遺伝性非ポリポーシス大腸がんに関連する遺伝子検査の結果開示後の精神的苦痛と罪責感

Psychological Distress and Feelings of Guilt after Disclosure of Genetic Test Results Regarding Hereditary Nonpolyposis Colorectal Cancer

要旨

　目的：遺伝性非ポリポーシス大腸がん（HNPCC）に関連する遺伝子検査の結果開示1ヵ月後，12ヵ月後における，発端者と未発症家系員の精神的苦痛および罪責感について明らかにすることを目的とした．

　方法：A病院の遺伝相談外来で遺伝子検査を受けたHNPCCに関連するがんを発症している発端者，家系内でHNPCCに関連する遺伝子変異が同定されている未発症家系員を対象に，精神医学的構造化診断面接法を用いて遺伝子検査の結果開示後の精神的苦痛を評価した．また，半構造化面接法により結果開示後の罪責感を調査した．

　結果：HNPCCの遺伝子検査を受けた52名中47名にベースライン調査を実施し，1ヵ月後は42名（89％），12ヵ月後は30名（64％）が完遂した．この30名を対象に解析を行った．結果開示1ヵ月後，12ヵ月後に，重篤な精神的衝撃はみられなかった．しかし，精神的な脆弱性をもつ対象者において12ヵ月後に精神的苦痛を生じやすい可能性が示唆された．また，結果開示後の罪責感は，遺伝子検査の結果にかかわらず，発端者と未発症家系員の両者にみられた．

　結論：対象者の精神的な脆弱性の有無を早期にアセスメントし，家系全体を対象とした長期的な視点で支援する体制を整えていくことが必要である．

Abstract

　Purpose：To reveal psychological distress and feelings of guilt of probands and unaffectedrelatives at 1 and 12 months after the disclosure of genetic test results regarding hereditarynonpolyposis colorectal cancer （HNPCC）.

　Methods：Participants of the research were probands who fulfilled HNPCC criteria andtheir unaffected relatives. The participants consisted of those who visited the outpatient clinicfor cancer genetics, and those who were underwent a genetic test for HNPCC. The structuredclinical interview was used in order to investigate psychological distress of probandsand unaffected relatives at 1 and 12 months after the disclosure of genetic test results regardingHNPCC. The feelings of guilt were also investigated using semistructured interviews.This is a descriptive prospective cohort study.

　Results：The object of analysis was 30 who completed the final interview conducted 12months after the disclosure of genetic test results for HNPCC. The disclosure of genetic testresults related to HNPCC did not have a significant psychological impact, as none of theprobands or relatives met the criteria at the time of the 1-month or 12-months follow-up interview.It was revealed that predictive factor for long-term psychological distress was theparticipants' innate psychological weakness. Feelings of guilt were observed regardless ofgenetic test results.

　Conclusion：This suggests that nurses who are in charge of genetic counseling should assesswhether or not psychological weakness is observed within probands or their relativesas soon as possible, and set up a system to provide long-term support.