Risk factors for adverse driving outcomes in Dutch adults with ADHD and controls.

OBJECTIVE: To identify risk factors for adverse driving outcomes and unsafe driving among adults with and without ADHD in a Dutch sample. METHODS: In this cross-sectional study, validated self-report questionnaires were used to compare driving history and current driving behavior between 330 adults diagnosed with ADHD and 330 controls. RESULTS: Adults with ADHD had significantly more adverse driving outcomes when compared to controls. Having an ADHD diagnosis significantly increased the odds for having had 3 or more vehicular crashes (OR = 2.72; p = .001). Driving frequency, male gender, age, high anxiety levels, high hostility levels, and alcohol use all significantly influenced the odds for unsafe driving behavior, for having had 12 or more traffic citations, and/or for having had 3 or more vehicular crashes. CONCLUSIONS: Alcohol use, and high levels of anxiety and hostility are highly prevalent among adults with ADHD, and they mediate the risk for negative driving outcomes in this group.

The Association Between Metabolic Syndrome, Obesity-Related Outcomes, and ADHD in Adults With Comorbid Affective Disorders.

OBJECTIVE: ADHD may predispose to obesity, a metabolic syndrome component. Affective disorders are also associated with MetSyn and ADHD. This study examined whether ADHD confers any added risk of MetSyn and obesity-related associations in a large sample with varying stages of affective disorders. METHOD: Participants included 2,303 adults from the Netherlands Study of Depression and Anxiety. Three groups were compared (controls, those with depressive/anxiety disorders without ADHD; and those with depressive/anxiety disorders and ADHD) for presence of MetSyn risk factors, body mass index, and waist-hip ratio. ADHD symptoms were identified by using a T-score > 65 (Conners Adult ADHD Rating Scale). RESULTS: Multivariable analyses were additionally adjusted for sociodemographic, lifestyle, health factors, and affective disorders. Analyses showed no significant association between MetSyn, obesity-related variables, and comorbid ADHD. High Inattention and Hyperactivity/Impulsivity symptoms were not associated with MetSyn. CONCLUSION: This study did not confirm that MetSyn and obesity-related parameters are increased in comorbid ADHD.

ADHD, circadian rhythms and seasonality.

OBJECTIVE: We evaluated whether the association between Adult Attention-Deficit/Hyperactivity Disorder (ADHD) and Seasonal Affective Disorder (SAD) was mediated by the circadian rhythm. METHOD: Data of 2239 persons from the Netherlands Study of Depression and Anxiety (NESDA) were used. Two groups were compared: with clinically significant ADHD symptoms (N = 175) and with No ADHD symptoms (N = 2064). Sleep parameters were sleep-onset and offset times, mid sleep and sleep duration from the Munich Chronotype Questionnaire. We identified the prevalence of probable SAD and subsyndromal SAD using the Seasonal Pattern Assessment Questionnaire (SPAQ). Clinically significant ADHD symptoms were identified by using a T score>65 on the Conners Adult ADHD Rating Scale. RESULTS: The prevalence of probable SAD was estimated at 9.9% in the ADHD group (vs. 3.3% in the No ADHD group) and of probable s-SAD at 12.5% in the ADHD group (vs 4.6% in the No ADHD group). Regression analyses showed consistently significant associations between ADHD symptoms and probable SAD, even after adjustment for current depression and anxiety, age, sex, education, use of antidepressants and benzodiazepines (B = 1.81, p < 0.001). Late self-reported sleep onset was an important mediator in the significant relationship between ADHD symptoms and probable SAD, even after correction for confounders (total model effects: B = 0.14, p ≤ 0.001). CONCLUSION: Both seasonal and circadian rhythm disturbances are significantly associated with ADHD symptoms. Delayed sleep onset time in ADHD may explain the increase in SAD symptoms. Treating patients with SAD for possible ADHD and delayed sleep onset time may reduce symptom severity in these complex patients.

Prevalence of ADHD symptoms across clinical stages of major depressive disorder.

