William B. Stason

Foundations of Cost-Effectiveness Analysis for Health and Medical Practices

Limits on health-care resources mandate that resource-allocation decisions be guided by considerations of cost in relation to expected benefits. In cost-effectiveness analysis, the ratio of net health-care costs to net health benefits provides an index by which priorities may be set. Quality-of-life concerns, including both adverse and beneficial effects of therapy, may be incorporated in the calculation of health benefits as adjustments to life expectancy. The timing of future benefits and costs may be accounted for by the appropriate use of discounting. Current decisions must inevitably be based on imperfect information, but sensitivity analysis can increase the level of confidence in some decisions while suggesting areas where further research may be valuable in guiding others. Analyses should be adaptable to the needs of various health-care decision makers, including planners, administrators and providers.

Use of Cardiac Rehabilitation by Medicare Beneficiaries After Myocardial Infarction or Coronary Bypass Surgery

Background— Cardiac rehabilitation (CR) is effective in prolonging survival and reducing disability in patients with coronary heart disease. However, national use patterns and predictors of CR use have not been evaluated thoroughly. Methods and Results— Using Medicare claims, we analyzed outpatient (phase II) CR use after hospitalizations for acute myocardial infarctions or coronary artery bypass graft surgery in 267 427 fee-for-service beneficiaries aged ≥65 years who survived for at least 30 days after hospital discharge. We used multivariable analyses to identify predictors of CR use and to quantify geographic variations in its use. We obtained unadjusted, adjusted-smoothed, and standardized rates of CR use by state. Overall, CR was used in 13.9% of patients hospitalized for acute myocardial infarction and 31.0% of patients who underwent coronary artery bypass graft surgery. Older individuals, women, nonwhites, and patients with comorbidities (including congestive heart failure, previous stroke, diabetes mellitus, or cancer) were significantly less likely to receive CR. Coronary artery bypass graft surgery during the index hospitalization, higher median household income, higher level of education, and shorter distance to the nearest CR facility were important predictors of higher CR use. Adjusted CR use varied 9-fold among states, ranging from 6.6% in Idaho to 53.5% in Nebraska. The highest CR use rates were clustered in the north central states of the United States. Conclusions— CR use is relatively low among Medicare beneficiaries despite convincing evidence of its benefits and recommendations for its use by professional organizations. Use is higher after coronary artery bypass graft surgery than with acute myocardial infarctions not treated with revascularization procedures and varies dramatically by state and region of the United States.

Relative and Absolute Excess Risks of Coronary Heart Disease among Women Who Smoke Cigarettes

We prospectively examined the incidence of coronary heart disease in relation to cigarette smoking in a cohort of 119,404 female nurses who were 30 to 55 years of age in 1976 and were free of diagnosed coronary disease. During six years of follow-up, 65 of the women died of fatal coronary heart disease and 242 had a nonfatal myocardial infarction. The number of cigarettes smoked per day was positively associated with the risk of fatal coronary heart disease (relative risk = 5.5 for greater than or equal to 25 cigarettes per day), nonfatal myocardial infarction (relative risk = 5.8), and angina pectoris (relative risk = 2.6). Even smoking 1 to 4 or 5 to 14 cigarettes per day was associated with a twofold to three-fold increase in the risk of fatal coronary heart disease or nonfatal infarction. Overall, cigarette smoking accounted for approximately half these events. The attributable (absolute excess) risk of coronary heart disease due to current smoking was highest among women who were already at increased risk because of older age, a parental history of myocardial infarction, a higher relative weight, hypertension, hypercholesterolemia, or diabetes. In contrast, former smokers had little, if any, increase in risk. These prospective data emphasize the importance of cigarette smoking as a determinant of coronary heart disease in women, as well as the markedly increased hazards associated with this habit in combination with other risk factors for this disease.

Sham device v inert pill: randomised controlled trial of two placebo treatments

Abstract Objective To investigate whether a sham device (a validated sham acupuncture needle) has a greater placebo effect than an inert pill in patients with persistent arm pain. Design A single blind randomised controlled trial created from the two week placebo run-in periods for two nested trials that compared acupuncture and amitriptyline with their respective placebo controls. Comparison of participants who remained on placebo continued beyond the run-in period to the end of the study. Setting Academic medical centre. Participants 270 adults with arm pain due to repetitive use that had lasted at least three months despite treatment and who scored ≥3 on a 10 point pain scale. Interventions Acupuncture with sham device twice a week for six weeks or placebo pill once a day for eight weeks. Main outcomemeasures Arm pain measured on a 10 point pain scale. Secondary outcomes were symptoms measured by the Levine symptom severity scale, function measured by Pranskys upper extremity function scale, and grip strength. Results Pain decreased during the two week placebo run-in period in both the sham device and placebo pill groups, but changes were not different between the groups (−0.14, 95% confidence interval −0.52 to 0.25, P = 0.49). Changes in severity scores for arm symptoms and grip strength were similar between groups, but arm function improved more in the placebo pill group (2.0, 0.06 to 3.92, P = 0.04). Longitudinal regression analyses that followed participants throughout the treatment period showed significantly greater downward slopes per week on the 10 point arm pain scale in the sham device group than in the placebo pill group (−0.33 (−0.40 to −0.26) v −0.15 (−0.21 to −0.09), P = 0.0001) and on the symptom severity scale (−0.07 (−0.09 to −0.05) v −0.05 (−0.06 to −0.03), P = 0.02). Differences were not significant, however, on the function scale or for grip strength. Reported adverse effects were different in the two groups. Conclusions The sham device had greater effects than the placebo pill on self reported pain and severity of symptoms over the entire course of treatment but not during the two week placebo run in. Placebo effects seem to be malleable and depend on the behaviours embedded in medical rituals.

