Given a passage with a context and an answer, construct a question on the basis of the information present in the passage. Construct the question in such a way that (i) it is unambiguous, (ii) it is answerable from the passage, (iii) its answer is unique (iv) it answer uses text phrases from the passage. Avoid creating questions that (i) can't be answered correctly without actually understanding the passage and (ii) uses the same words or phrases given in the passage.

[Q]: Context: Anemia is an established adverse risk factor in cardiovascular disease. However, the effect of preoperative anemia is not well defined in heart surgery. This study evaluates the effect of preoperative anemia on early clinical outcomes in patients undergoing cardiac surgery.', 'A retrospective, observational, cohort study of prospectively collected data was undertaken on 7,738 consecutive patients undergoing heart surgery between April 2003 and February 2009. Of these, 1,856 patients with preoperative anemia were compared to 5,882 patients without anemia (control group). According to the World Health Organization, anemia was defined as hemoglobin level\u2009<\u200913 g/dl for men and <12 g/dl for women. Selection bias not controlled by multivariable methods was assessed with propensity-adjustment method.', 'Overall mortality was 2.1%. Preoperative anemia was associated with tripling in the risk of death (4.6% vs 1.5%, p\u2009<\u20090.0001) and postoperative renal dysfunction (18.5% vs 6.5%, p\u2009<\u20090.0001). There was also a significant difference between the anemic and non-anemic group in the risk of postoperative stroke (1.9% vs 1.1%, p\u2009=\u20090.008), atrial fibrillation (36.7% vs 33%, p\u2009=\u20090.003) and length of hospital stay\u2009>\u20097 days (54% vs 36.7%, p\u2009<\u20090.0001). In propensity-adjusted, multivariable logistic regression, preoperative anemia was an independent predictor of mortality (odds ratio [OR] 1.44, 95% confidence interval [CI] 1.02 to 2.03), postoperative renal dysfunction (OR 1.73, 95% CI 1.43 to 2.1) and length of hospital stay\u2009>\u20097 days (OR 1.3, 95% CI 1.15 to 1.47).
Answer: In patients undergoing heart surgery, preoperative anemia is associated with an increased risk of mortality and postoperative morbidity.
[A]: Does preoperative anemia increase mortality and postoperative morbidity after cardiac surgery?


[Q]: Context: We quantitatively evaluated the collagen-to-smooth muscle tissue matrix ratio in ureteropelvic junction obstruction, and compared the ratio with the degree of obstruction, patient age and postoperative renal recovery.', "We analyzed histological sections from 65 patients with ureteropelvic junction obstruction and 6 normal controls. Morphological and functional grading systems were adapted to determine the degree of renal obstruction. To examine smooth muscle and collagen tissue, sections were stained using Masson's trichrome. Two distinct populations of collagen versus smooth muscle were identified and the tissue matrix ratio was calculated by color image analysis.", 'The mean tissue matrix ratio plus or minus standard deviation was 1.32+/-0.79 in all patients with ureteropelvic junction obstruction but only 0.30+/-0.10 in normal controls (p <0.0001). It appeared that the lower the tissue matrix ratio, the better the improvement in postoperative hydronephrosis (r = -0.50, p = 0.0001). Better recovery of renal function after pyeloplasty was observed with a decrease in the tissue matrix ratio (r = -0.43, p = 0.0004). We divided patients according to the tissue matrix ratio into groups 1--ratio 1 or less, 2--greater than 1 to 1.5 and 3--greater than 1.5 to determine a more detailed and clinically applicable correlation of tissue matrix ratio with postoperative renal functional changes. Better improvement in postoperative renal function was observed in group 1 than in group 3 (p = 0.002). Also, the tissue matrix ratio increased with patient age (r = 0.33, p = 0.007).
Answer: Since our data represent an objective and quantitative parameter associated with ureteropelvic junction obstruction, we believe that our findings may help to predict the prognosis after pyeloplasty.
[A]: Does collagen-to-smooth muscle ratio help prediction of prognosis after pyeloplasty?


[Q]: Context: The aim of the present study was to evaluate whether thyroid hormonal changes during menopause may affect the development and the course of major depressive disorder.', 'Thirty-nine female patients (n = 17 in pre-menopause; n = 22 in post-menopause) with major depressive disorder based on Diagnostic Statistical Manual of Mental Disorders (4th edition) criteria and who were euthyroid and not on hormonal replacement therapy, participated in a prospective, 6-week, open-label naturalistic study. The Hamilton Depression Rating Scale-17 item, the Montgomery-Asberg Depression Rating Scale, the Clinical Global Impression scale and the Cognitive Failure Questionnaire were administered at baseline, week 1, week 3, and week 6. Levels of thyroid stimulating hormone, total thyroxine and total triiodothyronine were collected at baseline visit.', 'In the whole sample, particularly in pre-menopausal women, levels of thyroid stimulating hormone-potential markers of subclinical hypothyroidism were correlated with those of less severe but more resistant depressive form. Conversely, total thyroxine levels were correlated with a more severe depression, but high levels of this hormone favored the response to antidepressants. Overall, a diagnosis of subclinical hypothyroidism was associated with a poor response to antidepressant treatment. Finally, total triiodothyronine levels were associated with better cognitive functioning, though they did not influence improvement occurring with recovery.
Answer: Our study suggests that thyroid hormones may have an impact on severity and efficacy of antidepressant treatment. However, our result should be considered with caution and merely as a suggestion due to some methodological limitations. Hence further studies are required to better ascertain the role of thyroid hormones in depression after menopause.
[A]:
Do thyroid hormones affect recovery from depression during antidepressant treatment?