RESUMO
BACKGROUND & AIMS: Colorectal cancer (CRC) deaths occur when patients do not receive screening or have inadequate follow-up of abnormal results or when the screening test fails. We have few data on the contribution of each to CRC-associated deaths or factors associated with these events. METHODS: We performed a retrospective cohort study of patients in the Kaiser Permanente Northern and Southern California systems (55-90 years old) who died of CRC from 2006 through 2012 and had ≥5 years of enrollment before diagnosis. We compared data from patients with those from a matched cohort of cancer-free patients in the same system. Receipt, results, indications, and follow-up of CRC tests in the 10-year period before diagnosis were obtained from electronic databases and chart audits. RESULTS: Of 1750 CRC deaths, 75.9% (n = 1328) occurred in patients who were not up to date in screening and 24.1% (n = 422) occurred in patients who were up to date. Failure to screen was associated with fewer visits to primary care physicians. Of 3486 cancer-free patients, 44.6% were up to date in their screening. Patients who were up to date in their screening had a lower risk of CRC death (odds ratio, 0.38; 95% confidence interval, 0.33-0.44). Failure to screen, or failure to screen at appropriate intervals, occurred in a 67.8% of patients who died of CRC vs 53.2% of cancer-free patients; failure to follow-up on abnormal results occurred in 8.1% of patients who died of CRC vs 2.2% of cancer-free patients. CRC death was associated with higher odds of failure to screen or failure to screen at appropriate intervals (odds ratio, 2.40; 95% confidence interval, 2.07-2.77) and failure to follow-up on abnormal results (odds ratio, 7.26; 95% confidence interval, 5.26-10.03). CONCLUSIONS: Being up to date on screening substantially decreases the risk of CRC death. In 2 health care systems with high rates of screening, most people who died of CRC had failures in the screening process that could be rectified, such as failure to follow-up on abnormal findings; these significantly increased the risk for CRC death.
Assuntos
Adenocarcinoma/diagnóstico , Adenocarcinoma/mortalidade , Neoplasias Colorretais/diagnóstico , Neoplasias Colorretais/mortalidade , Detecção Precoce de Câncer/mortalidade , Adenocarcinoma/prevenção & controle , Idoso , Idoso de 80 Anos ou mais , California/epidemiologia , Causas de Morte , Neoplasias Colorretais/prevenção & controle , Detecção Precoce de Câncer/efeitos adversos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Aceitação pelo Paciente de Cuidados de Saúde , Valor Preditivo dos Testes , Fatores de Proteção , Reprodutibilidade dos Testes , Estudos Retrospectivos , Fatores de Risco , Fatores de TempoRESUMO
OBJECTIVE: Screening colonoscopy's effectiveness in reducing colorectal cancer mortality risk in community populations is unclear, particularly for right-colon cancers, leading to recommendations against its use for screening in some countries. This study aimed to determine whether, among average-risk people, receipt of screening colonoscopy reduces the risk of dying from both right-colon and left-colon/rectal cancers. DESIGN: We conducted a nested case-control study with incidence-density matching in screening-eligible Kaiser Permanente members. Patients who were 55-90â years old on their colorectal cancer death date during 2006-2012 were matched on diagnosis (reference) date to controls on age, sex, health plan enrolment duration and geographical region. We excluded patients at increased colorectal cancer risk, or with prior colorectal cancer diagnosis or colectomy. The association between screening colonoscopy receipt in the 10-year period before the reference date and colorectal cancer death risk was evaluated while accounting for other screening exposures. RESULTS: We analysed 1747 patients who died from colorectal cancer and 3460 colorectal cancer-free controls. Compared with no endoscopic screening, receipt of a screening colonoscopy was associated with a 67% reduction in the risk of death from any colorectal cancer (adjusted OR (aOR)=0.33, 95% CI 0.21 to 0.52). By cancer location, screening colonoscopy was associated with a 65% reduction in risk of death for right-colon cancers (aOR=0.35, CI 0.18 to 0.65) and a 75% reduction for left-colon/rectal cancers (aOR=0.25, CI 0.12 to 0.53). CONCLUSIONS: Screening colonoscopy was associated with a substantial and comparably decreased mortality risk for both right-sided and left-sided cancers within a large community-based population.
