18 People read faster with a longer line length, but they perfer a shorter line length

Longer line lengths are easier to read because they interfere less with the flow of saccades and fixations

Use a longer line length (100 characters per line) if reading speed is an issue. Use a shorter line length (45-72 characters per line) f reading speed is less critical. 

For a multipage article consider using multiple columns and a shorter line length (45 characters per line).