Prevalence, Comorbidity and Investigation of Anemia in the Primary Care Office

Anemia has a myriad of causes and its prevalence is growing. Anemia is associated with increased all-cause hospitalization and mortality in community-dwelling individuals above age 65 years. Our aim was to determine the prevalence and severity of anemia in adult patients in our primary care office and to determine the relationship between anemia and medical comorbidities.

Electronic medical records of 499 adult patients in our suburban internal medicine office were reviewed who had had at least one hemoglobin value and did not undergo moderate to high-risk surgery in the preceding 30 days.

About one-fifth (21.1%) of the patients had anemia. The mean age of patients with anemia was 62.6 years. Among all patients with anemia, 20.3% were males and 79.6% were females. Of these patients, 60.1% had mild anemia (hemoglobin 11 - 12.9 g/dL) and 39.8% had moderate anemia (hemoglobin 8 - 10.9 g/dL). For every year of increase in age, there was 1.8% increased odds of having anemia. African-American race had 5.2 times greater odds of having anemia than the Caucasian race. Hispanic race had 3.2 times greater odds of having anemia compared to the Caucasian race. Patients with anemia had a greater average number of comorbidities compared to patients without anemia (1.74 and 0.96, respectively; P < 0.05). There was a statistically greater percentage of patients with essential hypertension, hypothyroidism, chronic kidney disease, malignancy, rheumatologic disease, congestive heart failure, and coronary artery disease in the anemic population as compared to the non-anemic population. Of the patients, 41% with mild anemia and 62% with moderate anemia underwent additional diagnostic studies. Of the patients, 14.8% had resolution of anemia without therapy in 1 year, 15.7% were on iron replacement therapy, and 6.5% were on cobalamin therapy. No specific etiology of anemia was found in 24% of patients.

A higher prevalence of anemia was associated with advancing age, African-American and Hispanic ethnicity, and comorbidities, such as essential hypertension, hypothyroidism, chronic kidney disease, malignancy, rheumatologic disease, congestive heart failure, and coronary artery disease. It is important to be aware of the demographic factors and their relationship to anemia in primary care.