Intellectual performance in young adult males born small for gestational age

Children born small for gestational age (SGA) have increased risk of neurological dysfunction. The aim of this study was to analyze intellectual performance in early adult age in children born SGA, and especially the effect of catch up growth in height.

METHODS

Data on gestational age and birth size were taken from the Swedish Birth Register and data on adult height and intellectual performance from the Swedish Conscript Register.

RESULTS

Low birth weight, birth length and head circumference increased the risk of subnormal intellectual and psychological performance in males born SGA. Very low gestational age also increased the risk. However, the most important predictor was the absence of catch up growth to a height above -2 SDS in individuals born SGA.

Catch-Up Growth in Females Born Short for Gestational Age Reduces the Risk of Giving Birth to Short-for-Gestational-Age Infants

<i>Objectives: </i>The aim of the present study was to study the effect of catch-up growth on the offspring’s length at birth among females born short for gestational age. <i>Methods:</i> Data of 1,363 females born short for gestational age (<–2 standard deviation scores) were obtained from the Swedish Birth Register. The females were included in the register both as babies and mothers. The effect of catch-up growth on the offspring’s birth length was studied. <i>Results: </i>Short adult stature was associated with a threefold increase in the risk of giving birth to a short infant [OR 3.08 (CI 1.73–5.50)] and smoking increased the risk in a dose-dependent manner. Overweight was associated with a reduced risk [OR 0.46 (CI 0.22–0.96)] of giving birth to a short infant. <i>Conclusion:</i> Catch-up growth to normal adult stature among women born short for gestational age is associated with a reduced risk of giving birth to a short-for-gestational-age infant.

Treatment of extreme hyperglycemia monitored with intracerebral microdialysis

OBJECTIVE

Description of a pediatric patient with hyperosmolar hyperglycemic nonketotic syndrome where the treatment was monitored with intracerebral microdialysis.

DESIGN

Case report.

SETTING

Intensive care unit at a university hospital.

PATIENT

An 11-yr-old boy with new-onset diabetes who presented with a blood glucose concentration of 100 mmol/L (1800 mg/dL) and a serum osmolality of 448 mOsm/kg.

INTERVENTIONS

Interventions included intracerebral and subcutaneous microdialysis as well as intracranial pressure monitoring during correction of the hyperosmolar condition. The strategy was to decrease osmolality by 1 mOsm.kg(-1).hr(-1) and blood glucose by 1.5 mmol.L(-1).hr(-1) (27 mg/dL).

MEASUREMENTS AND MAIN RESULTS

The concentrations of glucose in the subcutaneous dialysates corresponded to the blood glucose concentrations. The brain/subcutaneous glucose ratio varied between 0.20 and 1.28 (mean, 0.43; median, 0.4). When the blood glucose decreased quickly after steady state, the brain/subcutaneous ratio increased sharply, demonstrating that the normalization of glucose in the brain was slower than that in blood.

CONCLUSIONS

Microdialysis can be used to monitor the brain/subcutaneous glucose ratio in patients with extreme hyperglycemia. A rapid decrease in blood glucose increases the brain/subcutaneous glucose ratio, which may be a potential risk factor for osmotic brain edema. Microdialysis may prove to be a valuable tool in treatment management. The child made a full recovery.

Intellectual and psychological performance in males born small for gestational age

All male singletons born without congenital malformations in Sweden between 1973 and 1978 and conscripted between January 1991 and January 1997 (n = 254426) were studied. Intellectual and psychological performance was tested at conscription. Males born small for gestational age (SGA) had lower results on both intellectual and psychological performance testing. Among males born SGA, low mean scores in both tests were constantly more common in those without catch-up growth than in those with catch-up growth. In conclusion, being born SGA is associated with an increased risk of subnormal intellectual and psychological performance. Catch-up growth is associated with a reduced risk of subnormal performance in males born SGA.

Birth characteristics and different dimensions of intellectual performance in young males: a nationwide population-based study

AIM

To study the effect of size at birth on different dimensions of intellectual capacity.

