Pre-pregnancy overweight or obesity and gestational diabetes as predictors of body composition in offspring twenty years later: evidence from two birth cohort studies.

BACKGROUND: Global prevalence of overweight/obesity and gestational diabetes (GDM) is increasing. In pregnant women both conditions affect offspring's later health. Overweight/obesity is a risk factor of GDM; to what extent maternal overweight/obesity explains long-term effects of GDM in offspring is unknown. OBJECTIVE: To evaluate effects of maternal pre-pregnancy overweight/obesity (body mass index (BMI) ⩾25 kg m-2) and GDM, occurring together or separately, on body composition among adult offspring. METHODS: Participants include 891 individuals aged 24.1 years (s.d. 1.4) from two longitudinal cohort studies (ESTER and AYLS). Adult offspring of normoglycemic mothers with overweight/obesity (ONOO, n=153), offspring of mothers with GDM (OGDM; n=191) and controls (n=547) underwent anthropometric measurements and bioimpedance analysis. Gestational diabetes mellitus was diagnosed by oral glucose tolerance test. Data were analyzed by linear regression models adjusted for confounders. RESULTS: Compared with controls, ONOO-participants showed higher BMI (men 1.64 kg m-2 (95% confidence interval 0.57, 2.72); women 1.41 kg m-2 (0.20, 2.63)) and fat percentage (men 2.70% (0.99, 4.41); women 2.98% (0.87, 5.09)) with larger waist circumferences (men 3.34 cm (0.68, 5.99); women 3.09 cm (0.35, 5.83)). Likewise, OGDM-participants showed higher fat percentage (men 1.97% (0.32, 3.61); women 2.32% (0.24, 4.41)). Body mass index was non-significantly different between OGDM-participants and controls (men 0.88 kg m-2 (-0.17, 1.92); women 0.82 kg m-2 (-0.39, 2.04)). Also waist circumferences were larger (men 2.63 cm (-0.01, 5.28); women 3.39 cm (0.60, 6.18)); this difference was statistically significant in OGDM-women only. Differences in body composition measures were stronger among offspring of women with both GDM and overweight/obesity. For instance, fat mass was higher among OGDM-participants of overweight mothers (men 4.24 kg (1.36, 7.11) vs controls; women 5.22 kg (1.33, 9.11)) than OGDM participants of normal weight mothers (men 1.50 kg (-2.11, 5.11) higher vs controls; women 1.57 kg (-3.27, 6.42)). CONCLUSIONS: Maternal pre-pregnancy overweight and GDM are associated with unhealthy body size and composition in offspring over 20 years later. Effects of maternal pre-pregnancy overweight appear more pronounced.

Autism spectrum traits and visual processing in young adults with very low birth weight: the Helsinki Study of Very Low Birth Weight adults.

Visual processing problems may be one underlying factor for cognitive impairments related to autism spectrum disorders (ASDs). We examined associations between ASD-traits (Autism-Spectrum Quotient) and visual processing performance (Rey-Osterrieth Complex Figure Test; Block Design task of the Wechsler Adult Intelligence Scale-III) in young adults (mean age=25.0, s.d.=2.1 years) born preterm at very low birth weight (VLBW; <1500 g) (n=101) or at term (n=104). A higher level of ASD-traits was associated with slower global visual processing speed among the preterm VLBW, but not among the term-born group (P<0.04 for interaction). Our findings suggest that the associations between ASD-traits and visual processing may be restricted to individuals born preterm, and related specifically to global, not local visual processing. Our findings point to cumulative social and neurocognitive problems in those born preterm at VLBW.

Childhood cognitive ability and body composition in adulthood.

