Our study characterised health resource and medicine use by Australian centenarians and near centanarians. We found that, while use is frequent with 98% accessing GP services and using prescription medicines, for most health services studied the proportion of centenarians and near centenarians who accessed them was similar to or less than the proportion of veterans aged 65 to 74 who accessed them. Amongst centenarians and near centenarians who accessed one or more health service, in most cases they did so a similar number of times in comparison to younger people.
The need to know more about the health status of Australian centenarians to inform health and public policy development has been highlighted . Recent studies provide evidence to support the notion that longevity is not necessarily associated with excessive health resource use and costs. An American study found that although overall health expenditure increased with age, this was largely due to increased use of nursing homes by the elderly . They found that within the elderly population, the rate of acute health care use and expenditure decreased with increasing age . An Australian study found similar results. Using Medicare claims data, they found that high health service usage and costs were associated with death, but not increasing age . This finding has also been reflected in British[24, 25] and New Zealand studies. Our findings provide further evidence that suggests, in comparison to younger elderly people, Australians centenarians and near centenarians are not excessive users of health services.
Our study highlighted that the health service most commonly accessed by centenarians and near centenarians was GP visits; accessed by 98% of near centenarians and centenarians during the study period. This was slightly higher than the rate of GP visits by centenarians in other countries; with a study of Greek centenarians finding that 79% had visited their GP in the previous year , and a Danish study finding that 42% of centenarians had visited their GP in the previous three months . Use of other health services by centenarians and near centenarians has not been extensively reported previously. A study of Danish centenarians showed the mean number of hospitalisations per person per three years at the ages 97 to 99 was 1.45, equivalent to 0.48 hospitalisations per person per year; while a study of centenarians in the USA found a mean of 0.6 hospital admissions per centenarian per year . Our study reported results slightly differently and showed that, amongst those hospitalised, the mean number of admissions during the year was 1.5 and 1.8 amongst centenarians and near centenarians respectively. Expression of our results in a comparable way to the prior research provides an overall mean of 0.29 hospitalisations per centenarian per year and 0.43 hospitalisations per near centenarian per year; comparable to the rate of hospitalisation amongst Danish near centenarians and lower than the rate of hospitalisation amongst American centenarians.
Use of medicines is the most common health activity undertaken by Australians, and our results show that centenarians and near centenarians use multiple medicines at similar levels to their younger elderly counterparts. However, the types of medicine used differ greatly. For example, 3% of centenarians received lipid lowering medicines compared to 49% of those aged 65 to 74. Calcium channel blockers and beta blockers were dispensed to 15% and 11% of centenarians, compared to 24% and 23% of those aged 65 to 74. This may reflect lower prevalence of chronic conditions in centenarians for which these medicines are used to treat, or conversely, it may reflect under-treatment of chronic conditions in centenarians. There is evidence of lower prevalence of hypertension amongst centenarians,[6, 28] and studies of Italian and Japanese centenarians have demonstrated low total cholesterol in this age group . Prevalence of diabetes amongst centenarians is also low in some studies [6, 8]. However, other studies have suggested that there is under treatment of chronic conditions in the very old, [23, 29–32] in some cases due to under diagnosis . Diagnoses are not included in the DVA dataset, so we were unable to determine whether our results indicate differing prevalence of chronic diseases by age group or under-treatment in centenarians.
Centenarians and near centenarians are rarely included in randomised controlled trials, meaning that data regarding the safety and efficacy of medicines in centenarians and near centenarians is limited. One study found that out of more than 50,000 randomised controlled trials published between 1990 and 2002, only 84 focussed on people aged 80 years and over, and the mean age of patients included in these studies was 83 years . Safety of drug therapy in centenarians and near centenarians is of particular concern due to the increased risk of adverse drug reactions associated with increasing age . Efficacy of drug therapy in centenarians and near centenarians is also an important consideration. It has been suggested that GPs may be less willing to prescribe medicines for the very old in the absence of efficacy data , particularly given the increased risk of adverse effects in this population. Results of our study have highlighted that nearly all centenarians and near centenarians use medicines so it is important that future research focuses on the safety and efficacy of medicines in this age group.
Our study is limited by lack of information on the actual health conditions and comorbidities suffered by centenarians and near centenarians. It is possible that low use of some health resources in our study reflects the inability to access required services. It has been suggested that lower rates of hospitalisation amongst very old people may not reflect better health, but rather the preference of families and doctors to care for the very old in the home [26, 38]. We were unable to determine whether this influenced results of our study.
Although we reported the mean number of unique medicines dispensed to centenarians and near centenarians, and the proportion dispensed each class of medicine; we did not describe persistence with drug therapy or differences in doses used by centenarians and near centenarians in comparison to other elderly people. This limitation has also been evident in prior studies of centenarians, which have described the proportion of centenarians using medicine by drug class, but not dosage or duration of therapy [3, 9, 10]. This is an important consideration and should be the focus of future research, because safe doses of medicine may be lower and appropriate duration of therapy may differ between centenarians, near centenarians and younger patients.
Although our cohort was limited to veterans, results are likely to be applicable to other elderly Australians. Age specific comparisons of DVA gold card holders with the wider Australian population have shown that DVA gold card holders with no service related disability have a similar number of GP visits (rate ratio 0.99, p > 0.5) and slightly fewer hospitalisations (rate ratio 0.97, p < 0.05) per year compared to other elderly Australians . The likelihood of receiving a prescription at a GP visit is similar for the DVA population and the wider Australian population . Our results are likely to be applicable to other Australian centenarians and near centenarians.