Epidemiological and Psychopharmacological Study About Off-Label Treatment in Child and Adolescent Psychiatric Emergencies: A Tertiary/Single Center Experience.

OBJECTIVE: The study used an epidemiological and pharmacological description of child and adolescent psychiatric emergencies (CAPEs), during which psychotropic medications are frequently administered as off-label therapies. METHODS: We retrospectively describe CAPE in 190 patients (mean age, 14.7 years) referring in the emergency department of a single tertiary center, from June 2016 to June 2018, focusing on off-label administration rate, most of all in emergency setting. RESULTS: An intrinsic fragility was observed in this population, where 28.4% of patients present a history of self-harm, 24.7% a concomitant neurodevelopmental disorder, and 17.3% a history of substance abuse. Psychomotor agitation was the most frequent referral reason, and it represents an unspecified clinical presentation of several conditions, while self-harm showed a stronger association with depressive disorders (55.2%).Globally, 811 medications were administered both as baseline therapy (67.8% of off-label rate) and/or in the emergency setting, where the off-label rate raised to 78.3%. Benzodiazepines had the highest rate of off-label use (98.2% as baseline therapy, 92.9% in acute context). Nevertheless, in 83.5% cases of acute administrations, a singular oral benzodiazepine (mostly lorazepam) guaranteed psychomotor agitation resolution, with a lower rate of adverse effects in contrast with atypical antipsychotics. CONCLUSIONS: Off-label drug use in CAPEs is a recurrent clinical practice. An international agreement about off-label drugs is crucial to obtain standard long-term pharmacoepidemiological, safety, and efficacy data. Pharmacological pediatric trials and international guidelines are also required to regulate pharmacological treatments of CAPEs, most of all in emergency settings.

Evaluation of Residual Kidney Function during Once-Weekly Incremental Hemodialysis.

BACKGROUND: The initial once-weekly administration of incremental hemodialysis to patients with residual kidney function (RKF) has recently attracted considerable interest. METHODS: The aim of our study was to assess the performance of a series of different methods in measuring serum urea nitrogen and serum Cr (sCr) RKF in patients on once-weekly hemodialysis (1WHD). Evaluations were carried out by means of 24-h predialysis urine collection (Kr-24H) or 6-day inter-dialysis collection (Kr-IDI) and estimation of glomerular filtration rate based on (KrSUN + KrsCr)/2 for the purpose of identifying a simple reference calculation to be used in assessing RKF in patients on 1WHD dialysis. Ninety-five urine samples were collected from 12 1WHD patients. A solute solver urea and Cr kinetic modeling program was used to calculate residual urea and Cr clearances. Mann-Whitney U test, Pearson's correlation coefficient (R), and linear determination coefficient (R2) were used for statistical analysis. RESULTS: 1WHD patients displayed a mean KrSUN-IDI of 4.5 ± 1.2 mL/min, while KrSUN-24H corresponded to 4.1 ± 0.9 mL/min, mean KrsCr-IDI to 9.1 ± 4.0 mL/min, and KrsCr 24H to 8.9 ± 4.2 mL/min, with a high regression between IDI and 24-h clearances (for IDI had R2 = 0.9149 and for 24H had R2 = 0.9595). A good correlation was also observed between KrSUN-24H and (KrSUN + KrsCR/2) (R2 = 0.7466, p < 0.01. DISCUSSION: Urine collection over a 24-h predialysis period yielded similar results for both KrSUN and KrsCr compared to collection over a longer interdialytic interval (KrSUN + KrsCr)/2 could be applied to reliably assess RKF in patients on 1WHD. CONCLUSION: The parameters evaluated are suitable for use as a routine daily method indicating the commencement and continued use of the 1WHD Incremental Program.

A 12-month follow-up of primary and secondary root canal treatment in teeth obturated with a hydraulic sealer.

