Abstract
Aim:
This study aimed to investigate the prevalence of type 2 diabetes (T2D) among Danish nursing home residents (aged ⩾65 years).
Methods:
Individuals with T2D in the Danish population of older adults in 2018 were identified using a Danish diabetes register based on administrative and clinical register data. Data on age, sex, type of housing, educational level and place of origin were obtained from various high-quality administrative registers. We calculated frequencies of T2D among older adults living in nursing homes and in other types of housing. We performed a multiple logistic regression analysis to estimate the odds ratio (OR) of T2D among people living in nursing homes and adjusted for sex, age, educational level and place of origin.
Results:
All Danish older adults aged ⩾65 years, alive and living in Denmark on 31 December 2018 were included (N=1,170,517). Nursing home residents accounted for 37,891 older adults, and of these, 19% had T2D, whereas 14% of older adults living in other types of housing had T2D. According to the multiple logistic regression analysis, nursing home residents had a higher OR of having T2D compared to older adults living in other types of housing (OR=1.47; confidence interval 1.43–1.51) when adjusting for socio-demographic factors.
Conclusions:
The prevalence of T2D in nursing home residents exceeds the prevalence in the background population at ⩾65 years of age. This indicates a need for increased focus on individualised interdisciplinary care plans aimed at maintaining physical function and maximising quality of life for this group of vulnerable older adults.
Keywords
Introduction
The prevalence of type 2 diabetes mellitus (T2D) is increasing in many countries around the world [1,2], including Denmark [3], and is predicted to increase further [4,5]. The same pattern is seen in older adults [6].
T2D in older adults is associated with several co-morbidities, higher mortality, lower functional level and greater health service use [7,8]. Furthermore, the risk of hypoglycaemia increases with increasing age [9], adding to the complexity of managing T2D in this age group. Although T2D is generally associated with deterioration in quality of life (QoL) and mainly affects health-related QoL [10,11], older age seems to have an additional negative impact on QoL in people with T2D [12].
In order to accommodate the needs of older adults with T2D in a timely manner in order to maintain the best possible QoL for as long as possible, it is essential that health-care providers are aware of this group of vulnerable older adults.
Approximately 3% of the Danish population ≥65 years of age live in nursing homes, and data from the USA report a high prevalence of diabetes in long-term care facilities [13]. To our knowledge, the prevalence of T2D in Danish nursing home residents has not yet been investigated. The Danish personal identification number makes it possible to combine information from a wide range of administrative registers, and the register coverage is in general high [14]. Danish registers thus present unique possibilities to perform studies on health, diseases and living circumstances. The main aim of the present study was to describe the prevalence of T2D among Danish nursing home residents (aged ⩾65 years).
Methods
Data
The study was based on Danish register data from 2018. Data on age, sex and place of origin were obtained from the Danish Civil Registration System. Place of origin is determined by parents’ place of birth. Origin is considered Danish if at least one parent is born in Denmark and has Danish citizenship. Individuals living in nursing homes were identified via municipal reporting to the eldercare database, whereas data on the highest level of completed education were obtained from the Danish Education Register. Highest level of education was divided in to three education groups. Primary and lower secondary school includes people who have no formal education beyond compulsory schooling in Denmark. Upper secondary school, short and vocational education covers non-mandatory schooling and education above compulsory schooling and below higher education. Higher education includes people with three years or more of higher education.
People with T2D were identified via the Danish diabetes register created by Carstensen et al. [3], which uses data from various administrative registers to identify people with T1D and T2D who receive diabetes treatment and care in various health-care settings [3].
The study was approved by Region Zealand on behalf of the Danish Data Protection Agency (REG-118-2019).
