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1.
JAMA Ophthalmol ; 140(7): 707-714, 2022 07 01.
Artículo en Inglés | MEDLINE | ID: mdl-35679030

RESUMEN

Importance: Results of several small randomized clinical trials have suggested that supplements of marine ω-3 fatty acids may be beneficial in treating signs and symptoms of dry eye disease (DED). However, randomized clinical trial data to examine whether ω-3 fatty acid supplements can prevent DED are lacking. Objective: To evaluate whether long-term daily supplementation with marine ω-3 fatty acids prevents the development of DED. Design, Setting, and Participants: This was a prespecified ancillary study of the Vitamin D and Omega-3 Trial (VITAL), a nationwide randomized double-blind placebo-controlled 2 × 2 factorial trial of vitamin D and marine ω-3 fatty acids in the primary prevention of cancer and cardiovascular disease. Participants in this ancillary study were 23 523 US adults (men 50 years and older and women 55 years and older) who at study entry were free of a previous diagnosis of DED and were not experiencing severe dry eye symptoms. Participants were enrolled from November 2011 to March 2014, and treatment and follow-up ended on December 31, 2017. Data were analyzed from January 2020 to August 2021. Interventions: Marine ω-3 fatty acids, 1 g per day. Main Outcomes and Measures: The primary end point was incident clinically diagnosed DED confirmed by review of the medical records. The secondary end point was a composite of all confirmed incident clinically diagnosed DED cases plus all incident reports of severe DED symptoms. Results: The mean (SD) age of the 23 523 participants included in the analysis was 67.0 (7.0) years, and 11 349 participants (48.3%) were women. The cohort included 4610 participants (20.0%) who self-identified as Black, 16 481 (71.6%) who self-identified as non-Hispanic White, and 1927 (8.4%) of other racial or ethnic groups or who declined to respond, consolidated owing to small numbers, including American Indian or Alaska Native, Asian, Hispanic or Latino, and Native Hawaiian or Other Pacific Islander. During a median (range) 5.3 (3.8-6.1) years of treatment and follow-up, 472 of 23 523 participants (2.0%) experienced a medical record-confirmed diagnosis of DED. There was no difference in diagnosed DED by randomized ω-3 fatty acid assignment (232 of 11 757 participants [2.0%] with end points in the treated group vs 240 of 11 766 [2.0%] with end points in the placebo group; hazard ratio, 0.97; 95% CI, 0.81-1.16). Similarly, there was no difference between groups for the secondary end point of diagnosed DED plus incident severe DED symptoms (1044 participants [8.9%] with end points in the treated group vs 1074 [9.1%] with end points in the placebo group; hazard ratio, 0.97; 95% CI, 0.89-1.06). Conclusions and Relevance: In this randomized clinical trial, long-term supplementation with 1 g per day of marine ω-3 fatty acids for a median (range) of 5.3 (3.8-6.1) years did not reduce the incidence of diagnosed DED or a combined end point of diagnosed DED or incident severe DED symptoms. These results do not support recommending marine ω-3 fatty acid supplementation to reduce the incidence of DED. Trial Registration: ClinicalTrials.gov Identifier: NCT01880463.


Asunto(s)
Síndromes de Ojo Seco , Ácidos Grasos Omega-3 , Adulto , Anciano , Suplementos Dietéticos , Método Doble Ciego , Síndromes de Ojo Seco/diagnóstico , Síndromes de Ojo Seco/tratamiento farmacológico , Síndromes de Ojo Seco/epidemiología , Ácidos Grasos Omega-3/uso terapéutico , Femenino , Humanos , Incidencia , Masculino , Vitamina D/uso terapéutico , Vitaminas/uso terapéutico
3.
JAMA Ophthalmol ; 138(12): 1280-1289, 2020 12 01.
Artículo en Inglés | MEDLINE | ID: mdl-33119047

RESUMEN

Importance: Observational studies suggest that higher intake or blood levels of vitamin D and marine ω-3 fatty acids may be associated with lower risks of age-related macular degeneration (AMD). However, evidence from randomized trials is limited. Objective: To evaluate whether daily supplementation with vitamin D3, marine ω-3 fatty acids, or both prevents the development or progression of AMD. Design, Setting, and Participants: This was a prespecified ancillary study of the Vitamin D and Omega-3 Trial (VITAL), a nationwide, placebo-controlled, 2 × 2 factorial design randomized clinical trial of supplementation with vitamin D and marine ω-3 fatty acids for the primary prevention of cancer and cardiovascular disease. Participants included 25 871 men and women in the US. Randomization was from November 2011 to March 2014, and study pill-taking ended as planned on December 31, 2017. Interventions: Vitamin D3 (cholecalciferol), 2000 IU per day, and marine ω-3 fatty acids, 1 g per day. Main Outcomes and Measures: The primary end point was total AMD events, a composite of incident cases of AMD plus cases of progression to advanced AMD among participants with AMD at baseline, based on self-report confirmed by medical record review. Analyses were conducted using the intention-to-treat population. Results: In total, 25 871 participants with a mean (SD) age of 67.1 (7.0) years were included in the trial. Of them, 50.6% were women, 71.3% were self-declared non-Hispanic White participants, and 20.2% were Black participants. During a median (range) of 5.3 (3.8-6.1) years of treatment and follow-up, 324 participants experienced an AMD event (285 incident AMD and 39 progression to advanced AMD). For vitamin D3, there were 163 events in the treated group and 161 in the placebo group (hazard ratio [HR], 1.02; 95% CI, 0.82-1.27). For ω-3 fatty acids, there were 157 events in the treated group and 167 in the placebo group (HR, 0.94; 95% CI, 0.76-1.17). In analyses of individual components for the primary end point, HRs comparing vitamin D3 groups were 1.09 (95% CI, 0.86-1.37) for incident AMD and 0.63 (95% CI, 0.33-1.21) for AMD progression. For ω-3 fatty acids, HRs were 0.93 (95% CI, 0.73-1.17) for incident AMD and 1.05 (95% CI, 0.56-1.97) for AMD progression. Conclusion and Relevance: Neither vitamin D3 nor marine ω-3 fatty acid supplementation had a significant overall effect on AMD incidence or progression. Trial Registration: ClinicalTrials.gov Identifier: NCT01782352.


