Decision Analysis in SHared decision making for Thromboprophylaxis during Pregnancy (DASH-TOP): a sequential explanatory mixed-methods pilot study.

OBJECTIVES: To gain insight into formal methods of integrating patient preferences and clinical evidence to inform treatment decisions, we explored patients' experience with a personalised decision analysis intervention, for prophylactic low-molecular-weight heparin (LMWH) in the antenatal period. DESIGN: Mixed-methods explanatory sequential pilot study. SETTING: Hospitals in Canada (n=1) and Spain (n=4 sites). Due to the COVID-19 pandemic, we conducted part of the study virtually. PARTICIPANTS: 15 individuals with a prior venous thromboembolism who were pregnant or planning pregnancy and had been referred for counselling regarding LMWH. INTERVENTION: A shared decision-making intervention that included three components: (1) direct choice exercise; (2) preference elicitation exercises and (3) personalised decision analysis. MAIN OUTCOME MEASURES: Participants completed a self-administered questionnaire to evaluate decision quality (decisional conflict, self-efficacy and satisfaction). Semistructured interviews were then conducted to explore their experience and perceptions of the decision-making process. RESULTS: Participants in the study appreciated the opportunity to use an evidence-based decision support tool that considered their personal values and preferences and reported feeling more prepared for their consultation. However, there were mixed reactions to the standard gamble and personalised treatment recommendation. Some participants could not understand how to complete the standard gamble exercises, and others highlighted the need for more informative ways of presenting results of the decision analysis. CONCLUSION: Our results highlight the challenges and opportunities for those who wish to incorporate decision analysis to support shared decision-making for clinical decisions.

Cost-effectiveness of therapies for patients with nonvalvular atrial fibrillation.

BACKGROUND: The most appropriate treatment(s) for patients with atrial fibrillation remains uncertain. OBJECTIVE: To examine the cost-effectiveness of anti-thrombotic and antiarrhythmic treatment strategies for atrial fibrillation. METHODS: We performed decision and cost-effectiveness analyses using a Markov state transition model. We gathered data from the English-language literature using MEDLINE searches and bibliographies from selected articles. We obtained financial data from nationwide physician-fee references, a medical center's cost accounting system, and one of New England's larger managed care organizations. We examined strategies that included combinations of cardioversion, antiarrhythmic therapy with quinidine, sotalol hydrochloride, or amiodarone, and anticoagulant or antiplatelet therapy. RESULTS: For a 65-year-old man with nonvalvular atrial fibrillation, any intervention results in a significant gain in quality-adjusted life years (QALYs) compared with no specific therapy. Use of aspirin results in the largest incremental gain (1.2 QALYs). Cardioversion followed by the use of amiodarone and warfarin together is the most effective strategy, yielding a gain of 2.3 QALYs compared with no specific therapy. The marginal cost-effectiveness ratios of cardioversion followed by aspirin, with or without amiodarone, are $33800 per QALY and $10800 per QALY, respectively. Cardioversion followed by amiodarone and warfarin has a marginal cost-effectiveness ratio of $92400 per QALY compared with amiodarone and aspirin. Strategies that include cardioversion followed by either quinidine or sotalol are both more expensive and less effective than competing strategies. CONCLUSIONS: Cardioversion of patients with nonvalvular atrial fibrillation followed by the use of aspirin alone or with amiodarone has a reasonable marginal cost-effectiveness ratio. While cardioversion followed by the use of amiodarone and warfarin results in the greatest gain in quality-adjusted life expectancy, it is expensive (ie, has a high marginal cost-effectiveness ratio) compared with aspirin and amiodarone. Finally, for patients who are bothered little by symptoms of atrial fibrillation, cardioversion followed by either aspirin or warfarin without subsequent antiarrhythmic therapy is the treatment of choice.

Effect of macrolides as part of initial empiric therapy on length of stay in patients hospitalized with community-acquired pneumonia.

BACKGROUND: The choice of antibiotics to treat community-acquired pneumonia (CAP) is primarily empiric, and the effect of this choice on length of stay (LOS) and mortality is largely unknown. OBJECTIVE: To examine the impact of antibiotic choice on these outcomes in general medical patients hospitalized with CAP. METHODS: One hundred patients hospitalized with CAP were prospectively identified. Seventy-six met inclusion criteria and were entered into the study. After hospital discharge, each medical chart was examined by 2 independent physicians who verified the admitting diagnosis and entered the data for antimicrobial regimens, a CAP mortality prediction tool, a social and disposition index, and other health outcomes. Patients were stratified according to the antibiotic received. Simple regression techniques were used to examine the correlation between initial therapy, specifically, ceftriaxone sodium or a macrolide, and LOS and mortality. RESULTS: Patients who received macrolides within the first 24 hours of admission had a markedly shorter LOS (2.8 days) than those not so treated (5.3 days; P = .01). This effect diminished as the interval before administering macrolides increased. Including ceftriaxone as part of the initial therapy did not appear to affect LOS. Patients given a macrolide for initial treatment did not differ significantly from those not treated in terms of mean age, mortality prediction tool score, or Social and Disposition Index score. Eleven of the 12 patients who received macrolides also received a beta-lactam antibiotic. CONCLUSION: Use of macrolides as part of an initial therapeutic regimen appears to be associated with shorter LOS.