OBJECTIVES: This randomized, controlled, pilot study assessed the outcome of non-surgical primary/secondary root canal treatments either with a novel bioactive sealer and the single-cone technique or with gutta-percha, zinc oxide-eugenol sealer (ZOE), and warm vertical compaction. MATERIALS AND METHODS: Sixty-nine patients were randomly divided into two groups that were treated using the single-cone technique with BioRootTM RCS (Septodont) (BIO group) or warm vertical compaction with gutta-percha and ZOE sealer (PCS group). Two subsamples (BIOAP and PCSAP) comprised the cases with apical periodontitis. Treatment was undertaken by four residents using a standardized instrumentation and disinfection protocol. The periapical index (PAI) was recorded, and clinical and radiographic follow-up performed at 1, 3, 6, and 12 months. Treatment success was assessed according to "periapical healing" and "tooth survival". The test for the equality of proportions, t tests for the equality of means, and non-parametric K-sample tests for the equality of medians were applied when appropriate. RESULTS: The survival rate was similar in the BIO and PCS (p = 0.4074) and the BIOAP and PCSAP groups (p = 0.9114). The success rate was higher in the BIO groups, but not statistically significant (p = 0.0735). In both BIOAP and PCSAP groups, a progressive decrease in the PAI was observed. CONCLUSION: At 12 months, both techniques showed reliable results. Further studies and longer follow-ups are needed. CLINICAL RELEVANCE: This study documents the feasibility of using a bioactive sealer in conjunction with the single-cone technique to obturate the root canal and obtaining a predictable outcome. TRIAL REGISTRATION: ClinicalTrials.gov Identifie: NCT04249206.

Cooperative parent-mediated therapy for Italian preschool children with autism spectrum disorder: a randomized controlled trial.

Parent-mediated intervention is widely used for pre-schoolers with autism spectrum disorder (ASD). Previous studies indicate small-to-moderate effects on social communication skills, but with a wide heterogeneity that requires further research. In this randomized controlled trial (RCT), cooperative parent-mediated therapy (CPMT) an individual parent coaching program for young children with ASD was administered to preschool children with ASD. All children received the same low-intensity psychosocial intervention (LPI) delivered in community settings, to evaluate the potential additional benefit of CPMT. Thirty-four participants with ASD (7 females; 27 males; aged 2, 6, 11 years) and their parents were included in the trial. The primary blinded outcome was social communication skills, assessed using the ADOS-G social communication algorithm score (ADOS-G SC). Secondary outcomes included ASD symptom severity, parent-rated language abilities and emotional/behavioral problems, and self-reported caregiver stress. Evaluations were made at baseline and post-treatment (at 6 months) by an independent multidisciplinary team. Results documented that CPMT showed an additional benefit on LPI with significant improvements of the primary blinded outcome, socio-communication skills, and of some secondary outcomes such as ASD symptom severity, emotional problems and parental stress related to parent-child dysfunctional interaction. No additional benefit was found for language abilities. Findings of our RCT show that CPMT provide an additional significant short-term treatment benefit on ASD core symptoms, when compared with active control group receiving only LPI.

Tyrosinase and nestin immunohistochemical expression in melanocytic nevi as a histopathologic pattern to trace melanocyte differentiation and nevogenesis.

While histological analysis represents a powerful tool for the classification of melanocytic lesions as benign or malignant, a clear-cut distinction between a nevus and a melanoma is sometimes a challenging step of the diagnostic process. The immunohistochemical detection of tyrosinase, cardinal melanogenic enzyme during melanocytic maturation, has often been helpful in formulating a differential diagnosis due to the peculiar staining pattern in nevocytes compared with melanoma cells. Tyrosinase distribution in nevi appears to overlap with the cytoarchitectural changes observable within these lesions, that result in epidermal or superficial dermal nevocytes being larger and strongly expressing melanocytic differentiation antigens, such as tyrosinase, compared with deeper dermal nevus cells. Our study aimed to evaluate the immunohistochemical expression pattern of tyrosinase in different histological types of acquired dysplastic melanocytic nevi, including junctional, compound, and intradermal nevi. Moreover, to estimate whether in nevocytes the expression of tyrosinase was associated with their differentiation state, we investigated the expression of two recognized markers of pluripotency, CD34 and nestin. In all examined nevi, our analysis revealed a remarkable immunoreactivity for tyrosinase in junctional and superficial dermal nevocytes and a decreasing gradient of staining in dermal nevocytes, up to become negative in deeper dermis. Meanwhile, junctional and dermal nevocytes were lacking in CD34 protein. Furthermore, nestin immunostaining showed an opposite distribution compared with tyrosinase, leading us to look into the tyrosinase/nestin expression pattern in melanocytic nevus as a tool to better understand the final stages of differentiation of melanocyte precursors toward their ultimate anatomical site into the epidermis.

