Applied Science and Innovative Research ISSN 2474-4972 (Print) ISSN 2474-4980 (Online) Vol. 3, No. 3, 2019 www.scholink.org/ojs/index.php/asir 153 Original Paper Osteopenia and Osteoporosis Assessed by Dual X Absorptiometry in Sickle Cell Anemia Adults Subjects Joseph Médard Kabeya Kabenkama1*, Minouche Bukumba1, Orly Kazadi2, Frederic Tshibasu1, Angele Mbongo Tanzia1, Antoine Molua Aundu1, Jean Mukaya Tshibola1, Luc Mokassa Bakumobatane1, Michel Lelo Tshikwela1 & Jean-Marie Mbuyi Muamba3 1 Department of Radiology, Kinshasa University School of Medicine and Hospital, Kinshasa, Democratic Republic of the Congo 2 Department of pediatrics, Kinshasa University School of Medicine and Hospital, Kinshasa, Democratic Republic of the Congo 3 Department of Internal Medicine, Rheumatology, Kinshasa University School of Medicine and Hospital, Kinshasa, Democratic Republic of the Congo * Joseph Médard Kabeya Kabenkama, Department of Radiology, Kinshasa University School of Medicine and Hospital, Kinshasa, Democratic Republic of the Congo Received: July 11, 2019 Accepted: July 22, 2019 Online Published: August 12, 2019 doi:10.22158/asir.v3n3p153 URL: http://dx.doi.org/10.22158/asir.v3n3p153 Abstract Background: Sickle cell anemia is the most common genetic disease in sub-Saharan Africa. It is an inherited autosomal recessive disorder characterized by chronic hemolysis secondary to falciformation of red blood cells, also responsible of ischemia, bone infarction and accompanied by serious infections and organic lesions. Normal for weight at birth, Sickle cell anemia subjects have low pre puberty growth compared to normal children and also have compromised bone remodeling balance which results in decrease of bone mass and increase of bone fragility. Several studies have established that 37% to 50% of SCA patients were osteopenic or osteoporotic. This study aims to confirm the existence of bone remodeling disorders with osteoporotic translation and to compare the values found in Congolese sickle cell adults subjects to the general population. Methods: Spine and hip DXA were conducted on 270 SS homozygotes aged 18 to 50 years (121 men and 149 women) and 359 AA homozygotes as controls (138 men and 221 women), aged from 18 to 50 years old, who agreed to participate in the study, considered as a control group. AS heterozygotes were not included in the study. www.scholink.org/ojs/index.php/asir Applied Science and Innovative Research Vol. 3, No. 3, 2019 154 Published by SCHOLINK INC. Results: AA subjects shows higher density (BMD) and Bone mineral content (BMC) values. Both SCA and AA controls showed the characteristic curve with peak bone mass at the fourth decade of life, followed by a decay with age. The difference in BMD and BMC with the control population ranged from 7.94% to 26.34% (average of 16.02%) which means -0.8 to -2.7 standard deviations, whereas, compared to the T -score in the Congolese population, was 11.6% to 22.15% less (average of -17.5%) equivalent of -0.9 to -2 standard deviations. The overall decrease in bone mass rate for -2.5 DS of the T-score was: -28.4% and 33.2% for -2 DS of T-score. Conclusion: SCA subjects shows high rate of osteopenia and osteoporosis and are more likely at risk for fractures. Keywords Bone mass, DXA, sickle cell anemia, osteopenia, osteoporosis, black, central Africa, adult 1. Introduction Sickle cell anemia (SCA), the most common genetic disease in sub-Saharan Africa, is an inherited autosomal recessive disorder (Rees et al., 2010). A mutation causes the replacement of hydrophilic glutamic acid by valine, which is hydrophobic, thereby explaining the fragility of the red blood cell in sickle cell patients under hypoxic conditions. Acute attacks (hematologic and vaso-occlusive) as well as chronic complications of this disease are the result of falciformation of red blood cells and chronic hemolysis, which are also responsible for ischemia, bone infarction and hyperplasia of the red marrow with a reduction in the trabecular component. SCA is furthermore accompanied by