METHODS

The study comprised a population-based cohort including all male single births without congenital malformations in Sweden from 1973 to 1976, and conscripted before 1994 (n = 168 068). Information from the Swedish Birth Register was individually linked to the Swedish Conscript Register. The test of intellectual performance included four different dimensions: logical, spatial, theoretical and verbal capacity. These data were available for 80-86% of the males at conscription.

RESULTS

Compared with boys born appropriate for gestational age, males born small for gestational age (SGA) had an increased risk for subnormal performance in all four dimensions. Among males born SGA who were also of short adult stature at conscription, and in individuals born SGA with a head circumference <-- 2 SDS at birth, the risk of subnormal performance was most marked in the logical dimension (OR 1.52; CI 1.25-1.84 and 1.33; 1.15-1.55, respectively).

CONCLUSIONS

Being born small for gestational age is associated with increased risk of subnormal capacity in all four dimensions of intellectual performance. In SGA males, short adult stature, or a small head circumference at birth is especially associated with the risk of subnormal logical performance.

Prediction of adult height and risk of overweight in females born small-for-gestational-age

The risk of short adult stature in women born small-for-gestational age (SGA) was estimated in this prospective cohort study of 43 872 singleton females, born between 1973 and 1983, who gave birth to a child between 1989 and 1999. The risk of overweight in females born SGA, with and without short adult stature, was also studied. All data on birth characteristics and adult height and weight were obtained from the Swedish Birth Register. SGA-born females were divided into being born short only for gestational age [birth length < -2 standard deviation scores (SDS)], born light for gestational age (birthweight < -2 SDS) or being born both short and light for gestational age. Short adult stature was defined as adult height below -2 SDS. Among females, being born SGA (<-2 SDS in birth length or birthweight) was associated with increased risk of short adult stature, compared with being born appropriate for gestational age. The risk varied substantially within different subgroups of females born SGA: being born short for gestational age was associated with an almost fivefold increased risk [odds ratio (OR) 4.89; 95% confidence interval (CI) 3.70, 6.47] of short adult stature, whereas being born light for gestational age was associated with an almost twofold increased risk [OR 1.95, 95% CI 1.43, 2.65]. Overall, females born SGA did not have increased risk of overweight compared with females with appropriate size at birth. However, among females born short for gestational age, short adult stature was associated with an increased risk of overweight in adulthood [OR 1.77, 95% CI 1.01, 3.12]. In conclusion, among females born SGA, of the birth characteristics, short birth length is associated with the highest increased risk of short adult stature. Spontaneous growth in height to normal adult stature reduced the risk of overweight in females born short for gestational age.

Insulin sensitivity and lipolysis in adolescent girls with poorly controlled type 1 diabetes: effect of anticholinergic treatment

OBJECTIVES

Increased GH secretion could be one factor behind the impaired glycaemic control often seen in adolescent girls with type 1 diabetes. Because GH induces insulin resistance, treatment with anticholinergic agents, such as pirenzepine (PZP), has been used to reduce GH secretion. However, in a previous study of adolescent girls with type 1 diabetes, we observed an improvement in glycaemic control during 12 weeks of PZP therapy despite unchanged excretion of GH in urine. Considering the complex mechanisms behind urinary GH excretion, the effects of PZP on pituitary GH secretion or secretory pattern cannot be excluded. Thus, to assess the effect of anticholinergic treatment on metabolic control in adolescent girls with diabetes, we have investigated GH secretion, insulin sensitivity and lipolysis before and during treatment with PZP.

PATIENTS

Eleven adolescent girls with type 1 diabetes and poor metabolic control were investigated before and after treatment with PZP, 100 mg orally, twice a day for 3 weeks.

DESIGN

Serum samples for analysis of haemoglobin A1c and IGF-I were obtained in addition to serum profiles of GH, insulin and IGFBP-1 before and after 3 weeks of PZP treatment. Effects on insulin sensitivity and lipolysis were also assessed.

MEASUREMENTS

IGFBP-1 was measured every hour, whereas serum GH and insulin were measured every 20 min for 24 h. Insulin sensitivity was analysed with the hyperinsulinaemic euglycaemic clamp technique. The rate of lipolysis was assessed under basal conditions following a constant rate infusion of [1,1,2,3,3-2H5]-glycerol. In five girls, lipolysis was also estimated during the hyperinsulinaemic euglycaemic clamp.

