Glutathione S-transferases and esterases in placenta after normal and pre-eclamptic pregnancies.

Severe pre-eclampsia reduced significantly (P<0.05) by 68+/-6 per cent (mean+/-sem, n=10) the maximal velocity (V(max)) and, consequently, reduced significantly by 60+/-7 per cent the catalytic efficiency (C(E)) of placental glutathione transferase pi, assayed with ethacrynic acid. Mild and severe pre-eclampsia reduced significantly by 82+/-5 per cent (mean+/-sem, n=5) and by 41+/-5 per cent (mean+/-sem, n=10), respectively, the V(max)and, consequently, reduced significantly by 72+/-7 and by 33+/-13 per cent, respectively, the C(E)of esterase, assayed with p-nitrophenyl acetate. Furthermore, severe pre-eclampsia increased significantly by 296+/-78 per cent the Michaelis-Menten constant (K(m)) of total GST, assayed with chlorodinitrobenzene and, consequently, decreased significantly the C(E)by 83+/-3 per cent. On the other hand, the concentrations of total and non-protein thiols did not change significantly in placental homogenates from patients with mild or severe pre-eclampsia compared to normal pregnancies. These findings would indicate a decreased capacity of the glutathione transferases and esterase detoxification systems to protect the fetus from drugs prescribed to pregnant women suffering pre-eclampsia, mainly in the severe phase.

Willingness to pay: a valid and reliable measure of health state preference?

The development of methods to measure willingness to pay (WTP) has renewed interest in cost-benefit analysis (CBA) for the economic evaluation of health care programs. The authors studied the construct validity and test-retest reliability of WTP as a measure of health state preferences in a survey of 102 persons (mean age 62 years; 54% male) who had chronic lung disease (forced expiratory volume < 70%). Interview measurements included self-reported symptoms, the oxygen-cost diagram for dyspnea, Short-Form 36 for general health status, rating scale and standard gamble for value and utility of current health state relative to death and healthy lung functioning, and WTP for a hypothetical intervention offering a 99% chance of healthy lung functioning and a 1% chance of death. WTP was elicited by a simple bidding game. To test for starting-point bias, the respondents were randomly assigned to one of five starting bids. All health status and preference measurements except WTP (controlling for income) showed significant (p < 0.05) difference between disease-severity groups (mild/moderate/severe). WTP was significantly (p = 0.01) associated with household income, but other health status and preference measure were not. The measure most highly correlated with WTP was standard gamble (r = -0.46). There was no association between starting bid and mean WTP adjusted for income and health status. The test-retest reliability of WTP was acceptable (r = 0.66) but lower than that for the standard gamble (r = 0.82).(ABSTRACT TRUNCATED AT 250 WORDS)

Relationship between symptoms and health-related quality of life in chronic lung disease.

The authors studied the relationship between patient self-reported symptoms and responses to a general measure of health-related quality of life [Short Form 36 (SF-36)] for 102 patients who had chronic lung disease [forced expiratory volume in one second (FEV1) < 70%]. The primary diagnoses were chronic bronchitis, emphysema, and asthma; the mean age was 62 years, and 46% were women. Based upon Medical Research Council (MRC) symptom scores, the patients' disease severity was classified as mild (21%), moderate (22%), or severe (57%). The SF-36 scores differed significantly between disease severity groups in domains of health perception, physical functioning, physical role, and energy. The SF-36 physical functioning and Oxygen Cost Diagram scores correlated well (r = 0.78). The authors conclude that SF-36 is a useful and valid measure of general health status in patients with chronic lung disorders.