BACKGROUND: Depression and ADHD often co-occur in clinical samples. Depression severity may be linked to ADHD symptomatology. We therefore assessed ADHD symptoms across clinical stages of major depressive disorder (MDD). METHODS: We used 4-year follow-up data of the Netherlands Study of Depression and Anxiety (September 2008 until April 2011), including healthy controls, groups with remitted and current MDD (N=2053; age range 21-69 years; 66.8% females). Probable ADHD was defined as having current ADHD symptoms on the Conners Adult ADHD Rating Scale and a positive score on childhood or early-adolescent ADHD indicators. We examined ADHD symptom rates across (i) those with and without lifetime MDD, (ii) clinical characteristics of MDD including severity, course and outcomes, (iii) clinical stages of MDD. RESULTS: (i) The prevalence of ADHD symptoms was 0.4% in healthy controls, 5.7% in remitted MDD and 22.1% in current MDD (OR=4.5; 95% CI 3.1-6.5). (ii) ADHD symptom rates and odds were significantly increased among those with more severe depression (29.4%; OR=6.8; 95% CI 2.9-16.1), chronic depression (21.8%; OR=3.8; 95% CI 2.5-5.7), earlier age of onset of depressive symptoms (9.9%; OR=1.5; 95% CI 1.0-2.3), and comorbid anxiety disorders (29.0%; OR=3.4; 95% CI 2.0-5.7). (iii) ADHD symptom rates increased across clinical stages of MDD, up to 22.5% in chronic MDD. LIMITATIONS: We used self-reports on ADHD symptoms. Also, clinical staging models have not yet been validated for mental disorders. CONCLUSIONS: ADHD symptoms are very common among MDD patients, especially among those in recurrent and chronic stages of MDD. Considering ADHD may be an important step forward in improving the treatment of depression.

Circadian rhythm disruption as a link between Attention-Deficit/Hyperactivity Disorder and obesity?

OBJECTIVE: Patients with Attention-Deficit/Hyperactivity Disorder (ADHD) have a high prevalence of obesity. This is the first study to investigate whether circadian rhythm disruption is a mechanism linking ADHD symptoms to obesity. METHODS: ADHD symptoms and two manifestations of circadian rhythm disruption: sleep problems and an unstable eating pattern (skipping breakfast and binge eating later in the day) were assessed in participants with obesity (n= 114), controls (n= 154), and adult ADHD patients (n= 202). RESULTS: Participants with obesity had a higher prevalence of ADHD symptoms and short sleep on free days as compared to controls, but a lower prevalence of ADHD symptoms, short sleep on free days, and an unstable eating pattern as compared to ADHD patients.We found that participants with obesity had a similar prevalence rate of an unstable eating pattern when compared to controls. Moreover, mediation analyses showed that both sleep duration and an unstable eating pattern mediated the association between ADHD symptoms and body mass index (BMI). CONCLUSION: Our study supports the hypothesis that circadian rhythm disruption is a mechanism linking ADHD symptoms to obesity. Further research is needed to determine if treatment of ADHD and circadian rhythm disruption is effective in the prevention and treatment of obesity in patients with obesity and/or ADHD.

OROS-methylphenidate efficacy on specific executive functioning deficits in adults with ADHD: a randomized, placebo-controlled cross-over study.

Attention-deficit/hyperactivity disorder (ADHD) is linked to impaired executive functioning (EF). This is the first study to objectively investigate the effects of a long-acting methylphenidate on neurocognitive test performance of adults with ADHD. Twenty-two adults with ADHD participated in a 6-weeks study examining the effect of osmotic-release oral system methylphenidate (OROS-mph) on continuous performance tests (CPTs; objective measures), and on the self-reported ADHD rating scale (subjective measure) using a randomized, double-blind, placebo-controlled cross-over design. OROS-mph significantly improved reaction time variability (RTV), commission errors (CE) and d-prime (DP) as compared to baseline (Cohen's d>.50), but did not affect hit reaction time (HRT) or omission errors (OE). Compared to placebo, OROS-mph only significantly influenced RTV on one of two CPTs (p<.050). Linear regression analyses showed predictive ability of more beneficial OROS-mph effects in ADHD patients with higher EF severity (RTV: ß=.670, t=2.097, p=.042; omission errors (OE): ß=-.098, t=-4.759, p<.001), and with more severe ADHD symptoms (RTV: F=6.363, p=.019; HRT: F=3.914, p=.061). Side effects rates were substantially but non-significantly greater for OROS-mph compared to placebo (77% vs. 46%, p=.063). OROS-mph effects indicated RTV as the most sensitive parameter for measuring both neuropsychological and behavioral deficits in adults with ADHD. These findings suggest RTV as an endophenotypic parameter for ADHD symptomatology, and propose CPTs as an objective method for monitoring methylphenidate titration.

Body temperature, activity and melatonin profiles in adults with attention-deficit/hyperactivity disorder and delayed sleep: a case-control study.

