Study of anemia in long-term care (SALT): prevalence of anemia and its relationship with the risk of falls in nursing home residents

ABSTRACT

Objective: The objectives of the current study were twofold. First, this study examined the prevalence of anemia in nursing home residents in the USA and its relationship with key resident characteristics and medical conditions. Second, the study explored whether an association between anemia and falls is evident in this same population.

Research design and methods: Chart review was conducted in 40 nursing homes across the USA. Residents were randomly sampled and considered eligible if they: were ≥18 years of age; had ≥1 hemoglobin (Hb) level reported during the data uptake period of 1/1/04–2/1/05 (first occurrence defined as index Hb); had a recorded serum creatinine level; maintained residency in the facility; and did not receive dialysis during the 6-month post-index follow-up period. Resident demographics, laboratory values, comorbid conditions, medication regimens, falling events, physical functioning measures, and hospitalizations were obtained from chart data. The relationship between selected resident characteristics and comorbidities was explored with index Hb level, using multiple linear regression. Logistic regression was used to analyze the relationship between falling and recurrent falls with anemia (index Hb <13 g/dL and <12 g/dL in men and women ≥15 years, respectively) adjusting for selected variables presumed to be related to falls.

Limitations: Study limitations include the retrospective design and limited follow-up, potential for biased selection of relevant covariates, gaps in time between index Hb levels and falling events, non-random selection of nursing homes, limits to quality and detail in data extracted from residents’ medical charts, and confounding of anemia therapy with index hemoglobin level.

Results: A total of 564 sampled residents met the criteria for data completeness and were retained for analysis; of these, 70% were female. Mean age was 81 ± 12.3 years (±SD). Mean index Hb level was 11.9 ± 1.8 g/dL (12.2 ± 2.0 for males, 11.7 ± 1.6 for females). Of all residents studied, 56% were identified as anemic (64% males, 53% females) from index Hb level. In all, 53% of anemic residents were receiving an identified therapy, with 72% of these treated residents receiving iron. None received an erythropoietic-stimulating agent (ESA). For index Hb level, the regression coefficient was significant for female (p = 0.002), African-American race (p = 0.012), glomerular filtration rate (GFR) <60 mL/min/1.73 m² (p < 0.001), diabetes (p = 0.004), cancer (p < 0.001), asthma (p = 0.002), GI bleeding (p = 0.012), and inflammatory disease (p = 0.039). Except for asthma, these factors were associated with a decrease in Hb. In the regression model for the dependent variable of falling, anemia (OR = 2.26, p < 0.001), psychoactive medication use (OR = 2.18, p = 0.001), and age 85+ years (OR = 2.08, p = 0.016) were associated with more than twice the risk of falling.

Conclusions: Anemia in nursing home residents appears to be under-recognized. For residents over 70 years, the prevalence of anemia in both male and female residents was approximately four times the rate reported in a study of older community dwellers (Salive et al., 1992). Both anemia and the use of psychoactive medications are potentially modifiable factors strongly associated with falling. Since falls and related fractures are events associated with high morbidity and mortality, each of these factors deserves special consideration for potentially reducing the risk of such events in the nursing home.

Key words: :

• Anemia
• Falls
• Hemoglobin
• Long-term care
• Nursing home

Acknowledgment

Declaration of interest: The analysis was sponsored by Centocor Ortho Biotech Services, LLC. Research data used in this study were collected by Synnovate Healthcare. At the time this research was conducted NP had received honoraria as a speaker from, and was a consultant to, Centocor Ortho Biotech Services, LLC (a Johnson & Johnson company). BB and SM were employees and shareholders of Johnson & Johnson, and GR and PFO were consultants to Centocor Ortho Biotech Services, LLC. No editorial assistance was provided during the preparation of this manuscript. Earlier analyses of these study data were presented at the American Medical Directors Association Annual Symposium in Hollywood, FL, USA, 3/29/07–4/1/07 (prevalence findings) and at the International Society for Pharmacoeconomics and Outcomes Research Annual International Meeting in Arlington VA, USA, 5/19/07–5/23/07 (falls findings). Details are: (prevalence findings) Pandya N, Bookhart B, Mody S, et al. Study of anemia in long-term care (SALT) – prevalence of anemia in nursing home residents: relationship with resident characteristics and comorbidities; (falls findings) Pandya N, Bookhart B, Mody S, et al. Study of anemia in long-term care (SALT): relationship between anemia and falls in the nursing home setting.