In population-based longitudinal studies, bias caused by nonresponse among eligible participants and attrition during follow-up thwarts conclusions. As this issue is not commonly addressed in dental studies, it is the aim of this study to examine the consequences of attrition with respect to tooth loss and mortality in a 10-y follow-up study. From the Study of Health in Pomerania (SHIP-0), a biological age (BA) score was constructed from 10 systemic biomarkers and related to one’s actual chronological age (CA). The 3,417 dentate participants were stratified according to their BA-CA scores into tertiles: individuals with younger BA than their CA, those with concurrent BA and CA, and those with older BA than their CA. Baseline characteristics and propensity of leaving or remaining in the study were compared across these tertiles. We compared the characteristics within BA strata in the remainers of SHIP-2 (10-y follow-up) and their impact on tooth loss. Besides dropout by those who died, the attrition propensity of baseline study participants was dose dependent as related to BA-CA scores and socioeconomic factors. BA younger participants were underrepresented in dropouts but overrepresented in remaining follow-up participants. BA younger participants had a more favorable risk profile, better oral health, and a lower mortality rate than BA older participants. For the BA older participants, the opposite was observed. Remainers attaining the follow-up SHIP-2 were healthier and more health conscious. After 10 y, their tooth retention was still directed by BA constructed at baseline. The results support the assumption that individual risk profiles aggregated in BA constitute characteristic susceptibility patterns affecting perseverance or attrition in long-term follow-up studies. Attrition, which is common to follow-up studies, changes the study composition of participants depending on their BA and hence the transferability of results to the baseline population. The baseline BA gradient persists even after a long time.

中文翻译：

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后续研究中影响磨损和牙齿脱落的生物年龄


在基于人群的纵向研究中，由合格参与者的无反应和随访期间的流失引起的偏倚阻碍了结论。由于这个问题在牙科研究中通常不涉及，因此本研究的目的是在 10 年随访研究中检查损耗对牙齿脱落和死亡率的影响。根据波美拉尼亚健康研究 （SHIP-0），生物年龄 （BA） 评分由 10 个系统生物标志物构建，并与一个人的实际实际年龄 （CA） 相关。3,417 名齿状参与者根据他们的 BA-CA 分数分为三分位数：BA 比 CA 年轻的个体，同时患有 BA 和 CA 的个体，以及 BA 比 CA 老的个体。我们比较了 SHIP-2 剩余部分 （10 年随访） BA 层内的特征及其对牙齿脱落的影响。除了死亡者的退出外，基线研究参与者的流失倾向与 BA-CA 评分和社会经济因素相关，是剂量依赖性的。BA 年轻参与者在退出者中的代表性不足，但在剩余的随访参与者中代表性过高。与 BA 老年参与者相比，BA 年轻参与者具有更有利的风险状况、更好的口腔健康和更低的死亡率。对于 BA 年龄较大的参与者，观察到相反的情况。获得随访 SHIP-2 的留欧者更健康，更注重健康。10 年后，他们的牙齿保持仍然由基线构建的 BA 指导。 结果支持以下假设，即 BA 中汇总的个体风险概况构成了影响长期随访研究中毅力或损耗的特征性易感性模式。流失在随访研究中很常见，它根据参与者的 BA 改变了他们的研究构成，从而改变了结果向基线人群的可转移性。即使经过长时间，基线 BA 梯度仍然存在。