To our knowledge, this is the first study to evaluate the level of ADL and IADL among different age groups as well as the potential factors associated with functional disability in a nationally representative sample of Chinese older inpatients. Application of a mixed-effect generalized linear model not only controlled the cluster effect of hospital wards but also examined the effect of potential associated factors, including indicators for sociodemographic characteristics, physical health variables, and mental health variables, on both the prevalence and extent of functional disability.
Our results suggested that with increasing age, the main activities that affected ADL as graded from high to low were walking up and down stairs, mobility, bathing, transfers (from bed to chair and back), and toilet use. However, in Spain, changes in the ADL were reported to occur mainly in dressing, toilet use, transfers, mobility, and stair climbing (9). These differences can be attributed to the physical limitations of wearing bandages around legs or arms in older Spanish patients who underwent dermatologic surgery. The activities most impactful on IADL in the present study as graded from high to low were shopping, food preparation, mode of transportation, and laundry. This finding is consistent with those of previous studies reporting that IADL rapidly declines with increasing age in terms of speed and executive function (18) with regard to, for example, household tasks, traveling, and shopping (19). Therefore, developing targeted nursing plans to help older inpatients to self-manage their daily activities is fundamental to the management of individuals’ aging progress.
The levels of ADL and IADL decreased gradually with the increase in participants’ age in this study, differing from certain studies conducted in welfare institutions and among ethnic minorities (Demura et al., 2001; Ran et al., 2017). These differences can be ascribed to the participants of these two studies not being representative of the general older population. However, the findings of our study were consistent with reports from the Netherlands and the Republic of Ireland that aimed to analyze factors associated with ADL and IADL disability among general community-dwelling older adults (6, 19). The differences in ADL and IADL that appear to exist between the general aging population and older adults from welfare institutions or ethnic minorities require further study. In addition, although aging cannot be controlled, our results suggest that older adults are at risk of a decline in functional independence. Therefore, evidence-based nursing intervention programs aimed at improving ADL and IADL independence among older adults are warranted.
Apart from age, emaciation, frailty, and depression bring about a series of negative effects on functional ability. It has been proved that BMI is effective in evaluating functional status in the aging population, with emaciation being related to poor physical function (20, 21). Meanwhile, older adults with frailty were more likely to experience disability in ADL and IADL (22, 23). Previous studies also reported that functional disability was associated with depressive moods in older adults (24–27). Therefore, to ameliorate functional disability in older inpatients, it might become essential for nurses to formulate dietary strategies and implement physiological interventions or psychotherapy for older inpatients with emaciation, frailty, or depression (26, 28, 29).
The results of our study showed that transferring patients from the emergency department or from other hospitals could increase the risk of ADL disability. First, the geriatric population in emergency departments are considered high-risk because they are susceptible to reduced immobility, impaired cognition, failure to eat and drink, incontinence, and functional decline (30). Consequently, they are at high risk of ADL disability (31, 32). A second explanation is that older patients who are transferred from district hospitals or community hospitals, which provide only basic inpatient services (33), may not receive systematic medical treatment and nursing care, thus leading to a higher incidence of poor ADL.
Previous studies provided strong evidence that former smoking is a risk factor for functional disability (34, 35). Our study indicated that former smokers had a higher risk of IADL disability, which further supported previous research findings. However, higher-level education and residing in a building without elevators were likely to maintain a better IADL performance, perhaps because well-educated participants could better comprehend the development of disease and maintain their physical function with a positive attitude (36). In addition, residence in apartment block-type buildings in China is associated with better economic conditions. There exists the possibility that the geriatric population living in such buildings have a better quality of life and health monitoring that help maintain IADL function.
Interestingly, current alcohol drinkers had a low risk of IADL disability. A previous study indicated that older adults who consumed small to moderate amounts of alcohol were more likely to maintain mobility than nondrinkers, which might be related to the fact that moderate alcohol consumption has been associated with a decreased risk of cardiovascular events (34). However, the detailed evaluation of alcohol consumption based on information about quantity and frequency of drinking alcoholic beverages requires further research.
In the present study, falling accidents in the previous 12 months, hearing dysfunction, cognitive dysfunction, urinary dysfunction, and defecation dysfunction were significantly associated with functional disability, which further supports previous research findings (11, 34, 37, 38). These dysfunctions of physical and mental health had a marked effect on functional ability of older inpatients and restrained them from taking part in social interaction, which made them more likely to experience a poorer quality of life. Therefore, regarding these factors, more advanced risk factor assessment scales and nursing care measures may be useful in managing functional disability among older patients in the future (39).