Recruitment strategies and challenges in a large intervention trial: Systolic Blood Pressure Intervention Trial.

BACKGROUND: The Systolic Blood Pressure Intervention Trial is a multicenter, randomized clinical trial of 9361 participants with hypertension who are ≥50 years old. The trial is designed to evaluate the effect of intensive systolic blood pressure control (systolic blood pressure goal <120 mm Hg) compared to standard control (systolic blood pressure goal <140 mm Hg) on cardiovascular events using commonly prescribed antihypertensive medications and lifestyle modification. OBJECTIVE: To describe the recruitment strategies and lessons learned during recruitment of the Systolic Blood Pressure Intervention Trial cohort and five targeted participant subgroups: pre-existing cardiovascular disease, pre-existing chronic kidney disease, age ≥75 years, women, and minorities. METHODS: In collaboration with the National Institutes of Health Project Office and Systolic Blood Pressure Intervention Trial Coordinating Center, five Clinical Center Networks oversaw clinical site selection, recruitment, and trial activities. Recruitment began on 8 November 2010 and ended on 15 March 2013 (about 28 months). Various recruitment strategies were used, including mass mailing, brochures, referrals from healthcare providers or friends, posters, newspaper ads, radio ads, and electronic medical record searches. RESULTS: Recruitment was scheduled to last 24 months to enroll a target of 9250 participants; in just over 28 months, the trial enrolled 9361 participants. The trial screened 14,692 volunteers, with 33% of initial screens originating from the use of mass mailing lists. Screening results show that participants also responded to recruitment efforts through referral by Systolic Blood Pressure Intervention Trial staff, healthcare providers, or friends (45%); brochures or posters placed in clinic waiting areas (15%); and television, radio, newspaper, Internet ads, or toll-free numbers (8%). The overall recruitment yield (number randomized/number screened) was 64% (9361 randomized/14,692 screened), 77% for those with cardiovascular disease, 79% for those with chronic kidney disease, 70% for those aged ≥75 years, 55% for women, and 61% for minorities. As recruitment was observed to lag behind expectations, additional clinics were included and inclusion criteria were broadened, keeping event rates and trial power in mind. As overall recruitment improved, a greater focus on subgroup recruitment was implemented. CONCLUSION: Systolic Blood Pressure Intervention Trial met its overall projected recruitment goal using diverse, locally adapted enrollment strategies to specifically target persons with cardiovascular disease, chronic kidney disease, ≥75 years old, women, and minority subgroups. The trial exceeded its recruitment goal for minorities but found it a challenge to meet the competing demands of the targeted goals for recruiting into the remaining four subgroups. Important lessons include the imperative to monitor the recruitment process carefully, decide early to add new clinics or modify inclusion and exclusion criteria if recruitment lags, and consider limiting enrollment to subgroups only. We found benefit in using multiple recruitment sources simultaneously; mass mailing produced the largest number of participants, but referrals resulted in the greater randomization yield.

Differential impact of cardiovascular disease (CVD) risk factor clustering on CVD and renal disease among African-American and white patients with type 2 diabetes mellitus.

OBJECTIVES: To determine if clustering of cardiovascular disease (CVD) risk factors has a differential impact on CVD and renal disease among African Americans compared to Whites with type 2 diabetes DESIGN: Cross-sectional. METHODS: Prevalent CVD, macroalbuminuria, and CVD risk factors were measured in 323 African-American and White adult patients with type 2 diabetes. CVD risk factors were dichotomized according to standard guidelines. Data were analyzed by race according to the presence of any 3 or more CVD risk factors. RESULTS: Despite a similar prevalence of hypertension, the prevalence of macroalbuminuria in the presence of 3 or more CVD risk factors tended to be higher among African Americans compared to Whites (28.9% vs 13.6%, P = 0.05). The presence of 3+ CVD risk factors was associated with an odds ratio (OR) of 2.5 (P = 0.001, 95% CI, 1.44-4.27) for macroalbuminuria in African Americans compared to an OR of 1.4 (P = 0.25, 95% CI, 0.78-2.53) in Whites. The race/3+ CVD risk factors interaction was statistically significant (P = 0.007). Conversely, the presence of 3+ risk factors was associated with an OR of 1.6 (P = 0.019, 95% CI, 1.08-2.28) for CVD in Whites compared to an OR of 0.8 (P = .287, 95% CI, 0.54-1.20) in African Americans. The prevalence of any CVD in the presence of 3+ risk factors was 61% and 49% in Whites and African Americans respectively (P = .217). The race/3+ CVD risk factors interaction was statistically significant (P = 0.029). CONCLUSIONS: These findings suggest that among persons with diabetes, a clustering of 3+ CVD risk factors is more predictive for renal disease among African Americans, and more predictive for CVD in Whites. Further research should clarify the impact of CVD risk factor clustering on the incidence of vascular disease among African Americans and Whites with type 2 diabetes.

Hospitalizations and outcomes for diabetic gastroparesis in North Carolina.

BACKGROUND: Population-based data to assess the extent of gastroparesis in the diabetic population are scarce. We examined the demographic and clinical characteristics associated with hospital admissions for diabetic gastroparesis in North Carolina. METHODS: Data from the 1998 North Carolina Hospital Discharge database were abstracted from records in which gastroparesis and diabetes mellitus were listed as simultaneous diagnoses. RESULTS: There were 1476 discharges meeting our criteria, with total charges of $11,378,446 over 7850 total hospital days. Most patients were female (65.8%), > or = 45 years of age (54.5%), and had Medicare as the primary payer (52.1%). While most of these patients were admitted under emergency or urgent circumstances, the vast majority had routine discharges. CONCLUSION: Despite some limitations, these data indicate that diabetic gastroparesis is not uncommon, but can be treated effectively.