epidemiologia estudios de cohorte

sergio.uribe@gmail.com

Estudios de cohorte

Dr Sergio Uribe

sergio.uribe@gmail.com

Diseño de estudios

● Estudios observacionales– Descriptivos

● Reporte de caso● Serie de casos● De prevalencia

– Analíticos● Casos y controles● Cohorte

– Prospectiva– retrospectiva

● Estudios experimentales

● In vitro● Animales● Clínicos

sergio.uribe@gmail.com

sergio.uribe@gmail.com

Estudios de cohorte

Población definida que se sigue para distingur características sub-grupales

Pueden o no estar expuestas

Year introduced: 1989 MeSH

sergio.uribe@gmail.com

Usos en Odontología

● Identificar factores de riesgo● Evaluar sobrevida o duración● Complicaciones● Otros outcomes

sergio.uribe@gmail.com

Estudio de cohortesEnfermos Sanos

sergio.uribe@gmail.com

Estudio de cohortesEnfermos Sanos

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sergio.uribe@gmail.com

Estudio de cohortesEnfermos Sanos

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sergio.uribe@gmail.com

Estudio de cohortesEnfermos Sanos

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RIESGORIESGORELATIVORELATIVO

----------------------

sergio.uribe@gmail.com

ejemplo

CIP Sanomamadera noc az 245 75sin mamadera noc az 50 360

sergio.uribe@gmail.com

● Results Meta-analysis of the five prospective cohort studiesprospective cohort studies (86 092 patients) found people with PD had a 1.14-fold higher risk of developing coronary heart disease (CHD) than controls [RR, 1.14; 95% confidence interval (CI), 1.07–1.21; P<0.001][RR, 1.14; 95% confidence interval (CI), 1.07–1.21; P<0.001]. Case–control studiesCase–control studies (1423 patients) showed an even greater risk of developing CHD (OR, 2.22; 95% CI, 1.59–3.117; (OR, 2.22; 95% CI, 1.59–3.117; P<0.001)P<0.001). The prevalence of CHD in the cross-sectional cross-sectional studiesstudies (17 724 patients) was significantly greater in individuals with PD than in those with no PD (OR, 1.59; 95% CI, 1.33–(OR, 1.59; 95% CI, 1.33–1.91; P<0.001)1.91; P<0.001). Analysing the relationship between number of teeth and incidence of CHD found a 1.24-fold increased risk (95% CI, 1.14–1.36; P<0.0001) of development of CHD in people who had <10 teeth.

Bahekar et al. Am Heart J 2007; 154:830–837.

The prevalence and incidence of coronary heart disease is significantly increased in periodontitis: a meta-analysis

sergio.uribe@gmail.com

● Thomson WM et alCigarette smoking and periodontal disease among 32-year-olds: a prospective study of a representative birth cohort. J Clin Periodontol. 2007 Oct;34(10):828-34.

● Broadbent JM et alProgression of dental caries and tooth loss between the third and fourth decades of life: a birth cohort study. Caries Res. 2006;40(6):459-65.

sergio.uribe@gmail.com

● Simecek JW et al.Dental sealant longevity in a cohort of young U.S. naval personnel.J Am Dent Assoc. 2005 Feb;136(2):171-8.

● Kirstilä VLongitudinal analysis of the association of human salivary antimicrobial agents with caries increment and cariogenic micro-organisms: a two-year cohort study.J Dent Res. 1998 Jan;77(1):73-80.

sergio.uribe@gmail.com

Ventajas

● relación temporal verificable● calcula incidencia● outcomes múltiples o desconocidos● < sesgo de selección que casos y controles● calcula riesgo

sergio.uribe@gmail.com

Desventajas

● costo● duración● tamaño muestral● unifactoriales● dropout

sergio.uribe@gmail.com

EstudioCasos y controles Transversales Cohortes

Población enfermos todos sanosIncidencia no no si

Prevalencia no si noAsociación OR RR, OR RR, OR

Tasa de incidencia

sergio.uribe@gmail.com

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