Alérgica Perenne/epidemiología , Rinitis Alérgica Perenne/virologíaRESUMEN
Observational data suggest that diets rich in fruits and vegetables and with high serum levels of antioxidants are associated with decreased incidence and mortality of stroke. We studied the effects of alpha-tocopherol and beta-carotene supplementation. The incidence and mortality of stroke were examined in 28 519 male cigarette smokers aged 50 to 69 years without history of stroke who participated in the Alpha-Tocopherol, Beta-Carotene Cancer Prevention Study (ATBC Study). The daily supplementation was 50 mg alpha-tocopherol, 20 mg beta-carotene, both, or placebo. The median follow-up was 6.0 years. A total of 1057 men suffered from incident stroke: 85 men had subarachnoid hemorrhage; 112, intracerebral hemorrhage; 807, cerebral infarction; and 53, unspecified stroke. Deaths due to stroke within 3 months numbered 38, 50, 65, and 7, respectively (total 160). alpha-Tocopherol supplementation increased the risk of subarachnoid hemorrhage 50% (95% CI -3% to 132%, P=0.07) but decreased that of cerebral infarction 14% (95% CI -25% to -1%, P=0.03), whereas beta-carotene supplementation increased the risk of intracerebral hemorrhage 62% (95% CI 10% to 136%, P=0.01). alpha-Tocopherol supplementation also increased the risk of fatal subarachnoid hemorrhage 181% (95% CI 37% to 479%, P=0.01). The overall net effects of either supplementation on the incidence and mortality from total stroke were nonsignificant. alpha-Tocopherol supplementation increases the risk of fatal hemorrhagic strokes but prevents cerebral infarction. The effects may be due to the antiplatelet actions of alpha-tocopherol. beta-Carotene supplementation increases the risk of intracerebral hemorrhage, but no obvious mechanism is available.
Asunto(s)
Fumar/efectos adversos , Accidente Cerebrovascular/prevención & control , Vitamina E/administración & dosificación , beta Caroteno/administración & dosificación , Anciano , Hemorragia Cerebral/epidemiología , Hemorragia Cerebral/mortalidad , Hemorragia Cerebral/prevención & control , Infarto Cerebral/epidemiología , Infarto Cerebral/mortalidad , Infarto Cerebral/prevención & control , Método Doble Ciego , Humanos , Masculino , Persona de Mediana Edad , Accidente Cerebrovascular/epidemiología , Accidente Cerebrovascular/mortalidad , Hemorragia Subaracnoidea/epidemiología , Hemorragia Subaracnoidea/mortalidad , Hemorragia Subaracnoidea/prevención & control , Vitamina E/efectos adversos , beta Caroteno/efectos adversosRESUMEN
OBJECTIVES: Epidemiological studies have suggested a protective effect of vegetables and fruits on urinary tract cancer but the possible protective nutrients are unknown. We studied the effect of alpha-tocopherol (a form of vitamin E) and beta-carotene supplementation on urinary tract cancer in the Alpha-Tocopherol, Beta-Carotene Cancer Prevention (ATBC) Study. METHODS: A total of 29,133 male smokers aged 50-69 years from southwestern Finland were randomly assigned to receive alpha-tocopherol (50 mg), beta-carotene (20 mg), both agents, or a placebo daily for 5-8 years (median 6.1 years). Incident urothelial cancers (bladder, ureter, and renal pelvis; n = 169) and renal cell cancers (n = 102) were identified through the nationwide cancer registry. The diagnoses were centrally confirmed by review of medical records and pathology specimens. The supplementation effects were estimated using a proportional hazards model. RESULTS: Neither alpha-tocopherol nor beta-carotene affected the incidence of urothelial cancer, relative risk 1.1 (95% confidence interval (CI) 0.8-1.5) and 1.0 (95% CI 0.7-1.3), respectively, or the incidence of renal cell cancer, relative risk 1.1 (95% CI 0.7-1.6) and 0.8 (95% CI 0.6-1.3), respectively. CONCLUSION: Long-term supplementation with alpha-tocopherol and beta-carotene has no preventive effect on urinary tract cancers in middle-aged male smokers.
