Background In this cross-sectional study conducted in Wakiso, Uganda, from May to July 2023, we investigated the interactions among age, sex, education, and heart rate in relation to dementia and Mild Cognitive Impairment (MCI) among individuals aged 65 years and older. Methods We purposively sampled 106 participants, focusing on those with Alzheimer’s disease and related dementias, leveraging collaborations with local health teams. Data collection involved comprehensive questionnaires covering sociodemographic details and health parameters, and employed the Montreal Cognitive Assessment Tool for dementia screening. Results Our findings highlight a nuanced landscape of risk factors; each additional year of age was associated with a 1.19- and 1.22-times increased risk of MCI and dementia, respectively. Gender analysis revealed a protective effect against MCI in males, but no significant impact on dementia risk. Education emerged as a protective factor, with each additional year associated with a 28% reduction in MCI risk, although its effect on dementia risk remains ambiguous. Significantly, an elevated heart rate was strongly linked to an increased risk of both MCI and dementia, underscoring the potential cardiovascular dimension in cognitive health. Conclusions This study contributes to the understanding of the complex interplay of risk factors for dementia, emphasizing the need for further research to elucidate the underlying mechanisms and interventions for healthy cognitive aging in the older adult population.