Task and barrier self-efficacy among treatment-seeking smokers with current, past or no psychiatric diagnosis.

OBJECTIVE: Individuals with a lifetime diagnosis of mental illness smoke at rates greater than the general population, and have more difficulty quitting. Cessation self-efficacy has been linked with positive cessation outcomes and can be assessed as either task (confidence to quit) or barrier self-efficacy (confidence to quit in the face of obstacles). We investigated differences in self-efficacy among smokers with a current, past or no lifetime diagnosis of psychiatric illness. METHODS: 737 treatment-seeking smokers provided demographic info and smoking history, and were assessed for nicotine dependence, motivation to quit, and task and barrier self-efficacy (Smoking Self-Efficacy Questionnaire; SEQ-12) for smoking cessation. Current and past psychiatric diagnoses were assessed with the Mini International Psychiatric Interview (M.I.N.I. 6.0). ANOVA, chi-square and correlations were calculated for the smoking-related variables across the psychiatric categories. RESULTS: Those with a current diagnosis smoked more cigarettes and were highly nicotine dependent. These individuals had lower barrier self-efficacy compared to those with past or no diagnosis; no differences between groups were observed on task self-efficacy. Motivation to quit was significantly correlated with task self-efficacy in all 3 groups, but with barrier-self efficacy only among those with no lifetime diagnosis of psychiatric illness. CONCLUSION: Our results highlight the differences in task and barrier cessation self-efficacy in treatment-seeking smokers. Those with a current psychiatric diagnosis have less confidence in their ability to quit when confronting barriers, especially those reflecting internal states. These results highlight the need for targeted interventions to improve cessation self-efficacy, an important determinant of health behavior change.

Comparative clinical outcomes with St. Jude Medical, Medtronic Hall and CarboMedics mechanical heart valves.

BACKGROUND AND AIM OF THE STUDY: Whether the St. Jude Medical (SJM), Medtronic Hall (MH) or CarboMedics (CM) heart valves confer any relative benefits to patient outcome remains controversial. While numerous studies have analyzed clinical results with a single brand, and a few studies have compared two brands, there are no single-center trials comparing all three valves. METHODS: Our experience with patients who had either a SJM, MH or CM mechanical valve in isolated aortic valve (AVR) or mitral valve (MVR) replacement was reviewed. AVR was performed in 953 patients (SJM = 394, MH = 314, CM = 245) and MVR in 591 patients (SJM = 193, MH = 264, CM = 134). Survivors were assessed annually; follow up consisted of 3336 patient-years (pt-yr) after AVR and 1693 pt-yr after MVR. RESULTS: Preoperatively, in the AVR group, more MH patients had previous valve surgery (p = 0.001) or were in NYHA class III/IV (p = 0.03), and more CM patients had a concomitant surgical procedure (p = 0.005). The hospital mortality after AVR with SJM, MH and CM valves was 3.8, 4.7 and 5.3%, respectively (p = 0.65). In the MVR group, there were more males in the CM group (p = 0.011), more CM patients had concomitant surgery (p = 0.001), and more MH patients had previous surgery (p = 0.006). The hospital mortality after MVR with SJM, MH and CM valves was 8.3, 10.2 and 6.0%, respectively (p = 0.35). There was no late survival advantage in either the AVR or MVR group according to the valve used (p = 0.24 and p = 0.90, respectively). For the AVR group the five-year actuarial freedom from thromboembolism was: SJM 85.8 +/- 2.5%, MH 80.1 +/- 2.7% and CM 85.9 +/- 3.5% (p = 0.04), and for MVR it was: SJM 84.2 +/- 4.0%, MH 77.5 +/- 3.4% and CM 86.9 +/- 5.2% (p = 0.27). Bleeding occurred with a similar frequency in the AVR (p = 0.36) and MVR (p = 0.70) groups. No cases of structural failure were identified in this study. At follow up, among AVR patients NYHA class III/IV was present in: SJM 5%, MH 6% and CM 3% (p = 0.50), while among MVR patients this was identified in: SJM 7%, MH 10% and CM 4% (p = 0.22). CONCLUSION: It is concluded that the SJM, MH and CM mechanical valves offer similar clinical results when used for isolated AVR or MVR. While there is a suggestion of an advantage with bileaflet valves, any differences detected may simply reflect differences in the preoperative patient variables.

Gender differences in predictors for long-term smoking cessation following physician advice and nicotine replacement therapy.