serious infections and organic lesions (Rees et al., 2010; Bookchin et al., 1996; Kazadi et al., 2017). SCA patients have normal weights at birth but low pre-pubertal growth compared to normal children. Chronic anemia results in abnormalities in skeletal maturation (Kazadi et al., 2017; Piel et al., 2013; Henderson et al., 1994; Luban et al., 1982; Barden et al., 2000). This feature is associated with osteomyelitis and repeated bone infarction, with a reduction in the rate of bone formation as a consequence of compromised bone remodeling balance (Henderson et al., 1994; Luban et al., 1982; Barden et al., 2000; Bennet et al., 1990; Meeuwes et al., 2013). Great progress has been made in the management of this hemoglobinopathy, which permits the elderly patients with SCA to survive in developed countries. However, the lack or absence of financial and sometimes human resources skills reduces access to quality care in low-income countries such as the DRC (Kazadi et al., 2017; Aloni et al., 2014; Williams et al., 2016; Chaturvedi et al., 2016; Matthie et al., 2015; Vanderjagt et al., 2002; Arlet et al., 2013; Emodi et al., 2001; Finkelstien et al., 1996). In several studies, approximately half of the 35-year-old SCA patients have apophyseal necrosis, while others report stress fractures, vertebral collapse, sclerosis of the joint surfaces, and even orbital www.scholink.org/ojs/index.php/asir Applied Science and Innovative Research Vol. 3, No. 3, 2019 155 Published by SCHOLINK INC. compressions or problems that result from the decrease in bone mass and the increase in bone fragility and fracture risk (Arlet et al., 2013; Emodi et al., 2001; Finkelstien et al., 1996; Demirbas et al., 2004; Ganesh et al., 2001; Bahebeck et al., 2002). Several studies have reported that 37 to 50% of SCA patients were osteopenic or osteoporotic which is associated with the foci of osteomyelitis and bone infarction and leads to an increased risk of fracture in SCA patients (Arlet et al., 2013; Bahebeck et al., 2002; Bennet et al., 1990; Meeuwes et al., 2013; Emodi et al., 2001; Demirbas et al., 2004; Finkelstien et al., 1996; Ganesh et al., 2001; Lal et al., 2006). The majority of these studies were conducted out of sub-Saharan Africa, and, despite a relatively different biological, genotypic and phenotypic profile, the Congolese SCA clinical profile reflects an equivalent impact of this hemoglobinopathy on the bone system, suggesting the presence of remodeling abnormalities in the setting of low bone mass (Kabeya et al., 2017; Kazadi et al., 2017; Mikobi et al., 2017; Mikobi et al., 2017; Tshilolo et al., 2012; Platt et al., 1984). The aim of this study was to compare the values found in Congolese SCA subjects to those of a control group matched for age and sex and establish the existence of bone remodeling disorders with osteoporotic translation using DXA. 2. Material and Methods 2.1 Subjects 1862 respondents of a public media call for low cost checkup including DXA were examined by a physician and underwent clinical, biological and imaging investigations planned for the checkup. This cross-sectional study included a total of 629 AA homozygotes (138 men and 221 women), aged from 18 to 50 years old, who agreed to participate in the study, considered as a control group and 270 SS homozygotes aged 18 to 50 years (121 men and 149 women) as subjects of the study. AS heterozygotes were not included in the study. Inclusion criteria: -black Congolese bantu for origin. -No vertebral fractures or other high or low energy fractures in the antecedents. -be free of any disease or drug treatment known to affect bone metabolism for a period greater or equal to 3 months. Inhalation steroids, smoking, physical inactivity and athleticism, although likely to influence bone metabolism, were not exclusion criteria. 2.2 Measurements 2.2.1 Anthropometric parameters (age, height and weight) were collected according to standardized procedures. 