Irregular sleep-wake patterns and delayed sleep times are common in adults with attention-deficit/hyperactivity disorder, but mechanisms underlying these problems are unknown. The present case-control study examined whether circadian abnormalities underlie these sleep problems in a naturalistic home setting. We included 12 medication-naïve patients with attention-deficit/hyperactivity disorder and delayed sleep phase syndrome, and 12 matched healthy controls. We examined associations between sleep/wake rhythm in attention-deficit/hyperactivity disorder and circadian parameters (i.e. salivary melatonin concentrations, core and skin temperatures, and activity patterns) of the patients and controls during five consecutive days and nights. Daily bedtimes were more variable within patients compared with controls (F = 8.19, P < 0.001), but melatonin profiles were equally stable within individuals. Dim-light melatonin onset was about 1.5 h later in the patient group (U = 771, Z = -4.63, P < 0.001). Patients slept about 1 h less on nights before work days compared with controls (F = 11.21, P = 0.002). The interval between dim-light melatonin onset and sleep onset was on average 1 h longer in patients compared with controls (U = 1117, Z = -2.62, P = 0.009). This interval was even longer in patients with extremely late chronotype. Melatonin, activity and body temperatures were delayed to comparable degrees in patients. Overall temperatures were lower in patients than controls. Sleep-onset difficulties correlated with greater distal-proximal temperature gradient (DPG; i.e. colder hands, r(2)  = -0.32, P = 0.028) in patients. Observed day-to-day bedtime variability of individuals with attention-deficit/hyperactivity disorder and delayed sleep phase syndrome were not reflected in their melatonin profiles. Irregular sleep-wake patterns and delayed sleep in individuals with attention-deficit/hyperactivity disorder and delayed sleep phase syndrome are associated with delays and dysregulations of the core and skin temperatures.

Long-term relationship between methylphenidate and tobacco consumption and nicotine craving in adults with ADHD in a prospective cohort study.

Patients with Attention-Deficit/Hyperactivity disorder (ADHD) have higher smoking rates, a younger age of smoking onset, and increased difficulty to stop smoking as compared to controls. Methylphenidate induced acute effects of increased smoking in laboratory studies, but long-term effects are unknown. We studied the acute and long-term relationship between methylphenidate use and tobacco consumption and nicotine craving among ADHD patients naïve for methylphenidate (N=325). Patients filled out the Smoking Questionnaire (SQ) at baseline, and after two-weeks and three-months of methylphenidate use. The SQ involved questions on demographics, tobacco consumption, nicotine craving, life events, psychiatric diagnoses and use of medication. At baseline, smoking prevalence of ADHD patients was twice as high (50.2%) as the national norm (25.6%; p<.001). Tobacco consumption increased with 1.3 cigarettes per day after three-months of methylphenidate use. When translated into pack years, tobacco consumption increased by about 23 packs per year. Reports of increased nicotine craving after methylphenidate, increased with 20.3% after two weeks and 29.2% after three months. Light smokers (1-12 cigarettes/day) were especially at risk for increased tobacco consumption (p<.05). Thus although methylphenidate is the drug of choice in medical treatment for ADHD, tobacco consumption and nicotine craving increased acutely and stabilized at increased levels after three-months of methylphenidate use. Although the net effect of methylphenidate on smoking behavior and craving should be further investigated within a randomized, placebo-controlled design, the results suggest that active prevention of increased smoking is needed in patients prescribed methylphenidate.

Development of regulation disorders into specific psychopathology.

Underlying deficits in self-regulation and sensory processing are seen in children with regulation disorders (RD) and might lead to emotional and behavioral problems as the child develops. However, little is known about the specific developmental course of RD. This follow-up study was conducted to investigate the development of a clinical sample of RD children, diagnosed by means of the Diagnostic Classification of Mental Health and Developmental Disorders of Infancy and Early Childhood, Revised (DC:0-3R; ZERO TO THREE, 1994), toward specific psychopathology 4 to 10 years later based on parent- and teacher-reports on the Child Behavior Checklist (T.M. Achenbach & L.A. Rescorla, 2007). Parental reports showed that 39 to 69% of children with RD had internalizing, externalizing, and total problems above borderline cutoffs, as compared to norm group data (16%). In addition, higher rates of affective, anxiety, attention deficit/hyperactivity, oppositional defiant, and conduct problems were reported. Analyses between RD subtypes showed significant differences on future attention problems and rule-breaking behavior, wherein less favorable results were found for the Hypersensitive subtype Type A (fearful/cautious) in comparison to the sensory stimulation-seeking/impulsive subtype. The current results indicate persistence of emotional and behavioral problems into middle childhood and adolescence in children with preschool RD diagnoses. More attention should be paid to differentiation of psychopathology in these children since developmental outcomes may differ between RD subtypes.