Asunto(s)
Ácidos Grasos Omega-3/uso terapéutico , Degeneración Macular/prevención & control , Vitamina D/uso terapéutico , Anciano , Suplementos Dietéticos , Progresión de la Enfermedad , Método Doble Ciego , Femenino , Estudios de Seguimiento , Humanos , Incidencia , Degeneración Macular/epidemiología , Masculino , Persona de Mediana Edad , Pronóstico , Factores de Tiempo , Estados Unidos/epidemiología , Vitaminas/uso terapéutico
4.
Ophthalmic Epidemiol ; 25(1): 79-88, 2018 02.
Artículo en Inglés | MEDLINE | ID: mdl-29035128

RESUMEN

PURPOSE: Cross-sectional and case-control studies generally support a direct association between elevated plasma homocysteine and age-related macular degeneration (AMD), but data from prospective studies are limited. We examined the prospective relation of plasma homocysteine level, its dietary determinants, and risk of AMD in a large cohort of apparently healthy male physicians. METHODS: During a mean follow-up of 11.2 years, we identified 146 incident cases of visually significant AMD (responsible for a reduction of visual acuity to 20/30 or worse), and 146 controls matched for age, smoking status, and time of blood draw. We measured concentration of homocysteine in blood samples collected at baseline using an enzymatic assay. and we assessed dietary intake of B vitamins and related compounds betaine and choline with a food frequency questionnaire administered at baseline. RESULTS: AMD was not associated with plasma level of homocysteine; the multivariable-adjusted odds ratio (OR) of AMD comparing the highest and lowest quartile of homocysteine was 1.09 (95% confidence interval [95% CI]: 0.52-2.31; p for trend = 0.99). However, AMD was inversely associated with quartile of intake of total folate (OR: 0.55; 95% CI: 0.24-1.23; p for trend = 0.08), vitamin B6 from food (OR: 0.39; 95% CI: 0.17-0.88; p for trend = 0.01), and betaine (OR: 0.53; 95% CI: 0.22-1.27; p for trend = 0.048). CONCLUSIONS: These prospective data from a cohort of apparently healthy men do not support a major role for homocysteine in AMD occurrence, but do suggest a possible beneficial role for higher intake of several nutrients involved in homocysteine metabolism.


Asunto(s)
Dieta/métodos , Suplementos Dietéticos , Predicción , Homocisteína/sangre , Degeneración Macular/epidemiología , Vitaminas/uso terapéutico , Anciano , Biomarcadores/sangre , Estudios Transversales , Método Doble Ciego , Estudios de Seguimiento , Humanos , Incidencia , Degeneración Macular/sangre , Degeneración Macular/prevención & control , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Valores de Referencia , Estados Unidos/epidemiología , Agudeza Visual
5.
J Bone Miner Res ; 32(12): 2331-2338, 2017 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-29244251

RESUMEN

Epidemiologic studies have demonstrated an association of elevated plasma homocysteine levels with greater bone resorption and fracture risk. Vitamins B12 , B6 , and folic acid are cofactors in homocysteine metabolism, and supplementation with B vitamins is effective in lowering homocysteine levels in humans. However, randomized trials of supplemental B vitamins for reduction of fracture risk have been limited. Therefore, we performed an ancillary study to the Women's Antioxidant and Folic Acid Cardiovascular Study (WAFACS), a large randomized trial of women with preexisting cardiovascular disease or three or more coronary risk factors, to test whether a daily B vitamin intervention including folic acid (2.5 mg/day), vitamin B6 (50 mg/day), and vitamin B12 (1 mg/day) reduces nonspine fracture risk over 7.3 years of treatment and follow-up. Among 4810 women, we confirmed 349 nonspine fracture cases by centralized review of medical records. In a substudy of 300 women (150 in treatment group and 150 controls) with paired plasma samples at randomization and follow-up (7.3 years later), we measured two bone turnover markers, including C-terminal cross-linking telopeptide of type I collagen (CTX) and intact type I procollagen N-propeptide (P1NP). In Cox proportional hazards models based on intention-to-treat, we found no significant effects of B vitamin supplementation on nonspine fracture risk (relative hazard = 1.08; 95% confidence interval, 0.88 to 1.34). In a nested case-cohort analysis, there were no significant effects of B vitamins on fracture risk among women with elevated plasma homocysteine levels, or low levels of vitamins B12 or B6 , or folate at baseline. Furthermore, treatment with B vitamins had no effect on change in markers of bone turnover. We found no evidence that daily supplementation with B vitamins reduces fracture risk or rates of bone metabolism in middle-aged and older women at high risk of cardiovascular disease. © 2017 American Society for Bone and Mineral Research.


Asunto(s)
Suplementos Dietéticos , Ácido Fólico/uso terapéutico , Fracturas Óseas/tratamiento farmacológico , Vitamina B 12/uso terapéutico , Vitamina B 6/uso terapéutico , Anciano , Biomarcadores/sangre , Remodelación Ósea , Estudios de Cohortes , Femenino , Estudios de Seguimiento , Fracturas Óseas/sangre , Fracturas Óseas/epidemiología , Homocisteína/sangre , Humanos , Incidencia , Persona de Mediana Edad , Factores de Riesgo , Resultado del Tratamiento , Vitamina B 6/sangre
6.
JAMA Cardiol ; 2(6): 617-625, 2017 06 01.
Artículo en Inglés | MEDLINE | ID: mdl-28384735