Asunto(s)
Antioxidantes/farmacología , Neoplasias Urológicas/prevención & control , Vitamina E/farmacología , beta Caroteno/farmacología , Anciano , Antioxidantes/administración & dosificación , Suplementos Dietéticos , Humanos , Incidencia , Masculino , Persona de Mediana Edad , Fumar/efectos adversos , Neoplasias Urológicas/epidemiología , Neoplasias Urológicas/mortalidad , Vitamina E/administración & dosificación , beta Caroteno/administración & dosificaciónRESUMEN
BACKGROUND AND PURPOSE: Blood pressure is an important risk factor for stroke, but the roles of serum total and HDL cholesterol, alpha-tocopherol, and beta-carotene are poorly established. We studied these factors in relation to stroke subtypes. METHODS: Male smokers (n=28 519) aged 50 to 69 years without a history of stroke participated in the Alpha-Tocopherol, Beta-Carotene Cancer Prevention (ATBC) Study, a controlled trial to test the effect of alpha-tocopherol and beta-carotene supplementation on cancer. From 1985 to 1993, a total of 1057 men suffered from primary stroke: 85 had subarachnoid hemorrhage; 112, intracerebral hemorrhage; 807, cerebral infarction; and 53, unspecified stroke. RESULTS: Systolic blood pressure > or = 160 mm Hg increased the risk of all stroke subtypes 2.5 to 4-fold. Serum total cholesterol was inversely associated with the risk of intracerebral hemorrhage, whereas the risk of cerebral infarction was raised at concentrations > or = 7.0 mmol/L. The risks of subarachnoid hemorrhage and cerebral infarction were lowered with serum HDL cholesterol levels > or = 0.85 mmol/L. Pretrial high serum alpha-tocopherol decreased the risk of intracerebral hemorrhage by half and cerebral infarction by one third, whereas high serum beta-carotene doubled the risk of subarachnoid hemorrhage and decreased that of cerebral infarction by one fifth. CONCLUSIONS: The risk factor profiles of stroke subtypes differ, reflecting different etiopathology. Because reducing atherosclerotic diseases, including ischemic stroke, by lowering high serum cholesterol is one of the main targets in public health care, further studies are needed to distinguish subjects with risk of hemorrhagic stroke. The performance of antioxidants needs confirmation from clinical trials.
Asunto(s)
Accidente Cerebrovascular/epidemiología , Anciano , Presión Sanguínea , Infarto Cerebral/sangre , Infarto Cerebral/epidemiología , Colesterol/sangre , HDL-Colesterol/sangre , Ensayos Clínicos Controlados como Asunto , Estudios de Seguimiento , Humanos , Hemorragias Intracraneales/sangre , Hemorragias Intracraneales/epidemiología , Masculino , Persona de Mediana Edad , Factores de Riesgo , Fumar/efectos adversos , Accidente Cerebrovascular/sangre , Hemorragia Subaracnoidea/sangre , Hemorragia Subaracnoidea/epidemiología , Vitamina E/sangre , beta Caroteno/sangreRESUMEN
To examine whether vitamin C rich food consumption and related vitamin C intake are associated with the risk of tuberculosis, the authors analyzed 167 incident cases of tuberculosis during a median follow-up time of 6.7 years in a clinical trial cohort of 26,975 Finnish men for whom they had baseline dietary data. A highly statistically significant inverse association between calculated vitamin C intake and the incidence of tuberculosis was found, but adjustment for non-dietary factors weakened the association to nonsignificant. Furthermore, the risk of tuberculosis decreased with increasing intake of fruits, vegetables, and berries independent of vitamin C intake. Subjects who had dietary vitamin C intake >90 mg/day and who consumed more than the average amount of fruits, vegetables, and berries had a significantly lower risk of tuberculosis (adjusted relative risk = 0.40; 95% confidence interval 0.24, 0.69). Associations between dietary vitamin C intake and occurrence of various diseases without proper control of confounding have often been interpreted as causal. These findings show that such associations can be confounded even by some other dietary components. Lower tuberculosis incidence in subjects who consumed more fruits, vegetables, and berries poor in vitamin C suggests that other compounds in such a diet may reduce the risk of tuberculosis.
