Transgender Identity and Suicide Attempts and Mortality in Denmark

Elevated rates of suicide despite wide accessibility of gender transition interventions

A recently published study from Denmark compared the rate of suicide attempts, suicide-related deaths, non-suicide-related deaths, and all-cause mortality between non-transgender and transgender-identifying individuals. The study spanned 42 years, however the average follow-up for transgender-identified individuals was less than six years. The study found that transgender-identifying individuals in Denmark had significantly elevated rates of all four adverse outcomes.

The absolute risk of death by suicide among transgender-identified individuals was estimated as 75 suicides per 100,000 patient-years (standardized adjusted rate). A clinician would need to treat 1,333 transgender-identified patients for a year to encounter one patient death by suicide (100,000/75). Compared to the general population, transgender-identified individuals were 7-8 times more likely to attempt suicide, 3.5 times more likely to die by suicide, and twice as likely to die from non-suicide related causes.

The study considered an individual to be transgender after they changed their legal sex marker or obtained a gender-related diagnosis. It is unclear whether individuals with adverse outcomes have been treated with “gender-affirming” hormonal and/or surgical interventions. However, the authors note that “in 2017, new guidelines were implemented to make transgender health care more accessible.” Thus, it is likely safe to assume that most of those who desired “gender-affirming” interventions had the opportunity to access them.

Several other key findings were apparent in the data but were not elaborated by the authors. The data reveal that Denmark experienced an influx of gender-dysphoric adolescents beginning in 2015-2017 that was disproportionately female. The data also show that trans-identified individuals in Denmark have a markedly elevated rate of psychiatric illness compared to non-trans-identified individuals (43% vs 7%).

The study authors focused on minority stress as the explanation for the increased rate of adverse outcomes in trans-identifying populations (e.g., the deleterious effects of bullying, discrimination, exclusion, and prejudice). Consistent with this interpretation, they recommended suicide-prevention measures such as fighting structural discrimination, and encouraging trans-identified people in distress to seek help. The authors did not mention that there is a strong link between psychiatric illness and suicidality, nor did they comment on the need to provide evidence-based psychiatric care to better address psychiatric conditions that were highly prevalent among the transgender-identified individuals in the study.

The study has several strengths and limitations. Its strengths include obtaining follow-up data on all individuals (as opposed to losing a significant proportion of participants to follow-up); use of objective outcome measures (rather than subjective self-reported measures); focus on serious suicidal behaviors (as opposed to combining serious suicide attempts with non-suicidal self-harm, as is often the case in recent studies); and reporting the absolute risk of suicide among trans-identified individuals (rather than only reporting relative risk, which can be used to exaggerate risk).

The study’s limitations are lack of information about the hormonal or surgical interventions for the transgender cohort; limiting the study to persons age 15 years or older, which eliminates a significant proportion of the population that seeks and receives “gender-affirming” care; lack of representation of transgender-identified individuals who do not seek medical services and do not pursue legal sex marker change; and exclusion of transgender-identified individuals who attempted suicide before their transgender identification was documented, which may have resulted in underestimation of suicide attempts and completed suicides.

Another limitation is a lack of clarity of how the statistical adjustments by decade, age, and sex were conducted, and whether they were sufficient to control for marked epidemiological shift in the presentation of gender dysphoria starting in the mid-2010s. While previously most cases undergoing gender transition were natal males, since about 2015, the sex ratio has shifted strongly toward females, and there has been a sharp rise in the incidence of gender dysphoria in adolescents and young adults, many of whom struggle with pre-existing mental illness and neurocognitive difficulties, such as autism and ADHD. Further, the authors did not control for mental illness when assessing suicidal attempts and deaths. In view of the marked changes in the epidemiology of gender dysphoria since 2015, a separate focus on this novel patient cohort would have allowed for findings that are more applicable to current clinical dilemmas.