We evaluated gender differences in demographic, smoking history, nicotine dependence, transtheoretical, and perceived stress variables as predictors of smoking cessation. Participants (n = 381) smoked at least 15 cigarettes per day and were motivated to quit. The outcome variable was 7-day abstinence at 1-year follow-up. Predictor variables included: age, education level, number of years smoking, cigarettes per day, quit attempts, nicotine dependence, stage of change, decisional balance, processes of change, self-efficacy, and perceived stress. Logistic regression analysis was used to derive predictive models for women and men. In women, lower scores for pre- and mid-treatment perceived stress significantly increased the likelihood of being abstinent at follow-up. For men, a higher level of education or number of quit attempts lasting > 24 hours in the past year, along with less frequent use of behavioural processes of change at baseline increased the probability of being abstinent at follow-up.

Human skeletal muscle exercise metabolism following an expedition to mount denali.

Chronic exposure to high altitude is known to result in changes in the mechanisms regulating O(2) delivery to the contracting muscle. However, the effects of acclimatization on metabolism in the contracting muscle cell remain unclear. In this study, we have investigated the hypothesis that acclimatization would result in a closer coupling between ATP utilization and ATP production and that the improved energy state would be accompanied by a reorganization of the metabolic pathways consisting of an increased oxidative and decreased glycolytic potential. Five men, mean age of 28 +/- 2 (SE) yr, performed a standardized, two-stage submaximal cycling task in normoxia for 20 min at each of 59 and 74% peak O(2) consumption before and 3-4 days after returning from a 21-day expedition to Mount Denali (6,194 m). Acclimatization was without effect in altering the resting values of the adenine nucleotides (ATP, ADP, AMP), inosine monophosphate (IMP), or phosphocreatine (PCr) in the vastus lateralis. During exercise (40 min) after acclimatization compared with preacclimatization, PCr was not as depressed (33.2 +/- 7.1 vs. 40.6 +/- 5.4 mmol/kg dry wt) and IMP (0.289 +/- 0.11 vs. 0. 131 +/- 0.03 mmol/kg dry wt) and lactate (26.1 +/- 6.2 vs. 18.6 +/- 8.8 mmol/kg dry wt) in contracting muscle were not as elevated (P < 0.05). Although no effect of acclimatization was observed for the maximal activity (mol. kg protein(-1). h(-1)) of citrate synthase (4. 76 +/- 0.44 vs. 4.94 +/- 0.45), lactate dehydrogenase was increased by 13% (36.5 +/- 2.6 vs. 41.2 +/- 3.1, P < 0.05). It is concluded that acclimatization results in an improved energy state in the contracting muscle when tested under normoxic conditions; however, these effects are not associated with a higher oxidative potential or a lower glycolytic potential as hypothesized.

Downregulation in muscle Na(+)-K(+)-ATPase following a 21-day expedition to 6,194 m.

To investigate the hypothesis that acclimatization to altitude would result in a downregulation in muscle Na(+)-K(+)-ATPase pump concentration, tissue samples were obtained from the vastus lateralis muscle of six volunteers (5 males and 1 female), ranging in age from 24 to 35 yr, both before and within 3 days after a 21-day expedition to the summit of Mount Denali, Alaska (6,194 m). Na(+)-K(+)-ATPase, measured by the [(3)H]ouabain-binding technique, decreased by 13.8% [348 +/- 12 vs. 300 +/- 7.6 (SE) pmol/g wet wt; P < 0.05]. No changes were found in the maximal activities (mol. kg protein(-1). h(-1)) of the mitochondrial enzymes, succinic dehydrogenase (3.63 +/- 0.20 vs. 3.25 +/- 0.23), citrate synthase (4. 76 +/- 0.44 vs. 4.94 +/- 0.44), and malate dehydrogenase (12.6 +/- 1. 8 vs. 12.7 +/- 1.2). Similarly, the expedition had no effect on any of the histochemical properties examined, namely fiber-type distribution (types I, IIA, IIB, IC, IIC, IIAB), area, capillarization, and succinic dehydrogenase activity. Peak aerobic power (52.3 +/- 2.1 vs. 50.6 +/- 1.9 ml. kg(-1). min(-1)) and body mass (76.9 +/- 3.7 vs. 75.5 +/- 2.9 kg) were also unaffected. We concluded that acclimatization to altitude results in a downregulation in muscle Na(+)-K(+)-ATPase pump concentration, which occurs without changes in oxidative potential and other fiber-type histochemical properties.

Effects of a 21-day expedition to 6,194 m on human skeletal muscle SR Ca2+-ATPase.