RESUMEN

Importance: Long-term multivitamin use had no effect on risk of cardiovascular disease (CVD) in the Physicians' Health Study II. Baseline nutritional status may have modified the lack of effect. Objective: To investigate effect modification by various baseline dietary factors on CVD risk in the Physicians' Health Study II. Design, Setting, and Participants: The Physicians' Health Study II was a randomized, double-blind, placebo-controlled trial testing multivitamin use (multivitamin [Centrum Silver] or placebo daily) among US male physicians. The Physicians' Health Study II included 14 641 male physicians 50 years or older, 13 316 of whom (91.0%) completed a baseline 116-item semiquantitative food frequency questionnaire and were included in the analyses. This study examined effect modification by baseline intake of key foods, individual nutrients, dietary patterns (Alternate Healthy Eating Index and Alternate Mediterranean Diet Score), and dietary supplement use. The study began in 1997, with continued treatment and follow-up through June 1, 2011. Interventions: Multivitamin or placebo daily. Main Outcomes and Measures: Major cardiovascular events, including nonfatal myocardial infarction, nonfatal stroke, and CVD mortality. Secondary outcomes included myocardial infarction, total stroke, CVD mortality, and total mortality individually. Results: In total, 13 316 male physicians (mean [SD] age at randomization, 64.0 [9.0] years in those receiving the active multivitamin and 64.0 [9.1] years in those receiving the placebo) were observed for a mean (SD) follow-up of 11.4 (2.3) years. There was no consistent evidence of effect modification by various foods, nutrients, dietary patterns, or baseline supplement use on the effect of multivitamin use on CVD end points. Statistically significant interaction effects were observed between multivitamin use and vitamin B6 intake on myocardial infarction, between multivitamin use and vitamin D intake on CVD mortality, and between multivitamin use and vitamin B12 intake on CVD mortality and total mortality. However, there were inconsistent patterns in hazard ratios across tertiles of each dietary factor that are likely explained by multiple testing. Conclusions and Relevance: The results suggest that baseline nutritional status does not influence the effect of randomized long-term multivitamin use on major CVD events. Future studies are needed to investigate the role of baseline nutritional biomarkers on the effect of multivitamin use on CVD and other outcomes. Trial Registration: clinicaltrials.gov Identifier: NCT00270647.


Asunto(s)
Enfermedades Cardiovasculares/mortalidad , Dieta , Infarto del Miocardio/epidemiología , Estado Nutricional , Accidente Cerebrovascular/epidemiología , Vitaminas/uso terapéutico , Anciano , Animales , Productos Lácteos , Suplementos Dietéticos , Método Doble Ciego , Peces , Frutas , Humanos , Masculino , Persona de Mediana Edad , Carne Roja , Verduras , Granos Enteros
7.
Trials ; 17: 400, 2016 08 12.
Artículo en Inglés | MEDLINE | ID: mdl-27519183

RESUMEN

BACKGROUND: The Selenium and Vitamin E Cancer Prevention Trial (SELECT) was a randomized, double-blind, placebo-controlled, prostate cancer prevention study funded by the National Cancer Institute and conducted by SWOG (Southwest Oncology Group). A total of 35,533 men were assigned randomly to one of four treatment groups (vitamin E + placebo, selenium + placebo, vitamin E + selenium, placebo + placebo). At the time of the trial's development, NIH had invested substantial resources in evaluating the potential benefits of these antioxidants. To capitalize on the knowledge gained from following a large cohort of healthy, aging males on the effects of selenium and/or vitamin E, ancillary studies with other disease endpoints were solicited. METHODS: Four ancillary studies were added. Each drew from the same population but had independent objectives and an endpoint other than prostate cancer. These studies fell into two categories: those prospectively enrolling and following participants (studies of Alzheimer's disease and respiratory function) and those requiring a retrospective medical record review after a reported event (cataracts/age-related macular degeneration and colorectal screening). An examination of the challenges and opportunities of adding ancillary studies is provided. The impact of the ancillary studies on adherence to SELECT was evaluated using a Cox proportional hazards model. RESULTS: While the addition of ancillary studies appears to have improved participant adherence to the primary trial, this did not come without added complexity. Activation of the ancillary studies happened after the SELECT randomizations had begun resulting in accrual problems to some of the studies. Study site participation in the ancillary trials varied greatly and depended on the interest of the study site principal investigator. Procedures for each were integrated into the primary trial and all monitoring was done by the SELECT Data and Safety Monitoring Committee. The impact of the early closure of the primary trial was different for each of the ancillary trials. CONCLUSIONS: The ancillary studies allowed study sites to broaden the research opportunities for their participants. Their implementation was efficient because of the established infrastructure of the primary trial. Implementation of these ancillary trials took substantial planning and coordination but enriched the overall primary trial. TRIAL REGISTRATION: NCT00006392-S0000 : Selenium and Vitamin E in Preventing Prostate Cancer (SELECT) (4 October 2000). NCT00780689-S0000A :  Prevention of Alzheimer's Disease by Vitamin E and Selenium (PREADVISE) (25 June 2002). NCT00784225-S0000B : Vitamin E and/or Selenium in Preventing Cataract and Age-Related Macular Degeneration in Men on SELECT SWOG-S0000 (SEE) (31 October 2008). NCT00706121-S0000D : Effect of Vitamin E and/or Selenium on Colorectal Polyps in Men Enrolled on SELECT Trial SWOG-S0000 (ACP) (26 June 2008). NCT00063453-S0000C : Vitamin E and/or Selenium in Preventing Loss of Lung Function in Older Men Enrolled on SELECT Clinical Trial SWOG-S0000 (26 June 2003).


Asunto(s)
Anticarcinógenos/administración & dosificación , Antioxidantes/administración & dosificación , Neoplasias de la Próstata/prevención & control , Proyectos de Investigación , Selenio/administración & dosificación , Vitamina E/administración & dosificación , Anciano , Anticarcinógenos/efectos adversos , Antioxidantes/efectos adversos , Bases de Datos Factuales , Método Doble Ciego , Determinación de Punto Final , Humanos , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Neoplasias de la Próstata/diagnóstico , Neoplasias de la Próstata/etiología , Estudios Retrospectivos , Factores de Riesgo , Selenio/efectos adversos , Factores de Tiempo , Resultado del Tratamiento , Estados Unidos , Vitamina E/efectos adversos
8.
Contemp Clin Trials ; 47: 235-43, 2016 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-26767629

