Recent studies have shown that cancer risk related to overweight and obesity is mediated by time and might be better approximated by using life years lived with excess weight. In this study we aimed to assess the impact of overweight duration and intensity in older adults on the risk of developing different forms of cancer. Study participants from seven European and one US cohort study with two or more weight assessments during follow-up were included (n = 329,576). Trajectories of body mass index (BMI) across ages were estimated using a quadratic growth model; overweight duration (BMI ≥ 25) and cumulative weighted overweight years were calculated. In multivariate Cox models and random effects analyses, a longer duration of overweight was significantly associated with the incidence of obesity-related cancer [overall hazard ratio (HR) per 10-year increment: 1.36; 95 % CI 1.12-1.60], but also increased the risk of postmenopausal breast and colorectal cancer. Additionally accounting for the degree of overweight further increased the risk of obesity-related cancer. Risks associated with a longer overweight duration were higher in men than in women and were attenuated by smoking. For postmenopausal breast cancer, increased risks were confined to women who never used hormone therapy. Overall, 8.4 % of all obesity-related cancers could be attributed to overweight at any age. These findings provide further insights into the role of overweight duration in the etiology of cancer and indicate that weight control is relevant at all ages. This knowledge is vital for the development of effective and targeted cancer prevention strategies.

中文翻译：

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老年人超重持续时间与癌症风险：欧洲和美国队列研究。


最近的研究表明，与超重和肥胖相关的癌症风险是由时间介导的，并且可以通过使用体重超重的寿命来更好地估计。在这项研究中，我们旨在评估老年人超重持续时间和强度对患不同形式癌症的风险的影响。来自七项欧洲和一项美国队列研究的研究参与者在随访期间进行了两次或多次体重评估（n = 329,576）。使用二次增长模型估计不同年龄段的体重指数（BMI）轨迹；计算超重持续时间（BMI≥25）和累积加权超重年数。在多变量 Cox 模型和随机效应分析中，较长的超重持续时间与肥胖相关癌症的发病率显着相关[每 10 年增量的总体风险比 (HR)：1.36； 95% CI 1.12-1.60]，但也增加了绝经后乳腺癌和结直肠癌的风险。此外，超重程度进一步增加了肥胖相关癌症的风险。男性与较长超重持续时间相关的风险高于女性，并且吸烟会减弱这种风险。对于绝经后乳腺癌，风险增加仅限于从未使用过激素治疗的女性。总体而言，所有与肥胖相关的癌症中有 8.4% 可归因于任何年龄段的超重。这些发现进一步深入了解了超重持续时间在癌症病因学中的作用，并表明体重控制在所有年龄段都是相关的。这些知识对于制定有效且有针对性的癌症预防策略至关重要。