MENTAL PROBLEMS
Is
Sexual Orientation Related to Mental Health Problems and Suicidality in Young
People?
David M. Fergusson,
PhD; L. John Horwood, MSc; Annette L. Beautrais, PhD
American
Medical Association
Background This study examines the extent to which gay, lesbian, and bisexual young people are at increased risk of psychiatric disorder and suicidal behaviors using data gathered on a New Zealand birth cohort studied to age 21 years.
Methods Data were gathered during the course of the Christchurch Health and Development Study, a 21-year longitudinal study of a birth cohort of 1265 children born in Christchurch, New Zealand. At 21 years of age, 1007 sample members were questioned about their sexual orientation and relationships with same-sex partners since the age of 16 years. Twenty-eight subjects (2.8%) were classified as being of gay, lesbian, or bisexual sexual orientation. Over the period from age 14 to 21 years, data were gathered on a range of psychiatric disorders that included major depression, generalized anxiety disorder, conduct disorder, and substance use disorders. Data were also gathered on suicidal ideation and suicide attempts.
Results Gay, lesbian, and bisexual young people were at increased risks of major depression (odds ratio [OR], 4.0; 95% confidence interval [CI], 1.8-9.3), generalized anxiety disorder (OR, 2.8; 95% CI, 1.2-6.5), conduct disorder (OR, 3.8; 95% CI, 1.7-8.7), nicotine dependence (OR, 5.0; 95% CI, 2.3-10.9), other substance abuse and/or dependence (OR, 1.9; 95% CI, 0.9-4.2), multiple disorders (OR, 5.9; 95% CI, 2.4-14.8), suicidal ideation (OR, 5.4; 95% CI, 2.4-12.2), and suicide attempts (OR, 6.2; 95% CI, 2.7-14.3).
Conclusions Findings support recent evidence suggesting that gay, lesbian, and bisexual young people are at increased risk of mental health problems, with these associations being particularly evident for measures of suicidal behavior and multiple disorder.
Arch Gen Psychiatry. 1999;56:876-880
IN RECENT years, there has
been growing concern and debate about the extent to which young people of gay,
lesbian, or bisexual (GLB) sexual orientation are at increased risk of mental
health problems.1-5
These issues have emerged in clear relief in the context of debates about
whether GLB young people are at increased risk of suicide and suicidal
behaviors. Specifically, it has been argued that because of a series of social
processes that center on homophobic attitudes, GLB youth are exposed to serious
personal stresses that increase their likelihood of suicidal behavior.6-8
However, a reappraisal of these claims showed them not to be well founded in
evidence, and reviews of this issue concluded that problems in existing research
were such that no clear conclusions about the role of sexual orientation in
suicidal behavior could be drawn.7,
8
Nonetheless, in the last 2
years there have been an increasing number of studies that have compared
representative samples of GLB youth with heterosexual controls, with these
studies all suggesting increased rates of suicide attempts among GLB youth.
Bagley and Tremblay1
in a study of 82 homosexual or bisexual men aged 18 to 27 years and 668
heterosexual men found that rates of suicidal behaviors were nearly 14 times
higher among the gay or bisexual subjects. Garofalo et al2
compared 104 GLB high school students with 4055 high school students identifying
themselves as heterosexual. They found rates of suicide attempt among the GLB
subjects that were more than 3.5 times higher than among the control subjects.
Similarly, Remafedi et al3
compared 394 GLB high school students with 336 heterosexual controls. Their
findings showed that the GLB subjects had odds of suicide attempt that were 7.1
times higher than heterosexual controls and odds of suicidal intent that were
3.6 times higher. The weight of evidence from these studies clearly supports the
view that GLB sexual orientation acts as a risk factor for suicidal behaviors.
In contrast to the growing
body of literature on sexual orientation and suicide, there is less systematic
evidence on the extent to which GLB youth are at greater risk of mental health
problems, although there is a widespread belief that GLB youth are at greater
risk of these problems.2,
9 In
addition, Hartstein5
has emphasized the importance of gathering data on the mental health of
contemporary cohorts of young people since, because of changing political,
social, and health factors, cohort specificity will limit the applicability of
research done in previous decades.