BACKGROUND: Childhood cognitive ability has been identified as a novel risk factor for adulthood overweight and obesity as assessed by adult body mass index (BMI). BMI does not, however, distinguish fat-free and metabolically harmful fat tissue. Hence, we examined the associations between childhood cognitive abilities and body fat percentage (BF%) in young adulthood. METHODS: Participants of the Arvo Ylppö Longitudinal Study (n=816) underwent tests of general reasoning, visuomotor integration, verbal competence and language comprehension (M=100; s.d.=15) at the age of 56 months. At the age of 25 years, they underwent a clinical examination, including measurements of BF% by the InBody 3.0 eight-polar tactile electrode system, weight and height from which BMI (kg m(-2)) was calculated and waist circumference (cm). RESULTS: After adjustments for sex, age and BMI-for-age s.d. score at 56 months, lower general reasoning and visuomotor integration in childhood predicted higher BMI (kg m(-2)) increase per s.d. unit decrease in cognitive ability (-0.32, 95% confidence interval -0.60,-0.05; -0.45, -0.75,-0.14, respectively) and waist circumference (cm) increase per s.d. unit decrease in cognitive ability (-0.84, -1.56,-0.11; -1.07,-1.88,-0.26, respectively) in adulthood. In addition, lower visuomotor integration predicted higher BF% per s.d. unit decrease in cognitive ability (-0.62,-1.14,-0.09). Associations between general reasoning and BMI/waist were attenuated when adjusted for smoking, alcohol consumption, intake of fruits and vegetables and physical activity in adulthood, and all associations, except for visuomotor integration and BMI, were attenuated when adjusted for parental and/or own attained education and/or birth weight. CONCLUSIONS: Of the measured childhood cognitive abilities, only lower visuomotor integration was associated with BF% in adulthood. This challenges the view that cognitive ability, at least when measured in early childhood, poses a risk for adiposity in adulthood, as characterized by higher BF%.

Common mental disorders in young adults born late-preterm.

BACKGROUND: Results of adulthood mental health of those born late-preterm (34 + 0-36 + 6 weeks + days of gestation) are mixed and based on national registers. We examined if late-preterm birth was associated with a higher risk for common mental disorders in young adulthood when using a diagnostic interview, and if this risk decreased as gestational age increased. METHOD: A total of 800 young adults (mean = 25.3, s.d. = 0.62 years), born 1985-1986, participated in a follow-up of the Arvo Ylppö Longitudinal Study. Common mental disorders (mood, anxiety and substance use disorders) during the past 12 months were defined using the Composite International Diagnostic Interview (Munich version). Gestational age was extracted from hospital birth records and categorized into early-preterm (<34 + 0, n = 37), late-preterm (34 + 0-36 + 6, n = 106), term (37 + 0-41 + 6, n = 617) and post-term (⩾42 + 0, n = 40). RESULTS: Those born late-preterm and at term were at a similar risk for any common mental disorder [odds ratio (OR) 1.11, 95% confidence interval (CI) 0.67-1.84], for mood (OR 1.11, 95% CI 0.54-2.25), anxiety (OR 1.00, 95% CI 0.40-2.50) and substance use (OR 1.31, 95% CI 0.74-2.32) disorders, and co-morbidity of these disorders (p = 0.38). While the mental disorder risk decreased significantly as gestational age increased, the trend was driven by a higher risk in those born early-preterm. CONCLUSIONS: Using a cohort born during the advanced neonatal and early childhood care, we found that not all individuals born preterm are at risk for common mental disorders in young adulthood - those born late-preterm are not, while those born early-preterm are at a higher risk. Available resources for prevention and intervention should be targeted towards the preterm group born the earliest.

Late preterm birth, post-term birth, and abnormal fetal growth as risk factors for severe mental disorders from early to late adulthood.

