Which patient is most at risk for hypoglycemia in type 1 diabetes mellitus?

The patient who is most at risk for hypoglycemia in type 1 diabetes mellitus is the athlete increasing exercise duration. In type 1 diabetes, the regulation of blood glucose levels relies heavily on the administration of exogenous insulin and careful monitoring of carbohydrate intake, especially around periods of increased activity.

Exercise enhances insulin sensitivity and accelerates glucose uptake by the muscles. As an athlete increases their exercise duration or intensity, they may require adjustments to their insulin regimen or carbohydrate intake to prevent hypoglycemia. If they do not compensate for the increased energy expenditure or adjust insulin appropriately, the risk of having low blood sugar levels increases.

While other situations can pose risks, they do not have the same direct impact on blood glucose regulation during physical activity. For instance, a recent respiratory infection could cause stress and affect metabolic control but is less predictable in terms of its impact on hypoglycemia risk compared to exercise. A minor skin infection might not significantly alter insulin sensitivity or metabolism as dramatically as exercise can, and prednisone, a corticosteroid, is more likely to raise blood glucose levels rather than lower them, thus decreasing the risk of hypoglycemia. Therefore, the athlete increasing exercise duration clearly stands out as the primary concern regarding hypoglycemia in this context.