J Mazurek, M Zack, B Mattson, R Duffy
activities of daily living, arthritis, disabled persons, nursing homes, ohio
J Mazurek, M Zack, B Mattson, R Duffy. Arthritis And Physical Functioning Among Nursing Home Residents - Ohio, 1999. The Internet Journal of Geriatrics and Gerontology. 2005 Volume 3 Number 1.
To evaluate association between arthritis and activity of daily living (ADL) disability among nursing home residents, we examined 1999 Ohio nursing home assessment data. Multivariate logistic regression analysis was performed to obtain adjusted odds ratios. A total of 152,882 (93%) were aged 21 years or older, had information on their arthritis status, sex, race, and were included in the study; 31% were assessed as having arthritis. Residents had the greatest difficulty with bathing, transferring, dressing, personal hygiene, and toilet use and the least difficulty with eating. Among and within each ADL, those with arthritis typically had more disability and need for assistance in performing ADLs than those without arthritis. The association between arthritis and ADL disability varied by ADL and subgroups defined by demographic characteristics, body mass index, and the presence of comorbid conditions. Clinicians might prevent or decrease disability levels through intervention regarding arthritis among these subgroups.
This study has been supported by the Ohio Department of Health.
Arthritis, which encompasses >150 diseases and conditions, is among the most common of all chronic diseases (1, 2). In 2001, the estimated prevalence of doctor-diagnosed arthritis among U.S. adults was 21 percent (42.7 million persons) and among Ohio adults, 30 percent (2.5 million persons) (2, 3). Arthritis prevalence increases with age, affecting approximately 48 percent of the U.S. population aged ≥65 years (2). It occurs more often among women than men and among non-Hispanic whites and non-Hispanic blacks than among those of other racial/ethnic groups (1, 2).
Presence of a chronic condition, including arthritis, is associated with a decrease in physical, cognitive, or sensory functioning (4,5,6). Of 44 million adults with disabilities, 7.2 million (17.5 percent) reported arthritis and rheumatism as the primary cause of their disability (6). Arthritis might also increase risk for other diseases including cardiovascular disease, hypertension, and chronic pulmonary disease (7). Persons with arthritis experience a higher burden of illness than persons without arthritis, a burden that appears to be increasing over time (7,8,9). Moreover, other conditions among persons with arthritis (e.g., heart disease, pulmonary disease, obesity, cancer or hip fracture) sometimes increase risk for disability (9, 10,11,12,13). With increasing age and number of chronic conditions, disability rises rapidly (4, 13). Finally, patients with disability and comorbidity incur substantially higher medical costs (14, 15).
Relatively few studies have focused on the relation between disability and arthritis. The majority of studies examined the type and levels of disability experienced by persons with chronic diseases or impairments, including arthritis, focusing on the impact of comorbidity measured as a presence of comorbid condition, a count of comorbid conditions, a comorbid index, or as a specific combination of diseases (11,12,13, 16,17,18). To better understand consequences of the co-occurrence of specific disease combinations in one person, we followed a recent recommendation to evaluate the effects of multiple impairments on disability (19). This cross-sectional study analyzed existing 1999 data from 1,013 Ohio nursing homes to determine the association between arthritis (the period prevalence) and the physical functioning of nursing home residents.
We included all persons admitted for at least 1 day in 1999 to a certified Ohio nursing home who had undergone a comprehensive assessment during that admission, had been aged ≥21 years, and for whom sex and race had been identified. Residents with arthritis were defined as those who had arthritis coded on all assessments during 1999. Residents without arthritis were those who never had arthritis coded on any of their assessments. A resident with inconsistent coding for arthritis (i.e., its presence on one assessment and its absence on another) was excluded from the study.
Each nursing home resident in Ohio undergoes a mandatory, comprehensive assessment of her or his health status for planning care by using the federal Centers for Medicare and Medicaid Services' Minimum Data Set (MDS) (20). A comprehensive assessment is required within 14 days of admission, quarterly, annually, and whenever a resident's health status has changed substantially. The assessment must be conducted or coordinated, if an interdisciplinary team completes it, by a registered nurse. Nursing homes transmit the information from the assessment electronically to the state health department where it is compiled in a database. The Centers for Medicare and Medicaid Services and the Ohio Department of Health provided the data to the study investigators.
