Article continues below advertisementTom Dumont, the guitarist of the iconic band No Doubt, announced his diagnosis of early-onset Parkinson's disease through an emotional Instagram post. The 58-year-old musician described this personal update as an important moment, stating that he was diagnosed "a number of years ago."Article continues below advertisementSource: tomdumontphoto/InstagramTom Dumont, guitarist of No Doubt, publicly revealed that he was diagnosed with early-onset Parkinson's disease several years ago.