We are living longer partially as a result of treating issues that would previously have gone untreated or poorly treated. Most things we treat with medication

We are living longer partially as a result of treating issues that would previously have gone untreated or poorly treated. Most things we treat with medication we treat because they have negative health outcomes otherwise like earlier deaths. Longer lifespan on medication = more percentage of life on medication, but of course people would typically rather have that than a shorter un-medicated life. I think there probably is a factor of quality of life dropping due to things like obesity raising in prevalence, but I think what I stated above could be the more likely/common explanation that doesn't require the "glass half empty" view. One other factor is we are able to treat more things each year than ever before. There are numerous diseases that have gone from death sentence to a mostly normal life with the help of medication. This would also influence the percentage statistic.