Information on the presence of arthritis was obtained from the MDS Resident Assessment Instrument's Section I: Disease diagnoses, items 1a–u. This data requires a physician-documented diagnosis in the clinical record and includes degenerative joint disease, osteoarthritis, and rheumatoid arthritis. Other forms of arthritis (e.g., Sjogren syndrome, gout), not included in this analysis, are recorded on another part of the assessment (Section I, items 3a–e) with related International Classification of Diseases (9th revision) codes.
To determine association between arthritis and activity of daily living (ADL) disability among nursing home residents, we conducted a cross-sectional study (21). We compared residents with respect to the following specific demographic features and diseases (comorbid conditions) on the basis of their comprehensive assessments: race (white versus other races); sex (male versus female); age group (20–39, 40–49, 50–59, 60–69 [reference group], 70–79, 80–89, 90–99, 100–119 years); body mass index (BMI; underweight [< 18.5 kg/m2], normal weight [range: 18.5–24.9 kg/m2; reference group], and overweight/obese [ ≥ 25.0 kg/m2]) (22); education level; diabetes; arteriosclerotic heart disease (ASHD); cardiac dysrhythmias; congestive heart failure (CHF); hypertension; hip fracture; osteoporosis; pathological bone fracture; stroke; vision disease (presence of cataract, diabetic retinopathy, glaucoma, or macular degeneration); other circulatory disease (presence of deep vein thrombosis, peripheral vascular disease, or other cardiovascular disease); and paresis or plegia (presence of hemiparesis, hemiplegia, paraplegia, or quadriplegia). Because MDS collects weight in pounds and height in inches we converted weight into kilograms and height into meters and calculated BMI as weight in kilograms divided by the square of the height in meters. Variables were selected on the basis of the availability of information in MDS.
The main outcome measure was the presence of disability for each of 11 specific ADLs: bed mobility, transferring from bed to chair, walking within the room and in the corridor, locomotion within and away from the nursing home unit, dressing, eating, using the toilet, personal hygiene, and bathing (20, 21). These ADLs were scored from information on resident self-performance or need for assistance in the MDS Resident Assessment Instrument's Section G: Physical Functioning and Structural Problems, items 1a–j, and 2. The specific scores for performing each ADL were the following (20): 0 = independent; 1 = supervision, 2 = limited assistance, 3 = extensive assistance, and 4 = total dependence. To assess the association between arthritis and the physical functioning of nursing home residents, we contrasted the ADL scores of residents with arthritis with those of residents without arthritis. If an ADL score was either 0 or 1, we considered the resident as performing the ADL independently (i.e., the disability was absent); otherwise, we considered the resident as performing the ADL dependently (i.e., the disability was present). If the resident did not perform the specific ADL before a comprehensive assessment (required within 14 days of admission, every 3 months, annually, and whenever a resident's health status changes substantially ) or if no score was assigned (a missing score), this observation was excluded from the analysis.
To determine whether the presence of arthritis among nursing home residents affects their ability to perform different ADLs, our analyses proceeded in stages. First, we examined the prevalence of arthritis and other diseases among nursing home residents and grouped related comorbid diseases. Second, we calculated crude odds ratios and their corresponding 95 percent confidence intervals for the prevalence of ADL disability among residents with arthritis. Third, to evaluate whether nursing home residents with arthritis differ from nursing home residents without arthritis with respect to potential confounders that might affect their ability to perform ADLs, we calculated crude odds ratios and their corresponding 95 percent confidence intervals of arthritis associated with demographic characteristics or comorbid conditions. Fourth, we evaluated whether demographic characteristics or comorbid conditions modified the association between the disability and arthritis (accepting only those interactions statistically significant at the level,
Of 164,989 Ohio nursing home residents assessed by using MDS in 1999, a total of 152,882 (93 percent) were aged ≥ 21 years, had a known sex and race, and had information on their arthritis status. Of those residents, 31 percent (47,926) were assessed as having arthritis (table 1). The median age of all residents was 81 years (range: 21–114 years); 104,057 (68 percent) were female. The majority of residents (89 percent; 135,919) were white, and 68 percent (103,995) had a high school education or less. For nine of the 11 ADLs, residents with arthritis demonstrated significantly more disability (12 percent to 46 percent) than residents without arthritis. Those with arthritis demonstrated no difference in personal hygiene and 17 percent less disability in eating than those without arthritis.
