Saara Metso

Long-term follow-up study of radioiodine treatment of hyperthyroidism

objective  To determine the cumulative incidence of hypothyroidism during long‐term follow‐up in patients treated for hyperthyroidism by radioactive iodine 131I (RAI) therapy, the significance of clinical factors in predicting the development of hypothyroidism, and the outcome after a fixed 7 mCi (259 MBq) dose of RAI.

Increased cancer incidence after radioiodine treatment for hyperthyroidism

Concerns remain about risk of cancer after radioactive iodine (RAI) treatment for hyperthyroidism, especially in organs that concentrate iodine. The objective was to assess the long‐term cancer risk from RAI treatment for hyperthyroidism.

Gluten-free diet and autoimmune thyroiditis in patients with celiac disease. A prospective controlled study.

Abstract Objective. Early diagnosis and dietary treatment with a gluten-free diet might slow down the progression of associated autoimmune diseases in celiac disease, but the data are contradictory. We investigated the course of autoimmune thyroid diseases in newly diagnosed celiac disease patients before and after gluten-free dietary treatment. Material and methods. Twenty-seven consecutive adults with newly diagnosed celiac disease were investigated at the time of diagnosis and after 1 year on gluten-free diet. Earlier diagnosed and subclinical autoimmune thyroid diseases were recorded and examined. Thyroid gland volume and echogenicity were measured by ultrasound. Autoantibodies against celiac disease and thyroiditis, and thyroid function tests were determined. For comparison, 27 non-celiac controls on normal gluten-containing diet were examined. Results. At the time of diagnosis, the celiac disease patients had more manifest (n = 7) or subclinical (n = 3) thyroid diseases than the controls (10/27 vs. 3/27, p = 0.055). During the follow-up, the thyroid volume decreased significantly in the patients with celiac disease compared with the controls, indicating the progression of thyroid gland atrophy despite the gluten-free diet. Conclusions. Celiac patients had an increased risk of thyroid autoimmune disorders. A gluten-free diet seemed not to prevent the progression of autoimmune process during a follow-up of 1 year.

Increased long‐term cardiovascular morbidity among patients treated with radioactive iodine for hyperthyroidism

Objective  Previous studies suggest that hyperthyroid patients remain at increased risk of cardiovascular morbidity after restoring euthyroidism. The aim of this study was to compare the rate and causes of hospitalization of hyperthyroid patients treated with radioactive iodine (RAI) with those of an age‐ and gender‐matched reference population in a long‐term follow‐up study.

Interleukin-6 modulates plasma cholesterol and C-reactive protein concentrations in nonagenarians.

Objectives: To establish whether the relationship between interleukin‐6 (IL‐6) and plasma lipid and C‐reactive protein (CRP) concentrations is different in Finnish nonagenarians than in middle‐aged subjects with lower inflammatory status.

Circulating oxidized low-density lipoprotein and common carotid artery intima-media thickness in a random sample of middle-aged men

Circulating oxidized low-density lipoprotein (oxLDL) has been suggested to play an important role in atherosclerosis development. According to previous observations, oxLDL correlates with clinically manifest coronary and carotid artery disease. We investigated the association between the oxLDL concentration measured directly in plasma and common carotid artery intima-media thickness (IMT) in a population-based, case-control study in middle-aged men from Southern Finland. oxLDL was determined in 214 men by a commercially available sandwich ELISA test (Mercodia). Carotid artery IMT was measured at 12 standardized segments by B-mode ultrasonography (at the near and far wall of the left and right common carotid arteries, bifurcations and internal carotid arteries), and the overall mean maximum IMT (MMaxIMT) was calculated. The MMaxIMT of the carotid arteries was significantly associated with circulating oxLDL (r(s) = 0.16, p = 0.018). In a stepwise multiple regression model with MMaxIMT as dependent variable and systolic blood pressure, smoking, oxLDL, HDL cholesterol and apolipoprotein B as covariates, systolic blood pressure (beta = 0.22, p < 0.001), oxLDL (beta = 0.15, p = 0.022) and smoking (beta = 0.17, p = 0.014) showed an independent association with IMT (R(2) = 0.10, p < 0.001). Our results show that oxLDL measured directly from plasma is independently associated with subclinical carotid artery atherosclerosis in middle-aged men.

Cardiovascular morbidity and mortality in surgically treated hyperthyroidism – a nation-wide cohort study with a long-term follow-up

Previous studies suggest that patients with hyperthyroidism remain at an increased risk of cardiovascular morbidity even after restoring euthyroidism. The mechanisms of the increased risk and its dependency on the different treatment modalities of hyperthyroidism remain unclear. The aim of this long‐term follow‐up study was to compare the rate of hospitalizations for cardiovascular causes and the mortality in hyperthyroid patients treated surgically with an age‐ and gender‐matched reference population.

Cancer Incidence and Mortality in Patients Treated Either With RAI or Thyroidectomy for Hyperthyroidism.

