Metformin and incident osteoarthritis : Causal insights from a co-twin control study
Aims: In a co-twin control design, we aimed to examine whether individuals who initiate metformin treatment have an altered risk of incident diagnosis of osteoarthritis (OA), for up to 11 years after starting the treatment, compared with their non-treated co-twin. Methods: In all twin pairs different for metformin treatment (N=1 261 pairs) and all eligible twins/singletons (N=52 341) aged 35–75 ye
