The overall aim of this thesis is to investigate whether drug treatment is unequally distributed among older adults on the basis of age and socioeconomic position.
All studies in this thesis are based on nationwide register data from the Swedish Prescribed Drug Register (SPDR) record-linked to other registers in Sweden.
In Study I, we investigated differences in drug use between centenarians (≥100 years; n=1,672), nonagenarians (90-99 years; n=76,584) and octogenarians (80-89 years; n=383,878). The results showed that the proportion of people living in institutions increased with age, but the number of drugs was similar across the age groups. Centenarians were more likely to use psychotropics (hypnotics/sedatives, antidepressants and anxiolytics) and pain killers (minor analgesics and opioids). This might indicate that drug treatment has a more palliative character in centenarians than in the other age groups. Centenarians used older types of cardiovascular drugs which could reflect a lack of regular re-evaluation of drug use in centenarians or a disinclination to make changes in well-functioning drug therapy among the extremely old.
The aim of Study II was to investigate educational differences (as a measure of socioeconomic position) in osteoporosis drug use before and after osteoporosis-related fractures among persons aged 75-89 years (n=645,429). There is a general underuse of osteoporosis drugs among older adults in Sweden. Our results suggest that older persons with lower levels of education are less likely to receive drug treatment both before and after an osteoporosis-related fracture (only statistically significant in women) than their more highly educated counterparts. The educational differences were more pronounced for newer and more potent osteoporosis drug treatments. Lower socioeconomic position seems to be linked to a lower use of osteoporosis drugs – a drug therapy that is generally underused.
In Study III, the aim was to investigate educational differences in antipsychotic drug use among older adults (aged 75-89 years) with and without dementia (n=641,566). Antipsychotic drugs are commonly used to treat behavioral and psychological symptoms of dementia, but the use of these drugs has been associated with increased morbidity and mortality. Efforts have therefore been made to reduce the prescribing of antipsychotic drugs to older adults with dementia. We found a higher use of antipsychotic drugs among persons with lower levels of education, both among persons with and without dementia. Lower socioeconomic position seems to be positively associated with a higher use of antipsychotic drugs – a drug therapy that is generally overused.
We investigated educational differences in being prescribed psychotropic drugs by specialist physicians among older (aged 75-89 years) psychotropic drug users (n=221,579) in Study IV. Higher levels of education were associated with more access to geriatrician and psychiatrist prescribing. However, when place of residence was taken into account, the association between higher education and psychotropic prescription by geriatricians became non-significant, whereas the association between higher education and prescription by psychiatrists persisted. Limited access to specialists could be one mechanism liking lower socioeconomic position to less optimal drug treatment.
This thesis contributes to a better understanding of how socioeconomic position and age are related to drug use. In general, lower socioeconomic position and older age seem to be associated with less optimal drug treatment. However, the mechanisms behind these findings are probably complex and need to be addressed in further research to provide a foundation for social policy.