Hand osteoarthritis and aging: the results of a large-scale cross-sectional study

Abstract

<i>Background</i>: Because osteoarthritis (OA) is associated with morbidity and mortality, we hypothesized that radiographic hand OA would generally be associated with chronic systemic morbidity and it will be less prevalent in longevity populations than in non-longevity populations. <i>Aims</i>: 1) to evaluate the association between chronic systemic morbidity and radiographic hand OA; 2) to compare the prevalence and the mode of the development of radiographic hand OA in three longevity populations (Abkhazian, Azerbaijani and Georgian) vs. two non-longevity populations (Russian and Chuvashians). <i>Methods</i>: Radiographic hand OA was evaluated using the left hand radiograms in 14 joints according to the Kellgren and Lawrence’s (K-L) grading system. Each individual was characterized by the total number of affected (K-L≥2) joints (NAJ). The prevalence of hand OA was defined as the presence of at least one affected joint. Morbidity data were attained from their medical records and divided into 9 categories by a research physician. The longevity index was calculated as a ratio of the number of individuals aged >90 years versus the number of people aged >60, expressed in per mills (‰). The population with the longevity index >40‰ was considered as the longevity population. Statistical analyses included the prevalence estimation and ANOVA. <i>Results</i>: Radiographic hand OA was statistically significantly and positively associated with the ischemic heart disease. A significant difference in the age standardized prevalence of hand OA was found between each pair of the studied samples, except between the Chuvashians, Russians and Georgians and between the Azerbaijanis and Abkhazians. The lowest prevalence was found in the Abkhazians followed by the Azerbaijanis and Georgians. The highest prevalence was found in the Chuvashians. ANOVA showed significant differences between the age-adjusted means of NAJs. The lowest age-adjusted NAJ was found in the Abkhazian population followed by the Azerbaijanis and Georgians. The highest NAJ was found in the Chuvashians. <i>Conclusions</i>: The results of our study showed association between ischemic heart diseases and hand OA. Longevity populations showed lower hand OA prevalence and NAJ compared to a non-longevity population, that can be interpreted as that longevity populations age slower. Additional follow-up studies are needed to verify this hypothesis.