Stroke is a sudden disruption of blood circulation in the brain, often resulting in disability. Japanese scientists from Kobe University have presented unexpected data that may change the way we think about preventing the severe consequences of stroke. Published in Topics in Stroke Rehabilitation (TSR), the study of more than 522,000 patients found a surprising pattern: the optimal body mass index (BMI) for minimizing the risk of disability after stroke is not a skinny physique, but a value at the upper limit of normal.
The study was conducted using the modified Rankin Scale (mRS), which assesses the degree of disability in patients. Scientists analyzed the condition of patients both at admission to the hospital and at discharge, found out the dynamics of changes and their relationship with BMI. The results were striking: BMI of 24.7 kg/m² proved to be the most favorable for recovery after stroke. This index is on the edge of the upper limit of the norm (18.5-25 kg/m²), indicating some “protective” role of moderate overweight.
Moreover, the study revealed an alarming statistic: 60.1% of patients experienced a worsening of their condition during hospitalization, and 45.7% were discharged with a high mRS score, indicating significant disability. It was those with a BMI of about 24.7 kg/m², who were, one might say, “on the verge” of being overweight, who showed the most effective recovery.
Researchers emphasize a U-shaped relationship between BMI and stroke outcomes. This means that both underweight (underweight) and significantly overweight (obesity) increase the risk of severe disability after stroke. It turns out that extremes are harmful, while the golden mean, represented by a BMI of about 24.7 kg/m², can significantly reduce the likelihood of severe consequences.