Asunto(s)
Ácido Ascórbico/administración & dosificación , Dieta , Fumar/efectos adversos , Tuberculosis Pulmonar/epidemiología , Anciano , Estudios de Cohortes , Factores de Confusión Epidemiológicos , Encuestas sobre Dietas , Finlandia/epidemiología , Humanos , Incidencia , Masculino , Persona de Mediana Edad , Modelos de Riesgos Proporcionales , Factores de Riesgo , Tuberculosis Pulmonar/prevención & controlRESUMEN
BACKGROUND: Studies on alcohol consumption and incidences of stroke subtypes have suggested distinct dose-response relationships. Blood pressure and HDL cholesterol mediate the effect of alcohol on coronary heart disease, but similar evidence on cerebrovascular diseases is not available. METHODS AND RESULTS: We studied the risk of stroke in 26 556 male cigarette smokers 50 to 69 years of age without history of stroke. The men were categorized as nondrinkers, light (60 g/d) drinkers. A total of 960 men suffered from incident stroke: 83 with subarachnoid and 95 with intracerebral hemorrhage, 733 with cerebral infarction, and 49 with unspecified stroke. The adjusted relative risk of subarachnoid hemorrhage was 1.0 in light drinkers, 1.3 in moderate drinkers, and 1.6 in heavy drinkers compared with nondrinkers. The respective relative risks of intracerebral hemorrhage were 0.8, 0.6, and 1.8; of cerebral infarction, 0.9, 1.2, and 1.5. Systolic blood pressure attenuated the effect of alcohol consumption in all subtypes of stroke, whereas HDL cholesterol strengthened the effect of alcohol in subarachnoid hemorrhage and cerebral infarction but attenuated the effect in intracerebral hemorrhage. CONCLUSIONS: Alcohol consumption may have a distinct dose-response relationship within each stroke subtype-linear in subarachnoid hemorrhage, U-shaped in intracerebral hemorrhage, and J-shaped in cerebral infarction-but further studies are warranted. Systolic blood pressure and HDL cholesterol seem to mediate the effect of alcohol on stroke incidence, but evidently additional mechanisms are involved.
Asunto(s)
Consumo de Bebidas Alcohólicas/efectos adversos , Trastornos Cerebrovasculares/etiología , Fumar/efectos adversos , Anciano , Presión Sanguínea , Hemorragia Cerebral/etiología , Infarto Cerebral/etiología , Trastornos Cerebrovasculares/epidemiología , HDL-Colesterol/sangre , Relación Dosis-Respuesta a Droga , Humanos , Masculino , Persona de Mediana Edad , Factores de Riesgo , Hemorragia Subaracnoidea/etiologíaRESUMEN
BACKGROUND: Double reading is a widely used criterion standard in breast cancer screening despite a lack of evidence of the cost-effectiveness of the second reading. This study evaluates the incremental cost-effectiveness of such a strategy. DESIGN: Cost-effectiveness analysis: Nationwide population-based semi-annual screening program for women aged 50-59 in Finland. Participation rate was 91%. All mammograms (95,423) performed during 1990-1995 in three screening centers of the Finnish Cancer Society were read by two radiologists with gradings recorded. The effectiveness of the double reading was the difference in cancers detected in the double compared to that of the single reading. Incremental costs of the double reading for the health care and non-health care and the time costs were estimated. The main outcome measure was the incremental cost per additional cancer found as a result of the double-reading strategy. RESULTS: The total number of cancers detected with the double and single reading were 290 and 261, respectively. A significantly higher ratio of carcinoma in situ was the causative pathology in cancers detected only by the second reader. The cost per cancer detected with a single reading was US$ 18,340. The incremental cost of any additional cancer found was US$ 25,523, that is, a 39% higher cost per additional cancer found by double reading. CONCLUSIONS: The additional cost per cancer detected by double reading is not drastically higher than with single reading. However, the additional cost per life year saved may be much higher.
Asunto(s)
Neoplasias de la Mama/economía , Mamografía/economía , Neoplasias de la Mama/diagnóstico por imagen , Análisis Costo-Beneficio , Femenino , Finlandia , Humanos , Mamografía/métodos , Tamizaje Masivo , Persona de Mediana Edad , Estudios Multicéntricos como Asunto , Estudios Retrospectivos , Sensibilidad y EspecificidadRESUMEN
BACKGROUND: The aim of this study was to evaluate the cost-effectiveness, from a societal perspective, of the Finnish nationwide breast carcinoma screening program. METHODS: The effects were measured in life-years saved from 1987 to 2020, using data from the nationwide program to the end of 1992. A total of 90,000 women ages 50-59 were invited for screening during the years 1987-89. The total number of participants screened was 76,000. The screening interval was 24 months, with follow-up to the end of 1992. From the beginning of 1993, the estimation model used parameters based on published studies and national cancer statistics. Data on health care and non-health care costs and time costs were obtained from internal accounts of screening units, published studies, national statistics, health market sources, and a questionnaire completed by a sample of 1400 screening attendees. The discount rate, the annual rate of time preference over future costs and life-years saved, was 3%. The main outcome measure was the cost per life-year saved. RESULTS: The estimated number of life-years of life saved was 578, of which 8% occurred 1987-1992. The estimated life-years saved per 1000 screenings was 3.2. The total costs were $11 million in U.S. dollars, i.e., $14.3 million per 100,000 participants. CONCLUSIONS: The cost of breast carcinoma mammographic screening per life-year saved was $18,955 in the base case, ranging from $15,502 to $40,308 according to the different models used in analysis.
