RESUMEN
OBJECTIVES: In a previous analysis of data from a French population-based case-control study (the Investigation of occupational and environmental CAuses of REspiratory cancers (ICARE) study), 'having ever worked' in wood-related occupations was associated with excess lung cancer risk after adjusting for smoking but not for occupational factors. The present study aimed to investigate the relationship between lung cancer risk and wood dust exposure after adjusting for occupational exposures. METHODS: Data were obtained from 2276 cases and 2780 controls on smoking habits and lifelong occupational history, using a standardised questionnaire with a job-specific questionnaire for wood dust exposure. Logistic regression models were used to calculate ORs and 95% CIs adjusted for age, area of residence, tobacco smoking, the number of job periods and exposure to silica, asbestos and diesel motor exhaust (DME). RESULTS: No significant association was found between lung cancer and wood dust exposure after adjustment for smoking, asbestos, silica and DME exposures. The risk of lung cancer was slightly increased among those who were exposed to wood dust more than 10 years, and had over 40 years since the first exposure. CONCLUSION: Our findings do not provide a strong support to the hypothesis that wood dust exposure is a risk factor for lung cancer. This study showed the importance of taking into account smoking and occupational coexposures in studies on lung cancer and wood dust exposure. Further studies evaluating the level and frequency of exposure during various tasks in woodwork are needed.
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Polvo/análisis , Exposición por Inhalación/efectos adversos , Neoplasias Pulmonares/etiología , Enfermedades Profesionales/etiología , Exposición Profesional/efectos adversos , Madera , Adolescente , Adulto , Anciano , Estudios de Casos y Controles , Femenino , Francia/epidemiología , Humanos , Neoplasias Pulmonares/epidemiología , Masculino , Persona de Mediana Edad , Enfermedades Profesionales/epidemiología , Riesgo , Encuestas y Cuestionarios , Factores de TiempoRESUMEN
OBJECTIVES: We investigated the relationship between lung cancer and occupational exposure to welding activity in ICARE, a population-based case-control study. METHODS: Analyses were restricted to men (2276 cases, 2780 controls). Welding exposure was assessed through detailed questionnaires, including lifelong occupational history. ORs were computed using unconditional logistic regression, adjusted for lifelong cigarette smoking and occupational exposure to asbestos. RESULTS: Among the regular welders, welding was associated with a risk of lung cancer (OR=1.7, 95% CI 1.1 to 2.5), which increased with the duration (OR=2.0, 95% CI 1.0 to 3.9 when duration >10 years), and was maximum 10-20 years since last welding. The risk was more pronounced in case of gas welding (OR=2.0, 95% CI 1.2 to 3.3), when the workpiece was covered by paint, grease, or other substances (OR=2.0, 95% CI 1.2 to 3.4) and when it was cleaned with chemical substances before welding. No statistically significant increase in lung cancer risk was observed among occasional welders. CONCLUSIONS: Although these results should be confirmed, we showed that type of welding and mode of workpiece preparation are important determinants of the lung cancer risk in regular welders.
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Contaminantes Ocupacionales del Aire/efectos adversos , Neoplasias Pulmonares/etiología , Enfermedades Profesionales/etiología , Exposición Profesional/efectos adversos , Soldadura , Trabajo , Anciano , Estudios de Casos y Controles , Gases , Humanos , Modelos Logísticos , Masculino , Persona de Mediana Edad , Ocupaciones , Oportunidad Relativa , Pintura , Factores de Riesgo , Encuestas y CuestionariosRESUMEN
OBJECTIVE: The objective of the study was to investigate the joint effect of occupational exposure to asbestos, and tobacco and alcohol consumption, on the risk of laryngeal cancer among men. METHODS: We used data from a large population-based case-control study conducted in France. We estimated two-way and three-way interactions between asbestos exposure (never vs ever exposed), tobacco consumption (<20 vs. ≥20 pack-years) and alcohol consumption (<5 vs. ≥5 drinks per day). The interaction on an additive scale was assessed by estimating the relative excess risk due to interaction (RERI) and the attributable proportion due to interaction, and the interaction on a multiplicative scale was assessed by estimating the multiplicative interaction parameter (ψ). Multiplicative interactions were also assessed using fractional polynomials for alcohol drinking, tobacco smoking and asbestos exposure. RESULTS: When compared with light-to-moderate smokers and drinkers never exposed to asbestos, the increase in laryngeal cancer risk was smallest among light-to-moderate drinkers and smokers exposed to asbestos (OR=2.23 (1.08 to 4.60)), and highest among heavy smokers and drinkers ever exposed to asbestos (OR=69.39 (35.54 to 135.5)). We found an additive joint effect between asbestos exposure and alcohol consumption (RERI=4.75 (-4.29 to 11.12)), whereas we observed a more than additive joint effect between asbestos exposure and tobacco consumption (RERI=8.50 (0.71 to 23.81)), as well as between asbestos exposure, and tobacco and alcohol consumption (RERI=26.57 (11.52 to 67.88)). However, our results did not suggest any interaction on a multiplicative scale. CONCLUSIONS: Our results suggest that asbestos exposure, in combination with tobacco and alcohol exposure, accounted for a substantial number of laryngeal cancer cases. Our findings therefore highlight the need for prevention in activities, such as construction work, where exposure to asbestos-containing materials remains.
