Association of common carotid intima-media thickness and lipoprotein(a) with coronary artery disease.

BACKGROUND: Carotid artery intimal medial thickness is a simple, non-invasive and reproducible clinical tool to evaluate atherosclerosis and predict coronary artery disease. Lipoprotein(a) levels are related to both atherogenesis and thrombogenesis and may be a key link between lipid and coronary artery disease. This study evaluated the association of carotid intimal medial thickness and lipoprotein(a) with coronary artery disease. METHODS AND RESULTS: We studied 185 randomly selected patients hospitalized for coronary angiogram in our institute. There were 110 angiographically proven patients of coronary artery disease with mean age of 55.8 +/- 9 years (range 34-72 years) and 75 subjects with normal coronary artery anatomy with mean age of 54.8 +/- 8 years (range 34-68 years). The mean carotid intimal medial thickness of subjects with coronary artery disease was significantly higher than in subjects without coronary artery disease (0.84 +/- 0.16 mm v. 0.65 +/- 0.15 mm, p<0.001). The mean carotid intimal medial thicknesses in patients with triple vessel, double vessel and single vessel disease were 0.96 +/- 0.12 mm, 0.84 +/- 0.11 mm and 0.78 +/- 0.13 mm, respectively (p=0.05). The mean lipoprotein(a) of subjects with coronary artery disease was significantly higher than in subjects without coronary artery disease (35.9 +/- 22.3 mg/dl v. 19.1 +/- 21.2 mg/dl, p<0.001). Mean lipoprotein(a) levels in subjects with carotid intimal medial thickness <0.80 was 26.4 +/- 24.2 mg/dl and in subjects with carotid intimal medial thickness > or = 0.80 was 32.1 +/- 22.1 mg/dl (p=0.05). CONCLUSIONS: There is a strong correlation between carotid and coronary atherosclerosis and carotid intimal medial thickness is a good predictor of presence and extent of coronary artery disease. Lipoprotein(a) level is a powerful independent risk factor for atherosclerosis. Carotid intimal medial thickness and lipoprotein(a) in conjoint can predict coronary artery disease reliably.

Effect of oophorectomy on expression of calcium sensing receptor mRNA in rat duodenal mucosa.

Calcium sensing receptor (CaR) in duodenal mucosa may be involved in active calcium absorption. Estrogen deficiency results in decreased intestinal calcium absorption. Effects of bilateral oophorectomy (OVX) have been studied on calcium homeostasis, bone mineral density (BMD) and CaR mRNA levels in duodenal mucosa at 4 weeks in adult female Sprague Dawley rats and compared with those in sham-operated and control group. There was no significant change in serum corrected calcium, inorganic phosphorous, calcidiol and intact parathyroid hormone in all the three groups. OVX rats had a significant decline in serum estrogen (E2) levels and alkaline phosphatase. They also had a significant decrease in BMD (DXA) at lumbar spine in vivo, and proximal and distal tibia in vitro while there was no significant change in serum E2 and BMD parameters in sham-operated and control rats. Northern blot analysis revealed no significant change in the CaR mRNA expression in duodenal mucosa in all three groups. The results suggests that CaR mRNA expression in duodenal mucosa is not affected by physiological circulating concentrations of estradiol in rats.

Short-term androgen deprivation does not alter CaR and VDR mRNA expression in duodenal mucosa in male rats.

Androgen deprivation is associated with decline in intestinal calcium absorption. The effect of androgen on CaR and VDR intestinal mucosa has not yet been studied. Calcium homeostasis, a real bone mineral density (aBMD, dual energy X-ray absorptiometry) and expression of CaR and VDR mRNA in duodenal mucosa of orchidectomized (ORX) and sham operated (Sham) adult Sprague Dawley rats at 4 week have been studied. There was no significant difference in serum calcium, alkaline phosphatase, calcidiol and calcitriol levels between both the groups. Serum testosterone (T) (ng/dl) and inorganic phosphorous (iP) (mg/dl) levels were significantly lower in ORX rats. As compared to sham rats, ORX rats had significant decline in in-vitro aBMD at proximal, middle and distal tibia, proximal, mid and distal femur and femoral neck (P < 0.05). Northern blot analysis revealed no significant alteration in the CaR and VDR mRNA expression in duodenal mucosa in ORX rats. CaR and VDR mRNA expression in duodenal mucosa is therefore, not affected by physiological concentrations of testosterone in rats.

Plasma lipoprotein(a) levels in patients with pulmonary arterial hypertension.

BACKGROUND: Pulmonary artery hypertension is a common sequelae of a variety of cardiac and lung diseases. Pathogenesis of primary and secondary pulmonary artery hypertension is still debatable. METHODS AND RESULTS: We studied the serum lipoprotein(a) levels in patients with primary (n=27) and secondary (n=19) pulmonary artery hypertension (Eisenmenger syndrome). The results were compared with age and sex matched controls (n=46). We also studied the frequency of high levels of lipoprotein(a) (> 30 mg/dl) in pulmonary artery hypertension. Mean lipoprotein(a) levels were significantly higher in the pulmonary artery hypertension group compared to age- and sex-matched controls (31.60+/-15.49 mg/dl v. 14.66+/-14.7; p=0.0001). All patients were classified into two groups on the basis of their lipoprotein(a) levels (<30 mg/dl and >30 mg/dl). There was a higher frequency of lipoprotein(a) >30 mg/dl in patients of pulmonary artery hypertension v. controls (52% v. 24%; p= <0.001). Younger age, higher functional class, more severe congestive heart failure, shorter duration of symptoms. and more cases of hemoptysis were observed in the group with lipoprotein(a) >30 mg/dl. CONCLUSIONS: High lipoprotein(a) may be a marker and be associated with a more adverse prognosis in severe pulmonary artery hypertension. Larger prospective studies are needed to establish lipoprotein(a) as a risk factor for the development of pulmonary artery hypertension.

