A. G. H. Smals

Osteopenia in insulin-dependent diabetes mellitus; prevalence and aspects of pathophysiology

The objective was to evaluate the prevalence and severity of osteopenia in patients with uncomplicated insulin-dependent diabetes mellitus (IDDM) and to obtain more information on the pathophysiology of diabetic osteopenia. In 35 patients with uncomplicated IDDM (21 men and 14 women; age 37.6±9.9 yr; duration of disease 8.5±3.5 years) bone mineral density was measured by dual energy X-ray absorptiometry (DEXA). In addition, markers of bone formation [plasma insulin-like growth factor I (IGF-I), serum alkaline phosphatase (ALP), serum bone alkaline phosphatase (BAP) and serum osteocalcin] and bone resorption [urinary excretion of calcium and of the cross-linked N-telopeptide of type 1 collagen, both corrected for the excretion of creatinine] were measured in the diabetic patients and in 33 healthy controls, matched for sex, age, height, weight and body mass index (BMI). In 67% of the diabetic men and 57% of the diabetic women osteopenia of the femoral neck and/or the lumbar spine (T-value ≤−1 SD) was present. Fourteen percent of the male patients, but none of the female patients, met the criteria for osteoporosis (T-value ≤−2.5 SD). In the whole group of diabetic patients the mean plasma IGF-I level tended to be lower (p<0.10) as compared to that in the controls. In the diabetic patients with femoral neck osteopenia, the mean plasma IGF-I level was significantly lower (p<0.05) than in those without osteopenia at this site. There were no differences in the mean serum ALP, BAP and osteocalcin levels between the diabetic patients and the controls, nor between the diabetic patients with and without femoral neck osteopenia. Considering only the male diabetic patients, significantly lower mean plasma IGF-I (−26%), serum ALP (−24%) and serum osteocalcin (−38%) levels were present in the patients with femoral neck osteopenia than in those without osteopenia at this site, suggesting lowered bone formation. The bone resorption markers were similar in all (sub)groups of diabetic patients and not different between diabetic patients and controls. Bone mineral density (BMD) did not correlate with plasma levels of glycosylated hemoglobin (HbA1c). BMD values were not related to any of the bone resorption or formation markers, except for plasma IGF-I both in the femoral neck (r=+0.38, p=0.026) and the lumbar spine (r=+0.34, p=0.043). Our data demonstrate that at least in male patients with IDDM, osteopenia is the consequence of a lowered bone formation with a predominance of bone resorption over formation.

Adrenocortical function: an indicator of severity of disease and survival in chronic critically ill patients

Plasma cortisol levels and modified Apache II (Apache IIm-stay) severity of disease scores were determined at weekly intervals in 159 patients who were treated for at least 7 days at the Critical Care Unit of our hospital. The mean (±SD) plasma cortisol level (0.60±0.28 μmol/l) was clearly elevated in these patients. The highest plasma cortisol levels were measured in patients treated with vasoactive drugs (0.76±0.39 μmol/l). Non-survivors (n=36) had a significantly higher mean plasma cortisol level and Apache IIm-stay score than survivors (respectively 0.78±0.40 vs. 0.54±0.21 μmol/l;p<0.0003 and 12.6±4.8 vs. 7.3±4.1;p<0.0001). A significant correlation was found between the individual weekly plasma cortisol levels and the Apache IIm-stay scores (r=0.41;p<0.0001), especially in the subgroup of patients, who never received glucocorticoids during their stay at the ICU (r=0.51;p<0.0001). During the 14-month study period only two patients showed a clinical picture of adrenocortical insufficiency and a blunted response of cortisol to 0.25 mg synthetic ACTH(1-24). In conclusion, our data suggest that a high plasma cortisol level, like a high Apache IIm-stay score, indicates severity of disease and poor survival in critically ill patients. De novo adrenocortical insufficiency is rare and therefore routine screening of adrenocortical function is superfluous.

STEROID HORMONE RECEPTOR ACTIVITY OF PRIMARY HUMAN BREAST CANCER AND PATTERN OF FIRST METASTASIS

SummaryA series of 258 breast cancer patients with known estrogen receptor (ER) status of the primary tumour who subsequently developed metastases were reviewed for site of first metastasis. In 188 cases progesterone receptor (PgR) data were also available.Univariate analysis showed metastatic patterns to differ statistically significantly related to ER status and (less pronounced) PgR status of the primary tumour. Patients with ER-positive tumours had bone metastases three times more often than patients with ER-negative tumours. With respect to PgR-positive and PgR-negative tumours this frequency differed by a factor of two. With regard to visceral metastases ER and PgR status were equally potent prognosticators, patients with receptor negative tumours having a 50% higher frequency of visceral metastasis than patients with receptor positive tumours. Assessment of metastatic patterns in relation to combined receptor status did not substantially enhance the discriminatory value of ER and PgR when assessed separately.Multivariate analysis showed that the observed differences in metastatic patterns were all attributable to differences in the ER status of the primary tumour, and were not influenced by age, menopausal status, axillary lymph node involvement, duration of disease-free interval (DFI), mode of postoperative treatment, or the PgR status of the primary tumour.