2.2.2 BMI was calculated by dividing weight in kilograms by height in square meters [BMI in kg / m² = w (kg) / T² (m)]. Patients BMI was quoted in 6 steps according to the system proposed by WHO (WHO, 2006). www.scholink.org/ojs/index.php/asir Applied Science and Innovative Research Vol. 3, No. 3, 2019 156 Published by SCHOLINK INC. 2.2.3 DXA examinations were performed using a hologic densitometer: Densitometer Hologic QDR Discovery (Hologic, Inc., Bedford, Mass., USA) The BMC and BMD of the patients was measured at the hip (total hip), at the lumbar spine (anteroposterior projection of L1 to L4), distal 1/3 of the forearm and carp. 2.3 Statistical Analysis Statistical analyses were performed using commercially available software (SPSS version 21). The student t test was performed to compare the means (averages). The search for associated factors was done using linear regression. The threshold for significance was set at 0.05. 2.4 Others Statements The design of the study was approved by the local ethics Committee and the study was conducted in accordance with the Helsinki Declaration for Human Studies. The authors declare that they have no conflicts of interest. 3. Results 3.1 Characteristics of the Subjects Parameters measured in SCA subjects and in the control, group are shown in Table 1. Table 1. General Characteristics of Subjects According to Type of Hemoglobin Variables all n=629 AA n=359 SS n=270 p Age (years) 37,4±13,7 44,2±12,9 35,1±7,0 <0,001 BMI 27,6±5,8 28,6±5,8 26,1±6,6 0,033 Hydroxy vitamine D 32,3±9,4 31,0±9,3 37,1±8,2 <0,001 Calcium 9,7±0,7 9,6±0,6 10,0±0,6 <0,001 ALT/SGPT 21,0±4,2 21,1±7,2 20,3±2,1 0,807 fasting glucose 91,4±5,6 94,4±27,7 79,8±6,3 <0,001 iron 72,9±9,7 77,4±31,0 55,7±9,7 <0,001 TSH 3rd generation 2,5±0,7 2,8±0,6 1,5±0,1 0,195 Cholesterol 204,6±36,2 202,5±39,3 212,9±18,1 0,032 DXA L1-L4: BMC (g) 14,9±3,5 15,1±3,5 13,9±3,2 <0,010 DXA L1-L4: BMD (g/cm2) 1,04±0,2 1,05±0,2 0,90±0,27 <0,001 DXA hip total BMC(g) 38,8±9,3 45,0±8,9 38,1±9,1 <0,001 DXA hip total BMD (g/cm2) 12,1±9,7 21,1±2,5 15,5±5,2 <0,001 DXA carp: BMC(g) 3,4±0,7 3,6±0,7 2,8±0,5 <0,001 DXA carp: BMD (g/cm2) 0,66±0,22 0,98±0,09 0,88±0,27 0,098 DXA forearm 1/3: BMC(g) 3,1±1,8 3,4±1,9 1,8±0,09 <0,001 DXA forearm 1/3: BMD (g/cm2) 0,77±0,07 0,78±0,08 0,70±0,02 0,560 www.scholink.org/ojs/index.php/asir Applied Science and Innovative Research Vol. 3, No. 3, 2019 157 Published by SCHOLINK INC. Comparison of the two groups showed a lower BMI among SCAs, although of moderate statistical significance (p = 0.033). Blood levels of vitamin D, serum calcium and cholesterol were significantly higher in SCA than in the control, (p = 0.032 to p < 0.001) whereas serum iron was significantly lower in SCA (p < 0.001)). Excluding carpal BMD and distal 1/3 of the forearm, which showed non-significant differences (p = 0.098 and p = 0.56), the others bone mass parameters (BMC and BMD) at total hip and lumbar vertebrae were significantly higher in AA homozygotes than in SCA (p < 0.001). 3.2 Age Related Evolution of Biometrical and Biological Parameters Table 2 shows age- and sex -related evolution of the parameters measured in SCA subjects. Table 2. Age- and Sex -related Evolution of Biometrical and Biological Parameters MEN WOMEN Age (years) 18-30 31-40 41-50 18-30 31-40 41-50 Weight (Kg) 63,5±6,3 65,7±9,4 55,00 59,94±7,44 60,52±6,39 67,00±8,50 Height (m) 1,68±0,07 1,73±0,01 1,74 1,64±0,10 1,66±0,07 1,63±0,14 BMI (kg/m2) 22,08±1,90 25,57±2,32 17,5 22,47±3,96 26,13±2,23 27,99±6,15 OH vit. D 39,00±10,49 42,71±0,95 42,00 35,21±7,13 35,36±9,05 39,36±8,12 Calcium 10,23±0,64 10,39±0,36 9,70 9,90±0,63 9,83±0,66 10,14±0,56 ALT/SGPT 20,50±1,27 20,36±1,60 19,00 20,56±1,14 19,55±3,17 21,50±2,57 Fast glucose 81,45±3,92 84,57±3,41 86,00 77,69±5,83 79,00±7,11 82,00±7,75 Pp glucose 89,15±2,98 90,29±3,40 89,00 88,50±4,33 88,32±4,19 82,14±21,18 Serum iron 50,15±8,97 49,43±4,83 54,00 58,50±7,27 57,47±13,21 55,07±6,87 TSH 3rd gen 1,40±0,05 1,42±0,06 1,32 1,47±0,12 1,48±0,14 1,53±0,10 Cholesterol 199,5±8,8 208,4±10,7 192,00 218,3±15,2 213,4±23,08 217,7±20,4 Men had a larger size at all ages. Height has increased among men with the aging while it remained almost stationary in the female sex. The BMI is stackable in both sexes except in the 40-49 years age group where men disclosed a lean type BMI while women in this category were overweight. The other parameters do not show any significant gender or age differences. 