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Smoking may reduce both the production and physiologic action of thyroid hormone. Thyrotropin from the pituitary gland stimulates the thyroid gland to produce thyroxine, which in turn is converted to active thyroid hormone, known as triiodothyronine. Researchers measured the levels of all of these hormones in 138 women with normal thyroid function, 84 with asymptomatic hypothyroidism, and 51 with symptomatic hypothyroidism. Among the normal women and those with symptomatic hypothyroidism, hormone levels were the same in non-smokers and smokers. However, among the women with asymptomatic hypothyroidism, smokers had higher cholesterol and thyrotropin levels and higher ratios of triiodothyronine to thyroxine. These comparisons indicate that smoking harms the thyroid gland and inhibits the action of thyroid hormone on cells. These effects of smoking may not be apparent in women with advanced hypothyroidism because their thyroid gland is already damaged.

Background: The effect of smoking on thyroid function is controversial, and its effect on thyroid hormone action is unknown. We investigated the effects of cigarette smoking in women with various grades of hypothyroidism and in normal women. Methods: We studied 138 normal women and 135 women with primary hypothyroidism, of whom 84 had subclinical hypothyroidism and 51 overt hypothyroidism. Sixty of the women with hypothyroidism were reevaluated during thyroxine therapy. The women were categorized as smokers or nonsmokers according to their responses to a questionnaire. Thyroid function was evaluated by measurements of serum thyrotropin, free thyroxine, and triiodothyronine. Peripheral thyroid hormone action was assessed by a clinical score and measurements of ankle-reflex time and serum lipids and creatine kinase. Results: Among the women with subclinical hypothyroidism, the smokers had a higher mean (±SD) serum thyrotropin concentration (21.3±16.6 vs. 12.7±7.2 mU per liter, P = 0.004) and a higher ratio of serum triiodothyronine to serum free thyroxine (by 30 percent, P = 0.003) than the nonsmokers. Their serum concentrations of total cholesterol and low-density lipoprotein (LDL) cholesterol were higher (by 16 percent, P = 0.013; and 28 percent, P = 0.003, respectively). Among the women with overt hypothyroidism, the serum concentrations of thyrotropin, free thyroxine, and triiodothyronine were similar in the smokers and nonsmokers. As compared with the nonsmokers, the smokers had a clinical score indicating a greater degree of hypothyroidism (P<0.001), higher serum concentrations of total and LDL cholesterol (by 25 percent, P<0.001; and 24 percent, P = 0.002, respectively), longer ankle-reflex time (by 25 percent, P<0.001), and higher serum concentrations of creatine kinase (by 236 percent, P<0.001). There were dose–response relations between smoking and serum concentrations of total and LDL cholesterol, serum creatine kinase concentrations, and ankle-reflex time in the women with overt hypothyroidism, and between smoking and serum concentrations of total and LDL cholesterol in the women with subclinical hypothyroidism. Conclusions: Smoking increases the metabolic effects of hypothyroidism in a dose-dependent way. This may be explained by alteration of both thyroid function and hormone action. (N Engl J Med 1995;333:964-9.) [ABSTRACT FROM AUTHOR]

The hCG stimulation test with assessment of serum testosterone (T) is used for evaluation of testicular function. This retrospective study was undertaken to estimate the diagnostic value of stimulated estradiol (E2) levels in the assessment of Leydig cell function. Serum T and E2 before and after repeated daily hCG injections in 23 adult men with clinically suspected or established primary hypogonadism were studied. After hCG administration serum T increased gradually with peak levels after 72 hours (delta84%, p=0.003). In contrast, serum E2 concentrations reached their maximal levels 24 hours after the first injection (delta168%, p=0.001). Serum T and E2 responses were more attenuated in men with LH > or =17 IU/L as compared to men with lower LH levels. Peak E2 levels after 24 hours correlated significantly with peak T levels after 3 days. We conclude that the increase in serum E2 levels 24 hours after a single hCG injection is an useful additional measure of Leydig cell function. Assessment of E2 increments would render the test procedure more practical, less time-consuming and more cost-effective than assessing peak T levels after 72 hours.

Principles: Since 1994 we have been removing most non-malignant classified pathologies of the adrenal gland laparoscopically. Does this minimal invasive procedure involve advantages over the conventional approach?, Methods: Retrospective analysis of 22 all-consecutive laparoscopic adrenalectomies in 21 patients (10 women, 11 men, age 26-70 years, mean 43 years, 11 right, 9 left, one bilateral in MEN IIa syndrome). These procedures were performed between 1994 and 2001 transperitoneally in the lateral decubitus position, recently by use of the Ultracision device and once with a handport. These results are compared with 20 consecutive open transperitoneal unilateral adrenalectomies with similar pathologies (13 women, 7 men, age 28-77 years, median 51.5 years, 8 right, 12 left) carried out between 1988 and 1993., Results: The mean operating times were 150 and 115 minutes with the laparoscopic and the open procedure respectively (p <0.011). On the other hand, mean hospital stay (6 versus 15 days, p <0.00001), intraoperative blood loss (200 versus 300 ml, p <0.04) and postoperative need for analgesics were significantly shorter or lower. Two out of the first five laparoscopic operations had to be converted into open adrenalectomy due to intraabdominal adhesions and a diaphragmatic injury with pneumothorax. In both groups three complications occurred (14% and 15%)., Conclusion: Laparoscopic adrenalectomy is a safe, effective and useful procedure involving a shorter hospital stay, lower intraoperative blood loss and a lower postoperative analgesics requirement compared with the open approach. The laparoscopic approach is the procedure of choice for all benign adrenal pathologies.