Population-based analysis of hospitalizations for patients with systemic sclerosis in a West-European region over the period 2001-2012.

The aim of this study was to evaluate systemic sclerosis (SSc) hospitalizations through a retrospective population-based study analyzing administrative data during 2001-2012 in Sardinia, an Italian region with universal Health System coverage. Data on hospital discharge records with ICD-9-CM code for SSc (710.1) were obtained from the Department of Health and Hygiene. Two-tailed Cochran-Armitage test for trend was applied to analyze the annual trend for primary and non-primary discharge diagnoses. SSc prevalence was also estimated. This study included 4981 hospitalizations in 736 patients (84.8 % women). Hospitalizations with SSc as primary diagnosis were 3631 (72.9 %). Their annual number significantly increased during study period, from 143 in 2001 to 390 in 2012. Annual trend analysis revealed statistically significant increase in number and percentage of interstitial lung disease (p < 0.0001), pulmonary arterial hypertension (p < 0.0024), osteoporotic fragility fractures (p < 0.0001), ulcers, and gangrene (p = 0.0037) as non-primary diagnoses associated with SSc. Although the number of admissions with SSc as non-primary diagnosis showed a slight reduction during the study period, the annual number and percentage of admissions with respiratory failure (p = 0.0016) and congestive heart failure (p < 0.0001) as primary diagnosis showed a significant upward trend. Admissions for intravenous infusion, mainly day-hospital, accounted for 19.1 % of all hospitalizations for SSc and showed a significant (p = 0.0002) upward trend in 2001-2012. The 2012 SSc prevalence in Sardinia was estimated to be 34.8 per 100,000 inhabitants. Hospital care utilization for SSc is changing over time, showing increased hospitalizations aimed at the early recognition and treatment for the major manifestations and complications of SSc.

Association between child behavioural problems and parenting stress in autism spectrum disorders: the role of parenting self-efficacy.

Introduction: The present study build on previous research that found a bidirectional relation of parenting stress and negative behavioural outcomes in children with Autism Spectrum Disorders. Aim: To investigate the mediating role of parenting self-efficacy in the relationship of parenting stress and children's behavioural and emotional problems. Materials and methods: The sample included 32 young children and their families. Sociodemographic and clinical data were collected. Hierarchical regression analysis revealed direct and indirect mediating effects. Results: Parenting self-efficacy mediated the relationship between parenting stress and children's behavioural and emotional problems in fathers only. Conclusions: We discuss potential ways targeted parenting self-efficacy intervention can support fathers. Results contribute to gain father-informed knowledge in, a research branch generally focused on mothers.

What Factors Predict Adaptive Functioning in Preschool Children with Autism Spectrum Disorder? A Longitudinal Study.

Adaptive functioning constitutes a fundamental aspect of the phenotype associated with autism spectrum disorder (ASD) in preschool-aged children, exerting a significant influence on both the child and the family's overall quality of life. The aim of this study was to investigate the predictors of the adaptive functioning domains in preschool-age children with ASD at two time points, providing a snapshot of this fundamental developmental step. Methods: Ninety-five children with ASD (M = 3.89, SD = 1.13) were included in the study and longitudinal data (the mean length of the longitudinal data collection was 1 year) on ASD features such as social communication and social interaction, repetitive and restricted behavior, cognitive level, and adaptive functioning were collected. We considered autistic features, cognitive level, and sociodemographic factors as possible predictors of the different adaptive functioning domains one year later. Results: Data obtained showed a worsening of the ASD features and adaptive functioning after one year. Furthermore, the severity of repetitive and restricted behavior predicted adaptive functioning, especially in the social and practical domains of the child, one year later. This prediction was observed alongside the child's cognitive level. Conclusions: The study identifies some potential predictive factors of specific adaptive functioning domains in preschoolers with ASD. Considering how critical adaptive functioning is for the well-being of both the child and their family, it becomes imperative to design early-stage interventions focused on nurturing adaptive skills in children with ASD.

