Self- and interviewer-reported cognitive problems in relation to cognitive decline and dementia: results from two prospective studies

Table 2 Combined association of SCP and ICP with cognitive decline among Chinese (N = 10,976) and European (N = 40,499) middle-aged and older participants

	Non-SCP & Non-ICP	SCP & Non-ICP	Non-SCP & ICP	SCP & ICP
China Health and Retirement Longitudinal Study (CHARLS)^a
N	7064	2772	628	512
Age-adjusted model	0 (ref.)	−0.003 (−0.015, 0.010)	−0.008 (−0.034, 0.018)	−0.061 (−0.092, −0.031) *
Multivariate model 1 (MV1)	0 (ref.)	−0.003 (−0.015, 0.009)	−0.008 (−0.033, 0.017)	−0.052 (−0.082, −0.023) *
Multivariate model 2 (MV2)	0 (ref.)	−0.003 (−0.015, 0.009)	−0.008 (−0.033, 0.017)	−0.051 (−0.080, −0.021) *
Survey of Health, Ageing and Retirement in Europe (SHARE)^b
N	29,177	9657	1021	644
Age-adjusted model	0 (ref.)	−0.001 (−0.005, 0.004)	0.002 (−0.013, 0.016)	−0.028 (−0.048, −0.008) *
Multivariate model 1 (MV1)	0 (ref.)	−0.0003 (−0.005, 0.005)	0.003 (−0.011, 0.017)	−0.024 (−0.044, −0.004) *
Multivariate model 2 (MV2)	0 (ref.)	0.0002 (−0.005, 0.005)	0.004 (−0.011, 0.018)	−0.024 (−0.043, −0.004) *
Pooled results^c
Multivariate model 2 (MV2)	0 (ref.)	−0.0003 (−0.005, 0.004)	0.001 (−0.011, 0.013)	−0.035 (−0.061, −0.009) *

Abbreviations: SCP Self-reported cognitive problems, ICP Interviewer-reported cognitive problems
Age-adjusted model: adjusted for age, age², and follow-up year
Multivariate model 1 (MV1): CHARLS: further adjusted for gender, residence, marital status, education level, household income, smoking status, drinking status, sleep duration, BMI, depressive symptoms, ADL, and physical activity level; SHARE: further adjusted for gender, residence, marital status, education level, household income, smoking status, drinking status, BMI, depressive symptoms, ADL, vigorous physical activity, moderate physical activity, and country
Multivariate model 2 (MV2): further adjusted for baseline cognitive function score
Estimates of the mean differences in cognitive decline across groups were β coefficients of cross-product terms of exposure and follow-up year
^aDuring an average of 5.4 years of follow-up, the rate of cognitive decline was −0.039 (−0.044, −0.034) z-score/year for Chinese
^bDuring an average of 5.7 years of follow-up, the rate of cognitive decline was −0.027 (−0.029, −0.025) z-score/year for Europeans
^cResults from the multivariate model 2 (MV2) were pooled using the random-effects model
^*P <0.05

ISSN: 1741-7015