The Relationship Between Heart Rate Variability, Psychological Flexibility, and Pain in Neurofibromatosis Type 1.

Individuals with neurofibromatosis type 1 (NF1) and plexiform neurofibromas (PNs) can experience chronic pain. Previous research has examined the relationship between heart rate variability (HRV) and persistent pain. HRV is an index of autonomic nervous system functioning, and reflects the variability in time elapsed between heartbeats. Patients with chronic pain tend to exhibit lower HRV, which has been associated with poor adaptability, or psychological flexibility, to stress. The aim of the current study was to examine relationships between HRV, psychological flexibility, and pain in a sample of adolescents and young adults (AYAs) with NF1 and PNs. AYA participants (n = 40) 16 to 34 years of age with NF1 completed baseline measures of pain and psychological functioning, and underwent a 5-minute electrocardiogram (ECG). A subset of 20 participants completed follow-up questionnaires and a second ECG 8 weeks later. Spectral analyses of ECGs yielded a measure of high-frequency heart rate variability (HF-HRV). Baseline correlations revealed that lower HF-HRV is related to greater inflexibility and more pain interference, but not pain intensity. Moreover, psychological inflexibility significantly mediated the relationship between HF-HRV and pain interference. Finally, regression models indicated that baseline psychological inflexibility is a significant predictor of HF-HRV at follow-up and, separately, that baseline HF-HRV significantly predicted pain intensity at follow-up. These findings suggest complex mind-body processes in the experience of pain in NF1, which have not been studied previously. Implications for pain-related interventions and future research are discussed.

Fatigue in Children With Sickle Cell Disease: Association With Neurocognitive and Social-Emotional Functioning and Quality of Life.

Children with sickle cell disease (SCD) report fatigue in addition to acute and chronic pain, which can decrease overall health-related quality of life (HRQL). The primary objective of the current study was to investigate the relationship between fatigue and HRQL. Given limited prior research, secondary objectives included investigation of associations between fatigue and functional outcomes, including child neurocognitive and social-emotional functioning. Children aged 8 to 16 years (N=32) and a caregiver completed measures of fatigue, HRQL, pain, and neurocognitive and social-emotional functioning. Controlling for pain and number of SCD-related hospitalizations, hierarchical linear regression models were used to determine the impact of child-reported and parent-reported fatigue on child HRQL. Correlational analyses were used to explore the relationship between fatigue and additional child outcomes. Data indicated that children with SCD experience clinically relevant levels of fatigue, which independently predicts lower HRQL. Fatigue was also associated with lower working memory, executive functioning, and higher levels of internalizing symptoms. Given its observed impact on HRQL and relationship to functional outcomes, fatigue may be an important target of clinical, home, or school interventions. This practice may attenuate the burden of fatigue in these patients, and in turn, help improve the quality of life of children living with SCD.

Sluggish cognitive tempo in survivors of pediatric brain tumors.

The presence of neurocognitive late effects in survivors of pediatric brain tumors is well established. However, there remains some debate about how best to conceptualize these deficits. Sluggish cognitive tempo (SCT) is a proposed conceptual framework that has been used to describe a subset of children with ADHD who exhibit a particular profile characterized by lethargy, day dreaming and staring, and poor organization. Previous work has suggested that survivors of leukemia exhibit a similar profile, but it has not yet been examined in survivors of pediatric brain tumors. A sample of 65 survivors of pediatric brain tumors, 25 survivors of leukemia and 50 community controls completed the Child Behavior Checklist, with four items used to measure SCT. Survivors completed additional measures of neurocognitive functioning. Survivors of brain tumors demonstrated significantly greater symptoms of SCT than survivors of leukemia or controls. SCT was associated with attention problems and working memory deficits and the presence of a VP-shunt. Results provided conditional support for the presence of SCT in survivors of brain tumors, with further research needed to determine the clinical utility of the framework.

Working memory training in survivors of pediatric cancer: a randomized pilot study.