Autism Spectrum Disorder and Early Psychosis: a narrative review from a neurodevelopmental perspective.

Autism Spectrum Disorder (ASD), characterized by socio-communicative abnormalities and restricted, repetitive, and stereotyped behaviors, is part of Neurodevelopmental Disorders (NDDs), a diagnostic category distinctly in accordance with the Diagnostic and Statistical Manual of Mental Disorders, 5th Edition, (DSM-5), clearly separated from Schizophrenia Spectrum Disorder (SSD) (schizophrenia, schizophreniform disorder, schizoaffective disorder, schizotypal personality disorder). Over the last four decades, this clear distinction is gradually being replaced, describing ASD and SSD as two heterogeneous conditions but with neurodevelopmental origins and overlaps. Referring to the proposal of a neurodevelopmental continuum model, the current research's aim is to provide an update of the knowledge to date on the course of clinical symptoms and their overlaps among ASD and SSD. A narrative review of the literature published between January 2010 and June 2023 was conducted. Five studies were included. All studies show a global impairment in both conditions. Two studies show a focus on neurodevelopmental perspective in ASD and SSD. Only one study of these adopts a longitudinal prospective in terms of prognostic markers among ASD and SSD. Three studies underline the overlap between ASD and SSD in terms of negative, disorganized and positive symptomatology. To date, there is a gap in the current scientific literature focused on ASD-SSD course of clinical symptoms and their overlaps from a neurodevelopmental perspective. Future longitudinal studies to identify risk markers and tailored treatments are needed.

Early and stable difficulties of everyday executive functions predict autism symptoms and emotional/behavioral problems in preschool age children with autism: a 2-year longitudinal study.

Introduction: Longitudinal studies of autistic children show that autism symptoms and emotional/behavioral problems vary and change over time. However, the factors that affect this variability remain far from certain and very little is known about what take place in the preschool period and the role of executive functions (EF). Methods: Here, we test the influence of stable difficulties in everyday executive functioning (EEF) during early childhood across 2 years on autistic symptoms and emotional and behavioral problems. Twenty-nine autistic children (24 males and 5 females) were assessed twice within the space of 2 years. At baseline (M = 29 months, SD =5.6 months), participants were assessed for EEF, cognitive development, autistic symptoms, and emotional/behavioral problems. At follow-up, we repeated the same assessment except for cognitive development. Results: The group with stable difficulties (across 2 years) in EEF during early childhood showed a worsening in the severity of autistic symptoms and emotional and behavioral problems compared with children without EEF difficulties (p < 0.05), and these effects cannot be attributable to cognitive development. Discussion: Our results suggest that early and stable EEF plays the role of a modifier by interacting with the core domains of autism, in particular with the social affect domain (SA CSS), influencing social cognition and exacerbating or lessening symptom expression and emotional behavioral problems. These short-term longitudinal and preliminary findings underscore the importance of EEF as necessary target for early intervention in children with autism.

Psychiatric Comorbidities in Children and Adolescents with High-Functioning Autism Spectrum Disorder: A Study on Prevalence, Distribution and Clinical Features in an Italian Sample.

