Biomedical subjects

Walter H Kaye

Publications and source records attributed to Walter H Kaye.

43 records · Page 3Linked to original sources

PubMed2003

A review of neuropeptide and neuroendocrine dysregulation in anorexia and bulimia nervosa.

Neuropeptides play an important role in the regulation of feeding behavior and obesity. The mechanisms for controlling food intake involve a complicated interplay between peripheral systems (including gustatory stimulation, gastrointestinal peptide secretion, and vagal afferent nerve responses) and central nervous system (CNS) neuropeptides and/or monoamines. These neuronal systems include neuropeptides (CRH, opioids, neuropeptide-Y (NPY) and peptide YY (PYY), vasopressin and oxytocin, CCK, and leptin) and monamines (serotonin, dopamine, norepinephrine). In addition to regulating eating behavior, a number of CNS neuropeptides participate in the regulation of neuroendocrine pathways. Thus, clinical studies have evaluated the possibility that CNS neuropeptide alterations may contribute to dysregulated secretion of the gonadal hormones, cortisol, thyroid hormones and growth hormone in the eating disorders. Most of the neuroendocrine and neuropeptide alterations apparent during symptomatic episodes of AN and BN tend to normalize after recovery. This observation suggests that most of the disturbances are consequences rather than causes of malnutrition, weight loss and/or altered meal patterns. Still, an understanding of these neuropeptide disturbances may shed light on why many people with AN or BN cannot easily "reverse" their illness and even after weight gain and normalized eating patterns, many individuals who have recovered from AN or BN have physiological, behavioral and psychological symptoms that persist for extended periods of time.

Animals↗

PubMed2003

Neurotransmitter and imaging studies in anorexia nervosa: new targets for treatment.

Anorexia and Bulimia Nervosa are disorders of unknown etiology that invariably begin during adolescence and near in time to puberty in young women. These disorders are associated with aberrant eating behaviors, body image distortions, impulse and mood disturbances, as well as characteristic temperament and personality traits. It is well known that malnutrition produces changes in neuroendocrine function. More recently, disturbances in neuronal systems have been found to play a role in the modulation of feeding, mood, and impulse control. These neuronal systems include neuropeptides (CRH, opioids, neuropeptide-Y (NPY) and peptide YY (PYY), vasopressin and oxytocin, CCK, and leptin) and monoamines (serotonin, dopamine, norepinephrine). Disturbances of most of these neuronal systems have been found when people are ill with an eating disorder, but it was not certain whether they were a cause or consequence of symptoms. In order to address these questions, a growing number of studies have investigated whether neuromodulatory disturbances persist after recovery. Studies from several centers tend to show altered serotonin activity persists after prolonged normalization of weight, nutrition, and menstrual function, as do anxiety, obsessionality, and perfectionism. While there are fewer data, there may be persistent alterations of dopamine or some neuropeptides in some subjects in a recovered state. The inaccessibility of the central nervous system has made it difficult to understand brain and behavior. In the past decade, new tools, such as brain imaging, have offered the possibility of better characterization of complex neuronal function and behavior. Such studies have tended to consistently find that alterations of brain regions, such as the temporal lobe, occur in people who are ill with anorexia nervosa and appear to persist after some degree of weight gain and recovery. New imaging technology, that marries Positron Emission Tomography (PET) imaging with selective neurotransmitter radioligands, confirms that altered serotonin neuronal pathway activity persists after recovery from an eating disorder and supports the possibility that these psychobiological alterations might contribute to traits, such as increased anxiety or extremes of impulse control, that, in turn, may contribute to a vulnerability to the development of an eating disorder. In summary, studies of pathophysiology are starting to nominate new candidates for treatment leading to the possibility of finding effective treatments for this often chronic or fatal disorder.

Animals↗

PubMed2002

Significant linkage on chromosome 10p in families with bulimia nervosa.

Bulimia nervosa (BN) is strongly familial, and additive genetic effects appear to contribute substantially to the observed familiality. In turn, behavioral components of BN, such as self-induced vomiting, are reliably measured and heritable. To identify regions of the genome harboring genetic variants conferring susceptibility to BN, we conducted a linkage analysis of multiplex families with eating disorders that were identified through a proband with BN. Linkage analysis of the entire sample of 308 families yielded a double peak, with the highest nonparametric multipoint maximum LOD score (MLS), of 2.92, on chromosome 10. Given the high heritability of self-induced vomiting and the reliability with which it can be measured, we performed linkage analysis in a subset (n=133) of families in which at least two affected relatives reported a symptom pattern that included self-induced vomiting. The highest MLS (3.39) observed was on chromosome 10, between markers D10S1430 and D10S1423. These results provide evidence of the presence of a susceptibility locus for BN on chromosome 10p. Using simulations, we demonstrate that both of these scores, 2.92 and 3.39, meet the widely accepted criterion for genomewide significance. Another region on 14q meets the criterion for genomewide suggestive linkage, with MLSs of 1.97 (full sample) and 1.75 (subset) at 62 centimorgans from p-ter.

