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Marianne Andersen

Publications and source records attributed to Marianne Andersen.

At least 19 recordsLinked to original sources
PubMed2026

Genomic analyses implicate hormonal and metabolic dysregulation in polycystic ovary syndrome.

Polycystic ovary syndrome (PCOS) and its underlying features remain poorly understood. In this genetic study (n = 544,513), we expand the number of genetic loci from 16 to 29, and additionally identify 31 associated plasma proteins. Many risk-increasing loci were associated with later age at menopause, underscoring the reproductive longevity related to an increased oocyte number and/or availability across the lifespan. Hormonal regulation in the etiology of this condition, through metabolic and reproductive features, was emphasized. The proteomic analysis highlighted metabolic biology known to be related to PCOS. A polygenic risk score (PRS) was associated with adverse cardiometabolic outcomes, with differing relevance of testosterone and body mass index in women and men. Finally, while oligo-anovulation and anovulatory infertility are features of PCOS, we observed no impact of PCOS susceptibility on childlessness. We suggest that PCOS susceptibility confers balanced pleiotropic influences on fertility in women, and life-long adverse metabolic consequences in both sexes.

Humans↗
PubMed2006

Suppression of testosterone does not blunt mRNA expression of myoD, myogenin, IGF, myostatin or androgen receptor post strength training in humans.

We hypothesized that suppression of endogenous testosterone blunts mRNA expression post strength training (ST). Twenty-two young men were randomized for treatment with the GnRH analogue goserelin (3.6 mg every 4 weeks) or placebo for a period of 12 weeks. The ST period of 8 weeks started at week 4. Strength test, blood sampling, muscle biopsies, and whole-body dual-energy X-ray absorptiometry (DXA) scan were performed at weeks 4 and 12. Muscle biopsies were taken during the final ST session (pre, post 4 h, and post 24 h). Resting serum testosterone decreased significantly (P < 0.01) in the goserelin group from 22.6 +/- 1.6 (mean +/- s.e.m.) to 2.0 +/- 0.1 nmol l(-1) (week 4), whereas it remained unchanged in the placebo group. An acute increase of serum testosterone was observed during the final ST session in the placebo group (P < 0.05), whereas a decreased response was observed in the goserelin group (P < 0.05). mRNA expression of IGF-IE(bc) and myogenin increased, while expression of myostatin decreased (P < 0.01); however, no differences were observed between the groups. Muscle strength and muscle mass showed a tendency to increase more in the placebo group than in the goserelin group (P = 0.05). In conclusion, despite blocked acute responses of testosterone and 10- to 20-fold lower resting levels in the goserelin group, ST resulted in a similar mRNA expression of myoD, myogenin, IGF-IE(abc), myostatin and androgen receptor as observed in the placebo group. Therefore, in the present study, the molecular events were the same, despite divergent muscle hypertrophy and strength gains.

Adult↗
PubMed2006

Suppression of endogenous testosterone production attenuates the response to strength training: a randomized, placebo-controlled, and blinded intervention study.

We hypothesized that suppression of endogenous testosterone would inhibit the adaptations to strength training in otherwise healthy men. Twenty-two young men with minor experience with strength training participated in this randomized, placebo-controlled, double-blinded intervention study. The subjects were randomized to treatment with the GnRH analog goserelin (3.6 mg) or placebo (saline) subcutaneously every 4 wk for 12 wk. The strength training period of 8 wk, starting at week 4, included exercises for all major muscles [3-4 sets per exercise x 6-10 repetitions with corresponding 6- to 10-repetition maximum (RM) loads, 3/wk]. A strength test, blood sampling, and whole body DEXA scan were performed at weeks 4 and 12. Endogenous testosterone decreased significantly (P < 0.01) in the goserelin group from 22.6 +/- 5.5 (mean +/- SD) nmol/l to 2.0 +/- 0.5 (week 4) and 1.1 +/- 0.6 nmol/l (week 12), whereas it remained constant in the placebo group. The goserelin group showed no changes in isometric knee extension strength after training, whereas the placebo group increased from 240.2 +/- 41.3 to 264.1 +/- 35.3 Nm (P < 0.05 within and P = 0.05 between groups). Lean mass of the legs increased 0.37 +/- 0.13 and 0.57 +/- 0.30 kg in the goserelin and placebo groups, respectively (P < 0.05 within and P = 0.05 between groups). Body fat mass increased 1.4 +/- 1.0 kg and decreased 0.6 +/- 1.2 kg in the goserelin and placebo groups, respectively (P < 0.05 within and between groups). We conclude that endogenous testosterone is of paramount importance to the adaptation to strength training.