Studies in the field of gender medicine often produce conflicting findings (in part due to a lack of rigor in the study designs), yet one finding remains remarkably consistent: transgender-identified individuals continue to suffer from elevated rates of morbidity and mortality, including deaths by suicide. Other studies have reported persistently elevated rates of suicide regardless of the stage of an individual’s transition (from pre-transition assessment to the post-surgical period). Research into suicidality in gender-diverse youth suggests that while their suicidality is elevated, it is comparable to youth who suffer from psychiatric symptoms but do not have gender dysphoria, and that the absolute risk of death by suicide remains low. These facts underscore the need to treat suicidality as a complex multifactorial phenomenon, and strongly point to the conclusion that gender transition should not be viewed as suicide-prevention measure.

The Danish treatment guidelines, which broadened access to gender transition for youth in 2017, will be revised this year (2023), according to the Danish health authority’s website. Over the last 24-26 months, following systematic evidence reviews which found the evidence of benefits of youth gender transition to be highly uncertain, England, Sweden, and Finland have sharply restricted eligibility for youth gender transitions, confined hormonal interventions to research settings, and asserted that psychotherapeutic approaches should be the first line of treatment for gender-dysphoric youth.

It remains to be seen whether the Danish health authority will take a cautious approach to the treatment of gender-dysphoric youth like the growing number of their European counterparts, or whether Denmark will choose to align with the current direction supported by a number of U.S. medical societies that assert that medical gender transition should be widely available for all youths who desire it.

Study findings in detail

There were a total of 12 suicide deaths among 3,759 transgender-identifying individuals (0.3%) over 42 years. This translates into 75 suicides per 100,000 (standardized adjusted rate). All the completed suicides were among natal males; there were no suicide deaths among female trans-identified individuals.

A comparison between transgender- and non-transgender populations revealed that transgender-identified individuals had significantly worse outcomes. Specifically, the rate of suicide attempts among transgender-identified individuals was 7.7 times higher (6.6 times higher in the last decade), suicide mortality was 3.5 times higher (2.8 times higher in the last decade), suicide-unrelated mortality was 1.9 times higher (1.7 times higher over the last decade), and all-cause mortality was two times higher (1.7 times higher over the last decade).

The finding that Danish transgender-identified individuals have elevated rates of psychiatric illness and elevated death rates, including deaths by suicide, is consistent with findings from population studies in other countries. Similarly troubling long-term health outcomes have been found among transgender-identified Dutch, Swedish, and English individuals.

Some of the more notable findings are discussed below.

Findings related to suicide attempts, suicides, and deaths:

There was an elevated rate of suicide attempts and deaths from suicide among transgender-identified individuals. Suicide attempts were seven to eight times higher and suicide deaths were 3.5 times higher in the transgender-identifying population compared to the general population.
There was a higher overall rate of suicide-unrelated mortality of transgender-identified individuals. There were twice as many deaths unrelated to suicide among transgender-identifying individuals, as compared to the non-transgender individuals. The causes of these deaths must be explored. In particular, it is important to determine whether the use of hormones and/or surgical complications may have contributed to the elevated mortality.
There was a relatively low absolute risk of death by suicide among transgender-identified individuals. There was a total of 12 suicides over 42 years, which translates into 75 suicides per 100,000 (standardized adjusted rate). While all suicides are tragic, this number should be viewed in perspective. The average clinician caring for trans-identified individuals would need to treat 1,333 transgender-identified patients to encounter one patient death by suicide (100,000/75).
There were no completed suicides among biologically female transgender-identified individuals. All 12 of the recorded suicides over the 42-year-span were among natal males. While the study authors did not emphasize this finding, it appears to be statistically robust.

Findings related to epidemiology:

The study estimated the prevalence of transgender-identifying individuals in Denmark at 0.06%. The authors report that 3,759 out of a population of 6,657,456 had a gender-related diagnosis or obtained a legal sex change recognition, which represents 0.06% of the total. However, this calculation is at a high risk of bias and is likely an underestimate. This is because the study methodology considered individuals transgender only if they had a gender identity-related diagnosis or a legal sex marker change.