RESULTS

There was a significant reduction in haemoglobin A1c levels (9.9 +/- 0.2%vs. 9.1 +/- 0.2; P < 0.0001) during 3 weeks of PZP treatment. In additional, the glucose requirement during the euglycaemic hyperinsulinaemic clamp increased by more than 30% (72.5 +/- 4.9 vs. 96.8 +/- 8.5 mg/m2/min; P = 0.003). However, we could not demonstrate any significant changes in GH secretion (area under the curve, basal levels or peak amplitude) or in the GH secretory pattern (peak height, peak length or interpeak interval). Concordantly, the IGF-I levels were statistically unchanged, as were IGFBP-1 concentrations. The rate of lipolysis did not change under basal conditions (3.40 +/- 0.53 vs. 3.04 +/- 0.54 micro mol/kg/min, n = 11, P = 0.54) or during the hyperinsulinaemic euglycaemic clamp (1.58 +/- 0.21 vs. 2.08 +/- 0.26 micro mol/kg/min; n = 5, P = 0.32).

CONCLUSIONS

Our observations of an increased glucose requirement during the clamp as well as a decrease in haemoglobin A1c demonstrate improved insulin sensitivity in the adolescent girls with diabetes following pirenzepine therapy. The mechanism behind the improvement is not clear, as neither secretion nor the secretory pattern of GH changed significantly. The persistently high levels of GH might explain the unaltered rate of lipolysis despite the improved insulin sensitivity. The observed improvement in glycaemic control in adolescent girls with type 1 diabetes following pirenzepine therapy is promising, although more studies on this topic are needed.

Suppression of puberty in girls with short-acting intranasal versus subcutaneous depot GnRH agonist

BACKGROUND/AIM

Central precocious puberty (CPP) is more common in females than in males. During the last few decades a new group of patients with CPP has been seen frequently in Northern Europe, namely children adopted from developing countries. GnRH analogue preparations, administered either as intranasal spray or as depot preparations, are the drugs of choice for inhibiting the release of gonadotropins. The aim of this study was to compare the effect of buserelin given by intranasal spray with that of the same compound given as a subcutaneous depot preparation.

METHODS

The study group comprised 46 pubertal girls below the age of 9.5 years, adopted from a developing country. During the first 2 years, the treatment used was buserelin acetate 300 microg 6 times daily as a nasal spray. During the third year the treatment was changed to Suprefact Depot, 6.3 mg, given as a subcutaneous implant every 8 weeks. Half of the girls were randomized to growth hormone treatment in addition to the pubertal inhibition.

RESULTS

GnRH provocation tests after 6 weeks, 1 year and 2 years of treatment with intranasal GnRH analogue showed suppression of gonadotropin secretion except in 1 case of noncompliance. During the third year, when the long-acting depot preparation was used, suppression was more pronounced. The peak LH response, especially, was considerably lower than during treatment with the nasal spray preparation. In all cases the clinical inhibition of puberty was adequate both during the first two years and during the third year.

CONCLUSION

Even though the clinical suppression of puberty was adequate with both modes of administration, the effect of the depot preparation, in this study Suprefact Depot, was more pronounced in terms of gonadotropin suppression and less dependent on patient compliance.

Enterovirus RNA is found in peripheral blood mononuclear cells in a majority of type 1 diabetic children at onset

