The obesity paradox and mortality after colorectal cancer: A causal conundrum
Menée aux Etats-Unis à partir de données portant sur 3 408 patients atteints d'un cancer colorectal entre 18 et 80 ans, cette étude évalue l'association entre l'indice de masse corporelle, mesuré au moment du diagnostic et 15 mois plus tard, et la mortalité spécifique
Excess body adiposity, commonly approximated as elevated body mass index (BMI; calculated as weight in kilograms divided by height in meters squared), is an established risk factor for increased incidence of several adult cancer types.1 Worldwide, each year, almost a half-million new cancers are attributed to elevated BMI, of which breast, colorectal, and endometrial cancers account for two-thirds.2 By extension, elevated BMI at or after cancer diagnosis might be associated with a poor prognosis in obesity-related cancers, and indeed, a meta-analysis3 of 82 studies have found such associations for breast cancer. This is a key rationale for weight management strategies in cancer survivorship programs and endorsed by clinical guidelines, for example, those from the American Society for Clinical Oncology.4
JAMA Oncology , éditorial, 2015