Introducción: La resistencia a la insulina (RI) es un síndrome metabólico producto de la fisiopatología de la diabetes. Evidencia indirecta indica que existe menor probabilidad de las enfermedades asociadas a RI en lugares de muy alta altitud. El objetivo de esta tesis fue estimar la asociación entre vivir a muy alta altitud (≥ 3500 msnm) y RI en una cohorte peruana. Metodología: Análisis longitudinal de base secundaria de la cohorte CRONICAS en Perú. Se incluyeron adultos de tres sitios del Perú. La RI fue definida como un HOMA-IR ≥ 2.91. La variable de exposición fue el nivel de altitud: muy alta altitud (≥ 3500 msnm) y nivel del mar (0 msnm). También se evaluó nivel de urbanización (Lima, Tumbes, Puno Urbano y Puno rural). Se calcularon las tasas de incidencia de RI para la variable de exposición “nivel de altitud” y urbanización, y se calcularon las razones de tasas de incidencia (RTI). Se evaluó la multicolinealidad con el factor de inflación de la varianza. Resultados: Se analizaron 1730 participantes, cuya media de seguimiento fue 35.4 meses. Las proporciones de participantes fueron similares entre los sitios (Lima: 34.9%, Puno: 32%, Tumbes: 33.1%). La tasa de incidencia de RI en muy alta altitud fue 6.06 (IC95%: 4.77-7.70), mientras que a nivel del mar fue 5.57 (IC95%: 4.87-6.36). La razón de la tasa de incidencia entre vivir a muy alta altitud comparado al nivel del mar fue 0.68 (IC95%: 0.52-0.88), lo que evidencia que existe menor riesgo de RI en el primer grupo. A pesar de este resultado, al analizar la variable de urbanización, vivir en Puno rural asoció a RI significativamente (RTI: 0.58, IC95%: 0.34-1.00), mientras que Puno urbano no se asoció a RI. Asimismo, vivir en Tumbes estuvo asociado a un mayor riesgo de RI (RTI: 1.58, IC95%: 1.19-2.10). Conclusiones: En nuestra cohorte, se encontró una asociación estadísticamente significativa entre vivir en muy alta altitud y un menor riesgo de RI, sin embargo, al analizar los componentes de esta variable (Puno urbano y Puno rural), residir en Puno urbano no se asoció con RI, pero residir en Puno rural (rural a alta altitud) sí se asoció a un menor riesgo de desarrollo de RI por lo que es posible que la ruralidad haya jugado un rol “protector”.Introduction: Insulin resistance (IR) is a metabolic syndrome resulting from the pathophysiology of diabetes. It is associated with increased hospitalizations and mortality. Various clinical factors that predispose to IR have been studied, however, there is little evidence on the relationship between IR and environmental characteristics, such as altitude. Indirect evidence indicates that there is a lower probability of diseases associated with IR in very high-altitude places. The objective of this thesis was to estimate the association between living at very high altitude (≥ 3500 m) and IR in a Peruvian cohort. Methodology: Secondary longitudinal analysis of the 2010 CRONICAS cohort from Peru. Individuals over 35 years of age from three sites of Peru were included. Participants with IR at baseline, diabetes mellitus, and missing glucose and insulin values were excluded. The outcome variable was IR, defined as a HOMA-IR ≥ 2.91. The exposure variable was altitude, categorized as very high altitude (≥ 3500 masl) and sea level (0 masl). Relative risks (RR) and their respective confidence intervals (95% CI) were estimated using generalized linear models of the Poisson family with robust variance. Three models were developed: unadjusted, a model adjusted for socioeconomic variables, and a final model where clinical and laboratory variables were added. Multicollinearity was assessed with the variance inflation factor. Incidence rates for the exposure variables "altitude level" and urbanization were calculated, and incidence rate ratios (IRRs) were calculated. Multicollinearity was assessed using the variance inflation factor. Results: 1730 participants were analyzed, with a mean follow-up of 35.4 months. The proportions of participants were similar between sites (Lima: 34.9%, Puno: 32%, Tumbes: 33.1%). The cumulative incidence of RI was approximately 17%. In the model adjusted for sociodemographic variables, living at high altitude was found to be associated with a decreased risk of IR (RR: 0.66, 95% CI: 0.49-0.87) compared to living at sea level. The incidence rate ratio for living at very high altitudes compared to sea level was 0.68 (95% CI: 0.52-0.88), demonstrating a lower risk of IR in the former group. Despite this result, when analyzing the site variable, which was used to develop the altitude variable, it was evident that living in urban Puno (one of the two places that make up the high altitude category) was not associated with a lower risk of IR; however, living in rural Puno (the other site that makes up the high altitude category) was significantly associated with IR (IRR: 0.58, 95% CI: 0.34-1.00). Likewise, living in Tumbes was associated with a higher risk of IR (IRR: 1.58, 95% CI: 1.19-2.10). Conclusions: In our cohort, living at very high altitudes was associated at a statistically significant level with a lower risk of IR; however, when analyzing the components of this variable (urban Puno and rural Puno), residing in urban Puno was not associated with IR, but residing in rural Puno (a rural place at high altitude) was associated with a lower risk of developing IR, so it is possible that rurality played a “protective” role.