We have studied the occurrence of enterovirus (EV)-RNA at the onset of childhood type 1 diabetes in all 24 new cases of childhood type 1 diabetes during 1 year in Uppsala county, Sweden. We also studied 24 matched control subjects and 20 siblings of the patients. RNA was isolated from peripheral blood mononuclear cells and EV-RNA detected by RT-PCR. Primers (groups A and B) corresponding to conserved regions in the 5' noncoding region (NCR) of EV were used in the PCRs, and the amplicons were sequenced. By the use of group A primers, EV-RNA was found in 12 (50%) of the 24 type 1 diabetic children, 5 (26%) of 19 siblings, and none of the control subjects. Both patients and siblings showed a higher frequency of EV-RNA compared with the control subjects. The group B primers detected EV-RNA in all three groups but did not show statistically significant differences between the groups. The EV-RNA positivity with the group B primers was 11 (46%) of 24 in the type 1 diabetic children, 11 (58%) of 19 in the siblings, and 7 (29%) of 24 in the control subjects. The significant difference between groups seen with the group A primers but not with the group B primers might indicate the existence of diabetogenic EV strains. The phylogenetic analysis of the PCR products revealed clustering of the sequences from patients and siblings into five major branches when the group A PCR primers were used. With the group B primers, the sequences from patients, siblings, and control subjects formed three major branches in the phylogenetic tree, where 6 of the 7 control subjects clustered together in a sub-branch of CBV-4/VD2921. Seven of the type 1 diabetic children clustered together in another sub-branch of CBV-4/VD2921. Five of the type 1 diabetic children formed a branch together with the CBV-4/E2 strain, four clustered together with CBV-5, and one formed a branch with echovirus serotype. The presence of EV-RNA in the blood cells of most newly diagnosed type 1 diabetic children supports the hypothesis that a viral infection acts as an exogenous factor. In addition, sequencing of the PCR amplicons from the type 1 diabetic children, their siblings, and matched control subjects might reveal differences related to diabetogenic properties of such a virus.

Diabetes control deteriorates in girls at cessation of growth: relationship with body mass index

AIM

Diabetic patients, particularly girls, often experience poor metabolic control during puberty and adolescence. The aim of this study was to investigate metabolic control during adolescence, especially in relation to pubertal stages, growth, insulin treatment and body mass index (BMI).

METHODS

We studied the records of 38 (consecutive) girls with prepubertal onset of Type 1 diabetes mellitus. Data from the age of 10 to 18-20 years were obtained with regard to glycaemic control, growth, age at menarche, final height and BMI, and analysed in relation to both chronological age and age at menarche.

RESULTS

HbA1c was lowest 3 years before menarche; mean (+/- sd) 7.6 (+/- 1.2). After the pubertal growth spurt, there was a marked impairment of metabolic control, the highest level of HbA1c occurring 3 years after menarche. Mean age at menarche was 13.3 (+/- 1.1) years and mean linear growth after menarche only 4.7 cm, giving a final height of 164.9 (+/- 5.3) cm which is 2.7 cm below the Swedish mean. During adolescence the degree of correlation between BMI and HbA1c continuously increased, pointing out the effect of body fat on metabolic control in this age group. The level of HbA1c at 10 years of age could not predict the metabolic control after cessation of puberty, but prepubertal BMI appears to be a risk factor for both obesity and poor glycaemic control in late adolescence.

CONCLUSIONS

The highest HbA1c was found after cessation of growth. Prepubertal BMI is a possible predictor of metabolic control in adolescent diabetic girls.

Intellectual and psychological performance in males born small for gestational age with and without catch-up growth

Infants born small for gestational age (SGA) have an increased risk of neurologic and intellectual dysfunction. Most of these infants catch up in growth and attain normal height, although some do not. Whether catch-up growth influences intellectual function is not known. To analyze whether intellectual and psychological performance of males in early adulthood are associated with body size at birth or by catch-up growth in height among boys, a population-based cohort was studied. This cohort included all male singletons born without congenital malformations in Sweden from 1973 to 1978 and alive at 18 y (n = 276,033). Information from the Swedish Birth Register was individually linked to the Swedish Conscript Register. Of 254,426 conscripted males, information on intellectual and psychological performance was available for 97% and 91%, respectively. Low birth weight, short birth length, small head circumference at birth, and preterm birth increased the risk of subnormal intellectual and psychological performance. Among SGA-born males, the most important predictor was the absence of catch-up growth. Being born SGA is associated with increased risk of subnormal intellectual and psychological performance. The data strongly support the view that, for males born SGA, it is an advantage to have catch-up growth in length.

Bladder capacity and renal concentrating ability in enuresis: pathogenic implications

PURPOSE

We compared bladder volume and renal concentrating capacity in dry children and 2 distinct groups of children with enuresis to hypothesize about the pathogenesis of various types of enuresis.