Statistical analysis
We calculated the frequency of TD2 in deciles ≥65 years of age living in nursing homes or other types of housing. The frequencies of T2D were further broken down by socio-demographic factors, including sex (male, female), age group (65–74 years, 75–84 years, 85-94 years, ⩾95 years), place of origin (Denmark, other Western country, non-Western country) and educational level (primary and lower secondary school, upper secondary school, short and vocational education, higher education). We calculated crude odds ratios (ORs) of having T2D related to type of housing and co-variables (sex, age, place of origin and educational level). Further, we calculated ORs of having T2D when living in nursing homes compared to other types of housing using multiple logistic regression. The multiple logistic regression model was adjusted for sex, age, place of origin and educational level.
A small part (22,241 cases; 1.9%) of the total population of older people (⩾65 years of age) living in Denmark had missing information on educational level. A sub-analysis of this group revealed that individuals in the group were older and more often of non-Western origin than the rest of the population (data not shown). Thus, in the logistic regression analysis, missing values were imputed as primary and lower secondary school completed, since people in Denmark of higher age or non-Western origin more often are not educated beyond this educational level [15,16]. All statistical analyses were performed in SAS v9.4 (SAS Institute, Cary, NC).
Results
The total population consisted of 1,170,517 people aged ⩾65 years living in Denmark in 2018. Of these, 37,891 older adults lived in nursing homes. Of these nursing home residents, 19% (7232 people) had T2D identified by the Danish diabetes register, whereas 14% of the older adults living in other types of housing had T2D according to the register (Table I). Generally, higher percentages of T2D were seen in men, in people aged 75–84 years, in people of non-Western origin and in people with primary and lower secondary school as their highest level of completed education (Table I). Type of housing as well as socio-demographic factors (age, sex, place of origin and education) all influenced odds of T2D both in crude and multiple analysis (Table II). The multiple logistic regression analysis found that overall nursing home residents had 47% higher odds of having T2D compared to people living in other types of housing (OR=1.47; confidence interval 1.43–1.51) when adjusting for socio-demographic factors.
Danish population aged ⩾65 years, alive and living in Denmark on 31 December 2018.
Broken down by socio-demographic variables (sex, age, place of origin and educational level), nursing home status and T2D status. Horizontal percent for people living in nursing homes and other types of housing, respectively. T2D: type 2 diabetes.
Place of origin is determined by parents’ place of birth. Origin is considered Danish if at least one parent is born in Denmark and has Danish citizenship.
Primary and lower secondary school: ⩽10 years of school– equivalent to compulsory schooling in Denmark. Upper secondary school, short and vocational education: non-mandatory schooling and education above compulsory schooling and below higher education. Higher education: three or more years of higher education.
Logistic regression analysis of odds of having T2D when living in a nursing home compared to other types of housing.
Odds ratios for co-variates (place of origin, educational level, age and sex) are shown. Odds ratio, confidence limits and p-values are shown for both crude and multiple analysis. N=1,170,517 individuals.
Missing values of educational level were imputed as the lowest educational level (primary and lower secondary school).
Discussion
Almost one in five (19%) of nursing home residents (aged ⩾65 years) had T2D compared to one in seven (14%) of older adults living in other types of housing in Denmark in 2018. Other studies describing the prevalence of T2D among older adults found that the T2D prevalence in Europe in 2019 was 20.1% in the general older population aged 65–99 years [6], while the general prevalence in Denmark in 2017 ranged from about 8% to 19% in the different ages from 65 to 99 years among men and women [3].
To our knowledge, the discrepancy in prevalence of T2D between older adults living in nursing homes compared to older adults in other types of housing in Denmark has not been described elsewhere. Further, the present data showed that nursing home residents had 47% higher odds of having T2D compared to older adults in other types of housing. The reason for this is unclear. However, one hypothesis could be that living in a nursing home promotes a sedentary lifestyle [17] and enhances access to an energy-enriched diet [18] in order to prevent general weight loss and malnutrition [19] – both factors that could increase the risk of developing T2D after moving into a nursing home. Another hypothesis is that late complications and co-morbidities of T2D as well as decrease in functional level and frailty associated with T2D [2,7,20] may be contributory causes of admission to a nursing home. Accordingly, results showed that in the age groups 65–74 and 75–84 years, prevalence of T2D was markedly higher among nursing home residents compared to older adults in other types of housing, although the difference in prevalence of T2D between the groups diminished in age groups >84 years. In particular, the oldest age group (⩾95 years) did not differ in prevalence of T2D between nursing homes and other types of housing and had the lowest prevalence of all age groups. It is likely that this finding could be due to an increased all-cause mortality in people with T2D [21], which could explain a lower proportion with T2D in the oldest age group.