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Consumo de Bebidas Alcohólicas/efectos adversos , Amianto/efectos adversos , Etanol/efectos adversos , Neoplasias Laríngeas/etiología , Nicotiana/efectos adversos , Exposición Profesional/efectos adversos , Fumar/efectos adversos , Alcoholismo , Estudios de Casos y Controles , Francia , Conductas Relacionadas con la Salud , Humanos , Masculino , Persona de Mediana Edad , Enfermedades Profesionales/etiología , Oportunidad Relativa , Factores de RiesgoRESUMEN
Background. In a French large population-based case-control study we investigated the dose-response relationship between lung cancer and occupational exposure to diesel motor exhaust (DME), taking into account asbestos exposure. Methods. Exposure to DME was assessed by questionnaire. Asbestos was taken into account through a global indicator of exposure to occupational carcinogens or by a specific JEM. Results. We found a crude dose response relationship with most of the indicators of DME exposure, including with the cumulative exposure index. All results were affected by adjustment for asbestos exposure. The dose response relationships between DME and lung cancer were observed among subjects never exposed to asbestos. Conclusions. Exposure to DME and to asbestos is frequently found among the same subjects, which may explain why dose-response relationships in previous studies that adjusted for asbestos exposure were inconsistent.
RESUMEN
BACKGROUND: Few occupational studies have addressed head and neck cancer, and these studies have been predominantly conducted in men. Accordingly, our objective was to investigate the association between head and neck cancer and occupation in women. METHODS: ICARE, a French population-based case-control study, included 296 squamous cell carcinomas of the head and neck in women and 775 controls. Lifelong occupational history was collected. Odds ratios (ORs) and 95% confidence intervals (CI), adjusted for smoking, alcohol drinking and education level, were estimated for occupations and industries. RESULTS: An elevated OR was observed for working proprietors working for 10 years or more (OR = 3.83, 95% CI: 1.12-13.0) with a significant trend with duration of employment (P = 0.047). Elevated but non-significant ORs were observed for street vendors (OR = 3.76, 95% CI: 0.99-14.3, P for trend = 0.13), bakers (OR = 4.19, 95% CI: 0.63-27.9, P for trend = 0.06), and welders and flame cutters (OR = 2.18, 95% CI: 0.33-14.4, P for trend = 0.05). CONCLUSIONS: This exploratory study suggests a role of occupational exposures in the development of HN cancer in women. Further investigations of exposures to specific agents are needed.
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Neoplasias de Cabeza y Cuello/epidemiología , Enfermedades Profesionales/epidemiología , Carcinoma de Células Escamosas/epidemiología , Estudios de Casos y Controles , Femenino , Francia/epidemiología , Humanos , Carcinoma de Células Escamosas de Cabeza y CuelloRESUMEN
BACKGROUND: The aim of this study was to evaluate the role of family history of cancer and personal history of other medical conditions in the aetiology of the oral cavity cancer in France. METHODS: We used data from 689 cases of oral cavity squamous cell carcinoma and 3481 controls included in a population-based case-control study, the ICARE study. Odds-ratios (ORs) associated with family history of cancer and personal medical conditions and their 95% confidence intervals (95% CI) were estimated by unconditional logistic regression and were adjusted for age, gender, area of residence, education, body mass index, tobacco smoking and alcohol drinking. RESULTS: Personal history of oral candidiasis was related to a significantly increased risk of oral cavity cancer (OR 5.0, 95% CI 2.1-12.1). History of head and neck cancers among the first-degree relatives was associated with an OR of 1.9 (95% CI 1.2-2.8). The risk increased with the number of first-degree relatives with head and neck cancer. CONCLUSION: A family history of head and neck cancer is a marker of an increased risk of oral cavity cancer and should be taken into account to target prevention efforts and screening. Further studies are needed to clarify the association between oral cavity cancer and personal history of candidiasis.
