Low-density lipoprotein subclasses over the menopausal transition and risk of coronary calcification and carotid atherosclerosis: the SWAN Heart and HDL ancillary studies.

OBJECTIVE: Perimenopausal women experience a steep increase in low-density lipoprotein cholesterol (LDL-C) that is related to a higher risk of carotid plaque later in life. Low-density lipoprotein subclasses have been linked to cardiovascular diseases beyond LDL-C, promising a better risk stratification. We aim to characterize changes in LDL subclasses and assess their associations with presence of coronary artery calcium (CAC score ≥10) and carotid intima-media thickness (cIMT) over the menopausal transition (MT) and by menopause stage. METHODS: Nuclear magnetic resonance spectroscopy LDL subclasses were measured for a maximum of five time points. Coronary artery calcification and cIMT were measured for a maximum of two time points. LOESS (locally weighted regression with scatter smoothing) plots, linear mixed-effects models, and generalized estimating equations were used for analyses. RESULTS: The study included 471 women (baseline: age, 50.2 ± 2.7 years; 79.0% premenopausal/early perimenopausal), of whom 221 had data on CAC or cIMT. Low-density lipoprotein subclasses increased over the MT, whereas intermediate density-lipoprotein particles declined. In adjusted models, higher total LDL particles (LDL-P) and apolipoprotein B were associated with greater CAC prevalence and greater cIMT. Although none of the associations were modified by menopause stage, higher LDL-C, apolipoprotein B, and total LDL-P were associated with greater cIMT during the perimenopause or postmenopause stages, whereas higher LDL-C and small LDL-P were associated with greater CAC prevalence, mainly during perimenopause. CONCLUSIONS: During the MT, women experience significant increases in LDL subclasses found to be related to greater cIMT levels and CAC prevalence. Whether these changes could better predict future risk of hard cardiovascular disease events beyond LDL-C remains a research question to address.

Utility of Repeat Testing for Congenital Hypothyroidism in Infants with Very Low Birth Weight.

OBJECTIVE: To assess for possible missed hypothyroidism in infants of very low birth weight (VLBW) whose initial newborn screening (NBS) was within normal reference range. STUDY DESIGN: We analyzed serum thyroid-stimulating hormone (TSH) obtained at 36 weeks of corrected gestational age or at hospital discharge if earlier (retest TSH) in infants with VLBW in the neonatal intensive care unit to determine the prevalence and factors associated with retest TSH ≥5 mU/L, a concentration requiring close follow-up for hypothyroidism. Utility of alternative cut-offs for NBS TSH also was assessed. RESULTS: A total of 398 infants, median gestational age 29 (range 22-36) weeks, birth weight 1138 (470-1498) g, were included in this study. Retest TSH was obtained at 49.5 (12-137) days after birth. Median retest TSH was 3.1 (0.5-27.9) mU/L. Seventy-three (18.3%) of the cohort had retest TSH ≥5 mU/L. Adjusting NBS cut-off to ≥15 or ≥10 mU/L identified <50% of infants with TSH ≥5 mU/L, resulting in 6% false positives and >70% false negatives. Multiple regression modeling indicated that 35% of variance in retest TSH value was explained by NBS TSH concentration, birth weight, and gestational age, all P < .01. CONCLUSIONS: Retesting for hypothyroidism at 36 weeks of corrected gestational age in infants with VLBL and normal NBS could identify infants who require ongoing surveillance until thyroid function has been definitively ascertained. Adjusting NBS TSH cutoffs is not a valid option for identifying potential hypothyroidism in infants with VLBW because of lack of sensitivity and unacceptable false-positive and false-negative rates.

Postmenopausal Women With Greater Paracardial Fat Have More Coronary Artery Calcification Than Premenopausal Women: The Study of Women's Health Across the Nation (SWAN) Cardiovascular Fat Ancillary Study.

