George R. Bergus

Comparative Antihypertensive Effects of Hydrochlorothiazide and Chlorthalidone on Ambulatory and Office Blood Pressure

Low-dose thiazide-type diuretics are recommended as initial therapy for most hypertensive patients. Chlorthalidone has significantly reduced stroke and cardiovascular end points in several landmark trials; however, hydrochlorothiazide remains favored in practice. Most clinicians assume that the drugs are interchangeable, but their antihypertensive effects at lower doses have not been directly compared. We conducted a randomized, single-blinded, 8-week active treatment, crossover study comparing chlorthalidone 12.5 mg/day (force-titrated to 25 mg/day) and hydrochlorothiazide 25 mg/day (force-titrated to 50 mg/day) in untreated hypertensive patients. The main outcome, 24-hour ambulatory blood pressure (BP) monitoring, was assessed at baseline and week 8, along with standard office BP readings every 2 weeks. Thirty patients completed the first active treatment period, whereas 24 patients completed both. An order–drug–time interaction was observed with chlorthalidone; therefore, data from only the first active treatment period was considered. Week 8 ambulatory BPs indicated a greater reduction from baseline in systolic BP with chlorthalidone 25 mg/day compared with hydrochlorothiazide 50 mg/day (24-hour mean = −12.4±1.8 mm Hg versus −7.4±1.7 mm Hg; P=0.054; nighttime mean = −13.5±1.9 mm Hg versus −6.4±1.8 mm Hg; P=0.009). Office systolic BP reduction was lower at week 2 for chlorthalidone 12.5 mg/day versus hydrochlorothiazide 25 mg/day (−15.7±2.2 mm Hg versus −4.5±2.1 mm Hg; P=0.001); however, by week 8, reductions were statistically similar (−17.1±3.7 versus −10.8±3.5; P=0.84). Within recommended doses, chlorthalidone is more effective in lowering systolic BPs than hydrochlorothiazide, as evidenced by 24-hour ambulatory BPs. These differences were not apparent with office BP measurements.

Physician and pharmacist collaboration to improve blood pressure control.

BACKGROUNDnStudies have demonstrated that blood pressure (BP) control can be improved when clinical pharmacists assist with patient management. The objective of this study was to evaluate if a physician and pharmacist collaborative model in community-based medical offices could improve BP control.nnnMETHODSnThis was a prospective, cluster randomized, controlled clinical trial with clinics randomized to a control group (n = 3) or to an intervention group (n = 3). The study enrolled 402 patients (mean age, 58.3 years) with uncontrolled hypertension. Clinical pharmacists made drug therapy recommendations to physicians based on national guidelines. Research nurses performed BP measurements and 24-hour BP monitoring.nnnRESULTSnThe mean (SD) guideline adherence scores increased from 49.4 (19.3) at baseline to 53.4 (18.1) at 6 months (8.1% increase) in the control group and from 40.4 (22.6) at baseline to 62.8 (13.5) at 6 months (55.4% increase) in the intervention group (P = .09 for adjusted between-group comparison). The mean BP decreased 6.8/4.5 mm Hg in the control group and 20.7/9.7 mm Hg in the intervention group (P < .05 for between-group systolic BP comparison). The adjusted difference in systolic BP was -12.0 (95% confidence interval [CI], -24.0 to 0.0) mm Hg, while the adjusted difference in diastolic BP was -1.8 (95% CI, -11.9 to 8.3) mm Hg. The 24-hour BP levels showed similar effect sizes. Blood pressure was controlled in 29.9% of patients in the control group and in 63.9% of patients in the intervention group (adjusted odds ratio, 3.2; 95% CI, 2.0-5.1; P < .001).nnnCONCLUSIONSnA physician and pharmacist collaborative intervention achieved significantly better mean BP and overall BP control rates compared with a control group. Additional research should be conducted to evaluate efficient strategies to implement team-based chronic disease management.nnnTRIAL REGISTRATIONnclinicaltrials.gov Identifier: NCT00201019.