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Carcinoma de Células Escamosas/etiología , Neoplasias de la Boca/etiología , Anciano , Consumo de Bebidas Alcohólicas/efectos adversos , Estudios de Casos y Controles , Femenino , Estudios de Seguimiento , Francia , Humanos , Masculino , Anamnesis , Persona de Mediana Edad , Sistema de Registros , Factores de Riesgo , Fumar/efectos adversosRESUMEN
OBJECTIVE: To investigate the associations between occupations and head and neck (HN) cancer risk in men. METHODS: ICARE is a French population-based case-control study on HN cancer. Analyses included 1833 cases and 2747 controls. Complete occupational history was collected. Odds ratios (ORs) were estimated for occupations and industries ever held and according to duration of employment. RESULTS: Elevated ORs, increasing with duration of employment, were observed for several occupations, including cleaners (OR = 1.7; 95% confidence interval [CI], 1.0 to 2.8), launderers (OR = 6.8; CI, 1.3 to 34.4), firefighters (OR = 3.9; CI, 1.4 to 11.2), several agricultural occupations, welders (OR = 1.9; CI, 1.3 to 2.8), structural metal preparers and erectors (OR = 2.1; CI, 1.2 to 3.7), rubber workers (OR = 2.0; CI, 1.0 to 3.9), several construction occupations, and material-handling equipment operators (OR = 1.8; CI, 1.1 to 2.9). Analyses by industry corroborated these findings. CONCLUSIONS: These results confirmed the role of occupational exposures in HN cancer.
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Neoplasias de Cabeza y Cuello/etiología , Enfermedades Profesionales/etiología , Exposición Profesional/efectos adversos , Ocupaciones , Adulto , Anciano , Anciano de 80 o más Años , Estudios de Casos y Controles , Francia , Humanos , Industrias , Entrevistas como Asunto , Modelos Logísticos , Masculino , Persona de Mediana Edad , Oportunidad Relativa , Sistema de Registros , Factores de Riesgo , Encuestas y CuestionariosRESUMEN
OBJECTIVES: To assess the risk of lung cancer associated with exposure to mineral wools (MWs), while taking into account smoking, asbestos, and crystalline silica exposures. METHODS: The analyses were restricted to men (1350 cases and 1912 controls). Lifelong occupational history was collected. MWs and asbestos exposures were assessed, using task-exposure matrices and silica exposure, a job-exposure matrix. RESULTS: We observed consistent not-significant increased risks of lung cancer of the same order of magnitude among workers exposed to high levels of MWs (odds ratio, 1.4; 95% confidence interval: 0.9 to 2.2; for highest quartile of the Cumulative Exposure Index). CONCLUSIONS: These results do not allow to draw firm conclusion about a carcinogenic effect of MWs on the lung, but they cannot exclude it. Given the high number of potentially exposed workers, it will be necessary to replicate them in a future further removed from the asbestos ban.