Extraovarian endocrine abnormalities in north Indian women with premature ovarian failure.

BACKGROUND. Premature ovarian failure is a rare syndrome characterized by cessation of menstruation before 35 years of age associated with an elevated gonadotropin level (serum follicle stimulating hormone > 40 IU/L) and oestrogen deficiency. Premature ovarian failure is often the result of an autoimmune process and involvement of other endocrine glands has been reported but available studies are hampered by a lack of uniformity in diagnostic criteria. METHODS. The endocrine profile of 37 north Indian women with premature ovarian failure was studied. The investigations included measurement of serum follicle stimulating hormone, luteinizing hormone, oestradiol, prolactin, total thyroxine, total triiodothyronine and thyroid stimulating hormone. To assess adrenocortical reserve, adrenocorticotropic hormone stimulated plasma cortisol levels were estimated. RESULTS. Eighteen (49%) patients had extraovarian endocrine abnormalities. Eight (22%) had abnormal thyroid function tests and 12 of 29 (41%) patients tested for adrenocortical reserve showed impaired response of plasma cortisol to adrenocorticotropic hormone stimulation. CONCLUSION. Extraovarian endocrine (especially adrenocortical) involvement is frequent in patients with premature ovarian failure. Because none of the patients had overt clinical evidence of thyroid or adrenocortical disease, we suggest that tests for thyroid and adrenal function be performed routinely in females presenting with premature ovarian failure.

Single daily dose of carbimazole in the treatment of hyperthyroidism.

BACKGROUND. The antithyroid drugs, methimazole and carbimazole, are conventionally used in divided daily doses. However, these drugs have a longer intrathyroidal than a plasma half-life. We undertook this prospective, controlled study, in an area of mild iodine deficiency, to compare the efficacy of a single daily dose of carbimazole with divided doses in the treatment of hyperthyroidism. METHODS. Nineteen patients with hyperthyroidism received 30 mg of carbimazole daily at bed time (group A) while 14 received 10 mg of carbimazole every 8 hours (group B). These patients were assessed clinically and biochemically by estimation of serum total thyroxine, total triiodothyronine and thyrotropin before and 1, 2, 3, 4 and 6 weeks after treatment. RESULTS. There was no significant difference between mean baseline concentrations of thyroxine and triiodothyronine. After 1, 2, 3, 4 and 6 weeks there was a decline in their concentrations which was similar in both groups (p > 0.05). Euthyroidism was achieved in 4.6 +/- 1.4 weeks (range 2-6 weeks) in group A and in 3.8 +/- 1.2 weeks (range 3-6 weeks) in group B (p > 0.05). CONCLUSIONS. We conclude that carbimazole in a single daily dose is an effective method for treating hyperthyroidism in an area of mild iodine deficiency and its efficacy is comparable to divided dose therapy. This practical and acceptable method of treatment can be specially useful in patients who find it difficult to remember to take divided doses.

Iopanoic acid as an adjunct to carbimazole in the management of hyperthyroidism.

BACKGROUND. The thiourea drugs take a few weeks to control the symptoms of hyperthyroidism whilst iodine containing radiographic contrast agents (iopanoic acid and sodium ipodate) have a more rapid effect. There is no report on the use of iopanoic acid administered in conjunction with carbimazole, so we evaluated the efficacy of this combination in the early medical management of patients with hyperthyroidism. METHODS. Thirty hyperthyroid patients diagnosed by clinical and biochemical criteria were randomized into two treatment groups. Group A (n = 16) received iopanoic acid (500 mg orally twice a day for the first 3 weeks) and carbimazole (30 mg orally in three divided doses) while group B (n = 14) received carbimazole alone. Clinical examination and estimation of serum total T3, total T4 and TSH were done by radioimmunoassay at the start of therapy, weekly for 4 weeks and then at 6, 8 and 12 weeks. RESULTS. In the initial 3 weeks, iopanoic acid induced a significantly greater fall in mean serum total T3 levels (Z = 2.298, p < 0.02) and a slower fall in mean serum total T4 (Z = 2.396, p < 0.05) in group A patients compared to those in group B. This was accompanied by earlier clinical improvement in group A patients. The mean serum total T3 and T4 values rose to higher levels in group A at 4 weeks, one week after discontinuation of iopanoic acid. At the end of 12 weeks, however, there was no significant difference in the mean serum total T3 and T4 levels between the two groups (p > 0.05). Biochemical euthyroidism (i.e. total T3 < 3 nmol/L and total T4 < 170 nmol/L) was achieved later in group A patients than in group B (10.4 +/- 5.0 weeks v. 3.6 +/- 1.2 weeks, p < 0.0001). CONCLUSIONS. Iopanoic acid given together with carbimazole induces rapid clinical improvement in hyperthyroid patients than carbimazole alone. However, the delayed achievement of euthyroidism may preclude its routine use in the management of patients with hyperthyroidism except in those with thyrotoxic emergencies.