What are the signs and symptoms of hyperthyroidism, particularly in women with a family history of thyroid disease?

Signs and Symptoms of Hyperthyroidism

Hyperthyroidism presents with a constellation of hypermetabolic symptoms including tremors, nervousness, insomnia, excessive sweating, heat intolerance, tachycardia, hypertension, and goiter, with women having a family history of thyroid disease at increased risk for developing this condition. 1

Classic Hypermetabolic Symptoms

The most common presenting symptoms reflect the body's hypermetabolic state:

• Weakness and fatigue are among the most frequent complaints, affecting the majority of patients 2
• Palpitations and tachycardia occur due to increased cardiac output and heart rate 1, 2
• Unintentional weight loss despite normal or increased appetite is characteristic 3, 2
• Heat intolerance and excessive sweating result from increased metabolic rate 1, 2
• Tremor, particularly a fine tremor of the hands, is a common physical finding 2

Neuropsychiatric Manifestations

• Nervousness and anxiety are prominent features of thyrotoxicosis 1
• Insomnia frequently accompanies the hyperadrenergic state 1
• Muscle weakness, particularly in proximal muscle groups, is a common physical finding 2

Cardiovascular Signs

• Tachycardia is one of the most consistent physical findings on examination 2
• Hypertension can develop as a cardiovascular manifestation 1, 4
• Atrial fibrillation may occur, particularly in older patients with untreated hyperthyroidism 3

Gastrointestinal Symptoms

• Diarrhea or increased bowel movements result from accelerated gastrointestinal motility 3

Thyroid Gland Examination Findings

• Palpable goiter (enlarged thyroid gland) is frequently present on physical examination 2
• Diffusely enlarged thyroid gland is characteristic of Graves disease 3

Graves Disease-Specific Manifestations

When hyperthyroidism is caused by Graves disease (the most common etiology, affecting 2% of women and 0.5% of men globally), additional distinctive features appear:

• Thyroid eye disease including eyelid lag or retraction is pathognomonic for Graves disease 1, 3, 2
• Exophthalmos (bulging eyes) or stare may be present 3
• Pretibial myxedema (localized dermal thickening) is a distinctive dermal sign 1

Toxic Nodular Goiter-Specific Symptoms

When hyperthyroidism results from toxic multinodular goiter or toxic adenoma, patients may experience:

• Dysphagia (difficulty swallowing) from local compression 3
• Orthopnea (difficulty breathing when lying flat) from tracheal compression 3
• Voice changes from recurrent laryngeal nerve compression 3

Severe Presentation: Thyroid Storm

Thyroid storm is a rare but life-threatening medical emergency characterized by severe acute exacerbation of all hyperthyroid signs and symptoms, affecting less than 1% of pregnant women with hyperthyroidism. 1, 4

Risk Factors and Epidemiology

• Family history of thyroid disease increases the likelihood of developing hyperthyroidism 1
• Female sex confers higher risk, with Graves disease affecting women 4 times more frequently than men 3
• Subclinical hyperthyroidism (suppressed TSH with normal thyroid hormones) is more common in women than men, in blacks than whites, and in the elderly 1

Diagnostic Confirmation

• Suppressed TSH (typically <0.1 mIU/L) with elevated free T4 and/or T3 confirms overt hyperthyroidism 1, 3
• Low TSH with normal free T4 and T3 defines subclinical hyperthyroidism 1, 3
• Thyrotropin receptor antibodies are present in Graves disease and have 97.4% sensitivity and 99.2% specificity 5

Critical Complications of Untreated Hyperthyroidism

• Cardiac arrhythmias and heart failure can develop without treatment 3
• Osteoporosis results from accelerated bone turnover 3
• Adverse pregnancy outcomes including preeclampsia, preterm delivery, and low birth weight occur in pregnant women 1
• Increased mortality is associated with untreated hyperthyroidism 3

Common Pitfalls

A critical pitfall is failing to recognize atypical presentations in elderly patients, where apathetic hyperthyroidism may present with fatigue rather than classic hypermetabolic symptoms 6. Additionally, subclinical hyperthyroidism may be asymptomatic but still carries cardiovascular and bone risks, particularly in those over 65 years or with TSH <0.1 mIU/L 1, 3.