In this article we report
the results of a 21-year longitudinal study of a birth cohort of more than 1000
New Zealand young people. The aims of this study were (1) to estimate the
proportion of young people in the cohort who by age 21 years reported being of
GLB sexual orientation, and (2) to examine the relationships between GLB sexual
orientation and estimates of lifetime prevalence of suicidal behaviors (suicidal
ideation and suicide attempt) and common psychiatric disorders (major
depression, generalized anxiety disorder, substance use disorders, and conduct
disorder). The study is characterized by a number of features that include the
use of a relatively large and representative population sample, the measurement
of psychiatric disorder throughout adolescence and young adulthood using
standardized (DSM-III-R10
and DSM-IV11)
diagnostic criteria, and the collection of prospective social, family, and
childhood information.
SUBJECTS AND METHODS
SUBJECTS
The data described in this report were gathered during the course of the
Christchurch Health and Development Study, a longitudinal study of a birth
cohort of New Zealand–born children who have been studied from birth to age 21
years. The cohort was based on an unselected sample of births (635 men; 630
women) occurring in the Christchurch urban region during mid-1977. The cohort
has now been studied at birth, 4 months of age, 1 year of age, annual intervals
to the age of 16 years, and again at ages 18 and 21 years. The present analysis
is based on a sample of 1007 subjects for whom data on sexual orientation were
available. This sample represented 80% of the original cohort of 1265 subjects.
Comparison of the sample of 1007 subjects with the original cohort of 1265
subjects showed that the obtained sample did not differ from the original cohort
in terms of sex, ethnic status, or family size. However, there were small but
statistically significant tendencies for the obtained sample to underrepresent
children of young mothers (P = .046), children born into single parent
families (P<.001), and children from families of low socioeconomic
status (P<.001). It is unlikely that these small departures from
random sample loss assumptions will materially influence the validity of the
present analysis since the factors related to sample loss were uncorrelated with
sexual orientation (see the "Social, Family, and Childhood Factors"
subsection of the "Subjects and Methods" section).
SEXUAL ORIENTATION
When cohort members were aged 21 years, they were questioned in detail about
their sexual orientation. This questioning involved asking the subjects to
nominate their sexual orientation on a 3-fold classification in terms of
heterosexual, homosexual (gay or lesbian), or bisexual. Following this, subjects
were questioned about their sexual relationships with same-sex and different-sex
partners. This questioning covered the numbers of same-sex and different-sex
partners with whom the respondent had a sexual relationship since the age of 16
years. All questioning was conducted by trained survey interviewers recruited
for the project, and the interview was administered personally and in private.
Of the 1007 subjects questioned at age 21 years, 20 (2%) identified themselves
as GLB. In addition, a further 8 subjects self-identified as heterosexual but
disclosed that they had had sexual relationships with a same-sex partner since
the age of 16 years. Using this information, a classification of GLB orientation
was constructed by including into the definition all of those who reported GLB
sexual orientation or those reporting having same-sex partnerships. Of the 28
subjects (11 men; 17 women) classified as GLB, 24 (86%) reported having sexual
relationships with a same-sex partner since the age of 16 years. Of the 20
subjects reporting that their sexual orientation was GLB, 9 were male and 11
were female.
PSYCHIATRIC DISORDER
To examine the association between sexual orientation and psychopathology, a
series of measures of the prevalence of psychiatric disorder observed over the
period from age 14 to 21 years was constructed. The decision to assess long-term
psychopathologic characteristics rather than current mental state was made on
the grounds that stresses related to GLB sexual orientation were likely to have
occurred throughout adolescence and into young adulthood and, accordingly, the
effects of these stresses on adjustment would be more accurately reflected in
the long-term prevalence of disorder rather than in measures of current
disorder. Accounts of the measurement of psychiatric disorder in the cohort over
the period from age 14 to 21 years have been given in a number of Christchurch
Health and Development Study publications.12-17
In the interests of brevity, a short summary of these accounts is given below.
