Mary E. Charlson

Validation of a combined comorbidity index.

The basic objective of this paper is to evaluate an age-comorbidity index in a cohort of patients who were originally enrolled in a prospective study to identify risk factors for peri-operative complications. Two-hundred and twenty-six patients were enrolled in the study. The participants were patients with hypertension or diabetes who underwent elective surgery between 1982 and 1985 and who survived to discharge. Two-hundred and eighteen patients survived until discharge. These patients were followed for at least five years post-operatively. The estimated relative risk of death for each comorbidity rank was 1.4 and for each decade of age was 1.4. When age and comorbidity were modelled as a combined age-comorbidity score, the estimated relative risk for each combined age-comorbidity unit was 1.45. Thus, the estimated relative risk of death from an increase of one in the comorbidity score proved approximately equal to that from an additional decade of age. The combined age-comorbidity score may be useful in some longitudinal studies to estimate relative risk of death from prognostic clinical covariates.

Supervised fitness walking in patients with osteoarthritis of the knee. A randomized, controlled trial.

OBJECTIVE To assess the effect of a program of supervised fitness walking and patient education on functional status, pain, and use of medication in patients with osteoarthritis of the knee. DESIGN An 8-week randomized, controlled trial. SETTING Inpatient and outpatient services of an orthopedic hospital in an academic medical center. PATIENTS A total of 102 patients with a documented diagnosis of primary osteoarthritis of one or both knees participated in the study. Data were obtained on 47 of 51 intervention patients and 45 of 51 control patients. INTERVENTIONS An 8-week program of supervised fitness walking and patient education or standard routine medical care. MEASUREMENTS Patients were evaluated and outcomes assessed before and after the intervention using a 6-minute test of walking distance and scores on the physical activity, arthritis impact, pain, and medication subscales of the Arthritis Impact Measurement Scale (AIMS). RESULTS Patients randomly assigned to the walking program had a 70-meter increase in walking distance relative to their baseline assessment, which represents an improvement of 18.4% (95% Cl, 9.8% to 27.0%). In contrast, controls showed a 17-meter decrease in walking distance relative to their baseline assessment (P less than 0.001). Improvements in functional status as measured by the AIMS physical activity subscale were also observed in the walking group but not in the control group (P less than 0.001); patients assigned to the walking program improved 39% (Cl, 15.6% to 60.4%). Although changes in scores on the arthritis impact subscale were similar in the two groups (P = 0.093), the walking group experienced a decrease in arthritis pain of 27% (Cl, 9.6% to 41.4%) (P = 0.003). Medication use was less frequent in the walking group than in the control group at the post-test (P = 0.08). CONCLUSIONS A program of supervised fitness walking and patient education can improve functional status without worsening pain or exacerbating arthritis-related symptoms in patients with osteoarthritis of the knee.

Improvement of outcomes after coronary artery bypass: A randomized trial comparing intraoperative high versus low mean arterial pressure

BACKGROUND The objective of this randomized clinical trial of elective coronary artery bypass grafting was to investigate whether intraoperative mean arterial pressure below autoregulatory limits of the coronary and cerebral circulations was a principal determinant of postoperative complications. The trial compared the impact of two strategies of hemodynamic management during cardiopulmonary bypass on outcome. Patients were randomized to a low mean arterial pressure of 50 to 60 mm Hg or a high mean arterial pressure of 80 to 100 mm Hg during cardiopulmonary bypass. METHODS A total of 248 patients undergoing primary, nonemergency coronary bypass were randomized to either low (n = 124) or high (n = 124) mean arterial pressure during cardiopulmonary bypass. The impact of the mean arterial pressure strategies on the following outcomes was assessed: mortality, cardiac morbidity, neurologic morbidity, cognitive deterioration, and changes in quality of life. All patients were observed prospectively to 6 months after the operation. RESULTS The overall incidence of combined cardiac and neurologic complications was significantly lower in the high pressure group at 4.8% than in the low pressure group at 12.9% (p = 0.026). For each of the individual outcomes, the trend favored the high pressure group. At 6 months after coronary bypass for the high and low pressure groups, respectively, total mortality rate was 1.6% versus 4.0%, stroke rate 2.4% versus 7.2%, and cardiac complication rate 2.4% versus 4.8%. Cognitive and functional status outcomes did not differ between the groups. CONCLUSION Higher mean arterial pressures during cardiopulmonary bypass can be achieved in a technically safe manner and effectively improve outcomes after coronary bypass.

The Charlson comorbidity index is adapted to predict costs of chronic disease in primary care patients

OBJECTIVE (1) To determine chronic illness costs for large cohort of primary care patients, (2) to develop prospective model predicting total costs over one year, using demographic and clinical information including widely used comorbidity index. STUDY DESIGN AND SETTING Data including diagnostic, medication, and resource utilization were obtained for 5,861 patients from practice-based computer system over a 1-year period beginning December 1, 1993, for retrospective analysis. Hospital cost data were obtained from hospital cost accounting system. RESULTS Average annual per patient cost was

Post‐Operative Delirium: Predictors and Prognosis in Elderly Orthopedic Patients

2,655. Older patients and those with Medicare or Medicaid had higher costs. Hospital costs were

Applying results of randomised trials to clinical practice: impact of losses before randomisation.

1,558, accounting for 58.7% of total costs. In the predictive model, individuals with higher comorbidity incurred exponentially higher annual costs, from

Severity of aortic atheromatous disease diagnosed by transesophageal echocardiography predicts stroke and other outcomes associated with coronary artery surgery: a prospective study.

4,317 with comorbidity score of two, to

Indications for total hip and total knee arthroplasties. Results of orthopaedic surveys.

5,986 with score of three, to

Effects of Depressive Symptoms on Health‐Related Quality of Life in Asthma Patients

13,326 with scores greater than seven. To use an adapted comorbidity index to predict total yearly costs, four conditions should be added to the index: hypertension, depression, and use of warfarin with a weight of one, skin ulcers/cellulitis, a weight of two. CONCLUSION The adapted comorbidity index can be used to predict resource utilization. Predictive models may help to identify targets for reducing high costs, by prospectively identifying those at high risk.

Identifying important predictors for anastomotic leak after colon and rectal resection: prospective study on 616 patients.

To compare the effect of post‐operative analgesia using epidural versus intravenous infusions on the incidence of delirium after bilateral knee replacement surgery in elderly patients. Additional risk factors and impact on post‐operative recovery were also assessed.