BACKGROUND: Late preterm births constitute the majority of preterm births. However, most evidence suggesting that preterm birth predicts the risk of mental disorders comes from studies on earlier preterm births. We examined if late preterm birth predicts the risks of severe mental disorders from early to late adulthood. We also studied whether adulthood mental disorders are associated with post-term birth or with being born small (SGA) or large (LGA) for gestational age, which have been previously associated with psychopathology risk in younger ages. METHOD: Of 12 597 Helsinki Birth Cohort Study participants, born 1934-1944, 664 were born late preterm, 1221 post-term, 287 SGA, and 301 LGA. The diagnoses of mental disorders were identified from national hospital discharge and cause of death registers from 1969 to 2010. In total, 1660 (13.2%) participants had severe mental disorders. RESULTS: Individuals born late preterm did not differ from term-born individuals in their risk of any severe mental disorder. However, men born late preterm had a significantly increased risk of suicide. Post-term birth predicted significantly increased risks of any mental disorder in general and particularly of substance use and anxiety disorders. Individuals born SGA had significantly increased risks of any mental and substance use disorders. Women born LGA had an increased risk of psychotic disorders. CONCLUSIONS: Although men born late preterm had an increased suicide risk, late preterm birth did not exert widespread effects on adult psychopathology. In contrast, the risks of severe mental disorders across adulthood were increased among individuals born SGA and individuals born post-term.

Maternal hypertensive disorders during pregnancy: adaptive functioning and psychiatric and psychological problems of the older offspring.

OBJECTIVE: To study whether pre-eclampsia and hypertension without proteinuria during pregnancy are associated with adaptive functioning, and psychiatric and psychological problems, of older offspring. DESIGN: Retrospective longitudinal cohort study. SETTING: Participants in the Helsinki Birth Cohort 1934-44 Study. POPULATION: A cohort of 778 participants born after normotensive, pre-eclamptic, or hypertensive pregnancies, defined based on the mother's blood pressure and urinary protein measurements at maternity clinics and birth hospitals. METHODS: Pearson's chi-squared tests and multivariable logistic regression. MAIN OUTCOME MEASURES: Achenbach System of Empirically Based Assessment Older Adult Self-Report scores, completed at age 69.3 years (SD 3.1 years). RESULTS: Compared with offspring born after normotensive pregnancies, offspring born after pre-eclamptic pregnancies had increased odds of reporting total problems (aOR 4.00, 95%CI 1.64-9.77) and problems of particular concern to clinicians (critical items; aOR 5.28, 95%CI 1.87-14.96), as well as: anxious/depressed, functional impairment, memory, thought, and irritable/disinhibited problems on syndrome scales; depressive, somatic, and psychotic problems on Diagnostic and Statistical Manual of Mental Disorders scales; and adjustment problems in relationship satisfaction with spouse/partner. Maternal hypertension without proteinuria was not consistently associated with adjustment and problems (total problems, aOR 1.08, 95%CI 0.75-1.57; critical items, aOR 1.58, 95%CI 0.91-2.72). CONCLUSIONS: Maternal hypertensive disorders in pregnancy, during a period of expectant treatment, carry an increased risk of problems in adaptive functioning and mental wellbeing in the offspring seven decades later. Being the longest follow-up on transgenerational consequences of maternal hypertensive disorders reported thus far, our study points to the life-time increased risk of an adverse intrauterine environment.

Early life stress and blood pressure levels in late adulthood.

Severe stress experienced in early life may have long-term consequences on adult physiological functions. We studied the long-term effects of separation on blood pressure levels in non-obese subjects who were separated temporarily in childhood from their parents during World War II (WWII). The original clinical study cohort consists of people born during 1934-1944 in Helsinki, Finland. This substudy includes 1361 non-obese subjects (body mass index <30 kg m(-2)). Of these, 192 (14.1%) had been evacuated abroad during WWII. The remaining subjects served as controls. Blood pressure levels and use of blood pressure medication were studied. The separated subjects had significantly higher systolic blood pressure values than the non-separated (148.6+21.5 vs 142.2+19.6 mm Hg, P<0.0001) in adult life. Those subjects separated in early childhood had markedly higher systolic and diastolic blood pressure values in adult life compared with the non-separated (154.6 vs 142.5 mm Hg; 95% confidence interval (CI) 2.6-14.7; P<0.005 and 90.8 vs 87.7 mm Hg; 95% CI 1.0-7.3; P<0.02, respectively). Systolic blood pressure was also higher in the group separated for a duration of <1 year (151.7 vs 142.2 mm Hg; 95% CI 0.0-12.4; P<0.05) compared with the non-separated. Besides being separated, age at separation and duration of separation also influenced blood pressure levels in adult life. This could be due to early hormonal and metabolic programming, during plastic periods in early life, influencing blood pressure levels in adult life.

