Objective: To investigate the association between weight or Body Mass Index (BMI) and the development of hand osteoarthritis (OA).
Methods: Systematic review of observational studies. Medical databases were searched up to April 2008. Articles which presented data on the association between weight and hand OA were selected. The qualities of these studies were then assessed by two independent reviewers using a 19 criteria scoring system. Using the mean scores of all studies as cut-off value, the studies were deemed as high- or low- quality. Study quality and study designs were combined to determine the level of evidence using best-evidence synthesis which consisted of five levels of evidence.
Results: From the 25 studies included, two had cohort, three case-control and 20 cross-sectional study designs. Fifteen studies were considered as high-quality studies. Of these high-quality studies, one cohort, two case-control and seven cross-sectional studies showed a positive association between weight or BMI and hand OA. Based on three high-quality studies with preferred study designs (one cohort and two case-control) with a positive association, the level of evidence of the association between overweight and developing hand OA is moderate. The approximate risk ratio of this association is 1.9.
Conclusion: Weight or BMI is associated with hand OA development. The level of evidence of published studies is moderate according to best-evidence synthesis. Further high-quality cohort or case-control studies are needed to elucidate the role of weight in hand OA.