This study investigated the prevalence and distribution of psychiatric comorbidities in a group of 472 children and adolescents with ASD aged 3-18 years. We examined differences in age, sex, IQ, adaptive skills, and ASD symptom severity by comparing participants with ASD (ASD group) with participants with ASD and a psychiatric disorder (ASD/PSY group). Overall, 32.2% of participants had a comorbid psychiatric condition. Attention deficit/hyperactivity disorder (ADHD) was the most frequent diagnosis among preschoolers (20.4%); among school-age children, ADHD and anxiety/obsessive-compulsive disorders were the most frequent conditions (21% and 10.6%, respectively); finally, adolescents exhibit higher prevalence of anxiety/obsessive-compulsive disorders (21.8%). The ASD/PSY group showed a higher percentage of males, they were older and showed lower adaptive skills than the group with ASD; moreover, their mothers exhibited higher stress levels than mothers of participants in the ASD group. The comparison between age groups in participants within ASD/PSY group revealed that preschoolers had lower IQ than school-age children and adolescents, and worse adaptive skills, more repetitive behaviors, and restricted interests than adolescents. This study highlights the importance of an accurate diagnosis of psychiatric comorbidities in children and adolescents with ASD, also considering individual and family impairment.

Autism spectrum disorder, very-early onset schizophrenia, and child disintegrative disorder: the challenge of diagnosis. A case-report study.

Background: Autism spectrum disorder (ASD) in the Diagnostic and Statistical Manual of Mental Disorders Fifth Edition (DSM-5) contains several disorders previously present as distinct diagnoses in the DSM Revised Fourth Edition (DSM-IV-TR). These include child disintegrative disorder (CDD). The latter presents typical features, such as a late regression of developmental acquisitions. However, it also shows symptoms similar to ASD, and psychotic symptoms, such as very-early onset schizophrenia (VEOS), are described in the literature. Case report: In this case report we deepen the case of P., a child who presents a late regression, at 7 years old, associated with psychotic symptoms in the absence of organic alterations. The child was treated with antipsychotic drug therapy and cognitive behavioral therapy. P. was diagnosed with ASD with acute and late regression associated with psychotic symptoms. During the follow-up, there was a gradual improvement in the clinical conditions. Improvements were possible due to therapeutic intervention (pharmacological and psychotherapeutic) and/or the natural course of the disorder. Conclusion: The diagnostic difficulty of this case reflects a clinical complexity in which it is not easy to distinguish between neurodevelopmental and psychiatric aspects. Clinical cases such as that of P. emphasize the theme of the neurodevelopment continuum model in which neurodevelopmental and psychiatric disturbances can be considered within a pattern of pathological continuity.

Recurrent nasal basal cell carcinoma treated with standard surgery excision: evaluation of volume ratio.

BACKGROUND: Basal cell carcinoma (BCC) is the most common malignant skin tumor. Although it rarely evolves into a metastatic disease, BCC can lead to a significant morbidity due to local invasion. The risk of lesion recurrence depends on clinical and histopathological factors as described by the Nation Comprehensive Cancer Network (NCCN). The surgical excision margins have a well-known role: there is a close relationship between high recurrence rate of BCC and the tumor proximity to the surgical margins. Aim of our study was to assess whether there is a significative correlation between recurring BCC and volume ratio (VRb/t), defined as ratio between excisional biopsy volume and tumor volume, and if VRb/t is a useful parameter to assess the risk of recurrence of BCC. METHODS: Retrospective case-control study in 80 patients with history of recurrent basal cell carcinoma of the nose (cases), and 43 patients with history of basal cell carcinoma of the nose with no evidence of relapse (controls) in the following 8 years. RESULTS: Surgical excision margins, histological subtype, ulceration, depth of invasion and volume ratio (VRb/t) were evaluated in case and controls. The evaluation of VRb/t evidenced a significant difference between recurrent BCC and non-recurrent BCC. The mean values of VRb/t were 6.17 for cases and 11.94 for controls. The Binomial Logistic Regression has displayed, for values of VRb/t around 7, a probability of 75% to identify BCCs belonging to the recurrent group. CONCLUSIONS: Our data show a significant correlation between recurrent BCCs and VRb/t. VRb/t can help in the assessment of recurrence risk, used together with others prognostic factor. For values of VRb/t close to 7 it should be recommended a close follow-up to promptly identify a possible recurrence.

The teleNIDA: Early Screening of Autism Spectrum Disorder Through a Novel Telehealth Approach.