There has been a marked, recent increase in the rate of transgender identification, driven primarily by young people. Although the study covers 42 years, nearly 70% of all transgender-identified individuals in the study are from the last decade, 2010-2021 (See Table 1). This is remarkable. According to Figure 2 (reproduced below), the data are even more skewed, suggesting a sharp increase in the incidence of transgender identification in individuals under 25-30 years old since about 2016-2017, as the dark-blue shading in Figure 2 indicates.

A screenshot of a graph Description automatically generated with low confidence

The data in Table 1 of the study corroborate the disproportionately high prevalence of young people in the trans-identified cohort: 15-24-year-olds account for 25% of the transgender cohort over the last 42 years compared to only 16% of the non-transgender cohort. These numbers are likely even more skewed toward youth in the cases identified since 2015-2017 due to the influx of young individuals since about 2015-2017 (See Figure 2).

There was an increase in the proportion of natal females among the more recently presenting cases. While the authors do not directly observe this fact, the data reveal that most of the older referrals were likely males, while most recent referrals are likely females. This is seen in the calculation of the percent of the sample that is biologically male or female.

When the authors calculate the percentage based on the total transgender-identified individuals in the sample (n=3,759), they say that 1,975, or 52.5%, were birth-recorded males. However, when they report based on person-years—a calculation that gives more weight to the individuals who have been trans-identified the longest—the percentage of males is reported as 58%. This discrepancy can only be explained by the fact that biological males have been in the sample for much longer than biological females. In other words, there has likely been a recent disproportionate influx of females. (This finding, if true, would be consistent with the trend of sharply elevated numbers of adolescent and young adult gender-dysphoric females elsewhere in the Western world.)

Combined with the finding of a sharp increase in the incidence of trans-identification in youth (discussed earlier), the data make it likely that Denmark is experiencing the same trend as other Western countries: a sharp and as yet unexplained increase in the incidence of adolescent and young adult females declaring a transgender identity.

There was a high rate of psychiatric illness among transgender-identified individuals. Nearly half (43%) of trans-identified individuals had at least one psychiatric illness in addition to gender dysphoria, compared with 7% of the general population. This finding deserves careful consideration as psychiatric illness is a key contributor to suicide (individuals with mental illness are far more likely to die by suicide).

Of note, a recent study of transgender-identifying youth across several gender clinics in the U.S. and Europe reported that while their level of suicidality is elevated compared to the general population of peers, it is no different from suicidality rates in non-transgender peers who suffer from psychiatric illness. Further, a long-term study from the Netherlands found that “suicide deaths occurred during every stage of transitioning” at equal rates (Wiepjes et al., 2020, p. 486).

Another (corrected) long-term study from Sweden also found that gender-dysphoric individuals who received hormones and/or surgery did not have lower rates of serious suicide attempts compared to gender-dysphoric individuals who received no medical transition services. In fact, the data for the post-surgical gender-dysphoric individuals suggest a doubling of serious suicide attempts when compared to the gender-dysphoric individuals who did not obtain surgery. The result did not reach statistical significance due to the small number of subjects but is clinically relevant.

These observations suggest that not only is the suicide narrative frequently used to justify medically transitioning minors greatly exaggerated, but that medical gender transition is not an effective suicide-prevention measure. The results also suggest that treatment should focus on better control of co-occurring psychiatric illness and on evidence-based suicide-prevention measures in particular for individuals deemed at high risk for suicide.

Strengths and limitations of the study

In a field that has developed a penchant for deriving its knowledge base from non-comparative studies that rely on online surveys promoted by activist organizations and induced by cash prizes for participation, or from “affirmative” youth gender clinics that often sacrifice the quality of their research to further what they perceive to be social-justice causes, the latest JAMA study is a reminder that objective research is still possible.

