How Do Psychiatric Comorbidities Affect Risk of Premature Death Among Children and Adults with ADHD?

Stephen V. Faraone, PhD on August 6, 2019

The Nordic countries maintain detailed registers of their inhabitants. This enables researchers to examine patterns over entire nations. An international research team used the Swedish national registers for a prospective cohort study of 2,675,615 persons in the Medical Birth Register born in Sweden over a 27-year period from January 1, 1983 through December 31, 2009. Follow-up was completed in December 2013, with the oldest cohort member aged 31. The mean age at study entry was 6, and the mean at follow-up was 11.

Using personal identification numbers, researchers were able to cross-reference with the National Patient Register and the National Drug Register. From this they determined that 86,670 members of the cohort (3.2 percent) had ADHD, based either on records of clinical diagnosis or of prescription of ADHD drugs. Psychiatric comorbidities were likewise identified in the National Patient Register.

These comorbidities were significantly more prevalent in the ADHD population than in the rest of the cohort. For example, whereas only 2.2% of the non-ADHD group was diagnosed with substance use disorder (SUD), 13.3% of the ADHD group also had SUD, a six-fold difference. For depression it was a seven-fold difference, for schizophrenia a nine-fold difference.

The ADHD group had a significantly higher risk of premature death from all causes than the non-ADHD group, with an adjusted hazard ratio (HR) of 3.94 (95% CI 3.51-4.43). Unintentional injury (36%) and suicide (31%) were the leading causes of death in the ADHD group. Those with ADHD were more than eight times more likely to die by suicide than non-ADHD individuals, and roughly four times more likely to die from unintentional injury.

The vast majority of the increased risk appears to be associated with comorbid psychiatric conditions. Those with ADHD but no diagnosed comorbidities had an adjusted HR of 1.41 (95% CI 1.01-1.97). With a single comorbidity, the HR more than doubled to 3.71 (95% CI 2.88-4.78). With four or more comorbidities, it rose to a staggering 25.22 (95% CI 19.6-32.46).

The comorbid condition with the greatest impact was SUD, which increased the risk eight-fold by comparison with those with only ADHD (HR = 8.01, 95% CI 6.16-10.41). Anxiety disorder, schizophrenia, and personality disorder increased the risk about fourfold. Bipolar disorder, depression, and eating disorder increased risk roughly two and a half times.

Covariate analysis helped tease out what portion of the risk was associated with ADHD alone versus comorbid conditions. Adjusting for year of birth, sex, birth weight, maternal age at birth, parental educational level, and parental employment status, those with ADHD (including comorbid conditions) were 2.7 times more likely to prematurely die of natural causes than those without. Adjusting for comorbid psychiatric conditions completely eliminated the risk from ADHD alone (HR = 1.01, 95% CI .72-1.42).

Likewise, those with ADHD (including comorbid conditions) were six times as likely to die of unnatural causes. Adjusting for early-onset comorbid disorders (such as conduct disorders, autism spectrum disorder, and intellectual disability) only modestly reduced the HR to 5.3, but further adjusting for later-onset comorbid disorders (including substance use disorder, depressive disorder, bipolar disorder, anxiety disorder, schizophrenia, personality disorder, and eating disorders) reduced the HR to 1.57 (95% CI 1.35-1.83), and reduced it to insignificance in the case of suicide (HR = 1.13, 95% CI .88-1.45).

Summing up, the lion’s share of the greater risk of premature death in persons with ADHD is attributable to psychiatric comorbidities. Nevertheless, those with ADHD alone still face a 40 percent greater risk than those without ADHD.

The study did not examine effects of ADHD medication, which the authors state “should be analyzed because of documented potential benefits on ADHD symptoms and comorbid disorders.”

The authors concluded, “Among adults, early-onset psychiatric comorbidity contributed substantially to the premature mortality risks due to natural causes. On the other hand, later-onset psychiatric comorbidity, especially SUD, explained a substantial part of the risk for unnatural deaths, including all the risk of suicide deaths and most of the deaths due to unintentional injuries. These results suggest that overall health conditions and risk of psychiatric comorbidity should be evaluated clinically to identify high-risk groups among individuals with ADHD.”

REFERENCES:
Shihua Sun, MD; Ralf Kuja-Halkola, PhD; Stephen V. Faraone, PhD; Brian M. D’Onofrio, PhD; Søren Dalsgaard, PhD; Zheng Chang, PhD; Henrik Larsson, PhD, “Association of Psychiatric Comorbidity With the Risk of Premature Death Among Children and Adults With Attention-Deficit/Hyperactivity Disorder,” JAMA Psychiatry doi:10.1001/jamapsychiatry.2019.1944 Published online August 7, 2019.

