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.

Example Input: Context: To assess the effects of treatment with antitumour necrosis factor (TNF) agents, methotrexate, or other non-biological disease-modifying antirheumatic drugs (DMARDs) on cardiovascular event risks among patients with rheumatoid arthritis (RA).', "We conducted a retrospective study using data from the MarketScan claims database. Patients with RA with ≥1 prescription for an index drug were included. Each patient's use of an index drug was calculated cumulatively as a time-varying exposure. The incidence of cardiovascular events among patients with RA was determined. Associations between drug exposures and occurrence of cardiovascular events were assessed with Cox proportional hazards models.", 'Of 113\u2005677 patients identified, 35.8%, 41.1% and 23.1% received anti-TNF agents, methotrexate and other DMARDs, respectively. Patients were treated for an average of 7.6\u2005months; 2138 patients (1.9%) had a cardiovascular event following their index prescription. Each additional 6\u2005months of anti-TNF therapy use versus non-use reduced the risk (HR; 95% CI) for any cardiovascular event by 12% (0.88; 0.81 to 0.95, p=0.002). Anti-TNF therapy was associated with a 13% and 12% reduction in cardiovascular events in patients aged ≥50\u2005years (0.87; 0.80 to 0.95, p=0.002) and in those without prior methotrexate use (0.88; 0.78 to 0.99, p=0.04), respectively. Cumulative use of 1, 2 or 3\u2005years of anti-TNF therapy versus non-use is expected to reduce cardiovascular event risks by 21%, 38% and 51%, respectively.
Answer: Anti-TNF therapy was associated with a significantly lower risk of cardiovascular events among patients with RA, older patients with RA and patients without prior exposure to methotrexate.
Example Output: Are longer durations of antitumour necrosis factor treatment associated with reduced risk of cardiovascular events in patients with rheumatoid arthritis?

Example Input: Context: Among factors that may affect the potency of botulinum toxin A (Botox), it is said that foam, together with bubbles, may cause surface denaturation of the toxin.', 'To determine whether the muscle relaxation effect of Botox is preserved and has the same duration when it is reconstituted in the presence of foam.', 'Six female volunteers, aged 42 to 56 years old, were treated for glabellar and periocular wrinkles. Each half of the face was treated with 16 U of Botox divided in four sites: three at the lateral orbital area and one at the medial brow, in the glabellar region. The right side received Botox gently reconstituted with saline to avoid foaming formation. The left side of the face was treated with Botox that was rapidly reconstituted in order to achieve as many bubbles as possible, even with shaking. Blinded observers compared pretreatment and posttreatment photographs and answered assessment-related questions. The results were analyzed clinically and statistically.', 'There was no difference in muscle paralysis between treated sides in all patients, neither in early (15 days) nor late (4 months) follow-up evaluations.
Answer: Botox maintains its potency even in the presence of foaming during the reconstitution process.
Example Output: Does foam during reconstitution affect the potency of botulinum toxin type A?

Example Input: Context: Visit-to-visit variability in low-density lipoprotein-cholesterol (LDL-C) was found to be a novel predictor of adverse cardiac events. Obstructive sleep apnea (OSA), an emerging cardiovascular risk factor, is characterized by sympathetic activation and increased oxidative stress which are regulators of LDL-C metabolism. We hypothesized that OSA was associated with LDL-C variability.', 'We prospectively recruited 190 patients with coronary artery disease for an overnight sleep study. Statin was prescribed upon discharge for 186 patients. Serum LDL-C levels were measured at clinic every 3 to 6\xa0months. Severity of OSA (on the basis of apnea-hypopnea index (AHI)) was correlated with visit-to-visit LDL-C variability (on the basis of variation independent of mean (VIM)) in outpatient clinic.', "The mean AHI was 21.9\u2009±\u200918.9. Using an AHI cut-off of 5-14.9, 15-29.9, and ≥30, the prevalence of mild, moderate, and severe OSA was 26.3, 18.9, and 27.4\xa0%, respectively. After 53.2\u2009±\u200925.3\xa0months, LDL-C was recorded over 8.1\u2009±\u20094.2 measurements. VIM positively correlated with AHI (Pearson's r\u2009=\u20090.183, p\u2009=\u20090.016), but not body mass index, baseline and mean follow-up LDL-C levels, and number of LDL-C measurements. In multiple linear regression analysis, AHI remained an independent predictor of VIM after adjusting for diabetes mellitus and hyperlipidemia. A 10-unit rise in AHI led to a 3.8\xa0% increase in VIM (95\xa0% CI 0.1 to 7.4\xa0%; p\u2009=\u20090.044).
Answer: This is the first study to show the independent correlation between OSA severity and visit-to-visit LDL-C variability. Our finding contributes to the understanding of the vasculopathic effects of OSA.
Example Output:
Is obstructive sleep apnea associated with visit-to-visit variability in low-density lipoprotein-cholesterol in patients with coronary artery disease?