Torsten Tuvemo

Risk of High Blood Pressure Among Young Men Increases With the Degree of Immaturity at Birth

Background— Survivors of preterm birth constitute a new generation of young adults, but little is known about their long-term health. We investigated the association between gestational age (GA) and risk of high blood pressure (HBP) in young Swedish men and whether GA modified the risk of HBP; ie, whether HBP was related to being born small for gestational age (SGA). Methods and Results— This population-based cohort study included 329 495 Swedish men born in 1973 to 1981 who were conscripted for military service in 1993 to 2001. Multivariate linear- and logistic-regression analyses were performed. Main outcome measures were systolic and diastolic BPs at conscription. Linear-regression analyses showed that systolic BP increased with decreasing GA (regression coefficient −0.31 mm Hg/wk, P<0.001). Systolic and diastolic BPs both increased with decreasing birth weight for GA, but the association with systolic BP was most evident (regression coefficient −0.67 mm Hg per SD score in birth weight for GA, P<0.001). Compared with men born at term (GA, 37 to 41 weeks), the adjusted odd ratios (95% confidence intervals [CIs]) for high systolic BP (≥140 mm Hg) were as follows: moderately preterm (33 to 36 weeks), 1.25 (1.19 to 1.30); very preterm (29 to 32 weeks), 1.48 (1.30 to 1.68); and extremely preterm (24 to 28 weeks), 1.93 (1.34 to 2.76). Being SGA was associated only with an increased risk of high systolic BP among men born at 33 weeks or later. The risk estimates for high diastolic BP (≥90 mm Hg) increased with decreasing GA, but the risk reached significance only among men born moderately preterm. Conclusions— Preterm birth, a common pregnancy complication, is a risk factor for HBP in young men. The risk of high systolic BP associated with birth weight for GA is modified by GA, suggesting that perinatal contributions to BP elevation later in life may be induced by different biological pathways.

Thromboxane A2: Effects of airway and vascular smooth muscle

Thromboxane A2, an unstable compound derived from prostaglandin G2, was generated by incubation of arachidonic acid with a suspension of human platelets. The activity of thromboxane A2 relative to that of prostaglandin H2 in causing contractions of a number of smooth muscle organs were as follows: rabbit aorta, 7-20; human umbilical artery, 9-60; and guinea pig trachea, 2-12. Intravenous injection of thromboxane A2 into anaesthetized quinea pigs was followed by a pronounced increase in the tracheal insufflation pressure, potency compared to prostaglandin H2, 31-45.

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.

The Swedish childhood diabetes study — results from a nine year case register and a one year case-referent study indicating that Type 1 (insulin-dependent) diabetes mellitus is associated with both Type 2 (non-insulin-dependent) diabetes mellitus and autoimmune disorders

SummaryFrom July 1, 1977 to July 1, 1986, 3,503 incident cases of Type 1 (insulin-dependent) diabetes mellitus were registered in the Swedish childhood diabetes study. Using data from this register and from a case-referent study, including all incident Type 1 diabetic children in Sweden during one year and, for each patient, two referent children matched according to age, sex and county, we have studied the associations between Type 1 diabetes and familial Type 1 and Type 2 (non-insulin-dependent) diabetes, thyroid, adrenal, allergic, rheumatic, heart and bowel disease. The mean annual incidence per 100,000 during the nine year period was 25.1 for boys and 23.5 for girls. In 8.5% of the patients, one parent had Type 1 diabetes, 73% of whom were fathers. Fifty-six of the patients (1.7%) had a parent with Type 2 diabetes. The prevalence of parental Type 1 diabetes tended to be higher in patients with younger age at onset; whereas, the opposite was found for patients with parental Type 2 diabetes. In the case-referent study, the age-adjusted odds ratio for Type 1 diabetes when a first and/or second degree relative had Type 1 diabetes was 5.5 (95% confidence limits 4.0–7.7), and in accordance with the findings of the case register, the odds ratio tended to be highest in patients with the youngest age at onset. Season at onset of the patients was not associated with parental Type 1 diabetes. The odds ratio for Type 1 diabetes was significantly increased 3.3 (95% confidence limits: 2.3–4.6) when Type 2 diabetes was reported in relatives (three generations). Odds ratios were also significantly increased (p(0.05) when thyroid or rheumatic diseases were reported among relatives.It is concluded that although the majority of incident Type 1 diabetic children lack family history, parental Type 1 diabetes may influence the age at onset of the disease but has no effect on sex distribution of these children. An increased risk for Type 1 diabetes in children is also indicated when Type 2 diabetes, (non-insulin-treated) thyroid or rheumatic disease is reported in relatives.