MATERIALS AND METHODS

A total of 55 dry children and 100 with enuresis underwent an overnight thirst provocation test to assess renal concentrating capacity and completed a 2-day voiding chart to assess functional bladder capacity. The enuretic children were subdivided into 27 desmopressin responders and 73 desmopressin nonresponders before study inclusion.

RESULTS

The desmopressin responder group had lower average renal concentrating capacity +/-1 standard deviation than dry children and desmopressin responders (856 +/- 158 mOsm./kg. versus 939 +/- 147 and 962 +/- 151, respectively, p <0.05). Analogously average daytime urine production in the desmopressin responder group was greater than in dry children and desmopressin responders (22.2 +/- 10.2 ml./kg. body weight versus 15.4 +/- 7.3 and 15.3 +/- 7.2, respectively, p <0.01). Average functional bladder capacity expected for age was less in desmopressin nonresponders than in dry children and responders (52.2% +/- 19.9% versus 79.2% +/- 30.4% and 69.5% +/- 25.7%, respectively, p <0.001).

CONCLUSIONS

Desmopressin responders produced larger amounts of less concentrated urine than the other children, while desmopressin nonresponders had smaller bladder capacity than the other groups. These results support the idea that enuretic children who respond favorably to desmopressin treatment have polyuria, whereas children with therapy resistant enuresis have detrusor hyperactivity.

Anticholinergic treatment improves glycaemic control in adolescent girls with insulin-dependent diabetes mellitus

Metabolic control often deteriorates during puberty in girls with insulin-dependent diabetes. It is well accepted that there is an abnormality in the growth hormone (GH)-insulin-like growth factor-I (lGF-I) axis in these girls, resulting in reduced IGF-I levels and elevated GH. As GH antagonizes insulin, attempts have previously been made to reduce excess GH secretion through anticholinergic treatment. However, most of these studies have been performed on adult patients. The aim of the present study was to evaluate the effects of 12 wk of oral anticholinergic treatment with Pirenzepine, 100 mg twice daily, in 16 adolescent girls with diabetes. Serum samples of IGF-I, glycated haemoglobin and fasting IGF-binding protein 1 were analysed at initiation and after 3, 8 and 12 wk of Pirenzepine therapy. Nocturnal urinary GH excretion was also examined. Glycated haemoglobin declined significantly after 3 wk of Pirenzepine therapy (9.8 +/- 0.18 vs 9.2 +/- 0.17; p < 0.001) and was still improved at the end of the study. Unexpectedly, nocturnal urinary GH excretion did not change. Serum IGF-I continuously increased during the study, while IGF-binding protein 1 levels were not significantly altered.

CONCLUSION

Anticholinergic treatment with Pirenzepine improves glycaemic control in adolescent girls with diabetes. Although nocturnal urinary GH excretion was unchanged there may still be changes in pituitary GH secretion to explain the improvement. Effects of Pirenzepine on gastrointestinal motility can represent other possible mechanisms behind the improved metabolic control.

Profound changes in the GH-IGF-I system in adolescent girls with IDDM: can IGFBP1 be used to reflect overall glucose regulation?

