Ninety-one percent of those autopsied had underlying medical conditions, such as heart disease or respiratory disease, including asthma, before becoming ill with 2009 H1N1 influenza. Seventy-two percent of the adults and adolescents who died were obese. This finding agrees with earlier reports, based on hospital records, linking obesity with an increased risk of death from 2009 H1N1 influenza.
Yes. It seems that factors in addition to having H1N1 doomed these people.
OTOH, they say the H1N1 virus did itself cause tissue damage as was the case with the 1918 and 1957 strains.
It's still not decided why the 1918 flu was so deadly. It could be due to that particular flu or to other factors.