There is a potential association in the elderly between hypoxemia, bone mineral density, osteoporosis, and hemoglobin (Hb) levels. In fact, several studies have reported a concurrence of osteoporosis and anemia in certain conditions, including sickle cell anemia, chronic inflammatory conditions, and renal failure. However, little is known about the association between Hb levels and osteoporosis in general older populations.

The study by Laudisio et al assessed the association of Hb levels with ultrasound-derived T score, Z score, and stiffness index in all 358 subjects age 75 or older living in Tuscania, Italy January 2004. The authors also identified Hb cutoff levels that could potentially be used to identify participants with osteoporosis. Of the 387 participants living in the small Italian town, 23 subjects were excluded for missing data and 6 participants were excluded for treatment with biphosphonates. Questionnaires were used to assess socioeconomic status, lifestyle habits, physical activity, nutritional parameters, and other variables. Anemia was defined according to the World Health Organization criteria: Hb level <12 g/dL in women and Hb level <13 g/dL in men.

Anemia was detected in 43/358 (12%) of participants and osteoporosis was found in 153/358 (43%) of participants. In the final regression models, Hb levels were still associated with the ultrasound-derived T score (β=0.13; 95% CI=0.01–0.25; p=0.030), Z score (β=0.11; 95% CI=0.01–0.22; p=0.045) and stiffness index (β=1.87; 95% CI=0.51–3.21; p=0.007) after simultaneously adjusting for all potential confounders. The authors concluded that the results of the study demonstrated that Hb levels are independently associated with all ultrasonographic bone mineral parameters in unselected, community-dwelling older populations. Results also showed that osteoporosis could be best predicted in this population in individuals with Hb levels <13 g/dL (women) and <14 g/dL (men).

Laudisio A, Marzetti E, Pagano F, Bernabei R, Zuccalà G. Haemoglobin levels are associated with bone mineral density in the elderly: a population-based study. Clin Rheumatol. 2009 Feb;28(2):145-51.

NAAC Expert Commentary
The authors wish to study whether Hb levels are associated with bone density, becasue it has been recognized that anemia correlates with osteoporosis. This study by Laudisio et al is cross-sectional, in which non-selected elderly individuals in an Italian village were examined in their homes. One problem with this study is that it uses ultrasound, rather than using dual-energy x-ray absorptiometry (DEXA) for measuring bone density. The ultrasound device was used because of its portability, since elderly patients were examined in their homes. As DEXA is the standard measure, it is more difficult to evaluate the data presented by this study.

Nonetheless, the authors found that Hb levels were independently associated with bone density using a multiple regression analysis. This should heighten our awareness that anemia may be a significant contributor to osteoporosis. Further study of this intriguing possibility may help reveal whether treating anemia is effective for reducing the effects of osteoporosis and preventing fracture.

Last Updated: September 9, 2009