A Cluster Randomized Trial to Evaluate Physician/Pharmacist Collaboration to Improve Blood Pressure Control

This was a prospective, cluster randomized controlled trial in patients with uncontrolled hypertension aged 21 to 85 years (mean, 61 years). Pharmacists made recommendations to physicians for patients in the intervention clinics (n=101) but not patients in the control clinics (n=78). The mean adjusted difference in systolic blood pressure (BP) between the control and intervention groups was 8.7 mm Hg (95% confidence interval [CI], 4.4–12.9), while the difference in diastolic BP was 5.4 mm Hg (CI, 2.8–8.0) at 9 months. The 24‐hour BP levels showed similar effects, with a mean systolic BP level that was 8.8 mm Hg lower (CI, 5.0–12.6) and a mean diastolic BP level that was 4.6 mm Hg (CI, 2.4–6.8) lower in the intervention group. BP was controlled in 89.1% of patients in the intervention group and 52.9% in the control group (adjusted odds ratio, 8.9; CI, 3.8–20.7; P<.001). Physician/pharmacist collaboration achieved significantly better mean BP values and overall BP control rates, primarily by intensification of medication therapy and improving patient adherence.

Effect of a patient's psychiatric history on physicians' estimation of probability of disease

A questionnaire was mailed to 300 Iowa family physicians to determine the influence of a prior psychiatric history on decision making. The response rate was 77%. Respondents were less likely to believe that a patient had serious illness when presenting with a severe headache or abdominal pain if the patient had a prior history of depression (P<.05) or prior history of somatic complaints (P<.05), compared with a patient with no past history. Respondents were less likely to report that they would order testing for a patient with headache or abdominal pain if the patient had a history of depression (P<.05, P=.08, respectively) or somatic complaints (P<.01). Differences in likelihood of ordering tests were not significant after adjusting for differences in estimated probability of disease. We conclude that physicians respond differently to patients with psychiatric illness because of their estimation of pretest probability of disease rather than bias. We conclude that past psychiatric history influences physicians’ estimation of disease presence and willingness to order tests.

The influence of irrelevant anchors on the judgments and choices of doctors and patients

Background. Little research has examined how anchor numbers affect choice, despite several decades of research showing that judgments typically and robustly assimilate toward irrelevant anchors. Methods. In one experiment, HIV-positive patients (N = 99) judged the chances that sexual partners would become infected with HIV after sex using a defective condom and then indicated their choices of remedial action. In a second experiment, Iowa physicians (N =191) rated the chances that hypothetical patients had a pulmonary embolism and then formulated a treatment plan. Results. Irrelevant anchor numbers dramatically affected judgments by HIV-infected patients of the chances of HIV infection after a condom broke during sex (43% v. 64% in the low- and high-anchor conditions, respectively) and judgments by doctors of the chances of pulmonary embolism (23% v. 53%, respectively). Despite large anchoring effects in judgement, treatment choices did not differ between low-and high-anchor conditions. Accountability did not reduce the anchoring bias in the doctors judgments. Discussion. The practical implications of anchoring for risk judgments are potentially large, but the bias may be less relevant to treatment choices. The findings suggest that the theoretical underpinnings of the anchoring bias may be more complex than previously thought. Key words: anchoring bias; assimilation effect; contrast effect; risk perception. (Med Decis Making 2007; 27: 203—211)

Explicit and Implicit Evaluation of Physician Adherence to Hypertension Guidelines

This study evaluated physician adherence to the Seventh Report of the Joint National Committee on Prevention, Detection, Evaluation, and Treatment of High Blood Pressure (JNC 7) hypertension guidelines in 6 community‐based clinics. Explicit review of retrospective medical record data for patients with uncontrolled hypertension measured guideline adherence using 22 criteria. Mean overall guideline adherence was 53.5% and did not improve significantly over time. Random‐effects models demonstrated significant associations between guideline adherence and various demographic and medical predictors, including age, minority status, comorbid conditions, and number of medications. A subsequent implicit review evaluated the degree to which nonadherence was justifiable and identified factors that might have affected adherence. Nonadherence was rated as justifiable for only 6.6% of the failed explicit criteria. In general, adherence to the JNC 7 guidelines was modest even when barriers that might have affected adherence were taken into consideration.