Absorptiometry, Photon↗
PubMed2006

Effect of pioglitazone on glucose metabolism and luteinizing hormone secretion in women with polycystic ovary syndrome.

OBJECTIVE: To thoroughly examine the mechanisms for insulin resistance in polycystic ovary syndrome (PCOS) and to evaluate the effects of pioglitazone treatment on insulin resistance, beta-cell function, LH secretion, and glucose metabolism. DESIGN: Randomized, blinded, placebo-controlled study. SETTING: Outpatient clinic, at a university hospital in Denmark. PATIENT(S): Thirty obese women with PCOS and 14 weight-matched healthy females. INTERVENTION(S): Sixteen weeks of blinded treatment with pioglitazone (30 mg/d) or placebo. MAIN OUTCOME MEASURE(S): Fasting blood samples, 24-hour 20-minute integrated blood sampling (LH, insulin, and C-peptide), euglycemic hyperinsulinemic clamps including 3-(3)H glucose, and indirect calorimetry were performed before and after the intervention period. RESULT(S): Patients with PCOS had significantly lower insulin sensitivity compared with controls, including significantly decreased insulin-stimulated oxidative and nonoxidative glucose metabolism. Pioglitazone treatment resulted in significantly lower levels of fasting insulin and significantly higher insulin sensitivity, increased insulin-stimulated glucose oxidation, and increased insulin-stimulated inhibition of lipid oxidation. During 24-hour blood sampling, significantly lower area under-the-curve insulin and lower median insulin levels were observed. Secretion profiles of LH and E(2) and T levels did not change significantly. CONCLUSION(S): Insulin resistance in PCOS was characterized by hyperinsulinemia, impaired insulin-stimulated oxidative and nonoxidative glucose metabolism, which was partly reversed by pioglitazone treatment.

Adult↗
PubMed2006

Incidence of GH deficiency - a nationwide study.

OBJECTIVE: Data on incidence rates are scarce in GH deficiency (GHD). Here, we estimate the incidence rate in childhood onset (CO) and adult onset (AO) GHD in Denmark. DESIGN: We used three national registries to identify 9131 cases with an increased risk of GHD. Date of entry was defined using the date when a registration had taken place and when a date of sufficient information could be defined from a thorough examination of a record of a GHD patient, which ever came last. We considered date of entry as the incident date. METHODS: Sex-specific incidence rates of GHD in children and adults using the background population as reference. RESULTS: During 1980-1999, 1823 patients were incident. Three-hundred and three males and 191 females had CO, 744 males and 585 females had AO GHD. The incidence rate over time was stable for females with AO GHD and increasing for the other three subgroups. Average incidence rate for CO males, 2.58 (95% confidence interval (CI), 2.30-2.88), CO females, 1.70 (95% CI, 1.48-1.96), AO males, 1.90 (95% CI, 1.77-2.04), and AO females, 1.42 (95% CI, 1.31-1.54) all per 100 000. The incidence rate was significantly higher in males compared to females in the CO GHD group (P < 0.001) and in the AO GHD group in the age ranges of 45-64 and 65+years (P < 0.001). There was no significant difference in the 18-44 years age group. CONCLUSIONS: In conclusion, we have identified the incidence rates of GHD in a nationwide study of Denmark. In this population-based study, we have identified in CO GHD and in the two oldest age groups of AO GHD, a statistically significant higher incidence rate in males when compared with females.

Adolescent↗
PubMed2006

Evaluation of metabolic risk markers in polycystic ovary syndrome (PCOS). Adiponectin, ghrelin, leptin and body composition in hirsute PCOS patients and controls.