BACKGROUND: Volumes of paracardial adipose tissue (PAT) and epicardial adipose tissue (EAT) are greater after menopause. Interestingly, PAT but not EAT is associated with estradiol decline, suggesting a potential role of menopause in PAT accumulation. We assessed whether volumes of heart fat depot (EAT and PAT) were associated with coronary artery calcification (CAC) in women at midlife and whether these associations were modified by menopausal status and estradiol levels. METHODS AND RESULTS: EAT and PAT volumes and CAC were measured using electron beam computed tomography scans. CAC was evaluated as (1) the presence of CAC (CAC Agatston score ≥10) and (2) the extent of any CAC (log CAC Agatston score >0). The study included 478 women aged 50.9 years (58% pre- or early perimenopausal, 10% late perimenopausal, and 32% postmenopausal). EAT was significantly associated with CAC measures, and these associations were not modified by menopausal status or estradiol. In contrast, associations between PAT and CAC measures were modified by menopausal status (interaction-P≤0.01). Independent of study covariates including other adiposity measures, each 1-SD unit increase in log PAT was associated with 102% higher risk of CAC presence (P=0.04) and an 80% increase in CAC extent (P=0.008) in postmenopausal women compared with pre- or early perimenopausal women. Additional adjustment for estradiol and hormone therapy attenuated these differences. Moreover, the association between PAT and CAC extent was stronger in women with lower estradiol levels (interaction P=0.004). CONCLUSIONS: The findings suggest that PAT is a potential menopause-specific coronary artery disease risk marker, supporting the need to monitor and target this fat depot for intervention in women at midlife.

Attention-Deficit/Hyperactivity Disorder Medication Treatment Impact on Response to Growth Hormone Therapy: Results from the ANSWER Program, a Non-Interventional Study.

OBJECTIVE: To examine whether attention-deficit/hyperactivity disorder (ADHD) stimulant medication modified the linear growth response to growth hormone (GH) treatment in children enrolled in the American Norditropin Studies: Web-Enabled Research Program. STUDY DESIGN: Short, GH treatment-naive children with or without GH deficiency (GHD) received GH therapy. A subset also received ADHD stimulant medication (n = 1190), and others did not (n = 7230). Linear mixed models (adjusted means) examined height SDS (HSDS) and body mass index (BMI) SDS from baseline through year 4. Analyses were repeated with ADHD groups matched for baseline age, height, weight, BMI, and sex. Groups with and without GHD were compared between ADHD groups. RESULTS: Adjusted change in HSDS for the group receiving ADHD stimulant medication was slightly lower than that for patients not receiving stimulant medication at years 1 to 4 (P < .05). However, adjusted change in HSDS was similar between children receiving and not receiving ADHD stimulant medication when matched for baseline measurements. At year 4, 86.7% of patients receiving ADHD stimulant medication, 86.8% of total patients not receiving ADHD stimulant medication, and 84.6% of matched group patients not receiving ADHD stimulant medication achieved HSDS >-2. Year 4 adjusted change in BMI SDS was greater in the patients receiving ADHD stimulant medication compared with both groups not receiving ADHD stimulant medication (P < .05). Patients with GHD showed comparable differences in adjusted change in BMI SDS among the ADHD groups at year 4, whereas patients without GHD showed no significant differences. CONCLUSIONS: ADHD medication did not affect the linear growth response of children treated with GH when those receiving or not receiving ADHD stimulant medication were matched for baseline measurements. Underlying reasons for the observed greater increase in BMI in patients with GHD concomitantly treated with ADHD medication remain to be elucidated. TRIAL REGISTRATION: ClinicalTrials.gov: NCT01009905.

Endocrine evaluation of children with and without Shwachman-Bodian-Diamond syndrome gene mutations and Shwachman-Diamond syndrome.

OBJECTIVE: To characterize the endocrine phenotype of patients with Shwachman-Diamond syndrome (SDS). STUDY DESIGN: Clinically indicated endocrine screening data from 43 patients with SDS or SDS-like presentation were analyzed according to sex, age, and genetic testing. In addition to 25 patients with biallelic Shwachman-Bodian-Diamond syndrome (SBDS) gene mutations, we evaluated 18 patients with cytopenias who were receiving pancreatic enzyme replacement but were without SBDS mutation. We performed a retrospective review of growth records and clinically indicated endocrine evaluations. RESULTS: Of patients with SBDS mutations, 2 had low stimulated growth hormone levels, 2 had mildly elevated thyrotropin levels, 5 had abnormal glucose levels, and 1 had an elevated follicle-stimulating hormone level (post transplantation). In contrast, 1 patient without SBDS mutations had postprandial hyperglycemia and 3 had mildly low free thyroxine levels without short stature. Endocrine abnormalities were identified in 19% of short patients and 26% of the whole group. Of patients with SBDS mutations, 56% had a height expressed in SD units from the mean for age and sex of <-1.8, in contrast to only 12% of patients without SBDS mutations (38% of the whole group). Body mass index z score was significantly greater in the group with SBDS mutations (P<.001). CONCLUSION: Although short stature was more common in patients with SBDS mutations, no consistent endocrine phenotype was observed in patients with SDS regardless of genetic testing.

