Blood Pressure Measurement in Diabetes Clinic

Are we paying enough attention?

The American Diabetes Association statement (1), “Care of Children and Adolescents With Type 1 Diabetes,” outlines recommendations for management of hypertension in children with type 1 diabetes. Hypertension in children can be missed if appropriate norms are not used, and, as the authors state, “clinicians who care for children with diabetes often pay little or no attention to blood pressure.” Here, we report results of a retrospective chart review of serial clinic blood pressure measurements among 217 youth with type 1 diabetes for ≥5 years. Hypertension was defined as systolic and/or diastolic blood pressure >95th percentile for age, sex, and height at three consecutive clinic visits (2). Blood pressure was taken at each outpatient visit using an automated blood pressure device by trained medical assistants.

Sixty (28%) of 217 patients met the study diagnosis of hypertension (mean age 12.7 ± 3.2 years) after 5.7 ± 3.8 years of diabetes. These patients had higher systolic blood pressure z-scores (1.13 vs. 0.49, P = 0.002) and higher BMI z-scores (0.68 vs. 0.30, P = 0.01) at the time of diabetes diagnosis than did patients without hypertension. Only 21 of 60 (35%) had the diagnosis documented in the medical chart, and only 5 of 60 patients (8.3%) had therapy initiated specifically for treatment of hypertension. Spot-urinary albumin-to-creatinine ratios were categorized as normal (<20 μg/mg), high normal (≥20 but <30 μg/mg on two of three measurements), and microalbuminuria (≥30 μg/mg on two of three measurements). Seventeen (9%) of those with available data (n = 190) had microalbuminuria. This complication was more frequently addressed than hypertension, with 14 of 17 (82%) subjects being treated with ACE inhibitors. Patients who met study criteria for hypertension tended to have higher albumin-to-creatinine ratios. Of those patients with available data, 2 of 57 (4%) with elevated blood pressures had high-normal ratios and 8 of 57 (14%) developed microalbuminuria, while 0 of 133 with normal blood pressure had high-normal ratios and 9 of 133 (7%) developed microalbuminuria (P for trend <0.05).

Our analysis is retrospective and relies upon casual blood pressures, which may overestimate the true rate of hypertension. Nonetheless, our data indicate that adolescents with type 1 diabetes may develop blood pressure in the hypertensive range, and as suggested by the recent American Diabetes Association statement, this blood pressure may not be routinely recognized. This represents missed opportunities to confirm hypertension with repeat ausculatory measurement and/or 24-h ambulatory blood pressure monitoring and to intervene with lifestyle modification/pharmacologic therapy, all with the hope of preventing future micro- and macrovascular complications. Routine blood pressure assessment using appropriate age-, sex-, and height-dependent norms is an essential component of every visit to the diabetes clinic.