To elucidate the association between high-density lipoprotein (HDL, “good”) cholesterol and the risk of heart attack and stroke among patients with type-2 diabetes, Gregory Nichols, from   Kaiser Permanente (Oregon, USA), and colleagues conducted a retrospective observational study of 30,067 patients who entered Kaiser Permanente diabetes registries in Oregon, Washington and Georgia between 2001 and 2006. These patients had at least two HDL cholesterol measurements between 6 and 24 months apart. Most patients (61 percent) had no significant change in HDL levels; in 22% of patients, HDL levels increased by at least 6.5 mg/dl (milligrams per deciliter of blood); in 17% of patients, HDL levels decreased by at least that same amount. After obtaining the cholesterol measurement, researchers followed the patients for up to 8 years to see if they were hospitalized for a heart attack or stroke. Patients whose HDL levels increased had 8% fewer heart attacks and strokes than patients whose HDL levels remained the same, while patients whose HDL levels decreased had 11% more heart attacks and strokes. The researchers observe that: “Our results add to the growing body of evidence that increasing the HDL cholesterol levels might be an important strategy for [cardiovascular disease] risk.”`