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Depression: a family affair
COMMENTARY
Depression: a family affair About 10 years ago a survey by Myrna Weissman and colleagues revealed that major depression and anxiety disorders were commoner among offspring of depressed patients than among children of non-depressed parents.1 The offspring of the depressed patients have recently been re-examined.2 This work might have gone unnoticed had it simply confirmed studies showing that depression is familial and has a genetic component to its complex aetiology.3 Instead, it built upon the earlier survey addressing key clinical issues: the validity of depression as a diagnosis among children, the continuity between child and adult psychiatric disorders, psychiatric comorbidity, and the underidentification and treatment of juvenile depression. Two decades ago a literature review concluded that diagnosing depression in children “would appear to be premature and treatment unwarranted”.4 Because its call for further research has been answered by Weissman and others, current reviews have confidently reversed that conclusion.5 Childhood depression is neither a developmental phase nor a mask for other problems. In the Weissman study, depression was found among prepubertal children, and its peak incidence occurred in adolescence. If childhood depression was a misdiagnosed “developmental phase”, it should have been found in equal numbers among children of nondepressed parents. It was not. Thus, not only do sad parents breed sad children, but the youngest of these are not spared. The transmission of depression from parents to young children bolsters the validity of the diagnosis among children and also supports the idea that childhood depression is an early expression of the well-known adult form of the disorder. Weissman and colleagues found further support for this continuity hypothesis in the follow-up study: 10 years after their initial assessment, compared with the controls, offspring of depressed parents showed greater social impairment and had a three-fold increased risk of depression and phobias as well as a five-fold increased risk of panic disorder and alcohol dependence. This finding confirms a report from the UK that adult mood disorders were found in nearly half of a sample that had been diagnosed as having depression while in childhood.6 If symptoms of depression represented normal responses to development transitions, they should have waxed and waned with development. The concept that depression occurs in childhood was not readily accepted partly because of its comorbidity with other disorders. The 10-year follow-up study by Weissman and colleagues showed that 83% of the depressed high-risk children had either an anxiety or a substance-use disorder. Other studies reporting that depression in childhood is accompanied by conduct disorder and attention-deficit hyperactivity disorder (ADHD) showed that the comorbid disorders usually preceded the onset of major depression by several years.7 Thus, juvenile depression rarely occurs in “pure” form. Because symptoms of depression often come on the heels of another disorder, clinicians have tended to view these symptoms as secondary responses to the social and school failure attributed to the primary disorder. But today, the bulk of research justifies a new clinical maxim: children with anxiety or disruptive behaviour disorders who meet criteria for depression are probably depressed. 158
That diagnosis should be considered and, if confirmed, appropriate treatment implemented. The underidentification of childhood depression has been fuelled not only by psychiatric comorbidity but also by its clinical presentation which, by adult standards, is atypical. Depressed children are commonly irritable, not dysphoric. Their course is usually chronic, not remitting. Although these atypical features complicate differential diagnoses, astute clinicians will not be fooled if they assiduously apply the diagnostic criteria for depression— which include irritability—and do not rule out the diagnosis of depression if the abnormal mood is chronic. Nevertheless, depressed children are still underidentified. Weissman found that a third of the depressed high-risk offspring had not been treated during the follow-up period despite impaired family and work functioning. Epidemiological studies suggest that underidentification is common.8 The implications for clinical practice are enormous. In the long run, the very early identification of children at high risk of depression will enable implementation of preventive measures. Current research will show whether prevention is possible.9 Meanwhile, researchers should be developing cost-effective methods that will enable paediatricians to screen families routinely for mental illness, especially for disorders such as mild anxiety and depression that do not disrupt the child’s environment and hence are not likely to spur parents to seek help. Mental-health professionals who treat depressed adults should inquire about their children and teach parents of these high-risk young people how to recognise depression. And, of course, mental-health clinicians who treat children with ADHD or conduct disorders or anxious children should not routinely dismiss the signs and symptoms of depression as normal responses to a pre-existing disorder. They should consider depression as a viable diagnostic option for the child and should not attribute depression in parents as the expected reaction of dealing with a mentally disordered child. In short, the diagnosis and treatment of depression should be a family affair.