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Contaminantes Ocupacionales del Aire/efectos adversos , Compuestos de Calcio/efectos adversos , Neoplasias Pulmonares/inducido químicamente , Enfermedades Profesionales/inducido químicamente , Exposición Profesional/efectos adversos , Silicatos/efectos adversos , Adolescente , Adulto , Anciano , Amianto/efectos adversos , Estudios de Casos y Controles , Francia , Humanos , Modelos Logísticos , Neoplasias Pulmonares/etiología , Masculino , Persona de Mediana Edad , Enfermedades Profesionales/etiología , Exposición Profesional/estadística & datos numéricos , Factores de Riesgo , Dióxido de Silicio/efectos adversos , Fumar/efectos adversos , Encuestas y Cuestionarios , Adulto JovenRESUMEN
OBJECTIVE: The association between body mass index (BMI) and the risk of oral cavity cancer, suggested by the few available studies, is controversial because of weight loss preceding cancer diagnosis and possible confounding by tobacco and alcohol consumption. The aim of this study was to evaluate in France, a high-incidence country, the association between the risk of oral cavity cancer and body mass index at interview, 2 years before the interview and at age 30, as well as BMI change. METHODS: We used data from a population-based case-control study, the Investigation of occupational and environmental CAuses of REspiratory cancers study, with personal interviews and standardized questionnaires including 689 cases of oral cavity squamous cell carcinoma and 3,481 controls. Odds ratios (ORs) and 95% confidence intervals (95% CI) were estimated by unconditional logistic regression and were adjusted for gender, age, area of residence, education, tobacco smoking, and alcohol drinking. RESULTS: ORs were increased in underweight subjects at interview (OR 6.25, 95% CI 3.74-10.45). No association with underweight 2 years before the interview and at age 30 was found. Overweight and obesity at interview, 2 years before the interview and at age 30 were associated with decreased ORs (ranging from 0.13 to 0.60). BMI gain greater than 5% between age 30 and 2 years before the interview was inversely associated with oral cavity cancer (OR 0.42, 95% CI 0.33-0.54). These associations were stronger in men, and in smokers and drinkers. CONCLUSION: These results add further support to the existence of a reduced risk of oral cavity cancer among overweight and obese people or among people who increased their BMI in adulthood. The underlying mechanisms remain to be clarified.
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Índice de Masa Corporal , Neoplasias de la Boca/epidemiología , Anciano , Estudios de Casos y Controles , Intervalos de Confianza , Femenino , Francia , Humanos , Masculino , Persona de Mediana Edad , Sobrepeso/epidemiologíaRESUMEN
BACKGROUND: Results on the relationship between coffee and tea drinking and the risk of oral cavity cancer are contrasted. The aim of this study was to evaluate the relation between coffee and tea drinking and the risk of oral cavity cancer in France, a high incidence area. MATERIAL AND METHODS: We conducted a population based case-control study with face-to-face interviews and standardized questionnaires (the ICARE study, Investigation of occupational and environmental causes of respiratory cancers). We used data from 689 cases of oral cavity squamous cell carcinoma and 3481 controls. Odds-ratios (ORs) and 95% confidence intervals (95% CI) associated with tea and coffee consumption (quantity, duration, cumulative consumption) were estimated by unconditional logistic regression with adjustment for age, gender, area of residence, education, body mass index, tobacco smoking and alcohol drinking. RESULTS: We observed inverse associations between oral cavity cancer and tea or coffee consumption (odds ratio, 0.39; 95% CI 0.21-0.70, for the highest quartile of tea consumption, and 0.60, 95% CI 0.34-1.05, for the highest quartile of coffee consumption). Exclusive tea or coffee consumption was associated with a reduced risk of oral cavity cancer and their joint effect was multiplicative. No differences in risk between men and women or between consumers of tobacco and alcohol and non-consumers were observed. The odds ratios related to the subsites usually included in the oropharynx (soft palate and base of the tongue) did not differ significantly from that observed for the other subsites of the oral cavity. CONCLUSIONS: Tea and coffee drinking may decrease the risk of oral cavity cancer through antioxidant components which play a role in the repair of cellular damages. These findings need further investigation in prospective studies and the underlying mechanisms in humans remain to be clarified.
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Café , Neoplasias de la Boca/epidemiología , Té , Anciano , Anciano de 80 o más Años , Estudios de Casos y Controles , Femenino , Francia/epidemiología , Humanos , Masculino , Persona de Mediana Edad , Encuestas y CuestionariosRESUMEN
The objective was to examine the role of tobacco smoking and alcohol drinking in the incidence of oral cavity cancer by subsite in France, a high-incidence area. We analysed detailed data on lifelong tobacco smoking and alcohol drinking from 772 oral cavity cancer cases and 3555 controls included in a population-based case-control study, the ICARE study. Tobacco smoking increased the risk of oral cavity cancer even for the smaller quantities and durations, whereas alcohol drinking increased this risk only in heavy drinkers who were also ever smokers. The combined effect of smoking and drinking was greater than multiplicative. The floor of the mouth was the subsite that was the most affected by the harmful effects of tobacco and alcohol, whereas the gums were less susceptible. The risk associated with tobacco and alcohol consumption did not differ between intraoral cavity and subsites usually included in the oropharynx (soft palate and base of the tongue). Population-attributable risks for oral cavity cancer were 78.6% for tobacco smoking, 7.3% for alcohol drinking and 80.7% for tobacco and/or alcohol consumption. These results indicate that regular oral check-ups should be targeted at smokers and heavy drinkers, and that prevention efforts should be focused on smoking cessation.
