Seasonal variation in the diagnosis of Graves' disease

Priority focus areas for a sub-national response to climate change and health: A South African provincial case study

INTRODUCTION

The intersection of health and climate change is often absent or under-represented in sub-national government strategies. This analysis of the literature, using a new methodological framework, highlights priority focus areas for a sub-national government response to health and climate change, using the Western Cape (WC) province of South Africa as a case study.

METHODS

A methodological framework was created to conduct a review of priority focus areas relevant for sub-national governments. The framework encompassed the establishment of a Project Steering Group consisting of relevant, sub-national stakeholders (e.g. provincial officials, public and environmental health specialists and academics); an analysis of local climatic projections as well as an analysis of global, national and sub-national health risk factors and impacts.

RESULTS

Globally, the discussion of health and climate change adaptation strategies in sub-national, or provincial government is often limited. For the case study presented, multiple health risk factors were identified. WC climatic projections include a warmer and potentially drier future with an increased frequency and intensity of extreme weather events. WC government priority focus areas requiring further research on health risk factors include: population migration and environmental refugees, land use change, violence and human conflict and vulnerable groups. WC government priority focus areas for further research on health impacts include: mental ill-health, non-communicable diseases, injuries, poisonings (e.g. pesticides), food and nutrition insecurity-related diseases, water- and food-borne diseases and reproductive health. These areas are currently under-addressed, or not addressed at all, in the current provincial climate change strategy.

CONCLUSIONS

Sub-national government adaptation strategies often display limited discussion on the health and climate change intersect. The methodological framework presented in this case study can be globally utilized by other sub-national governments for decision-making and development of climate change and health adaptation strategies. Additionally, due to the broad range of sectoral issues identified, a primary recommendation from this study is that sub-national governments internationally should consider a "health and climate change in all policies" approach when developing adaptation and mitigation strategies to address climate change.

Incidence of hyperthyroidism in Sweden

INTRODUCTION

The incidence of hyperthyroidism has been reported in various countries to be 23-93/100,000 inhabitants per year. This extended study has evaluated the incidence for ~40% of the Swedish population of 9 million inhabitants. Sweden is considered to be iodine sufficient country.

METHODS

All patients including children, who were newly diagnosed with overt hyperthyroidism in the years 2003-2005, were prospectively registered in a multicenter study. The inclusion criteria are as follows: clinical symptoms and/or signs of hyperthyroidism with plasma TSH concentration below 0.2 mIE/l and increased plasma levels of free/total triiodothyronine and/or free/total thyroxine. Patients with relapse of hyperthyroidism or thyroiditis were not included. The diagnosis of Graves' disease (GD), toxic multinodular goiter (TMNG) and solitary toxic adenoma (STA), smoking, initial treatment, occurrence of thyroid-associated eye symptoms/signs, and demographic data were registered.

RESULTS

A total of 2916 patients were diagnosed with de novo hyperthyroidism showing the total incidence of 27.6/100,000 inhabitants per year. The incidence of GD was 21.0/100,000 and toxic nodular goiter (TNG=STA+TMNG) occurred in 692 patients, corresponding to an annual incidence of 6.5/100,000. The incidence was higher in women compared with men (4.2:1). Seventy-five percent of the patients were diagnosed with GD, in whom thyroid-associated eye symptoms/signs occurred during diagnosis in every fifth patient. Geographical differences were observed.

CONCLUSION

The incidence of hyperthyroidism in Sweden is in a lower range compared with international reports. Seventy-five percent of patients with hyperthyroidism had GD and 20% of them had thyroid-associated eye symptoms/signs during diagnosis. The observed geographical differences require further studies.

Incidence of thyrotoxicosis in childhood: a national population based study in the UK and Ireland

OBJECTIVE

To measure the UK and Ireland incidence of childhood (<15 years) thyrotoxicosis and to describe the presenting features.

CONTEXT

Incidence data on thyrotoxicosis in childhood are not available for the UK and Ireland. Recent studies have reported an apparent increase in cases in Europe.

DESIGN

A national prospective surveillance study for 12 months from September 2004, co-ordinated by The British Paediatric Surveillance Unit (BPSU).

PATIENTS AND MEASUREMENTS

All paediatricians across the UK and Ireland were requested monthly to report new cases. Details of presenting features were then obtained by questionnaire.

RESULTS

One hundred ten cases of acquired childhood thyrotoxicosis were identified in the UK and Ireland. The incidence of acquired thyrotoxicosis was 0.9 per 100,000 <15 years olds in the UK and Ireland, (95% CI: 0.8-1.1). Autoimmune thyrotoxicosis accounted for 96% of cases. There was an increasing incidence with age in each sex. Females have a significantly higher incidence than males in the 10- to 14-year age group. A variety of presenting symptoms were reported: weight loss (64%), fatigue/tiredness (54%), change in behaviour' (50%) and heat intolerance (47%). 4.5 % cases were asymptomatic. The commonest signs were goitre (78%) and tremor (58%). There were no cases of thyroid storm.