When cohort members were
aged 15 and 16 years, subjects and their parents were interviewed using
structured interview schedules that examined various aspects of the young
person's mental health over the preceding year. These interviews combined
elements of the Diagnostic Interview for Children,18
the Diagnostic Interview Schedule,19
the Self-Report Early Delinquency Scale,20
and the Rutgers Alcohol Problems Index21
together with some custom-written survey items to assess DSM-III-R
symptom criteria for common psychiatric disorders. Using this information, the
parent and self-report symptom data were combined to classify subjects on the
following DSM-III-R diagnoses: major depression, generalized anxiety
disorder, conduct disorder, nicotine dependence, and alcohol and other illicit
substance abuse and/or dependence.
At ages 18 and 21 years,
subjects were again interviewed on a structured schedule that examined the young
person's mental health over the period from ages 16 to 18 years and 18 to 21
years, respectively. This interview used the Composite International Diagnostic
Interview22
and the Self-Report Delinquency Inventory23
to assess DSM-IV symptom criteria for the following diagnoses: major
depression; generalized anxiety disorder; conduct disorder; nicotine dependence;
and alcohol and other illicit substance abuse and/or dependence. For the
purposes of the present analysis, the diagnostic information from these
assessments was combined to construct measures of whether the subject had ever
met criteria for major depression, generalized anxiety disorder, conduct
disorder, nicotine dependence, other substance abuse and/or dependence, and
multiple (>2) disorders during the period from age 14 to 21 years.
SUICIDAL BEHAVIORS
At ages 15, 16, 18, and 21 years, subjects were asked whether they had ever
experienced suicidal thoughts or made a suicide attempt since the last
interview. In addition, at age 15 years, subjects were questioned about whether
they had ever had suicidal thoughts or made a suicide attempt. An account of the
measurement of suicidal behavior has been given in previous studies.15,
24, 25
By age 21 years, 29.1% of the cohort had reported suicidal ideation, and 7.8%
had reported making at least one suicide attempt.
SOCIAL, FAMILY, AND
CHILDHOOD FACTORS
One explanation of elevated rates of disorder or suicidal behavior among GLB
youth is that these could reflect social, family, and childhood factors that
were associated with GLB status and were also related to later mental health. To
examine the equivalence of the GLB and control groups, a large number of
comparisons were made on the childhood, family, and social backgrounds of both
groups prior to the age of 14 years. These comparisons involved measures of
sociodemographic background (maternal age, education, ethnicity, family size,
family socioeconomic status, and family living standards); family functioning
(quality of early parent-child interactions, frequency of parental change,
parental conflict, and frequency of adverse family life events); and parental
adjustment (parental illicit drug use, parental history of criminal offending,
and parental history of alcoholism or problems with alcohol). These comparisons
showed that with respect to most of these measures, the GLB and control groups
had similar social, family, and childhood backgrounds. However, the 2 groups
were distinguished from each other by 2 factors: GLB youth tended to have
experienced a higher rate of parental change during childhood (P=.007),
and GLB youth were more likely to have parents with a history of criminal
offending (P=.026) than the control group. The way in which these
comparison variables were measured is described below.
As part of the study,
comprehensive information on changes of parents was collected at annual
intervals throughout childhood.26
This information was used to construct a measure of the number of changes of
parents the child had experienced from birth to age 14 years. A change of
parents was counted if a parent left the family as a result of parental
separation, divorce, or death, or a parent entered the family as a result of
remarriage or reconciliation, or the child had experienced any other change of
custodial parents (eg, was placed with foster parents).
When cohort members were
aged 15 years, their parents were questioned concerning parental history of
involvement in (self-defined) criminal offense. On the basis of this
questioning, 12.1% of the sample were classified as having a parental history of
criminality. At each point of interview, signed consent was obtained from
respondents indicating their willingness to participate in the study, and for
all data collection, ethical consent was provided by the local ethics committee.
STATISTICAL ANALYSIS
The statistical analysis was conducted in 2 stages. In the first stage,
estimates of the odds ratios (ORs) between the sexual orientation measure (GLB
vs control group) and each dichotomous mental health outcome were computed.27
These associations were tested for statistical significance using the
2
test of independence, and the precision of the estimate was measured by the 95%
confidence interval.