The COVID-19 pandemic has fast-tracked interest in telehealth methods to guarantee the continuity of care of children with Autism Spectrum Disorder (ASD). Store-and-forward telehealth approaches offer the opportunity to facilitate timely screening of ASD, allowing parents to record videos of their child's behaviors, subsequently shared with clinicians that provide an assessment remotely. This study aimed to examine the psychometric properties of a new telehealth screening tool, the teleNIDA, administered in home settings for remote observation of early signs of ASD in toddlers aged 18-30 months. Results showed good psychometric properties of the teleNIDA, as compared to the gold standard in-person assessment, and the predictive validity on the diagnosis of ASD at 36 months was demonstrated. This study supports the teleNIDA as a promising level 2 screening tool for ASD able to speed up diagnostic and intervention processes.

Risk and protective factors of quality of life for children with autism spectrum disorder and their families during the COVID-19 lockdown. An Italian study.

BACKGROUND: The lockdown due to the COVID-19 pandemic has been a difficult period for children with Autism Spectrum Disorder (ASD), and their families. AIMS: The aim of this study was to investigate the predictors of the quality of life (QoL) of children with ASD and their parents throughout the first lockdown, providing a snapshot of the impact of the pandemic on these families life. METHOD AND PROCEDURES: A cohort of 243 parents of children with ASD (2-15 years old) completed an original online survey regarding the modification of ASD cores symptoms during lockdown, the type of interventions they had done before and during lockdown and the activities performed by the child. Respondents filled the PedsQL for themselves and their children. OUTCOME AND RESULTS: The data obtained show a worsening of specific ASD core symptoms during lockdown and their role in predicting parents and children's QoL. Furthermore, protective factors for a better children's QoL as the Telehealth intervention, and some activities done at home during the lockdown as physical activity and play with parents are identified. CONCLUSIONS: This study identifies the QoL's risk and protective factors for children with ASD and their families. Furthermore, reveals the fundamental role of the parents as children's QoL protective factor, suggesting a higher collaboration between families and health care providers, whilst potentially improving families and children's QoL.

Sex Differences in Autism Spectrum Disorder: Diagnostic, Neurobiological, and Behavioral Features.

Autism Spectrum Disorder (ASD) is a complex neurodevelopmental disorder with a worldwide prevalence of about 1%, characterized by impairments in social interaction, communication, repetitive patterns of behaviors, and can be associated with hyper- or hypo-reactivity of sensory stimulation and cognitive disability. ASD comorbid features include internalizing and externalizing symptoms such as anxiety, depression, hyperactivity, and attention problems. The precise etiology of ASD is still unknown and it is undoubted that the disorder is linked to some extent to both genetic and environmental factors. It is also well-documented and known that one of the most striking and consistent finding in ASD is the higher prevalence in males compared to females, with around 70% of ASD cases described being males. The present review looked into the most significant studies that attempted to investigate differences in ASD males and females thus trying to shade some light on the peculiar characteristics of this prevalence in terms of diagnosis, imaging, major autistic-like behavior and sex-dependent uniqueness. The study also discussed sex differences found in animal models of ASD, to provide a possible explanation of the neurological mechanisms underpinning the different presentation of autistic symptoms in males and females.

Epidemiology of osteoporosis in an isolated Sardinian population by using quantitative ultrasound.

This study aimed at estimating the prevalence of osteoporosis and osteopenia in a Sardinian isolated population using hand quantitative ultrasound and at investigating the associated factors. The authors utilized a subset of data from a large population-based epidemiologic survey carried out in the Ogliastra region of Sardinia between 2003 and 2008. The sample consists of 6,326 men and women aged ≥30 years, who underwent quantitative ultrasound at the phalanges, bioelectrical impedance, anthropometric measurements, blood tests, and a standardized epidemiologic questionnaire collecting sociodemographic, lifestyle, medical, physiologic, and pharmacologic data. The T-score thresholds for amplitude-dependent speed of sound of -3.2 standard deviations and between -3.2 and -1 standard deviations were used to diagnose osteoporosis and osteopenia, respectively. Prevalence of osteoporosis was 17.0% in women and 5.2% in men. Logistic regression analysis revealed that factors associated with osteoporosis were age, anthropometric and bioimpedance measures, alkaline phosphatase levels, and menopause in women. High education, exercise, and beer consumption seem to be protective factors, whereas a family history of osteoporosis is a risk factor. Results show that osteoporosis in this population is comparable with that found in different countries, suggesting that quantitative ultrasound could be used more widely to detect high-risk individuals for preventing osteoporotic fractures.