3.3 BMD and BMC Comparative Data According to the Type of Hemoglobin versus T-score Table 3 shows the differences in BMD and BMC between SCA, AA and T-score according to the type of hemoglobin. www.scholink.org/ojs/index.php/asir Applied Science and Innovative Research Vol. 3, No. 3, 2019 158 Published by SCHOLINK INC. Table 3. Differences/Gap in BMC and BMD in Percent According to Hemoglobin Type Parameter SCA AA Gap SCA Versus AA (%) T-score Gap SCA Versus T-score (%) VERTEBRAL BMC (g) 13,6±3,2 15,1±3,5 7,9 15.98±2.81 16,26 VERTEBRAL BMD (g/cm2) 0,90±0,27 1,05±0,2 14,28 1.14 ±0.14 22,15 HIP BMC (g) 3,81±0,91 4,50±0,89 15,34 4.31 ±0.80 11,6 HIP BMD(g/cm2) 1,55±0,52 2,11±0,25 26,54 1.94 ±0.17 20,11 The difference in BMC and BMD between SCA and controls group ranged from 7.94 to 26.34% (average of 16.02%) with a standard deviation ranging from -0.8 to -2.7. By contrast, compared to the T-score (Kabeya et al., 2017), the values were 11.6 to 22.15% less and average of -17.5%, with a SD ranging from -0.9 to -2. The overall decrease in the bone mass rate for -2.5 DS of the T-score was -28.4%, and it was 33.2% for -2 DS of the T-score. Table 4 and Figure 1 show Age- and sex-related variation in BMD according to type of hemoglobin. Table 4. Age-and Sex-related Variation in SPINE BMD According to Type of Hemoglobin Age Group (years) < 31 31-40 41-50 BMD mean AA men (g/cm2) 1,31 1,4121 1,1231 BMD mean AA women (g/cm2) 1,07 1,11192 1,0831 BMD mean SS men (g/cm2) 0,97 1.0412 0,9732 BMD mean SS women (g/cm2) 0,85 0,926 0,752 Figure 1. Age-and Sex-related Variation in SPINE BMD According to Type of Hemoglobin 1.07 1.11 1.08 1.31 1.41 1.23 0.85 0.92 0.75 0.97 1.04 0.97 0 0.2 0.4 0.6 0.8 1 1.2 1.4 1.6 <30 30 - 40 41 - 50 Women AA Men AA Women SS Men SS www.scholink.org/ojs/index.php/asir Applied Science and Innovative Research Vol. 3, No. 3, 2019 159 Published by SCHOLINK INC. Bone mineral density is higher in AA homozygotes at all ages. Females had lower rates than males of the same age. Bone mineral density showed a peak of bone mass at the fourth decade of life in both SCA and AA controls followed by a decay with age. 3.4 Relationship between Parameters The linear regression relationships between densitometric, biometric and biological parameters did not reveal significant relationships in SCA subjects. Age showed a link, while vitamin D levels (Figures 2 and 3) showed no significant effects. Figure 2. Regression of Lumbar Spine BMD by Vitamin D in SCA Figure 3. Regression of the BMC of the Lumbar Spine by Vitamin D in SCA r =0,161 p= 0,405 0 0.2 0.4 0.6 0.8 1 1.2 1.4 1.6 1.8 2 0 10 20 30 40 50 60 70 D X A B M D C O LO N N E HYDROXY VIT D . r = 0,094 p = 0,085 0 5 10 15 20 25 30 0 10 20 30 40 50 60 70 80 D X A B M C C O LO N N E HYDROXY VIT D . www.scholink.org/ojs/index.php/asir Applied Science and Innovative Research Vol. 3, No. 3, 2019 160 Published by SCHOLINK INC. These figures expressed the absence of significant link between the parameters of the bone mass (BMC and BMD) at the spine with vitamin D levels. 4. Discussion The aim of this study was to establish and confirm in Congolese SCA subjects, using DXA, the existence of bone remodeling disorders with osteoporotic translation and to compare the BMC and BMD values found in SCA Congolese subjects to those of a control population matched for age and sex. Comparison of the two groups showed a miscellaneous difference between SCA subjects and controls (Table 1). The BMI in SCA patients (Table 1) was lower than that of AA controls, although the data was of relatively moderate statistical significance (p = 0.033). This finding seems to be a phenomenon related to nutritional status, repeated infectious episodes and the metabolic status in SCA patients. A low BMI in SCA is richly documented