Medicare Star excludes diabetes patients with poor CVD risk factor control

Area of Science:

• Health Services Research
• Quality Improvement
• Cardiovascular Disease Management

Background:

• Medicare Star quality measures now include medication adherence for diabetes, hypertension, and hyperlipidemia.
• These measures exclude patients with fewer than two medication fills (early nonadherence) and those using insulin.
• This exclusion criteria may impact the accurate assessment of cardiovascular disease (CVD) risk factor control in patients with diabetes.

Purpose of the Study:

• To determine the proportion of diabetic patients prescribed cardiovascular medications who are excluded from Medicare Star adherence measures.
• To evaluate the association between adherence (as defined by Star metrics) and exclusion from these metrics with CVD risk factor control.

Main Methods:

• A cross-sectional, population-based analysis was conducted on 129,040 patients with diabetes aged 65 years or older.
• Data were sourced from three Kaiser Permanente regions in 2010.
• Adjusted risk ratios were calculated to assess the relationship between Star adherence, exclusion from Star metrics, and control of glycated hemoglobin (A1C), low-density lipoprotein cholesterol (LDL-C), and systolic blood pressure (SBP).

Main Results:

• Twenty-seven percent of diabetic patients on oral medications were excluded from Star metrics.
• Star-defined nonadherence was linked to poorer control of A1C, LDL-C, and SBP.
• Exclusion due to early nonadherence or insulin use was strongly associated with poor control of A1C, LDL-C, and SBP.

Conclusions:

• Medicare Star adherence measures may underestimate medication nonadherence prevalence in diabetes.
• These measures exclude a significant number of elderly patients with diabetes who are at high risk for poor CVD outcomes.
• Future quality measures should encompass all patients treated for CVD risk to ensure comprehensive care and accurate assessment.