Disturbances in the relations between insulin, growth hormone (GH) and insulin-like growth factor I (IGF-I) may be a major cause behind deteriorated metabolic control in adolescent girls with type I diabetes. These patients have increased GH secretion and low IGF-I concentrations. The aim of this study was to identify possible endocrine mechanisms behind good and poor glycaemic control in such girls, focusing on the insulin-GH-IGF-I axis. Ten girls with well-controlled insulin-dependent diabetes mellitus (IDDM), hemoglobin A1c (HbA1c) 6.5+/-0.4% (normal range 3.9-5.2%) and nine healthy controls were investigated and compared with 11 girls with poor glucose regulation, HbA1c 10.9+/-0.4%, and their corresponding controls. Serum profiles of glucose, insulin, GH and IGF-binding protein 1 (IGFBP1) were analysed in addition to IGF-I and HbA1c. Two interesting observations were made. GH concentrations were equally elevated in the two diabetic groups regardless of metabolic control (mean 24 h GH - girls with poorly controlled diabetes 10.0+/-1.0 mU/L vs 9.8+/-1.7 - girls with well-controlled diabetes; p=ns). Likewise, the IGF-I concentrations were reduced to the same extent (233+/-19 vs 242+/-23 microg/L; p=0.75). Secondly, despite similar insulin concentrations (mean 24 h insulin - girls with poorly controlled diabetes 22.9+/-2.6 and girls with well-controlled diabetes 27.3+/-2.9 mU/L, respectively; p=0.26), there was a marked difference in IGFBP1 concentrations between the two groups with IDDM (mean IGFBP1 - girls with poorly controlled diabetes 70.5+/-9.1 microg/L vs girls with well-controlled diabetes 28.6+/-3.3; p<0.001). Despite equally elevated GH concentrations that may induce insulin resistance, the markedly lower concentrations of IGFBP1 in the well-controlled group indicate a higher hepatic insulin sensitivity in these girls compared with those with a poor control. Furthermore, in spite of similar total IGF-I concentrations, the lower IGFBP1 concentrations may result in higher IGF-I bioactivity in the well-controlled group. This may be reflected in better growth of the well-controlled group whose height of 168.7+/-0.9 vs 163.6+/-1.2 cm was significantly different (p<0.004). IGFBP1 may be a marker of overall insulinization in adolescents with type 1 diabetes, independent of the absolute insulin dose used for therapy.

Prepubertal growth and growth hormone secretion in children after treatment for hematological malignancies, including autologous bone marrow transplantation

Prepubertal growth standards were used to assess growth in 20 children who had undergone autologous bone marrow transplantation (ABMT) as part of their treatment for hematological malignancy. Most of the patients (16 of 20) were transplanted after a relapse of their disease. A negative change in height standard deviation score (H-SDS) was seen only in the group of patients (n = 7) who had received both cranial irradiation therapy (CRT) and 7.5-Gy single-fraction total body irradiation (TBI). Height changes in this group were observed from the time of diagnosis. In contrast, the groups of patients conditioned with chemotherapy only (n = 3) or both chemotherapy and TBI, without preceding CRT (n = 10), did not demonstrate a significant loss in H-SDS. Weight related to height demonstrated large individual differences over time. Spontaneous growth hormone (GH) secretion, as measured by a four-point sleep curve, was followed longitudinally and an increasing proportion of patients with low peak levels was seen in all patient groups. In summary, prepubertal growth was suppressed only in patients who received cranial irradiation before ABMT. Despite low GH peak levels, normal prepubertal growth was found in patients with no CRT before ABMT.

Intellectual and physical performance and morbidity in relation to height in a cohort of 18-year-old Swedish conscripts

To test whether short stature in young men without malformations or chronic childhood diseases is associated with intellectual and physical performance and morbidity, a large cohort of apparently healthy 18-year-old Swedish men was analysed. The original cohort consisted of all men born in 1976 and conscripted in 1994 (n = 38, 900). After exclusion due to growth-affecting disorders or missing data, 32,887 subjects were available for analysis. Short conscripts (height below or equal to -2 SD scores) demonstrated increased overall morbidity compared with taller conscripts (above -2 SD scores). Specifically, short conscripts had more psychiatric and musculoskeletal diagnoses and were more often considered psychologically unsuitable for military service. Mean intellectual performance increased continuously with height; the mean 'standard nine' score was 4.22 for the short men and 5.17 for the rest (p < 0. 001). Short conscripts scored less well than taller conscripts in assessment of psychological functioning during mental stress, and were evaluated as less suitable for leadership positions. Maximal working capacity per kilogramme body weight correlated negatively with height (p < 0.001). In conclusion, short stature was associated with increased morbidity and psychological problems and with lower mean intellectual performance. To what extent this association is direct or indirect needs further evaluation.