The study has a number of strengths, elaborated below:

Study strengths:

Use of objective outcome measures. Rather than relying on subjective self-reported measures (e.g., recall of suicidal ideation or attempts, or self-reported illness), this study used objective system-recorded mental and physical health outcomes.
Focus on completed suicides and serious suicide attempts, rather than less specific “suicidality.” “Suicidality” is a broad concept that often encompasses a wide range of behaviors from non-suicidal self-harm (e.g., cutting) to serious suicide attempts which typically result in hospitalization. Much of the current research in the field reports on “suicidality” without specifying the severity of the attempts. Because the JAMA study relied on hospital records, it is likely that only more serious suicide attempts were included.
Medium-term outcome data. In contrast to studies that report on 3-24 month follow-up, which are omnipresent in the field, the average follow-up on the transgender-identifying cohort was 5.7 years (21,404 “person-years”/3,759 persons). It should be noted, however, that the effective follow-up may have been shorter. Because of the markedly skewed data, with a disproportionate influx of trans-identified individuals in the last few years, the mean is unduly inflated by the few outlier cases of trans-identified individuals who may have been tracked for much of the 42 years. In such cases, median follow-up is a more informative measure.

While the authors do not provide enough data to determine the median follow-up, in instances where the data are so heavily skewed toward a few cases with long follow-ups, and many cases with short follow-up, the median is always lower than the mean.

The use of absolute risk scores. The ability to report the absolute risk (per 100,000 person-years) for each outcome for both non-transgender and transgender-identifying populations is a key strength of the study. Specific to suicide, this type of calculation enables recognition of the fact that Danish trans-identifying individuals are at 3.5 times the risk of suicide compared to the general population, while also noting that their absolute risk of suicide remains relatively low (as discussed above, a clinician caring for trans-identified individuals would need to treat 1,333 patients to encounter 1 death by suicide (100,000/75).
Standardized, adjusted calculations. Rather than merely aggregating all the data across 42 years, which could have unduly skewed the results, the authors provided a more refined calculation that was standardized and adjusted by decade, age, and sex distribution.
No participant loss to follow-up. Because of the study’s reliance on national registry data, the outcomes for all individuals are known. In contrast, most studies in this field rely on study subjects opting to participate in follow-up research. Such studies routinely lose 20%-60% of participants, raising concerns of bias toward underreporting of adverse outcomes.

Study limitations:

The authors identified some of the study limitations, including the fact that the study was limited to Danish-born individuals (excluding immigrants), as well as individuals who either had a medical diagnosis of gender dysphoria or a legal change of their sex markers. The authors also noted other study limitations, including the fact that serious suicide attempts, as well as transgender identity of the presenting individuals, may be underreported by the Danish hospitals, which may have led to an underestimation of risk.

The study’s limitations, including those not discussed by the authors, are elaborated below:

Lack of information about the treatment status with hormonal or surgical interventions. Based on the data presented, it is impossible to determine whether the elevated rate of suicide attempts occurred before vs after medical transition. However, it is likely that most of those who wished to undergo medical transition had the opportunity to do so: the authors do note that “in 2017, new guidelines were implemented to make transgender health care more accessible.”
Limiting the cohort to persons at least 15 years of age. The decision to limit study subjects to those who were at least 15 years old likely underestimates the total incidence of trans-identified individuals. Data from other countries show that transgender identification in youth has spiked for those aged 12 and older. Youths as young as eight or nine are also the key target of the “gender-affirming” medical treatment model, which recommends starting puberty blockers at the earliest stage of puberty, before proceeding to cross-sex hormones and, eventually, surgery. Thus, a significant proportion of those on the transgender medical treatment pathway are not represented by the study.
Lack of representation of transgender-identified individuals who do not seek medical services and do not pursue legal sex marker change. The study’s strength—the use of objectively verifiable data—is also one of its limitations. The study does not capture trans-identified individuals who do not seek legal sex marker changes and who either do not medicalize, self-medicate outside the healthcare system, or those whose medical providers avoid using identity-related diagnoses due to fear of stigmatization.