Individualizing therapy to prevent long-term consequences of estrogen deficiency in postmenopausal women.

BACKGROUND: Alendronate sodium and raloxifene hydrochloride were recently approved for the prevention of postmenopausal osteoporosis, but data on their clinical efficacy are limited. We compared these drugs with hormone replacement therapy (HRT) to help women and physicians guide postmenopausal treatment decisions. OBJECTIVE: To help physicians understand how they can best help women choose the most beneficial therapy after menopause based on their individual risk profile. METHODS: We developed a decision analytic Markov model to compare the effects of alendronate therapy, raloxifene therapy, and HRT on risks of hip fracture, coronary heart disease (CHD), breast cancer, and life expectancy. Regression models linked individual risk factors to future disease risks and were modified by drug effects on bone density, lipid levels, and associated breast cancer effects. RESULTS: Hormone replacement therapy, alendronate therapy, and raloxifene therapy have similar predicted efficacies in preventing hip fractures (estimated relative risk, 0.57, 0.54, and 0.58, respectively). Hormone replacement therapy should be more than 10 times more effective than raloxifene therapy in preventing CHD, but raloxifene therapy may not induce breast cancer. Women at low risk for hip fracture, CHD, and breast cancer do not benefit significantly from any treatment. Among women at average risk, HRT was preferred unless raloxifene therapy could reduce the risk of breast cancer by at least 66%, compared with a 47% increase for HRT. Women at high risk for CHD benefit most from HRT; women at high risk for breast cancer but low risk for CHD benefit most from raloxifene therapy, but only if it lowers the risk of breast cancer. CONCLUSION: Because of significant differences in the impact of these drugs, treatment choice depends on an individual woman's risk for hip fracture, CHD, and breast cancer.

Prophylactic use of the intra-aortic balloon pump in high-risk cardiac patients undergoing noncardiac surgery: a decision analytic view.

OBJECTIVE: As the indications for the intra-aortic balloon pump (IABP) continue to evolve, a potential new use may be the prophylactic preoperative insertion of the IABP in the high-risk cardiac patient undergoing noncardiac surgery. Our objective is to present a general approach to the high-risk cardiac patient who may benefit from the prophylactic insertion of the IABP. DESIGN: Case reports and a decision analysis. METHODS: A decision model was constructed that weighs the risk of life-threatening postoperative complications against the risk of vascular complications, including surgery and possible amputation, from IABP insertion. RESULTS AND CONCLUSIONS: A review of the literature identified 10 patients who underwent IABP placement prior to noncardiac surgery. These patients, along with our three cases, define a population of patients for whom the prophylactic IABP may be useful. This population includes patients with coronary artery disease (CAD) for whom bypass grafting is not an option due to: (1) inoperable CAD; (2) a severe coexisting disease process (such as a malignancy); or (3) the emergent nature of the noncardiac procedure. The decision analysis suggests that patients whose preoperative assessment places them at very high risk for postoperative complications (Goldman class IV or Detsky class III undergoing major surgery) may benefit the most from prophylactic placement of an IABP prior to noncardiac surgery.

Warfarin for dilated cardiomyopathy: a bloody tough pill to swallow?

Although current recommendations for the treatment of dilated cardiomyopathy include long-term anticoagulation to diminish the likelihood of systemic embolization, there have been no clinical trials examining the effectiveness of anticoagulation in preventing systemic embolization in these patients. Furthermore, those recommendations do not address the issue of the quality of life associated with long-term warfarin therapy. Using decision analysis, the authors examined the benefits and risks of long-term anticoagulation for patients 35 to 75 years of age who have dilated cardiomyopathy. The results show that anticoagulant therapy increases quality-adjusted life expectancy by 76 to 128 days, depending on the patient's age. Sensitivity analysis, however, demonstrates that the outcome is dependent on the disutility associated with long-term warfarin therapy. Interestingly, anticoagulation exerts most of its benefit by preventing pulmonary embolization, not systemic embolization. The authors conclude that the current recommendation to anticoagulate these patients, although probably correct for many patients, should take into consideration the change in lifestyle imposed by long-term anticoagulant therapy. For some patients, the benefit may not outweigh the sacrifice.