Human breast cancer: survival from first metastasis

SummarySurvival from the detection of first metastasis (SAM) was analyzed in a single center series of 258 patients with advanced breast cancer. During the 15 year period covered by this study 230 patients died, 215 of their disease. The overall median SAM was 28 months.Univariate analysis of SAM stratified by first dominant site of metastasis, estrogen receptor status (ER), progesterone receptor status (PgR), tumor size, axillary lymph node status, patient age, menopausal status, and disease-free interval (DFI) showed the first dominant site of metastasis, ER, PgR, and axillary lymph node status to be significantly associated with SAM. Patients with visceral metastasis as first dominant site of metastasis had significantly shorter survival than those with either bone or soft tissue metastasis, median SAM 16 vs. 34 vs. 41 months respectively (P<0.001). SAM also differed according to the steroid hormone receptor status of the primary tumor: median SAM 34 and 33 months for patients with ER-positive or patients with PgR-positive tumors against 14 months for patients with ER-negative or with PgR-negative tumors (P<0.001). Patients with axillary lymph node involvement at primary disease had a shorter SAM than those without, median SAM 24 vs. 35 months (P=0.006). No association between SAM and either tumor size, patient age, menopausal status, or DFI could be observed.Multivariate analysis including first dominant site of metastasis, ER, PgR, and axillary lymph node status showed the first dominant site of metastasis, ER, and axillary lymph node status to be independently associated with SAM.

THE CORTICOTROPIN-RELEASING-HORMONE TEST VERSUS THE HIGH-DOSE DEXAMETHASONE TEST IN THE DIFFERENTIAL DIAGNOSIS OF CUSHING'S SYNDROME

The diagnostic accuracy of the corticotropin-releasing-hormone (CRH) test was compared with that of the oral high-dose dexamethasone suppression test in the differential diagnosis of Cushings syndrome. A false-negative response to CRH was present in 9% (2 of 22) of patients with pituitary-dependent Cushings disease and to high-dose dexamethasone in 11% (2 of 18). All 3 patients with Cushings syndrome due to an adrenal adenoma were unresponsive to both CRH and dexamethasone. The only patient with ectopic corticotropin secretion had a false-positive response of corticotropin to dexamethasone and no response of corticotropin to CRH. Simultaneous failure of both tests to indicate the cause of Cushings syndrome did not occur in this series, except in 1 patient with Cushings disease and overt macronodular hyperplasia. It is concluded that the diagnostic accuracy of the CRH test in patients with Cushings syndrome is comparable to that of the high-dose dexamethasone test and that the highest discriminatory score in the differential diagnosis of Cushings syndrome is achieved by using both a CRH test and a high-dose dexamethasone test.

Disease-free interval and estrogen receptor activity in tumor tissue of patients with primary breast cancer: analysis after long-term follow-up

SummarySpecific estrogen receptor activity (ER) was found in 115 of 175 (66%) tumors of patients treated for primary breast cancer in the period 1974–1981; 60 patients had ER-negative tumors. All patients were under observation for at least 48 months (median 76 months). The 24 patients who received adjuvant chemotherapy as part of their initial treatment, were excluded from the analysis of the disease-free interval (DFI). Groups of patients with ER-positive or ER-negative tumors did not differ significantly in clinical characteristics. Patients with ER-positive tumors had a significantly longer DFI than those with ER-negative tumors only in the first year after initial treatment. After prolonged observation a significant difference in recurrence rates was no longer found. In premenopausal women, the DFI was not different for those with ER-positive compared to those with ER-negative tumors, not even in the first year of observation. However, in postmenopausal women, those with ER-positive tumors had a significantly longer DFI up to 3 years after initial treatment but not thereafter. There was no difference in DFI between the ER-positive and ER-negative groups when the tumor stage was taken into account. It is concluded that the ER status of the primary tumor affects prognosis only on the short term.