Assuntos
Neoplasias do Colo/mortalidade , Colonoscopia/estatística & dados numéricos , Detecção Precoce de Câncer/estatística & dados numéricos , Neoplasias Retais/mortalidade , Idoso , Idoso de 80 Anos ou mais , California/epidemiologia , Estudos de Casos e Controles , Colo Ascendente , Colo Descendente , Colo Sigmoide , Colo Transverso , Neoplasias do Colo/diagnóstico por imagem , Neoplasias do Colo/patologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias Retais/diagnóstico por imagem , Neoplasias Retais/patologia , Fatores de Risco , Sigmoidoscopia/estatística & dados numéricosRESUMO
BACKGROUND: Screening outreach programs using population health management principles offer services uniformly to all eligible persons, but racial/ethnic colorectal cancer (CRC) screening patterns in such programs are not well known. OBJECTIVE: To examine the association between race/ethnicity and the receipt of CRC screening and timely follow-up of positive results before and after implementation of a screening program. DESIGN: Retrospective cohort study of screen-eligible individuals at the Kaiser Permanente Northern California community-based integrated healthcare delivery system (2004-2013). SUBJECTS: A total of 868,934 screen-eligible individuals 51-74 years of age at cohort entry, which included 662,872 persons in the period before program implementation (2004-2006), 654,633 during the first 3 years after implementation (2007-2009), and 665,268 in the period from 4 to 7 years (2010-2013) after program implementation. INTERVENTION: A comprehensive system-wide long-term effort to increase CRC that included leadership alignment, goal-setting, and quality assurance through a PHM approach, using mailed fecal immunochemical testing (FIT) along with offering screening at office visits. MAIN MEASURES: Differences over time and by race/ethnicity in up-to-date CRC screening (overall and by test type) and timely follow-up of a positive screen. Race/ethnicity categories included non-Hispanic white, non-Hispanic black, Hispanic/Latino, Asian/Pacific Islander, Native American, and multiple races. KEY RESULTS: From 2004 to 2013, age/sex-adjusted CRC screening rates increased in all groups, including 35.2 to 81.1 % among whites and 35.6 to 78.0 % among blacks. Screening rates among Hispanics (33.1 to 78.3 %) and Native Americans (29.4 to 74.5 %) remained lower than those for whites both before and after program implementation. Blacks, who had slightly higher rates before program implementation (adjusted rate ratio [RR] = 1.04, 99 % CI: 1.02-1.05), had lower rates after program implementation (RR for period from 4 to 7 years = 0.97, 99 % CI: 0.96-0.97). There were also substantial improvements in timely follow-up of positive screening results. CONCLUSIONS: In this screening program using core PHM principles, CRC screening increased markedly in all racial/ethnic groups, but disparities persisted for some groups and developed in others, which correlated with levels of adoption of mailed FIT.
Assuntos
Neoplasias Colorretais/diagnóstico , Neoplasias Colorretais/etnologia , Serviços de Saúde Comunitária/métodos , Gerenciamento Clínico , Detecção Precoce de Câncer/métodos , Saúde da População , Idoso , Estudos de Coortes , Colonoscopia/métodos , Neoplasias Colorretais/prevenção & controle , Etnicidade , Feminino , Seguimentos , Acessibilidade aos Serviços de Saúde , Humanos , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Grupos Raciais/etnologia , Estudos Retrospectivos , Sigmoidoscopia/métodosRESUMO
BACKGROUND: The effectiveness of screening colonoscopy in average-risk adults is uncertain, particularly for right colon cancer. OBJECTIVE: To examine the association between screening colonoscopy and risk for incident late-stage colorectal cancer (CRC). DESIGN: Nested case-control study. SETTING: Four U.S. health plans. PATIENTS: 1039 average-risk adults enrolled for at least 5 years in one of the health plans. Case patients were aged 55 to 85 years on their diagnosis date (reference date) of stage IIB or higher (late-stage) CRC during 2006 to 2008. One or 2 control patients were selected for each case patient, matched on birth year, sex, health plan, and prior enrollment duration. MEASUREMENTS: Receipt of CRC screening 3 months to 10 years before the reference date, ascertained through medical record audits. Case patients and control patients were compared on receipt of screening colonoscopy or sigmoidoscopy by using conditional logistic regression that accounted for health history, socioeconomic status, and other screening exposures. RESULTS: In analyses restricted to 471 eligible case patients and their 509 matched control patients, 13 case patients (2.8%) and 46 control patients (9.0%) had undergone screening colonoscopy, which corresponded to an adjusted odds ratio (AOR) of 0.29 (95% CI, 0.15 to 0.58) for any late-stage CRC, 0.36 (CI, 0.16 to 0.80) for right colon cancer, and 0.26 (CI, 0.06 to 1.11; P = 0.069) for left colon/rectum cancer. Ninety-two case patients (19.5%) and 173 control patients (34.0%) had screening sigmoidoscopy, corresponding to an AOR of 0.50 (CI, 0.36 to 0.70) overall, 0.79 (CI, 0.51 to 1.23) for right colon late-stage cancer, and 0.26 (CI, 0.14 to 0.48) for left colon cancer. LIMITATION: The small number of screening colonoscopies affected the precision of the estimates. CONCLUSION: Screening with colonoscopy in average-risk persons was associated with reduced risk for diagnosis of incident late-stage CRC, including right-sided colon cancer. For sigmoidoscopy, this association was seen for left CRC, but the association for right colon late-stage cancer was not statistically significant.