Analysis of 12,517 inhabitants of a Sardinian geographic isolate reveals that predispositions to thrombocytopenia and thrombocytosis are inherited traits.

BACKGROUND: Thrombocytopenia is a common finding in several diseases but almost nothing is known about the prevalence of thrombocytopenia in the general population. We examined the prevalence of thrombocytopenia and determinants of platelet count in a healthy population with a wide age range. DESIGN AND METHODS: We performed a cross-sectional study on 12,517 inhabitants of ten villages (80% of residents) in a secluded area of Sardinia (Ogliastra). Participants underwent a complete blood count evaluation and a structured questionnaire, used to collect epidemiological data. RESULTS: We observed a platelet count lower than 150 × 109/L in 3.2% (2.8%-3.6%) of females and 4.8% (4.3%-5.4%) of males, with a value of 3.9% (3.6%-4.3%) in the entire population. Thrombocytopenia was mild (platelet count: 100 × 109/L-150 × 109/L), asymptomatic and not associated with other cytopenias or overt disorders in most cases. Its standardized prevalence was quite different in different villages, with values ranging from 1.5% to 6.8%, and was negatively correlated with the prevalence of a mild form of thrombocytosis, which ranged from 0.9% to 4.5%. Analysis of platelet counts across classes of age revealed that platelet number decreased progressively with aging. As a consequence, thrombocytopenia was nearly absent in young people and its prevalence increased regularly during lifetime. The opposite occurred for thrombocytosis. CONCLUSIONS: Given the high genetic differentiation among Ogliastra villages with "high" and "low" platelet counts and the substantial heritability of this quantitative trait (54%), we concluded that the propensity to present mild and transient thrombocytosis in youth and to acquire mild thrombocytopenia during aging are new genetic traits.

A strategy analysis for genetic association studies with known inbreeding.

BACKGROUND: Association studies consist in identifying the genetic variants which are related to a specific disease through the use of statistical multiple hypothesis testing or segregation analysis in pedigrees. This type of studies has been very successful in the case of Mendelian monogenic disorders while it has been less successful in identifying genetic variants related to complex diseases where the insurgence depends on the interactions between different genes and the environment. The current technology allows to genotype more than a million of markers and this number has been rapidly increasing in the last years with the imputation based on templates sets and whole genome sequencing. This type of data introduces a great amount of noise in the statistical analysis and usually requires a great number of samples. Current methods seldom take into account gene-gene and gene-environment interactions which are fundamental especially in complex diseases. In this paper we propose to use a non-parametric additive model to detect the genetic variants related to diseases which accounts for interactions of unknown order. Although this is not new to the current literature, we show that in an isolated population, where the most related subjects share also most of their genetic code, the use of additive models may be improved if the available genealogical tree is taken into account. Specifically, we form a sample of cases and controls with the highest inbreeding by means of the Hungarian method, and estimate the set of genes/environmental variables, associated with the disease, by means of Random Forest. RESULTS: We have evidence, from statistical theory, simulations and two applications, that we build a suitable procedure to eliminate stratification between cases and controls and that it also has enough precision in identifying genetic variants responsible for a disease. This procedure has been successfully used for the beta-thalassemia, which is a well known Mendelian disease, and also to the common asthma where we have identified candidate genes that underlie to the susceptibility of the asthma. Some of such candidate genes have been also found related to common asthma in the current literature. CONCLUSIONS: The data analysis approach, based on selecting the most related cases and controls along with the Random Forest model, is a powerful tool for detecting genetic variants associated to a disease in isolated populations. Moreover, this method provides also a prediction model that has accuracy in estimating the unknown disease status and that can be generally used to build kit tests for a wide class of Mendelian diseases.