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Biomedical subjects

D A Koutras

Publications and source records attributed to D A Koutras.

At least 73 records · Page 4Linked to original sources
PubMed1986

The effect of benziodarone on the thyroid hormone levels and the pituitary-thyroid axis.

The effect of benziodarone on the levels of thyroid hormones in the serum has not attracted interest, in spite of the prolific literature on the related drug amiodarone. It is shown here that benziodarone administration has several effects, mainly similar to amiodarone, but some possibly opposite and inappropriate. Nine normal volunteers received benziodarone, 100 mg three times daily for 14 days. Before and 1, 3, 7 and 14 days after continuous administration the following estimates were obtained: serum T4, T3, rT3 and TSH, both basal (TSH0) and 30 min after iv administration of TRH (TSH30), the difference being calculated as delta TSH. Serum T4 remained relatively constant. Serum T3 decreased significantly from the 1st to the 14th day (eg. before 2.15 +/- 0.12 nmol/l, at 3 days 1.45 +/- 0.07). Serum rT3 increased significantly from the 1st to the 14th day (eg. before 0.71 +/- 0.16 nmol/l, at 7 days 2.61 +/- 0.19). Serum TSH0 and TSH30 decreased significantly on the 1st and 3rd day. Later they increased, and TSH0 at 14 days was significantly higher than the pre-treatment value. Our results suggest that benziodarone has an amiodarone-like action in diverting the peripheral metabolism of T4 towards rT3 rather than T3. However, the effects on the pituitary-thyroid axis are not similar to those previously reported by others and ourselves about amiodarone, and these merit further research.

Adult↗
PubMed1986

Effects of six weeks' neuroleptic treatment on the pituitary-thyroid axis in schizophrenic patients.

In order to investigate the effects of 6 weeks' neuroleptic treatment on the pituitary-thyroid axis in 25 male schizophrenic patients, and the diurnal variation in the thyrotropin (TSH) and prolactin (PRL) responses to thyrotropin-releasing hormone (TRH) in these patients, the TRH stimulation test was performed in each of them at 14.00 and 24.00 h of the same day, both before and after 6 weeks' treatment with neuroleptics (chlorpromazine or fluspirilene). Also, serum thyroxine (T4), in vitro radioactive triiodothyronine uptake (RT3 U) and free-thyroxine index (FTI) values were estimated from the pre-TRH blood sample. We found no evidence of diurnal variation in the TSH response to TRH in the schizophrenic patients, before or after 6 weeks' neuroleptic treatment. Only drug-free schizophrenic patients had significantly higher PRL responses to TRH at 14.00 h than those at 24.00 h. After 6 weeks' neuroleptic treatment, schizophrenic patients tended to have lower FTI values; also, they had significantly higher basal TSH and PRL values, as well as significantly augmented TSH and PRL responses to TRH, in comparison to their pretreatment values. These findings render possible the diagnosis of subclinical hypothyroidism in neuroleptic-treated schizophrenic patients.

Adolescent↗
PubMed1986

Treatment of endemic goitre with iodine and thyroid hormones, alone or in combination. (Preliminary report).

108 patients with endemic nontoxic goitre have been treated in the field with thyroxine (T4), triiodothyronine (T3), and potassium iodide (KI), singly or in combination, or with placebo. After 6 months of continuous treatment, goitre size decreased significantly in the 7 actively treated groups, but not in the one treated with placebo. The combination of 150 micrograms T4 + 150 micrograms KI daily seemed the most effective treatment, both clinically and by its suppression of the 131I uptake and the TSH response to TRH, followed by 100 micrograms T4 + 25 micrograms T3 or 200 micrograms T4, but the difference from the other groups was not statistically significant. The increase in the pulse rate (PR) and the shortening of the photomotogram of the Achilles tendon reflex (PMG) were taken as indices of thyrotoxicity and side-effects of the treatment. There was no significant difference in the side-effects between any two of the active groups if effectiveness was also taken into account. The decrease in goitre size was not correlated to either the final serum T3 value achieved at the end of the treatment, or the thyroidal 131I uptake. There was, however, a weak but significant correlation between the decrease in goitre size and the TSH response to TRH. This casts some doubt to the concept that thyroid hormones decrease goitre size solely by suppressing the pituitary TSH release. Of the 30 patients treated with KI singly or in combination and studied in this respect, 8 developed autoantibodies against thyroglobulin and/or the thyroidal microsomal antigen compared to 1 of 22 not receiving KI (P = 0.08).(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗
PubMed1984

The correlation of serum amiodarone levels with abnormalities in the metabolism of thyroxine.