Bulimia↗

PubMed2002

Reduced 5-HT2A receptor binding after recovery from anorexia nervosa.

BACKGROUND: Several lines of evidence suggest that a disturbance of serotonin neuronal pathways may contribute to the pathogenesis of anorexia nervosa (AN). This study applied positron emission tomography (PET) to investigate the brain serotonin 2A (5HT2A) receptor, which could contribute to disturbances of appetite and behavior in AN. METHODS: To avoid the confounding effects of malnutrition, we studied 16 women recovered from AN (REC AN, >1 year normal weight, regular menstrual cycles, no bingeing or purging) compared with 23 healthy control women (CW) using [18F]altanserin, a specific 5-HT2A receptor antagonist on PET imaging. RESULTS: REC AN women had significantly reduced [18F]altanserin binding relative to CW in mesial temporal (amygdala and hippocampus), as well as cingulate cortical regions. In a subset of subjects (11 CW and 16 REC AN), statistical parametric mapping (SPM) confirmed reduced mesial temporal cortex 5HT2A receptor binding and, in addition, showed reduced occipital and parietal cortex binding. CONCLUSIONS: This study extends research suggesting that altered 5-HT neuronal system activity persists after recovery from AN and may be related to disturbances of mesial temporal lobe function. Altered 5-HT neurotransmission after recovery also supports the possibility that this may be a trait-related disturbance that contributes to the pathophysiology of AN.

Adult↗

PubMed2002

Linkage analysis of anorexia nervosa incorporating behavioral covariates.

Eating disorders, such as anorexia nervosa (AN) and bulimia nervosa (BN), have genetic and environmental underpinnings. To explore genetic contributions to AN, we measured psychiatric, personality and temperament phenotypes of individuals diagnosed with eating disorders from 196 multiplex families, all accessed through an AN proband, as well as genotyping a battery of 387 short tandem repeat (STR) markers distributed across the genome. On these data we performed a multipoint affected sibling pair (ASP) linkage analysis using a novel method that incorporates covariates. By exploring seven attributes thought to typify individuals with eating disorders, we identified two variables, drive-for-thinness and obsessionality, which delimit populations among the ASPs. For both of these traits, or covariates, there were a cluster of ASPs who have high and concordant values for these traits, in keeping with our expectations for individuals with AN, and other clusters of ASPs who did not meet those expectations. When we incorporated these covariates into the ASP linkage analysis, both jointly and separately, we found several regions of suggestive linkage: one close to genome-wide significance on chromosome 1 (at 210 cM, D1S1660; LOD = 3.46, P = 0.00003), another on chromosome 2 (at 114 cM, D2S1790; LOD = 2.22, P = 0.00070) and a third region on chromosome 13 (at 26 cM, D13S894; LOD = 2.50, P = 0.00035). By comparing our results to those implemented using more standard linkage methods, we find the covariates convey substantial information for the linkage analysis.

Anorexia Nervosa↗

PubMed2002

Personality, perfectionism, and attitudes toward eating in parents of individuals with eating disorders.

OBJECTIVE: This study compares personality and eating-related traits in parents of probands with eating disorders, with age-band matched healthy normal controls. METHOD: Data were abstracted from an international genetic study of anorexia nervosa. Information was available for the Multidimensional Perfectionism Scale (MPS), the Eating Disorders Inventory (EDI), and the Temperament and Character Inventory (TCI). Comparisons were done by multivariate analysis of variance. RESULTS: Mothers of probands showed elevated levels of perfectionism on the MPS and more concerns about weight and shape on the EDI compared with controls. Mothers who had daughters with diagnoses other than the restricting subtype of anorexia nervosa showed elevated levels of perfectionism on the MPS. CONCLUSION: These data are compatible with the notion that some personality traits, such as perfectionism, and weight and shape concerns may cluster in families of probands with eating disorders.

Analysis of Variance↗

PubMedDate not supplied

Features associated with laxative abuse in individuals with eating disorders.

OBJECTIVE: Laxative abuse is common in patients with anorexia and bulimia nervosa and has been associated with longer duration of illness, suicide attempts, impulsivity, and greater eating and general psychopathology. We explored the extent to which laxative abuse was associated with specific psychopathological features across eating disorder subtypes. METHODS: Participants were 1021 individuals from the multisite, International Price Foundation Genetic Studies. Axis I disorders, personality disorders and traits, and obsessive compulsive features were assessed. RESULTS: Laxative abuse was associated with worse eating disorder and general psychopathology and higher prevalence of borderline personality disorder (BPD). Symptom level analyses revealed that specific features of BPD, including suicidality and self-harm, feelings of emptiness, and anger, were most strongly associated with laxative abuse. CONCLUSIONS: The function of laxative abuse may differ across individuals with eating disorders, alternatively serving as a method of purging and a form of self-harm.

Anger↗