HUMAN PANCREATIC GROWTH HORMONE RELEASING HORMONE FAILS TO STIMULATE HUMAN GROWTH HORMONE BOTH IN CUSHING'S DISEASE AND IN CUSHING'S SYNDROME DUE TO ADRENOCORTICAL ADENOMA

An absent or severely blunted hGH response to an i.v. bolus injection (100 μg) of human pancreatic growth hormone releasing hormone (hpGRF1–44) was found in seven female patients with Cushings syndrome (five with pituitary dependent Cushings disease and two due to an adrenal adenoma) and four men with pituitary dependent Cushings disease. Three of the female and three of the male patients had an adequate hypoglycaemia after insulin administration. All these patients showed an absent or blunted hGH response after insulin induced hypoglycaemia. The GHRH data in these patients are in agreement with those in older literature on hGH responsiveness to stimuli such as L‐dopa, arginine and insulin induced hypoglycaemia. It is concluded that hypercortisolism inhibits hGH release to various stimuli at the pituitary level.

The mechanism of the synthesis of 16-androstenes in human testicular homogenates.

The biochemical pathway leading to the 16-unsaturated C19 steroids--known as sex pheromone (precursors) in pig and man--is still a matter of dispute. In the 16-ene-synthetase process, via which 5,16-androstadien-3 beta-ol (ADL) or 4,16-androstadien-3-one (ADN) are biosynthesized from pregnenolone (P5) or progesterone (P4), a number of 2 or even 3 step conversions have been suggested in porcine tests, including 20 beta-reduction, 21-hydroxylation and 16,17-dehydrogenation. Studying the 16-ene-synthetase reaction in human testicular homogenates, we adduced evidence for the hypothesis that ADL is synthesized from P5 in a single step, not requiring separate intermediates. Our proposal for the 16-ene-synthetase mechanism also explains why, at least in our hands, synthesis of ADL is always accompanied by co-synthesis of its satellite 5-androstene-3 beta,17 alpha-diol (epiA5): both steroids are synthesized as a mere consequence of the fact that the proposed elimination and substitution reactions for the synthesis of ADL and epiA5, respectively, are competitive processes.

Hypotensive effects of ovine and human corticotrophin-releasing factors in man

SummaryThe haemodynamic effects of i.v. bolus injections of 100 and 200 µg ovine CRF and human CRF in man have been compared. Neither ovine CRF 100 µg nor human CRF 100 µg caused a significant change in blood pressure, although the pulse rate was increased in all the subjects tested. The mean maximum increase in pulse rate after human CRF was almost twice that after ovine CRF (21 vs 12 beats·min−1;p<0.05). After 200 µg ovine CRF in all subjects the diastolic blood pressure declined gradually from 77 mm Hg to a nadir of 67 mm Hg at 22 min (p<0.002). After 200 µg human CRF diastolic blood pressure fell from 78 mm Hg to a nadir of 61 mm Hg at 6 min (p<0.002); the fall after human CRF was significantly greater than after ovine CRF (p<0.05). After 200 µg ovine CRF there was a slight increase in pulse rate lasting for 6 min, and after 200 µg human CRF there was a marked (reflex) tachycardia for 30 min. Only after the highest dose of human CRF did a slight increase in systolic blood pressure occur. The haemodynamic effects of both doses of human CRF were accompanied by significant increases in plasma noradrenaline concentrations, which were significantly greater after the higher dose.

Progesterone receptor activity and relapse-free survival in patients with primary breast cancer: the role of adjuvant chemotherapy

The prognostic significance of progesterone receptor activity (PgR) with regard to the estimated relapse-free survival (RFS) was studied in 350 one-center patients with primary breast cancer. All receptor assays were performed in one laboratory; PgR levels >10 fmol/mg protein were considered positive. Univariate as well as multivariate statistical analyses were used to examine the prognostic significance of several variables. Eighty-nine of the 350 patients received adjuvant CMF chemotherapy (cyclophosphamide, methotrexate, and 5-fluorouracil). The median observation period was 69 months (range 12–125 months).In the group of 261 patients who did not receive adjuvant CMF, the PgR-status lacked prognostic significance; only the lymph node status significantly affected the RFS (p<0.00001). In contrast, in the CMF-treated group of patients, the PgR-status was the most powerful predictor of recurrence (p<0.0001). The menopausal and the lymph-node status increased the predictive value of PgR (p<0.001). Premenopausal CMF-treated patients with PgR+ tumors had a significantly longer RFS than those with PgR− tumors (p<0.02). The present data urge the need for a reappraisal of the prognostic significance of PgR and of the mechanism of action of adjuvant chemotherapy in primary breast cancer.