Association of handgrip strength asymmetry and weakness with cognitive function: a nationally representative cohort study

•Handgrip strength asymmetry with the non-dominant hand having a higher value than the dominant hand predicted accelerated cognitive decline.•Handgrip strength asymmetry with the dominant hand having a higher value than the non-dominant hand was beneficial for cognitive function.•Handgrip weakness predicted accelerated cognitive decline.•Handgrip strength asymmetry may be used to monitor cognitive impairment. To describe the association of handgrip strength asymmetry and weakness with cognitive function among Chinese middle-aged and older adults. We used data from four waves (2011, 2013, 2015, and 2018) of the China Health and Retirement Longitudinal Study. Handgrip strength was measured at baseline. Handgrip strength asymmetry was defined on the basis of the ratio of handgrip strength of the non-dominant hand to that of the dominant hand (i.e. non-dominant/dominant): a ratio of 1.1 as non-dominant handgrip strength asymmetry. Weakness was defined as a handgrip strength of