After adjustment for the potentially confounding effects of sex, race, age group, BMI, and comorbid conditions, the association between arthritis and disability for all ADLs except bathing differed among subgroups defined by demographic characteristics, BMI, and comorbid conditions (table 2). The following results highlight, for the different ADLs, only the specific subgroups where the association of arthritis with adjusted risk of ADL disability varied; in all other subgroups, arthritis had a limited effect on this risk.
Arthritis was associated with only 6 percent increased risk for bed immobility among normal-weight residents, but 17 percent among underweight residents and 19 percent among overweight/obese residents.
Arthritis was associated with increased risk for difficulty transferring only among those without hip fracture and without other circulatory diseases but did not affect this risk among those with either condition. Among white residents, arthritis increased this risk approximately 20 percent, but among those of other races, approximately 52 percent.
Walking within the room was more difficult among those with arthritis than those without arthritis but only if these residents were aged 60–69 years, either of normal weight or overweight/obese, and had no CHF, no stroke, and no vision diseases. Among these groups, arthritis was associated with 38 percent increased risk for difficulty walking within the room among normal weight residents and 65 percent among overweight/obese residents. Among other subgroups, walking within the room was no more difficult among those with arthritis than those without arthritis.
Walking in the corridor was more difficult among those with arthritis than those without arthritis but only among those aged 20–69 years without vision disease. Compared with those without arthritis, residents aged 20–59 years with arthritis had more difficulty (62 percent) walking in the corridor than those aged 60–69 years with arthritis (28 percent). Among other subgroups, walking in the corridor was no more difficult for those with arthritis than those without arthritis.
White residents aged 60–69 years with arthritis but without diabetes mellitus, ASHD, and stroke had 46 percent more difficulty with locomotion on the nursing home unit than their counterparts without arthritis. Older whites with arthritis and without these conditions had only 16 percent more difficulty with such locomotion than their counterparts without arthritis. However, older residents of other races with arthritis resembled the younger whites because they too had 47 percent more difficulty with locomotion within the nursing home unit than their counterparts without arthritis.
Those with arthritis but without diabetes and ASHD had 17 percent more difficulty with locomotion away from the nursing home unit than their counterparts without arthritis. Arthritis did not affect this kind of locomotion among other subgroups. Among those without osteoporosis, residents with arthritis had more difficulty with dressing than those without arthritis; arthritic residents of other races had more difficulty (35 percent) than white residents (15 percent). Residents of other races with arthritis had 24 percent more difficulty using the toilet than residents of other races without arthritis, but arthritis did not make using the toilet more difficult among whites. Among those without osteoporosis, vision disease, and peripheral circulatory disease, normal-weight and obese residents with arthritis usually had less difficulty eating than their counterparts without arthritis. Younger (aged 20–29 years), normal-weight residents with arthritis had approximately 45 percent less difficulty eating than comparably aged normal-weight residents without arthritis.
Younger, overweight/obese residents with arthritis had approximately 58 percent less difficulty eating than comparably aged overweight/obese residents without arthritis. Older, overweight/obese residents with arthritis had 29 percent less difficulty eating than older, overweight/obese residents without arthritis.
Among those without CHF and peripheral circulatory disease, normal weight and overweight/obese residents with arthritis had approximately 16 percent less difficulty with personal hygiene than their counterparts without arthritis. However, underweight residents with arthritis had approximately the same difficulty with personal hygiene as underweight residents without arthritis. The 12 percent increase in difficulty with bathing among those with arthritis compared with those without arthritis was consistent across all subgroups.
In this study, we examined the association of arthritis with different ADL disabilities among Ohio nursing home residents. Although this was a cross-sectional study and the temporal relation between cause and effect could not be determined, we believe that arthritis and the comorbid conditions typically preceded rather than followed the ADL disabilities; thus, the results represent the true effect of arthritis on ADL disability.
We determined that 31 percent of residents were assessed as having arthritis and that arthritis has different effects on the risk for disability for specific ADLs. Residents had the greatest difficulty with bathing, transferring, dressing, personal hygiene, and toilet use but the least difficulty with eating. Among and within each ADL, those with arthritis typically had more disability and need for assistance in performing ADLs than those without arthritis. The degree of this increased disability varied among different subgroups as defined by ADL, demographics, and clinical characteristics.