OBJECTIVE: Polycystic ovary syndrome (PCOS) patients are abdominally obese and are at increased risk of developing the metabolic syndrome. Low adiponectin and ghrelin levels in PCOS patients could be caused by insulin resistance as well as high testosterone levels. DESIGN: Adiponectin and ghrelin levels were evaluated in 51 hirsute PCOS patients referred to the outpatient clinic of an academic, tertiary care medical centre and in 63 weight-matched female controls. Relationships between adiponectin, ghrelin, leptin, body composition, testosterone and insulin were examined. METHODS: Measurements of body composition including waist-hip-ratio (WHR), body mass index (BMI) and whole body dual-energy X-ray absorptiometry scan measures of body fat mass. Measurements of fasting levels of adiponectin, ghrelin, leptin, androgen status, oestradiol, lipid variables and insulin during follicular phase. RESULTS: Adiponectin levels were significantly decreased in obese PCOS patients compared with weight-matched controls (geometric mean (-2 to 2 s.d.) 5.3 (2.5-11.1) vs 7.3 (3.0-17.4) mg/l, P<0.05). Mean ghrelin was significantly lower in hirsute PCOS patients than in controls (0.6 (0.3 to 1.4) vs 0.8 (0.4 to 1.7) microg/l, P<0.001) and this remained significant after subdividing subjects according to waist circumference and BMI. During multiple regression analysis, testosterone correlated positively with adiponectin and negatively with ghrelin independent of BMI, WHR and total fat mass. CONCLUSION: Obese hirsute PCOS patients demonstrated significantly lower adiponectin levels than weight-matched controls suggesting a very high risk for the metabolic syndrome. Furthermore, ghrelin levels were decreased in hirsute PCOS patients and showed a significant, negative correlation with testosterone independent of body composition.

Absorptiometry, Photon↗
PubMed2005

MTHFR c.677C>T polymorphism as an independent predictor of peak bone mass in Danish men--results from the Odense Androgen Study.

The MTHFR c.677C>T polymorphism has been shown to have significant effects on skeletal health in middle-aged to elderly women and men. Despite an accumulating amount of data on MTHFR genetics and the association between homocysteine levels and fracture, it remains unknown if MTHFR c.677C>T genotype affects bone mineral accretion in youth or bone loss in adulthood. The purpose of this cross-sectional study was to examine the effects of this common allelic polymorphism on peak bone mass and bone turnover. We performed MTHFR genotyping in 780 healthy Danish men, aged 20 to 29 years, participating in the Odense Androgen Study. BMD at the spine, hip and whole-body was measured using a Hologic QDR-4500 densitometer. Genotype frequencies were compatible with Hardy-Weinberg equilibrium. Spine BMD was significantly associated with genotype, with a decrease in BMD of 0.20 SD for each copy of the T-allele. Effects were independent of age, BMI, smoking and serum levels of vitamin D and IGF-I. Associations with BMD of the hip and whole body were short of statistical significance. MTHFR genotype showed no association with the bone turnover markers 1-CTP, bone specific alkaline phosphatase or osteocalcin. In conclusion, significant skeletal effects of this common polymorphism were present at the lumbar spine in men at the age of 25 years.

Absorptiometry, Photon↗
PubMed2005

Pioglitazone treatment increases spontaneous growth hormone (GH) secretion and stimulated GH levels in polycystic ovary syndrome.