in children and adults with SCA who have pre- and post-pubertal growth deficits and a weight at the 5th to 10th percentile of normal weight for age in some studies (Kazadi et al., 2017; Henderson et al., 1994; Aloni et al., 2014; Finkelstien et al., 1996). Kazadi et al. (2017) and Platt et al. (1984) reported stunting, impaired body composition, delayed skeletal and sexual maturation, and chronic nutritional deficiencies in children with SCA resulting in errors when WHO or American population growth curves are used (Chawla et al., 2013; Kazadi et al., 2017; Muchanga et al., 2014; Reed et al., 1987; WHO, 2006). In our study group (Table 1), the majority of subjects over 30 years old were nonetheless overweight. Mikobi et al. (2017) links a near-overweight BMI to a common phenotypic type in the SCA population in Congo with a high average steady-state hemoglobin concentration and significantly higher rate of fetal hemoglobin (HbF). Overweight subjects was also found in a hight proportion in the Congolese population studied by DXA (Kabeya et al., 2017) and in the Congolese peri-menopausal by Muchanga et al. (2014). Being overweight appeared to be a stigma in this population undergoing an epidemiologic transition in weights. In this study (Table 2), unexplained higher blood levels of vitamin D (p > 0.001), serum calcium p > 0.001), and cholesterol (p = 0.032) were seen in SCA patients versus the controls. Previous studies have reported that patients with SCA have more vitamin D deficiency than their counterparts who are supposedly in good health (Samim et al., 2013; Chapelon et al., 2009; Ross et al., 2011). The role of the sun on the rate of vitamin D production cannot explain such a difference according to the type of hemoglobin (Buison et al., 2005). Vitamin D is an important factor in bone formation. Nevertheless, previous studies on BMD in SCA patients including measurement of 25-hydroxyvitamin D levels, revealed a decrease in vitamin D in www.scholink.org/ojs/index.php/asir Applied Science and Innovative Research Vol. 3, No. 3, 2019 161 Published by SCHOLINK INC. almost all participants, but no significant association between vitamin D and BMD was noted in our subjects (Figures 3 and 4) as in the studies by Buison et al. (2005) as well as that of Samim-Özen et al. (2013). It is known that vitamin D deficiency is a common, serious medical condition that significantly affects the health and well-being of older adults even in tropical countries and sunny climates. In addition, low vitamin D is linked osteoporosis (MacLaughlin et al., 1985). In Europe, representative residents from the SENECA study of older Europeans aged 75-76 years old showed 36% of men and 47% of women were vitamin D deficient, most markedly in southern Europe, in a survey of 19 towns in 11 countries in the winter of 1988-1989 (Van der Wielen et al., 1995), Furthermore, in the study of Bullamore et al. (1970), Calcium absorption was measured by plasma radioactivity after oral and malabsorption of calcium in the elderly were linked to vitamin-D deficiency, and plays a significant role in the pathogenesis of fractures in old people. We don’t have subjects nor control aged 50 and over. BMC and BMD (Table 3) at the total hip and lumbar vertebrae were generally significantly higher in AA homozygotes than in SCA patients and varied with age and sex (Table 4). Figure 3 showed curves of the same profile but under offset. The overall BMD rate below 2.5 SD was: 28.4% and it was 33.2% for -2 SD of T-score in this study. The prevalence of low lumbar spine BMD (Z-score < -2 SD) varies from country to country. Low lumbar spine BMD was 41% among Brazilian SCAs [9], 56% in the United States (Van der Wielen et al., 1995; Miller et al., 2006) and 19% in France (Ross et al., 2011). The differences in the observed low BMD percentages can be explained by the difference in selection criteria, quality of care, difference in nutritional status, and size of samples among the various ethnicities. In USA (Miller et al., 2006; Lal et al., 2006) the patients