Hyperuricemia in primary and renal hypertension.

AN increased incidence of hyperuricemia in patients with primary hypertension has been cited in several reports.1 2 3 The present investigation of the population of the Hypertension-Nephritis Clinic of the Presbyterian Hospital in New York City confirms this observation among patients with either primary or renal hypertension, treated and untreated. The data from a related series of studies suggest that the hyperuricemia in both types of hypertension results from diminished renal excretion of urate. Altered lactic acid metabolism in hypertensive disease may account in part for the altered renal transport of uric acid.4 The results also raise the possibility that elevations of .xa0.xa0.

Forecasting coronary heart disease incidence, mortality, and cost: the Coronary Heart Disease Policy Model.

A computer simulation model was developed to project the future mortality, morbidity, and cost of coronary heart disease (CHD) in the United States population. The model contains a demographic-epidemiologic (DE) submodel, which stimulates the distribution of coronary risk factors and the conditional incidence of CHD in a demographically evolving population; a bridge submodel, which determines the outcome of the initial CHD event; and a disease history (DH) submodel, which simulates subsequent events in persons with a previous CHD event. The user of the model may simulate the effects of interventions, either preventive (i.e., risk factor modification) or therapeutic, upon mortality, morbidity, and cost for up to a 30-year period. If there were no future changes in risk factors or the efficacy of therapies after 1980, baseline projections indicate that the aging of the population, and especially the maturation of the post-World War II baby-boom generation, would increase CHD prevalence and annual incidence, mortality, and costs by about 40-50 per cent by the year 2010. Unprecedented reductions in risk factors would be required to offset these demographic effects on the absolute incidence of CHD. The specific forecasts could be inaccurate, however, as a consequence of erroneous assumptions or misestimated baseline data, and the model awaits validation based on actual future data.

Cardiac Rehabilitation and Survival in Older Coronary Patients

OBJECTIVESnThis study assessed the effects of cardiac rehabilitation (CR) on survival in a large cohort of older coronary patients.nnnBACKGROUNDnRandomized controlled trials and meta-analyses have shown that CR improves survival. However, trial participants have been predominantly middle-aged, low- or moderate-risk, white men.nnnMETHODSnThe population consisted of 601,099 U.S. Medicare beneficiaries who were hospitalized for coronary conditions or cardiac revascularization procedures. One- to 5-year mortality rates were examined in CR users and nonusers using Medicare claims and 3 analytic techniques: propensity-based matching, regression modeling, and instrumental variables. The first method used 70,040 matched pairs, and the other 2 techniques used the entire cohort.nnnRESULTSnOnly 12.2% of the cohort used CR, and those users averaged 24 sessions. Each technique showed significantly lower (p < 0.001) 1- to 5-year mortality rates in CR users than nonusers. Five-year mortality relative reductions were 34% in propensity-based matching, 26% from regression modeling, and 21% with instrumental variables. Mortality reductions extended to all demographic and clinical subgroups including patients with acute myocardial infarctions, those receiving revascularization procedures, and those with congestive heart failure. The CR users with 25 or more sessions were 19% relatively less likely to die over 5 years than matched CR users with 24 or fewer sessions (p < 0.001).nnnCONCLUSIONSnMortality rates were 21% to 34% lower in CR users than nonusers in this socioeconomically and clinically diverse, older population after extensive analyses to control for potential confounding. These results are of similar magnitude to those observed in published randomized controlled trials and meta-analyses in younger, more selected populations.

Allocation of Resources to Manage Hypertension

Hypertension is one of the foremost public-health problems facing this nation. Its high prevalence, the enhanced risks of mortality and morbidity from the cardiovascular and cerebrovascular disease...

The placebo effect in irritable bowel syndrome trials: a meta-analysis1

Abstractu2002 Background:u2002 Despite the apparent high placebo response rate in randomized placebo‐controlled trials (RCT) of patients with irritable bowel syndrome (IBS), little is known about the variability and predictors of this response.

Functional electrostimulation in poststroke rehabilitation: a meta-analysis of the randomized controlled trials.

OBJECTIVEnTo assess the efficacy of functional electrical stimulation (FES) in the rehabilitation of hemiparesis in stroke.nnnDESIGNnA meta-analysis combined the reported randomized controlled trials of FES in stroke, using the effect size method of Glass, and the DerSimonian-Laird Random Effects Method for pooling studies.nnnSETTINGnThe included studies were published between 1978 and 1992. They were conducted in academic rehabilitation medicine settings.nnnPATIENTSnIn all included studies, patients were in poststroke rehabilitation. The mean time after stroke varied from 1.5 to 29.2 months.nnnINTERVENTIONnFES applied to a muscle or associated nerve in a hemiparetic extremity was compared to No FES.nnnMAIN OUTCOME MEASUREnChange in paretic muscle force of contraction following FES was compared to change without FES.nnnRESULTSnFor the four included studies, the mean effect size was .63 (95% CI: .29, .98). This result was statistically significant (p < .05).nnnCONCLUSIONnPooling from randomized trials supports FES as promoting recovery of muscle strength after stroke. This effect is statistically significant. There is a reasonable likelihood of clinical significance as well.