BACKGROUND: Low GH levels, probably due to insulin resistance and increased abdominal fat mass, are well described in polycystic ovary syndrome (PCOS). GH acts as an important ovarian cogonadotropin, and GH disturbances may be an additional pathogenic factor in PCOS. Decreased abdominal fat mass and improved insulin sensitivity during pioglitazone treatment may affect GH secretion. OBJECTIVE: The objective of the study was to investigate the effect of pioglitazone on GH levels in PCOS. DESIGN: Thirty insulin-resistant PCOS patients were randomized to either 16 wk pioglitazone (30 mg/d) or placebo treatment. Before and after intervention, levels of fasting insulin, GH, total IGF-I, free IGF-I, IGF binding protein-1, IGF-II, free fatty acids, testosterone, and SHBG were measured. Patients underwent whole-body dual x-ray absorptiometry scans, pyridostigmine-GHRH tests, and 24-h 20-min integrated blood sampling for measurement of GH. RESULTS: Peak GH and area under the curve for GH in pyridostigmine-GHRH tests and 24-h mean GH concentrations and pulsatile GH secretion significantly increased after pioglitazone treatment. No significant changes were observed in GH pulse frequency, pulse duration, approximate entropy levels, or basal GH release. Levels of IGF binding protein-1 significantly increased, whereas no significant differences were measured in total IGF-I and free IGF-I. Pioglitazone treatment significantly decreased fasting insulin and homeostasis model assessment levels. No significant changes were observed in Ferriman Gallwey score or androgen levels. CONCLUSION: Pioglitazone treatment significantly increased GHRH-stimulated GH levels and 24-h pulsatile GH secretion, probably directly or indirectly due to improved insulin sensitivity.

Absorptiometry, Photon↗
PubMed2005

Higher bone mineral density in Caucasian, hirsute patients of reproductive age. Positive correlation of testosterone levels with bone mineral density in hirsutism.

OBJECTIVE: The mechanisms leading to higher bone mineral density (BMD) in hirsute patients than in healthy controls have seldom been examined. We compared the metabolic, hormonal and bone metabolic parameters in hirsute patients and female controls and correlated BMD and bone metabolic parameters with testosterone, oestradiol and metabolic parameters. PATIENTS: Fifty-one Caucasian, reproductive-aged, hirsute patients referred to the outpatient clinic of an academic tertiary-care medical centre and 63 healthy, female Caucasian controls matched for season, weight and age. MEASUREMENTS: BMD (hip, neck, lumbar and total BMD), bone metabolic parameters (osteocalcin, alkaline phosphatase, PTH, ionized calcium, phosphate and 25-hydroxyvitamin D (25OHD)) and endocrine profiles (androgen status, oestradiol and insulin) were evaluated during follicular phase. Oestradiol measurement was repeated during cycle days 8-12. RESULTS: Lumbar and neck BMD levels were significantly higher in hirsute patients than in controls: (mean +/- SD): lumbar BMD 1.10 +/- 0.12 vs. 1.06 +/- 0.10 g/cm2 and neck BMD 0.91 +/- 0.11 vs. 0.87 +/- 0.12 g/cm2, P < 0.05. Fasting insulin and free testosterone levels were significantly higher in hirsute patients than in controls. Free testosterone correlated positively with neck and hip BMD levels in hirsute patients. During multiple regression analysis, testosterone, oestradiol and waist/hip ratio (WHR) were found to have positive effects on BMD levels independent of body mass index (BMI). 25OHD levels were significantly lower in hirsute patients [42 (13-131)] than in controls [72 (27-196)] nmol/l (geometric mean +/- 2SD), P < 0.001]. CONCLUSION: Hirsute patients demonstrated significantly higher bone mineral density levels than controls, which could be explained by hyperinsulinaemia and higher testosterone levels in hirsute patients compared with controls. The pathogenesis for significantly lower 25-hydroxyvitamin D levels in hirsute patients compared with controls needs to be evaluated in future studies.

Adult↗
PubMed2005

Very short term dehydroepiandrosterone treatment in female adrenal failure: impact on carbohydrate, lipid and protein metabolism.

