Department of Physiology and Pharmacology, Karolinska Institutet, Stockholm, Sweden.
Centre for Primary Health Care Research, Department of Clinical Sciences, Malmö, Lund University, Malmö, Sweden.
JAMA Otolaryngol Head Neck Surg. 2019 Mar 1;145(3):222-229. doi: 10.1001/jamaoto.2018.3852.
No effective treatments are currently available for severe tinnitus, which affects 1% of the population and lowers the quality of life. The factors that contribute to the transition from mild to severe tinnitus are poorly known. Before performing genetic analyses and determining the mechanisms involved in the development of severe tinnitus, its heritability needs to be determined.
To examine whether clinically significant tinnitus is associated with genetic factors and to evaluate the genetic risk in the transmission of tinnitus using adoptees.
DESIGN, SETTING, AND PARTICIPANTS: Data from adoptees and their biological and adoptive parents from Swedish nationwide registers were collected from January 1, 1964, to December 31, 2015, and used to separate genetic from environmental factors in familial clustering. In all, 11 060 adoptees, 19 015 adoptive parents, and 17 025 biological parents were investigated. The study used a cohort design and a case-control approach to study genetic and nongenetic factors in tinnitus among adoptees.
The primary outcome was odds ratio (OR) of tinnitus in adoptees with at least 1 affected biological parent compared with adoptees without any affected biological parent using logistic regression. The secondary outcome was OR in adoptees with at least 1 affected adoptive parent compared with adoptees without any affected adoptive parent.
A total of 1029 patients (440 [42.8%] male; mean [SD] age, 62 [14] years) with tinnitus were identified. The prevalence of diagnosed tinnitus was 2.2%. The OR for tinnitus was 2.22 for adoptees (95% CI, 1.03-4.81) of biological parents diagnosed with tinnitus, whereas the OR was 1.00 (95% CI, 0.43-2.32) for adoptees from adoptive parents diagnosed with tinnitus. Mean (SE) heritability determined using tetrachoric correlations was 31% (14%).
The findings suggest that genetic factors are associated with the familial clustering of clinically significant tinnitus with no shared-environment association, revealing that the transition from negligible to severe tinnitus may be associated with genetic factors. These findings may provide insight for future genetic analyses that focus on severe tinnitus.
目前尚无有效的治疗方法可用于治疗影响 1%人群的重度耳鸣，它降低了生活质量。导致轻度耳鸣向重度耳鸣转变的因素尚不清楚。在进行遗传分析并确定与重度耳鸣发展相关的机制之前，需要确定其遗传性。
检验临床上显著的耳鸣是否与遗传因素有关，并通过被领养者评估耳鸣遗传传递的遗传风险。
设计、地点和参与者：从 1964 年 1 月 1 日至 2015 年 12 月 31 日，从瑞典全国登记处收集了领养者及其亲生和领养父母的数据，用于从家族聚集现象中分离出遗传和环境因素。共有 11060 名被领养者、19015 名领养父母和 17025 名亲生父母参与了研究。该研究采用队列设计和病例对照方法，研究了被领养者中遗传和非遗传因素对耳鸣的影响。
主要结局是采用 logistic 回归，比较至少有 1 位受影响的亲生父母的被领养者与没有任何受影响的亲生父母的被领养者发生耳鸣的比值比（OR）。次要结局是比较至少有 1 位受影响的领养父母的被领养者与没有任何受影响的领养父母的被领养者发生耳鸣的 OR。
共纳入 1029 名耳鸣患者（440 名[42.8%]为男性；平均[标准差]年龄为 62[14]岁）。确诊耳鸣的患病率为 2.2%。患有耳鸣的亲生父母的被领养者发生耳鸣的 OR 为 2.22（95%CI，1.03-4.81），而患有耳鸣的领养父母的被领养者发生耳鸣的 OR 为 1.00（95%CI，0.43-2.32）。采用 tetrachoric 相关法确定的均值（SE）遗传率为 31%（14%）。
研究结果表明，遗传因素与临床上显著的耳鸣的家族聚集有关，而与共享环境无关，这表明从轻度耳鸣向重度耳鸣的转变可能与遗传因素有关。这些发现可能为未来关注重度耳鸣的遗传分析提供参考。
