Hi and welcome,
"Until relatively recently, WMH were generally dismissed as inevitable consequences of “normal” advancing age. This is clearly not true. Although WMH do become more common with advancing age, their prevalence is highly variable.
There is strong evidence that WMH are clinically important markers of increased risk of stroke, dementia, death, depression, impaired gait, and mobility, in cross-sectional and in longitudinal studies. They associate with brain damage such as global atrophy and other features of small vessel brain damage, with focal progressive visible brain damage, are markers of underlying subvisible diffuse brain damage, and predict infarct growth and worse outcome after large artery stroke. They could be considered as the neuroimaging marker of brain frailty." (Wardlaw et al., 2015)
What your brain MRI has found though isn't significant or out side normal expectations for basically any age group, your MRI only showed a single non specific white matter hyperintensity (lesion) - which is likely to be very tiny if your report doesn't also include it's size, usually only 1-3 mm lesions are unmeasured on MRI reports - and they are typically silent micro vascular related so what ever prompted you to get the brain MRI is more likely to be related to an abnormal brain related neurological condition.
Hope that helps.....JJ