Researchers, writing in the journal Heart, pooled data from 23 studies and found that social isolation or feelings of loneliness were tied to an increased risk for coronary heart disease (冠心病 ) and strokes.

The studies included data from 181,006 men and women ages 18 and over. There were 4,628 coronary events and 3,002 strokes in follow-up periods【C1】_____from three to 21 years. Three of the papers【C2】__loneliness, 18 looked at social isolation and two included both. Social isolation and loneliness were determined with questionnaires; the researchers depended on medical records and death【C3】_____for determining coronary events and strokes.

The scientists found that loneliness and social isolation increased the【C4】_____risk of having a heart attack or a death from heart disease by 29 percent, and the risk of stroke by 32 percent. There were no【C5】_____between men and women.

“People have tended to focus from a policy point of view on【C6】_____lonely people to make them more【C7】__,” said the lead author, Nicole K. Valtorta, a research fellow at the University of York in England. “Our study【C8】_____that if this is a risk factor, then we should be trying to prevent the risk factor in the first place.”

The authors【C9】_____that this was a review of observational studies and did not【C10】_____cause and effect.

A) acknowledge E) differences I) narrow M) relative

B) certificates F) establish J) permanent N) submitting

C) connected G) formats K) produces O) targeting

D) demonstrates H) measured L) ranging

【C4】