Clinical applicability of heart rate variability analysis by methods based on nonlinear dynamics

Analysis of heart rate (HR) variability has become an important widely used method for assessingcardiac autonomic regulation. Conventionally, HR variability has been analyzed with time and frequency domainmethods. Analysis of HR dynamics by methods based on nonlinear systems theory has opened a novel approach forstudying the abnormalities in HR behavior. Recent studies have shown that these measures, particularly scalinganalysis methods of HR dynamics, are altered among various patients populations with cardiovascular diseases, andthey provide prognostic information. Altered long-term scaling properties of HR dynamics and more random short-termHR fluctuation has been observed, e.g., among patients with previous myocardial infarction, and these alterationshave been shown to be associated with increased mortality rate. A relatively large body of data indicate thataltered scaling properties of R-R intervals are physiologically deleterious. These findings support the notion thatsome nonlinear methods, such as scaling and complexity measures, give clinically valuable information for riskstratification among various patient populations. This article provides a review of our current knowledge of theusefulness of dynamical measures of HR fluctuation.     

Amplification of fgfr4 gene in human breast and gynecological cancers

We have investigated gene amplification of fibroblast growth factor receptor-4 (FGFR4) gene in 30 primary breast tumor samples and 15 gynecological tumor samples. Ten percent of the breast tumors showed 2- to 4-fold amplification. Amplification was found more frequently in estrogen- and progesterone-receptor-positive tumors and in tumors with high lymph-node involvement. Breast tumor samples were also analyzed for the amplification of fgfr3 and erbB2 genes and the chromosome I Iq 13 located genes hst I Iint2lbci1 /sea. erbB2 gene was amplified 2- to 13-fold in 13% of the cases, but no amplification of int2/hst I/be/1/sea amplicon was found. Gynecological tumors were also analyzed for the amplification of fgfr4 and fgfr3 genes and for int2 and hst I oncogenes. Eleven of the 15 gynecological tumors were ovarian neoplasms including 2 benign tumors; the remainder comprised I ovarian metastasis of breast cancer; I endometrial cancer; I uterine leiomyosarcoma and I carcinosarcoma of the fallopian tube. In gynecological tumors, fgfr4 gene was found to be amplified in 2 ovarian tumors. Amplification of hst I was found in I benign ovarian tumor. Thus, the fgfr4 gene may be involved in breast and ovarian tumorigenesis.     

Accelerated pubertal development in patients with shunted hydrocephalus

OBJECTIVE: To evaluate pubertal development and peripheral concentrations of gonadotrophins and sex hormones in children with shunted hydrocephalus compared with healthy controls. STUDY DESIGN: 114 patients (52 females, 62 males) and 73 healthy controls (35 females, 38 males) aged 5 to 20 years were analysed for stage of puberty, age at menarche, testicular volume, basal serum follicle stimulating hormone (FSH), luteinising hormone (LH), sex hormone binding globulin (SHBG), testosterone and oestradiol concentrations, and free androgen index. RESULTS: Male gonadal and male and female pubic hair development occurred significantly earlier in the patients than in the controls. The mean age at menarche was significantly lower in the female patients than in their controls (11.7 v 13.2 years; p < 0.001), and lower than it had been for their mothers (v 13.1 years; p < 0.001). Relative testicular volume was higher in the male patients than in their controls (1.2 standard deviation score (SDS) v 0.2 SDS; p < 0.001). The prepubertal patients had higher basal LH (0.13 U/l v 0.08 U/l; p < 0.001) and SHBG (132.3 nmol/l v 109.1 nmol/l; p < 0.01) than the controls. Both the prepubertal and pubertal females had significantly higher basal FSH than their controls (1.57 U/l v 1.03 U/l; p < 0.05, and 4.0 U/l v 2.9 U/l; p < 0.01, respectively). CONCLUSIONS: Hydrocephalic children experience accelerated pubertal maturation, reflected in a younger age at menarche in females and an increased testicular volume in males. This may be because of enhanced gonadotrophin secretion, possibly resulting from unphysiological variations in intracranial pressure.     