We investigated the effects of a 21-day expedition to the summit of Mount Denali, Alaska (6,194 m) on selected Ca2+ sequestration properties of sarcoplasmic reticulum (SR) calcium pump in vastus lateralis muscle. Muscle samples were obtained by biopsy from 5 male climbers (peak oxygen consumption, VO2peak = 52.3 +/- 2.1 mL.kg(-1).min(-1)) approximately 7 days prior to (PRE) and 4 days following (POST) the expedition. A comparison of PRE versus POST measures of maximal Ca2+-ATPase activities (117 +/- 8.5 vs. 97.6 +/- 5.6 nmol.mg protein(-1).min(-1)) and Ca2+-uptake (204 +/- 15 vs. 161 +/- 11 nmol.mg protein(-1).min(-1)) measured in crude homogenates obtained from pre-exercised muscle, indicated only an effect (p < 0.05) of the expedition on Ca2+-uptake. The reduction in Ca2+-ATPase activity, representing 16.6%, was not significant (p = 0.089). The sarco endoplasmic reticulum calcium (SERCA)-ATPase isoforms, measured using Western blotting techniques, revealed a small reduction (p < 0.05) in SERCA 1 (-4.6 +/- 1.9%), but not in SERCA 2a (+2.0 +/- 1.4%). Prior to the expedition, both Ca2+-ATPase activity and Ca2+-uptake were reduced (p < 0.05) by approximately 34 and 18%, respectively, following 40 min of a two-step continuous cycling task (20 min at 59% VO2peak and 20 min at 74% VO2peak). The exercise-induced reduction in Ca2+-ATPase activity was independent of fiber type. Only in the case of Ca2+-uptake was a lower exercise response (p < 0.05) observed following the expedition, an effect that was due to the lower resting value. It is concluded that acclimatization as experienced during a mountaineering expedition induces changes in the properties of the SR Ca2+-pump, and particularly to Ca2+-sequestering function.

Determinants of hospital survival following reoperative single valve replacement.

OBJECTIVE: To determine the indicators of risk for hospital death, patients undergoing reoperative valve replacement were analyzed METHODS: Four hundred and eighteen consecutive patients undergoing reoperative valve replacement from 1977 to 1994 were reviewed using univariate and multivariate analysis. RESULTS: Overall hospital mortality was 11.2% with 9.4% mortality with aortic valve replacement and 14.2% with mitral valve replacement (P=0.52). Mortality was 9.7% for patients less than 70 years of age compared with 19.4% for older patients (P=0.03), and was 8.5% for those with anoxia times less than 90 mins versus 21.9% for those with longer anoxia times (P=0.001). For first reoperations, 9.5% of patients died, while for patients undergoing second or more reoperation, mortality was 23.2% (P=0.01). While mortality increased from 8.9% to 19.0% with the addition of a concomitant procedure (P=0.008), it was not affected if the additional procedure was a coronary bypass (P=0. 96). The indication for surgery influenced outcome. Mortality was zero for thromboembolism, 9% for structural failure, 23% for nonstructural failure and 22% for endocarditis (P=0.006). For New York Heart Association (NYHA) functional class I patients, mortality was 1.6% compared with 22.3% for those in NYHA class IV (P=0.006). By multivariate analysis, however, only the indication for surgery and the NYHA functional class influenced survival. CONCLUSIONS: Reoperative valve surgery can be performed with a survival (88.8%) that is similar to the initial procedure (91.2%). The indication for surgery and NYHA functional class alone influenced outcome; therefore, possible early reoperation is indicated before clinical deterioration occurs.

Is telephone counselling a useful addition to physician advice and nicotine replacement therapy in helping patients to stop smoking? A randomized controlled trial.

BACKGROUND: The authors evaluated the incremental efficacy of telephone counselling by a nurse in addition to physician advice and nicotine replacement therapy in helping patients to stop smoking. METHODS: The trial was conducted at the University of Ottawa Heart Institute. A total of 396 volunteers who smoked 15 or more cigarettes daily were randomly assigned to either of 2 groups: usual care (control group) and usual care plus telephone counselling (intervention group); the groups were stratified by sex and degree of nicotine dependence. Usual care involved the receipt of physician advice on 3 occasions, self-help materials and 12 weeks of nicotine replacement therapy. Telephone counselling was provided by a nurse at 2, 6 and 13 weeks after the target quit date. Point-prevalent quit rates were determined at 52 weeks after the target quit date. RESULTS: The point-prevalent quit rates at 52 weeks did not differ significantly between the control and intervention groups (24.1% v. 23.4% respectively). The quit rates did not differ significantly at the secondary measurement points of 4, 12 and 26 weeks. INTERPRETATION: Brief physician assistance, along with nicotine replacement therapy, can help well-motivated smokers to quit. Three additional sessions of telephone counselling by a nurse were ineffective in increasing quit rates. This form of assistance may be useful in the absence of physician advice or when self-selected by patients.

