Anaesthesia use accelerates cognitive decline in older adults

Regional (RA) and general (GA) anaesthesia for surgeries result in comparable rates of global cognition decline, a recent study has found. However, RA does not seem to affect memory.

The study included 1,819 older adults (mean age, 78.9±5.1 years; 52 percent male) in whom cognitive function was longitudinally evaluated using combinations of self-reports, apolipoprotein E genotyping and different batteries. Researchers identified all procedures with RA or GA by accessing the Rochester Epidemiology Project’s medical record linkage system.

Most participants were GA-naïve (n=1,171), while 537 received a total of 915 GA administrations. On the other hand, 111 patients were exposed to 137 RA shots. Majority (86 percent) were cognitively normal at enrolment, while 14 percent (n=255) had mild cognitive impairment.

Exposure to any type of anaesthesia accelerated the decline of global cognitive function as opposed to the GA-naïve participants (RA: slope difference, –0.041, 95 percent CI, –0.071 to –0.01; p=0.011; GA: slope difference, –0.061, –0.078 to –0.044; p<0.001). The difference between the two types of anaesthesia was not significant (slope difference, –0.02, –0.053 to 0.014; p=0.25).

Analysis according to cognitive domains showed that the effect of RA (slope difference, –0.036, –0.071 to –0.001; p=0.045) was explained mostly by the faster rate of decline in attention/executive function relative to naïve counterparts. GA also exerted a significant effect on this domain (slope difference, –0.052, –0.072 to –0.033; p<0.001).

Notably, GA also resulted in a significantly greater acceleration of decline in the memory domain as opposed to controls (slope difference, –0.065, –0.084 to –0.045; p<0.001). RA had no such effect. The rates of decline after GA and RA exposure only differed for the domain of memory (difference, –0.053, –0.094 to –0.012; p=0.011), and not for any of the other domains.