Introduction: The incidence of stroke among both young and older adults is on the rise, with cardiovascular risk factors playing a key role in its occurrence. Cardiac conditions can act as either predisposing factors or consequences of stroke. The distribution of cardiovascular and cerebrovascular risk factors across age groups may influence electrocardiographic (ECG) findings in stroke patients.

Objective: This study aimed to assess and compare the prevalence and pattern of ECG abnormalities among young (<45 years) and older (≥45 years) stroke patients, considering various stroke subtypes.

Methodology: A cross-sectional comparative study involving 180 participants—90 young and 90 older adults diagnosed with stroke—was carried out at DELSUTH, Nigeria. Each participant underwent electrocardiography, and ECG findings were analyzed across age groups using chi-square and t-tests.

Results: The mean age was 40.23 ± 2.75 for young and 65.77 ± 12.34 years for older participants. The male-to-female ratio was 1.4:1 and 1.6:1, respectively. Ischaemic stroke was the dominant subtype (54.4% in young; 68.9% in older patients). Haemorrhagic types (intracerebral and subarachnoid) were more common in younger patients (45.6%) than in older patients (31.1%), showing statistical significance (p = 0.046).

Electrocardiographic left ventricular hypertrophy (LVH) was the most frequent abnormality in both age groups based on both Sokolow-Lyon and Araoye’s criteria. ST segment/T wave changes followed closely with no significant age-related differences. However, rhythm disorders were significantly more prevalent among older adults (51.1% vs. 14.4%; p < 0.001). Atrial fibrillation appeared more frequently in the older group (10%) but without statistical significance.

Conclusion: While many ECG abnormalities did not differ significantly between age groups, rhythm disorders were more common in older adults. Routine ECG evaluation is recommended for all stroke patients regardless of age.