recruited were heavily ill. In Brazil, the sample size was relatively small (Meeuwes et al., 2013) whereas our sample is made of ambulatory patients without, serious clinically problems. With T-scores ranging from -0.9 to -2 standard deviations and Z-scores ranging from -0.8 to -2.7 standard deviations, the present study showed overall bone mass deficits superimposed on the Brazilian data which ranged from -0.8 to -1.81 for the T-score and an average of -2 SD for the Z-score, which appeared to be more deficient as the BMI was low (Meeuwes et al., 2013). In the absence of normative size data for age (Kazadi et al., 2017) in our population, we could not verify the assertion regarding the significant relationships observed between BMD and low height for age, weight for age and BMI for age reported in several SCA studies (Henderson et al., 1994; Luban et al., 1982; Barden et al., 2000; Meeuwes et al., 2013; Bullamore et al., 1970; Lal et al., 2006; Miller et al., 2006; Baldanzi et al., 2011) but also between BMI and BMD in the general population (Kabeya et al., 2017). Other studies have found no relationship between height or BMI and BMD (Chapelon et al., 2009; Lal A et al., 2006; Sarrai et al., 2006). www.scholink.org/ojs/index.php/asir Applied Science and Innovative Research Vol. 3, No. 3, 2019 162 Published by SCHOLINK INC. The present study did not seek to evaluate the quantity and the quality of the food intake of our subjects who are considered weak (Kazadi et al., 2017), Therefore, we can not determine the contributions of calories, calcium, microelements or vitamin D in the disclose of low BMD. However, given that patients with SCA have high nutritional needs since they have a chronic hyper-metabolic state (Bookchin et al., 1996; Kazadi et al., 2017; Piel et al., 2013; Henderson et al., 1994; WHO, 2006; Chawla et al., 2013; Reed et al., 1987; Muchanga et al., 2014; Samim et al., 2013; Chapelon et al., 2009; Ross et al., 2011; Buison et al., 2005), low BMD is expected to result partly from inadequate nutritional intake. The exact mechanism leading to low BMD in SCA patients is probably multifaceted. Chronic kidney diseases related to sickle cell anemia may also serve as a factor. SCA patients are known to have progressive decline in kidney function associated with microalbuminuria (Aloni et al., 2017), and in adulthood, a decline in kidney function appears to be progressive from 40 years of age Complications associated with SCA including bone infarction, osteonecrosis and osteomyelitis have a direct effect on bone structures. Infarcted areas of the bone are sites at high risk for osteomyelitis. In addition, repeated episodes of decreased blood flow and bone marrow hyperplasia can lead to loss of bone trabeculae, altering bone strength and increasing fracture risk. This finding is due to the total bone strength being based on the combination of material properties (the mineral phase and the composition of the extracellular matrix), bone volume, and the micro and macro architecture. 5. Conclusion Sickle Cell Anemia patients have low bone mass, osteopenia and osteoporosis, and greater susceptibility to fractures References Aloni, M. N. et al. (2017). Prevalence and determinants of microalbiminuria in children suffering from sickle cell anemia in steady state. Clinical Kidney Journal, 10(4), 479-486. https://doi.org/10.1093/ckj/sfx058 Aloni, M. N., & Nkee, L. (2014). Challenge of managing sickle cell disease in a pediatric population living in kinshasa, democratic republic of Congo: A sickle cell center experience Hemoglobin (Vol. 38, No. 3, pp. 196-200). Arlet, J. B. et al. (2013). Relationship between vitamin D deficiency and bone fragility in sickle cell disease: A cohort study of 56 adults. Bone, 52, 206-211. https://doi.org/10.1016/j.bone.2012.10.005 Bahebeck, J., Ngowe, N. M., Monny, L. M., Sosso, M., & Hoffmeyer, P. (2002). Stress fracture of the femur: A rare complication of sickle cell disease. Revue de Chirurgie Orthopedique et Reparatrice de L’Appareil Moteur, 88, 