The prevalence of trans identification reported by the study (0.06%) is almost certainly an underrepresentation of the true incidence, as the authors report on a nationally representative 2017 Danish study which shows a higher (0.1%) percent rate of trans-identification among 15-89-year-olds. Given the sharp rise in trans-identification in youth in Denmark since 2017 (see Figure 2), the current prevalence of trans identification is likely much higher.

The current analysis of the prevalence and outcomes can be enhanced by an additional analysis of the individuals who lack an identity-related diagnosis but whose health data display a treatment pattern suggestive of “gender-affirming” care (e.g., a mastectomy for a biological female in the absence of a cancer diagnosis, or prescription of puberty blockers for an adolescent with no other medical indications). The estimate of prevalence (but not outcomes) may be strengthened by probability sampling of the Danish population to estimate the rate of transgender self-identification.

Exclusion of trans-identified individuals who attempted suicide before their trans identification became apparent, which may have led to underestimation of suicide attempts and completed suicides. The total number of transgender-identified individuals (n=3,759) was reduced to 3,649 in the suicide attempts and completed suicides analysis. This represents a loss of 3% or 110 study subjects. While this appears to be a relatively small percent, according to the note in Table 2, these 110 subjects were “censored” (removed) from the data because they had attempted suicide prior to the date when they were identified as transgender (i.e., the date of the first gender dysphoria diagnosis or the date of their legal sex marker change). This action eliminated from the dataset individuals who are likely the most prone to suicide attempts, since a key predictor of future suicide attempts is a prior suicide attempt.

We will not speculate about why the authors reasoned that such an exclusion was justifiable, but we do note that had they included such individuals in the dataset, and had they attributed their suicide attempts to the “transgender” cohort, this would have further increased the rate of suicide attempts and possibly suicide deaths in the trans-identified population, and it would have further exacerbated the differential in suicidality between non-transgender and transgender-identified individuals.

Designating individuals as transgender only after the first gender-related diagnosis or legal sex change marker. When analyzing the “transgender” cohort, the authors made the decision to treat these individuals as “non-transgender” until the first time they received a gender identity-related diagnosis or until they had a legal sex marker changed (whichever occurred first). While this methodology makes sense for the estimation of incidence of trans identification, in our opinion it makes less sense for estimating the incidence of conditions and outcomes. Also, it could be argued that an individual does not “become” transgender on the day of the first diagnosis or the day their legal sex marker is changed.
Lack of clarify about the statistical adjustments. The authors note that they standardized the data for calendar period (1980-1989, 1990-1999, 2000-2009, and 2010-2021), sex assigned at birth (male or female), and age (15-24, 25-39, 40-59, 60-79, and 80+ years), and that "indirect standardization was used with the total population as reference." However, without addition detail, it is hard to judge whether this adjustment is sufficient for the last decade (2010-2021), given the marked shift in the population of transgender-identifying individuals seeking care after 2015-2017 (See Figure 2), which may have skewed the last decade’s findings.

For example, it is unclear whether the sharply declined incidence of death by suicide among trans-identified individuals reported in Table 3 (from 161 per 100,000 prior to year 2000, to 40 per 1000,000 between 2001- 2023) represents improved outcomes, or if this improvement is unduly influenced by the recent influx of young natal females who are less likely to experience adverse events due to the recency of their transgender identification. Typically, adverse outcomes in trans-identifying individuals take a decade or more to manifest.

Apparent lack of control for mental health comorbidities. As previously discussed, while the data show a strikingly elevated rate of mental illness among transgender-identified individuals (43% had another psychiatric diagnosis unrelated to gender identity compared to only 7% on the non-transgender population), it does not appear that the authors controlled for this when estimating the rates of suicide attempts and completed suicides. This limitation can be corrected by controlling for psychiatric diagnoses when estimating the incidence of various health outcomes.

