Background: In diabetic adults, tight control of risk factors reduces complications.
Objective: To determine whether failure to make visits, monitor risk factors, or intensify therapy affects control of blood pressure, glucose, and lipids.
Design: A non-concurrent, prospective study of data from electronic files and standardized abstraction of hard-copy medical records for the period 1/1/1999-12/31/2001.
Participants: Three hundred eighty-three adults with diabetes managed in an academically affiliated managed care program.
Measurements: Main exposure variable: Intensification of therapy or failure to intensify, reckoned on a quarterly basis.
Main outcome measure: Hemoglobin A1c (A1c), systolic blood pressure (SBP), and LDL-cholesterol at the end of the interval.
Results: In this visit-adherent cohort, control of glycemia and lipids showed improvement over 24 months, but many patients did not achieve targets. Only those with the worst blood pressure control (SBP >or=160 mmHg) showed any improvement over 2 years. Failure to intensify treatment in patients who kept visits was the single strongest predictor of sub-optimal control. Compared to their counterparts with no failures of intensification, patients with failures in >or=3 quarters showed markedly worse control of blood glucose (A1c 1.4% higher: 95% CI: 0.7, 2.1); hypertension (SBP 22.2 mmHg higher: 95% CI: 16.6, 27.9) and LDL cholesterol (LDL 43.7 mg/dl higher: 95% CI: 24.1, 63.3). These relationships were strong, graded, and independent of socio-demographic factors, baseline risk factor values, and co-morbidities.
Conclusions: Failure to intensify therapy leads to suboptimal control, even with adequate visits and monitoring. Interventions designed to promote appropriate intensification should enhance diabetes care in primary practice.