Attention-deficit/hyperactivity disorder and suicide: A systematic review

Table 3 Included relevant articles examining attention-deficit/hyperactivity disorder and suicidality from January 2011 to January 2015: Suicidality in patients with psychiatric disorders who have attention-deficit/hyperactivity disorder comorbidity

Suicidality in patients with psychiatric disorders who have ADHD comorbidity
Ref.	Country	Study design	Sample	Population at onset	Population’s age at onset	Measures for ADHD, comorbid conditions and suicidality	Main findings
Bácskai et al[41]	Hungary	Cross-sectional	Clinical sample	198 patients with drug dependence (male ratio: 76%) Drug dependent patients without ADHD: n = 154 Drug dependent patients with ADHD: n = 44	Age range: 18-40 yr Mean age of the whole sample: 27 yr (SD = 6.31)	ASRS, EuroADAD, BDI	Drug dependent patients with ADHD showed a significantly higher proportion of suicidal ideation, suicidal attempts and self-injuries associated with suicidal attempts than drug dependent patients without ADHD
Berkol et al[42]	Turkey	Cross-sectional	Clinical sample	Patients with BD type I and II Adult BP with ADHD: n = 23 Adult BP without ADHD: n = 32	BP adults with ADHD: Mean age: 35.1 yr (SD = 10.7) BP adults without ADHD: Mean age: 41.3 yr (SD = 13.0)	ADHD scale Mood disorder modul of SCID-I-CV	In the BP with ADHD group, the rate of suicide attempts (47.8%) was significantly higher than in the BP without ADHD group (21.9%)
Donev et al[43]	Germany	Cross-sectional	Clinical sample	Patients with schizophrenia according to ICD-10 criteria: n = 27 (14 male) Patients with schizophrenia and no ADHD: n = 15 Patients with schizophrenia and ADHD: n = 12	Age range: 18-44 yr Mean age: 25.7 yr (SD = 7.6)	ADHD-HKS Questionnaire	Among patients with both schizophrenia and ADHD there were significantly higher number of suicide attempts than among those with schizophrenia without ADHD
Huntley et al[31]	United Kingdom	Cross-sectional	Clinical sample	Participants from two in-patient alcohol and drug detoxification units: n = 226 (male ratio: 76.5%) Patient with alcohol/drug intoxication + ADHD: n = 11 Patient with alcohol/drug intoxication without ADHD: n = 183	Mean age: 39.0 yr (SD = 10.3)	DSM-IV 18-item self-report ADHD screening questionnaires for both current and childhood behavior Impairment questions from the Barkley scales DIVA	Patients with both substance use disorders and ADHD had significantly higher rates of prior suicide attempts than patients with substance use disorder without ADHD
Patros et al[44]	United States	Cross-sectional	Community sample	College students: n = 1056 (male ratio: 38.5%)	Age range: 18 yr of age or older; 96.4% aged 18-24 yr	CSS, HDSQ	Higher hyperactive/attention symptoms were associated with increase in suicidal thoughts, suicide attempts, and need for medical attention after suicide attempts, among participants with depressed mood
Penney et al[45]	Canada	Cross-sectional	Clinical sample	Clients who presented for treatment at an addictions facility: n = 5990 (male ratio: 63.1%) Clients who reported being hospitalized for attempting suicide in the past year: n = 76 All other clients: n = 5914	Age range: 11-86 yr Mean age: 32.60 yr (SD = 14.55)	Clients reported whether or not they had been diagnosed by a mental health professional in the last 12 mo and in heir lifetime	Compared to all other clients, clients who attempted suicide in the past year were significantly more likely to have ADHD (9.2% vs 2.5%)
Sáez-Francàs et al[46]	Spain	Cross-sectional	Clinical sample	Adult CFS patients: n = 158 CFS patients with adult ADHD: n = 33 (male ratio: 3.0%) CFS patients without adult ADHD (male ratio: 6.4%)	CFS + ADHD: Mean age: 47.55 yr (SD = 7.99) CFS: Mean age: 48.60 yr (SD = 8.88)	CAADID Suicide risk was studied with the Plutchick Risk of Suicide Scale (Plutchik et al, 1989), a 15-item self-report scale with dichotomous responses. Values above the cut-off point of 6 indicate a risk of suicide	CFS patients with adult ADHD had a higher risk of suicide than CFS patients without ADHD

CFS: Chronic fatigue syndrome; ADHD: Attention-deficit/hyperactivity disorder; ASRS: Adult Self-Report Scale; EuroADAD: European Version of the Adolescent Assessment Dialogue; BDI: Beck Depression Inventory; SCID-I-CV: Structured Clinical Interview for DSM-IV Axis I Disorders, Clinician Version; DIVA: Diagnostic Interview for ADHD in Adults; CSS: Current Symptoms Scale–Self-Report Form; HDSQ: Hopelessness Depression Symptom Questionnaire-Suicidality Subscale; CAADID: Conners’Adult ADHD Diagnostic Interview for DSM-IV.