Dovepress Cognitive impairment associated with slower physical test results Table 2 Comparisons of the covariates education, health indicators, and comorbidity between cases, intermediates, and controls (n = 2115) Education Elementary school not completed Elementary school completed Secondary school completed $1 year extra study or university with/without degree Smoking habits Current smoker Stopped smoking Never smoked Drinking habits No alcohol/drank alcohol a few times during the past year but not during the past month Drank alcohol during the past month Physical activity during the past year Hardly any, mostly sedentary Light activity (2–4 hours/week) Strenuous activity (1–2 hours several times per week) Comorbidity Pulmonary disease (asthma, chronic bronchitis, emphysema) Coronary heart disease (myocardial infarction, angina) Diabetes Rheumatoid arthritis Neurological disease Osteoarthritis of knee/hip Fractures of lower extremities Congestive heart failure with symptoms Anemia BMI Normal weight, BMI # 24.99 Overweight, BMI 25.0–29.99 Obese, BMI $ 30.0 Pain Back Right leg Left leg Medication Use of sedatives Cases n = 328 6 (1.9) 190 (58.6) 80 (24.7) 48 (14.8) 44 (13.6) 121 (37.3) 159 (49.1) 126 (39.1) 196 (60.9) 67 (20.7) 168 (52.0) 88 (27.2) 44 (13.5) 58 (17.7) 25 (7.6) 22 (6.8) 1 (0.3) 76 (23.2) 32 (9.8) 34 (10.7) 32 (9.8) 112 (34.5) 144 (44.3) 69 (21.2) 101 (30.8) 103 (31.4) 107 (32.6) 47 (14.3) Intermediates n = 457 20 (4.4) 246 (54.5) 119 (26.4) 66 (14.6) 82 (18.2) 165 (36.7) 203 (45.1) 165 (36.9) 282 (63.1) 89 (19.8) 217 (48.2) 144 (32.0) 57 (12.5) 89 (19.5) 28 (6.1) 19 (4.2) 9 (2.0) 88 (19.3) 46 (10.1) 39 (8.8) 35 (7.7) 158 (34.8) 197 (43.4) 99 (21.8) 121 (26.5) 150 (32.8) 135 (29.5) 59 (12.9) Controls n = 1330 27 (2.0) 586 (44.4) 401 (30.4) 307 (23.2) 245 (18.5) 532 (40.2) 546 (41.3) 358 (27.2) 960 (72.8) 184 (13.9) 652 (49.4) 483 (36.6) 142 (10.7) 171 (12.9) 82 (6.2) 62 (4.7) 22 (1.7) 215 (16.2) 100 (7.5) 51 (3.9) 63 (4.7) 473 (35.6) 598 (45.1) 256 (19.3) 374 (28.1) 429 (32.3) 394 (29.6) 184 (13.8) P ,0.001 – – – – ns – – – ,0.001 – – 0.001 – – – ns 0.001 ns ns ns 0.009 ns ,0.001 0.001 ns – – – ns ns ns ns Note: The values given are numbers of subjects, with percentages in parentheses. Abbreviations: P, probability; BMI, body mass index; ns, not significant. cognitive impairment, categorized into the three groups, as the independent variable. A contrast test was performed to assess the difference between intermediates and controls. Each model was adjusted for the same confounders men- tioned above. All calculations were performed using SPSS software Windows (v 18.0 IBM Corporation, Armonk, NY). The level of significance was set to less than 0.05. Ethics The study was approved by the Regional Ethical Review Board, Lund University (LU 744-00). All participants gave written consent. Clinical Interventions in Aging 2012:7 Results The age (P , 0.001) and sex (P = 0 .008) distributions dif- fered significantly among the three groups. Cases were older than both of the other groups, and the proportion of women was higher in the control group (Table 1). A higher propor- tion of individuals in the control and intermediate groups were married/cohabiting than in the case group. There were more widows/widowers in the case group than in the two other groups. Regarding walking ability, more dependence on walking aids was found among the cases than in the other two groups. No differences were found among the groups regarding place of residence and ADL (Table 1). Total independence in P-ADL was noted in 73.9% of the cases, submit your manuscript | www.dovepress.com Dovepress 199