title: Hand osteoarthritis in longevity populations.
abstract: OBJECTIVE
  Previous studies have reported that centenarians escape the major agerelated diseases. No studies on prevalence and severity of osteoarthritis (OA) in longevity population have previously been reported. Because OA is associated with morbidity and mortality, we hypothesized that radiographic hand OA would generally be less prevalent and would develop at a later age in longevity populations vs non-longevity populations. Aim was to evaluate the prevalence and mode of development of radiographic hand OA in three longevity populations (Abkhazians, Azerbaijanis and Georgians) and in one non-longevity population (Russians).
  
  
  METHODS
  Crosssectional observational study. Longevity index was calculated as a ratio of the number of individuals aged >90 years vs the number of people aged >60, expressed per mil (‰). A population with longevity index >40‰was considered as a longevity population. Radiographic hand OA was evaluated using the left hand radiograms in 14 joints according to Kellgren and Lawrence's (K-L) grading system. Each individual was characterized by the total number of affected (K-L≥2) joints (NAJ). Prevalence of hand OA was defined as the presence of at least one affected joint. Statistical analyses included prevalence estimation, linear, logistic and polynomial regressions, and ANOVA.
  
  
  RESULTS
  A significant difference (p<0.003) in age standardized prevalence of hand OA was found between each pair of studied samples, except between Russians and Georgians and between Azerbaijanis and Abkhazians (p>0.05). The lowest age-standardized prevalence was found in Abkhazians, followed by Azerbaijanis and Georgians. The highest prevalence was found in Russians. ANOVA showed significant differences (p<0.01) between the age-adjusted means of NAJs. The lowest age-adjusted NAJ was found in the Abkhazian population, followed by Azerbaijanis and Georgians. The highest NAJ was found in Russians.
  
  
  CONCLUSIONS
  We observed that the pattern of radiographic hand OA in longevity populations differs from the pattern in non-longevity populations. On average, first joints with OA appear at an older age, and progression of hand OA, measured by NAJ, is slower.
authors.affiliation: Department of Physical Therapy, Recanati School for Community Health Professions, Faculty of Health Sciences, Ben-Gurion University of the Negev, P.O.B. 653 Beer Sheva 84105, Israel. kleonid@bgu.ac.il.
authors.forename: Leonid
authors.initials: L
authors.lastname: Kalichman
authors.forename: Michael
authors.initials: M
authors.lastname: Korostishevsky
authors.forename: Valery
authors.initials: V
authors.lastname: Batsevich
authors.forename: Eugene
authors.initials: E
authors.lastname: Kobyliansky
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D001382:Azerbaijan / Q000453:epidemiology; D003430:Cross-Sectional Studies; D005846:Georgia (Republic) / Q000453:epidemiology; D050276:Hand Bones / Q000000981:diagnostic imaging*; D006801:Humans; D008136:Longevity; D008297:Male; D010003:Osteoarthritis / Q000000981:diagnostic imaging* / Q000453:epidemiology* / Q000208:ethnology; D011153:Population; D015995:Prevalence; D011859:Radiography; D012426:Russia / Q000453:epidemiology