Are older patients with mechanical heart valves at increased risk?

BACKGROUND: Controversy exists regarding the use of mechanical valves in older patients. Many authorities believe that the use of anticoagulants in the elderly is associated with an increased risk of warfarin-related complications. Therefore, we compared the results with mechanical valves in older patients to a cohort of younger patients. METHODS: Aortic (AVR) or mitral valve replacement (MVR) with a mechanical valve was performed in 1,245 consecutive patients who were followed prospectively. They were grouped by age (group 1, < or = 65 years; group 2, > 65 years). The study groups consisted of AVR (group 1, 459 patients; group 2, 323 patients) MVR (group 1, 313 patients; group 2, 150 patients). RESULTS: The average age for the groups was: AVR (group 1, 51 years; group 2, 70 years; p = 0.03) and MVR (group 1, 53 years; group 2, 70 years; p = 0.03). For AVR the incidence of thromboembolism was 0.050 (group 1) and 0.038 (group 2) (p = 0.37) and the actuarial freedom from thromboembolism was 83.0%+/-3.0% and 86.5%+/-1.0%, respectively (p = 0.13). The incidence of bleeding after AVR was 0.021 for group 1 and 0.028 for group 2 (p = 0.49). For MVR the incidence of thromboembolism was 0.059 for group 1 and 0.051 for group 2 (p = 0.75) and the actuarial freedom from thromboembolism was 78.8%+/-3.0% and 75.4%+/-8.7%, respectively (p = 0.71). The incidence of bleeding after MVR was 0.020 for group 1 and 0.027 for group 2 (p = 0.62). CONCLUSIONS: Mechanical valves perform well in selected older patients with no increased risk of bleeding or thromboembolism.

Coagulation factor changes following endurance exercise.

OBJECTIVE: To compare preexercise with immediate and 24 h postvalues of coagulation parameters in experienced athletes following a single, 42-km marathon run. DESIGN: Blood samples were taken 18 h before, immediately after, and 24 h after a marathon race from 14 well-trained individuals, and coagulation factors were measured. SETTING: The setting was a 42-km race on a cloudy day in May with an ambient temperature of 22 degrees C. SUBJECTS: The subjects were fourteen normal healthy individuals (12 men and 2 women) who regularly participated in runs of at least 20 km each week. INTERVENTION: The subjects all undertook a 42-km marathon run followed by a 24-h rest period and a repeat assessment. MAIN OUTCOME MEASURES: Coagulation factors including factor VIII (FVIII) and von Willebrand factor (vWF) were measured, as was the platelet response to aggregating agents. These responses are all considered as primary outcome measures of hypercoagulability and reflect the prethrombotic state. RESULTS: The hematocrit was not altered immediately after the race, but the platelet count (mean +/- SD) was significantly elevated (p < 0.05) to 322 +/- 54 x 10(9)/L from 256 +/- 70 x 10(9)/L, and the mean platelet size increased by 24 h (p < 0.05). Platelet aggregation in response to epinephrine, adenosine diphosphate, and collagen was decreased by 40%, 15%, and 60%, respectively, at 24 h; the response to ristocetin was only slightly (10%) altered. There was a significant elevation of beta-thromboglobulin in the plasma at the end of the race, and this elevation persisted for 24 h, indicating considerable release from the platelet alpha granules. The effect on platelet function was further demonstrated by a decrease in the quantity of glycoprotein Ib at 24 h, but not immediately after the race. There was an approximately 300% increase in the levels of FVIII, vWF antigen (vWF:Ag), and ristocetin cofactor activity. In addition, the normal vWF:Ag multimer pattern was changed in the samples taken immediately after the race. CONCLUSIONS: The data support the evidence of significant alteration of certain factors that are involved in coagulation following endurance exercise. Increases in FVIII and vWF are also noted in some prethrombotic conditions. The decreased platelet aggregation suggests early activation during the period of exercise.

Tobacco addiction and hypertension.