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Consumo de Bebidas Alcohólicas/efectos adversos , Consumo de Bebidas Alcohólicas/epidemiología , Neoplasias de la Boca/diagnóstico , Neoplasias de la Boca/epidemiología , Vigilancia de la Población , Fumar/efectos adversos , Fumar/epidemiología , Anciano , Estudios de Casos y Controles , Femenino , Francia/epidemiología , Neoplasias Gingivales/diagnóstico , Neoplasias Gingivales/epidemiología , Humanos , Masculino , Persona de Mediana Edad , Neoplasias Palatinas/diagnóstico , Neoplasias Palatinas/epidemiología , Vigilancia de la Población/métodos , Factores de Riesgo , Encuestas y Cuestionarios , Neoplasias de la Lengua/diagnóstico , Neoplasias de la Lengua/epidemiologíaRESUMEN
BACKGROUND: The association between body mass index (BMI) and lung cancer is still disputed because of possible residual confounding by smoking and preclinical weight loss in case-control studies. We examined this association using data from the multicenter ICARE study in France, a large, population-based case-control study. METHODS: A total of 2,625 incident lung cancer cases and 3,381 controls were included. Weight was collected at interview, 2 years before the interview, and at age 30. Lifetime smoking exposure was calculated using the comprehensive smoking index (CSI). Adjusted odds ratios (aORs) and 95 % confidence intervals were estimated by unconditional logistic regression and controlled for age, area, education, CSI, occupational exposure, previous chronic bronchitis, and parental history of lung cancer. We also examined the role of weight change. Analyses were stratified by smoking status and sex. RESULTS: When compared with that of men with normal BMI 2 years before the interview, lung cancer aORs (95 % CI) among men with BMIs of <18.5, 25-29.9, 30-32.4, and ≥32.5 kg/m(2) were 2.7 (95 % CI 1.2-6.2), 0.9 (95 % CI 0.7-1.1), 0.8 (95 % CI 0.6-1.1), and 0.8 (95 % CI 0.6-1.0), respectively (p(trend) = 0.02). Results were more pronounced among current smokers and were similar in men and women. Weight gain over time was associated with a significant decreased risk of lung cancer. CONCLUSIONS: We found an inverse dose-dependent association between lung cancer risk and BMI 2 years prior to interview in current smokers. IMPACT STATEMENT: BMI might be an individual factor impacting the risk of lung cancer related to smoking's carcinogen-induced DNA damage.
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Índice de Masa Corporal , Neoplasias Pulmonares/epidemiología , Fumar/epidemiología , Adulto , Anciano , Peso Corporal , Estudios de Casos y Controles , Femenino , Francia/epidemiología , Humanos , Modelos Logísticos , Masculino , Persona de Mediana Edad , Vigilancia de la Población/métodos , Medición de Riesgo , Factores de RiesgoRESUMEN
OBJECTIVES: To assess the risk of lung cancer associated with occupations and industries. METHODS: A French population-based case-control study included 2923 cases and 3555 controls. Lifelong occupational history was collected. Two lists of occupations known (A) or suspected (B) to be associated with lung cancer were used. Occupations and industries not included in these lists were also explored. RESULTS: Among men, the smoking-adjusted odds ratio was 1.97 for list A (attributable fraction: 12.3%), 1.4 for list B (due especially to carpenters/joiners and transport workers). Among unlisted occupations, excess risks were found for welders, plumbers, and several construction crafts. Odds ratios among women were elevated for list A, list B (due especially to launderers/dry cleaners), cleaners and hairdressers. CONCLUSIONS: These results confirm the role of known occupations and give insight into new occupational risk factors among men and women.