OBJECTIVES: Survivors of pediatric brain tumors and acute lymphoblastic leukemia (ALL) are at increased risk for neurocognitive deficits, but few empirically supported treatment options exist. We examined the feasibility and preliminary efficacy of a home-based, computerized working memory training program, CogmedRM, with survivors of childhood cancer. METHODS: Survivors of brain tumors or ALL (n = 20) with identified deficits in attention and/or working memory were randomized to either the success-adapted computer intervention or a non-adaptive, active control condition. Specifically, children in the adaptive condition completed exercises that became more challenging with each correct trial, whereas those in the non-adaptive version trained with exercises that never increased in difficulty. All participants were asked to complete 25 training sessions at home, with weekly, phone-based coaching support. Brief assessments were completed pre-intervention and post-intervention; outcome measures included both performance-based and parent-report measures of working memory and attention. RESULTS: Eighty-five percent of survivors were compliant with the intervention, with no adverse events reported. After controlling for baseline intellectual functioning, survivors who completed the intervention program evidenced significant post-training improvements in their visual working memory and in parent-rated learning problems compared with those in the active control group. No differences in verbal working memory functioning were evident between groups, however. CONCLUSIONS: Home-based, computerized cognitive training demonstrates good feasibility and acceptability in our sample. Children with higher intellectual functioning at baseline appeared to benefit more from the training, although further study is needed to clarify the strength, scope, and particularly the generalizability of potential treatment effects.

Reliability of the Fagerström Test for Nicotine Dependence, Minnesota Nicotine Withdrawal Scale, and Tiffany Questionnaire for Smoking Urges in smokers with and without schizophrenia.

Few studies have examined the psychometrics of smoking-related behavioral measures in schizophrenia and questions have been raised about the applicability to smokers with schizophrenia. We examined the reliability of the Fagerström Test for Nicotine Dependence (FTND), Minnesota Nicotine Withdrawal Scale (M-NWS), and the Tiffany Questionnaire for Smoking Urges (TQSU) for smokers with schizophrenia (SS; n=151) and nonpsychiatric smokers (CS; n=181) recruited into three studies with similar inclusion criteria. SS and CS did not differ on a number of demographic and smoking variables (e.g., age). SS reported higher carbon monoxide (CO) levels, plasma cotinine levels, FTND, M-NWS, and TQSU Factor 1 scores. The internal consistencies (Cronbach's alpha) of the smoking measures were found to be high and comparable between diagnostic groups for the FTND, M-NWS total scores, and TQSU Factor 2 (all alpha's>0.70) but higher for the CS than SS for the TQSU Factor 1 (0.86 versus 0.79). Test-retest correlations were lower for SS than CS on the FTND (0.65 versus 0.82), TQSU Factor 1 (0.65 versus 0.79), and TQSU Factor 2 (0.69 versus 0.81), but did not differ between diagnostic groups for M-NWS (0.58 versus 0.64). Our findings suggest that these measures may be reliable for use in smokers with schizophrenia.

[Formula: see text]Executive functioning and health-related quality of life in pediatric sickle cell disease.

Research consistently indicates that children with sickle cell disease (SCD) face multiple risk factors for neurocognitive impairment. Despite this, no empirical research to date has examined the impact of neurocognitive functioning on quality of life for this pediatric group. Thus, the current study aims to examine the relationship between executive functioning and quality of life in a sample of children with SCD and further explore psychosocial and family/caregiver resources as moderators of this relationship. A total of 45 children with SCD aged 8 to 16 years and their caregivers completed measures of quality of life, behavioral ratings of executive functioning, and psychosocial functioning. Hierarchical linear regression models were utilized to determine the impact of executive functioning on quality of life and further test the interaction effects of proposed moderating variables. Controlling for age, pain, and socioeconomic status (SES), executive functioning was found to significantly predict child- and parent-reported quality of life among youth with SCD. Psychosocial resources of the primary caregiver or family was not found to moderate the relationship between executive functioning and quality of life. These results provide the first empirical evidence that lower executive skills negatively predict quality of life for children with SCD, supporting clinical and research efforts which aim to establish efficacious interventions that target cognitive decrements within this pediatric population.

A preliminary study of the effects of cigarette smoking on prepulse inhibition in schizophrenia: involvement of nicotinic receptor mechanisms.