Presenting risks and benefits to patients

OBJECTIVE: To investigate whether patients are influenced by the order in which they learn the risks and benefits of a treatment and whether this effect is attenuated by a treatment’s associated risk and/or benefit.DESIGN: Subjects were randomized to review 1 of 6 medical treatment information brochures.SETTING: Waiting rooms of primary care physicians at an academic health center.PARTICIPANTS: Six hundred eighty-five subjects, ages 18 to 70 years.INTERVENTION: Subjects reviewed 1 of 3 treatments for symptomatic carotid artery disease. The first (aspirin) was low-risk/low-benefit, the second (carotid endarterectomy surgery) was high-risk/high-benefit, and the third (extracranial-to-intracranial bypass surgery) was high-risk but of unknown benefit. Patients were also randomized to receive information about risk either before or after benefit. Patients were asked to rate the favorability of the treatment on a scale of 0 to 100 and whether they would consent. Finally, subjects rated how their decisions were influenced by the risk and benefit information.MAIN RESULTS: Subjects evaluating aspirin therapy were influenced by the order of the risk/benefit information. Those learning about risks after benefits had a greater drop in their favorability ratings than subjects learning about risks before benefits (−10.9 vs −5.2 on a 100-point scale; P=.02) and were less likely to consent (odds ratio, 2.27; P=.04). In contrast, subjects evaluating carotid endarterectomy and extracranial-to-intracranial bypass were not influenced by information order. When subjects were influenced by the order of information, they also reported that the treatment’s risk had less influence on their decision making (P<.01).CONCLUSIONS: When patients evaluate low-risk medical interventions, they may form less favorable impressions of the treatment and be less likely to consent to the treatment when they learn about the risks after the benefits. Order effects were not observed with high-risk treatments regardless of potential benefits.

Order of Information Affects Clinical Judgment

Family practice physicians read a case vignette describing a patient with a history of lung cancer, a new transient neurological disturbance, and a normal computerized tomographic (CT) scan of the head. They then estimated the probabilities of two diagnoses: transient ischemic attack (TIA) and brain tumor. Probability estimates of TIA were lower if the history of lung cancer was presented at the end of the case rather than at the beginning. This recency effect was found for both more and less experienced physicians and whether subjects were prompted for a single end-of-sequence probability judgment or multiple step-by-step judgments after each piece of information. These results are inconsistent with Hogarth and Einhorns (1992) belief-adjustment model, which predicts a recency effect for the step-by-step condition but a primacy effect for the end-of-sequence condition.

The validity of performance-based measures of clinical reasoning and alternative approaches.

Contextu2002 The development of a valid and reliable measure of clinical reasoning ability is a prerequisite to advancing our understanding of clinically relevant cognitive processes and to improving clinical education. A record of problem‐solving performances within standardised and computerised patient simulations is often implicitly assumed to reflect clinical reasoning skills. However, the validity of this measurement method for assessing clinical reasoning is open to question.

Fertility Awareness-Based Methods : Another Option for Family Planning

Modern fertility awareness-based methods (FABMs) of family planning have been offered as alternative methods of family planning. Billings Ovulation Method, the Creighton Model, and the Symptothermal Method are the more widely used FABMs and can be more narrowly defined as natural family planning. The first 2 methods are based on the examination of cervical secretions to assess fertility. The Symptothermal Method combines characteristics of cervical secretions, basal body temperature, and historical cycle data to determine fertility. FABMs also include the more recently developed Standard Days Method and TwoDays Method. All are distinct from the more traditional rhythm and basal body temperature methods alone. Although these older methods are not highly effective, modern FABMs have typical-use unintended pregnancy rates of 1% to 3% in both industrialized and nonindustrialized nations. Studies suggest that in the United States physician knowledge of FABMs is frequently incomplete. We review the available evidence about the effectiveness for preventing unintended pregnancy, prognostic social demographics of users of the methods, and social outcomes related to FABMs, all of which suggest that family physicians can offer modern FABMs as effective means of family planning. We also provide suggestions about useful educational and instructional resources for family physicians and their patients.