OBJECTIVE: In female adrenal insufficiency, dehydroepiandrosterone (DHEA) secretion is impaired and circulating androgen levels are severely reduced. We wanted to analyse the acute effects of physiological DHEA substitution on substrate metabolism. DESIGN: We studied nine females with adrenal insufficiency after 9 days of oral DHEA replacement (50 mg/day) in a double-blind, placebo-controlled crossover study. METHODS: Whole body and regional substrate metabolism was assayed in the basal state and during a euglycemic hyperinsulinemic glucose clamp by means of isotope dilution techniques (glucose, phenylalanine, tyrosine), indirect calorimetry and in situ lipolysis (microdialysis technique). RESULTS: DHEA treatment normalized the levels of all androgens. Basal and insulin-stimulated total energy expenditure and rates of protein, lipid and glucose oxidation were unaffected by DHEA. Whole body turnover of glucose and protein were also unaffected by DHEA. Forearm breakdown of protein was reduced by insulin to the same extent after placebo and DHEA. Insulin sensitivity as expressed by the glucose infusion rate during the euglycemic clamp was similar after placebo and DHEA. Finally, the interstitial release of glycerol in adipose tissue was not significantly influenced by DHEA. CONCLUSIONS: Short-term oral DHEA replacement in women with adrenal insufficiency was not associated with measurable changes in total or regional substrate metabolism.

Adrenal Insufficiency↗
PubMed2005

Discontinuation of estrogen replacement therapy in GH-treated hypopituitary women alters androgen status and IGF-I.

OBJECTIVE AND DESIGN: Compared with their male counterparts, healthy females secrete more growth hormone (GH) and those with GH-deficiency have lower insulin-like growth factor I (IGF-I) levels and are less responsive to GH substitution. To test whether this gender difference is related to sex hormones we measured androgen status and IGF-I related parameters in 38 hypopituitary women (mean (range) age 41.5 (20-58) years) during continued GH substitution as compared with a control group of 38 healthy women matched for age and menopausal status. Twenty six patients were studied twice: with estrogen replacement and after 28 days of estrogen discontinuation in a randomised design. RESULTS: The patients were androgen deficient compared with controls (median, range), dehydroepiandrosterone sulphate (DHEAS): 185 (99-7800) nmol/l vs 4400 (820-13,000) nmol/l, P=or<0.001; androstenedione: 0.5 (0.1-7.1) nmol/l vs 4.3 (1.6-8.8) nmol/l, P=or<0.001; dihydrotestosterone (DHT): 0.13 (0.09-0.54) nmol/l vs 0.55 (0.09-0.89) nmol/l, P=or<0.001; testosterone: 0.28 (0.09-1.56) nmol/l vs 1.1 (0.71-2.24) nmol/l, (P=or<0.001); free testosterone: 0.004 (0.001-0.030) nmol/l vs 0.016 (0.001-0.030) nmol/l, P=or<0.001. The circulating levels of IGF-I, IGF-II, IGF-binding protein 1 (IGFBP-1), and IGFBP-3 did not differ between patients and controls. The subgroup of patients receiving hydrocortisone (HC) replacement (n=24) had significantly lower levels of androgens (suppressed by 80-100%) as well as IGF-I and IGFBP-3 as compared with the patients not receiving HC. IGF-I was correlated to free testosterone in patients (r=0.57, P=0.0005) as well as controls (r=0.43, P=0.008), and free testosterone was a significant positive predictor of IGF-I. Estrogen discontinuation induced an increase in IGF-I (167+/-15 vs 206+/-14 microg/l, P=0.005 and IGFBP-3 (3887+/-139 vs 4309+/-138 microg/l, P=0.0005). Estrogen discontinuation was associated with a significant increase in median (range) free testosterone (0.004 (0-0.02) vs 0.0065 (0-0.03) nmol/l, P=0.001) and a significant decrease in median (range) sex-hormone binding globulin (SHBG; 93 (11-278) vs 55.5 (20-142) nmol/l, P=0.001). DeltaIGF-I correlated with DeltaSHBG (r=-0.45 P=0.033) and DeltaIGFBP-3 (r=0.67 P=or<0.001). In a regression model DeltaE2, Deltatestosterone, DeltaSHBG and DeltaIGFBP-3 explained 93% of the variation in DeltaIGF-I. CONCLUSIONS: Androgen levels are low in hypopituitary women and free testosterone correlates with IGF-I. Discontinuation of estrogen replacement in these patients induces elevations in IGF-I as well as free testosterone, and DeltaIGF-I correlated positively with Deltafree testosterone. These effects may contribute to the gender differences observed in the GH-IGF axis in healthy adults as well as in the responsiveness of hypopituitary patients to GH substitution.