Growth hormone therapy in young children with Down syndrome and a clinical comparison of Down and Prader-Willi syndromes

The genetic disorders Prader-Willi syndrome and Down syndrome have a number of features in common, for example, both growth and mental retardation. Growth hormone (GH) treatment is becoming part of the clinical management of children with Prader-Willi syndrome, but in children with Down syndrome, such therapy is still on a research level. In this review, we compare the clinical phenotypes of the two syndromes, and report the effects of long-term GH treatment on the linear growth and psychomotor development of 15 young children with Down syndrome (mean age at start of treatment, 7.4 months). The mean height of the treated children with Down syndrome increased significantly from -1.8 to -0.8 SDS (Swedish standard) during the 3 years of GH therapy (P < 0.001). The mean height of a corresponding control group fell from -1.7 to -2.2 SDS. After the cessation of treatment, growth velocity declined in the treated group. Growth of the head did not increase during GH treatment. There was no effect on mental or gross-motor development, although some improvement in fine-motor development was noted in the GH-treated group (P < 0.01). At present, treatment with GH is not recommended in children with Down syndrome who have not been diagnosed with GH deficiency. Long-term studies with an emphasis also on the metabolic effects of GH therapy are necessary before routine treatment can be considered in such children.

Enuresis--background and treatment

Nocturnal urinary continence is dependent on 3 factors: 1) nocturnal urine production, 2) nocturnal bladder function and 3) sleep and arousal mechanisms. Any child will suffer from nocturnal enuresis if more urine is produced than can be contained in the bladder or if the detrusor is hyperactive, provided that he or she is not awakened by the imminent bladder contraction. Urine production is regulated by fluid intake and several interrelated renal, hormonal and neural factors, foremost of which are vasopressin, renin, angiotensin and the sympathetic nervous system. Detrusor function is governed by the autonomic nervous system which under ideal conditions is under central nervous control. Arousal from sleep is dependent on the reticular activating system, a diffuse neural network that translates sensory input into arousal stimuli via brain stem noradrenergic neurons. Disturbances in nocturnal urine production, bladder function and arousal mechanisms have all been firmly implicated as pathogenetic factors in nocturnal enuresis. The group of enuretic children are, however, pathogenetically heterogeneous, and two main types can be discerned: 1) Diuresis-dependent enuresis - these children void because of excessive nocturnal urine production and impaired arousal mechanisms. 2) Detrusor-dependent enuresis - these children void because of nocturnal detrusor hyperactivity and impaired arousal mechanisms. The main clinical difference between the two groups is that desmopressin is usually effective in the former but not in the latter. There are two first-line therapies in nocturnal enuresis: the enuresis alarm and desmopressin medication. Promising second-line treatments include anticholinergic drugs, urotherapy and treatment of occult constipation.

Desmopressin resistant enuresis: pathogenetic and therapeutic considerations

PURPOSE

We tested the role of the bladder in the pathogenesis of desmopressin resistant enuresis by evaluating the influence of urine production on the timing of the enuretic event and the response to anticholinergic medication.

MATERIALS AND METHODS

We gave 33 children with monosymptomatic nocturnal enuresis resistant to the standard 0.4 mg. oral dose of desmopressin 0.4 and 0.8 mg. desmopressin and placebo tablets for 5 nights each in a double-blind crossover fashion. The time of enuresis or nocturia was documented. All 9 children who had at least 1 dry treatment period during the randomized portion of the study then received open label treatment with 0.8 mg. desmopressin. Nonresponders to this regimen and the remainder of the children were offered anticholinergic treatment.

RESULTS

Average time between bedtime and voiding was 5.0, 5.6 and 5.0 hours during the nights with placebo, and 0.4 and 0.8 mg. desmopressin, respectively (p = 0.12). Of the 9 children subsequently treated with 0.8 mg. desmopressin 5 became completely dry. Of the remaining 28 children given anticholinergic treatment 20 responded.

CONCLUSIONS

Antidiuresis does not delay the enuretic event in children with desmopressin resistant enuresis. This finding and the favorable response to anticholinergic medication favor the hypothesis that these children have nocturnal bladder instability. A subgroup of enuretic children responds to high but not normal doses of desmopressin.

