Table 4.

Contribution of potential influential factors in the association of physical multimorbidity with subjective concentration and memory complaints.

	Total effect		Direct effect		Indirect effect
	OR [95% CI]	P-value	OR [95% CI]	P-value	OR [95% CI]	P-value	%Mediateda
Subjective concentration complaints
Obesity	2.58 [2.25, 2.96]	<0.001	2.57 [2.24, 2.95]	<0.001	1.00 [0.99, 1.02]	0.708	NA
Smoking	2.58 [2.26, 2.95]	<0.001	2.56 [2.24, 2.93]	<0.001	1.01 [1.00, 1.02]	0.047	0.8
Alcohol dependence	2.60 [2.27, 2.97]	<0.001	2.57 [2.25, 2.94]	<0.001	1.01 [1.00, 1.02]	0.130	NA
Number of stressful life events	2.60 [2.26, 2.98]	<0.001	2.10 [1.83, 2.41]	<0.001	1.23 [1.19, 1.29]	<0.001	22.1
Perceived stress	2.67 [2.32, 3.06]	<0.001	2.45 [2.13, 2.81]	<0.001	1.09 [1.06, 1.12]	<0.001	8.8
Depression	2.67 [2.32, 3.07]	<0.001	2.44 [2.13, 2.81]	<0.001	1.09 [1.06, 1.12]	<0.001	8.9
Any anxiety disorder	2.64 [2.30, 3.03]	<0.001	2.29 [1.99, 2.62]	<0.001	1.16 [1.12, 1.20]	<0.001	14.9
Sleep problems	2.74 [2.39, 3.15]	<0.001	2.18 [1.90, 2.50]	<0.001	1.26 [1.21, 1.31]	<0.001	22.8
Total	2.88 [2.47, 3.36]	<0.001	1.74 [1.50, 2.03]	<0.001	1.65 [1.54, 1.78]	<0.001	47.5
Subjective memory complaints
Obesity	2.39 [2.13, 2.69]	<0.001	2.37 [2.11, 2.67]	<0.001	1.01 [0.99, 1.02]	0.302	NA
Smoking	2.34 [2.09, 2.63]	<0.001	2.31 [2.06, 2.60]	<0.001	1.01 [1.00, 1.02]	0.010	1.5
Alcohol dependence	2.35 [2.09, 2.64]	<0.001	2.33 [2.07, 2.62]	<0.001	1.01 [1.00, 1.02]	0.133	NA
Number of stressful life events	2.37 [2.11, 2.67]	<0.001	1.99 [1.77, 2.25]	<0.001	1.19 [1.15, 1.23]	<0.001	20.1
Perceived stress	2.38 [2.11, 2.68]	<0.001	2.23 [1.98, 2.51]	<0.001	1.07 [1.05, 1.09]	<0.001	7.6
Depression	2.41 [2.14, 2.71]	<0.001	2.23 [1.98, 2.51]	<0.001	1.08 [1.05, 1.11]	<0.001	8.7
Any anxiety disorder	2.41 [2.14, 2.71]	<0.001	2.12 [1.88, 2.39]	<0.001	1.13 [1.10, 1.17]	<0.001	14.4
Sleep problems	2.44 [2.16, 2.76]	<0.001	2.03 [1.80, 2.29]	<0.001	1.20 [1.16, 1.25]	<0.001	20.6
Total	2.65 [2.33, 3.02]	<0.002	1.74 [1.53, 1.98]	<0.001	1.53 [1.43, 1.63]	<0.001	43.3

Abbreviations: OR Odds ratio; CI Confidence interval.

Physical multimorbidity was defined as ≥2 physical conditions.

Subjective concentration complaints were assessed with the following question: “In the past month, have you had any problems with concentrating on what you were doing?”. Subjective memory complaints were assessed with the following question: “Have you noticed any problems with forgetting things in the past month?”.

Model was adjusted for sex, age, ethnicity, qualification and income.

^aMediated percentage was only calculated when the indirect effect was significant (P < 0.05).