Aortic aneurysm in a 74-year-old man with coronary disease and obstructive lung disease: is double jeopardy enough?

A previous decision analysis examined a patient with severe CAD, diminished ventricular function, and an abdominal aortic aneurysm and also concluded that CABG followed by aneurysm repair was optimal. This patient, who had well-preserved cardiac function but severely compromised pulmonary status, stood to gain less from CABG than would a patient with more severe coronary disease, thus accounting for the "close-call" between the CABG-AAA and AAA only strategies. Nevertheless, the analysis did emphasize the benefit of aneurysm repair, whether done alone or after CABG. The analysis also highlighted the significant risk of aneurysm rupture the patient is exposed to while recovering from CABG surgery. The operative mortality risks of the two procedures are similar; thus, the patient's total operative risk is approximately doubled if he undergoes both procedures rather than aneurysm repair alone. The key question raised by the analysis is whether this double jeopardy is more than compensated by the degree to which prior CABG reduces both short-term cardiac risk at subsequent aneurysm repair and long-term cardiac mortality. For this patient, who had good cardiac function, the gains appeared sufficient to offset the interval risk of aneurysm rupture and the additional risk associated with a surgical procedures. THE REAL WORLD The patient indeed underwent and tolerated CABG, although he had a stormy prolonged postoperative course due to pulmonary failure. After discharge from the hospital, he declined readmission for repair of the aneurysm. We did not model that possibility, clearly an inadequacy in our tree. Some six months later, the patient was still alive and was, reluctantly, readmitted for aneurysmorrhaphy. At that time, however, his pulmonary function had deteriorated and both the anesthesiologist and the pulmonary consultant stated unequivocally that further surgery was now impossible. In retrospect, the expected utility of CABG without aneurysm repair (thus providing only a decrease in the long-term mortality risk from his CAD) would have been 1.95 (DEALE) or 2.06 (Markov) years. Sensitivity analysis revealed that, even if long-term cardiac risk were completely eliminated by CABG, immediate aneurysm repair would have been a better approach had the patient's physicians known he would be likely to refuse or not be a candidate for the second operation. In summary, although the patient's comorbidities did indeed place him at significant operative risk for either aneurysmorrhaphy alone or two sequential procedures, the benefits to be gained were shown to far outweigh the risks when compared with expectant observation.(ABSTRACT TRUNCATED AT 400 WORDS)

Inaccuracies in estimates of life expectancies of patients with bronchial cancer in clinical decision making.

Approximations of life expectancy in clinical decision making frequently assume constant disease-specific ("excess") mortality hazards over age at diagnosis and over time from diagnosis. This assumption is inconsistent with the longer relative survival of younger patients with bladder cancer and with the declines in mortality hazards from bladder and breast cancers over time from diagnosis. To estimate the error that may result from these assumptions, the authors derived excess mortality hazards from the Surveillance, Epidemiology and End Result (SEER) tumor registry for bronchial cancers stratified by age at diagnosis and time from diagnosis. They compared the life expectancies calculated by a model using an average constant annual cancer-specific mortality hazard over time from diagnosis with those calculated using data-derived cancer-specific annual mortality hazards that varied as a function of time from diagnosis. For younger patients with less advanced disease, the constant-average-mortality model underestimated life expectancies by up to 50% relative to those predicted by the time-variant model. For those over 75 years old at diagnosis, and for all patients with advanced disease, the constant-average-mortality model overestimated life expectancies by up to 65% relative to those predicted by the time-variant model. The authors conclude that predictions of life expectancy with bronchial cancer, and probably with other neoplasms, are limited by the widespread use of oversimplified methods of calculation and by the lack of data describing mortality hazards as a function of time from diagnosis.(ABSTRACT TRUNCATED AT 250 WORDS)

Automated critiquing of medical decision trees.

The authors developed a decision tree-critiquing program (called BUNYAN) that identifies potential modeling errors in medical decision trees. The program's critiques are based on the structure of a decision problem, obtained from an abstract description specifying only the basic semantic categories of the model's components. A taxonomy of node and branch types supplies the primitive building blocks for representing decision trees. Bunyan detects potential problems in a model by matching general pattern expressions that refer to these primitives. A small set of general principles justifies critiquing rules that detect four categories of potential structural problems: impossible strategies, dominated strategies, unaccountable violations of symmetry, and omission of apparently reasonable strategies. Although critiquing based on structure alone has clear limitations, principled structural analysis constitutes the core of a methodology for reasoning about decision models.