RESUMEN

Evidence for a role of supplemental vitamin D and marine omega-3 fatty acids in preventing cancer and cardiovascular disease (CVD) remains inconclusive and insufficient to inform nutritional recommendations for primary prevention. The VITamin D and Omega-A 3 TriaL (VITAL) is an ongoing nationwide, randomized, double-blind, placebo-controlled clinical trial designed to fill this knowledge gap. The study population consists of 25,874 U.S. adults without cancer or CVD at baseline, who were selected only on age (men aged ≥50 and women aged ≥55), with an oversampling of African Americans (n=5,107). In a 2 × 2 factorial design, participants were randomized to one of four supplement groups: [1] active vitamin D3 (cholecalciferol; 2000 IU/d) and active marine omega-3 fatty acids (Omacor® fish oil, eicosapentaenoic acid [EPA] and docosahexaenoic acid [DHA], 1g/d); [2] active vitamin D and omega-3 placebo; [3] vitamin D placebo and active marine omega-3 fatty acids; or [4] vitamin D placebo and omega-3 placebo. The mean length of the randomized treatment period will be 5 years. The randomization was successful, as evidenced by similar distributions of baseline demographic, health, and behavioral characteristics across treatment groups. The similar distribution of known potential confounders across treatment groups strongly suggests that unmeasured or unknown potential confounders are also equally distributed. VITAL is expected to provide important information on the benefit-risk balance of vitamin D and omega-3 fatty acid supplementation when taken for the primary prevention of cancer and CVD.


Asunto(s)
Enfermedades Cardiovasculares/prevención & control , Colecalciferol/uso terapéutico , Suplementos Dietéticos , Ácidos Docosahexaenoicos/uso terapéutico , Ácido Eicosapentaenoico/uso terapéutico , Neoplasias/prevención & control , Prevención Primaria/métodos , Vitaminas/uso terapéutico , Anciano , Anciano de 80 o más Años , Protocolos Clínicos , Método Doble Ciego , Combinación de Medicamentos , Femenino , Humanos , Masculino , Persona de Mediana Edad , Selección de Paciente , Proyectos de Investigación
9.
Ophthalmic Epidemiol ; 23(1): 32-9, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-26786311

RESUMEN

PURPOSE: To examine the incidence of cataract and cataract extraction in a trial of folic acid and vitamins B6 and B12. METHODS: In a randomized, double-masked, placebo-controlled trial, 5442 female health professionals aged 40 years or older with preexisting cardiovascular disease (CVD) or three or more CVD risk factors were randomly assigned to receive a combination of folic acid (2.5 mg/day), vitamin B6 (50 mg/day), and vitamin B12 (1 mg/day), or placebo. A total of 3925 of these women did not have a diagnosis of cataract at baseline and were included in this analysis. The primary endpoint was age-related cataract, defined as an incident age-related lens opacity, responsible for a reduction in best-corrected visual acuity to 20/30 or worse, based on self-report confirmed by medical record review. Extraction of incident age-related cataract was a secondary endpoint of the trial. RESULTS: During an average of 7.3 years of treatment and follow-up, 408 cataracts and 275 cataract extractions were documented. There were 215 cataracts in the combination treatment group and 193 in the placebo group (hazard ratio, HR, 1.10, 95% confidence interval, CI, 0.90-1.33; p = 0.36). For the secondary endpoint of cataract extraction, there were 155 in the combination treatment group and 120 in the placebo group (HR 1.28, 95% CI 1.01-1.63; p = 0.04). CONCLUSIONS: In this large-scale randomized trial of women at high risk of CVD, daily supplementation with a combination of folic acid, vitamin B6, and vitamin B12 had no significant effect on cataract, but may have increased the risk of cataract extraction.


Asunto(s)
Extracción de Catarata/estadística & datos numéricos , Catarata/epidemiología , Ácido Fólico/administración & dosificación , Vitamina B 12/administración & dosificación , Vitamina B 6/administración & dosificación , Complejo Vitamínico B/administración & dosificación , Adulto , Anciano , Enfermedades Cardiovasculares/epidemiología , Enfermedades Cardiovasculares/prevención & control , Método Doble Ciego , Combinación de Medicamentos , Femenino , Personal de Salud , Humanos , Incidencia , Persona de Mediana Edad , Factores de Riesgo
10.
JAMA Ophthalmol ; 133(1): 17-24, 2015 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-25232809

RESUMEN

IMPORTANCE: Observational studies suggest a role for dietary nutrients such as vitamin E and selenium in cataract prevention. However, the results of randomized clinical trials of vitamin E supplements and cataract have been disappointing and are not yet available for selenium. OBJECTIVE: To test whether long-term supplementation with selenium and vitamin E affects the incidence of cataract in a large cohort of men. DESIGN, SETTING, AND PARTICIPANTS: The Selenium and Vitamin E Cancer Prevention Trial (SELECT) Eye Endpoints Study was an ancillary study of the Southwest Oncology Group-coordinated SELECT, a randomized placebo-controlled 4-arm trial of selenium and vitamin E conducted among 35,533 men, 50 years and older for African American participants and 55 years and older for all other men, at 427 participating sites in the United States, Canada, and Puerto Rico. A total of 11,267 SELECT participants from 128 SELECT sites participated in the SELECT Eye Endpoints ancillary study. INTERVENTIONS: Individual supplements of selenium (200 µg per day from L-selenomethionine) and vitamin E (400 IU per day of all rac-α-tocopheryl acetate). MAIN OUTCOMES AND MEASURES: Incident cataract was defined as a lens opacity, age related in origin, and responsible for a reduction in best-corrected visual acuity to 20/30 or worse based on self-reports confirmed by medical record review. Cataract extraction was defined as the surgical removal of an incident cataract. RESULTS: During a mean (SD) of 5.6 (1.2) years of treatment and follow-up, 389 cases of cataract were documented. There were 185 cataracts in the selenium group and 204 in the no selenium group (hazard ratio, 0.91; 95 % CI, 0.75-1.11; P = .37). For vitamin E, there were 197 cases in the treated group and 192 in the placebo group (hazard ratio, 1.02; 95 % CI, 0.84-1.25; P = .81). Similar results were observed for cataract extraction. CONCLUSIONS AND RELEVANCE: These data from a large cohort of apparently healthy men indicate that long-term daily supplementation with selenium and/or vitamin E is unlikely to have a large beneficial effect on age-related cataract. TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT00784225.