OS103. Hypertensive disorders during pregnancy and cognitive decline of the offspring up to old age: the helsinki birth cohort study.

INTRODUCTION: Hypertensive disorders affect the fetal developmental milieu and may point to mechanisms by which prenatal adversity is associated with lower cognitive ability in subsequent life. OBJECTIVES: We tested whether hypertensive disorders during pregnancy predict age-related change in cognitive ability in the offspring up to old age. METHODS: Using mothers' blood pressure and urinary protein measurements from the maternity clinics and birth hospitals, we defined normotensive or hypertensive pregnancies in mothers of 398 men, who participated in the Helsinki Birth Cohort 1934-44 Study. The men underwent the Finnish Defense Forces basic ability test twice, first, during compulsory military service at age 20.1 (SD=1.4) years and, then, in a re-test at age 68.5 (SD=2.9) years. The test yields a total score and subscores for tests measuring verbal, arithmetic and visuospatial reasoning. Scores were standardized with a mean of 100 and standard deviation of 15. RESULTS: Men born after pregnancies complicated by a hypertensive disorder, compared with men born after normotensive pregnancies, scored 3.84 (95% Confidence Interval, 0.77 to 6.91) points lower on total cognitive ability at 68.5 years, and displayed a greater decline in total cognitive ability (2.31, 0.23 to 4.39) after 20.1 years. Of the subscores, associations were strongest for arithmetic reasoning. CONCLUSION: Maternal hypertensive disorders in pregnancy predict lower cognitive ability and greater cognitive decline up to old age. Multidisciplinary research is essential in order to uncover the mechanisms linking hypertensive pregnancy disorders with lower cognitive abilities in the offspring.

Neurocognitive abilities in young adults with very low birth weight.

OBJECTIVE: Although severely preterm birth has been associated with impaired neurocognitive abilities in children, follow-up studies in adulthood are scarce. We set out to study whether adults born with very low birth weight (VLBW) (<1,500 g), either small for gestational age (SGA) (birth weight ≤-2 SD) or appropriate for gestational age (AGA), differ in a range of neurocognitive abilities and academic performance from adults born at term and not SGA. METHODS: As part of the Helsinki Study of Very Low Birth Weight Adults, 103 VLBW (37 SGA) and 105 term-born control adults (mean age 25.0, range 21.4-29.7 years) without major neurosensory impairments participated in the follow-up study in 2007-2008. The test battery included measures of general cognitive ability as well as executive functioning and related abilities. Academic performance was self-reported. RESULTS: With adjustment for sex and age, the VLBW group scored lower or performed slower than the control group in some indices of all tests (these mean differences ranged from 0.3 to 0.5 SD units, p ≤ 0.03) and they had received remedial education at school more frequently; however, no differences existed in self-reported academic performance. The differences were evident in both VLBW-SGA and VLBW-AGA groups. Further covariate adjustments for parental education, current head circumference, and head circumference at birth and, in tests of executive functioning and related abilities, adjustment for IQ estimate had minor effects on the results. CONCLUSIONS: In comparison with control adults, VLBW adults scored lower on several neurocognitive tests. Poorer neurocognitive performance is associated with VLBW irrespective of the intrauterine growth pattern.

Body size at birth and cardiovascular response to and recovery from mental stress in children.