Assuntos
Colonoscopia , Neoplasias Colorretais/diagnóstico , Detecção Precoce de Câncer , Programas de Rastreamento , Idoso , Idoso de 80 Anos ou mais , Estudos de Casos e Controles , Colonoscopia/economia , Neoplasias Colorretais/patologia , Neoplasias Colorretais/prevenção & controle , Detecção Precoce de Câncer/economia , Feminino , Humanos , Modelos Logísticos , Masculino , Programas de Rastreamento/economia , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Fatores de Risco , Sensibilidade e Especificidade , SigmoidoscopiaRESUMO
Importance: The fecal immunochemical test (FIT) is widely used for colorectal cancer (CRC) screening, but evidence of its effectiveness is limited. Objective: To evaluate whether FIT screening is associated with a lower risk of dying from CRC overall, according to cancer location, and within demographic groups. Design, Setting, and Participants: This nested case-control study in a cohort of screening-eligible people was conducted in 2 large, integrated health systems of racially, ethnically, and socioeconomically diverse members with long-term programs of mailed FIT screening outreach. Eligible participants included people aged 52 to 85 years who died from colorectal adenocarcinoma between 2011 and 2017 (cases); cases were matched in a 1:8 ratio based on age, sex, health-plan membership duration, and geographic area to randomly selected persons who were alive and CRC-free on case's diagnosis date (controls). Data analysis was conducted from January 2002 to December 2017. Exposures: Completing 1 or more FIT screenings in the 5-year period prior to the CRC diagnosis date among cases or the corresponding date among controls; in secondary analyses, 2- to 10-year intervals were evaluated. Main Outcomes and Measures: The primary study outcome was CRC death overall and by tumor location. Secondary analyses were performed to assess CRC death by race and ethnicity. Results: From a cohort of 2â¯127â¯128 people, a total of 10â¯711 participants (3529 aged 60-69 years [32.9%]; 5587 male [52.1%] and 5124 female [47.8%]; 1254 non-Hispanic Asian [11.7%]; 973 non-Hispanic Black [9.1%]; 1929 Hispanic or Latino [18.0%]; 6345 non-Hispanic White [59.2%]) was identified, including 1103 cases and 9608 controls. Among controls during the 10-year period prior to the reference date, 6101 (63.5%) completed 1 or more FITs with a cumulative 12.6% positivity rate (768 controls), of whom 610 (79.4%) had a colonoscopy within 1 year. During the 5-year period, 494 cases (44.8%) and 5345 controls (55.6%) completed 1 or more FITs. In regression analysis, completing 1 or more FIT screening was associated with a 33% lower risk of death from CRC (adjusted odds ratio [aOR], 0.67; 95% CI, 0.59-0.76) and 42% lower risk in the left colon and rectum (aOR, 0.58; 95% CI, 0.48-0.71). There was no association with right colon cancers (aOR, 0.83; 95% CI, 0.69-1.01) but the difference in the estimates between the right colon and left colon or rectum was statistically significant (P = .01). FIT screening was associated with lower CRC mortality risk among non-Hispanic Asian (aOR, 0.37; 95% CI, 0.23-0.59), non-Hispanic Black (aOR, 0.58; 95% CI, 0.39-0.85) and non-Hispanic White individuals (aOR, 0.70; 95% CI, 0.57-0.86) (P for homogeneity = .04 for homogeneity). Conclusions and Relevance: In this nested case-control study, completing FIT was associated with a lower risk of overall death from CRC, particularly in the left colon, and the associations were observed across racial and ethnic groups. These findings support the use of FIT in population-based screening strategies.