In the second stage of the
analysis, the associations between sexual orientation and mental health outcome
measures were adjusted for potentially confounding differences (parental change
and parental history of criminal offense) between the groups. This was achieved
by fitting a logistic regression model in which the log odds of each mental
health outcome was modeled as a linear function of sexual orientation and the
covariate factors. From the fitted logistic regression model, estimates of the
covariate adjusted rates of each mental health outcome, the covariate adjusted
OR, and the 95% confidence interval were obtained.27,
28 The
significance of the adjusted association was assessed using the log likelihood
ratio
2
test. All regression models were tested for the presence of interactive
relationships, and no significant interactions were found. Owing to the
relatively small number of subjects who met the criteria outlined above for GLB,
the statistical power of this study was relatively low. Power calculations
showed that the sample had 80% power (
=.05) to
detect an OR of 3.5 or greater for any outcome for which there was a 25%
prevalence.
RESULTS
The GLB subjects had consistently higher rates of all outcomes analyzed in comparison with other cohort members (Table 1). In 7 of 8 comparisons, these differences were statistically significant (P<.05, exact values are presented in Table 1); and in one (substance abuse and/or dependence), nonsignificant (P=.086). Odds ratios between sexual orientation and the outcome measures ranged from 1.9 to 6.2 with a median value of 4.5. The weight of the evidence clearly favors the view that GLB young people showed pervasive increases in risks of common psychiatric disorders, with these increases being particularly evident for measures of suicidal ideation, suicide attempt, and multiple disorders.
In subsequent analysis we
divided the sample by sex to examine the relationships between sexual
orientation and mental health risks for men and women. Although, because of
small numbers when the sample was divided by sex, it was not possible to conduct
formal tests on the similarity of results for men and women, inspection of the
results suggested that associations between sexual orientation and mental health
were similar for men and women. To examine the extent to which the results were
influenced by the definition of GLB status, we also reanalyzed these data
comparing the 20 subjects who claimed to be of GLB sexual orientation with the
remaining cohort members (excluding the 8 individuals who reported homosexual
experience but claimed to be heterosexual). Associations between GLB status and
mental health were also evident when this definition was employed, with ORs
ranging from 1.9 to 6.9 with a median value of 3.5. These reanalyses clearly
suggest that links between GLB status and mental health risks were present for
both male and female respondents and that the conclusions were robust to changes
in the definition of the GLB sexual orientation.
As noted in the
"Subjects and Methods" section, GLB subjects had experienced more
frequent changes of parents during childhood primarily as a result of parental
separation and/or divorce and remarriage (P=.007) and were more likely to
have had parents with a history of criminal offense (P=.026). To take
account of these differences in the backgrounds of the GLB subjects and other
cohort members, the associations between GLB status and the outcome measures
were adjusted for the potentially confounding effects of parental change and
parental criminality using logistic regression techniques. The results of this
analysis showed that these statistical adjustments had a negligible effect on OR
estimates. After adjustment for confounding factors, ORs ranged from 2.2 to 6.9.
As in Table
1, all associations were statistically significant with the exception of the
measure of other substance abuse and/or dependence.
COMMENT
In this study we have used
data gathered over a 21-year longitudinal study to examine the extent to which
GLB young people are at increased risk of psychiatric disorder and suicidal
behaviors. In confirmation of a growing number of recent studies,1-4
our results suggest the presence of elevated rates of psychiatric disorder and
suicidal behavior among GLB young people, with this group having ORs for these
disorders that ranged from 1.9 to 6.2 times higher than for other cohort
members. Risks of suicidal behavior or multiple disorder were most strongly
related to sexual orientation with ORs for these outcomes being in excess of 5.
These results appeared to apply to both men and women and persisted when
differing definitions of GLB status were applied.
An advantage of the
prospective design used in this research was that it was possible to examine the
extent to which differences between GLB young people and other cohort members
reflected social, family, and other factors that may be associated with sexual
orientation in young adulthood. This analysis revealed few differences in the
social, family, and childhood backgrounds of GLB youth and other cohort members.
Nonetheless, there was some evidence to suggest small tendencies for the GLB
group to have experienced more troubled childhoods, with this group having
greater exposure to parental change including separation and/or divorce and
remarriage and higher exposure to parents with a history of criminal offense.