However, the cross-sectional design of the present study cannot confirm either of these hypotheses, which preferably should be investigated in a longitudinal cohort design of older individuals included before admission to nursing home.
Looking at both older adults in nursing homes and other types of living, a higher prevalence of T2D was seen in people of non-Western origin and in people with primary and lower secondary school as their highest level of completed education. These results are supported by other studies describing the association between higher risk of T2D and low educational level [22,23], as well as non-Western origin [24].
Independently of the causes of the high prevalence of T2D in nursing home residents, demographic changes towards an aging population make it increasingly important to focus on and possibly prevent complications leading to the need for nursing home admission and to ensure that the extra years of life are worth living, despite chronic illnesses such as T2D. Thus, QoL and health-promoting initiatives for older people living in nursing homes will become ever more important in the years to come [25]. Geriatric syndromes, diabetes complications and hypoglycaemia are associated with lower health related QoL to a comparable degree in older adults with diabetes [26]. It is therefore suggested that in order to maximise QoL in this group of older adults, screening for and avoiding hypoglycaemia should be considered a high priority in order to prevent complications [26]. In addition, several studies describe the coexistence of diabetes and sarcopenia, frailty and disabilities [27–30]. Even though mechanisms of the path from diabetes to disability are not fully understood [27], the importance of multimodal interventions, including nutrition, exercise and glycaemic control, is emphasised in order to delay or prevent the progression of frailty to disability in this vulnerable group of older adults [27,29]. Thus, a recent expert consensus statement by Strain et al. [30] recommends that assessment of frailty [31,32] should be a routine component of diabetes reviews for all older adults [30].
Tailored care plans should simplify treatment regimens and focus on individualised glycaemic control, sufficient nutrition and protein intake, as well as personalised exercise dependent on the current level of functional abilities [12]. Furthermore, increased focus on the education of nursing home staff to improve diabetes management of nursing home residents with T2D should be considered [33]. Timely individualised approaches to managing T2D in nursing home residents may help them maintain physical function and ultimately improve their QoL.
This register study of prevalence of T2D in nursing homes is based on high-quality administrative registers in Denmark [14]. General practitioners in Denmark do not report patient diagnosis to administrative registers, which complicates the identification of people with T2D. However, the diabetes register improves sensitivity by including information from several sources: the National Patient Register, National Health Service Register, Medicine Products Register, Danish Adult Diabetes Database and eye screening records in the Diabase [3]. Yet, it is likely that there is some level of underdiagnosing of T2D that could not be identified by register data.
Conclusions
One in five older adults living in nursing homes in Denmark live with T2D, and nursing home residents have 47% higher odds of having T2D compared to older adults in other types of housing. Due to the high prevalence of T2D in nursing home residents, action is required to ensure tailored interdisciplinary care plans aimed at maintaining physical function and maximising QoL for this group of vulnerable older adults.
Footnotes
Acknowledgements
The authors would like to acknowledge the Steno Diabetes Center Copenhagen for sharing valuable guidance on the identification of people with diabetes based on the Danish diabetes register. We thank Margit Dall Aaslyng, Tenna Christoffersen, Hannah Holt Bentz and Line Lindahl-Jacobsen for contributing to important discussions of the results. Moreover, we are grateful to the Steno Diabetes Center Zealand for supporting the present study with a research grant.
Declaration of conflicting interests
The authors declared no potential conflicts of interest with respect to the research, authorship and publication of this article.
Funding
The authors disclosed receipt of the following financial support for the research, authorship and/or publication of this article: The study was funded by the Steno Diabetes Center Zealand.
