May 6 (Reuters) - German dialysis specialist Fresenius Medical Care reported better-than-expected first-quarter net income on Thursday thanks to lower patient deaths as 51% of its patients had received at least one dosis of COVID-19 vaccination.

First-quarter net income of the world's largest provider of dialysis treatments fell 6% to 249 million euros ($298.82 million) on a currency-adjusted basis, better than analysts' average forecast for a currency-adjusted net income of 237 million euros in a company-provided poll.

The company confirmed its outlook for 2021 and said it expected the adverse impact of patient mortality on organic growth to reach the highest point in the second quarter and then begin to drop. ($1 = 0.8333 euros) (Reporting by Antonis Pothitos in Gdansk Editing by Tomasz Janowski)