816-818. www.scholink.org/ojs/index.php/asir Applied Science and Innovative Research Vol. 3, No. 3, 2019 163 Published by SCHOLINK INC. Baldanzi, G. et al. (2011). Low bone mass density is associated with hemolysis in Brazilian patients with sickle cell disease. Clinics (Sao Paulo), 66, 801-805. https://doi.org/10.1590/S1807-59322011000500015 Barden, E. M. et al. (2000). Total and resting energy expenditure in children with sickle cell disease. J Pediatr, 136, 73-79. https://doi.org/10.1016/S0022-3476(00)90053-2 Bennet, O. M., & Namnyak, S. S. (1990). Bone and Joint manisestations of sickle cell anemia. J Bone Jt Surg, 72B, 494-4998. https://doi.org/10.1302/0301-620X.72B3.2341455 Bookchin, R. M., & Lew, V. L. (1996). Pathophysiology of sickle cell anemia. Hematology/Oncology Clinics of North America, 10, 1241-1253. https://doi.org/10.1016/S0889-8588(05)70397-X Buison, A. M. et al. (2005). Bone area and bone mineral content deficits in children with sickle cell disease. Pediatrics, 116, 943-949. https://doi.org/10.1542/peds.2004-2582 Bullamore, J. R., Wilkinson, R., Gallagher, J. C., Nordin, B. E., & Marshall, D. H. (1970). Effect of age on calcium absorption. Lancet, 12(2), 535-537. https://doi.org/10.1016/S0140-6736(70)91344-9 Chapelon, E. et al. (2009) Osteopenia and vitamin D deficiency in children with sickle cell disease. European Journal of Haematology, 83, 572-578. https://doi.org/10.1111/j.1600-0609.2009.01333.x Chaturvedi, S., & Debaun, M. R. (2016). Evolution of sickle cell disease from a life-threatening disease of children to a chronic disease of adults: The last 40 years. American Journal of Hematology, 91(1), 5-14. https://doi.org/10.1002/ajh.24235 Chawla, A. et al. (2013). Weight status of children with sickle cell disease. Pediatrics, 131(4), e1168-e1173. https://doi.org/10.1542/peds.2012-2225 Demirbas, K. A., Aktener, B. O., & Unsal, C. (2004). Pulpal necrosis with sickle cell anaemia. International Endodontic Journal, 37, 602-606. https://doi.org/10.1111/j.1365-2591.2004.00853.x Emodi, J. I., & Okoye, I. J. (2001). Vertebral bone collapse in sickle cell disease: A report of two cases. East African Medical Journal, 78, 445-446. https://doi.org/10.4314/eamj.v78i8.9000 Finkelstien, J. S., Klibanski, A., & Neer, R. M. (1996) A longitudinal evaluation of bone mineral density in adult men with histories of delayed puberty. The Journal of Clinical Endocrinology & Metabolism, 81, 1152-1155. https://doi.org/10.1210/jc.81.3.1152 Ganesh, A. et al. (2001). Orbital involvement in sickle cell disease: A report of five cases and review literature. Eye, 15, 774-780. https://doi.org/10.1038/eye.2001.248 Henderson, R. A., Saavedra, J. M., & Dover, G. J. (1994). Prevalence of Impaired Growth in children with homozygous sickle cell anemia. Am J Med Sci., 307, 405-407. https://doi.org/10.1097/00000441-199406000-00004 Kabeya Kabenkama, J. M., Tozin, R. R., Jean Jacques Malemba, & Jean-Marie Mbuyi Muamba. (2017). Normative Values of Bone Mineral Content and Bone Mineral Density Assessed by Double X-ray Absorptiometry in Congolese Urban Women. Applied Science and Innovative Research, 1(2), 142-155. https://doi.org/10.22158/asir.v1n2p141 www.scholink.org/ojs/index.php/asir Applied Science and Innovative Research Vol. 3, No. 3, 2019 164 Published by SCHOLINK INC. Kazadi, AL. et al. (2017). Factors Associated with Growth Retardation in Children Suffering from Sickle Cell Anemia: First Report from Central Africa. Hindawi Anemia Volume. https://doi.org/10.1155/2017/7916348 Lal, A., Fung, E. B., Pakbaz, Z., Hackney-Stephens, E., & Vichinsky, E. P. (2006). Bone mineral density in children with sickle cell anemia. Pediatric Blood & Cancer, 47, 901-906. https://doi.org/10.1002/pbc.20681 Luban, B. J., Leiken, S. L., & August, G. A. (1982). Growth and development in sickle cell anemia. Am J Pediatr Hematol Oncol., 4, 61-65. Mac Laughlin, J., & Holick, M. F. (1985). Ageing decreases the capacity of human skin to produce vitamin D3. J Clin Invest., 76, 1536-1538. https://doi.org/10.1172/JCI112134 Matthie, N., & Jenerette, C. (2015). Sickle