African American Adults with ADHD – Cultural Barriers and Reduced Access to Care

Anthony L. Rostain, MD MA on March 24, 2016

Clin Psychiatry. 2015; 76(3):279-283.
“Cultural Background and Barriers to Mental Health Care for African American Adults”
Rostain, A.L., Ramsay, J.R., Waite, R.

This article delineates key patient and provider cultural biases that interfere with access to care for African American Adults with ADHD. It provides an important framework for understanding how these biases come about and what clinicians can do to address them. A brief review of the relationship between psychiatry and African Americans points out that beginning with slavery and continuing through the Tuskegee experiment, there is a legacy of racism in American medicine that influences the way patients view health care providers (and vice versa).

For instance, drapetomania was a clinical diagnosis given to slaves who demonstrated resistance to the institution by running away, refusing to follow rules, destroying property and fighting the plantation slave owners. In this fashion, psychiatry played an important role in supporting racism and racist beliefs. Similar analogies can be made to the ways that psychiatry classified homosexuality as a mental illness.

 

The point of this historical review is to underscore the longstanding mistrust that exists within the African American community toward medicine in general and psychiatry in particular. Add to this, the stigma associated with mental illness and substance abuse, it becomes easier to understand why many African American adults fail to seek treatment for disorders like ADHD.

The article goes on to discuss barriers to obtaining mental health treatment including patient factors (e.g. low income, lack of health insurance, fear and other negative attitudes) and health care system factors (e.g. limited access to culturally and technically competent providers and provider biases). Without question, higher rates of poverty and of lack of insurance among the minority population leads to markedly reduced access to care. The article points out that whereas rates of adequate mental health treatment among whites is 33%, the figure drops to 12% for African Americans. Moreover. white 
children are twice as likely to receive ADHD medication as African American children. Cultural biases among providers may lead them to be insufficiently attuned to the presence of ADHD in adult patients, ascribing the symptoms of ADHD, such as inattention, restlessness and disorganization either to personal failing (e.g. lack of self-discipline) or to environmental factors (e.g. low SES, lack of education) rather than to the influence of ADHD.

The paper concludes with practical recommendations for clinicians to address these barriers including providing accurate science based information, listening and being sensitive to stigmatizing experiences that African American patients may have encountered, and recognizing the deleterious effects of conscious and unconscious biases among well-meaning providers.

ADHD and Suicide

Stephen V. Faraone, PhD on March 17, 2016

Suicide is one of the most feared outcomes of any psychiatric condition.  Although its association with depression is well known, a small but growing research literature shows that ADHD is also a risk factor for suicidality.  

Suicide is difficult to study. Because it is relatively rare, large samples of patients are needed to make definitive statements.  Studies of suicide and ADHD must also consider the possibility that medications might elevate that risk. 

For example, the FDA placed a black box warning on atomoxetine because that ADHD medication had been shown to increase suicidal risk in youth.   A recent study of 37,936 patients with ADHD now provides much insight into these issues (Chen, Q., Sjolander, A., Runeson, B., D’Onofrio, B. M., Lichtenstein, P. & Larsson, H. (2014). Drug treatment for attention-deficit/hyperactivity disorder and suicidal behaviour: register based study. BMJ 348, g3769.).    In Sweden, such large studies are possible because researchers have computerized medical registers that describe the disorders and treatments of all people in Sweden.  Among 37,936 patients with ADHD, 7019 suicide attempts or completed suicides occurred during 150,721 person years of follow-up.  This indicates that, in any given year, the risk for a suicidal event is about 5%. 

For ADHD patients, the risk for a suicide event is about 30% greater than for non-ADHD patients.  Among the ADHD patients who attempted or completed suicide, the risk was increased for those who had also been diagnosed with a mood disorder, conduct disorder, substance abuse or borderline personality.  This is not surprising; the most serious and complicated cases of ADHD are those that have the greatest risk for suicidal events.  

The effects of medication were less clear.   The risk for suicide events was greater for ADHD patients who had been treated with non-stimulant medication compared with those who had not been treated with non-stimulant medication.  A similar comparison showed no effect of stimulant medications. 

This first analysis suffers from the fact that the probability of receiving medication increases with the severity of the disorder.  To address this problem, the researchers limited the analyses to ADHD patients who had had some medication treatment and then compared suicidal risk between periods of medication treatment and periods of no medication treatment.  This analysis found no increased risk for suicide from non-stimulant medications and, more importantly, found that for patients treated with stimulants, the risk for suicide was lower when they were taking stimulant medications.  This protective effect of stimulant medication provides further evidence of the long-term effects of stimulant medications which have also been shown to lower the risks for traffic accidents, criminality, smoking and other substance use disorders.