Background While age is an important risk factor for both cancer and frailty, it is unclear whether cancer itself increases the risk of frailty. We aimed to assess the association between cancer and frailty in a longitudinal cohort of older Danish twins, taking familial effect into account. Methods Using the Danish Cancer Registry, cancer cases were identified among participants aged 70 and over in the Longitudinal Study of Aging Danish Twins (LSADT). Frailty was evaluated over 10 years of follow-up using the frailty index (FI) and defined as FI > 0.21. Stratified Cox regressions were performed on discordant twin pairs (pairs where one twin had incident cancer and the other was cancer-free), and on all LSADT individual twins (twin pairs and singletons) with no history of cancer. Results Among the 72 discordant pairs (n=144, median age at inclusion=75) included in the study, the median FI at inclusion was 0.08 for both cancer twins and cancer-free co-twins. From the stratified Cox regression, twins with cancer had an increased hazard of developing frailty (HR=3.67, 95%CI=1.02,13.14) compared to their cancer-free co-twins. The analyses on individual twins (n=4,027) provided similar results, showing an increased hazard of frailty in individuals with cancer (HR=2.57, 95%CI= 1.77,3.74) compared to those without cancer. Conclusions We showed a higher risk of becoming frail following a cancer diagnosis in both discordant twin pairs and individual twins. These findings support the importance of monitoring of frailty in older adults with cancer through geriatric assessments and implementation of frailty interventions.

中文翻译：

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癌症与虚弱有关吗？对老年丹麦双胞胎的纵向研究结果


背景 虽然年龄是癌症和虚弱的重要风险因素，但目前尚不清楚癌症本身是否会增加虚弱的风险。我们旨在评估老年丹麦双胞胎纵向队列中癌症与虚弱之间的关联，同时考虑家族效应。方法 使用丹麦癌症登记处，在丹麦老龄化双胞胎纵向研究 （LSADT） 中确定了 70 岁及以上参与者的癌症病例。使用衰弱指数 （FI） 在 10 年的随访中评估衰弱，定义为 FI > 0.21。对不一致的双胞胎对 （一个双胞胎患有新发癌症而另一个没有癌症的对） 和所有没有癌症病史的 LSADT 个体双胞胎 （双胞胎对和单胎） 进行分层 Cox 回归。结果 在研究纳入的 72 对不一致对 （n=144，入组时中位年龄 = 75） 中，癌症双胞胎和无癌双胞胎入组时的中位 FI 均为 0.08。从分层 Cox 回归来看，与无癌双胞胎相比，患有癌症的双胞胎发生虚弱的风险增加 （HR=3.67,95%CI=1.02,13.14）。对个体双胞胎 （n=4,027） 的分析提供了类似的结果，显示与非癌症患者相比，癌症患者 （HR=2.57,95%CI= 1.77,3.74） 虚弱的风险增加。结论 我们显示，不一致的双胞胎对和个体双胞胎在癌症诊断后变得虚弱的风险更高。这些发现支持通过老年病学评估和实施衰弱干预来监测老年癌症患者衰弱的重要性。