Arianna Parodi

Relationship between body mass index and asthma characteristics in a group of Italian children and adolescents

The prevalence of asthma and obesity, two often associated conditions, is influenced not only by age and gender but also by lifestyle factors. This study aimed to determine whether, in a Mediterranean northern Italian region, Liguria, an increased prevalence of obesity could be detected in asthmatic children and adolescents and to evaluate the possible relationship between body mass index (BMI) and the characteristics and/or severity of asthma. BMI was determined in 554 asthmatic subjects (2.2-16.1 years) and 625 age-matched controls; BMI was expressed as a continuous variable in standard deviation score (SDS) units, determined as difference between the individual observed value and the reference mean for age and sex, divided by the corresponding standard deviation (BMI-SDS). Overweight/obesity was set at BMI-SDS of 2 or more. BMI-SDS was significantly higher in controls than in asthmatics (p = 0.04); however, the proportion of overweight/obesity subjects (BMI-SDS > or = 2) was similar in controls and in asthmatic patients (p = 0.08). Evaluation of the asthmatic group revealed that BMI-SDS was independent of gender (p = 0.57), atopic sensitization (p = 0.69), and comorbidity with other allergic symptoms (p = 0.60). By contrast, BMI-SDS was lower in preschool-age children than in school-age children and adolescents (p < 0.0001), in subjects with a high rate of acute respiratory tract infections (p = 0.04), and in those not treated with inhaled corticosteroids (IGCs) (p = 0.02). Although an increase in the prevalence of overweight/obesity was not detected in asthmatic children and adolescents, the results reported here suggest a preventive surveillance of calorie intake and a promotion of physical activity in children requiring long-term treatment with inhaled glucocorticosteroids.

Evaluation of insulin resistance in a cohort of HIV-infected youth

OBJECTIVE Metabolic abnormalities, including impairment of glucose homeostasis, have been well characterized in HIV-infected patients. In contrast to adults, insulin resistance and diabetes mellitus appear to be relatively uncommon finding in youth. DESIGN We assessed insulin resistance, and associated risk factors, in a population of vertically HIV-infected children and young adults, when compared with a control population of healthy children. METHODS At the time of enrolment, weeks of pregnancy, birth weight, sex, age, weight, height, body mass index (BMI), pubertal stages, CDC classification, blood pressure, clinical lipodystrophy, hepatitis B or C co-infection, antiretroviral therapy, CD4 T lymphocyte counts, and HIV-RNA levels were recorded. Fasting plasma glucose and insulin levels and homeostatic model assessment-insulin resistance (HOMA-IR) were determined. These parameters were compared between HIV patients and healthy controls with multivariate analyses. RESULTS Fasting insulin levels (OR=1.21, P<0.001) and glycemia (OR=0.89, P<0.001) were significantly different between HIV-infected patients and controls. Antiretroviral therapy duration (r=0.281, P<0.05), triglyceride levels (r=0.286, P<0.05), age (r=0.299, P<0.05), and BMI SDS (r=0.485, P<0.001) were significant predictor variables of insulin resistance, expressed as HOMA-IR. Moreover, clinical lipodystrophy seems to be strongly correlated to glycemia (P<0.05), triglyceride levels (P<0.05), serum insulin levels (P<0.001), HOMA-IR (P<0.05), and also with therapy duration (P<0.05). CONCLUSIONS Both HIV infection and antiretroviral therapy demonstrate differential effects on glucose metabolism in HIV-infected children. Targeted prevention of insulin resistance and diabetes mellitus in HIV-infected children and young adults is needed in order to avoid the associated long-term complications that would otherwise occur, given the improvement in life expectancy of HIV-infected individuals.

Bone quality assessed by phalangeal quantitative ultrasonography in children and adolescents with isolated idiopathic growth hormone deficiency

Objective: Some observations indicate that GH deficiency (GHD) may have little impact on bone mineralization in contrast to its effects on bone growth and maturation. The aim of the present study was to evaluate the effects of isolated GHD and GH-replacement therapy on bone quality assessed by a quantitative ultrasound (QUS) technique at the proximal phalanges of the hand. Design: Growth and QUS data of 68 subjects (50 males and 18 females) aged 5–18 yr with isolated GHD were retrospectively examined. A cross-sectional series of 120 observations was collected and compared with data obtained from a control population (1227 healthy children, 641 males and 586 females, aged 3–16 yr). Methods: QUS variables amplitude-dependent speed of sound (AD-SoS) and bone transmission time (BTT) were assessed by the sonographic device DBM Sonic BP IGEA. Height and weight measurements were performed according to standard techniques. In patients, skeletal age (SA) was determined by Tanner-Whitehouse method (3rd version). Results: Before treatment height, SA, AD-SoS and BTT were reduced in patients. Height SD score (SDS), SA SDS, AD-SoS SDS, and BTT SDS improved during treatment. Significant associations of both AD-SoS and BTT with age, SA, height, and therapy duration were observed. Using multivariate regression models the disease state, SA, and height proved to be significant variables in predicting BTT and AD-SoS. Conclusions: QUS measurements adjusted for body size and skeletal maturity in GHD patients seem to be only slightly reduced. A body size and skeletal maturity adjustment should be incorporated in studies on bone mass in GHD children and adolescents. A non-invasive technique such as QUS technology opens new perspectives.

Skeletal Age as a Determinant of Phalangeal Quantitative Ultrasound Measures of Bone Quality in Children and Adolescents

Background: Quantitative ultrasonography of the proximal phalanges of the hand (QUS) has emerged as an attractive technical choice to assess bone quality features both in terms of bone mass and structure. Strong associations were found between QUS measures, chronological age and growth variables, such height, weight and pubertal stages. Aim: To evaluate the relationship between skeletal age and QUS variables and the influence of skeletal age on QUS variables after allowing for chronological age, height, weight and pubertal stage. Subjects and Methods: 235 healthy children and adolescents (85 boys and 150 girls) aged 3 - 18 years were examined. Height, weight, body mass index (BMI) were collected. Skeletal age was assessed by the third version of Tanner-Whitehouse method (TW3). QUS variables amplitude dependent speed of sound (AD-SoS, m/s) and bone transmission time (BTT, ∝sec) were measured by DBM Sonic BP IGEA sonograph. Results: Statistically significant positive correlations were found between AD-SoS and BTT and skeletal age (R2 = 0.76 in boys and 0.83 in girls for AD-SoS and 0.96 in boys and 0.93 in girls for BTT). A very close correlation was observed between skeletal age and BTT even after adjusting for chronological age, height, weight, and pubertal stage. In both sexes, chronological age, height and BTT resulted significant predictors of skeletal age. Conclusion: Skeletal age has emerged as an important determinant of phalangeal QUS measurements, mainly BTT. Skeletal maturity should be taken into account when QUS technology is used to evaluate bone mass and structure in children.

Impact on bone mineral density of tenofovir-containing HAART in HIV-1 infected children and adolescents: a report from 5 years of clinical experience

Purpose of the study Tenofovir disoproxil fumarate (TDF) is not approved for use in HIV-infected children (<18 years). In clinical practice a TAMs-sparing regimen may be needed. Use of TDF in children seems to be associated with decrease in bone mineral density that sometimes can stabilize after 24 weeks. The primary purpose was to characterized the change in bone mineral density (BMD), as measured by osteosonography (QUS), during and after treatment with tenofovir-containing HAART.