According to this study:

* A couple's same-cause death risk varies according to the cause of death.

In a large national study of the association between widowhood, specific causes of death, and influence on the surviving spouse's risk of death, researchers followed 373,189 elderly married couples in the United States from 1993 to 2002. Seventeen causes of death were studied, including infections and sepsis, various cancers, Alzheimer's and Parkinson's diseases, cardiovascular diseases, accidents or serious fractures, and chronic obstructive pulmonary disease (COPD).

The findings showed that the death of a spouse significantly increased the risk of death from any cause in the surviving spouse and also increased the risk of cause-specific death in men and women to varying degrees. A wife's death increased the cause-specific risk of death in men for 15 of 17 causes, with the risk exceeding 20% for COPD, diabetes, accidents or serious fractures, infections or sepsis, "all other known causes," and lung cancer. The death of a husband also increased a woman's risk of death for 15 causes, with a more than 20% higher risk of COPD, colon cancer, accidents or serious fractures, and lung cancer. Death caused by Alzheimer's disease and Parkinson's disease didn't significantly increase the risk of death in the surviving spouse of either sex.-JC