Assuntos
Neoplasias Colorretais , Detecção Precoce de Câncer , Sangue Oculto , Humanos , Neoplasias Colorretais/diagnóstico , Neoplasias Colorretais/mortalidade , Masculino , Idoso , Feminino , Pessoa de Meia-Idade , Estudos de Casos e Controles , Detecção Precoce de Câncer/métodos , Idoso de 80 Anos ou mais , Programas de Rastreamento/métodos , Fezes/químicaAssuntos
Aspirina , Neoplasias Colorretais , Anti-Inflamatórios não Esteroides , Humanos , Incidência , RiscoRESUMO
OBJECTIVE: To examine whether receiving a fecal occult blood test after a negative sigmoidoscopy reduced mortality from colorectal cancer. METHODS: We used a nested case-control design with incidence-density matching in historical cohorts of 1,877,740 50-90-year-old persons during 2006-2012, in an integrated health-system setting. We selected 1758 average risk patients who died from colorectal cancer and 3503 matched colorectal cancer-free persons. Colorectal cancer-specific death was ascertained from cancer and mortality registries. Screening histories were determined from electronic and chart-audit clinical data in the 5- to 10-year period prior to the reference date. We evaluated receipt of subsequent fecal occult blood test within five years of the reference date among patients with negative sigmoidoscopy two to six years before the reference date. RESULTS: Of the 5261 patients, 831 patients (204 colorectal cancer deaths/627 controls) had either negative sigmoidoscopy only (n = 592) or negative sigmoidoscopy with subsequent screening fecal occult blood test (n = 239). Fifty-six (27.5%) of the 204 patients dying of colorectal cancer and 183 (29.2%) of the 627 colorectal cancer-free patients received fecal occult blood test following a negative sigmoidoscopy. Conditional regressions found no significant association between fecal occult blood test receipt and colorectal cancer death risk, overall (adjusted odds ratio = 0.93, confidence interval: 0.65-1.33), or for right (odds ratio = 1.02, confidence interval: 0.65-1.60) or left-colon/rectum (odds ratio = 0.77, confidence interval: 0.39-1.52) cancers. Similar results were obtained in sensitivity analyses with alternative exposure ascertainment windows or timing of fecal occult blood test. CONCLUSIONS: Our results suggest that receipt of at least one fecal occult blood test during the several years after a negative sigmoidoscopy did not substantially reduce mortality from colorectal cancer.
Assuntos
Neoplasias Colorretais , Sigmoidoscopia , Estudos de Casos e Controles , Colonoscopia , Neoplasias Colorretais/diagnóstico , Humanos , Programas de Rastreamento , Sangue OcultoRESUMO
BACKGROUND: Prior research suggests that older patients are less likely to undergo resection of early-stage non-small-cell lung carcinomas (NSCLCs). We surveyed surgeons to understand how their recommendations for lobectomy were influenced by age, the presence and severity of smoking-related lung disease, or by characteristics of the surgeons and their practices. METHODS: We surveyed surgeons caring for NSCLC patients regarding whether they would recommend lobectomy for hypothetical patients with early-stage NSCLC who varied by age (55 vs. 80 years) and comorbid illness (none, moderate, severe chronic obstructive pulmonary disease [COPD]). Ordinal logistic regression was used to identify the importance of patient, surgeon, and practice characteristics on surgery recommendations. RESULTS: Surgeons recommended lobectomy for nearly all patients who were 55 years old with no comorbidity (adjusted proportion 98.6%), 55 years old with moderate COPD (adjusted proportion 97.8%), or 80 years old with no comorbidity (adjusted proportion 98.1%). Fewer recommended lobectomy for 80-year-old patients with moderate COPD (adjusted proportion 82.3%), and far fewer recommended lobectomy for severe COPD, irrespective of age (adjusted rate 18.7% for the 55-year-old patient and 6.1% for the 80-year-old patient) (P < 0.002). Surgeons who enroll patients onto clinical trials (P = 0.03) were more likely than others to recommend lobectomy, but no other surgeon characteristic predicted recommendations. CONCLUSIONS: Lower rates of lobectomy among older patients do not seem to be explained by age-related biases among surgeons for otherwise healthy patients.