CONCLUSIONS

This national population survey defines the incidence of thyrotoxicosis in children in the UK and Ireland during 2004-2005, which was lower than expected in comparison with other European studies. The survey illustrates contemporary presenting characteristics of the disease.

Seasonal variation in relapse rate of graves' disease after thionamide drug treatment

OBJECTIVE

Controversy abounds on the issue of seasonal variation in new onset of Graves' disease, partly due to the difficulty of precisely dating the exact start of symptoms. To address the possible relationship between climatic changes and disease activity from a different perspective, we reviewed time of relapse during regular follow-up after successful drug treatment with thionamides.

DESIGN

Retrospective analysis of a case series in a university clinic.

PATIENTS AND MEASUREMENTS

We consecutively registered patients who experienced re-emergence of hyperthyroidism between 1992 and 2001 after successful antithyroid drug therapy. Excluded were subjects with superimposing painless thyroiditis, in postpartum, on immunomodulatory drugs, or off thionamides prematurely on their own volition.

RESULTS

Fifty-two patients recurred 2 to 36 months after drug cessation. The frequency was higher in spring and summer (March to August) than in autumn and winter (September to February). With a new coated-tube radioreceptor assay, TSH binding inhibitor immunoglobulin activity was detected in sera from 87.5% of the reworsened patients.

CONCLUSIONS

Graves' disease tends to relapse more frequently in spring and summer. Further clinical studies are warranted to clarify underlying mechanism (s) for this seasonal variation.

Absence of seasonal variation in Graves disease

PURPOSE

To determine whether there is an identifiable pattern of seasonal variation in the onset of symptoms of orbitopathy and thyrotoxicosis in patients with Graves disease.

METHODS

This retrospective, noncomparative case series reviewed 305 randomly selected office records of patients referred to one author (M.K.) for evaluation of Graves orbitopathy between July 1990 and June 1998. All patients met inclusion criteria for the diagnosis of Graves orbitopathy. During initial evaluation for orbitopathy, patients identified the date of onset of orbital symptoms as well as the earliest date of either onset of thyroid symptoms or documented thyroid abnormality. Patients were excluded from analysis of seasonal variation if they could not recall the month of symptom onset or were euthyroid. The onset of orbital symptoms and identification of dysthyroid state were analyzed by calendar month and season. The chronological relationship of the development of orbital and thyroid symptoms was evaluated.

RESULTS

No significant seasonal variation appeared in the onset of orbital symptoms or identification of dysthyroidism. Out of 148 patients, 115 (78%) developed symptoms of orbital disease within 18 months of the identification of dysthyroidism. The most common presenting orbital symptoms were swelling of the lid or prominence of the globe.

CONCLUSIONS

This study fails to provide evidence for a seasonal influence on the incidence of Graves disease and the associated orbitopathy.

Chronology of Graves' ophthalmopathy in an incidence cohort

PURPOSE

To determine the chronologic characteristics of Graves' ophthalmopathy in an incidence cohort of 120 patients.

METHODS

We reviewed the community medical records of 120 patients residing in Olmsted County, Minnesota, in whom Graves' ophthalmopathy had been diagnosed between 1976 and 1990.

RESULTS

Median age at the time of diagnosis of Graves' ophthalmopathy was 43 years; the minimum and maximum ages were 8 and 88 years, respectively. Among 108 patients with hyperthyroidism, ophthalmopathy was diagnosed in the six-month interval preceding the diagnosis of thyroid dysfunction in 20 patients (18.5%); ophthalmopathy was concurrent with the diagnosis of hyperthyroidism in 22 patients (20.3%); and ophthalmopathy developed in the six-month interval after thyroid diagnosis in 24 patients (22.2%). Ophthalmopathy was diagnosed more than six months before the diagnosis of hyperthyroidism in only four additional patients (3.7%), whereas ocular changes developed six months or more after thyroid disease in the remaining 38 patients (35.2%). There was no significant seasonal variation in the diagnosis of either thyroid dysfunction or ophthalmopathy. Treatment of hyperthyroidism with iodine-131 did not appear to influence the course of Graves' ophthalmopathy.

CONCLUSIONS

There is a strong temporal relationship between the thyroid and eye manifestations of Graves' disease. The diagnosis of Graves' ophthalmopathy tends to follow the diagnosis of hyperthyroidism. Treatment with iodine-131 does not appear to influence the course of Graves' ophthalmopathy. Although both childhood Graves' disease and Graves' ophthalmopathy are uncommon, ophthalmopathy occurs at all ages.