Prospective study of growth and development in older girls and risk of benign breast disease in young women.

backgroundIn adult women with retrospective data, childhood adiposity, pubertal growth and development were associated with benign breast disease (BBD) and/or breast cancer. The authors prospectively evaluated these childhood/adolescent characteristics and BBD risk.

methodsThe Growing Up Today Study (GUTS) included females, aged 9-15 years in 1996, who completed annual questionnaires through 2001, then 2003, 2005, and 2007. Participants annually/biennially provided information on menarche, height, and weight, from which the authors derived body mass index (BMI in kg/m(2) ). Peak height growth velocity (PHV in cm/year) was estimated from longitudinal data. On 2005-2007 surveys, 6899 females (18-27 years of age) reported whether a healthcare provider ever diagnosed BBD (n = 147), and whether it was confirmed by biopsy (n = 67). Logistic models investigated risk factors adjusted for age, alcohol, pregnancy, and maternal history.

resultsMore childhood adiposity (odds ratio [OR], 0.91/[kg/m(2) ]; P = .04) and shorter adult height (OR, 0.93/inch shorter; P = .07) were associated with lower risk of biopsy-confirmed BBD. Girls with most rapid height growth were at increased risk (OR, 2.12; P = .09) relative to those with the slowest growth. Age at menarche was not associated (OR, 1.11/year; P = .32) nor was adult BMI (adjusted for childhood BMI: OR, 1.01/[kg/m(2) ]; P = .98); larger BMI increases (childhood to adulthood) were not protective (OR + 1.04/[kg/m(2) ]; P = .37). Among girls with maternal breast cancer, those with more rapid growth had higher risk (OR, 1.47/[cm/year]; P = .02). All estimates were age-adjusted.

conclusionsIncreased BBD risk (likely evolving to elevated breast cancer risk) was observed in thinner girls, girls with the most rapid growth, and taller women. Contrary to expectations, later menarche age was not protective against BBD, consistent with studies that found BBD patients are not protected against breast cancer by later menarche.