The survival curves of both the high-score (χ = 4.5, P = 0.034) and middle-score groups (χ = 5.0, P = 0.026) of intellectual activity were significantly higher than those of the low-score group.
Similarly, mortality from respiratory disease was lowest in the high-score groups for total functional capacity, instrumental self-maintenance activity, and social roles activity (χ = 8.8, P = 0.003; χ = 16.1, P = 0.000; χ = 7.4, P = 0.006), higher in the respective middle-score groups (χ = 5.5, P = 0.019; χ = 6.6, P = 0.010; χ = 2.7, P = 0.103), and highest in the respective low-score groups.
The intellectual activity scores were divided into a high-score group (scoring 4; n = 300), middle-score group (scoring 3; n = 196), and low-score group (scoring 0 to 2; n = 156).
The social roles activity scores were divided into a high-score group (scoring 4; n = 214), middle-score group (scoring 3; n = 205), and low-score group (scoring 0 to 2; n = 234).
The participants' total functional capacity scores were divided into a high-score group (scoring 12 or 13; n = 213), middle-score group (scoring 10 or 11; n = 219), and low-score group (scoring 1 to 9; n = 219).
In contrast, the all-cause mortality was highest in the social roles activity low-score group, lower in the middle-score group and lowest in the high-score group, whereas cancer mortality was highest in the high-score social roles activity group, lower in the middle-score group and lowest in the low-score group (Table 2).
All-cause mortality was most prevalent in the total functional capacity low-score group, more prevalent in the middle-score group, and least prevalent in the high-score group (Table 2).
The overall survival rate was highest in the instrumental self-maintenance activity high-score group (χ = 27.2, P = 0.000), lower in the middle-score group (χ = 7.2, P = 0.007), and lowest in the low-score group.
As shown in Table 2, in a pattern similar to that of the total functional capacity groups, both the all-cause mortality and the respiratory mortality were most prevalent in the instrumental self-maintenance activity low-score group and more prevalent in the middle-score group compared to those in the high-score group.
With the Kaplan Meier method followed by a log-rank test to assess the significance between survival curves, it was revealed that the overall survival rates during the 12-year follow-up period were significantly higher in the total functional capacity high-score group (χ = 11.5, P = 0.001) and middle-score group (χ = 7.4, P = 0.007) compared to the low-score group.
