Changes over time in the effect of marital status on cancer survival

Discrete-time hazard regression models for cancer deaths among more than 440 000 women and men diagnosed with cancer 1970-2007 at age 30-89 were estimated, using register data encompassing the entire Norwegian population. More than 200 000 cancer deaths during over 2 million person-years of exposure were analyzed.The excess mortality of the never-married compared to the married has increased steadily for men, in particular the elderly. Among elderly women, the excess mortality of the never-married compared to the married has increased, and there are indications of an increasing excess mortality of the widowed. The excess mortality of divorced men and women, however, has been stable.There is no obvious explanation for the increasing disadvantage among the never-married. It could be due to a relatively poorer general health at time of diagnosis, either because of a more protective effect of partnership in a society that may have become less cohesive or because of more positive selection into marriage. Alternatively, it could be related to increasing differentials with respect to treatment. Today's complex cancer therapy regimens may be more difficult for never-married to follow, and health care interventions directed and adapted more specifically to the broad subgroup of never-married patients might be warranted.It is well known that all-cause mortality rates are higher among the unmarried, especially the never-married, than among the married [1]. A similar pattern is also found for cause-specific mortality [2-4]. In particular, unmarried individuals are overrepresented regarding violent deaths, and also have a considerable excess mortality from lifestyle-related disorders, such as cardiovascular disease.During the last decade, a number of studies have shown that also prognosis following a cancer diagnosis is influenced by marital status [5,6]. This is presumably partly due to a poorer overall health at time of diagnosis in the unmarried population compared to the mar