Amiodarone, a widely used iodine-containing antiarrhythmic drug, has been shown to divert the peripheral metabolism of T4 towards rT3 than T3. In this prospective study we correlated the concentration of the peripheral thyroid hormones in serum with that of amiodarone. Fifteen euthyroid volunteers were studied, 5 men and 10 women, with a mean age of 64.2 yr, who suffered from various cardiac arrhythmias (atrial fibrillation or multiple ventricular extrasystoles). Serum amiodarone, T4, T3, rT3 and TSH were determined before and 3, 7, and 14 days after the administration of 400-600 mg amiodarone/day. There was a small increase in serum T4 and a suggestive decrease in serum T3. The increase in serum rT3 was significant, with p less than 0.05 for 3 days, p less than 0.01 for 7 days and p less than 0.005 for 14 days. There was a significant correlation between the level of serum amiodarone and the rise in serum rT3 (r = 0.385, p less than 0.05). The rise in rT3 is the main thyroid abnormality after amiodarone administration and may be used as a rough index of the serum concentration of this drug.

Aged↗
PubMed1984

Pituitary and thyroid insufficiency in thalassaemic haemosiderosis.

Thyroid and pituitary function tests using hypothalamic releasing factors were performed in seven patients with thalassaemia and secondary haemosiderosis and in a control group of seven healthy subjects. The TSH level in the thalassaemic patients (18.07 +/- 1.10 microU/ml) was higher than in the controls (1.01 +/- 0.14 microU/ml, P less than 0.001). After TRH administration the TSH values increased less than in controls. Serum thyroxine and FT41 values were lower in the group of patients with thalassaemia (76.7 +/- 7.8 nmol/l and 19.3 +/- 2.2) compared to the controls (116.1 +/- 6.9 nmol/l, P less than 0.005 and 38.6 +/- 3.6, P less than 0.001). The basal prolactin values did not differ significantly between the two groups, but after TRH administration the increment was significantly lower in thalassaemics than in controls (P less than 0.005). The basal LH values were lower in the thalassaemic patients (1.37 +/- 0.24 ng/ml) than in the controls (3.23 +/- 0.50 ng/ml) and did not increase significantly after LHRH administration. The FSH values were also lower in the thalassaemic group (0.46 +/- 0.15 ng/ml) compared to the controls (2.06 +/- 0.08 ng/ml, P less than 0.001), and increased only slightly after LHRH administration. We conclude that in thalassaemia pituitary deficiency exists, mostly of gonadotrophs, but possibly also for the thyrotrophs and the lactotrophs. Latent primary hypothyroidism has also been found in the thalassaemic group. The functional abnormalities found in both endocrine glands are best explained as a consequence of coexisting haemosiderosis.

Adolescent↗
PubMed1983

Thyroid hormone and immunological studies in endemic goiter.

Iodized oil (1 ml im) was given to 58 goitrous patients from a mildly iodine-deficient area in Greece. Goiter size, urinary iodine, and serum T4, T3RU, T3, rT3, TSH, thyroxine-binding globulin (TBG), and thyroid autoantibodies were measured before and 1, 3, and 6 months after the injection. Goiter size decreased. Serum T4 remained relatively constant, but TBG decreased and therefore T3RU and FTI increased. Serum T3 and rT3 initially decreased (P less than 0.001) and then increased at the sixth month (P less than 0.001), both showing roughly parallel changes. Serum TSH, initially normal (1.42 +/- 0.11 (SEM) mU/liter), decreased to 0.65 +/- 0.01 and 0.76 +/- 0.05 mU/liter at the third and sixth month (difference from baseline P less than 0.001). Thyroid autoantibodies, both against thyroglobulin and the microsomal antigen, were undetectable before treatment, but became positive in 42.8% of the patients 3 and 6 months later. Three patients developed transient hyperthyroidism. This occurred 3 or 6 months after treatment, and was associated with high titers of thyroid autoantibodies. These results indicate that: 1) transient hyperthyroidism may occur after the administration of iodized oil, possibly because of thyroid tissue necrosis and leakage of hormones, and 2) serum TBG decreases after iodized oil, a finding not previously reported and one whose cause is not known.

Adult↗
PubMed1982

An epidemiologic survey of thyroid enlargement among schoolchildren in a non-endemic area.

In 534 unselected schoolchildren aged 6-14 yr from the greater Athens area the size of the thyroid gland was assessed by palpation, and information was obtained on sex, age, height, weight, skinfold thickness, socioeconomic class, eye colour and urinary iodine excretion. The results were analysed by discriminant analysis. Altogether 14% of these children had a thyroid enlargement (7% had a definite goitre and another 7% a smaller enlargement). The set of variables studied were significantly discriminatory (Wilk's lambda 0.926, p approximately equal to 0.004). Most of the discrimination was accounted for by height (positive association, b coefficient 0.0114, SE 0.0029, t = 3.95) and weight (negative association, b coefficient 0.0107, SE 0.0030, t = 3.61). No other parameter, including iodine excretion, showed a significant difference between goitrous and nongoitrous. It is concluded that the only genuine difference is that goitrous are heavier for a given height or shorter for a given weight, i.e. more obese. The reason for which obesity protects from sporadic nontoxic goitre is not entirely clear, but probably both nutritional and genetic factors are involved.