Menarcheal age and growth pattern of Indian girls adopted in Sweden. I. Menarcheal age.

ABSTRACT. The median menarcheal age of 107 girls adopted from India by families in Sweden was 11.6 years, which was significantly lower than in Swedish and most Indian studies. Five girls had menarche before the age of 9 years, the earliest at 7.3 years. Those who arrived at a later age had earlier menarche. No differences in menarcheal age were found with respect to geographic origin. The reasons for the earlier pubertal maturation are not clear. Factors associated with the rapid transition from an underprivileged to a privileged environment are probably involved, besides genetic determinants. The serious medical, social and emotional consequences of very early pubertal development necessitate further clarification of the underlying mechanisms.

Dose-Dependent Effect of Growth Hormone on Final Height in Children with Short Stature without Growth Hormone Deficiency

CONTEXT The effect of GH therapy in short non-GH-deficient children, especially those with idiopathic short stature (ISS), has not been clearly established owing to the lack of controlled trials continuing until final height (FH). OBJECTIVE The aim of the study was to investigate the effect on growth to FH of two GH doses given to short children, mainly with ISS, compared with untreated controls. DESIGN AND SETTING A randomized, controlled, long-term multicenter trial was conducted in Sweden. INTERVENTION Two doses of GH (Genotropin) were administered, 33 or 67 microg/kg.d; control subjects were untreated. SUBJECTS A total of 177 subjects with short stature were enrolled. Of these, 151 were included in the intent to treat (AllITT) population, and 108 in the per protocol (AllPP) population. Analysis of ISS subjects included 126 children in the ITT (ISSITT) population and 68 subjects in the PP (ISSPP) population. MAIN OUTCOME MEASURES We measured FH sd score (SDS), difference in SDS to midparenteral height (diff MPHSDS), and gain in heightSDS. RESULTS After 5.9+/-1.1 yr on GH therapy, the FHSDS in the AllPP population treated with GH vs. controls was -1.5+/-0.81 (33 microg/kg.d, -1.7+/-0.70; and 67 microg/kg.d, -1.4+/-0.86; P<0.032), vs. -2.4+/-0.85 (P<0.001); the diff MPHSDS was -0.2+/-1.0 vs. -1.0+/-0.74 (P<0.001); and the gain in heightSDS was 1.3+/-0.78 vs. 0.2+/-0.69 (P<0.001). GH therapy was safe and had no impact on time to onset of puberty. A dose-response relationship identified after 1 yr remained to FH for all growth outcome variables in all four populations. CONCLUSION GH treatment significantly increased FH in ISS children in a dose-dependent manner, with a mean gain of 1.3 SDS (8 cm) and a broad range of response from no gain to 3 SDS compared to a mean gain of 0.2 SDS in the untreated controls.

Coxsackie B virus IgM in children at onset of type 1 (insulin-dependent) diabetes mellitus: evidence for IgM induction by a recent or current infection.

SummaryThirty-five children with newly-diagnosed Type 1 (insulin-dependent) diabetes mellitus and their 47 siblings were investigated for the presence of IgM antibodies to Coxsackie B virus serotypes 1–5 (CBV1-5) with the aid of μ-antibody-capture radioimmunoassays. When a high cut-off value was used, 16 (46%) diabetic children and 16 (34%) siblings showed CBV-IgM. Of the siblings of diabetic patients positive for CBV-IgM, 11 (44%) were CBV-IgM-positive; the corresponding figure for the siblings of negative patients was five (26%). With a lower cut-off value, leading to a “borderline titre”, the frequency of IgM positivity increased in both the patients and siblings. When the borderline titres were included, the number of IgM-positive patients was 19 (54%) and the corresponding number of siblings was 29 (62%). Of the siblings of positive patients, 27 (93 %) showed CBV-IgM, and of the siblings of the negative patients, two (11 %) were CBV-IgM-positive. Sixteen (89 %) siblings of IgM-negative patients remained negative. Regarding the serotypes of CB V to which IgM was directed, CBV 4 was most frequent, followed by serotypes CBV 3, CBV 2, CBV 5 and CBV 1. There was a striking similarity between the individual diabetic child and his or her sibling(s) concerning this specificity of IgM. It is concluded that within most families with a newly-diagnosed diabetic child positive for CBV-IgM the same serotype(s) of the virus circulates and that the intrafamilial spread of virus is considerable. The results strongly indicate that the IgM detected was CBV-specific and caused by a recent or current CBV infection. It is highly probable that the same strain of virus was present in different members of the same family. Therefore, if diabetogenic CBV strains do in fact exist, additional factors must be of importance for the development of Type 1 diabetes in children infected with such a CBV strain but remaining non-diabetic.

