Concerning the general mature population, the combination of vulnerability (‘frailty’) and multimorbidity is rarely seen: only six in one hundred adults are frail and are multimorbid, according to an analysis including 14,704 subjects. Nearly half of the population was not frail and did not possess multimorbidity. Approximately forty percent were multimorbid but not frail, and three percent was just frail, but without multimorbidity.
Frail, elderly participants however were at risk for multimorbidity: seven in ten suffered from multiple diseases. On the other hand, in the opposite direction this was not the case: less than twenty percent of the multimorbid group was defined as frail.
Based on three longitudinal studies, the researchers were not able to conclusively determine whether frailty contributes to the development of multimorbidity or vice versa. However, should there be a causal association between the two conditions, it will most likely work in both ways. The results of the first two studies appear to verify the contribution of multimorbidity to frailty; the third study in provided evidence for frailty as a prognostic factor for multimorbidity.