title: Cancer and frailty in older adults: a nested case-control study of the Mexican Health and Aging Study.
abstract: Understanding how the convergence between chronic and complex diseases-such as cancer-and emerging conditions of older adults-such as frailty-takes place would help in halting the path that leads to disability in this age group. The objective of this manuscript is to describe the association between a past medical history of cancer and frailty in Mexican older adults.
  
  
  
  This is a nested in cohort case-control study of the Mexican Health and Aging Study. Frailty was categorized by developing a 55-item frailty index that was also used to define cases in two ways: incident frailty (incident >0.25 frailty index score) and worsening frailty (negative residuals from a regression between 2001 and 2012 frailty index scores). Exposition was defined as self-report of cancer between 2001 and 2012. Older adults with a cancer history were further divided into recently diagnosed (<10 years) and remotely diagnosed (>10 years from the initial diagnosis). Odds ratios were estimated by fitting a logistic regression adjusted for confounding variables.
  
  
  
  Out of a total of 8022 older adults with a mean age of 70.6 years, the prevalence of a past medical history of cancer was 3.6 % (n = 288). Among these participants, 45.1 % had been diagnosed with cancer more than 10 years previously. A higher risk of incident frailty compared to controls [odds ratio (OR) 1.53 (95 % confidence interval (CI) 1.04-2.26, p = 0.03); adjusted model OR 1.74 (95 % CI 1.15-2.61, p = 0.008)] was found in the group with a recent cancer diagnosis. Also, an inverse association between a remote cancer diagnosis and worsening frailty was found [OR = 0.56 (95 % CI 0.39-0.8), p = 0.002; adjusted model OR 0.61 (95 % CI 0.38-0.99, p = 0.046)].
  
  
  
  Cancer is associated with a higher frailty index, with a potential relevant role of the time that has elapsed since the cancer diagnosis.
  
  
  
  Cancer survivors may be more likely to develop frailty or worsening of the health status at an older age. This relationship seems especially evident among individuals with a recent oncological diagnosis. Health professionals in charge of older adult care should be aware of this association in order to improve outcomes of older adults who survived cancer.
authors: Geriatric Epidemiology Research Department, Instituto Nacional de Geriatría, Periférico Sur 2767, colonia San Jerónimo Lídice, delegación Magdalena Contreras, México DF, México, CP 10200, Mexico. ulises.perez@salud.gob.mx.
authors: Mario Ulises
authors: MU
authors: Pérez-Zepeda
authors: Oncology Service, Hospital 20 de Noviembre, Instituto de Salud y Seguridad Social de los Trabajadores del Estado, Mexico City, Mexico.
authors: Eduardo
authors: E
authors: Cárdenas-Cárdenas
authors: Gérontopôle, Centre Hospitalier Universitaire de Toulouse, Toulouse, France.|Université de Toulouse III Paul Sabatier, Toulouse, France.
authors: Matteo
authors: M
authors: Cesari
authors: Geriatric Department, Instituto Nacional de Ciencias Médicas y Nutrición "Salvador Zubirán", Mexico City, Mexico.
authors: Ana Patricia
authors: AP
authors: Navarrete-Reyes
authors: Principal Office at the Instituto Nacional de Geriatría, Mexico City, Mexico.
authors: Luis Miguel
authors: LM
authors: Gutiérrez-Robledo
mesh_terms: D000368:Aged; D000375:Aging; D016022:Case-Control Studies; D015331:Cohort Studies; D005260:Female; D016330:Frail Elderly; D006304:Health Status; D006801:Humans; D008297:Male; D008800:Mexico; D009369:Neoplasms / Q000523:psychology*; D015995:Prevalence; D017741:Survivors
keywords: Chronic disease; Disability; Frailty; Oncogeriatrics