Prevalence of anemia in Chinese nursing home older adults: implication of age and renal impairment

Aim: There is little data regarding the prevalence and associated comorbidities of anemia in Chinese nursing home older adults. The objective of this study was to investigate the prevalence and associated comorbidities of anemia in Chinese nursing home older adults.

Methods: We carried out a retrospective cross-sectional study in nine nursing homes in Hong Kong. The hemoglobin (Hb) level, mean corpuscular volume (MCV), serum creatinine and comorbidities data of residents were examined. Older adults were regarded as anemic according to the World Health Organization criteria (Hb <13 g/dL for men and <12 g/dL for women). The glomerular filtration rate (eGFR) was estimated by the Modification of Diet in Renal Disease Study (MDRD [Chinese-adjusted]) equation. Patients with chronic renal impairment were defined as having eGFR <60 mL/min/1.73 m(2) .

Results: A total of 812 residents were included (mean age 86.0 ± 7.6 years). The mean hemoglobin was 12.0 ± 1.8 g/dL in men and 11.4 ± 1.6g/dL in women. The mean eGFR was 75.1 ± 31.7 mL/min/1.73 m(2) . A total of 67.0% of residents had anemia (70.5% in men and 65.2% in women). Anemic older adults were older and had a higher prevalence of renal impairment than non-anemic older adults (P<0.001). There was no significant difference between the two groups regarding the prevalence of other comorbidities. When stratified into different age groups, there were significant correlations between anemia and renal impairment in all subgroups (age ≤ 80 years, P<0.05; age 81-90 years, P<0.01; age >90 years, P<0.05). The same correlation was found between normocytic anemia and renal impairment. Conversely, when stratified according to eGFR (≥ 60 mL/min/1.73 m(2) vs <60 mL/min/1.73 m(2) ), we did not observe a significant correlation between anemia and age group.

Conclusion: In conclusion, anemia is prevalent in Chinese nursing home residents and is strongly associated with renal impairment. Further studies of early identification and management of anemia with renal impairment are recommended in this population.