cell disease in adults: Developing an appropriate care plan. Clinical Journal of Oncology Nursing, 19(5), 562-568. https://doi.org/10.1188/15.CJON.562-567 Meeuwes, M. et al. (2013). Bone mineral density, growth, pubertal development and other parameters in Brazilian children and young adults with sickle cell anaemia. Tropical Medicine and International Health, 18(12), 1539-1546. https://doi.org/10.1111/tmi.12211 Mikobi, T. M. et al. (2017). Association between sickle cell anemia and alpha thalassemia reveals a high prevalence of the α3.7 triplication in Congolese patients than in worldwide series. J Clin Lab Anal. https://doi.org/10.1002/jcla.22186 Mikobi, T. M. et al. (2017). Clinical phenotypes and the biological parameters of Congolese patients suffering from sickle cell anemia: A first report from Central Africa. J Clin Lab Anal., 31(6). https://doi.org/10.1002/jcla.22140 Miller, R. G. et al. (2006). High prevalence and correlates of low bone mineral density in young adults with sickle cell disease. American Journal of Hematology, 81, 236-241. https://doi.org/10.1002/ajh.20541 Muchanga Sifa, M. J. et al. (2014). Prevalence and predictors of metabolic syndrome among Congolese pre- and postmenopausal women. Climacteric, 17(4), 442-448. https://doi.org/10.3109/13697137.2013.856403 Piel, F. B. et al. (2013). Global burden of sickle cell anaemia in children under five, 2010-2050: Modelling based on demographics, excess mortality, and interventions. PLoS Medicine, 10(7). https://doi.org/10.1371/journal.pmed.1001484 Platt, O. S., Rosenstock, W., & Espeland, M. A. (1984). Influence of sickle hemoglobinopathies on growth and development. The New England Journal of Medicine, 311, 7-12. https://doi.org/10.1056/NEJM198407053110102 Reed, J. D., Redding-Lallinger, R., & Orringer, E. P. (1987). Nutrition and sickle cell disease. American Journal of Hematology, 24, 441-455. https://doi.org/10.1002/ajh.2830240416 Rees, D. C., Williams, T. N., & Gladwin, M. T. (2010). Sickle-cell disease. The Lancet, 376(9757), 2018-2031. http://www.ncbi.nlm.nih.gov/pubmed/?term=Mikobi%20TM%5BAuthor%5D&cauthor=true&cauthor_uid=28276593 http://www.ncbi.nlm.nih.gov/pubmed/?term=Mikobi%20TM%5BAuthor%5D&cauthor=true&cauthor_uid=28116772 www.scholink.org/ojs/index.php/asir Applied Science and Innovative Research Vol. 3, No. 3, 2019 165 Published by SCHOLINK INC. Ross, A. C., Taylor, C. L., Yaktine, A. L., & Del Valle, H. B. (2011). Dietary Reference Intakes for Vitamin D and Calcium. National Academies Press, Washington, DC (US). Samim, Özen. et al. (2013). Frequency and Risk Factors of Endocrine Complications in Turkish Children and Adolescents with Sickle Cell Anemia. Turk J Haematol., 30(1), 25-31. https://doi.org/10.4274/tjh.2012.0001 Sarrai, M. et al. (2006). Bone mass density in adults with sickle cell disease. British Journal of Haematology, 136, 666-672. https://doi.org/10.1111/j.1365-2141.2006.06487.x Tshilolo, L. et al. (2012). Foetal haemoglobin, erythrocytes containing foetal haemoglobin, and hematological features in Congolese patients with sickle cell anaemia. Anemia. https://doi.org/10.1155/2012/105349 Van der Wielen, R. P., Lowik, M. R., van den Berg, H., de Groot, L. C., Haller, J., Moreiras, O., & van Staveren, W. A. (1995). Serum vitamin D concentrations among elderly people in Europe. Lancet, 346, 207-210. Vanderjagt, D. J., Bonnet, C., Okolo, S. N., & Glew, R. H. (2002). Assessment of Bone Status of Nigerian Children with Sickle Cell Disease Using Calcaneal Ultrasound and Serum Markers of Bone Metabolism. Calcif Tissue Int., 71, 133-140. https://doi.org/10.1007/s00223-001-1107-x WHO Multicenter Growth Reference Study Group. (2006). WHO Child Growth Standards: Length/Height-for-Age, Weight-for-Age, Weight-for-Length, Weight-for-Height and Body Mass Index-for-Age: Methods and Development, World Health Organization, Geneva, Switzerland. Williams, T. N. (2016). Sickle cell disease in Sub-Saharan Africa. Hematology/Oncology Clinics of North America, 30(2), 343-358. https://doi.org/10.1016/j.hoc.2015.11.005