Endocrine dysfunction following traumatic brain injury in children.

OBJECTIVE: To identify the incidence of endocrine dysfunction in children following traumatic brain injury (TBI). STUDY DESIGN: This was a prospective evaluation of 31 children after TBI. Inclusion criteria included Glasgow Coma Scale score ≤ 12 and age 1.5-18 years. We evaluated thyroid function, insulin-like growth factor I, insulin-like growth factor-binding protein 3, and cortisol at 1, 3, 6, and 12 months after injury, and assessed prolactin at 3 and 6 months. At 6 months, we also assessed overnight spontaneous growth hormone secretion, nocturnal thyrotropin surge, adrenal reserve, and serum and urine osmolarity. RESULTS: The average patient age was 11.6 years, and mean Glascow Coma Scale score was 6. The incidence of endocrine dysfunction was 15% at 1 month, 75% at 6 months, and 29% at 12 months. At 12 months after injury, 14% had precocious puberty, 9% had hypothyroidism, and 5% had growth hormone deficiency. Endocrine dysfunction at 1 year did not correlate with the severity of injury. CONCLUSIONS: Endocrine dysfunction after TBI is common in children, but most cases resolve by 1 year. We recommend endocrine surveillance at both 6 and 12 months following moderate or severe TBI to ensure early intervention for persistent or late-occurring endocrine sequelae.

Improved diagnosis of mild hypothyroidism using time-of-day normal ranges for thyrotropin.

OBJECTIVE: To assess clinical utility of time-of-day-based thyrotropin (TSH) ranges. STUDY DESIGN: Ranges for TSH at 8 am, 4 pm, and am/pm TSH ratio were developed from prior data in 94 typical children (age, 5 to 18 years). Data for these values in 227 short children (1.5 to 18 years) were compared with those in typical children. RESULTS: Short children included idiopathic short stature (ISS, n=153), central hypothyroidism (Central, n=42), and mild primary hypothyroidism (Primary, n=32), referred for evaluation of growth. In typical children, ISS, and Primary, 8 am TSH was greater than 4 pm TSH (P<.05). In Primary, 8 am TSH was greater than normal. Only 4 with Primary had elevated 4 pm TSH (using usual laboratory range of 0.5 to 4 mU/L). In contrast, only 63% of 4 pm TSHs in Primary were elevated. compared with 95% confidence limits in typical children. In Central, 8 am TSH and 4 pm TSH were within normal time-of-day range, and FT4 was in lowest one-third of normal. am/pm TSH ratio was less than 95% confidence limits in 76% of those with Central. CONCLUSIONS: Either 8 am TSH or 4 pm TSH (compared with time-of-day normal range) can identify TSH elevation. Low am/pm TSH ratio (FT4 in lowest one-third of normal) confirms central hypothyroidism. Thus, time-of-day TSH ranges should be used for accurate diagnosis and more appropriate cost-effective treatment of mild hypothyroidism.

Autoimmune thyroiditis in 18q deletion syndrome.

Deletion of a segment of the long arm of chromosome 18 causes characteristic physical features and mental retardation. Autoimmune disorders have been described with this syndrome in a limited number of reports. We describe 2 cases of autoimmune hypothyroidism in children with 18q deletion syndrome.

Autoimmune thyroiditis during leuprolide acetate treatment.

Autoimmune thyroiditis developed in a 9-year-old girl with precocious puberty approximately 8 months after initiation of Leuprolide acetate therapy. In addition, gonadotropin concentrations as measured by radioimmunoassay appeared high. Treatment with levothyroxine, in addition to continued Leuprolide acetate treatment, resolved gonadotropin elevation and hypothyroidism.

The building blocks of cognition.

This article provides an overview of some innovative ways of examining infant cognition, highlighting several procedures that are likely to prove useful for assessing the effects of interventions in the first year of life. The procedures singled out assess three aspects of cognition in infancy: visual recognition memory, attention, and speed of processing. Assessments of each, while primarily experimental in nature, show strong developmental change over the first year, as well as modest stability, discriminant validity, and predictive validity. The emerging evidence suggests that these three aspects of infant cognition are among the most basic building blocks of mature cognition.