Cardiovascular (CV) response to mental stress, a predictor of CV disease risk, may be determined already in utero. However, the underlying mechanisms remain unclear, and previous studies have used adult subjects and neglected CV recovery. We investigated 147 girls and 136 boys aged 8 years who underwent the Trier Social Stress Test for children to determine whether body size at birth is associated with CV activity. Blood pressure (BP), electrocardiogram and impedance-derived indices were recorded and analyzed from continuous measurements using Vasotrac APM205A and Biopac MP150 systems. Among girls, lower birth weight was associated with lower baseline systolic BP (SBP) and diastolic BP (DBP) values (1.9 mm Hg and 1.5 mm Hg per 1 s.d. birth weight for gestational age, respectively), higher SBP and DBP response to mental stress (1.6 mm Hg and 1.1 mm Hg per 1 s.d. birth weight for gestational age, respectively), slower BP recovery and overall higher cardiac sympathetic activity. In contrast, among boys lower birth weight was associated with higher baseline levels of SBP (2.1 mm Hg per 1 s.d. birth weight for gestational age) and total peripheral resistance (TPR), overall lower cardiac sympathetic activity, lower TPR response to mental stress and a more rapid BP and cardiac sympathetic recovery. In boys, the associations with baseline levels and cardiac sympathetic activity became significant only after adjusting for current body size. These sex-specific results suggest that individual differences in childhood CV response to and recovery from mental stress may have prenatal origins. This phenomenon may be important in linking smaller body size at birth to adult CV disease.

Depressive symptoms in adulthood and intrauterine exposure to pre-eclampsia: the Helsinki Birth Cohort Study.

OBJECTIVE: We studied whether pre-eclampsia predicts depressive symptoms in offspring. DESIGN: Retrospective longitudinal cohort study. SETTING: Participants in the Helsinki Birth Cohort 1934-44 Study. POPULATION: We classed 788 women and men born at term after a normotensive, hypertensive or pre-eclamptic pregnancy, by using the mother's blood pressure and urinary protein measurements, at maternity clinics and birth hospitals. METHODS: Linear and logistic regression analyses. We made adjustments for the mother's age and body mass index (BMI) at delivery, the participant's body size at birth/length of gestation, sex and childhood socio-economic status, age and educational attainment at testing. MAIN OUTCOME MEASURES: Beck depression inventory (BDI) scores completed twice, at the ages of 60 and 63 years. RESULT: Participants born after a primiparous pregnancy complicated by pre-eclampsia had over 30% (P < 0.04) higher depressive symptom scores in adulthood compared with those born after a primiparous normotensive pregnancy. We found no evidence of the association between pre-eclampsia and depression among participants born after multiparous pregnancies. Gestational hypertension and depressive symptoms were not significantly associated. The models adjusting for mother's age and BMI at delivery, the participant's body size at birth/length of gestation, sex, childhood socio-economic status, age and educational attainment at testing did not change the results. CONCLUSION: Pre-eclampsia is associated with later depressive symptoms in individuals born at term and after a primiparous pregnancy. These findings are compatible with the adverse fetal 'programming' by a suboptimal prenatal environment.

Romantic attachment in young adults with very low birth weight - The Helsinki Study of Very Low Birth Weight Adults.

Early attachment relationships from infancy onward contribute to attachment patterns later in life, to the ability to build up close relationships and to well-being in general. Severely preterm birth may challenge the development of these attachment relationships. We studied whether there are differences in attachment patterns related to romantic relationships between young adults (mean age 22.4 years, s.d. 2.2 years) with very low birth weight (VLBW, <1500 g; n = 162) and their peers born at term (n = 172), who completed the Experiences in Close Relationships Questionnaire - Revised. Young adults born at VLBW showed lower attachment-related anxiety than their peers born at term (mean difference -9.5%, 95% CI -16.0 to -2.6) when adjusted for sex, age, parental education and being in a romantic relationship currently. The groups did not differ in attachment-related avoidance. In subgroup analyses, the VLBW women born small for gestational age (SGA, birth weight <-2 s.d.) scored on average 14.8% (95% CI 3.1-26.6) higher than the control women on attachment avoidance. The effects remained after the exclusion of 18 participants with neurosensory deficits. We found no evidence for a compromised attachment pattern in young adults born at VLBW, with a possible exception of women born SGA at VLBW. VLBW adults were rather characterized by a lower level of attachment-related anxiety.