Cognitive functions in relation to MRI findings 30 years after traumatic brain injury

OBJECTIVE: The aim of the study was to relate cognitive effects of a remote traumatic brain injury (TBI) to MRI findings and severity of injury. METHOD: Sixty-one patients were assessed on average 30 years after a TBI of variable severity. A comprehensive cognitive test battery was used to evaluate memory, executive functions and cognitive overall impairment. Multiple regression analyses were used to examine the relationships between cognitive variables and MRI volumetric findings (the volumes of the hippocampus and the lateral ventricles) and local contusions on MRI. Also, the effect of injury severity on cognitive outcome was evaluated. RESULTS: Reductions in hippocampal volumes and lateral ventricular enlargement were significantly associated with impaired memory functions, memory complaints and executive functions. Of the MRI parameters used, the best predictor for cognitive outcome was the volume of the lateral ventricle. There was only a modest relationship between severity of injury and cognitive performance. CONCLUSIONS: The results show that long-term memory impairments after TBI are associated with MRI volumetric measures. This suggests that the degree of diffuse injury leading to atrophic changes is prognostically more important than the initial severity of TBI.     

Allergic rhinitis and pharmacological management in elite athletes

INTRODUCTION: Only a few studies have examined the occurrence of atopy and clinically apparent allergic disease and their pharmacological management in elite athletes. The aim of the study was to assess the frequency of allergic rhinitis and the use of antiallergic medication within the subgroups of elite athletes as compared with a representative sample of young adults of the same age. METHODS: A cross-sectional survey was carried out in 2002. All the athletes (N = 494) financially supported by the National Olympic Committee comprised the study group. Of them, 446 (90.3%) filled in a structured questionnaire concerning asthma and allergies, the use of medication, characteristics of sport activities, and smoking habits. A representative sample of Finnish young adults (N = 1504) served as controls. RESULTS: The endurance athletes reported physician-diagnosed allergic rhinitis more often (36.1%) than other athletes (23.4%) or control subjects (20.2%). The use of antiallergic medication was reported by 33.3, 15.7, and 15.6% of those, respectively. Among both athletes and controls, females reported the use of antiallergic medication more often than males. Only half of those athletes reporting allergic rhinitis had used antiallergic medication during the past year. After adjusting for age and sex, OR (95% CI) for allergic rhinitis and the use of antiallergic medication were 2.24 (1.48-3.39) and 2.79 (1.82-4.28), respectively, in endurance athletes as compared with the controls. CONCLUSIONS: Endurance athletes have physician-diagnosed allergic rhinitis, and they use antiallergic medication more often than athletes in other events or control subjects. Only half of those athletes reporting allergic rhinitis take antiallergic medication. More attention needs to be paid to the optimal management of allergic rhinitis, especially in highly trained endurance athletes.     

Striatal dopamine D2 receptors in modulation of pain in humans: a review

We review evidence indicating that the striatum and striatal dopamine D2 receptors are involved in the regulation of pain in humans. Painful stimulation produces an increase in regional cerebral blood flow in the human striatum. Pain is a common symptom in patients with nigrostriatal dopaminergic hypofunction. Positron emission tomography findings show that a low dopamine D2 receptor availability in the striatum of healthy subjects (indicating either a low density of dopamine D2 receptors or a high synaptic concentration of dopamine) is associated with a high cold pain threshold and a low capacity to recruit central pain inhibition by conditioning stimulation. Patients with chronic orofacial pain have higher dopamine D2 receptor availability than their age-matched controls. We propose that the striatal dopamine D2 receptor may be an important target for the diagnosis and treatment of chronic pain.     

Life satisfaction and depression in a 15-year follow-up of healthy adults

OBJECTIVE: The aim of this study was to investigate the cross-sectional and longitudinal relationship between life satisfaction and depressive symptoms in healthy adults. METHOD: This is a 15-year prospective cohort study with a nationwide sample of healthy Finnish adults (N = 9679), aged 18-45, who responded to postal questionnaires in 1975, 1981 and 1990 including a 4-item life satisfaction (LS) scale (range 4-20) and, in 1990, the 21-item Beck Depression Inventory (BDI). RESULTS: A strong linear association was found between concurrent LS and BDI scales (r = 0.6). With an LS cut-off point of 11/12, moderate/severe depression (BDI > or = 19) was detected with 87% sensitivity, 88 % specificity and a 94% area under the ROC curve. Longitudinally, a strongly increased risk of moderate/severe depression in 1990 was observed among the dissatisfied (LS 12-20) compared with the satisfied (LS 4-6) in 1975 (OR = 6.7; 95 %CI 4.2-10.9) and in 1981 (OR = 10.4; 6.1-17.6). CONCLUSION: The 4-item LS scale can identify a group of healthy people from the general population with a high risk of having or developing depressive symptoms. Since low life satisfaction also indicates an elevated risk of other adverse health outcomes, the assessment of subjective well-being should be encouraged both in surveys and in clinical practice.