The American Journal of Managed Care January 2010
New Diabetes HEDIS Blood Pressure Quality Measure: Potential for Overtreatment
The new HEDIS diabetes blood pressure measure may promote performance incentives for overtreatment of blood pressure, causing potential harm, especially in the elderly population.
Objective: To examine reasons for failing to meet the new Healthcare Effectiveness Data and Information Set (HEDIS) blood pressure (BP) measure for diabetes patients (BP <130/80 mm Hg), which may not accurately identify poor-quality care and could promote overtreatment through its performance incentives.
Study Design: Retrospective chart review.
Methods: We formed 2 cohorts of diabetes patients in 9 general medicine clinics in an academic healthcare system. Cohort A (n = 124) failed the new HEDIS measure but passed the old measure (systolic blood pressure [SBP] 130-139 and diastolic blood pressure [DBP] <90 mm Hg; or SBP <140 and DBP 80-89 mm Hg). Cohort B (n = 125) failed the old measure (SBP ≥140 and/ or DBP ≥90). We reviewed medical records to ascertain clinician response to elevated BP.
Results: Physicians documented treatment changes in only 4% and 28% of cohort A and B patients, respectively. Refractory systolic hypertension was common in those aged ≥65 years; 60% of those in cohort B and 58% in cohort A took 3 or more antihypertensive medications and/or had a diastolic BP below 70 mm Hg.
Conclusions: We identified a substantial cohort of elderly diabetes patients with DBP <70 mm Hg who were on 3 medications at adequate doses, but who did not meet the current performance measurement criteria (140/90 or 130/80 mm Hg). We suggest that such patients be excluded from performance measures, or if included, be noted for special attention by clinicians to balance intensification with risk.
(Am J Manag Care. 2010;16(1):19-24)
There are concerns that the new Healthcare Effectiveness Data and Information Set (HEDIS) diabetes blood pressure measure may not accurately identify poor-quality care and could promote overtreatment through its performance incentives.
- The new HEDIS blood pressure measure commonly mislabeled patients as being inadequately treated, especially elderly patients.
- New blood pressure measures should be developed to encourage aggressive treatment of hypertension without unduly promoting overtreatment.
Although there is near-universal agreement on the benefits of aggressive BP treatment for those with diabetes, the new HEDIS BP performance measure of <130/80 mm Hg for diabetes has generated considerable controversy. For example, this measure was adopted despite the objections of the Technical Expert Panel of the National Diabetes Quality Improvement Alliance.4 One concern about this quality measure was that unadjusted BPs may be an unreliable measure of quality, especially because the severity of patients’ hypertension and their age are known to greatly influence whether an SBP of <130 mm Hg is achievable.1-3 Although substantial research suggests that well-constructed process measures often show better quality in sicker patients,8 this is not always true of unadjusted outcome measures. Therefore, an unadjusted BP performance measure of <130/80 mm Hg would be expected to systematically penalize those caring for sicker and older patients. A second concern was that this measure could create performance incentives for overtreating refractory systolic hypertension, leading to potential patient harm from polypharmacy and pushing DBP substantially below 70 mm Hg.2,4,9
Because of the above concerns, the National Diabetes Quality Improvement Alliance’s Technical Expert Panel recommended that the new HEDIS BP performance measure of <130/80 mm Hg should exclude those patients requiring more than standard doses of 3 to 4 BP medications, as well as those patients whose DBPs are <70 mm Hg. However, not knowing which medications were permissible and having no dosing information made the medication exception infeasible.
We could find little evidence in the medical literature regarding how often the circumstances that are of concern with the new HEDIS criteria actually occur in a primary care diabetes population. Therefore, we examined BP levels and medication treatment intensity in patients with diabetes receiving primary care in a large academic healthcare system. We were interested in the circumstances surrounding those patients with diabetes who failed to meet the new HEDIS BP performance measure of <130/80 mm Hg (with special attention to those whose BP was <140/90 but not <130/80 mm Hg) and examined the proportion of patients (1) who already were on moderate doses of 3 or more BP medications (the maximum therapy examined in most clinical trials) and (2) who already had a DBP of <70 mm Hg (the flexion point in cohort studies at which CV mortality starts to substantially increase).2,9 In addition, we examined whether there were differences in the above factors between patients age 65 years and older compared with those younger than age 65 years, as older individuals are more prone to refractory systolic hypertension.