Prenatal growth, postnatal growth and trait anxiety in late adulthood - the Helsinki Birth Cohort Study.

OBJECTIVE: Trait anxiety may predispose to anxiety disorders and cardiovascular events. We tested whether prenatal growth or postnatal growth from birth to 11 years of age and in adulthood predict trait anxiety in late adulthood. METHOD: Women (n = 951) and men (n = 753) reported trait anxiety using the Spielberger Trait Anxiety Scale at an average age of 63.4 years and growth was estimated from records. RESULTS: Higher trait anxiety was predicted by smaller body size at birth, in infancy and in adulthood. Moreover, faster growth particularly from seven to 11 years of age and slower growth between 11 and 63 years predicted higher trait anxiety. CONCLUSION: We found a pattern of pre- and postnatal growth that predisposed to higher trait anxiety in late adulthood. This pattern resembles that found to increase the risk of cardiovascular events and, thus, points to a shared common origin in a suboptimal prenatal and childhood developmental milieu.

Childhood socioeconomic status modifies the association between intellectual abilities at age 20 and mortality in later life.

BACKGROUND: People who score poorly in intellectual ability tests have shorter life expectancy. A study was undertaken to determine whether this association is different in people from different socioeconomic backgrounds. METHODS: The mortality of 2786 men born in Helsinki, Finland during 1934-1944 who, as military conscripts, underwent a standardised intellectual ability test comprising verbal, visuospatial and arithmetic reasoning subtests was studied. Mortality data came from the Finnish Death Register. RESULTS: Comparing men in the lowest and highest test score quartiles, HRs for all-cause mortality were 1.9 (95% CI 1.4 to 2.5) for verbal reasoning, 2.2 (95% CI 1.6 to 3.0) for visuospatial reasoning and 1.9 (95% CI 1.4 to 2.5) for arithmetic reasoning, corresponding to 2.6, 3.4 and 2.6 excess years of life lost, respectively. Associations were similar for cardiovascular and non-cardiovascular mortality. Intellectual ability scores were stronger predictors in men who grew up in middle-class families. Compared with middle-class men in the highest quartile of the visuospatial reasoning score, middle-class men in the lowest quartile lost 6.5 years of life while men from families of manual workers in the highest quartile lost 2.8 years and men in the lowest quartile lost 5.6 years. CONCLUSIONS: High intellectual ability in men aged 20 protects them from mortality in later life. This effect is stronger in men who grew up in middle-class families than in those who grew up in manual worker families. This finding suggests that early life conditions that are unfavourable to the development of cognitive abilities negate the life expectancy benefits of being born into a more affluent family.

Efficacy of oral and parenteral ketoprofen in lactating cows with endotoxin-induced acute mastitis.

One hind quarter of 27 healthy lactating cows was infused with 100 microg Escherichia coli endotoxin. Two hours later, nine of the cows were given physiological saline by intramuscular injection, nine were given 4 mg/kg ketoprofen orally, and nine were given 3 mg/kg ketoprofen by intramuscular injection. Ketoprofen administered either orally or parenterally significantly reduced the effect of the endotoxin on rectal temperature, ruminal contractions and respiratory rate. The size of the udder, the signs of pain and the concentrations of thromboxane B2, especially in plasma, were also reduced, and the appearance of their milk was almost normal. The response of cows to the oral treatment was as rapid as it was to intramuscular treatment.

Neonatal ventilation with inhaled nitric oxide vs. ventilatory support without inhaled nitric oxide for infants with severe respiratory failure born at or near term: the INNOVO multicentre randomised controlled trial.