BACKGROUND: Schizophrenics exhibit deficits in prepulse inhibition (PPI) of the startle response, and have high rates of cigarette smoking. We evaluated the effects of cigarette smoking on PPI deficits in schizophrenia, and the role of nicotinic acetylcholine receptors (nAChRs) in mediating cigarette smoking-related PPI enhancement. METHODS: PPI was assessed at baseline, after overnight abstinence, and after smoking reinstatement during three separate test weeks in nicotine-dependent schizophrenia (n=15) and control (n=14) smokers pre-treated with the nAChR antagonist mecamylamine (MEC; 0.0, 5.0 or 10.0 mg/day). RESULTS: PPI was comparable between schizophrenia and control smokers after ad lib cigarette smoking. Overnight smoking abstinence significantly reduced PPI, while smoking reinstatement reversed abstinence-induced worsening of PPI deficits in schizophrenia. However, acute abstinence and reinstatement did not alter PPI in controls. PPI enhancement by smoking reinstatement in schizophrenia was dose-dependently blocked by MEC, whereas MEC had no effect on PPI in control smokers. CONCLUSIONS: These results suggest that: 1) Non-deprived smokers with schizophrenia have comparable levels of PPI to non-deprived smoking controls; 2) In schizophrenia, PPI is impaired by smoking abstinence and improved by acute smoking reinstatement, and; 3) enhancement of PPI by cigarette smoking in schizophrenia is mediated by stimulation of central nAChRs. Our findings may contribute to understanding the increased vulnerability to nicotine dependence in schizophrenia, with implications for treatment of PPI deficits in this disorder.

Neuropsychological deficits in nonsmokers with schizophrenia: effects of a nicotinic antagonist.

BACKGROUND: Biochemical, physiological and genetic evidence suggests dysregulation of central nicotinic acetylcholine receptor (nAChR) systems in schizophrenia, which may contribute to neuropsychological dysfunction and the high rates of smoking in this disorder. To evaluate the effects of nAChR blockade on neuropsychological performance in schizophrenia without the confounding effects of cigarette smoking, we compared neuropsychological performance in schizophrenia and healthy control nonsmokers after pre-treatment with the centrally-acting nAChR antagonist mecamylamine (MEC). METHODS: Using a within-subjects, counterbalanced design, schizophrenia (n = 14) and control (n = 15) nonsmokers were pre-treated for 3 days with MEC (0.0, 5.0, and 10.0 mg/day). Subjects performed repeated neuropsychological assessments including visuospatial working memory (VSWM), Continuous Performance Test (CPT), Wisconsin Card Sorting Test (WCST), Word Serial Position Test (WSPT) and Stroop Color Word Test (SCWT) during three sequential test sessions per week over three test weeks. RESULTS: We found significant main effects of schizophrenia diagnosis on: VSWM 30 and 60 delays (p's < 0.01), CPT (% Hit Rate, Reaction Time, Variability Index; p < 0.01 for all outcomes), WCST (p < 0.01 for all outcomes) and Word Serial Position Test (p < 0.01). However, there were no main effects of repeated test administration (Session) or MEC dose on any of these outcomes, and no significant 3-way (DiagnosisxSessionxMEC dose) interactions. CONCLUSIONS: Our results suggest that there are a broad range of neuropsychological deficits in nonsmokers with schizophrenia. Furthermore, pretreatment with a centrally-acting nAChR antagonist did not alter neuropsychological performance in either nonsmoking patients with schizophrenia or controls.

The potential utility of parent-reported attention screening in survivors of childhood cancer to identify those in need of comprehensive neuropsychological evaluation.