Asunto(s)
Neoplasias de la Mama/diagnóstico por imagen , Tamizaje Masivo/economía , Neoplasias de la Mama/economía , Análisis Costo-Beneficio , Femenino , Finlandia , Costos de la Atención en Salud , Humanos , Mamografía/economía , Persona de Mediana Edad , Estudios Retrospectivos , Análisis de SupervivenciaRESUMEN
BACKGROUND: Dietary components may be both causal and protective in cases of pancreatic carcinoma, but the preventive potential of single constituents has not been evaluated. The authors report the effects of alpha-tocopherol and beta-carotene supplementations on the rates of incidence of and mortality from pancreatic carcinoma in a randomized, controlled trial. METHODS: The 29,133 participants in the Alpha-Tocopherol Beta-Carotene Cancer Prevention (ATBC) Study were male smokers who were ages 50-69 years at the time they were randomized into 1 of the following 4 intervention groups: dl-alpha-tocopherol (AT; 50 mg/day), beta-carotene (BC; 20 mg/day), both AT and BC, and placebo. The daily supplementation lasted for 5-8 years. Incident cancers were identified through the national Finnish Cancer Registry and death certificates of the Statistics Finland. Results were analyzed by supplementation with Cox regression models. RESULTS: Effects of both supplementations were statistically nonsignificant. The rate of incidence of pancreatic carcinoma was 25% lower for the men who received beta-carotene supplements (n = 38) compared with the rate for those who did not receive beta-carotene (n = 51) (95% CI, -51% to 14%). Supplementation with alpha-tocopherol (n = 51) increased the rate of incidence by 34% (95% CI, -12% to 105%) compared with the rate for those who did not receive alpha-tocopherol. Mortality from pancreatic carcinoma during the follow-up, adjusted for stage and anatomic location of the tumor, was 19% (95% CI, -47% to 26%) lower among those who received beta-carotene and 11% (95% CI, -28% to 72%) higher among those who received alpha-tocopherol as compared with those who did not receive supplementation. CONCLUSIONS: Supplementation with beta-carotene or alpha-tocopherol does not have a statistically significant effect on the rate of incidence of pancreatic carcinoma or the rate of mortality caused by this disease.
Asunto(s)
Antioxidantes/uso terapéutico , Carcinoma/prevención & control , Neoplasias Pancreáticas/prevención & control , Sistema de Registros , Vitamina E/uso terapéutico , beta Caroteno/uso terapéutico , Anciano , Antioxidantes/administración & dosificación , Carcinoma/mortalidad , Quimioprevención , Estudios de Seguimiento , Humanos , Incidencia , Masculino , Persona de Mediana Edad , Neoplasias Pancreáticas/mortalidad , Fumar , Vitamina E/administración & dosificación , beta Caroteno/administración & dosificaciónRESUMEN
OBJECTIVE: To study measles risk after revaccination. DESIGN: A population-based case-control study during an epidemic season. MAIN OUTCOME MEASURE: Relative serologically confirmed measles risk. PARTICIPANTS AND METHODS: 153 vaccinated cases, mostly from rural areas, were serologically confirmed as measles at the central laboratory in 1988-89. A randomly selected group of 453 controls from either municipalities of vaccinated cases or from areas where measles attack rate was > 600/10(5), was identified via the population registry. Vaccination and measles histories of cases and controls were determined from official vaccination cards. RESULTS: Once and twice vaccinated had crude relative risk 15.6 and 2.3 compared with thrice vaccinated. When cases who had received their first vaccination at less than 14 months of age were omitted from analysis, once vaccinated had 4.0 (95% CI 1.2, 16.6) times higher age adjusted measles risk compared with twice vaccinated. When, omission was extended to cases from one particular municipality where even revaccinees had high measles risk during an explosive outbreak the corresponding risk ratio was 17.8 (2.8, 67.8). CONCLUSIONS: Twice vaccinated have better protection against epidemic measles compared with single dose recipients.