Adult↗
PubMed2004

[Changes in reporting on passive smoking by parents of small children].

BACKGROUND: The Norwegian Cancer Society has led a comprehensive information campaign since 1995 with the aim of reducing young children's ETS (environmental tobacco smoke) exposure in their homes. The aims of the present study were to assess changes in parents' reporting of child exposure to ETS, attitudes towards ETS, and awareness regarding the potential hazards of passive smoking to children. MATERIAL AND METHODS: A questionnaire along with a stamped, addressed envelope was sent to a stratified random sample of 1000 households in Norway with three-year-old children at the time of the investigation (May 1995 and August 2001). RESULTS: According to parents, the prevalence of households in which children were exposed to ETS fell from 32% in 1995 to 18% in 2001. In both surveys, the probability of children being exposed was positively correlated with the number of parents smoking and inversely correlated with length of education, negative attitudes towards ETS and strength of health-risk awareness. INTERPRETATION: The observed changes must be viewed in the light of the media focus on passive smoking during this period, a nationwide information campaign and as an artifact caused by more underreporting of a behaviour that is being internalised as in breach of a norm.

Adult↗
PubMed2004

Prevalence of endocrine diseases and abnormal glucose tolerance tests in 340 Caucasian premenopausal women with hirsutism as the referral diagnosis.

OBJECTIVE: To perform an audit on the examination of hirsute patients and to establish a rational routine examination program in an outpatient endocrine clinic. DESIGN: Systematic, retrospective audit. SETTING: Academic tertiary-care medical center. PATIENT(S): Three hundred forty women with hirsutism as the referral diagnosis. INTERVENTION(S): Hormone analyses and ACTH tests during cycle days 2-8, 2 hours of oral glucose tolerance test (OGTT), and vaginal ultrasound. MAIN OUTCOME MEASURE(S): End diagnosis, fasting, 30-, 60-, and 120-minute oral glucose-stimulated levels of insulin and capillary blood glucose. RESULT(S): Two hundred one patients were diagnosed as having idiopathic hirsutism (IH) and 134 as having polycystic ovary syndrome (PCOS). End diagnosis: prolactinoma: n = 1, Cushing's syndrome: n = 1, androgen-producing ovarian tumor: n = 1, late-onset 21-hydroxylase defects: n = 2. During OGTT, 4.9% (13 of 263) had previously undiagnosed diabetes; no significant difference in diabetes prevalence was found between idiopathic hirsutism and PCOS. For 50.8%, fasting insulin values were in the upper quartile for a reference population. CONCLUSION(S): Initial evaluation of hirsute patients with irregular menses should include serum (s)-17alpha-hydroxyprogesterone, s-prolactin, s-Testosterone (T), and s-sex hormone-binding globulin. Further evaluation is needed in patients with markedly elevated s-T or with clinical Cushing's syndrome. Hirsute patients have a high risk of diabetes, although this could be due to the high number of overweight patients among this population.

Adrenal Hyperplasia, Congenital↗
PubMed2004

Dehydroepiandrosterone supplementation in women with adrenal failure: impact on twenty-four hour GH secretion and IGF-related parameters.

