RT Journal Article SR Electronic T1 Does mild cognitive impairment affect the occurrence of radiographic knee osteoarthritis? A 3-year follow-up in the ROAD study JF BMJ Open JO BMJ Open FD British Medical Journal Publishing Group SP e001520 DO 10.1136/bmjopen-2012-001520 VO 2 IS 6 A1 Yoshimura, Noriko A1 Muraki, Shigeyuki A1 Oka, Hiroyuki A1 Kawaguchi, Hiroshi A1 Nakamura, Kozo A1 Tanaka, Sakae A1 Akune, Toru YR 2012 UL http://bmjopen.bmj.com/content/2/6/e001520.abstract AB Objective To determine whether mild cognitive impairment (MCI) increases the risk of occurrence or progression of radiographic knee osteoarthritis (KOA) in a general population. Design Population-based cohort study. Setting Residents in mountain and seaside areas of Wakayama Prefecture, Japan. Participants 1690 participants (596 men, 1094 women; mean age 65.2 years old) were enrolled from the large-scale cohort for the Research on Osteoarthritis (OA)/osteoporosis Against Disability (ROAD) study initiated in 2005 to investigate epidemiological features of OA in Japan. Of these, 1384 individuals (81.9%; 466 men, 918 women) completed the second survey including knee radiography 3 years later. Primary outcome measures Radiographic KOA was defined as Kellgren-Lawrence (KL) grade ≥ 2 using paired x-ray films. Incidence of KOA during follow-up defined on radiographs as KL grade ≥2, progression of KOA defined as a higher KL grade (either knee) at follow-up compared with baseline. MCI defined as a summary mini-mental state examination (MMSE) score ≤23. Associations between MCI and incidence or progression of KOA were analysed. Results The annual cumulative incidence of KOA was 3.3%; for progression of OA it was 8.0%. On logistic regression analysis adjusted for age, gender, regional differences, body mass index, grip strength (worse side), smoking, alcohol consumption, regular exercise and history of knee injury, baseline MMSE summary score was significantly associated with the incidence of KOA (+1 MMSE score; OR 0.83, p=0.010). Baseline MCI was also significantly associated with the incidence of KOA (vs non-occurrence of KOA; OR 4.90, p=0.027). There was no significant association between MMSE scores, the presence of MCI and progression of KOA (+1 MMSE score; OR 0.96, p=0.232; vs non-progression of KOA; OR 1.38, p=0.416). Conclusions MCI significantly increases the risk of incident radiographic KOA, but not the progression of KOA.