CONTEXT Some previous studies have suggested increased cancer risk in hyperthyroid patients treated with radioactive iodine (RAI). It is unclear whether the excess cancer risk is attributable to hyperthyroidism, its treatment, or the shared risk factors of the two diseases. OBJECTIVE The objective was to assess cancer morbidity and mortality in hyperthyroid patients treated with either RAI or surgery. PATIENTS We identified 4334 patients treated surgically for hyperthyroidism in Finland during 1986-2007 from the Hospital Discharge Registry and 1814 patients treated with RAI for hyperthyroidism at Tampere University Hospital. For each patient, three age- and gender-matched controls were chosen. Information on cancer diagnoses was obtained from the Cancer Registry. The follow-up began 3 months after the treatment and ended at cancer diagnosis, death, emigration, or the common closing date (December 31, 2009). RESULTS The overall cancer incidence was not increased among the hyperthyroid patients compared to their controls (rate ratio [RR], 1.05; 95% confidence interval [CI], 0.96-1.15). However, the risk of cancers of the respiratory tract (RR, 1.46; 95% CI, 1.05-2.02) and the stomach (RR, 1.64; 95% CI, 1.01-2.68) was increased among the patients. The overall cancer mortality did not differ between the patients and the controls (RR, 1.08; 95% CI, 0.94-1.25). The type of treatment did not affect the overall risk of cancer (hazard ratio for RAI vs thyroidectomy, 1.03; 95% CI, 0.86-1.23) or cancer mortality (hazard ratio, 1.04; 95% CI, 0.91-1.21). CONCLUSIONS In this cohort of Finnish patients with hyperthyroidism treated with thyroidectomy or RAI, the overall risk of cancer was not increased, although an increased risk of gastric and respiratory tract cancers was seen in hyperthyroid patients. Based on this large-scale, long-term follow-up study, the increased cancer risk in hyperthyroid patients is attributable to hyperthyroidism and shared risk factors, not the treatment modality.

HDL enhances oxidation of LDL in vitro in both men and women

BackgroundOxidative modification of low-density lipoprotein (LDL) is a key event in the oxidation hypothesis of atherogenesis. Some in vitro experiments have previously suggested that high-density lipoprotein (HDL) co-incubated with LDL prevents Cu2+-induced oxidation of LDL, while some other studies have observed an opposite effect. To comprehensively clarify the role of HDL in this context, we isolated LDL, HDL2 and HDL3 from sera of 61 free-living individuals (33 women and 28 men).ResultsWhen the isolated LDL was subjected to Cu2+-induced oxidation, both HDL2 and HDL3 particles increased the rate of appearance and the final concentration of conjugated dienes similarly in both genders. Oxidation rate was positively associated with polyunsaturated fatty acid content of the lipoproteins in that it was positively related to the content of linoleate and negatively related to oleate. More saturated fats thus protected the lipoproteins from damage.ConclusionWe conclude that in vitro HDL does not protect LDL from oxidation, but is in fact oxidized fastest of all lipoproteins due to its fatty acid composition, which is oxidation promoting.

A nationwide study on parathyroid carcinoma

Abstract Background: Parathyroid carcinoma (PC) is rare and diagnostically challenging. Reported outcomes are rather poor and the incidence might be increasing. Material and methods: We performed a nationwide study on all cases (n= 32) diagnosed in 2000–2011 in Finland, and compared clinical and histopathological characteristics and outcome to atypical parathyroid (APA; n= 28) and parathyroid adenomas (PA; n= 72). The incidence in years 1955–1999 was compared to that in 2000–2013. Results: Preoperatively, calcium and parathyroid hormone concentrations were higher in PC compared to APA and PA (1.76, 1.56 and 1.44 mmol/l, p < .001; and 989, 355 and 160 μmol/l, p < .001, respectively). Calcium was ≤1.77 mmol/l for all PAs. Hospitalization (44% vs. 22% and 3%, respectively, p = .01), renal (50% vs. 48% vs. 22%, respectively, p = .01) and bone (47% vs. 15% vs. 38%, respectively p = .002) manifestations were more common. PC and APA tumors were larger than PA (p < .001). Histopathological characteristics of PC compared to PA are increased mitotic activity (p= .001), chief cells (p = .003), diffuse growth pattern (p < .001), higher Ki67 (p< .001) and negative parafibromin (p < .001). One PC (1/18) and one APA (1/16) patient had a CDC73 mutation. After 6.7 (2–13.9) years of follow-up, 9.4% of PC had residual, 21% recurrent disease and 12.5% died of disease. Overall mortality did not differ between subgroups (p = .094). Recurrent PC was characterized by vascular invasion, lymph node metastases, high mitotic activity, necrosis and negative parafibromin. Incidence increased from 1.42 (range 0.52–2.14) to 7.14 (range 3.42–10.38)/10.000.000/years; (p < .001). Conclusions: PC associates with severe primary hyperparathyroidism and must be suspected if calcium ≥1.77 mmol/l. The prevalence of CDC73 germline mutations in PC and APA in Finland is 6%. PC has distinct histopathological characteristics and its incidence has increased over the past decades.