OBJECTIVE: In women, GH secretion is strongly influenced by oestrogen status, whereas the role of androgens is unclear. We, therefore, examined GH secretory dynamics during low vs. normalized androgen levels in women with adrenal failure. PATIENTS: Ten females with adrenal failure (AF), mean age of 42 years (range 22-54 years). DESIGN: The effects of 8 days of oral dehydroepiandrosterone (DHEA; 50 mg/day) were studied in a double-blind placebo-controlled, cross-over design. A control group of healthy women was studied once without any treatment. MEASUREMENTS: Before and after each treatment period, blood was sampled for measurement of androgens, IGF-I, IGFBP-3 and GHBP. A 24-h GH profile with measurements every 20 min was performed at the end of each period. RESULTS: DHEA supplementation normalized the mean circulating levels of testosterone and androgen precursors. The secretory pattern of GH was unaltered during DHEA [placebo vs. DHEA; half-life 22.83 +/- 1.24 vs. 21.45 +/- 1.19 (min), P = 0.429; pulse frequency 9.9 +/- 0.7 vs. 10.5 +/- 0.5 (/24 h), P = 0.502; total production rate 62.27 +/- 13.44 vs. 52.61 +/- 7.06 (microg/l/day), P = 0.317]. Subgroup analysis, however, indicated that DHEA treatment increased GH secretion in patients not receiving oestrogen (n = 5), whereas the opposite was observed among patients receiving exogenous oestrogen derivatives (n = 5). Compared to the control group (CON), GH half-life was longer in AF (half-life CON: 16.48 +/- 0.91, P = 0.001). The additional features of GH secretion were similar. Unexpectedly, the levels of IGF-I, IGFBP-3 and GHBP were elevated in the patients as compared to controls, without significant effects of DHEA [AF vs. CON. IGF-I: 186 +/- 20 vs. 144 +/- 7 (microg/l), P = 0.04; IGFBP-3: 5196 +/- 224 vs. 3687 +/- 212 (microg/l), P = 0.001; GHBP: 2.27 +/- 0.25 vs. 1.41 +/- 0.13 (nmol/l), P = 0.002]. CONCLUSION: (1) Short-term DHEA administration in women with adrenal failure normalizes the circulating levels of androgens without uniformly affecting the GH-IGF axis; (2) The observation that exogenous oestradiol may mask a stimulatory effect of DHEA on GH secretion merits future investigation.

Adrenal Insufficiency↗
PubMed2004

Graphical interpretation of confidence curves in rankit plots.

A well-known transformation from the bell-shaped Gaussian (normal) curve to a straight line in the rankit plot is investigated, and a tool for evaluation of the distribution of reference groups is presented. It is based on the confidence intervals for percentiles of the calculated Gaussian distribution and the percentage of cumulative points exceeding these limits. The process is to rank the reference values and plot the cumulative frequency points in a rankit plot with a logarithmic (In=log(e)) transformed abscissa. If the distribution is close to In-Gaussian the cumulative frequency points will fit to the straight line describing the calculated In-Gaussian distribution. The quality of the fit is evaluated by adding confidence intervals (CI) to each point on the line and calculating the percentage of points outside the hyperbola-like CI-curves. The assumption was that the 95% confidence curves for percentiles would show 5% of points outside these limits. However, computer simulations disclosed that approximate 10% of the series would have 5% or more points outside the limits. This is a conservative validation, which is more demanding than the Kolmogorov-Smirnov test. The graphical presentation, however, makes it easy to disclose deviations from In-Gaussianity, and to make other interpretations of the distributions, e.g., comparison to non-Gaussian distributions in the same plot, where the cumulative frequency percentage can be read from the ordinate. A long list of examples of In-Gaussian distributions of subgroups of reference values from healthy individuals is presented. In addition, distributions of values from well-defined diseased individuals may show up as In-Gaussian. It is evident from the examples that the rankit transformation and simple graphical evaluation for non-Gaussianity is a useful tool for the description of sub-groups.

Blood Chemical Analysis↗
PubMed2003

Evaluation of growth hormone stimulation tests in cured acromegalic patients.

UNLABELLED: We have evaluated the GH peak response to insulin tolerance test (ITT) and to GHRH+arginine in 11 patients cured of acromegaly after treatment with surgery/radiotherapy and compared them to a control group matched for age and sex. GH peak response was significantly higher in the control group than in the patient group (11.21+/-6.98 vs. 4.46+/-6.90 ng/ml, p=0.010). Seven patients had a GH peak response of less than 3 ng/ml, compatible with the diagnosis of GH deficiency. Peak GH response after GHRH+arginine was significantly lower in the group of patients with GH peak of less than 3 ng/ml during ITT as compared to the group with GH peak of more than 3 ng/ml, and in all cases the diagnosis of GH deficiency was confirmed. Mean IGF-I level was not different between the patients and controls, as well as between patients with and without GH deficiency diagnosed by the stimulation tests. CONCLUSION: The incidence of GHD diagnosed by stimulation tests is high in patients cured of acromegaly.

Acromegaly↗