BACKGROUND: Evidence from European centres to support the use of nitric oxide (NO) in mature newborns with evidence of severe respiratory failure is sparse. METHODS: Infants of >33 weeks' gestation, <28 days old, and with severe respiratory failure requiring ventilatory support were randomised to receive or not to receive inhaled NO (iNO). The study was not blinded. RESULTS: Sixty infants were recruited (29 allocated iNO, 31 no iNO) from 15 neonatal units in the UK, Finland, Belgium and the Republic of Ireland. 15/60 recruited babies died, and 8.1% of the survivors (4/45) were classified as severely disabled at 1 year. There was no statistically significant difference between the randomised groups in terms of the primary outcome of death or severe disability by the corrected age of 1 year (relative risk = 0.96 (95% confidence interval = 0.46-2.03); p = 0.86) (Fisher's exact p = 1.00). The costs of NO were outweighed by reduced extra corporeal membrane oxygenation costs in the iNO group. The mean total hospitalisation costs were lower in the iNO group, although the mean difference (1,697 pounds) was not statistically significant (95% confidence interval = -14,472 to 11,478). CONCLUSIONS: The results complement those of previous studies that suggest NO is cost-effective and reduces the need for extra corporeal membrane oxygenation in this group of babies. Overall survival rates compare unfavourably with results of US trials.

Small body size at birth and behavioural symptoms of ADHD in children aged five to six years.

BACKGROUND: Behavioural disorders with a neurodevelopmental background, such as attention deficit hyperactivity disorder (ADHD), have been associated with a non-optimal foetal environment, reflected in small body size at birth. However, the evidence stems from highly selected groups with birth outcomes biased towards the extreme low end of the distribution in birth weight. Whether a similar association exists among the normal range of term birth is unclear. METHODS: The ADHD Rating Scale was filled in by the biological mothers and fathers of children aged five to six years who were born healthy at term. Information on weight (kg), height (cm), head circumference (cm), and gestational age at birth were obtained from hospital records, and the ponderal index (kg/m3), a commonly used measure of thinness, and head circumference-to-length ratio were calculated. RESULTS: Behavioural symptoms of ADHD were predicted by a lower ponderal index, a smaller head circumference, and a smaller head circumference-to-length ratio (beta's: -.12 to -.14, p's < .05). Adjustments for length of gestation, mother's age, tobacco and alcohol use during pregnancy, pre-pregnancy body mass index (BMI), or parity, the monthly gross income of the family, child's BMI at the age of five to six years or gender did not change the associations. CONCLUSION: These results suggest that physiological adaptation in utero, indicated by small body size at birth, within term gestational range may increase the susceptibility to behavioural symptoms of ADHD.

Effect of age and repeated hyperbaric oxygen treatments on vagal tone.

OBJECTIVES: To evaluate the influence of repeated hyperbaric oxygen (HBO2) exposures and age on vagal response to hyperbaric oxygenation, and to evaluate the timing of changes in vagal activity during the treatments. STUDY DESIGN: Open, controlled, non-randomized study. METHODS: Heart rate variability of 23 patients with chronic osteomyelitis or radionecrosis of the jaw or reconstructive surgery of the facial region was studied during repeated treatments. During each treatment, the patients were exposed to HBO2 at 2.5 ATA and heart rate variability was measured using power spectral analysis before compression, three times at 2.5 ATA and during and after decompression. The patients were grouped according to age (Cut-off point 50 years). Statistical analysis was carried out using analysis of variance for repeated measurements. RESULTS: Repeated exposures did not change vagal response to hyperbaric oxygenation. Vagal activity measured by HF power increased significantly in both age groups during the HBO2 exposures but there were no significant difference between the groups in the response. However, the level of HF power was significantly higher in the subjects under 50 years old. Significant differences between consecutive measurements were related to pressure changes. CONCLUSIONS: Repeated therapeutic HBO2exposures are not causing permanent changes in vagal control of the heart. Vagal responsiveness to hyperbaric hyperoxia is preserved in advanced age.