Asunto(s)
Envejecimiento , Antioxidantes/administración & dosificación , Extracción de Catarata/estadística & datos numéricos , Catarata/epidemiología , Neoplasias de la Próstata/prevención & control , Selenometionina/administración & dosificación , Vitamina E/administración & dosificación , Anciano , Catarata/diagnóstico , Catarata/prevención & control , Método Doble Ciego , Combinación de Medicamentos , Determinación de Punto Final , Humanos , Incidencia , Masculino , Persona de Mediana Edad , Modelos de Riesgos Proporcionales , Neoplasias de la Próstata/diagnóstico , Factores de Riesgo , Encuestas y Cuestionarios
11.
Am J Clin Nutr ; 100(3): 915-23, 2014 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-25008853

RESUMEN

BACKGROUND: Recent posttrial analysis of a completed randomized trial found an increased risk of prostate cancer among healthy men taking high-dose vitamin E supplements. Trials that examined the effect of vitamin C supplements on cancer risk are few. OBJECTIVE: We examined whether vitamin E or vitamin C supplementation affects the risk of cancer events during posttrial follow-up of the Physicians' Health Study II. DESIGN: Beginning in 1997, a total of 14,641 US male physicians aged ≥50 y were randomly assigned to receive 400 IU of vitamin E every other day, 500 mg of vitamin C daily, or their respective placebos. The vitamin E and vitamin C treatment ended in 2007, and observational follow-up continued through June 2011. RESULTS: This study included an additional 356 cases of incident prostate cancer and 771 total cancers that developed during a mean (maximum) of 2.8 (3.8) y of posttrial observation. During an overall mean of 10.3 (13.8) y, there were a total of 1373 incident prostate cancers and 2669 total cancers documented. In comparison with placebo, vitamin E supplementation had no effect on the incidence of prostate cancer (HR: 0.99; 95% CI: 0.89, 1.10) or total cancers (HR: 1.02; 95% CI: 0.95, 1.10). There was also no effect of vitamin C supplementation on total cancers (HR: 1.02; 95% CI: 0.94, 1.10) or incident prostate cancer (HR: 1.03; 95% CI: 0.93, 1.15). Neither vitamin E nor vitamin C supplementation had effects on other site-specific cancers overall. Stratification by known cancer risk factors, history of cancer, other randomized treatment, and follow-up time showed no significant interactions. CONCLUSION: In this large-scale randomized trial in men, vitamin E and C supplementation had no immediate or long-term effects on the risk of total cancers, prostate cancer, or other site-specific cancers.


Asunto(s)
Antioxidantes/uso terapéutico , Ácido Ascórbico/uso terapéutico , Suplementos Dietéticos , Neoplasias/prevención & control , Vitamina E/uso terapéutico , Anciano , Antioxidantes/efectos adversos , Ácido Ascórbico/efectos adversos , Estudios de Cohortes , Suplementos Dietéticos/efectos adversos , Método Doble Ciego , Estudios de Seguimiento , Humanos , Incidencia , Masculino , Persona de Mediana Edad , Neoplasias/inducido químicamente , Neoplasias/epidemiología , Médicos , Neoplasias de la Próstata/inducido químicamente , Neoplasias de la Próstata/epidemiología , Neoplasias de la Próstata/prevención & control , Factores de Riesgo , Estados Unidos/epidemiología , Vitamina E/efectos adversos
12.
Ophthalmology ; 121(2): 525-34, 2014 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-24268861

RESUMEN

PURPOSE: To test whether long-term multivitamin supplementation affects the incidence of cataract or age-related macular degeneration (AMD) in a large cohort of men. DESIGN: Randomized, double-blind, placebo-controlled trial. PARTICIPANTS: A total of 14,641 US male physicians aged ≥ 50 years. INTERVENTION: Daily multivitamin or placebo. MAIN OUTCOME MEASURES: Incident cataract and visually significant AMD responsible for a reduction in best-corrected visual acuity to 20/30 or worse based on self-reports confirmed by medical record review. RESULTS: During an average of 11.2 years of treatment and follow-up, a total of 1817 cases of cataract and 281 cases of visually significant AMD were confirmed. There were 872 cataracts in the multivitamin group and 945 cataracts in the placebo group (hazard ratio [HR], 0.91; 95% confidence interval [CI], 0.83-0.99; P = 0.04). For visually significant AMD, there were 152 cases in the multivitamin group and 129 cases in the placebo group (HR, 1.19; 95% CI, 0.94-1.50; P = 0.15). CONCLUSIONS: These randomized trial data from a large cohort of middle-aged and older US male physicians indicate that long-term daily multivitamin use modestly and significantly decreased the risk of cataract but had no significant effect on visually significant AMD.


Asunto(s)
Catarata/prevención & control , Suplementos Dietéticos , Degeneración Macular/prevención & control , Vitaminas/administración & dosificación , Anciano , Catarata/epidemiología , Método Doble Ciego , Estudios de Seguimiento , Humanos , Incidencia , Degeneración Macular/epidemiología , Masculino , Persona de Mediana Edad , Médicos , Factores de Riesgo , Encuestas y Cuestionarios , Resultado del Tratamiento , Estados Unidos/epidemiología , Agudeza Visual/fisiología
13.
PLoS One ; 8(9): e76121, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-24098772

RESUMEN

PURPOSE: Dry eye disease affects women twice as often as men, but there is little information on whether dry eye treatments, treatment satisfaction, or the impact of dry eye disease on patients' lives and vision might differ by sex. DESIGN: Questionnaire survey of 4000 participants in the Women's Health Study and the Physicians' Health Studies I and II with a prior report of a diagnosis of DED. METHODS: Among participants who re-confirmed a diagnosis of dry eye disease, we assessed symptoms, treatments, patient satisfaction and impact of dry eye disease, and analyzed differences between men and women using regression models. RESULTS: The final study population consisted of 1,518 women (mean age 70.7 years) and 581 men (mean age 76.7 years), with a mean reported duration of dry eye disease of 10.5 years and 10.1 years, respectively. The frequency and severity of dry eye disease symptoms were higher among women (each P<0.0001), and women reported a greater impact on everyday activities (P<0.0001). Women were more likely to use artificial tears (P<0.0001) use them more often (P<0.0001), and to use Restasis® (P<0.0001), omega-3 fatty acids (P=0.0006), and have punctal occlusion (P=0.005). Women spent more money per month on dry eye treatments (P<0.0001), but reported greater dissatisfaction with treatment side effects (P=0.001), and the amount of time before treatments started working (P=0.03). CONCLUSIONS: These data show that dry eye disease is generally experienced as being more severe among women, having a greater impact on their self-assessed well-being.


