Incidence of note-leaving remains constant despite increasing suicide rates

Suicide notes (SN) are potentially valuable sources of information about the psychological states of the suicidal person. It was hypothesized that there was a significant relation between suicide rate and note-leaving rate and that the incidence of note-leaving was increased during prolonged economic recession. During 21 years (1981-2001) in Kobe, of a total of 18 558 violent deaths, 5161 were due to suicide (27.8%), with 3417 male cases (66.2%) and 1754 female cases (33.8%). For each year the annual suicide rates and note-leaving rates were calculated, and this represents the percentage of committed suicides in which SN were left, among all suicide victims. In spite of the prolonged economic slump, the note-leaving rate remained almost constant (23.4-36.2%). Pearson's correlation coefficient showed no significant correlation between suicide rate and note-leaving rates (r = 0.27, P = 0.23). The finding that the incidence of note-leaving remains constant despite increasing suicide rates may suggest that the reasons for suicide do not affect note-leaving. There are cross-cultural, ethnic, and racial variations in suicidal behaviors. Although this finding may be specific in Japan, further studies of SN are needed to help clarify the suicidal states of mind.