Adolescent↗
PubMed1981

Metabolic insufficiency as a limiting factor in the dietetic treatment of obesity.

Previous observations that acute total fasting decreases serum T3 and increase rT3 has prompted the following study. 17 obese women were placed on a 1000 kcal/day weight-reducing diet, and body weight (BW), serum T4, RT3U, T3, rT3, TSH and the Achilles tendon reflex (ATR) were estimated before and after each month for 3 consecutive months of the diet. The results showed a consistent decrease in serum T3, and inconsistent increase in rT3, a consistent prolongation of the ATR and a levelling-off of the BW loss after the second month of the diet. At 3 months there was a negative correlation between the decrease in BW and the increase in ATR, i.e. the more abnormal the ATR became, the less weight the patient lost. It is concluded: 1) Even a moderate hypocaloric diet in ambulatory patients induces a disturbance in the peripheral conversion of T4 to T3 and a secondary state of metabolic insufficiency. 2). This insufficiency is probable related to the observed tendency of the BW loss to level off after two months. 3) A controlled trial of physiologic doses of T3, such as 40 mu g/day, seems indicated, as opposed to pharmacologic dosed of T3 used by previous investigators.

Achilles Tendon↗
PubMed1981

The effects of mild iodine deficiency on neonatal thyroid function.

In order to assess neonatal thyroid function in the endemic goitre areas of Greece, T4 and TSH have been measured. Previous studies had shown that in these endemic areas, adults had low T4 but normal TSH values, probably because of an increase in the serum T3 level. In this study, T4 and TSH were measured in dried blood spots from 259 neonates. The fifty-four full-term neonates from the Greek endemic villages had a lower T4 value (8.8 +/- 0.66 micrograms/dl SE) but a higher TSH (15.37 +/- 1.12 mu/l) than the seventy-three full-term neonates from the non-endemic villages (T4:10.0 +/- 0.33 micrograms/dl, TSH:11.93 +/- 0.59 mu/l) or the ninety-eight from Athens (T4:10.0 +/- 0.33 micrograms/dl, TSH:10.96 +/- 0.64 mu/l). Premature neonates, both from Athens and from the endemic areas, have significantly lower T4 and significantly lower TSH values than the full-term ones from the same areas, probably because of the immaturity of the pituitary-thyroidal axis. It is concluded from these observations that (a) Neonates suffer more from the consequences of iodine deficiency than adults. The biochemical hypothyroidism reported here may be relevant to the delayed skeletal maturation previously reported from children of these same areas. This emphasizes the need for correcting even moderate iodine deficiency. (b) The occurrence of non-toxic goitre with normal TSH levels in adults is best explained by assuming that increased TSH stimulation is necessary for goitre formation during neonatal life, but not for goitre maintainance during adulthood. (c) Newborn screening programmes in these areas should take into account the present findings.

Female↗
PubMed1981

Some epidemiologic studies of HBSAg in Greece.

In an epidemiologic study in 17 villages from different areas of Greece, 2898 persons were examined in order to find possible relations between HBSAg prevalence, altitude and endemic goitre morbidity. A lower prevalence with a significant difference was found in areas with a high altitude as compared with those with a low one, in endemic goitre than non-endemic areas, and in low altitude endemic than in low altitude non-endemic areas. Goitrous subjects had a lower HBSAg prevalence than non-goitrous subjects, but the difference was of borderline significance. The results can probably be explained by the presence of an environmental factor associated with altitude acting together with a host factor predisposing to endemic goitre and favouring the immunity to HBV infection.

Altitude↗
PubMed1980

Free-thyroxine index in schizophrenic patients before and after neuroleptic treatment.

The mean values of serum thyroxine (T4), in vitro radioactive triiodothyronine uptake and free-thyroxine index (FTI) in 41 drug-free schizophrenic patients did not differ significantly from those of euthyroid controls. Following 6 weeks' treatment of 24 schizophrenics with chlorpromazine, trifluoperazine or clozapine, a significant decrease in serum T4 and FTI was noted after chlorpromazine and clozapine, whereas after trifluoperazine only serum T4 decreased, but not FTI. The questions arising from these findings are discussed and the need for a future investigation of serum triiodothyronine and serum TSH in schizophrenic patients before and after neuroleptic treatment is stressed.

Adolescent↗
PubMed1979

The radiological assessment of body fat.

A radiological method for assessment of obesity is described. A radiograph of the soft tissues of the upper arm is obtained and the subcutaneous fat layer measured. The results obtained by this method have been compared with those using a skinfold caliper and with the ponderal index, calculated from the height and weight of the subject. A highly significant correlation was found. The radiological method has several advantages: it leaves a permanent record, it is accurate in obese persons when the skinfold caliper cannot be used, and unlike the ponderal index it is not influenced by weight increases due to causes other than fat accumulation.

Adipose Tissue↗