手術で精神保健治療が年8%減ると主張した研究――2020年の訂正では、手術なしと比べて利益なし

性別肯定手術後のトランスジェンダーの人々における精神保健治療の利用の減少：全人口研究

Authors: Richard Bränström, John E. Pachankis
Journal: American Journal of Psychiatry
Year: 2020
Source: https://doi.org/10.1176/appi.ajp.2019.19010080

Summary

This Swedish study was widely reported in 2019 as showing that gender surgery improves long-term mental health. Using national health records, it found that people diagnosed with gender incongruence used far more mental health care than the general population. Among those who had surgery, people whose last operation was longer ago were less likely to be in treatment in 2015. Hormone treatment showed no such link. Critics pointed out that the data were a one-year snapshot rather than real follow-up, people who had died were left out, and there was no comparison with diagnosed people who had no surgery. When the authors added that comparison, surgery showed no mental health advantage. The journal published a correction in 2020 saying the original conclusion was too strong. As corrected, it gives no evidence that surgery reduces mental health care or suicide attempts.

Key findings

スウェーデンの970万人の住民のうち、2,679人が2005～2015年に性別不合と診断されていました。70%強がホルモンを受け、48%（1,018人）が手術を受けていました。
2015年、診断を受けた人は、うつ病や不安での受診が一般の人々の約6倍、抗うつ薬や抗不安薬の処方が3～4倍、自殺未遂後の入院が6.8倍でした（22人、0.8%対0.1%）。
ホルモンを開始してからの時間は、メンタルヘルス治療に違いをもたらしませんでした。
最後の手術からの経過が1年増えるごとに、2015年のうつ病または不安の治療を受けるオッズは8%低くなっていました。研究はこれを長期的な利益として示しました。
手術から10年以上経っても、メンタルヘルス治療は一般の人々の水準を大きく上回ったままでした。
7通の公表された書簡がデザインを批判した後、著者らは手術を受けた人と受けていない人を比較しました。手術はどの指標でも利点を示さず、2020年8月の訂正は、元の結論を強すぎると述べました。
元の報道と訂正されていない結論は、今も手術がメンタルヘルスを改善するというエビデンスとして広く引用されています。

Abstract

OBJECTIVE: Despite professional recommendations to consider gender-affirming hormone and surgical interventions for transgender individuals experiencing gender incongruence, the long-term effect of such interventions on mental health is largely unknown. The aim of this study was to ascertain the prevalence of mood and anxiety disorder health care visits and antidepressant and anxiolytic prescriptions in 2015 as a function of gender incongruence diagnosis and gender-affirming hormone and surgical treatment in the entire Swedish population. METHODS: This study used the Swedish Total Population Register (N=9,747,324), linked to the National Patient Register and the Prescribed Drug Register. Among individuals who received a diagnosis of gender incongruence (i.e., transsexualism or gender identity disorder) between 2005 and 2015 (N=2,679), mental health treatment in 2015 was examined as a function of length of time since gender-affirming hormone and surgical treatment. Outcome measures were mood and anxiety disorder health care visits, antidepressant and anxiolytic prescriptions, and hospitalization after a suicide attempt. RESULTS: Compared with the general population, individuals with a gender incongruence diagnosis were about six times as likely to have had a mood and anxiety disorder health care visit, more than three times as likely to have received prescriptions for antidepressants and anxiolytics, and more than six times as likely to have been hospitalized after a suicide attempt. Years since initiating hormone treatment was not significantly related to likelihood of mental health treatment (adjusted odds ratio=1.01, 95% CI=0.98, 1.03). However, increased time since last gender-affirming surgery was associated with reduced mental health treatment (adjusted odds ratio=0.92, 95% CI=0.87, 0.98). CONCLUSIONS: In this first total population study of transgender individuals with a gender incongruence diagnosis, the longitudinal association between gender-affirming surgery and reduced likelihood of mental health treatment lends support to the decision to provide gender-affirming surgeries to transgender individuals who seek them.

Conclusion

Original conclusion (2019): in this first total population study of transgender individuals with a gender incongruence diagnosis, the longitudinal association between gender-affirming surgery and reduced likelihood of mental health treatment lends support to the decision to provide gender-affirming surgeries to transgender individuals who seek them. Correction (Am J Psychiatry, August 2020): after letters raised methodological concerns, the journal obtained further statistical review. The authors reanalysed the data comparing individuals diagnosed with gender incongruence who had received surgery with those who had not. This comparison was retrospective and not part of the original question, but the results 'demonstrated no advantage of surgery' for subsequent mood or anxiety disorder-related care visits, prescriptions, or hospitalisations after suicide attempts, and the original conclusion was judged too strong.

Methodological limitations

Conclusion was corrected: The August 2020 correction says comparing diagnosed people who had surgery with those who did not 'demonstrated no advantage of surgery' for depression and anxiety care, prescriptions or hospital stays after suicide attempts. The original conclusion was judged too strong (Correction, Am J Psychiatry 2020; editor's comment by Kalin, 2020).
A snapshot, not follow-up: Mental health treatment was measured only in 2015. 'Years since surgery' compares different people at one time, not the same people before and after surgery, so it cannot show surgery caused any change.
No comparison group at first: The original study did not compare people who had surgery with similar people who didn't. When this was added, the apparent benefit disappeared.
People who died were left out: Only people alive at the end of 2014 were included, and suicide deaths were not counted. People who had surgery and later died, including by suicide, were missing from the 'years since surgery' groups.
Healthier people may get surgery sooner: People with better mental health may be more likely to be approved for surgery and to have had it earlier. There was no data on mental health before surgery, and several of the seven letters raised this.
Few people at long follow-up: The trend relied on small groups whose surgery was many years earlier. Critics noted that a handful of people changing would erase it, and only 22 people in total were hospitalised after a suicide attempt.
Many tests without adjustment: Several outcomes and definitions were tested without allowing for the number of tests, a point raised in SEGM's analysis of the correction.
Using care is not the same as mental health: People longer after surgery may simply have less contact with health services, which the authors acknowledge.
Records only start in 2005: Surgery and hormone records only went back to 2005 (prescriptions to July 2005), so 'years since' stopped at about 10. Earlier treatments, birth sex, legal sex history and gender identity were unknown.
Overstated title and claims: The title ('Reduction…After Gender-Affirming Surgeries') and the claim that the findings 'lend support' to surgery went beyond what a one-year snapshot of links can show. The title was not changed after the correction.

detrans.ai

Summary

Key findings

Abstract

Conclusion