BACKGROUND: Survivors of childhood cancer are at risk for neuropsychological late effects, yet identifying those in need of evaluation and obtaining needed services can be challenging for the medical team. Finding time- and cost-effective screening measures that can be used to identify children in need of evaluation is a clinical priority. Our objective was to investigate the association between parent-rated attention problems and related neuropsychological impairments in childhood cancer survivors as a means of identifying those at high risk for difficulties. METHODS: Cognitive and psychosocial data of survivors who completed neuropsychological evaluations were retrospectively abstracted. Parents of 70 survivors of pediatric cancer (mean age, 11.6 years) completed the Conners Parent Rating Scale and the Child Behavior Checklist. Children also completed a measure of intellectual functioning. The 18 symptoms of inattention and hyperactivity were abstracted from the Conners questionnaire, and participants were classified according to whether or not they met attention deficit/hyperactivity disorder (ADHD) symptom criteria (≥6 inattentive symptoms). RESULTS: Survivors who met symptom criteria for ADHD (27%) demonstrated greater impairments in IQ and working memory, but not processing speed, than survivors who did not. Meeting ADHD symptom criteria was also associated with greater externalizing and social problems but not more internalizing symptoms. ADHD symptom screening was associated with low sensitivity (range = 26.3%-69.2%) but stronger specificity (range = 75.0%-82.7%) for neuropsychological difficulties. CONCLUSION: Parental ratings of attentional symptoms may be a useful way to screen survivors who may be in need of a full neuropsychological assessment.

Prefrontal cognitive dysfunction is associated with tobacco dependence treatment failure in smokers with schizophrenia.

BACKGROUND: Patients with schizophrenia have higher rates of smoking (58-88%) than in the general population ( approximately 22%), and are more refractory to smoking cessation. These patients also exhibit numerous neurocognitive deficits, some of which may be ameliorated by cigarette smoking. The neurocognitive benefits derived from nicotine may, in turn, contribute to elevated rates of smoking and smoking persistence in schizophrenia. The present study examined the relationship between neurocognitive function and smoking cessation in schizophrenia. METHODS: Treatment-seeking smokers with schizophrenia (N=58) participated in a 10-week placebo-controlled trial of sustained-release (SR) bupropion plus transdermal nicotine patch. Neuropsychological performance was evaluated in a subset of patients (n=31), prior to pharmacological treatment, using a neurocognitive battery. RESULTS: Subjects were compared as a function of endpoint smoking status (Quit versus Not Quit), assessed by end of trial 7-day point prevalence abstinence, confirmed by CO level (< 10 ppm) on demographic traits, smoking, and clinical outcomes. While there were no significant baseline differences between quitters and non-quitters, non-quitters exhibited significantly greater deficits in performance on Trail Making Test, Part B (p=0.01) and on Digit Span backwards (p=0.04) compared to quitters. No associations were found between quit status and performance on other neuropsychological measures. CONCLUSIONS: Our findings extend results of previous studies which suggest deficits in frontal executive function are associated with smoking cessation failure in schizophrenia. This may have implications for the development of tailored smoking cessation treatments in this population.

A placebo-controlled trial of bupropion combined with nicotine patch for smoking cessation in schizophrenia.

BACKGROUND: Individuals with schizophrenia smoke at higher rates (58%-88%) than the general population (approximately 22%), and have difficulty quitting. We determined whether the combination of sustained-release (SR) bupropion (BUP) with the transdermal nicotine patch (TNP) was well-tolerated and superior to placebo (PLO)+TNP for smoking cessation in schizophrenia. METHODS: A 10-week, double-blind, placebo-controlled trial of BUP (300 mg/day) in combination with TNP (21 mg/24h) for 58 outpatient smokers with schizophrenia was conducted. Primary outcome measures were continuous smoking abstinence in the last 4 weeks of the trial (Days 43-70) and 7-day point prevalence abstinence at 6 months post-target quit date (TQD) (week 26). RESULTS: Smokers assigned to the BUP+TNP group (n = 29) were more likely to achieve continuous smoking abstinence (8/29, 27.6%) than the PLO+TNP group (n = 29, 1/29, 3.4%) [Fisher's Exact Test, p < .05]; at 6-months post-TQD, 4/29 (13.8%) versus 0/29 (0.0%) achieved 7-day point prevalence smoking abstinence (p = .11). Neither bupropion SR nor smoking abstinence significantly altered the positive or negative symptoms of schizophrenia. The combination was well-tolerated in smokers with schizophrenia. CONCLUSIONS: Combination therapy with bupropion SR+TNP versus placebo+TNP is well-tolerated and significantly improved short-term smoking abstinence in smokers with schizophrenia.