Table 4 Results of multiple logistic regression analyses for ADL/IADL disability

Gender (Reference category: Male)

Female

0.685** (0.416;0.867)

1.278* (1.032;1.549)

1.378* (1.039;1.746)

0.537** (0.481;0.623)

1.108 (0.821;1.454)

1.215 (0.867;1.568)

Age in years (Reference category: 65–69)

70–74

1.335* (1.098;1.622)

1.343* (1.172;1.538)

1.486* (1.245;1.642)

1.281* (1.104;1.485)

1.426* (1.283;1.683)

2.087** (1.753;2.331)

75 or older

1.882*** (1.556;2.275)

2.924*** (2.584;3.308)

3.677*** (3.223;4.069)

2.619*** (2.332;2.937)

2.925*** (2.586;3.386)

4.381*** (3.861;4.927)

Living arrangement (Reference category: With relatives)

Living alone

1.623** (1.356;1.943)

1.352* (1.203;1.524)

1.528** (1.395;1.674)

1.012 (0.903;1.129)

1.072 (0.989;1.161)

1.182 (0.904;1.266)

Educational status (Reference category: College or higher)

Elementary school or lower

1.883*** (1.243;2.853)

1.013 (0.749;1.374)

1.099 (0.883;1.367)

1.698*** (1.411;2.044)

1.026 (0.878;1.199)

1.017 (0.894;1.157)

Middle school

1.548** (1.103;2.087)

1.696*** (1.264;2.275)

1.085 (0.871;1.353)

1.324* (1.078;1.627)

1.106 (0.931;1.313)

1.214 (0.949;1.406)

High school

1.202* (1.071;1.493)

1.295* (1.086;1.502)

1.133 (0.929;1.382)

1.101 (0.906;1.337)

1.144 (0.969;1.353)

1.088 (0.947;1.251)

Health parameters

Body mass index (Reference category: Normal)

Underweight

1.652** (1.102;2.615)

1.075 (0.822;1.407)

1.032 (0.838;1.271)

1.975*** (1.442;2.705)

1.451* (1.224;1.716)

1.058 (0.904;1.238)

Overweight

1.331* (1.113;1.589)

1.321* (1.167;1.495)

1.427* (1.294;1.574)

1.067 (0.963;1.181)

1.342* (1.238;1.455)

1.379* (1.287;1.477)

Obese

1.814** (1.492;2.209)

1.292* (1.133;1.469)

1.024 (0.927;1.133)

1.011 (0.902;1.134)

1.071 (0.983;1.166)

1.075 (0.903;1.256)

Self-rated health (Reference category: Good)

Bad

2.654*** (2.225;3.166)

2.437*** (2.164;2.744)

1.834*** (1.671;2.013)

1.903*** (1.713;2.115)

1.904*** (1.759;2.062)

1.892*** (1.764;2.025)

Difficulty in daily activities related to body pain (Reference category: No)

Yes

1.405* (1.127;1.816)

1.228* (1.088;1.385)

1.064 (0.968;1.171)

1.312* (1.106;1.626)

1.051 (0.968;1.142)

1.008 (0.941;1.082)

Physical activity (Reference category: Yes)

No

2.169*** (1.692;3.381)

1.628** (1.399;2.171)

1.471* (1.182;1.869)

1.757** (1.251;2.275)

1.336* (1.152;1.528)

1.159* (1.095;1.326)

Depression status (Reference category: No)

Yes

2.295*** (1.713;3.084)

2.132*** (1.443;2.861)

2.081*** (1.339;2.744)

1.659** (1.381;1.993)

1.317** (1.155;1.501)

1.323** (1.176;1.482)

Cognitive function (Reference category: Normal)

Cognitive decline

1.687** (1.396;2.043)

1.441* (1.118;1.484)

1.362* (1.238;1.498)

1.301* (1.165;1.452)

1.454* (1.342;1.575)

1.397* (1.306;1.495)

Dementia

3.211*** (2.583;3.992)

1.914*** (1.652;2.217)

2.561*** (2.277;2.882)

2.492*** (2.169;2.863)

2.088*** (1.873;2.328)

1.834*** (1.664;2.022)

Number of chronic diseases (Reference category: 0)

1

1.593** (1.269;1.999)

1.952** (1.694;2.253)

1.423* (1.281;1.581)

1.165* (1.039;1.307)

1.147* (1.053;1.249)

1.068 (0.996;1.146)

2

2.366*** (1.864;3.004)

1.369* (1.161;1.615)

1.337* (1.185;1.507)

1.503** (1.321;1.709)

1.122* (1.017;1.233)

1.263* (1.162;1.374)

≥ 3

2.491*** (1.912;3.254)

1.862** (1.555;2.231)

1.619** (1.411;1.858)

1.895*** (1.195;2.527)

1.611** (1.441;1.803)

1.462* (1.159;1.675)

Functional disability at baseline

ADL disability at baseline (Reference category: No)

Yes

4.155*** (3.331;5.182)

2.271*** (1.857;2.775)

2.134*** (1.767;2.578)

2.061*** (1.379;2.882)

1.668** (1.369;2.107)

1.261* (1.082;1.476)

IADL disability at baseline (Reference category: No)

Yes

4.709*** (3.976;5.577)

3.118*** (2.751;3.534)

2.291*** (2.057;2.551)

13.675*** (12.410;15.071)

7.094*** (6.474;7.772)

3.091*** (2.829;3.376)