Asunto(s)
Síndromes de Ojo Seco/tratamiento farmacológico , Síndromes de Ojo Seco/patología , Satisfacción del Paciente/estadística & datos numéricos , Anciano , Femenino , Humanos , Masculino , Oportunidad Relativa , Análisis de Regresión , Factores Sexuales , Encuestas y Cuestionarios , Resultado del Tratamiento , Estados Unidos
14.
JAMA ; 308(17): 1751-60, 2012 Nov 07.
Artículo en Inglés | MEDLINE | ID: mdl-23117775

RESUMEN

CONTEXT: Although multivitamins are used to prevent vitamin and mineral deficiency, there is a perception that multivitamins may prevent cardiovascular disease (CVD). Observational studies have shown inconsistent associations between regular multivitamin use and CVD, with no long-term clinical trials of multivitamin use. OBJECTIVE: To determine whether long-term multivitamin supplementation decreases the risk of major cardiovascular events among men. DESIGN, SETTING, AND PARTICIPANTS: The Physicians' Health Study II, a randomized, double-blind, placebo-controlled trial of a common daily multivitamin, began in 1997 with continued treatment and follow-up through June 1, 2011. A total of 14,641 male US physicians initially aged 50 years or older (mean, 64.3 [SD, 9.2] years), including 754 men with a history of CVD at randomization, were enrolled. INTERVENTION: Daily multivitamin or placebo. MAIN OUTCOME MEASURES: Composite end point of major cardiovascular events, including nonfatal myocardial infarction (MI), nonfatal stroke, and CVD mortality. Secondary outcomes included MI and stroke individually. RESULTS: During a median follow-up of 11.2 (interquartile range, 10.7-13.3) years, there were 1732 confirmed major cardiovascular events. Compared with placebo, there was no significant effect of a daily multivitamin on major cardiovascular events (11.0 and 10.8 events per 1000 person-years for multivitamin vs placebo, respectively; hazard ratio [HR], 1.01; 95% CI, 0.91-1.10; P = .91). Further, a daily multivitamin had no effect on total MI (3.9 and 4.2 events per 1000 person-years; HR, 0.93; 95% CI, 0.80-1.09; P = .39), total stroke (4.1 and 3.9 events per 1000 person-years; HR, 1.06; 95% CI, 0.91-1.23; P = .48), or CVD mortality (5.0 and 5.1 events per 1000 person-years; HR, 0.95; 95% CI, 0.83-1.09; P = .47). A daily multivitamin was also not significantly associated with total mortality (HR, 0.94; 95% CI, 0.88-1.02; P = .13). The effect of a daily multivitamin on major cardiovascular events did not differ between men with or without a baseline history of CVD (P = .62 for interaction). CONCLUSION: Among this population of US male physicians, taking a daily multivitamin did not reduce major cardiovascular events, MI, stroke, and CVD mortality after more than a decade of treatment and follow-up. TRIAL REGISTRATION: clinicaltrials.gov Identifier: NCT00270647.


Asunto(s)
Enfermedades Cardiovasculares/prevención & control , Infarto del Miocardio/prevención & control , Accidente Cerebrovascular/prevención & control , Vitaminas/uso terapéutico , Anciano , Enfermedades Cardiovasculares/mortalidad , Método Doble Ciego , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Infarto del Miocardio/mortalidad , Médicos , Resultado del Tratamiento
15.
JAMA ; 308(18): 1871-80, 2012 Nov 14.
Artículo en Inglés | MEDLINE | ID: mdl-23162860

RESUMEN

CONTEXT: Multivitamin preparations are the most common dietary supplement, taken by at least one-third of all US adults. Observational studies have not provided evidence regarding associations of multivitamin use with total and site-specific cancer incidence or mortality. OBJECTIVE: To determine whether long-term multivitamin supplementation decreases the risk of total and site-specific cancer events among men. DESIGN, SETTING, AND PARTICIPANTS: A large-scale, randomized, double-blind, placebo controlled trial (Physicians" Health Study II) of 14 641 male US physicians initially aged 50 years or older (mean [SD] age, 64.3 [9.2] years), including 1312 men with a history of cancer at randomization, enrolled in a common multivitamin study that began in 1997 with treatment and follow-up through June 1, 2011. INTERVENTION: Daily multivitamin or placebo. MAIN OUTCOME MEASURES: Total cancer (excluding nonmelanoma skin cancer), with prostate, colorectal, and other site-specific cancers among the secondary end points. RESULTS: During a median (interquartile range) follow-up of 11.2 (10.7-13.3) years, there were 2669 men with confirmed cancer, including 1373 cases of prostate cancer and 210 cases of colorectal cancer. Compared with placebo, men taking a daily multivitamin had a statistically significant reduction in the incidence of total cancer (multivitamin and placebo groups, 17.0 and 18.3 events, respectively, per 1000 person-years; hazard ratio [HR], 0.92; 95% CI, 0.86-0.998; P=.04). There was no significant effect of a daily multivitamin on prostate cancer (multivitamin and placebo groups, 9.1 and 9.2 events, respectively, per 1000 person-years; HR, 0.98; 95% CI, 0.88-1.09; P=.76), colorectal cancer (multivitamin and placebo groups, 1.2 and 1.4 events, respectively, per 1000 person-years; HR, 0.89; 95% CI, 0.68-1.17; P=.39), or other site-specific cancers. There was no significant difference in the risk of cancer mortality (multivitamin and placebo groups, 4.9 and 5.6 events, respectively, per 1000 person-years; HR, 0.88; 95% CI, 0.77-1.01; P=.07). Daily multivitamin use was associated with a reduction in total cancer among 1312 men with a baseline history of cancer (HR, 0.73; 95% CI, 0.56-0.96; P=.02), but this did not differ significantly from that among 13 329 men initially without cancer (HR, 0.94; 95% CI, 0.87-1.02; P=.15; P for interaction=.07). Conclusion In this large prevention trial of male physicians, daily multivitamin supplementation modestly but significantly reduced the risk of total cancer. TRIAL REGISTRATION: clinicaltrials.gov Identifier: NCT00270647.