Stephen V Faraone, Joseph Biederman Paediatric Psychopharmacology Unit, Child Psychiatry Ser vice, Massachusetts General Hospital, Harvard Medical School, Boston MA 02114, USA 1
2
3 4 5
6
7
8
9
Weissman MM, Merikangas KR, John K, et al. Family-genetic studies in psychiatric disorders. Arch Gen Psychiatry 1986; 43: 1104–16. Weissman M, Warner V, Wickramaratne P, Moreau D, Olfson M. Offspring of depressed parents: 10 years later. Arch Gen Psychiatry 1997; 54: 932–42. Tsuang MT, Faraone SV. The genetics of mood disorders. Baltimore: John Hopkins University Press, 1990. Lefkowitz MM, Burton N. Childhood depression: a critique of the concept. Psychol Bull 1978; 85: 716–26. Birmaher B, Ryan ND, Williamson DE, Brent DA, Kaufman J. Childhood and adolescent depression: a review of the past 10 years. Part II. J Am Acad Child Adolesc Psychiatry 1996; 35: 1575–83. Harrington R, Fudge H, Rutter M, Pickles A, Hill J. Adult outcomes of childhood and adolescent depression I: psychiatric status. Arch Gen Psychiatry 1990; 47: 463–73. Biederman J, Faraone S, Mick E, Lelon E. Psychiatric comorbidity among referred juveniles with major depression: fact or artifact? J Am Acad Child Adolesc Psychiatry 1995; 34: 579–90. Bird HR, Canino G, Rubio-Stipec M, et al. Estimates of the prevalence of childhood maladjustment in a community survey in Puerto Rico. Arch Gen Psychiatry 1988; 45: 1120–26. Beardslee W, Salt P, Versage E, Gladstone T, Wright E, Rothberg P. Sustained change in parents receiving preventive interventions for families with depression. Am J Psychiatry 1997; 154: 510–15.
THE LANCET • Vol 351 • January 17, 1998
Depression: a family affair About 10 years ago a survey by Myrna Weissman and colleagues revealed that major depression and anxiety disorders were commoner among offspring of depressed patients than among children of non-depressed parents.1 The offspring of the depressed patients have recently been re-examined.2 This work might have gone unnoticed had it simply confirmed studies showing that depression is familial and has a genetic component to its complex aetiology.3 Instead, it built upon the earlier survey addressing key clinical issues: the validity of depression as a diagnosis among children, the continuity between child and adult psychiatric disorders, psychiatric comorbidity, and the underidentification and treatment of juvenile depression. Two decades ago a literature review concluded that diagnosing depression in children “would appear to be premature and treatment unwarranted”.4 Because its call for further research has been answered by Weissman and others, current reviews have confidently reversed that conclusion.5 Childhood depression is neither a developmental phase nor a mask for other problems. In the Weissman study, depression was found among prepubertal children, and its peak incidence occurred in adolescence. If childhood depression was a misdiagnosed “developmental phase”, it should have been found in equal numbers among children of nondepressed parents. It was not. Thus, not only do sad parents breed sad children, but the youngest of these are not spared. The transmission of depression from parents to young children bolsters the validity of the diagnosis among children and also supports the idea that childhood depression is an early expression of the well-known adult form of the disorder. Weissman and colleagues found further support for this continuity hypothesis in the follow-up study: 10 years after their initial assessment, compared with the controls, offspring of depressed parents showed greater social impairment and had a three-fold increased risk of depression and phobias as well as a five-fold increased risk of panic disorder and alcohol dependence. This finding confirms a report from the UK that adult mood disorders were found in nearly half of a sample that had been diagnosed as having depression while in childhood.6 If symptoms of depression represented normal responses to development transitions, they should have waxed and waned with development. The concept that depression occurs in childhood was not readily accepted partly because of its comorbidity with other disorders. The 10-year follow-up study by Weissman and colleagues showed that 83% of the depressed high-risk children had either an anxiety or a substance-use disorder. Other studies reporting that depression in childhood is accompanied by conduct disorder and attention-deficit hyperactivity disorder (ADHD) showed that the comorbid disorders usually preceded the onset of major depression by several years.7 Thus, juvenile depression rarely occurs in “pure” form. Because symptoms of depression often come on the heels of another disorder, clinicians have tended to view these symptoms as secondary responses to the social and school failure attributed to the primary disorder. But today, the bulk of research justifies a new clinical maxim: children with anxiety or disruptive behaviour disorders who meet criteria for depression are probably depressed. 158
