Being married may improve the odds of a good recovery after surgery, according to a new report.

The study, in JAMA Surgery, included 1,567 people 50 and older who underwent cardiac operations — 1,026 married, 184 divorced or separated, 331 widowed and 35 never married. The researchers collected information on whether they needed help before their operations in six activities of daily living: dressing, walking, bathing, eating, toileting or getting in and out of bed. They interviewed them (or their survivors) two years after surgery.

About 20 percent of married patients had either died or developed a new dependency within two years of their operations. But 28.8 percent of divorced or separated people and 33.8 percent of the widowed had these negative outcomes.

Even after controlling for age, sex, smoking and other factors, compared with people who were married, the divorced, separated or widowed were at least 40 percent more likely to have died or acquired a new disability.