Study Design and Patient Population This is a retrospective, descriptive study of patients cared for in 9 general medicine outpatient clinics of a large academic healthcare system. The majority of clinics are located in community settings in which patients are cared for by fulltime clinicians. Adult patients were identified from a validated diabetes registry developed by our healthcare system, which includes more than 11,000 patients. Although the Diabetes Alliance Technical Expert Panel recommended that the BP measure only be applied to those with hypertension, the new HEDIS measure was applied to all patients with diabetes, mainly because of the difficulty in obtaining accurate information on which patients were previously diagnosed with hypertension. In addition, our population differed slightly from HEDIS specifications because HEDIS was developed for defined managed care populations and our registry includes all patients with diabetes regardless of insurance (eg, fee-for-service, managed care, Medicaid, Medicare). Therefore, we used an adaptation of the HEDIS denominator population specifications in our study. The registry includes all outpatient BP readings documented either in the vital signs component (which includes BP) of the health system electronic medical record’s vital signs, or from outpatient physician progress notes. We selected 2 patient cohorts for this study. Cohort A included patients with diabetes whose most recent BP did not meet the new HEDIS quality indicator of BP <130/80 mm Hg, but who would have been considered in compliance with the established HEDIS BP criterion of BP <140/90 mm Hg. These patients had either an SBP of 130 to 139 and a DBP of <90 mm Hg or an SBP of <140 and a DBP of 80 to 89 mm Hg. Cohort B included patients whose SBP was ≥140 and/or whose DBP was ≥90 mm Hg and thus did not meet the established HEDIS criterion for patients with diabetes.
We reviewed the electronic medical records of a randomly selected sample of 398 patients from the Diabetes Registry who met the inclusion criteria, 195 in cohort A and 203 in cohort B. Patients were excluded from the study (37 and 43 patients from cohorts A and B, respectively) if their most recent visit with an elevated BP was with a provider who does not routinely address hypertension (eg, an ophthalmologist, a podiatrist). Patients also were excluded (8 and 10 patients from cohorts A and B, respectively) if on full chart review the lowest BP reading recorded at the visit was <130/80 mm Hg or if the patient did not have diabetes. Consistent with HEDIS measurement criteria, patients over age 75 years were excluded (26 and 25 patients from cohorts A and B, respectively), leaving 124 patients in cohort A and 125 patients in cohort B. The study period was from June 2005 through November 2007. The study was approved by our institutional review board.
The review confirmed the diagnosis of diabetes and, beginning with the patient’s most recent clinic visit as the index visit, collected the following data from the chart review or the registry: age, sex, most recent BP measurement, glycosylated hemoglobin, low-density lipoprotein cholesterol, class and doses of antihypertensive medications, and physician response to the elevated BP (no change in BP medications, increase dose of BP medications, or start a new BP medication) as well as the reasoning behind the treatment decision. Data Analysis Descriptive analysis is presented by using means and standard deviations. Frequency data are presented by using count and percentage. To compare patients by age group, a t test (continuous data) or a X2 test (categorical data) was used. All analyses were performed with Stata, version 8.1 (StataCorp, College Station, TX).
Among patients in the diabetes registry, 44% met the new HEDIS BP criteria of <130/80 mm Hg and were excluded from this study. The clinical characteristics of the patients with diabetes who did not meet the established and new HEDIS BP performance measures are summarized in Table 1. The patients’ mean age was 58 years, and 51% were male. More than half the patients seen in these clinics met the HEDIS performance measure for glycosylated hemoglobin (<7%), and three-fifths met the HEDIS performance measure for low-density lipoprotein (<100 mg/dL). Overall, the age distribution and HEDIS measures were similar to those of other high-performing health systems reported in the literature.10
Blood pressures and medications for those not at recommended BP goals are summarized in Table 2. Among cohort A patients (those meeting the established HEDIS criteria but not the new tight control criteria), 72% were on an antihypertensive medication. Among cohort B patients, who had an elevated BP defined as an SBP of ≥140 and/or a DBP of ≥90 mm Hg, 84% were on at least 1 antihypertensive medication and 31% were on 3 or more antihypertensive medications. Across both cohorts, the most commonly prescribed initial medication was an angiotensin-converting enzyme inhibitor (ACEI) or angiotensin II receptor blocker (ARB). Among patients on at least 2 antihypertensive medications, more than 90% were on an ACEI or ARB and three-quarters were on a thiazide diuretic, and low and subtherapeutic doses were extremely rare in those not at goal.
For patients with elevated BPs, physicians made and documented treatment changes in 4% and 28% of the patients in cohorts A and B, respectively. During routine follow-up patient visits at which no therapeutic changes were made or documented, the most common reason noted in the medical record was that the physician was satisfied with the BP control (17%), but in a large number of records the clinician did not address the high BP at the visit (46%).
There were significant differences between those patients age 65 years and older and those younger than age 65 (Table 3). Patients age 65 or older were 4 to 6 times more likely than younger patients to have a DBP <70 mm Hg (P <.001). Among older patients in cohort A, 47% were found to have a DBP of <70 mm Hg and 29% were on 3 or more antihypertensive medications at moderate or higher doses. Furthermore, most older patients in both cohorts were found to have a DBP of <70 mm Hg and/or to be on 3 or more antihypertensive medications (58% in cohort A and 60% in cohort B, compared with 20% and 37% in younger patients).