Similar to other reports, Ohio nursing home residents demonstrate increases in the prevalence of comorbid conditions and in the prevalence of disability of ADLs with increasing age, with the greatest increases each decade among those aged ≥ 60 years (24,25,26,27,28,29). Arthritis-disabled residents have more ADL disabilities than residents without arthritis. Overall, such residents have more ADL disabilities (range: 38.7 percent to 93.2 percent) than community-dwelling adults (27, 28). The high prevalence of disability might be expected because residents of nursing homes experience a higher burden of diseases, which places them at higher risk for institutionalization (30).
Our data confirm previous findings that the functional status is not the simple result of a single disease (18). Arthritis has different effects on the risk for disability for specific ADLs that depend on subgroups as defined by demographic characteristics, BMI, and presence of specific comorbid conditions, including diabetes, ASHD, cardiac dysrhythmias, CHF, hypertension, hip fracture, osteoporosis, pathological bone fracture, stroke, vision disease, other circulatory disease, paresis or plegia (8, 10,11,12,13, 16, 18, 24). The different risks for disability among residents are not surprising given the fact that diseases and constellation of diseases are related to different types of disability, over and above the independent contributions of each disease to disability (4, 12, 13, 18). When arthritis and other conditions co-occur, they might not always have a synergistic effect on disability. However, the presence of both arthritis and one or more comorbid conditions often worsens certain disabilities. This observed differential effect of arthritis identifies subgroups with a group of other diseases that pose a special threat and where intervention regarding the arthritis might prevent or decrease levels of ADL disability beyond its independent effect (12, 13, 16, 28, 31, 32).
The MDS database collects information for all residents in certified nursing homes in Ohio. The information was obtained for all Ohio nursing home residents and was reported by the nursing staff provider who might know the resident well. To our knowledge, this was the first time that MDS data have been used to assess impact of arthritis on disability of different ADLs. The sample size was substantial, enabling the study of interactions among multiple subgroups. We identified the quantitative effect of the combinations of conditions that pose an increased risk for disability and the population in which comorbidity has an elevated impact on disability. Finally, studying 11 different types of disability is more informative than studying only one or any disability.
This study has limitations. It is a cross-sectional study, not a prospective study; therefore we were unable to prove the relation between cause and effect (33). However, arthritis and the comorbid conditions might precede rather than follow the ADL disabilities. The substantial prevalence of ADL disabilities among this population precluded the use of binomial regression to estimate relative risks because of numerical instabilities, and it forced the use of logistic regression, which might have exaggerated the associations between arthritis, comorbidities, and ADL disabilities. Moreover, we neither evaluated the severity of arthritis or other diseases nor accounted for the duration of nursing home stay. Because in the MDS database the kind of arthritis is not specified, our definition of arthritis is broad. Therefore, the overall effects we observed might differ with disease severity, remission status, and specific kind of arthritis. Finally, we did not validate the information (e.g., through record review) provided by the nursing homes. However, other researchers have reported that certain data elements recorded in MDS and its different components are valid (34,35,36) and that MDS data might be useful for cross-sectional study of patients likely to have functional impairments (37).
The results of this exploratory analysis provide evidence of need for additional research and can be used for epidemiologic research hypothesis generating. For example, there is a need to in-depth evaluation of biological plausibility and clinical relevance of the observed associations. If hypothesis testing, particularly in prospective studies, confirms our findings, this might suggest specific disability prevention interventions and treatment options.
Although exploratory in its nature, this report increases our knowledge of the ways in which comorbid diseases affect different types of disability. The results emphasize the importance of considering ADL, demographics, arthritis status, and presence of comorbid conditions when planning interventions among nursing home residents. Among nursing home residents, arthritis both increases the overall risk for disability, and certain subgroups with arthritis have an even higher risk for disability. Intervention among them might prevent or decrease levels of ADL disability and diminish medical costs of arthritis. These results indicate groups to be considered when developing a comprehensive approach to treating arthritis and related conditions, developing comprehensive disease management programs, and improving coordination of care (7, 38,39,40).
We are grateful to Dr Jennifer M. Hootman, Centers for Disease Control and Prevention for her thoughtful comments.
The findings and conclusions in this report are those of the authors and do not necessarily represent the views of the funding agency.
Jacek Mazurek CDC, NIOSH, DRDS, Surveillance Branch 1095 Willowdale Rd., MS HG 900.2 Morgantown, WV 26505 Phone: (304) 285-5983 Fax: (304) 285-6111 E-mail: ACQ8@cdc.gov