Assuntos
Carcinoma Pulmonar de Células não Pequenas/cirurgia , Neoplasias Pulmonares/cirurgia , Pneumonectomia , Padrões de Prática Médica/estatística & dados numéricos , Adulto , Fatores Etários , Algoritmos , Boston/epidemiologia , Carcinoma Pulmonar de Células não Pequenas/patologia , Comorbidade , Tomada de Decisões , Feminino , Cirurgia Geral/estatística & dados numéricos , Pesquisas sobre Atenção à Saúde , Humanos , Modelos Logísticos , Neoplasias Pulmonares/patologia , Masculino , Pessoa de Meia-Idade , Pneumonectomia/estatística & dados numéricos , Guias de Prática Clínica como Assunto , Doença Pulmonar Obstrutiva Crônica/complicações , Doença Pulmonar Obstrutiva Crônica/epidemiologia , Análise de Regressão , Fatores de Risco , Índice de Gravidade de Doença , Fumar/efeitos adversos , Fumar/epidemiologia , Inquéritos e Questionários , Cirurgia Torácica/estatística & dados numéricosRESUMO
Primary care clinicians initiate and oversee colorectal screening for their patients, but colonoscopy, a central component of screening programs, is usually performed by consultants. The accuracy and safety of colonoscopy varies among endoscopists, even those with mainstream training and certification. Therefore, it is a primary care responsibility to choose the best available colonoscopy services. A working group of the National Colorectal Cancer Roundtable identified a set of indicators that primary care clinicians can use to assess the quality of colonoscopy services. Quality measures are of actual performance, not training, specialty, or experience alone. The main elements of quality are a complete report, technical competence, and a safe setting for the procedure. We provide explicit criteria that primary care physicians can use when choosing a colonoscopist. Information on quality indicators will be increasingly available with quality improvement efforts within the colonoscopy community and growth in the use of electronic medical records.
Assuntos
Colonoscopia/normas , Conferências de Consenso como Assunto , Médicos/normas , Biópsia/normas , Seguimentos , Humanos , Garantia da Qualidade dos Cuidados de Saúde , Encaminhamento e Consulta/normas , Responsabilidade SocialRESUMO
PURPOSE: Colorectal cancer (CRC) screening remains underutilized. The objective of this study was to examine the impact of primary care and economic barriers to health care on CRC testing relative to the 2001 Medicare expansion of screening coverage. METHODS: Medicare Current Beneficiary Survey data were use to study community-dwelling enrollees aged 65 to 80 years, free of renal disease and CRC, and who participated in the survey in 2000 (n = 8,330), 2003 (n = 7,889), or 2005 (n = 7,614). Three outcomes were examined: colonoscopy/sigmoidoscopy within 5 years (recent endoscopy), endoscopy more than 5 years previously, and fecal occult blood test (FOBT) within 2 years. RESULTS: Endoscopy use increased and FOBT use decreased during the 6-year period, with no significant independent differences between those receiving care from primary care physicians and those receiving care from other physicians. Beneficiaries without a usual place of health care were the least likely to undergo CRC testing, and that gap widened with time: adjusted odds ratio (AOR) = 0.27 (95% confidence interval [CI], 0.19-0.39) for FOBT, and AOR = 0.35 (95% CI, 0.27-0.46) for endoscopy in 2000 compared with AOR = 0.18 (95% CI, 0.11-0.30) for FOBT and AOR = 0.22 (95% CI, 0.17-0.30) for endoscopy in 2005. Disparities in use of recent endoscopy by type of health insurance coverage in both 2000 and 2005 were greater for enrollees with a high school education or higher than they were for less-educated enrollees. There were no statistically significant differences by delayed care due to cost after adjustment for health insurance. CONCLUSION: Despite expanding coverage for screening, complex CRC screening disparities persisted based on differences in the usual place and cost of health care, type of health insurance coverage, and level of education.