Asunto(s)
Suplementos Dietéticos , Neoplasias/prevención & control , Vitaminas/uso terapéutico , Anciano , Método Doble Ciego , Humanos , Masculino , Persona de Mediana Edad , Neoplasias/epidemiología , Médicos , Riesgo
16.
Ophthalmology ; 119(8): 1642-9, 2012 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-22503302

RESUMEN

PURPOSE: To test whether supplementation with alternate-day vitamin E or daily vitamin C affects the incidence of the diagnosis of age-related macular degeneration (AMD) in a large-scale randomized trial of male physicians. DESIGN: Randomized, double-masked, placebo-controlled trial. PARTICIPANTS: We included 14 236 apparently healthy United States male physicians aged ≥50 years who did not report a diagnosis of AMD at baseline. METHODS: Participants were randomly assigned to receive 400 international units (IU) of vitamin E or placebo on alternate days, and 500 mg of vitamin C or placebo daily. Participants reported new diagnoses of AMD on annual questionnaires and medical record data were collected to confirm the reports. MAIN OUTCOME MEASURES: Incident diagnosis of AMD responsible for a reduction in best-corrected visual acuity to ≤20/30. RESULTS: After 8 years of treatment and follow-up, a total of 193 incident cases of visually significant AMD were documented. There were 96 cases in the vitamin E group and 97 in the placebo group (hazard ratio [HR], 1.03; 95% confidence interval [CI], 0.78-1.37). For vitamin C, there were 97 cases in the active group and 96 in the placebo group (HR, 0.99; 95% CI, 0.75-1.31). CONCLUSIONS: In a large-scale, randomized trial of United States male physicians, alternate-day use of 400 IU of vitamin E and/or daily use of 500 mg of vitamin C for 8 years had no appreciable beneficial or harmful effect on risk of incident diagnosis of AMD.


Asunto(s)
Ácido Ascórbico/administración & dosificación , Degeneración Macular/diagnóstico , Degeneración Macular/epidemiología , Vitamina E/administración & dosificación , Vitaminas/administración & dosificación , Anciano , Suplementos Dietéticos , Método Doble Ciego , Combinación de Medicamentos , Humanos , Incidencia , Masculino , Persona de Mediana Edad , Médicos , Factores de Riesgo , Encuestas y Cuestionarios , Estados Unidos/epidemiología , Agudeza Visual/fisiología
17.
Arch Ophthalmol ; 129(7): 921-9, 2011 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-21402976

RESUMEN

OBJECTIVE: To examine whether intake of ω-3 fatty acids and fish affects incidence of age-related macular degeneration (AMD) in women. DESIGN: A detailed food-frequency questionnaire was administered at baseline among 39 876 female health professionals (mean [SD] age: 54.6 [7.0] years). A total of 38 022 women completed the questionnaire and were free of a diagnosis of AMD. The main outcome measure was incident AMD responsible for a reduction in best-corrected visual acuity to 20/30 or worse based on self-report confirmed by medical record review. RESULTS: A total of 235 cases of AMD, most characterized by some combination of drusen and retinal pigment epithelial changes, were confirmed during an average of 10 years of follow-up. Women in the highest tertile of intake for docosahexaenoic acid, compared with those in the lowest, had a multivariate-adjusted relative risk of AMD of 0.62 (95% confidence interval, 0.44-0.87). For eicosapentaenoic acid, women in the highest tertile of intake had a relative risk of 0.66 (95% confidence interval, 0.48-0.92). Consistent with the findings for docosahexaenoic acid and eicosapentaenoic acid, women who consumed 1 or more servings of fish per week, compared with those who consumed less than 1 serving per month, had a relative risk of AMD of 0.58 (95% confidence interval, 0.38-0.87). CONCLUSION: These prospective data from a large cohort of female health professionals without a diagnosis of AMD at baseline indicate that regular consumption of docosahexaenoic acid and eicosapentaenoic acid and fish was associated with a significantly decreased risk of incident AMD and may be of benefit in primary prevention of AMD.


Asunto(s)
Encuestas sobre Dietas , Dieta , Ácidos Grasos Omega-3/administración & dosificación , Degeneración Macular/epidemiología , Alimentos Marinos , Salud de la Mujer , Método Doble Ciego , Conducta Alimentaria , Femenino , Personal de Salud , Humanos , Incidencia , Degeneración Macular/etiología , Persona de Mediana Edad , Estudios Prospectivos , Medición de Riesgo , Encuestas y Cuestionarios , Estados Unidos/epidemiología , Agudeza Visual/fisiología
18.
Arch Ophthalmol ; 128(11): 1397-405, 2010 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-21060040

RESUMEN

OBJECTIVE: To test whether supplementation with alternate-day vitamin E or daily vitamin C affects the incidence of age-related cataract in a large cohort of men. METHODS: In a randomized, double-masked, placebo-controlled trial, 11,545 apparently healthy US male physicians 50 years or older without a diagnosis of cataract at baseline were randomly assigned to receive 400 IU of vitamin E or placebo on alternate days and 500 mg of vitamin C or placebo daily. MAIN OUTCOME MEASURE: Incident cataract responsible for a reduction in best-corrected visual acuity to 20/30 or worse based on self-report confirmed by medical record review. APPLICATION TO CLINICAL PRACTICE: Long-term use of vitamin E and C supplements has no appreciable effect on cataract. RESULTS: After 8 years of treatment and follow-up, 1174 incident cataracts were confirmed. There were 579 cataracts in the vitamin E-treated group and 595 in the vitamin E placebo group (hazard ratio, 0.99; 95% confidence interval, 0.88-1.11). For vitamin C, there were 593 cataracts in the treated group and 581 in the placebo group (hazard ratio, 1.02; 95% confidence interval, 0.91-1.14). CONCLUSION: Long-term alternate-day use of 400 IU of vitamin E and daily use of 500 mg of vitamin C had no notable beneficial or harmful effect on the risk of cataract. TRIAL REGISTRATION: clinicaltrials.gov Identifier: NCT00270647.