The significance of smoking in the hypertensive patient may be unappreciated. The risk of hypertension may be tripled in such patients. Tobacco addiction may also compromise the treatment of hypertensives. The importance of smoking cessation for hypertensive smokers cannot be overemphasized and should be seen as fundamental. Nicotine replacement therapy (NRT), when used appropriately, can enhance the likelihood of cessation. All smokers, but particularly hypertensive smokers, should be advised to quit and offered specific and ongoing assistance in this respect.

Comparative results with the St. Jude Medical and Medtronic Hall mechanical valves.

This study compared the clinical performance of the St. Jude Medical and Medtronic Hall mechanical valves in isolated aortic or mitral valve replacement. From 1984 to 1993, 349 St. Jude Medical valves (aortic 237, mitral 112) and 465 Medtronic Hall valves (aortic 272, mitral 193) were implanted in 814 patients at the University of Ottawa Heart Institute. The patients had similar preoperative characteristics. The hospital mortality rate for aortic valve replacement was 3.4% with the St. Jude Medical valve and 5.8% with the Medtronic Hall valve (p = 0.26) and the rate for mitral valve replacement was 8.9% with the St. Jude Medical valve and 11.9% with the Medtronic Hall valve (p = 0.54). Actuarial estimates of survival and freedom from complications were calculated. At 5 years the actuarial probability of survival (including hospital deaths) for aortic valve replacement was 86% +/- 3% with the St. Jude Medical valve and 68% +/- 4% with the Medtronic Hall valve (p = 0.0001) and for mitral valve replacement was 75% +/- 7% with the St. Jude Medical valve and 70% +/- 4% with the Medtronic Hall valve (p = 0.54). The most common cause of late death was cardiac failure and no deaths were caused by structural failure. The 5-year probability of freedom from bleeding after aortic valve replacement was 99% +/- 1% with the St. Jude Medical valve and 95% +/- 2% with the Medtronic Hall valve (p = 0.06) and after mitral valve replacement 99% +/- 1% with the St. Jude Medical valve and 97% +/- 2% with the Medtronic Hall valve (p = 0.37). The 5-year probability of freedom from thromboembolism after aortic valve replacement was 88% +/- 4% with the St. Jude Medical valve and 81% +/- 3% with the Medtronic Hall valve (p = 0.08) and after mitral valve replacement was 85% +/- 7% with the St. Jude Medical valve and 77% +/- 5% with the Medtronic Hall valve (p = 0.17). Reoperation was uncommon and there were no cases of structural valve failure. The 5-year actuarial estimate of freedom from reoperation therefore for aortic valve replacement was 99% +/- 1% with the St. Jude Medical valve and 96% +/- 2% with the Medtronic Hall valve (p = 0.09) and for mitral valve replacement was 98% +/- 2% with the St. Jude Medical valve and 95% +/- 3% with the Medtronic Hall valve (p = 0.40).(ABSTRACT TRUNCATED AT 400 WORDS)

Long-term experience with the Ionescu-Shiley pericardial valve.

To determine the long-term durability of the Ionescu-Shiley valve, we analyzed our experience with this valve at the University of Ottawa Heart Institute. To 1988, 780 patients have had aortic valve replacement (AVR = 528) or mitral valve replacement (MVR = 252). Of the aortic valves, 310 were standard profile and 218 were low profile. Of the mitral valves, 143 were standard profile and 109 were low profile. Actuarial survival at 10 years was as follows: AVR, 62% +/- 3%; MVR, 58% +/- 4%; p = 0.42. At 14 years, the results were AVR, 44% +/- 1% and MVR, 46% +/- 5%; p = 0.40. Reoperation was required in 197 patients. Structural failure was present in 85% of these valves, with leaflet tears alone in 69%, tears with calcification in 21%, and calcification alone in 10%. Leaflet tears occurred in 95% after AVR and in 78% after MVR (p = 0.006) and were seen in 95% of low-profile valves and 87% of standard-profile valves (p = 0.16). The actuarial freedom from reoperation at 10 years was: AVR, 58% +/- 3%; MVR, 62% +/- 5%; p = 0.49. At 13 years, these rates were 38% +/- 4% for AVR and 25% +/- 9% for MVR (p = 0.79). For AVR, the 10-year rate of freedom from reoperation was 57% +/- 4% for standard-profile valves and 57% +/- 8% for low-profile valves (p = 1.0). Similarly for MVR, the 10-year freedom from reoperation was 61% +/- 6% for standard-profile valves and 68% +/- 8% for low-profile valves.(ABSTRACT TRUNCATED AT 250 WORDS)