Assuntos
Neoplasias Colorretais/diagnóstico , Detecção Precoce de Câncer/estatística & dados numéricos , Acessibilidade aos Serviços de Saúde/estatística & dados numéricos , Cobertura do Seguro/estatística & dados numéricos , Medicare/estatística & dados numéricos , Atenção Primária à Saúde/estatística & dados numéricos , Idoso , Idoso de 80 Anos ou mais , Colonoscopia/estatística & dados numéricos , Intervalos de Confiança , Estudos Transversais , Feminino , Acessibilidade aos Serviços de Saúde/economia , Disparidades nos Níveis de Saúde , Inquéritos Epidemiológicos , Humanos , Masculino , Análise Multivariada , Sangue Oculto , Razão de Chances , Padrões de Prática Médica/estatística & dados numéricos , Atenção Primária à Saúde/economia , Sigmoidoscopia/estatística & dados numéricos , Estados UnidosRESUMO
BACKGROUND AND AIMS: The goals of this study are to evaluate determinants of the time in the medical system until a colorectal cancer diagnosis and to explore characteristics associated with stage at diagnosis. METHODS: We examined medical records and survey data for 468 patients with colorectal cancer at 15 Veterans Affairs medical centers. Patients were classified as screen-detected, bleeding-detected, or other (resulting from the evaluation of another medical concern). Patients who presented emergently with obstruction or perforation were excluded. We used Cox proportional hazards models to determine predictors of time in the medical system until diagnosis. Logistic regression models were used to determine predictors of stage at diagnosis. RESULTS: We excluded 21 subjects who presented emergently, leaving 447 subjects; the mean age was 67 years and 98% were male, 66% Caucasian, and 43% stage I or II. Diagnosis was by screening for 39%, bleeding symptoms for 27%, and other for 34%. The median times to diagnosis were 73-91 days and were not significantly different by diagnostic category. In the multivariable model for time to diagnosis, older age, having comorbidities, and Atlantic region were associated with a longer time to diagnosis. In the multivariable model for stage-at-diagnosis, only the diagnostic category was associated with stage; the screen-detected category was associated with decreased risk of late-stage cancer. CONCLUSIONS: Our results point to several factors associated with a longer time from the initial clinical event until diagnosis. This increased time in the health care system did not clearly translate into more advanced disease at diagnosis.
Assuntos
Neoplasias Colorretais/diagnóstico , Garantia da Qualidade dos Cuidados de Saúde , Idoso , Neoplasias Colorretais/epidemiologia , Feminino , Humanos , Modelos Logísticos , Masculino , Vigilância da População , Modelos de Riscos Proporcionais , Fatores de Tempo , Estados Unidos/epidemiologia , United States Department of Veterans AffairsRESUMO
CONTEXT: Randomized trials suggest adjuvant chemotherapy is effective for older patients with stage III colon cancer. However, older patients are less likely to receive this therapy than younger patients, perhaps because of concern about adverse effects. OBJECTIVE: To evaluate adjuvant chemotherapy use and outcomes for older patients with stage III colon cancer from well-defined population-based settings and health care systems. DESIGN: Observational study of adjuvant chemotherapy use and outcomes by age using Poisson regression to estimate the number of adverse events adjusted for demographic and clinical factors, including comorbid illness and specific elements of chemotherapy regimens documented with clinically detailed medical record reviews and patient and surrogate surveys. SETTING: Five geographically defined regions (Alabama, Iowa, Los Angeles County, northern California, and North Carolina), 5 integrated health care delivery systems, and 15 Veterans Affairs hospitals. PATIENTS: Six hundred seventy-five patients diagnosed with stage III colon cancer from 2003 through 2005 who underwent surgical resection and were followed up for as long as 15 months postdiagnosis. MAIN OUTCOME MEASURES: Chemotherapy regimen, dose, duration, and annualized mean number of adverse events stratified by age. RESULTS: Of 202 patients aged 75 years and older, 101 (50%) received adjuvant chemotherapy compared with 87% of 473 younger patients (difference, 37%; 95% confidence interval [CI], 30%-45%). Among patients who received adjuvant chemotherapy, 14 patients (14%) aged 75 years and older and 178 younger patients (44%) received a regimen containing oxaliplatin (difference, 30%; 95% CI, 21%-38%). Older patients were less likely to continue treatment, such that by 150 days, 99 patients (40%) aged 65 years and older and 68 younger patients (25%) had discontinued chemotherapy (difference, 15%; 95% CI, 7%-23%). Overall, 162 patients (24%) had at least 1 adverse clinical event, with more events among patients treated with vs without adjuvant chemotherapy (mean, 0.39 vs 0.16; difference, 0.23; 95% CI, 0.11-0.36; P < .001). Among patients receiving adjuvant chemotherapy, adjusted rates of late clinical adverse events were lower for patients 75 years and older (mean, 0.28) vs for younger patients (0.35 for ages 18-54 years, 0.52 for ages 55-64 years, and 0.45 for ages 65-74 years; P = .008 for any age effect). CONCLUSION: Among patients with stage III colon cancer who underwent surgical resection and received adjuvant chemotherapy, older patients in the community received less-toxic and shorter chemotherapy regimens, and those treated had fewer adverse events than younger patients.