Most elderly readers find it easier to read text with more spacing between words, letters and lines. Avoid bizarre or deocrative fonts that may confuse the reader. Avoid typefaces that are light and small. I nstead use medium and bold type weights that are easier to read. Along with larger type sizes and a font that provides adequates spacing between letters and words, use paragraph indents.
Indents help elderly readers navigate from one line to another.
Keep in mind also that working memory declines with age. Text designed for elderly eyes may also prove easier to read for traditional readers. Department of Educational Technology, San Diego State.