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Neoplasias Pulmonares/epidemiología , Enfermedades Profesionales/epidemiología , Exposición Profesional/efectos adversos , Anciano , Contaminantes Ocupacionales del Aire/efectos adversos , Carcinógenos Ambientales/efectos adversos , Estudios de Casos y Controles , Femenino , Francia/epidemiología , Humanos , Industrias/estadística & datos numéricos , Neoplasias Pulmonares/etiología , Masculino , Persona de Mediana Edad , Enfermedades Profesionales/etiología , Ocupaciones , Oportunidad Relativa , Factores de RiesgoRESUMEN
BACKGROUND: The incidence of female lung cancer in developed countries has been increasing since 1950. In order to have recent and reliable data on the association between cigarette smoking and the risk of lung cancer in women, we analysed cases from a French population-based case-control study. METHODS: The ICARE study is a multicenter case-control study on respiratory cancers (lung and UADT cancers), set up in 10 départements that include a general cancer registry. We included 648 women lung cancer cases up to 76 years of age, with a histologically confirmed primary lung cancer. The 775 controls were randomly selected from the general population and frequency-matched with cases by age and département. RESULTS: Overall, smoking cigarettes at some time was associated with a 8-fold increase in lung cancer risk (OR=8.2, 95% CI 6.0-11.4). A dose-response relationship was observed as a function of duration, intensity and pack-years. Using restricted splines cubic models, we have shown that intensity dose-response departed significantly from linearity while the risk increased linearly with duration and decreased linearly with time since cessation. The following characteristics were associated with a higher relative risk: smoke inhalation, smoking non-filter cigarettes, smoking dark tobacco cigarettes and starting at a young age. In addition, duration, intensity and time since cessation was significantly related with histological type. This was not the case for characteristics such as the use of a filter or not, the inhalation pattern, or the type of tobacco smoked. The proportion of lung cancer cases attributable to cigarette smoking was 55% (95% CI: [47-63%]). CONCLUSIONS: Our results confirm that cigarette smoking is by far the most important cause of the current epidemic of lung cancer among French women and that the most important smoking-related variables for varying the risk of lung cancer are the duration, the intensity and the time since cessation.
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Adenocarcinoma/epidemiología , Neoplasias Pulmonares/epidemiología , Fumar , Adenocarcinoma/patología , Adenocarcinoma/fisiopatología , Adulto , Anciano , Femenino , Francia , Humanos , Incidencia , Neoplasias Pulmonares/patología , Neoplasias Pulmonares/fisiopatología , Persona de Mediana Edad , Factores de Riesgo , Cese del Hábito de FumarRESUMEN
OBJECTIVES: To determine the rate, patterns and predictors of HIV disclosure in the French Antilles and French Guiana. METHODS: A cross-sectional survey was carried out among a 15% random sample (n=398) of the hospital caseload in hospitals providing HIV care. Determinants of disclosure to a steady partner and other members of the individual's social network were analysed using logistic regression. RESULTS: From the time of diagnosis, 84.6% of those in a couple (n=173) disclosed their HIV-positive status to their steady partner, 55.6% disclosed to others, and 30.3% did not tell their status to anyone. Disclosure within a steady partnership was less likely among non-French individuals [Haitians: adjusted odds ratio (AOR) 0.11, 95% confidence interval (CI) 0.02-0.72; other nationalities: AOR 0.13, 95% CI 0.02-0.68]; and among those diagnosed with HIV after 1997 (AOR 0.21, 95% CI 0.05-0.86). Determinants of disclosure to others were found to be sex (women: AOR 2.04, 95% CI 1.24-3.36), age at diagnosis (>or=50 versus<30 years: AOR 0.42, 95% CI 0.19-0.90), nationality (Haitians versus French: AOR 0.39, 95% CI 0.19-0.77), transmission route (non-sexual versus sexual: AOR 3.38, 95% CI 1.12-10.23) and hospital inpatients (hospitalized versus non-hospitalized patients: AOR 1.98, 95% CI 1.17-3.37). After disclosing, social and emotional support from confidants was common and discrimination was infrequent. CONCLUSION: One third of PLWHA had kept their HIV status secret. Interventions targeting the general population and social institutions, and support for PLWHA by healthcare staff are needed to improve the situation.