Menarcheal age and growth pattern of Indian girls adopted in Sweden. II. Catch-up growth and final height

Adopted girls (n=107) previously studied regarding menarcheal age in relation to age at arrival, were analysed as to growth pattern and final height related to nutritional status at arrival and menarcheal age. It was found that most girls had catch-up growth regarding height and half of them regarding weight. Faster catch-up and later arrival age in Sweden were associated with earlier menarche. The catch-up growth was, however, incomplete, and lower the initial height for age, lower was the height for age at the succeeding measurements, and the final height. The mean final height was 154 cm, but 8% of the girls were 145 cm or shorter. The data suggest that linear growth and final height is influenced by the preadoptive nutritional condition, as well as by the degree and timing of subsequent catch-up growth, and the timing of puberty. Pubertal onset is related to the degree and timing of catch-up growth.

The possible role of Coxsackie A and echo viruses in the pathogenesis of type I diabetes mellitus studied by IgM analysis

IgM antibodies to Coxsackie B virus (CBV) have recently been observed in the serum of a relatively high proportion of children with newly diagnosed insulin-dependent diabetes mellitus (IDDM). In the present study, 108 IDDM patients below the age of 15 years, diagnosed during the period 1976 to 1985, were investigated at the onset of their disease by mu-antibody-capture radioimmunoassay (RIA) of IgM against seven different enterovirus antigens, namely virions of CBV serotypes 1-5 (CBV 1-5) and procapsids of CBV 3 and CBV 5. As has been shown the RIAs with virions give type-specific or narrow type-specific reactions, whereas procapsids react with IgM against both homotypic and heterotypic enteroviruses. The annual frequency of IgM against virions varied between 15 and 76% (mean 38%). IgM against CBV3 and CBV2 predominated, but IgM against the other serotypes was also observed. When procapsids were used as antigen, the frequency of IgM varied between 11 and 86% (mean 63%). With virions and procapsids, the corresponding variation was 44-100% (mean 70%). The total number of patients exhibiting virion-IgM was 41, whereas procapsid-IgM alone [indicating an infection with Coxsackie A virus (CAV) and/or echo virus (EV)] was detected in 36 patients. For 2 of the years, samples of serum from control groups were included. These showed a significantly lower frequency of IgM in both the virion and the procapsid RIAs. It is concluded that not only infection with CBV but also that with other enteroviruses, such as CAV and/or EV, may be involved in the pathogenesis of IDDM in children.

Growth Hormone (GH) Dosing during Catch-Up Growth Guided by Individual Responsiveness Decreases Growth Response Variability in Prepubertal Children with GH Deficiency or Idiopathic Short Stature

CONTEXT Weight-based GH dosing results in a wide variation in growth response in children with GH deficiency (GHD) or idiopathic short stature (ISS). OBJECTIVE The hypothesis tested was whether individualized GH doses, based on variation in GH responsiveness estimated by a prediction model, reduced variability in growth response around a set height target compared with a standardized weight-based dose. SETTING A total of 153 short prepubertal children diagnosed with isolated GHD or ISS (n = 43) and at least 1 SD score (SDS) below midparental height SDS (MPH(SDS)) were included in this 2-yr multicenter study. INTERVENTION The children were randomized to either a standard (43 microg/kg.d) or individualized (17-100 microg/kg.d) GH dose. MAIN OUTCOME MEASURE We measured the deviation of height(SDS) from individual MPH(SDS) (diffMPH(SDS)). The primary endpoint was the difference in the range of diffMPH(SDS) between the two groups. RESULTS The diffMPH(SDS) range was reduced by 32% in the individualized-dose group relative to the standard-dose group (P < 0.003), whereas the mean diffMPH(SDS) was equal: -0.42 +/- 0.46 and -0.48 +/- 0.67, respectively. Gain in height(SDS) 0-2 yr was equal for the GH-deficient and ISS groups: 1.31 +/- 0.47 and 1.36 +/- 0.47, respectively, when ISS was classified on the basis of maximum GH peak on the arginine-insulin tolerance test or 24-h profile. CONCLUSION Individualized GH doses during catch-up growth significantly reduce the proportion of unexpectedly good and poor responders around a predefined individual growth target and result in equal growth responses in children with GHD and ISS.