Statistical control of these potentially confounding factors had little effect
on the associations between sexual orientation and risks of psychiatric
disorder. After controlling for confounding factors, significant associations
remained between GLB status and 7 of 8 outcome measures, with estimates of the
adjusted ORs that were generally similar to, or slightly higher than, the
corresponding unadjusted estimates. These findings add to a growing body of
evidence that suggests increased risks of suicidal behavior and mental health
problems among young people who disclose GLB sexual orientation.
A potential threat to the
validity of this study clearly concerns the accuracy with which respondents
reported their sexual orientation. In particular, it seems likely that not all
subjects would have disclosed their sexual orientation accurately and that this
would have been particularly likely for those facing psychological conflict in
reconciling their sexuality with social, family, or personal expectations. While
the effects of misascertainment of sexual orientation on the results of this
study cannot be fully predicted, it seems reasonable to assume that any bias is
likely to be in the direction of the underestimation of associations rather than
their overestimation. This is because those who were most troubled about their
sexual orientation would have also been most likely not to report that they were
GLB. In future studies, we hope to examine this issue by reinterviewing the
cohort at age 25 years to examine the stability of the reporting of sexual
orientation over time and the extent to which associations between GLB sexual
orientation and psychiatric risk vary with age.
The rate of GLB young
people in this cohort (2.8%) is lower than that reported by some authors who
have suggested that up to 15% of youth may experience sexual attraction to
members of the same sex.9
However, this may be explained by the fact that in the present study, we have
employed a relatively stringent criterion that required that the young person
either self-identified as being of GLB sexual orientation or reported sexual
relationships with a same-sex partner. In contrast, studies reporting higher
prevalence rates have employed measures of same-sex attraction, irrespective of
the respondent's reported sexual orientation or sexual experience. The advantage
of the stringent definition used in this study is that it avoids the ambiguities
of interpreting reports of same-sex attraction but has the potential
disadvantage of underestimating the fraction of the population who may
experience some degree of homosexual attraction. Furthermore the prevalence of
same-sex sexual contact found in this study (2.4%) appears to fall within the
range of estimates of same-sex sexual contact found in population studies in the
United States and Great Britain, with these studies reporting estimates that
range from 2.1% to 6.2%.29,
30
Irrespective of these issues of definition, measurement, and reporting, the
present study shows that young people who disclose same-sex sexual contact are
at clearly increased risks of psychiatric disorder and suicidal behaviors.
While there is an emerging
consensus from recent studies that young people who disclose homosexual
behaviors or attraction are at increased risk of suicidal behaviors and mental
health problems, the processes that lead to these associations remain unclear.
Although such findings are frequently interpreted as suggesting the role of
homophobic attitudes and social prejudice in provoking mental health problems in
GLB youth, alternative explanations are possible. These include (1) the
possibility that associations are artifactual as a result of measurement and
other research design problems, (2) the possibility of "reverse
causality" in which young people prone to psychiatric disorder are more
prone to experience homosexual attraction or contact, and (3) the possibility
that lifestyle choices made by GLB young people place them at greater risk of
adverse life events and stresses that increase risks of mental health problems,
independently of GLB sexual orientation. More generally, while recent research
has established the presence of consistent and replicable associations between
GLB sexual orientation and psychiatric risk, the extent to which these
associations reflect the consequences of social discrimination or the extent to
which these associations can be explained in other ways remains to be
established.
Author/Article Information
From the Christchurch Health and Development Study (Dr Fergusson and Mr Horwood) and the Canterbury Suicide Project (Dr Beautrais), Christchurch School of Medicine, New Zealand.
Corresponding author: David Fergusson, PhD, Christchurch Health and Development Study, Christchurch School of Medicine, PO Box 4345, Christchurch, New Zealand (e-mail: david.fergusson@chmeds.ac.nz).
Accepted for publication June 8, 1999.
This research was funded
by grants from the Health Research Council of New Zealand, and the National
Child Health Research Foundation, Auckland; the Canterbury Medical Research
Foundation, Christchurch; and the New Zealand Lottery Grants Board, Wellington,
New Zealand.
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