Patients with hypertension who develop new-onset declines in kidney function are at increased risk of death from heart disease, according to an article in the June issue of the Journal of the American Society of Nephrology.

Dr. Julian Segura and his Spanish colleagues performed a long-term follow-up study of 281 patients with hypertension who had baseline normal kidney function. When the patients were re-evaluated an average of 13 years later, about 15 percent had moderately reduced kidney function.

Roughly 17 percent of patients had some type of cardiovascular event during the follow-up period. Cardiovascular events affected 41 percent of the patients who had developed kidney disease compared with 13 percent of those whose kidney function had remained normal.

Several factors increased the risk of developing kidney disease, including a lower initial level of kidney function, older age, higher cholesterol level, and higher blood pressure. At the start of the study, average blood pressure was 182/112 mm Hg for patients who developed kidney disease during follow-up compared with 161/102 mm Hg for patients who retained normal kidney function.

After adjustment for other risk factors, the risk of heart disease or stroke was about 2.5 times higher for patients who developed kidney disease. Older patients and men were also at higher risk of cardiovascular events.

Patients who took an angiotensin converting enzyme inhibitor had a lower rate of heart disease or stroke. However, this preventive effect was significant only for patients with diabetes. More research is needed to confirm and extend the findings on hypertension, development of chronic kidney disease, and cardiovascular risk, as well as to identify treatments that may reduce risk for development of kidney disease in patients with hypertension.