SEGM Take-Aways

While studies in gender medicine often produce conflicting results, one finding remains remarkably consistent across multiple studies: despite the wide availability of “gender-affirming” care and especially in recent years, individuals who identify as transgender continue to struggle with a significant burden of psychiatric symptoms and remain at significantly elevated risk of morbidity and mortality.

The key question, which has become the subject of heated debates in medicine, is how to best help the rapidly growing numbers of youth presenting with gender dysphoria. Many of such youths’ transgender identity emerged after puberty, following months and years of struggling with psychiatric illness or neurocognitive conditions, such as ADHD or autistic-spectrum disorders.

The question of the risk of suicide, and the efficacy of “gender-affirmative” medical interventions as suicide prevention measures, remains front and center in this debate. The JAMA study, which centered the question of suicide, will likely be referenced by both, the proponents of wide availably of medical gender transition services for minors, and by those who opposed it.

Those promoting wide access to “gender-affirming” hormonal and surgical interventions for youth may point to the results of the study to reinforce the notion that trans-identified individuals are at markedly high risk of death by suicide if they do not transition. Our analysis above shows that this assertion cannot be supported by the current study (or by other studies in the field).

Those opposing the proliferation of “gender-affirming” care may observe that the absolute risk of suicide among trans-identified individuals is relatively low (1 in 1,333 individuals per year) and that despite the wide availability of “gender-affirming” interventions in Denmark, the rate of death by suicide among trans-identified individuals continues to significantly exceed the general population. They may point to the very high rate of psychiatric comorbidity in the trans-identified population, and question whether it is the underlying untreated psychiatric comorbidity that is the key contributor to the elevated suicidality. They also may emphasize that the study raises questions about the elevated non-suicidal mortality in the trans-identifying population and whether “gender-affirming” hormones and surgery contribute to these adverse outcomes.

Unfortunately, because the study tells us little about the outcomes of youth presenting with a previously atypical, post-pubertal onset of gender dysphoria since 2015-2017, and because of the other significant limitations discussed earlier (notably, a lack of exploration of the significant burden of mental health comorbidity in the trans-identifying population), the study findings have very little applicability to current clinical dilemmas.

While the current JAMA study sheds little light on health outcomes of trans-identified youth, other research does. For example, a recent study using data from the largest pediatric gender clinic in the world, the Tavistock in the UK, shows that, while suicides among trans-identified are elevated, thankfully they remain rare events—there were a total of four suicide deaths among 15,032 patients over a 10-year period (0.03%, or an annualized rate of 13 per 100,000). Importantly, there was no observed difference in the suicide rate between those on the waitlist versus those receiving active evaluation and treatment at the gender clinic.

Further, according to the first principle of evidence-based medicine, treatment decisions should be based on systematic reviews of evidence of treatment effects. To date, every systematic evidence review has concluded that the evidence of psychological benefit of “gender-affirming” puberty blockers, cross-sex hormones and surgery for youth is of very low certainty. In contrast, the harms of hormonal interventions, including infertility, sterility, and adverse effects on bone and cardiovascular health are much better established.

For those concerned with the long-term health of the adolescents and young adults who began to present with gender dysphoria in clinical settings in unprecedented numbers since 2015, this signals the need to de-exceptionalize care of this population. This is consistent with the direction undertaken by a growing number of European countries (England, Sweden, and Finland), which have sharply restricted the eligibility for youth gender transitions, and which now state that psychotherapeutic interventions to control psychiatric illness and explore the nature of gender distress should be the first—and in many cases the only—treatment available outside of research settings.

The Danish treatment guidelines, which broadened access to gender transition for youth in 2017, will be revised this year (2023), according to the Danish health authority’s website. It remains to be seen if Denmark will course-correct, taking a more cautious approach to the treatment of gender-dysphoric youth, following in the footsteps of a growing number of its European counterparts—or whether it will continue to pursue the medicalized approach favored by the North American medical societies.