Asunto(s)
Envejecimiento/fisiología , Antioxidantes/administración & dosificación , Ácido Ascórbico/administración & dosificación , Catarata/epidemiología , Vitamina E/administración & dosificación , Anciano , Catarata/prevención & control , Extracción de Catarata/estadística & datos numéricos , Método Doble Ciego , Combinación de Medicamentos , Estudios de Seguimiento , Humanos , Incidencia , Masculino , Persona de Mediana Edad , Médicos , Medición de Riesgo , Estados Unidos/epidemiología , Agudeza Visual
19.
Arch Intern Med ; 169(4): 335-41, 2009 Feb 23.
Artículo en Inglés | MEDLINE | ID: mdl-19237716

RESUMEN

BACKGROUND: Observational epidemiologic studies indicate a direct association between homocysteine concentration in the blood and the risk of age-related macular degeneration (AMD), but randomized trial data to examine the effect of therapy to lower homocysteine levels in AMD are lacking. Our objective was to examine the incidence of AMD in a trial of combined folic acid, pyridoxine hydrochloride (vitamin B(6)), and cyanocobalamin (vitamin B(12)) therapy. METHODS: We conducted a randomized, double-blind, placebo-controlled trial including 5442 female health care professionals 40 years or older with preexisting cardiovascular disease or 3 or more cardiovascular disease risk factors. A total of 5205 of these women did not have a diagnosis of AMD at baseline and were included in this analysis. Participants were randomly assigned to receive a combination of folic acid (2.5 mg/d), pyridoxine hydrochloride (50 mg/d), and cyanocobalamin (1 mg/d) or placebo. Our main outcome measures included total AMD, defined as a self-report documented by medical record evidence of an initial diagnosis after randomization, and visually significant AMD, defined as confirmed incident AMD with visual acuity of 20/30 or worse attributable to this condition. RESULTS: After an average of 7.3 years of treatment and follow-up, there were 55 cases of AMD in the combination treatment group and 82 in the placebo group (relative risk, 0.66; 95% confidence interval, 0.47-0.93 [P = .02]). For visually significant AMD, there were 26 cases in the combination treatment group and 44 in the placebo group (relative risk, 0.59; 95% confidence interval, 0.36-0.95 [P = .03]). CONCLUSIONS: These randomized trial data from a large cohort of women at high risk of cardiovascular disease indicate that daily supplementation with folic acid, pyridoxine, and cyanocobalamin may reduce the risk of AMD.


Asunto(s)
Enfermedades Cardiovasculares/prevención & control , Ácido Fólico/uso terapéutico , Degeneración Macular/tratamiento farmacológico , Degeneración Macular/prevención & control , Piridoxina/uso terapéutico , Vitamina B 12/uso terapéutico , Complejo Vitamínico B/uso terapéutico , Adulto , Anciano , Enfermedades Cardiovasculares/complicaciones , Método Doble Ciego , Quimioterapia Combinada , Determinación de Punto Final , Femenino , Estudios de Seguimiento , Humanos , Incidencia , Degeneración Macular/complicaciones , Persona de Mediana Edad , Modelos de Riesgos Proporcionales , Factores de Riesgo , Resultado del Tratamiento
20.
JAMA ; 301(1): 52-62, 2009 Jan 07.
Artículo en Inglés | MEDLINE | ID: mdl-19066368

RESUMEN

CONTEXT: Many individuals take vitamins in the hopes of preventing chronic diseases such as cancer, and vitamins E and C are among the most common individual supplements. A large-scale randomized trial suggested that vitamin E may reduce risk of prostate cancer; however, few trials have been powered to address this relationship. No previous trial in men at usual risk has examined vitamin C alone in the prevention of cancer. OBJECTIVE: To evaluate whether long-term vitamin E or C supplementation decreases risk of prostate and total cancer events among men. DESIGN, SETTING, AND PARTICIPANTS: The Physicians' Health Study II is a randomized, double-blind, placebo-controlled factorial trial of vitamins E and C that began in 1997 and continued until its scheduled completion on August 31, 2007. A total of 14,641 male physicians in the United States initially aged 50 years or older, including 1307 men with a history of prior cancer at randomization, were enrolled. INTERVENTION: Individual supplements of 400 IU of vitamin E every other day and 500 mg of vitamin C daily. MAIN OUTCOME MEASURES: Prostate and total cancer. RESULTS: During a mean follow-up of 8.0 years, there were 1008 confirmed incident cases of prostate cancer and 1943 total cancers. Compared with placebo, vitamin E had no effect on the incidence of prostate cancer (active and placebo vitamin E groups, 9.1 and 9.5 events per 1000 person-years; hazard ratio [HR], 0.97; 95% confidence interval [CI], 0.85-1.09; P = .58) or total cancer (active and placebo vitamin E groups, 17.8 and 17.3 cases per 1000 person-years; HR, 1.04; 95% CI, 0.95-1.13; P = .41). There was also no significant effect of vitamin C on total cancer (active and placebo vitamin C groups, 17.6 and 17.5 events per 1000 person-years; HR, 1.01; 95% CI, 0.92-1.10; P = .86) or prostate cancer (active and placebo vitamin C groups, 9.4 and 9.2 cases per 1000 person-years; HR, 1.02; 95% CI, 0.90-1.15; P = .80). Neither vitamin E nor vitamin C had a significant effect on colorectal, lung, or other site-specific cancers. Adjustment for adherence and exclusion of the first 4 or 6 years of follow-up did not alter the results. Stratification by various cancer risk factors demonstrated no significant modification of the effect of vitamin E on prostate cancer risk or either agent on total cancer risk. CONCLUSIONS: In this large, long-term trial of male physicians, neither vitamin E nor C supplementation reduced the risk of prostate or total cancer. These data provide no support for the use of these supplements for the prevention of cancer in middle-aged and older men. TRIAL REGISTRATION: clinicaltrials.gov Identifier: NCT00270647.


Asunto(s)
Antioxidantes/uso terapéutico , Ácido Ascórbico/uso terapéutico , Suplementos Dietéticos , Neoplasias/prevención & control , Neoplasias de la Próstata/prevención & control , Vitamina E/uso terapéutico , Anciano , Método Doble Ciego , Humanos , Estudios Longitudinales , Masculino , Persona de Mediana Edad , Neoplasias/epidemiología , Neoplasias de la Próstata/epidemiología , Resultado del Tratamiento , alfa-Tocoferol/uso terapéutico
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