That diagnosis should be considered and, if confirmed, appropriate treatment implemented. The underidentification of childhood depression has been fuelled not only by psychiatric comorbidity but also by its clinical presentation which, by adult standards, is atypical. Depressed children are commonly irritable, not dysphoric. Their course is usually chronic, not remitting. Although these atypical features complicate differential diagnoses, astute clinicians will not be fooled if they assiduously apply the diagnostic criteria for depression— which include irritability—and do not rule out the diagnosis of depression if the abnormal mood is chronic. Nevertheless, depressed children are still underidentified. Weissman found that a third of the depressed high-risk offspring had not been treated during the follow-up period despite impaired family and work functioning. Epidemiological studies suggest that underidentification is common.8 The implications for clinical practice are enormous. In the long run, the very early identification of children at high risk of depression will enable implementation of preventive measures. Current research will show whether prevention is possible.9 Meanwhile, researchers should be developing cost-effective methods that will enable paediatricians to screen families routinely for mental illness, especially for disorders such as mild anxiety and depression that do not disrupt the child’s environment and hence are not likely to spur parents to seek help. Mental-health professionals who treat depressed adults should inquire about their children and teach parents of these high-risk young people how to recognise depression. And, of course, mental-health clinicians who treat children with ADHD or conduct disorders or anxious children should not routinely dismiss the signs and symptoms of depression as normal responses to a pre-existing disorder. They should consider depression as a viable diagnostic option for the child and should not attribute depression in parents as the expected reaction of dealing with a mentally disordered child. In short, the diagnosis and treatment of depression should be a family affair.
Stephen V Faraone, Joseph Biederman Paediatric Psychopharmacology Unit, Child Psychiatry Ser vice, Massachusetts General Hospital, Harvard Medical School, Boston MA 02114, USA 1
2
3 4 5
6
7
8
9
Weissman MM, Merikangas KR, John K, et al. Family-genetic studies in psychiatric disorders. Arch Gen Psychiatry 1986; 43: 1104–16. Weissman M, Warner V, Wickramaratne P, Moreau D, Olfson M. Offspring of depressed parents: 10 years later. Arch Gen Psychiatry 1997; 54: 932–42. Tsuang MT, Faraone SV. The genetics of mood disorders. Baltimore: John Hopkins University Press, 1990. Lefkowitz MM, Burton N. Childhood depression: a critique of the concept. Psychol Bull 1978; 85: 716–26. Birmaher B, Ryan ND, Williamson DE, Brent DA, Kaufman J. Childhood and adolescent depression: a review of the past 10 years. Part II. J Am Acad Child Adolesc Psychiatry 1996; 35: 1575–83. Harrington R, Fudge H, Rutter M, Pickles A, Hill J. Adult outcomes of childhood and adolescent depression I: psychiatric status. Arch Gen Psychiatry 1990; 47: 463–73. Biederman J, Faraone S, Mick E, Lelon E. Psychiatric comorbidity among referred juveniles with major depression: fact or artifact? J Am Acad Child Adolesc Psychiatry 1995; 34: 579–90. Bird HR, Canino G, Rubio-Stipec M, et al. Estimates of the prevalence of childhood maladjustment in a community survey in Puerto Rico. Arch Gen Psychiatry 1988; 45: 1120–26. Beardslee W, Salt P, Versage E, Gladstone T, Wright E, Rothberg P. Sustained change in parents receiving preventive interventions for families with depression. Am J Psychiatry 1997; 154: 510–15.
THE LANCET • Vol 351 • January 17, 1998