Symptoms of Anemia
Common symptoms of anemia include fatigue, weakness, exercise dyspnea, headache, vertigo, chest pain, syncope, pallor, and abnormal menstruation in females. 1 These symptoms result from decreased oxygen-carrying capacity and can significantly impact quality of life.
Cardinal Symptoms
- Fatigue and weakness: Most common symptoms, described as a "distressing persistent subjective sense of tiredness or exhaustion that is not proportional to recent activity and interferes with normal functioning" 1
- Dyspnea on exertion: Shortness of breath during physical activity
- Headache and vertigo: Due to cerebral hypoxia
- Chest pain: May occur especially in patients with underlying cardiovascular disease
- Syncope: Fainting or near-fainting episodes
- Pallor: Visible paleness of skin, conjunctiva, and mucous membranes
Additional Symptoms
- Pica: Craving for non-nutritive substances (occurs in 40-50% of iron deficiency cases) 2
- Restless legs syndrome: Uncomfortable sensations in legs with urge to move them (occurs in 32-40% of iron deficiency cases) 2
- Cognitive impairment: Difficulty concentrating, irritability, depression 2
- Cold skin: Due to peripheral vasoconstriction 3
- Palpitations: Awareness of rapid or irregular heartbeat
- Tachycardia: Compensatory mechanism to maintain oxygen delivery
Severity Factors
The severity of symptoms depends on:
- Degree of anemia: More severe with lower hemoglobin levels
- Rapidity of onset: Acute anemia causes more pronounced symptoms than chronic anemia
- Age and physiologic status: Elderly patients and those with comorbidities may experience symptoms at higher hemoglobin levels 4
Special Considerations
Elderly Patients
Older adults may present with:
- Worsening of existing cardiovascular disease: Heart failure exacerbation
- Cognitive dysfunction: Confusion or worsening dementia
- Falls: Due to weakness and dizziness
- Functional decline: Reduced ability to perform activities of daily living 4
Patients with Heart Failure
- Worsening heart failure symptoms: Increased dyspnea, edema
- Reduced exercise tolerance: Even with mild anemia
- Increased hospitalization risk: Anemia is associated with poorer outcomes 5
Cancer Patients
- Exacerbation of fatigue: Beyond what is expected from the malignancy itself
- Reduced quality of life: Significant impact on daily functioning
- Potential reduced treatment efficacy: May affect response to therapy 1, 3
Warning Signs Requiring Urgent Evaluation
- Severe dyspnea at rest: May indicate critical anemia
- Chest pain: Particularly in patients with coronary artery disease
- Syncope: Especially with minimal exertion
- Signs of active bleeding: Hematemesis, melena, hematochezia
- Hemodynamic instability: Tachycardia, hypotension
Clinical Pearls
- Anemia may be asymptomatic and discovered incidentally on laboratory testing, especially in chronic, slowly developing cases 4
- Symptoms often correlate poorly with hemoglobin levels due to compensatory mechanisms
- Cancer-related fatigue differs from normal fatigue as it is less likely to be ameliorated by rest 1
- Iron deficiency without anemia can cause symptoms like fatigue, cognitive impairment, and restless legs syndrome 2
- Clinicians should be aware of signs of underlying causes, such as jaundice, splenic enlargement, neurologic symptoms, blood in stool, petechiae, and heart murmur 1
Remember that symptoms of anemia are neither sensitive nor specific to the type of anemia, and further laboratory evaluation is necessary to determine the underlying cause and guide appropriate treatment.