Prediction of male adult stature using anthropometric data at birth: a nationwide population-based study

Short stature and excess weight in adulthood are both associated with an increased risk of health problems. In a population-based investigation, data on birth length, birth weight, and gestational age for males born in Sweden in 1976 were used to predict the risk of being short or overweight in adulthood. The Swedish Birth Register was used to identify singleton males, born to Nordic mothers, who were without malformations and alive at 18 y of age. After individual record linkage between the Birth Register and the Swedish Conscript Register, information about height and weight at 18-21 y was obtained for 90% (n = 39901) of the birth cohort. Logistic regression analyses were used to estimate the risk of being short or overweight at conscription. The odds ratio (OR) was used to estimate relative risk. At conscription, mean height (+/-SD) was 179.5+/-6.6 cm, mean weight 72.1+/-11.2 kg, and mean body mass index 22.3+/-3.1 kg/m2. The risk of short adult stature (<166.3 cm) was associated with being short for gestational age (OR = 5.9), having a low birth weight for gestational age (OR = 1.7), and being born at a gestational age below 32 wk (OR = 2.6). The risk of being overweight (body mass index > +2 SD) was primarily associated with a high ponderal index (> +2 SD; OR = 1.8). In conclusion, anthropometric birth data are better predictors of short stature than of being overweight in adulthood. Among anthropometric data at birth, birth length is the most important predictor of adult height.

Influence of perinatal factors on the onset of puberty in boys and girls: implications for interpretation of link with risk of long term diseases

The authors examined the hypothesis that perinatal factors influence the onset of puberty. Children born as singletons in Uppsala, Sweden, in 1973-1977 were followed for height development before and during their school years (through 16 years of age). In all, 62 children born after preeclampsia, 129 born prematurely, 90 born small for gestational age, 175 born large for gestational age, 49 born short for gestational age, and 38 born tall for gestational age were compared with 688 "normal" children. Differences in age and height at puberty onset and age at menarche were analyzed using the t test and analyses of covariance. For boys, the mean age at puberty onset did not differ between normal boys and those with perinatal factors. Boys born small or short for gestational age were 4 cm shorter than normal boys, and those born large for gestational age were 3 cm taller than normal boys. Among girls, patterns for differences in height were similar. Girls born small for gestational age were 5 months younger than normal girls at the onset of puberty and menarche. Patterns of early childhood growth seemed to explain the relations between these perinatal factors and height and age at puberty. The authors conclude that body size at birth affects stature at puberty; in girls, smallness for gestational age is associated with earlier puberty. Associations between intrauterine exposures and disease risk may be confounded by, or mediated through, effects on adolescence.

Growth hormone treatment during suppression of early puberty in adopted girls. Swedish Growth Hormone Advisory Group

Girls adopted from developing countries often have early or precocious puberty, requiring treatment with gonadotropin-releasing hormone (GnRH) analogues. During such treatment decreased growth velocity is frequent. The aim of this investigation was to study whether the addition of growth hormone (GH) to GnRH analogue treatment improves height velocity and final height in girls with early or precocious puberty. Forty-six girls with early or precocious puberty adopted from developing countries were randomized for treatment with GnRH analogue or a combination of GH and GnRH analogue. After 2 y of treatment the mean growth in the GH/GnRH analogue group was significantly higher, 14.6 cm, compared to 10.9 cm in the control group. The increase in bone age did not differ, while the difference in predicted adult height increased by 2.7 cm in favour of the combination group. Although data on final height are not yet available, combined GH/GnRH analogue treatment for 2 y resulted in a higher growth velocity and predicted final height compared to GnRH analogue treatment alone.

Prevalence of coeliac disease in Turner syndrome

This study was undertaken to investigate the prevalence of coeliac disease in children and adolescents with Turner syndrome. Eighty-seven children and adolescents with Turner syndrome were screened for IgA-antiendomysium antibodies (EMA) and IgA-antigliadin antibodies (AGA), 5% (4/87) being found to be EMA-positive, and 15% (13/87) to have AGA levels above normal. Of the 10 patients who were either AGA- or EMA-positive and further investigated with intestinal biopsy, four manifested villous atrophy (i.e. all three of the EMA-positive patients, but only one of the seven AGA-positive patients). The results suggest EMA-positivity to be a good immunological marker for use in screening for coeliac disease, and such screening to be justified in patients with Turner syndrome.